Kyushu University Academic Staff Educational and Research Activities Database
List of Papers
Jun Tanimoto Last modified date:2019.12.09

Professor / Department of Advanced Environmental Science and Engineering / Faculty of Engineering Sciences


Papers
1. Jun Tanimoto, Kyaw Thu, Hiroshi Furuno, Nasruddin, Mohd Fairus Mohd Yasin, Muhammad Arif Budiyanto, Editorial, Evergreen, 10.1007/s11282-007-0065-z, 6, 2, iii-iv, 2019.06.
2. K. M.Ariful Kabir, Jun Tanimoto, Dynamical behaviors for vaccination can suppress infectious disease – A game theoretical approach, Chaos, solitons and fractals, 10.1016/j.chaos.2019.04.010, 123, 229-239, 2019.06, To avoid the infection, the epidemic outburst plays a significant role that encourages people to take vaccination and induce behavioral changes. The interplay between disease incidence, vaccine uptake and the behavior of individuals are taking place on the local time scale. Here, we analyze the individual's behavior in disease-vaccination interaction model based on the evolutionary game approach that captures the idea of vaccination decisions on disease prevalence that also include social learning. The effect of herd immunity is partly important when the individuals are deciding whether to take the vaccine or not. The possibility that an individual taking a vaccination or becoming infected depends upon how many other people are vaccinated. To apprehend this interplay, four strategy updating rules: individual based risk assessment (IB-RA), society based risk assessment (SB-RA), direct commitment (DC) and modified replicator dynamics (MRD) are contemplated for game theoretical approach by how one individual can learn from society or neighbors. The theory and findings of this paper provide a new perspective for vaccination taking policy in daily basis that provision of prompt learning with the collective information reliefs to reduce infection, which gives a new ‘vaccination game’ from other previous models..
3. K. M.Ariful Kabir, Jun Tanimoto, Analysis of epidemic outbreaks in two-layer networks with different structures for information spreading and disease diffusion, Communications in Nonlinear Science and Numerical Simulation, 10.1016/j.cnsns.2019.01.020, 72, 565-574, 2019.06, A two-layer susceptible-infected-recovered/unaware-aware (SIR-UA) epidemic model is presented to analyze the effect of different heterogeneous networks in a population. Random, scale-free, and small-world network topologies are tested to investigate the impact of awareness on the spread of epidemics in a two-layer network with diverse combinations of degree and structure. Susceptible and infected (both unaware and aware) individuals are associated with their neighboring nodes in a social network structure with various degree distributions. In the two-layer SIR-UA epidemic model, a virtual network represents the connections that spread information, while a physical network represents the physical social interactions that spread diseases. We test various combinations of network structures in virtual or physical networks, to understand the impact of information diffusion on the spread of epidemics in a heterogeneous network structure. Then, the effects of awareness on the spread of a disease are discussed. Finally, phase diagrams are illustrated to reveal the final regions covered by an epidemic with various network parameters. We find that a disease spreads less if the virtual social network is more connected than the network of physical connections..
4. Tetsushi Ono, Aya Hagishima, Jun Tanimoto, Sheikh Ahmad Zaki, Naja Aqilah Hisham, Statistical analysis of air conditioning peak loads of multiple dwellings, 13th REHVA World Congress, CLIMA 2019 E3S Web of Conferences, 10.1051/e3sconf/201911104057, 111, 2019.08, Evaluation of the aggregated air-conditioning load of multiple dwellings is important for demand response through the optimum control of numerous air-conditioners (A/Cs), for development of smart-city or smart-community technologies. However, past studies have mainly focused on the characteristics of A/C load in a single household. With this background, the authors conducted statistical analysis of time-series data for A/C electricity consumption in 489 dwellings in Osaka, Japan, and 20 dwellings in Kuala Lumpur, Malaysia to grasp the feature of aggregated A/C load of multiple dwellings. The findings of this analysis are followings: 1) the aggregated A/C load peak per dwelling decreased by almost 50% as the number of dwellings increased from 1 to 10, due to the offset of the diverse time-patterns of A/C load. 2) The occurrence of the top 2.5% A/C load shows strong time and date dependency for an A/C load aggregated by many dwellings..
5. C. Hirose, Naoki Ikegaya, Aya Hagishima, Jun Tanimoto, Outdoor measurement of wall pressure on cubical scale model affected by atmospheric turbulent flow, Building and Environment, 10.1016/j.buildenv.2019.106170, 160, 2019.08, Most studies on indoor ventilation have utilized wind-tunnel experiments (WTEs) or computational fluid dynamics based approaches under well-controlled flow conditions. However, the effects of urban boundary layer flow with variable wind directions and various turbulence scales on the ventilation driven by the pressure differences between the upwind and downwind sides of a building within a block array is still under discussion. Therefore, we conducted outdoor experiments at comprehensive outdoor scale model (COSMO) experiment sites in an urban climate to clarify the relationships between the building wall pressure differences and the approaching flow. The pressure coefficients for the outdoor site were comparable with those obtained during previous WTEs. Accordingly, temporal variations in the wind speed and pressure coefficient on the target block were investigated in detail using low-pass filtering operations. The relationships between the filtered wind speed and the pressure differences indicate that the slower temporal variations in the wall pressure showed good agreement with the filtered approaching flow. In addition, the correlation coefficient between the filtered wind speed and the wall pressure differences quantified the apparent coherence between the turbulent flow and the ventilation rate. Furthermore, the statistics of the ventilation rate were determined based on the conventional model to clarify the effects of the turbulent flow on the natural ventilation rate. The ratios between the mean and short-term ventilation rates imply that the short-term ventilation rate presented dramatic temporal fluctuations owing to the various scale turbulence generated by the atmospheric flow..
6. Muntasir Alam, Masaki Tanaka, Jun Tanimoto, A game theoretic approach to discuss the positive secondary effect of vaccination scheme in an infinite and well-mixed population, Chaos, solitons and fractals, 10.1016/j.chaos.2019.05.031, 125, 201-213, 2019.08, Pre-emptive vaccination policy used in controlling the rapid spreading of infectious diseases is considered as one of the most challenging issues imposed to mankind, causing enormous death tolls over the years. This paper dedicatedly studies the dilemma effect coming from the failure of getting perfect immunity to those individuals who committed vaccination earlier. Therefore, we propose a new theoretical model that slows down the infection spreading and also facilitates quicker recovery time than what the previous model does even if a vaccinator fails to obtain perfect immunity. We name this effect as the “positive secondary effect” of vaccination as it gives a second chance to the vaccinators which in return subdues the rapid spreading that helps in producing better social average payoff as well as keeping the final epidemic size smaller. Moreover, to address the positive secondary effect more precisely, we introduce two different parameters; namely, relaxation parameter (η) and foster parameter (δ) in two different directions to quantify the individual effects resulting from each of the parameter space as well as their superposition effect. An in-depth discussion focuses on the influential role played by our proposed model via discounting and faster recovery effects while a second chance is given to the vaccinators. In addition, we also examine the situation when discounting effect brought by η outperforms very much than its faster recovery controlled by δ as well as the superposition effects. Unlike all previous studies dealing with vaccination game, we pay much attention to investigating the secondary effect of imperfect vaccination policy. Our proposed theoretical scheme completely reproduces the decision-making process of choosing an imperfect provision based on evolutionary game theory entailed with the widely used SIR (Susceptible–Infected–Recovered) epidemic model. Without considering any spatial structure and perfect vaccination policy, our model presumes the population being infinite and well-mixed to represent the infection spreading dynamics mathematically. This study is conducted throughout using the so-called theoretical approach. Besides that, three different updating rules based on evolutionary game theory have also been considered to investigate all possible situations. Later on, we draw 2D full phase diagrams showing the final epidemic size, vaccination coverage, and average social payoff quantitatively. Finally, our theoretical result is compared with the counterpart result obtained from the multi-agent simulation (MAS) approach and a good agreement is found, hence the appropriateness of the proposed model is fully justified..
7. K. M.Ariful Kabir, Jun Tanimoto, Vaccination strategies in a two-layer SIR/V–UA epidemic model with costly information and buzz effect, Communications in Nonlinear Science and Numerical Simulation, 10.1016/j.cnsns.2019.04.007, 76, 92-108, 2019.09, The promptness with which individuals respond to information has an important effect on the spread of epidemics. To study this effect, we establish a two-layer SIR/V epidemic model that incorporates the effects of information buzz and information costs in the framework of a vaccination game. Previous studies on this issue have generally assumed that only unaware people can become aware, and the relative vaccination cost is used to update their strategies for avoiding infection. Firstly, we introduce the idea that aware people can also become unaware because of a wicked rumor about a beneficial practice. Secondly, the relative cost of information is modeled for individual update strategies in a novel way of framing a game by introducing a two-strategy and 2 (information state A/UA) by 2(healthy/infected) state game, referred to as a two-under-two game. In this framework, susceptible, infected, and vaccinated individuals are divided into two states as unaware and aware, and recovered individuals are assumed to be aware, for an unbounded and well-mixed population. Information about wearing masks or taking other protection against diseases spreads locally for a season, and this information has a significant tendency to reduce the extent of contagious disease that persists through each generation of the model. Mathematical analysis shows that funds spent on awareness can reduce the vaccination cost and improve the epidemic threshold under certain conditions..
8. Keisuke Nagashima, Jun Tanimoto, A stochastic Pairwise Fermi rule modified by utilizing the average in payoff differences of neighbors leads to increased network reciprocity in spatial prisoner's dilemma games, Applied Mathematics and Computation, 10.1016/j.amc.2019.05.034, 361, 661-669, 2019.11, In a 2 × 2 prisoner's dilemma (PD) game, network reciprocity is one of the mechanisms for increasing social viscosity, which leads to a cooperative equilibrium. The Pairwise Fermi (PW-Fermi) rule has been accepted as an updating protocol, as its stochasticity is similar to the real-world human decision-making process. In this paper, we elucidated a modification to the PW-Fermi rule by utilizing the averaged payoff difference instead of the simple payoff difference between a focal agent and their neighbors. This led to a significantly enhanced level of network reciprocity. The mechanism of this enhancement is clarified by discussing the concepts of the enduring period (END) and the expanding period (EXP)..
9. Ajaya ketan Nayak, Aya Hagishima, Jun Tanimoto, A simplified numerical model for evaporative cooling by water spray over roof surfaces, Applied Thermal Engineering, 10.1016/j.applthermaleng.2019.114514, 165, 2020.01, Evaporative cooling is a well-known passive technique adopted especially in hot and dry climatic regions. This paper presents a simplified numerical model to assess the impact of water spray over roof surfaces on the building thermal load. First, we performed a series of long-term outdoor measurements of heat fluxes from an asphalt pavement and roof top of a laboratory building waterproofed by asphalt sheet. Based on the measured data, a correlation is proposed to estimate the evaporation rate of the concerned surfaces after rain showers. A simplified numerical model is then developed using this correlation based on the unsteady heat transfer to analyze the effect of precipitation and artificial water spray on the roof of the laboratory building. Simulation is performed with the help MATLAB using the hourly weather data from Fukuoka, Japan, and the simulated results are found to be in correspondence with the measured data. Finally, the cooling effect achieved by varying the amount and rate of water spray over the roof is compared to find out the optimum spraying conditions. The novelty of this study is that, in this model, the evaporation rate can be expressed in terms of the evaporation ratio, which is defined as a function of the water content of the surface layer of the roof. The water content of the surface layer can be obtained by the water balance equation, which is coupled dynamically with conductive equations. This procedure can drastically reduce the calculation load compared to the conventionally applied simultaneous hygrothermal transfer equation..
10. Masaki Tanaka, Jun Tanimoto, Is subsidizing vaccination with hub agent priority policy really meaningful to suppress disease spreading?, Journal of Theoretical Biology, 10.1016/j.jtbi.2019.110059, 486, 2020.02, A Multi Agent Simulation (MAS) model that joins evolutionary game theory with epidemiological dynamics is established. Various subsidy policies that encourage vaccination are evaluated quantitatively with the model. The underlying social network topology is based on a scale-free network. Individual subsidies for vaccinations can be directed to hub agents with priority, to efficiently suppress the overall social cost of a vaccination program. These hub agents are more likely to spread both knowledge about vaccination and the disease in question. Our comprehensive simulations showed that this intuitively appealing strategy cannot be effective if the vaccination cost is low and the vaccination budget is small. Thus, we find that the hub agent priority strategy is not always effective..
11. Kazuki Kuga, Jun Tanimoto, Which is more effective for suppressing an infectious disease
Imperfect vaccination or defense against contagion?, Journal of Statistical Mechanics: Theory and Experiment, 10.1088/1742-5468/aaac3c, 2018, 2, 2018.02, We consider two imperfect ways to protect against an infectious disease such as influenza, namely vaccination giving only partial immunity and a defense against contagion such as wearing a mask. We build up a new analytic framework considering those two cases instead of perfect vaccination, conventionally assumed as a premise, with the assumption of an infinite and well-mixed population. Our framework also considers three different strategy-updating rules based on evolutionary game theory: conventional pairwise comparison with one randomly selected agent, another concept of pairwise comparison referring to a social average, and direct alternative selection not depending on the usual copying concept. We successfully obtain a phase diagram in which vaccination coverage at equilibrium can be compared when assuming the model of either imperfect vaccination or a defense against contagion. The obtained phase diagram reveals that a defense against contagion is marginally inferior to an imperfect vaccination as long as the same coefficient value is used. Highlights - We build a new analytical framework for a vaccination game combined with the susceptible-infected-recovered (SIR) model. - Our model can evaluate imperfect provisions such as vaccination giving only partial immunity and a defense against contagion. - We obtain a phase diagram with which to compare the quantitative effects of partial vaccination and a defense against contagion..
12. Yoshiro Iwamura, Jun Tanimoto, Complex traffic flow that allows as well as hampers lane-changing intrinsically contains social-dilemma structures, Journal of Statistical Mechanics: Theory and Experiment, 10.1088/1742-5468/aaa8ff, 2018, 2, 2018.02, To investigate an interesting question as to whether or not social dilemma structures can be found in a realistic traffic flow reproduced by a model, we built a new microscopic model in which an intentional driver may try lane-changing to go in front of other vehicles and may hamper others' lane-changes. Our model consists of twofold parts; cellular automaton emulating a real traffic flow and evolutionary game theory to implement a driver's decision making-process. Numerical results reveal that a social dilemma like the multi-player chicken game or prisoner's dilemma game emerges depending on the traffic phase. This finding implies that a social dilemma, which has been investigated by applied mathematics so far, hides behind a traffic flow, which has been explored by fluid dynamics. Highlight - Complex system of traffic flow with consideration of driver's decision making process is concerned. - A new model dovetailing cellular automaton with game theory is established. - Statistical result from numerical simulations reveals a social dilemma structure underlying traffic flow. - The social dilemma is triggered by a driver's egocentric actions of lane-changing and hampering other's lane-change..
13. Nurizzatul Atikha Rahmat, Aya Hagishima, Naoki Ikegaya, Jun Tanimoto, Experimental study on effect of spires on the lateral nonuniformity of mean flow in a wind tunnel, Evergreen, 10.5109/1929670, 5, 1, 1-15, 2018.03, The present work discusses in detail the experimental settings to establish a thick artificially generated urban-like atmospheric boundary layer in a short-fetch-length wind tunnel. It summarizes the comprehensive review of past studies on the flow behind quarter-elliptic-wedge spires, and clarifies the current issue of the spire setting in a wind tunnel experiment. This study investigates the persistent spanwise heterogeneity, the spatial structures of the flow past a row of quarter-elliptic-wedge spires, the streamwise distance required for a wake of elliptic-wedge spires to naturally recover, and how the mean flow changes farther downstream. Two experimental conditions were implemented in the present work (without and with spires) to analyse the effect of mean flow heterogeneity both within and above boundary layer height (BLH) regions, developing over a smooth wall that was produced by the installation of a flat plate on the wind tunnel floor..
14. Ryo Matsuzawa, Jun Tanimoto, Sanctions triggered by jealousy help promote the cooperation in spatial prisoner's dilemma games, Chaos, solitons and fractals, 10.1016/j.chaos.2018.03.029, 110, 239-243, 2018.05, Human beings have a natural tendency to feel jealous of those who have more than themselves. A previous report found that harmful behavior stemming from jealousy can actually encourage cooperation. The present study considers the efficiency of jealousy-motivated sanctions and the appropriate balance of sanctions and enforcement costs to best encourage cooperation. Through a series of numerical simulations of a spatial prisoner's dilemma game, we find that in the case of a lattice population structure, stronger sanctions and higher sanction efficiency ultimately result in more robust cooperation. In contrast, in the case of a scale-free population structure, higher sanction costs cause the cooperation level to rise..
15. Yuki Murakami, Naoki Ikegaya, Aya Hagishima, Jun Tanimoto, Coupled simulations of indoor-outdoor flow fields for cross-ventilation of a building in a simplified urban array, Atmosphere, 10.3390/atmos9060217, 9, 6, 2018.06, Computational fluid dynamics simulations with a Reynolds-averaged Navier-Stokes model were performed for flow fields over a building array and inside a building in the array with different building opening positions. Ten combinations of opening locations were selected to investigate the effect of the locations on indoor cross-ventilation rates. The results of these simulations show that the exterior distributions of mean wind speed and turbulence kinetic energy hardly differ even though building openings exist. Although similar patterns of outdoor flow fields were observed, the opening positions produced two different types of ventilations: one-way and two-way. In one-way ventilation, the wind flows through the opening are unidirectional: diagonally downward at the windward wall. In two-way ventilation, both inflow and outflow simultaneously occur through the same opening. Determination of ventilation rates showed that the ventilation types can explain what type of ventilation rate may be significant for each opening location..
16. Muntasir Alam, Keisuke Nagashima, Jun Tanimoto, Various error settings bring different noise-driven effects on network reciprocity in spatial prisoner's dilemma, Chaos, solitons and fractals, 10.1016/j.chaos.2018.07.014, 114, 338-346, 2018.09, In view of stochastic resonance effect, this paper reports what type of additional noise can draw more enhanced network reciprocity in spatial prisoner's dilemma (SPD) games presuming different underlying networks as well as strategy updating rules. Relying on a series of simulations comprehensively designed, we explored various noise models namely action error, copy error, observation error, by either placing random agents or biased agents and variant settings of those. We found that the influence by adding noise significantly differs depending on the type of noise as well as the combination of what underlying network and update rule are presumed. Action error when added to SPD games presuming deterministic updating rule shows relatively large enhancement for cooperation..
17. Jun Tanimoto, Ken Ichi Kimura, Simulation study on an air flow window system with an integrated roll screen, Energy and Buildings, 26, 3, 317-325, 1997, A numerical calculation procedure for an air flow window (AFW) system integrated with a roll screen is presented. Both heat and airflows within the window elements such as the outside pane of glass, the outside air space, a venetian blind, the inside air space and a roll screen, are taken into account by considering the thermal and air flow networks. Agreements between measured and calculated results of temperatures and pressure differences through a series of experiments carried out in an environmental test chamber were observed. To identify the quantitative characteristics of an AFW integrated with a roll screen, a series of numerical simulations were performed with the results from using a large resistance to the air flow from the upper half area of the roll screen. These show that this was effective in terms of thermal characteristics and suggest that a tightly-meshed roll screen, situtated in the upper half area, is suitable for both environmental and design reasons. If the heated air flow generated from the inside air space to the room were dispersed properly, the thermal efficiency of the AFW integrated with a roll screen would be equal to a conventional AFW system. The effect of a cold draft passing though the roll screen is also discussed..
18. Ping He, Tadahisa Katayama, Tetsuo Hayashi, Jun Ichiro Tsutsumi, Jun Tanimoto, Izuru Hosooka, Numerical simulation of air flow in an urban area with regularly aligned blocks, Journal of Industrial Aerodynamics, 67-68, 281-291, 1997.04, Numerical simulation of air flow distribution in a built-up area is an effective way to analyze and predict the urban thermal environment. A cyclic boundary conditions method for the numerical simulation of air flow around a block is used to model the unlimited spread of a built-up area. An equation for the calculation of the pressure difference between the windward and the leeward boundaries is proposed. Another simulation model which has 10 blocks aligned with the wind direction is used for comparison. The inflow boundary conditions are given by a wind tunnel test. The cyclic boundary conditions produced stable calculation results. The simulation results of the cyclic boundary conditions model are similar to those of the 10-block model in the cavity space. There is, however, a little difference between the results of these two models, and between them and the wind tunnel test in the higher area above the cavity and at the crossing point of the streets..
19. Haruyuki Fujii, Jun Tanimoto, Exploration in Complex Systems for Environmentally Symbiotic and Sustainable Society, Journal of Asian Architecture and Building Engineering, 10.3130/jaabe.2.107, 2, 1, 107-113, 2003, The authors assume that it is necessary to find a set of solutions to the crucial issues concerning the relation between the global environment and the sustainable human society. Based on the assumption, the authors have been developing man-environment-society system models to simulate the characteristic phenomena related to the issue. This paper describes one of the models focusing on a social dilemma that actions rationally performed to make individual’s indoor thermal environment better bring about worse environment against the rational decision. Some results of the case study simulations with the purpose to find some crews to deal with the issues are also shown..
20. Aya Hagishima, Jun Tanimoto, Field measurements for estimating the convective heat transfer coefficient at building surfaces, Building and Environment, 10.1016/S0360-1323(03)00033-7, 38, 7, 873-881, 2003.01, To establish a comprehensive and qualitative prediction basis for the convective heat transfer coefficient (CHTC) for various urban canopy surfaces mainly consisting of building envelopes, a series of outdoor experiments were performed. Multi-point measurements of surface heat balance lead to a distribution of the CHTC on an actual building envelope. Several turbulent statistical values acquired at two different sites enabled the development of an experimental equation depicted by non-dimensional numbers that express a relationship between CHTC and wind velocity containing a turbulent factor. An important thing is the fact that the two measuring sites, one a rooftop slab and the other the vertical wall of a test dwelling, have different scales and different surface directions facing the wind..
21. Jun Tanimoto, Haruyuki Fujii, A study on diffusional characteristics of information on a human network analyzed by a Multi-Agent simulator, Social Science Journal, 10.1016/S0362-3319(03)00045-4, 40, 3, 479-485, 2003.01, A mathematical frame to deal with the Face-to-Face Word of Mouth Communication (WOMC) and the Network WOMC was obtained, respectively. The difference between two types of WOMC is how the information can be conveyed. In the former type, information goes through the real human contact, which can be understood as on-site-communication. To the contrary, in the later, information can leap to remote places passing through the acquaintance network provided by telecommunication such as cellular phone and e-mail. For practical calculation, a program on the platform of the Multi-Agent type simulation was developed. Using this, a numerical experiment was done to reveal fundamental characteristics of both the Face-to-Face and Network WOMC..
22. Aya Hagishima, Ken Ichi Narita, Jun Tanimoto, Field experiment on the oasis effect of urban areas using potted plants, 5th Symposium on the Urban Environment 5th Symposium on the Urban Environment, 243-245, 2004, An experimental study, using potted plants was, conducted to estimate the oasis effects of urban areas. The study for 28 days shows that evaporation rate of an isolated plant is one-and-half times larger than that of plant placed in the center of a dense canopy. The experiment was accompanied by noting the evaporation rate of 55 potted plants, arranged at an interval of 3.6 meters. It was observed that evaporation rate increased with an decrease in the vegetation density..
23. Aya Hagishima, Jun Tanimoto, Ken Ichi Narita, Comparisons of various experimental results on the convective heat transfer coefficient of urban surfaces, 5th Symposium on the Urban Environment 5th Symposium on the Urban Environment, 647-648, 2004, A comparative study on experimental results obtained on the convective heat transfer coefficients on urban surfaces are discussed. Convective heat transfer coefficient (CHTC) was considered to express the turbulent heat exchange between the atmosphere and urban surfaces. A detailed study on relationship between CHTC of vertical wall of buildings and wind speeds, and CHTC for horizontal building roofs and wind speeds, was also presented. It was observed that position of walls has relatively large influence on CHTC..
24. Haruyuki Fujii, Jun Tanimoto, Integration of building simulation and agent simulation for exploration to environmentally symbiotic architecture, Building and Environment, 10.1016/j.buildenv.2004.01.013, 39, 8 SPEC. ISS., 885-893, 2004.01, A method of simulating the interaction between architectural environment and human action in the environment is described. The computational model consists of a model for building simulation, a model for action simulation, and a model to mediate the simulation models. This model is being developed to find the environmentally symbiotic actions and the knowledge and beliefs that people are encouraged to acquire to perform such actions. It might not be possible for the majority of traditional simulation to model an occupant as the individual having desire, belief, and intention. The proposed model may provide a solution to complement the disadvantage..
25. Jun Tanimoto, Aya Hagishima, Parichart Chimklai, An approach for coupled simulation of building thermal effects and urban climatology, Energy and Buildings, 10.1016/j.enbuild.2004.01.019, 36, 8, 781-793, 2004.08, The computer software AUSSSM TOOL, originating from the methodology of the revised-architectural-urban-soil-simultaneous simulation model (revised-AUSSSM), was developed by adopting the graphical user interface (GUI) features to support users, who can use the interactive computer display for parameter settings, simulating, visualizing, and reporting the numerical calculation results instead of complicated programming. The purpose of the AUSSSM TOOL is to determine quantitative parameters such as air temperature, exhaustive heat from air conditioning systems, energy heat balance, etc. within the urban canopy structure, which data enables the evaluation of effects of urban heat island (UHI) in concrete terms useful to urban planners, architects, engineers, and so forth in the field of urban climatology involving building scale. In addition to conducting a full numerical simulation, in order to simplify a comparison among complex factors influencing UHI, numerical experiments based on Taguchi design of experiment theory (DOE) were carried out. The results of the numerical experiments were stored in a database and ready to be instantly grasped by any inexperienced user corresponding to their specified conditions. This paper describes the fundamental method of the revised-AUSSSM, the objectives of related software development, and the structures of the AUSSSM TOOL and the techniques comprising its algorithm to present the numerical simulation results in particular..
26. Parichart Chimklai, Aya Hagishima, Jun Tanimoto, A computer system to support Albedo Calculation in urban areas, Building and Environment, 10.1016/j.buildenv.2004.02.006, 39, 10, 1213-1221, 2004.10, The Albedo Calculation Model (ACM) has been developed to provide the simulation of albedos within three-dimensional urban structures. The model takes into account urban configurations and a change of solar positions, as well as the effects of multiple reflections and shading in an urban canopy. In order to perform a systematic analysis for the effect of various factors on albedo of surfaces, a large scale numerical experiment has been conducted. The model description and experiment results of albedo characteristics are clarified in this paper. In addition, the development of two associated GUI (graphical user interface)-based applications, Albedo Calculator and Albedo Viewer is also introduced..
27. Jun Tanimoto, Aya Hagishima, Hiroki Sagara, Cooling looad simulation considering actual variation of inhabitants' behavior inhabitants' behavior for accurate estimation of urban maximum energy requirement, Building Simulation 2005 - 9th International IBPSA Conference, BS 2005 IBPSA 2005 - International Building Performance Simulation Association 2005, 1205-1212, 2005, A brand-new methodology for considerably accurate time-series cooling load calculation in a dwelling is established, motivated by the fact that dwelling energy requirements so significantly affect the so-called urban heat island. Calculation that takes variation among dwelling-inhabitants' behaviors into consideration appears to be important. The proposed method contains two crucial features. The first is a procedure for cooling load calculation based on a series of Monte Carlo simulations where HVAC on/ off state and indoor heat generation schedule are variable time-step by time-step. The second feature is an algorithm to generate myriad schedule data of each inhabitant's behavior that must be provided with fine time resolution..
28. Jun Tanimoto, Environmental dilemma game to establish a sustainable society dealing with an emergent value system, Physica D: Nonlinear Phenomena, 10.1016/j.physd.2004.09.016, 200, 1-2, 1-24, 2005.01, To induce whether we can obtain a sustainable society by shifting our paradigm from the materialistic to the eco-conscientious, we established a multi-agent simulation model. The model primarily featured a dilemma structure encouraged by a conflict between each agent's private desire to earn more and the need for environmental conservation. Another important feature is that the model has two evolutionary layers. The subordinate layer is a learning system comprised of a finite state machine (FSM) and a genetic algorithm (GA) primarily, which is carried with each individual agent to determine his/her next behavior and how much he/she must earn to maximize an individual fitness function. The supra layer is the so-called value system, the gene pool of which is shared within the society. The value system stipulates an agent's fitness function, which in turn affects the agent's behavior. The value system of each agent was set up to be entirely ego-oriented at the beginning of the simulation episode. A numerical experiment based on the model reveals a scene in which, under a certain condition related to assumptions of the value system, a group of agents undergoes a paradigm shift from the ego-oriented materialism to the eco-conscious sustainable society. The key condition is a latent existence of several values that ultimately lead to sustainability, even though they do not work at all at the beginning of the episode. In terms of the evolutionary game theory, this implies that changing game structure on the way of a simulation episode by transforming the fitness function seems to be much powerful measures for the emergent collective cooperation among the agents than ordinal options to support cooperation. In addition, we made a detailed analysis on how assumed agents have obtained a sustainable value system. Each agent has an individual decision-making process based on the input with a learning mechanism. We focus here on two types of learning system, the finite state machine (FSM) plus genetic algorithm (GA), and profit shearing (PS). Observation of the generative trails of FSM and the value table of PS lead us to a profound understanding of what kind of inception triggers the emergence of a sustainable society..
29. Jun Tanimoto, Aya Hagishima, State transition probability for the Markov Model dealing with on/off cooling schedule in dwellings, Energy and Buildings, 10.1016/j.enbuild.2004.02.002, 37, 3, 181-187, 2005.03, We gathered field measurement data on five familial and three single dwellings during summer 2000 by deploying numerous handy type hygrothermal meters with self-recording functions to measure room air, globe and outdoor air temperatures. These measurements led to conclusions on the probability of turning on an air conditioning system versus indoor globe temperature and the ongoing probability of air conditioning versus outdoor temperature. This analysis was transformed into state transition probability functions, i.e. shifting from the off to on state and from the on to off state. Identifying these state transition probability functions is an important first step in applying the Markov Model to on/off state analysis for air conditioning systems, which is one of the significant approaches for dealing with the stochastic thermal load for HVAC system. The obtained state transition probability functions should help immeasurably in determining effective schedules for air conditioning operation from inhabitant occupancy schedules..
30. Aya Hagishima, Jun Tanimoto, Investigations of urban surface conditions for urban canopy model, Building and Environment, 10.1016/j.buildenv.2004.08.010, 40, 12, 1638-1650, 2005.12, The authors carried out several investigations to clarify the features of urban surface conditions in the urban canopy Model (UCM). The authors first conducted field investigations regarding the solar reflectance of urban surfaces. First, the wall reflectance and the proportion of the glazing area were measured in several urban areas. The relationship between the solar reflectance of road and traffic density is clarified based on the outdoor measurement and the field survey. It is also presented that the reflectance of the building rooftop varies significantly depending on building use and the influence of machinery in the area of the HVAC. The authors secondly investigated the height of released anthropogenic heat from the HVAC system based on a field survey and a database of HVAC systems provided by certain journals. From these investigations, it is presented that the type of HVAC system and the height of released anthropogenic heat vary with the building scale. Finally, an investigation of urban geometric figures was conducted using GIS data from Tokyo and Fukuoka in Japan. The vertical distribution features of both the roughness volume density and the building wall area density were classified according to the gross ratio of building volume..
31. Aya Hagishima, Jun Tanimoto, Ken Ich Narita, Intercomparisons of experimental convective heat transfer coefficients and mass transfer coefficients of urban surfaces, Boundary-Layer Meteorology, 10.1007/s10546-005-2078-7, 117, 3, 551-576, 2005.12, The convective heat transfer coefficient (CHTC) of an urban canopy is a crucial parameter for estimating the turbulent heat flux in an urban area. We compared recent experimental research on the CHTC and the mass transfer coefficient (MTC) of urban surfaces in the field and in wind tunnels. Our findings are summarised as follows. (1) In full-scale measurements on horizontal building roofs, the CHTC is sensitive to the height of the reference wind speed for heights below 1.5 m but is relatively independent of roof size. (2) In full-scale measurements of vertical building walls, the dependence of the CHTC on wind speed is significantly influenced by the choice of the measurement position and wall size. The CHTC of the edge of the building wall is much higher than that near the centre. (3) In spite of differences of the measurement methods, wind-tunnel experiments of the MTC give similar relations between the ratio of street width to canopy height in the urban canopy. Moreover, this relationship is consistent with known properties of the flow regime of an urban canopy. (4) Full-scale measurements on roofs result in a non-dimensional CHTC several tens of times greater than that in scale-model experiments with the same Reynolds number. Although there is some agreement in the measured values, our overall understanding of the CHTC remains too low for accurate modelling of urban climate..
32. Yuemei Zhu, Jing Liu, Yang Yao, Zuiliang Ma, Aya Hagishima, Jun Tanimoto, Evaluating the impact of solar radiation on outdoor thermal comfort by the development and validation of a simple urban climatic model, ASME International Solar Energy Conference - Solar Engineering 2006 Proceedings of the ASME International Solar Energy Conference - Solar Engineering 2006, 2006, 2006, In this paper, in order to predict the outdoor thermal environment, a simple multi-layer canopy model coupled with calculation of outdoor thermal comfort was developed. SET* value was used to estimate the pedestrian level of thermal comfort in the outdoor thermal environment. Preliminary verification of this model using observational data on the outdoor thermal conditions showed good results. In addition, the results show that outdoor thermal comfort is significantly different with air temperature. Except for air temperature, both solar radiation and humidity play important roles on outdoor thermal comfort..
33. Yuemei Zhu, Jing Liu, Yang Yao, Zuiliang Ma, Aya Hagishima, Jun Tanimoto, Evaluating the impact of solar radiation on outdoor thermal comfort by the development and validation of a simple urban climatic model, Solar 2006: Renewable Energy - Key to Climate Recovery, Including 35th ASES Annual Conference, 31st ASES National Passive Solar Conference, 1st ASES Policy and Marketing Conference and ASME Solar Energy Division International Solar Energy Conference American Solar Energy Society - Solar 2006: 35th ASES Annual Conf., 31st ASES National Passive Solar Conf., 1st ASES Policy and Marketing Conf., ASME Solar Energy Division Int. Solar Energy Conference, 3, 1522-1528, 2006, In this paper, in order to predict the outdoor thermal environment, a simple multilayer canopy model coupled with calculation of outdoor thermal comfort was developed. SET* value was used to estimate the pedestrian level of thermal comfort in the outdoor thermal environment. Preliminary veri cation of this model using observational data on the outdoor thermal conditions showed good results. In addition, the results show that outdoor thermal comfort is significantly different with air temperature. Except for air temperature, both solar radiation and humidity play important roles on outdoor thermal comfort..
34. Jun Tanimoto, Aya Hagishima, Hiroki Sagara, Validation of the probabilistic methodology to generate actual inhabitants' behavior schedules for accurate prediction of maximum energy requirement, Building Simulation 2007, BS 2007 IBPSA 2007 - International Building Performance Simulation Association 2007, 696-702, 2007, A data set of myriad and time-varying inhabitant-behavior schedules with a 15-minute time resolution, generated by the authors in a previous study, is validated through a comparison analysis. We show three comparisons. The first and second compare the estimated demand with a time series of actual utility demand. The comparisons indicate that the generated data and its algorithm, described by the authors, have an appropriate robustness. Another comparison between the estimate and the annual averaged daily water demand of a residential area, consisting of 9,327 residences, also shows an acceptable consistency..
35. Yuemei Zhu, Jing Liu, Yang Yao, Zuiliang Ma, Aya Hagishima, Jun Tanimoto, Evaluating the impact of solar radiation on outdoor thermal comfort by the development and validation of a simple Urban climatic model, 2006 International Solar Energy Conference, ISEC2006 Proceedings of the ASME International Solar Energy Conference, ISEC2006, 10.1115/ISEC2006-99012, 515-521, 2007, In this paper, in order to predict the outdoor thermal environment, a simple multi-layer canopy model coupled with calculation of outdoor thermal comfort was developed. SET* value was used to estimate the pedestrian level of thermal comfort in the outdoor thermal environment. Preliminary verification of this model using observational data on the outdoor thermal conditions showed good results. In addition, the results show that outdoor thermal comfort is significantly different with air temperature. Except for air temperature, both solar radiation and humidity play important roles on outdoor thermal comfort..
36. Hiroki Sagara, Jun Tanimoto, A study on social diffusive impacts of a novel car-navigation-system sharing individual information in urban traffic systems, 2007 IEEE Congress on Evolutionary Computation, CEC 2007 2007 IEEE Congress on Evolutionary Computation, CEC 2007, 10.1109/CEC.2007.4424557, 836-842, 2007, As one of the authors' trials to establish a model for human-environment- social Systems, a multi-agent simulation model to deal with urban traffic congestion problems involving automobiles embedded with several strategies of car navigation systems (CNS), has been presented. A shortest time route with route information sharing strategy (ST-RIS) is believed to be one of the solutions for a novel CNS based on bilateral information shared among automobile agents. The question of which strategy is most appropriate for solving urban traffic congestion can be seen as a social dilemma, since the social holistic utility is opposite to each agent's individual utility. The presented model shows that this social dilemma is observed as a typical Chicken type dilemma, or as a typical Minority Game, where an agent who has adopted a minority strategy can earn more utility than other strategies. Consequently, the model has illustrated that ST-pRIS, which is a further advanced strategic form of ST-RIS, where only partial information is shared among agents, has a moderate potential to be diffused in a society from the viewpoint of the evolutionary game theory..
37. Yuemei Zhu, Jing Liu, Aya Hagishima, Jun Tanimoto, Yang Yao, Zuiliang Ma, Evaluation of coupled outdoor and indoor thermal comfort environment and anthropogenic heat, Building and Environment, 10.1016/j.buildenv.2005.10.019, 42, 2, 1018-1025, 2007.02, With rapid urbanization, big cities in the south of China are progressively falling short of sustaining outdoor thermal comfort. In this paper, a thermal comfort and energy evaluation model is derived from revisions of previous study, to simulate and predict the interaction of coupled urban building-site climate and then the thermal comfort. The methodology of principal calculations is demonstrated first, then a hypothetical district of office buildings in Shanghai is selected. Dynamic on-site climate parameters, anthropogenic heat and indoor/outdoor SET* values, etc., are simulated and evaluated. The results show the variation of outdoor SET* values influenced by factors including canopy height, building coverage and air-conditioning set-point temperature..
38. Aya Hagishima, Ken Ich Narita, Jun Tanimoto, Field experiment on transpiration from isolated urban plants, Hydrological Processes, 10.1002/hyp.6681, 21, 9, 1217-1222, 2007.04, The effect of pot plant density on plant transpiration rate was examined in a series of field experiments. Three spatial densities were crated using 203 nearly homogeneous pot plants; the ratios of plant separation to plant height were 0.25, 0.5, and 3 for the 'high,' 'medium,' and 'low' groups respectively. The daily transpiration rate of 55 pot plants was measured for 28 days. During that period, the plants were randomly rotated each day to statistically eliminate individual characteristics and to successfully ascertain the effect of plant spatial density on the transpiration rate. As a best-case scenario, the soil for each plant was saturated at the start of each experiment. The results showed that the transpiration rate of potted plants in the 'low' group was about 1.5 times greater than that of the 'high' group. On the basis of the transpiration rate per unit of vegetation area projected on a horizontal plain, which is a general index used in meteorological modeling, the plants in the 'low' group evaporated 2.7 times as much water as those in the centre of the 'high' group. These results indicate the need for modified models that can consider the relative increase in evapotranspiration from vegetation in small-size plants or low spatial density of vegetation to estimate latent heat flux in urban areas..
39. Jun Tanimoto, Hiroki Sagara, Relationship between dilemma occurrence and the existence of a weakly dominant strategy in a two-player symmetric game, BioSystems, 10.1016/j.biosystems.2006.07.005, 90, 1, 105-114, 2007.07, Defining the dilemma game by the proposition, A game cannot sustain an increase of cooperation strategy in its strategy distribution, we deduced that the substance of a dilemma can be expressed by a productive summation of the static factor and the dynamic factor independently. A static factor is an element of the game's structure that influences a possible dilemma, which relates to a game's structural deviation from a situation where the cooperation strategy can be weakly dominant over other strategies. In contrast, a dynamic factor refers to a strategy distribution's influence on the dilemma by affecting the game dynamics. In a 2 × 2 game, the existence of a dilemma can be determined only by a static factor. That is, whether or not a dilemma occurs is related only to the structural effect of the game. On the other hand, in a more-than-two-strategies game, both static and dynamic factors determine the occurrence of a dilemma, and the static factor cannot solely explain the occurrence of a dilemma..
40. Jun Tanimoto, Does a tag system effectively support emerging cooperation?, Journal of Theoretical Biology, 10.1016/j.jtbi.2007.03.033, 247, 4, 756-764, 2007.08, This paper investigates whether the so-called Tag Systems support emerging cooperation with respect to 2×2 games. The Tag System, initially proposed by Riolo et al. [2001. Evolution of cooperation without reciprocity. Nature 414, 441-443], gives each agent both a Tag and Tol defined by [0,1] real numbers. Tol is a tolerance for recognizing an opponent as a company. Both Tag and Tol are assumed to be evolving. Results show that the tag's effectiveness depends on whether the AllD strategy is allowed in the system. Allowing AllD implies that green beard effect does not work in the system. Thus, (1) the tag's effectiveness is more meager than that reported by Riolo et al., (2) the Tag System can use alternating reciprocity more effectively than the analytic solution in a Hero game; (3) a system using a 2D tag space supports cooperation more effectively than the usual Tag System..
41. Jun Tanimoto, Dilemma solving by the coevolution of networks and strategy in a 2×2 game, Physical Review E - Statistical, Nonlinear, and Soft Matter Physics, 10.1103/PhysRevE.76.021126, 76, 2, 2007.08, A 2×2 game model implemented by a coevolution mechanism of both networks and strategy, inspired by the work of Zimmermann and Eguiluz [Phys. Rev. E72, 056118 (2005)] is established. Network adaptation is the manner in which an existing link between two agents is destroyed and how a new one is established to replace it. The strategy is defined as whether an agent offers cooperation (C) or defection (D). Both the networks and strategy are synchronously renovated in a simulation time step. A series of numerical experiments, considering various 2×2 game structures, reveals that the proposed coevolution mechanism can solve dilemmas in several game classes. The effect of solving a dilemma means mutual-cooperation reciprocity (R reciprocity), which is brought about by emerging several cooperative hub agents who have plenty of links. This effect can be primarily observed in game classes of the prisoner's dilemma and stag hunt. The coevolution mechanism, however, seems counterproductive for game classes of leader and hero, where the alternating reciprocity (ST reciprocity) is meaningful..
42. Jun Tanimoto, Differences in dynamics between discrete strategies and continuous strategies in a multi-player game with a linear payoff structure, BioSystems, 10.1016/j.biosystems.2006.12.008, 90, 2, 568-572, 2007.09, A deductive analysis concerning replicator dynamics proved that a continuous strategy game (in which a player chooses an arbitrary real number between [0, 1] as a cooperative fraction) has the same equilibrium as a discrete strategy game (in which a player chooses only C or D), which has the same linear payoff structure as a continuous strategy game. The deduction is shown for two-player and multi-player games..
43. Jun Tanimoto, Promotion of cooperation by payoff noise in a 22 game, Physical Review E - Statistical, Nonlinear, and Soft Matter Physics, 10.1103/PhysRevE.76.041130, 76, 4, 2007.10, A series of numerical simulations of a 22 symmetric game on a network examined whether payoff matrix noise promotes cooperation, as reported initially by Perc [New J. Phys. 8, 22 (2006)]. Agents have no memory (they offer cooperation, C, or defection, D). We assume that the network is time invariable. The effect of payoff matrix noise (PMN) is measured by a simulated payoff difference between a normal network game and a network game with PMN. The effect of PMN appears only when a local strategy adaptation is implemented (for example, a network game with imitation dynamics). The influence of PMN becomes more significant with a larger stochastic deviation, and less significant in a larger degree network. One reason for PMN’s effectiveness is the local strategy adaptation mechanism, which helps both the preservation and fixation of C agents, and not that the payoff matrix noise makes a dilemma game into a Trivial (dilemma-free) game..
44. Jun Tanimoto, Hiroki Sagara, A study on emergence of alternating reciprocity in a 2 × 2 game with 2-length memory strategy, BioSystems, 10.1016/j.biosystems.2007.03.001, 90, 3, 728-737, 2007.11, It is recognized that bilateral cooperation (C), a reward-state in other words, emergently comes up in a 2 × 2 prisoner's dilemma game, if you assume a strategy set with a memory concept. Also observed is a mixture state of cooperation (C) and defect (D), saint- and temptation-state in other words, to obtain a higher payoff than R (R reciprocity) in a hero or leader game that is a chicken-type dilemma game; this phenomenon is called alternating reciprocity (AR) or ST reciprocity. Observing a holistic 2 × 2 game world including trivial games and various dilemma games, where 2-length memory and infinite interactions are assumed, the paper reports on the specific mechanism of AR. It is observed there are three different phases relating to AR, which can be explained by the stress of the dilemma..
45. Jun Tanimoto, A study of indirect reciprocity involving a reputation system or a simple tag system in a one-shot, multi-player game, BioSystems, 10.1016/j.biosystems.2007.05.002, 90, 3, 856-869, 2007.11, The possibility of the evolution of cooperation backed by indirect reciprocity (IDR) in a one-shot, multi-player game is investigated focusing on two mechanisms. First of all, the reputation system with image score (RS with IS), as proposed by Nowak and Sigmund [Nowak, M.A., Sigmund, K., 1998. Evolution of indirect reciprocity by image scoring. Nature 393, 573-577], is investigated in various game structures. A numerical experiment demonstrates that the RS with IS is a robust mechanism for the support of IDR in various dilemma games, but whose effectiveness decreases with an increase in the number of players in a game. It is fair to say that the RS is an information mapping function to relate between player's cooperative fraction on his action and IS. As the second mechanism, a simple tag system which could be applicable to animals having no cognitive complexity is considered to support IDR. Computer simulations of the tag system's strategy for invading a population initially consisting of AllD, AllC, and Random strategies suggest several novel facts. The Tag strategy with plausible crossover and mutation probabilities can only invade to settle down if the game structure is not Trivial and contains a moderate dilemma. The Tag strategy's evolutionary competition takes place mainly in the presence of the AllD strategy. During the competition, the Tag strategy frequently metamorphoses to shake off the AllD strategy, but stops after winning in order to avoid a shrinking payoff due to fragmentation..
46. Jun Tanimoto, Emergence of cooperation supported by communication in a one-shot 2 × 2 game, 2007 IEEE Congress on Evolutionary Computation, CEC 2007 2007 IEEE Congress on Evolutionary Computation, CEC 2007, 10.1109/CEC.2007.4424631, 1374-1381, 2007.12, This paper reports an intelligent agent equipped with 2-layer finite state machines (FSM) that can communicate by turning lighting on and off, leading to social cooperation that solves the dilemma situation, modeled by a one-shot 2 × 2 game. This communication between two gaming agents can be observed in Hero- and Leader-type dilemma games, where alternating reciprocity, repeating cooperation (C)-defeat (D) after D-C, is the equal Pareto Optimum instead of a sequence of mutual cooperation that is the equal Pareto Optimum for a Prisoner's Dilemma (PD) game. This implies that what initially brought about animal communications is not the dilemma situation emulated by PD, but a Hero or Leader type game..
47. Naoki Ikegaya, Jun Tanimoto, Aya Hagishima, Hiroki Sagara, A study on multi-agent simulation model for transient dynamics and distribution of the population in an urban area, AIJ Journal of Technology and Design, 10.3130/aijt.13.845, 13, 26, 845-848, 2007.12, In order to reproduce both transient dynamics and space distribution of an urban population only derived from a simple self-organism principle, a multi-agent simulation model is established. A resident agent tries to move to a cell so as to maximize his own utility that is defined by both effects of distance from the urban central and population density. The so-called "doughnut phenomenon" as well as growing Densely Inhabited District (DID) can be emulated qualitatively, even though the model bases on a simple self-organism rule..
48. Jun Tanimoto, Aya Hagishima, Hiroki Sagara, Validation of probabilistic methodology for generating actual inhabitants' behavior schedules for accurate prediction of maximum energy requirements, Energy and Buildings, 10.1016/j.enbuild.2007.02.032, 40, 3, 316-322, 2008, A data set of myriad and time-varying inhabitant-behavior schedules with a 15 min time resolution, generated by the authors in a previous study, is validated through a comparison analysis. We show three comparisons. The first and second compare the estimated demand with a time series of actual utility demand. The comparisons indicate that the generated data and its algorithm, described by the authors, have an appropriate robustness. Another comparison between the estimate and the annual averaged daily water demand of a residential area, consisting of 9327 residences, also shows an acceptable consistency..
49. Jun Tanimoto, Emergence of cooperation in patchy habitat with mortality and colonization based on various 2 × 2 games, Sociobiology, 52, 1, 185-206, 2008, A multi-agent simulation model emulating the dynamic processes of an animal species' patchy habitat with mortality and colonization was established. The model, revised from Zhang et al. (2005), can deal with a variety of 2 × 2 game structures including the Prisoner's Dilemma (PD). When a higher mortality is assumed, the defect-agent fraction considerably decreases in a game structure with heavy dilemma (including the PD). This is because agents try to survive by forming cooperative clusters (C-cluster) to overcome the dilemma. This implies that cooperation easily emerges when the mortality process is more influential on the agent's adaptation than colonization, which seems consistent with Hauert's (2006) study. This situation increases the fraction of cooperative agents against the empty fraction in a larger number of link structures, which can easily build a C-cluster..
50. Jun Tanimoto, Co-evolution model of networks and strategy in a 2 × 2 game emerges cooperation, 2008 IEEE Congress on Evolutionary Computation, CEC 2008 2008 IEEE Congress on Evolutionary Computation, CEC 2008, 10.1109/CEC.2008.4630785, 117-122, 2008, A 2×2 game model implemented by co-evolution of both networks and strategies Is established. Several numerical experiments considering various 2×2 game classes, including Prisoner's Dilemma (PD), Chicken, Leader, and Hero, reveal that the proposed co-evolution mechanism can solve dilemmas in the PD game class. The result of solving a dilemma is the development of mutual-cooperation reciprocity (R reciprocity), which arises through the emergence of several cooperative hub agents, which have many links in a heterogeneous and assortative social network. However, the co-evolution mechanism seems counterproductive in case of the Leader and Hero game classes, where alternating reciprocity (ST reciprocity) is more demanding. It is also suggested that the assortative and cluster coefficients of a network affect the emergence of cooperation for R reciprocity..
51. Jun Tanimoto, Aya Hagishima, Hiroki Sagara, Validation of methodology for utility demand prediction considering actual variations in inhabitant behaviour schedules, Journal of Building Performance Simulation, 10.1080/19401490701868471, 1, 1, 31-42, 2008.01, A data set of myriad and time-varying inhabitant behaviour schedules with a 15-min time resolution, generated by the authors in a previous study, is validated through a comparison analysis. The key idea of generating a set of raw schedule data from the restricted statistical information is called the ‘generate and kill’ concept, which is commonly used in the fields of artificial intelligence and multi-agent simulation. In the present study, we show three comparisons. The first and second compare the estimated demand with a time series of measured utility demand. These comparisons indicate that the generated data and the algorithm, as described by the authors, have the required robustness. Another comparison between the estimate and the annually averaged daily water demand of a residential area, consisting of 9327 residences, also shows an acceptable consistency..
52. Jun Tanimoto, What initially brought about communications?, BioSystems, 10.1016/j.biosystems.2007.12.001, 92, 1, 82-90, 2008.04, This paper reports an intelligent agent equipped with two-layer finite state machines (FSMs) that can communicate by turning lighting on and off, leading to social cooperation that solves the dilemma situation, modeled by a one-shot 2 × 2 game. This communication between two gaming agents can be observed in hero- and leader-type dilemma games, where alternating reciprocity, repeating cooperation (C)-defeat (D) after D-C, is the equal pareto optimum instead of a sequence of mutual cooperation that is the equal pareto optimum for a prisoner's dilemma (PD) game..
53. Aya Hagishima, Ken Ichi Narita, Hirofumi Sugawara, Jun Tanimoto, Field measurement on distribution of convective heat transfer coefficient within a real-scale urban canopy, Journal of Environmental Engineering (Japan), 10.3130/aije.73.511, 73, 626, 511-518, 2008.04, A field measurement on thermal balance and flow characteristics of a full-scale 2D canopy was done, and following phenomena were observed. 1) Air temperature distribution and sensible heat flux of canopy surfaces show the high irregularity due to the sunshade. 2) Linear relationships exist between wind speed Uim and convective heat transfer coefficient (CHTC) of most measurement points. The linear regressions of SAT meters fixed on a leeward wall show similar tendency, in contrast those on a windward wall vary with the position. This tendency is consistent with those of former wind tunnnel experiments. 3) CHTCs of walls deduced from measurement result of surface thermal balance show different tendency of those of SAT meters. It may be caused by the effect of the unhomogeneous temperature distribution of canopy..
54. Jun Tanimoto, Aya Hagishima, Hiroki Sagara, A methodology for peak energy requirement considering actual variation of occupants' behavior schedules, Building and Environment, 10.1016/j.buildenv.2006.06.034, 43, 4, 610-619, 2008.04, A novel methodology to accurately estimate the cooling demand in residential units is proposed, as a means of providing a better assessment of urban heat-island effects attributable to the use of residential air-conditioning units. The methodology integrates probabilistic variations in occupant behavior, which is shown to be a significant factor in estimated residential cooling requirements. The methodology consists of two key features. The first is an algorithm that generates short-term events that are likely to occur in a residential context, based on published data on occupant behavior. The second is a Monte Carlo approach to cooling load calculations based on stochastic variations in these short-term events and in the consequent likelihood of switching air-conditioning on or off..
55. Motoya Wakiyama, Jun Tanimoto, Hiroki Sagara, Aya Hagishima, A research on the universal model of environmental dilemma game based on 2x2 game constrained with the exogenous resource restriction
An influence of the social network on emerging possibility of the sustainable society part 2, Journal of Environmental Engineering (Japan), 10.3130/aije.73.831, 73, 628, 831-838, 2008.06, A universal model for the Environmental Dilemma Game is established. The model has two features. The first point is that the influence of the environment is treated as an exogenous resource restriction that has own dynamics, which is different from 2-players Chicken game or Tragedy of Commons (JV-players Chicken game). The second point is that the game playing among agents is based on various 2x2 games, not a particular game specifically aiming at a certain environmental problem. A series of simulations reveals that a sustainable strategy allowing behavior-shifting to adjust environmental capability has been evolved in several game structures. However, in most game structures, dangerous strategies always trying to obtain resources has been prevailed. Social locality affects to support emerging a sustainable society in some game structure, but in another game structure it devastates existing sustainable society..
56. Aya Hagishima, Jun Tanimoto, Satoru Suenaga, Naoki Ikegaya, Kazuyuki Maeda, Ken Ichi Narita, Wind tunnel experiment on bulk scalar coefficient of urban-like roughness, Journal of Environmental Engineering (Japan), 10.3130/aije.73.1225, 73, 632, 1225-1231, 2008.10, The authors investigated bulk scalar coefficient (CE) of the street in the 3-D canopy with various conditions of arrangement, plan area density (λp), frontal area index (λf), and variability of model height in a wind tunnel using salinity method. The results can be summarized as follows. 1) The relationships between CE and lf of both staggered and normal arrayed canopy with uniform height shows different tendency. The CE of 3-D canopy of staggered and normal pattern have similar value under the sparse (λf) and dense conditions, in contrast, CE of staggered canopy is higher than that of normal canopy under the condition of λf = 17.4%. 2) CE of uniform canopy is larger than that of canopy with height variation under the condition of λf < 17.4%. In contrast, CE of uniform canopy is smaller than that of canopy with height variation under the condition of λf = 30.9%. Such a tendency is opposite to the result of drag force coefficient..
57. Jun Tanimoto, Aya Hagishima, Total utility demand prediction based on probabilistically generated behaviroal schedules of actural inhabitants, 11th International IBPSA Conference - Building Simulation 2009, BS 2009 IBPSA 2009 - International Building Performance Simulation Association 2009, 521-528, 2009, This paper describes a new methodology in calculating accurately the time series utility loads (energy, power, city water, hot water, etc.) in a dwelling. This calculation takes into account the behavioral variations of the dwelling inhabitants. The proposed method contains a procedure for cooling load calculations based on a series of Monte Carlo simulations where the HVAC on/off state and the indoor heat generation schedules are varied, time-step by time-step. A data set of time-varying inhabitant behavior schedules, with a 15 minute resolution, generated by the authors in previous studies and validated by a comparison analysis to several field measurement data sets, was integrated into the model. The established model, which is called the Total Utility Demand Prediction System (TUD-PS) can be applied to, for example, accurate estimation of an integrated space maximum requirement, such as the total load of a building or an urban area. In a series of numerical experiments, huge discrepancies were found between the conventional results and those considering the time-varying inhabitant behavior schedules. In particular, deriving the dynamic state change, of having the HVAC on/off from the inhabitant's schedules, was found to be a significant factor in the maximum cooling and heating loads..
58. Jun Tanimoto, The effect of assortative mixing on emerging cooperation in an evolutionary network game, 2009 IEEE Congress on Evolutionary Computation, CEC 2009 2009 IEEE Congress on Evolutionary Computation, CEC 2009, 10.1109/CEC.2009.4982985, 487-493, 2009, A series of numerical experiments using a co-evolutionary model for both networks and strategies for 2 - 2 games was carried out. It was proven that there was an interesting relation between assortative mixing of the evolved network and emerging cooperation. In the Prisoner's Dilemma (PD) game class, the evolutionary trail for a weak dilemma game leads to an assortative mixing network, and attains cooperative situation easily. A game implemented with a stronger dilemma, however, makes the network very heterogeneous, featuring a negative assortative coefficient to solve the dilemma situation. This implies that the dilemma strength in PD significantly affects the direction the assortative coefficient takes during evolutionary processes in theco-evolution model..
59. Aya Hagishima, Jun Tanimoto, Koji Nagayama, Sho Meno, Aerodynamic parameters of regular arrays of rectangular blocks with various geometries, Boundary-Layer Meteorology, 10.1007/s10546-009-9403-5, 132, 2, 315-337, 2009, The aerodynamic effects of various configurations of an urban array were investigated in a wind-tunnel experiment. Three aerodynamic parameters characterising arrays - the drag coefficient (Cd), roughness length (zo) and displacement height (d) - are used for analysis. Cd is based on the direct measurement of the total surface shear using a floating element, and the other two parameters are estimated by logarithmic fitting of the measured wind profile and predetermined total drag force. The configurations of 63 arrays used for measurement were designed to estimate the effects of layout, wind direction and the height variability of the blocks on these parameters for various roughness packing densities. The results are summarised as follows: (1) The estimated Cd and zo of the staggered arrays peak against the plan area index (λp) and frontal area index (λf), in contrast with values for the square arrays, which are less sensitive to λp and λf. In addition, the square arrays with a wind direction of 45° have a considerably larger Cd, and the wind direction increases zo/H by up to a factor of 2. (2) The effect of the non-uniformity of roughness height on zo is more remarkable when λf exceeds 20%, and the discrepancy in zo is particularly remarkable and exceeds 200%. (3) The effect of the layout of tall blocks on Cd is stronger than that of short blocks. These results indicate that the effects of both wind direction and the non-uniformity of the heights of buildings on urban aerodynamic parameters vary greatly with λp and λf; hence, these effects should be taken into account by considering the roughness packing density..
60. Jun Tanimoto, Promotion of cooperation through co-evolution of networks and strategy in a 2 × 2 game, Physica A: Statistical Mechanics and its Applications, 10.1016/j.physa.2008.11.023, 388, 6, 953-960, 2009.03, A 2×2 game model implemented by co-evolution of both networks and strategies is established. An existing link between two agents is killed through network adaptation, which then establishes a new link to replace it. Strategy is defined as an offer of "cooperation" (C) or "defection" (D) by an agent. Both networks and strategies are synchronously renovated in each simulation time step. After killing the link with the most disadvantageous neighbor, we consider network adaptations that involve rewiring to (1) a randomly selected agent, (2) a proportionally selected agent (through a roulette selection process based on the degrees of respective agents), (3) an agent randomly selected among a set of neighbors of the neighbors, excluding the most disadvantageous neighbor. Several numerical experiments considering various 2×2 game classes, including Prisoner's Dilemma (PD), Chicken, Leader, and Hero, reveal that the proposed co-evolution mechanism can solve dilemmas in the PD game class. The result of solving a dilemma is the development of mutual-cooperation reciprocity (R reciprocity), which arises through the emergence of several cooperative hub agents, which have many links in a heterogeneous and assortative social network. However, the co-evolution mechanism seems counterproductive in the case of the Leader and Hero game classes, where alternating reciprocity (ST reciprocity) is more demanding. It is also suggested that the assortative and cluster coefficients of a network affect the emergence of cooperation for R reciprocity..
61. Atsuo Yamauchi, Jun Tanimoto, Aya Hagishima, Hiroki Sagara, Dilemma game structure observed in traffic flow at a 2-to-1 lane junction, Physical Review E - Statistical, Nonlinear, and Soft Matter Physics, 10.1103/PhysRevE.79.036104, 79, 3, 2009.03, Using a cellular automaton traffic model based on the stochastic optimal velocity model with appropriate assumptions for both incoming and outgoing vehicle boundaries, the so-called bottleneck issue on a lane-closing section was investigated in terms of game theory. In the system, two classified driver agents coexist: C agents (cooperative strategy) always driving in the first lane and D agents (defective strategy) trying to drive in a lower-density lane whether the first or the second lane. In high-density flow, D agents' interruption into the first lane from the second just before the lane-closing section creates a heavier traffic jam, which reduces social efficiency. This particular event can be described with a prisoner's dilemma game structure..
62. Jun Tanimoto, A simple scaling of the effectiveness of supporting mutual cooperation in donor-recipient games by various reciprocity mechanisms, BioSystems, 10.1016/j.biosystems.2008.11.004, 96, 1, 29-34, 2009.04, In donor-recipient games (DRG), one of the sub-classes of Prisoner's Dilemma (PD), it is well-known that a game structure is described by two parameters benefit (b) and cost (c) of cooperation. By means of a series of numerical experiments, we proved that the effectiveness of supporting mutual cooperation in DRG by various reciprocity mechanisms can be expressed in a single game structural parameter, b/c. This also implies that the dilemma strength in various donor-recipient games with various reciprocity mechanisms can be evaluated only by b/c, which is consistent with the previous novel finding by Nowak. It was also discussed whether this kind of parameterization idea can be extended to general games in PD game class..
63. Jun Tanimoto, Aya Hagishima, Takeshi Iwai, Yukiko Isayama, Total utility demand prediction considering variation of occupants' behavior schedules, Journal of Environmental Engineering (Japan), 10.3130/aije.74.579, 74, 639, 579-586, 2009.05, A holistic numerical model to predict total utility demand such as thermal requirement, various energies, domestic hot water, and city water of a residential house or a set of dwellings like a residential building, a residential area and even a city was established, which we call Total Utility Demand Prediction System (TUD-PS). The system based on the methodology for generating actual inhabitants' behavior schedules with 15 minutes time-resolution, previously reported, and a dynamic thermal load calculation. The latter part of the model takes account into the probabilistic model for HVAC turning On/ Off events derived from the Markov Chain, also previously developed, which can realize to obtain probabilistic thermal requirement impacted by inhabitants' On/ Off behaviors. Simulation concerned on seasonal and peak loads for a single dwelling reveals that the so-called maximum load is phenomenally influenced by the assumption whether HVAC turning On/ Off events are probabilistic or deterministic. Hence, a spatial accumulated time-series of utility demands of respective dwellings must be predicted by the proposed model, where simultaneous dynamics of respective dwellings can be reproduced, at least, must not be applied a conventional and practical method where you predict a holistic demand by superposition of a demand at a typical and ideal dwelling..
64. Jun Tanimoto, Aya Hagishima, Yasutaka Tanaka, A study on the bottleneck effect observed in an emergency evacuation exit employed by multi-agent simulation and mean-field approximation analysis, Journal of Environmental Engineering (Japan), 10.3130/aije.74.753, 74, 640, 753-757, 2009.06, An improved cellular automaton model based on Yanagjsawa & Tomoeda , Nishinari (2007) was established, where both Static Floor Field and collision effect were considered Several model parameters were carefully determined by going through a turning process based on experimental data provided by other previous studies. Both results by simulation based on the model and analytical approach derived from the so-called Mean-Field Approximation proved that the outflow rate from an evacuation exit, usually estimated by the so-called flow coefficient, can be improved by putting appropriate obstacles in front of the exit This is because the appropriate allocation of obstacles can deflate collision probability at the exit by increasing collisions around the obstacles before the exit..
65. J. T. Oliveira, Aya Hagishima, Jun Tanimoto, Estimation of passive cooling efficiency for environmental design in Brazil, Energy and Buildings, 10.1016/j.enbuild.2009.02.006, 41, 8, 809-813, 2009.08, An estimation of passive cooling techniques was conducted for 14 cities in Brazil, using a fairly accurate algorithm that accounts for heat conduction, convection, radiation, and evaporation; this was done to determine the amount of heat gain/loss of room air, defined as a particular quantitative index for passive techniques. Heat gains and losses were calculated for four envelope conditions - namely, insulated, high-albedo, wet surface, and a combination of the previous two - and compared to a case assumed to be the standard condition. A conclusion drawn was that a passive design is efficient in decreasing the need for cooling in typical dwellings in Brazil; solutions should differ with regional climate characteristics. In semi-arid areas, evaporative cooling showed the best results. Reduced heat gain was found during the warm seasons for all cities, along with increased heat gain during the cool seasons for mid-latitude cities. In particular, a combination of high-albedo enveloping and evaporation can greatly decrease heat gain in building walls. High-albedo surfaces in the sub-tropical areas found in southern Brazil are more efficient. It is suggested that passive techniques should be conceived in such a way so as to work during the cooling season and be disabled during mild ones..
66. Jun Tanimoto, Aya Hagishima, A stochastic model to predict off/on cooling schedule in dwellings applied by multilayered neural network, Journal of Environmental Engineering (Japan), 10.3130/aije.74.937, 74, 642, 937-942, 2009.08, In our previous study (Tanimoto & Hagishima (2005), Energy and Buildings 37), a set of state transition probabilities for the Markov Chain dealing with on/off cooling schedule in dwellings was proposed. Obtained probability of turning on an air conditioning system was defined in a form of Sigmoid-function by indoor globe temperature. Obviously, a real stochastic event of shifting from the off to on state cannot be affected by only indoor environmental parameters but also by other complex factors such as presence probability of family members, time, either weekday or holiday etc. In this paper, we report an alternative model based on the Multilayered Neural Network to predict off/on cooling schedule. We gathered field measurement data on familial dwellings during summer 2008 by deploying handy type hygrothermal meters with self-recording functions to measure room air, globe and blow-off air temperature of an air conditioner. The assumed Multilayered Neural Network has 9 nodes in both input and hidden layers, and 1 single node in output layer implying either state shifting from off toon (1) or not (0). The information given to the input layer nodes consists of what time, whether weekday of holiday, presence probability of inhabitants and PPD (Predicted Percentage of Dissatisfied). PPD derived from the theory of PMV is applied as a representative parameter for the indoor environment instead of globe temperature, since it contains various influences. The field measurement data sets were divided into two parts: teaching data and data for validation. The model trained by the teaching data was confirmed to reproduce state transition characteristic of the validation period, which seems complex and is determined by various inhabitants' manners. The model performance to reproduce is observed much excellent than the previous model derived from the Markov Chain..
67. Jun Tanimoto, Aya Hagishima, Total utility demand prediction system for dwellings based on stochastic processes of actual inhabitants, Journal of Building Performance Simulation, 10.1080/19401490903580767, 3, 2, 155-167, 2010.06, This article describes a new methodology to calculate the likely utility load profiles (energy such as power, natural gas, space heating and cooling, and other thermal requirements, as well as city water) in a dwelling. This calculation takes into account the behavioural variations of the dwelling inhabitants. The proposed method contains a procedure for cooling load calculations based on a series of Monte Carlo simulations where the heating, ventilating and air conditioning (HVAC) on/off state and the indoor heat generation schedules are varied, time-step by timestep. A data set of time-varying inhabitant behaviour schedules, with a 15-min resolution, generated by the authors in previous studies and validated by a comparison analysis to several field measurement data sets, was integrated into the model. The established model, which is called the total utility demand prediction system, can be applied to, for example, likely estimation of an integrated space maximum requirement, such as the total load of a building or an urban area. In a series of numerical experiments, huge discrepancies were found between the conventional results and those considering the time-varying inhabitant behaviour schedules. In particular, deriving the dynamic state change, of having the HVAC on/off from the inhabitants' schedules, was found to be a significant factor in the maximum cooling and heating loads..
68. Jun Tanimoto, Atsuo Yamauchi, Does "game participation cost" affect the advantage of heterogeneous networks for evolving cooperation?, Physica A: Statistical Mechanics and its Applications, 10.1016/j.physa.2010.01.033, 389, 11, 2284-2289, 2010.06, Masuda [N. Masuda, Participation costs dismiss the advantage of heterogeneous networks in evolution of cooperation, Proceedings of the Royal Society B 274 (2007) 1815-1821] reported that a game participation cost (expressed by adding same negative values to all four elements in a 2 × 2 payoff matrix) affects the advantage of heterogeneous networks in the evolution of cooperation. We show that this finding is not always true depending on the features of the network, indicating that participation costs help cooperation in certain situations rather than destroy it. In a weaker dilemma game on a scale free network derived from the Barabasi & Albert algorithm with a larger average degree, game participation cost helps rather than destroy the network reciprocity..
69. Jun Tanimoto, The effect of assortativity by degree on emerging cooperation in a 2 × 2 dilemma game played on an evolutionary network, Physica A: Statistical Mechanics and its Applications, 10.1016/j.physa.2010.03.020, 389, 16, 3325-3335, 2010.08, A series of numerical experiments on 2×2 games using a co-evolutionary model, including both networks and strategies, was performed. A relationship between assortativity by degree of the evolved network and emerging cooperation was investigated. In the Prisoner's Dilemma (PD) game class, the evolutionary trajectory for a weak dilemma game favors a network with positive assortative coefficient and easily attains a cooperative situation. A game implemented with a stronger dilemma, however, makes the network very heterogeneous, with a negative assortative coefficient required to solve the dilemma situation. This implies that the dilemma strength in the PD significantly affects the direction adopted by the assortative coefficient during evolutionary processes in the co-evolutionary model..
70. Aya Hagishima, Ken Ichi Narita, Jun Tanimoto, Investigation on turbulent characteristics within urban canopy layer based on outdoor experiment using fine wire thermocouples, Journal of Environmental Engineering (Japan), 10.3130/aije.75.877, 75, 656, 877-883, 2010.10, The authors performed a field measurement on the turbulent characteristics of an urban canopy layer over a cubical array using numerous fine thermocouples and nine ultra sonic anemometers. The time and spatially fluctuations of air temperature were discussed comparing the instantaneous velocity under the unstable condition. The result clearly showed that the passage of the microffont of temperature above the canopy, which are correlate the sweep and ejection motions due to a turbulent organized structure (TPS) developed within an inertial sublayer, in contrast, the temperature fluctuation below the canopy height is less sensitive to the TOB..
71. Atsuo Yamauchi, Jun Tanimoto, Aya Hagishima, What controls network reciprocity in the Prisoner's Dilemma game?, BioSystems, 10.1016/j.biosystems.2010.07.017, 102, 2-3, 82-87, 2010.11, The evolutionary Prisoner's Dilemma game in structured networks has been studied extensively to understand network reciprocity. However, in some cases results of these studies cannot be compared because not only the network structures but also the network parameters, rules for updating strategies, and update dynamics differ among them. In this study, we investigated the effect of experimental conditions by conducting a series of systematic factorial experiments. We found that those experimental assumptions are significantly important in network reciprocity, although we confirmed that network reciprocity can be basically explained by the average degree of the network (Nowak, 2006; Ohtsuki et al., 2006)..
72. Jun Tanimoto, Aya Hagishima, Yasukaka Tanaka, Study of bottleneck effect at an emergency evacuation exit using cellular automata model, mean field approximation analysis, and game theory, Physica A: Statistical Mechanics and its Applications, 10.1016/j.physa.2010.08.032, 389, 24, 5611-5618, 2010.12, An improved cellular automaton model for pedestrian dynamics was established, where both static floor field and collision effect derived from game theory were considered. Several model parameters were carefully determined by previous studies. Results obtained through model-based simulation and analytical approach (derived from mean field approximation) proved that outflow rate from an evacuation exit, which is usually estimated using outflow coefficient in building codes in Japan, can be improved by placing an appropriate obstacle in front of the exit. This can reduce collision probability at the exit by increasing collisions around the obstacles ahead of the exit..
73. Makoto Nakata, Atsuo Yamauchi, Jun Tanimoto, Aya Hagishima, Dilemma game structure hidden in traffic flow at a bottleneck due to a 2 into 1 lane junction, Physica A: Statistical Mechanics and its Applications, 10.1016/j.physa.2010.08.005, 389, 23, 5353-5361, 2010.12, Following Yamauchi's study [A. Yamauchi, J. Tanimoto, A. Hagishima, H. Sagara, Dilemma game structure observed in traffic flow at a 2-to-1 lane junction, Physical Review E 79 (2009) 036104], we find that several social dilemma structures are represented by n-person Prisoner's Dilemma (n-PD) games in certain traffic flow phases at a bottleneck caused by a lane-closing section. In this study, the stochastic NishinariFukuiSchadschneider (S-NFS) model was adopted as a cellular automaton traffic model. In the system, two classes of driver-agents coexist: C-Agents (cooperative strategy) always driving in the first lane, and D-Agents (defective strategy) trying to drive in a lower-density lane, whether the first or the second lane. In relatively high-density flow phases, such as the metastable phase and the high-density phase, we found n-PD games, where D-Agents' interruption into the first lane from the second just before the lane-closing section creates a heavier traffic jam, which reduces social efficiency. This could be solved by decreasing the interruption probability, which can be realized by a provision where drivers in the first lane firmly refuse interruptions..
74. Jun Tanimoto, Aya Hagishima, Takeshi Iwai, Naoki Ikegaya, Total utility demand prediction for multi-dwelling sites considering variation of occupant behavior schedules, 12th Conference of International Building Performance Simulation Association Building Simulation 2011, BS 2011 Proceedings of Building Simulation 2011: 12th Conference of International Building Performance Simulation Association, 2011, Based on the authors' previous works, this paper describes a new methodology that uses a bottom-up approach for accurately calculating the time series utility loads (e.g., energy, power, city water, hot water, etc.) for multi-dwelling systems, including residential buildings, residential block areas, and even the entire city. This calculation considers the behavioral variations of the inhabitants of the dwellings. The proposed method constitutes a procedure for calculating cooling/ heating loads based on a series of Monte Carlo simulations where the HVAC on/off state and the indoor heat generation schedules are varied at a time interval. A data set of time-varying inhabitant behavior schedules with a 15-minute time resolution was integrated into the model. The established model, which is called the Total Utility Demand Prediction System (TUD-PS), was integrated to estimate a multi-dwelling system, where we can accurately predict various peak demands and seasonal or annual demands. By applying this method to a typical residential building, we highlighted several advantages of TUD-PS..
75. Jun Tanimoto, Aya Hagishima, Total utility demand prediction considering variation of occupants' behavior schedules applied to multi dwellings, Journal of Environmental Engineering (Japan), 10.3130/aije.76.141, 76, 660, 141-149, 2011, Following the authors' previous work, this paper describes a new methodology in calculating accurately the time series utility loads (energy, power, citywater, hot water, etc.) for multi-dwelling system such as a whole residential building, residential block area, even a city by means of the so-called bottom-up approach. This calculation takes into account the behavioral variations of the dwelling inhabitants. The proposed method contains a procedure for procedure for cooling load calculations based on a series of Monte Carlo simulations where the HVAC on/off state and the indoor heat generation schedules are varied, time-step by time-step. A data set of time-varying inhabitant behavior schedules, with a 15 minute resolution, was integrated into the model. The established model, which is called the Total Utility Demand Prediction System (TUD-PS) was integrated to estimate multi dwellings system, where we can accurately argue various peak demands and seasonal or annual demands. By applying to a typical residential bmlding, we highlight several advantages of TUD-PS..
76. Sheikh Ahmad Zaki, Aya Hagishima, Jun Tanimoto, Spatial distribution of pressure drag acting on rectangular block arrays with various layouts, 12th Conference of International Building Performance Simulation Association Building Simulation 2011, BS 2011 Proceedings of Building Simulation 2011: 12th Conference of International Building Performance Simulation Association, 1686-1693, 2011, This study reported a series of wind tunnel experiments on the spatial distribution of the pressure drag acting on the walls of rectangular block arrays, which were arranged in staggered, square, and diamond layouts under the conditions of different packing densities. The obtained bulk pressure coefficients of a block located in various staggered arrays showed clear dependency of packing density. This result suggests the importance of the consideration for the reduction of wind-driven cross ventilation due to neighborhood densely built-up area in building simulation coupled with ventilation model..
77. Junji Ohama, Aya Hagishima, Jun Tanimoto, Research on social value measurement of global warming and heat island countermeasures applied conjoint analysis, Journal of Environmental Engineering (Japan), 10.3130/aije.76.211, 76, 660, 211-219, 2011, A systematical field survey applied Conjoint Analysis (CA) concerned on two specified social issues; global warming and heat island problems is conducted. We applied the so-called web-site survey to secure both quantity and quality of a series of acquired data sets. Both obtained Marginal Willing to Pay (MWTP) for the global warming and heat island issues seems plausible. Interestingly, it is observed an evident tendency that younger subjects incline to pay more than older subjects, which implies younger people paying much attention to the environmental issues. We found that the level range of payment in a questionnaire significantly affects MWTP, which means how design a payment range would bring considerable bias in some cases. Also a principle problem whether a subject's payment was questioned by explicit as a form of additional payment to the public or implicit as a form of re-allocation of already-collected tax from the people, is observed significantly influential in the MWTP The result also suggests that three-choice type CA seems better than pairwise type CA to obtain plausible MWTP when a questionnaire relates to a certain ideal issue that is difficult for subjects to understand its trade-off structure in proper way..
78. Jun Tanimoto, Influence of strategy adaptation speed on network reciprocity for evolutionary prisoner's dilemma games, Sociobiology, 58, 2, 315-326, 2011, Following our previous study (Tanimoto, submitted to Physica A) on how network reciprocity is affected when strategy adaptation speed is slower than gaming speed, we conducted a series of simulations to obtain a deeper insight. In the case of a spatial prisoner s dilemma on a scale-free network with a spatial distribution of the strategy updating time scale, we found that a negative correlation between degree and strategy updating speed brings an extremely large cooperation-enhancing effect. This might be because a cooperative hub agent who is insensitive to strategy adaptation can protect against defection invasion at the initial stage of a simulation episode to initiate a cooperative situation..
79. Naoki Ikegaya, Aya Hagishima, Jun Tanimoto, Yu Dai Tanaka, Ken Ichi Narita, Effects on bulk scalar coefficient of wind angle, Development of scalar boundary layer and flow field near roughness, Journal of Environmental Engineering (Japan), 10.3130/aije.76.67, 76, 659, 67-73, 2011, The authors performed wind-tunnel experiments to investigate bulk scalar coefficients between an urban-like 3 dimensional roughnesses and atmosphere using salinity method. In this paper, three main effects were investigated. Firstly, the effects of randomness of layouts of each block were discussed. Bulk scalar coefficients were measured on arrays with cubic blocks, whose angle against the wind were randomly changed. Secondly the sizes of scalar source were considered under three conditions of plan area indices with square and staggered array. The results showed that bulk scalar coefficients were affected by the size as mentioned in previous studies, however, the relation between geometrical conditions and the coefficients were independent with the size. Lastly, the effects of vertical mixture of air caused by roughness elements were discussed based on the measurement of wind profile for each array. This investigation showed that certain plan layouts might strongly affect on vertical exchange of air..
80. Sheikh Ahmad Zaki, Aya Hagishima, Jun Tanimoto, Naoki Ikegaya, Aerodynamic Parameters of Urban Building Arrays with Random Geometries, Boundary-Layer Meteorology, 10.1007/s10546-010-9551-7, 138, 1, 99-120, 2011, It is difficult to describe the flow characteristics within and above urban canopies using only geometrical parameters such as plan area index (λp) and frontal area index (λf) because urban surfaces comprise buildings with random layouts, shapes, and heights. Furthermore, two types of 'randomness' are associated with the geometry of building arrays: the randomness of element heights (vertical) and that of the rotation angles of each block (horizontal). In this study, wind-tunnel experiments were conducted on seven types of urban building arrays with various roughness packing densities to measure the bulk drag coefficient (Cd) and mean wind profile; aerodynamic parameters such as roughness length (zo) and displacement height (d) were also estimated. The results are compared with previous results from regular arrays having neither 'vertical' nor 'horizontal' randomness. In vertical random arrays, the plot of Cd and zo versus λf exhibited a monotonic increase, and zo increased by a factor of almost two for λf = 48-70%. Cd was strongly influenced by the standard deviation of the height of blocks (σ) when λp ≥ 17%, whereas Cd was independent of σ when λp = 7%. In the case of horizontal random arrays, the plot of the estimated Cd against λf showed a peak. The effect of both vertical and horizontal randomness of the layout on aerodynamic parameters can be explained by the structure of the vortices around the blocks; the aspect ratio of the block is an appropriate index for the estimation of such features..
81. Motoya Wakiyama, Jun Tanimoto, Reciprocity phase in various 2×2 games by agents equipped with two-memory length strategy encouraged by grouping for interaction and adaptation, BioSystems, 10.1016/j.biosystems.2010.10.009, 103, 1, 93-104, 2011.01, This paper numerically investigates 2 × 2 games involving the Prisoner's Dilemma, Chicken, Hero, Leader, Stag Hunt, and Trivial Games in which agents have a strategy expressed by five-bit, two-memory length. Our motivation is to explore how grouping for game interaction and strategy adaptation influence ST reciprocity and R reciprocity (Tanimoto and Sagara, 2007a [Tanimoto, J., Sagara, H., 2007a. A study on emergence of coordinated alternating reciprocity in a 2 × 2 game with 2-memory length strategy. Biosystems 90(3), 728-737]. Enhanced R reciprocity is observed with the stronger grouping for game interaction when a relatively stronger grouping for strategy adaptation is assumed. On the other hand, enhanced ST reciprocity emerged with the stronger grouping for strategy adaptation when the relatively weaker grouping for game interaction is imposed. Our numerical experiment deals with those two groupings independently and dependently..
82. Atsuo Yamauchi, Jun Tanimoto, Aya Hagishima, An analysis of network reciprocity in Prisoner's Dilemma games using Full Factorial Designs of Experiment, BioSystems, 10.1016/j.biosystems.2010.10.006, 103, 1, 85-92, 2011.01, Despite hundreds of studies on the Prisoner's Dilemma (PD) game, understanding about network reciprocity remains a unsolved puzzle. Thus, we performed a series of Full Factorial Design of Experiments (FFDOE) to evaluate what dominates emerging cooperation in the PD game on various networks. The results qualitatively reveal the influence of each factor and show that some combinations of factors have complicated interactions. Remarkably, the choice of strategy update rule or update dynamics is much more important than the type of network imposed or, at least, the factorial effect of the average degree of the network reported by Nowak (Science 314, 5805, 1560-1563, 2006) and Ohtsuki et al. (Nature 441, 502-505, 2006). Furthermore, the decision of which PD game type to investigate (whether all PD games, PD-Chicken boundary games or Donor & Recipient games) is important for discussing network reciprocity..
83. Satoshi Kokubo, Jun Tanimoto, Aya Hagishima, A new Cellular Automata Model including a decelerating damping effect to reproduce Kerner's three-phase theory, Physica A: Statistical Mechanics and its Applications, 10.1016/j.physa.2010.10.027, 390, 4, 561-568, 2011.02, Most of the conventional traffic Cellular Automaton (CA) models based on the NagelSchreckenberg model (NaSch model) have two problems: an unrealistic deceleration dynamics when a vehicle agent collides with a preceding vehicle in a stopping event, and the problem with reproducing the synchronized flow in Kerner's three-phase theory. In this paper, a revised stochastic NishinariFukuiSchadschneider (S-NFS) model, belonging to the class of NaSch models, is presented. The proposed CA model, where a random braking effect is improved by considering the dependency on the velocity difference and heading distance with a preceding vehicle, is confirmed to overcome the two above-mentioned drawbacks..
84. Shinji Kukida, Jun Tanimoto, Aya Hagishima, Analysis of the influence of lane changing on traffic-flow dynamics based on the cellular automaton model, International Journal of Modern Physics C, 10.1142/S012918311101621X, 22, 3, 271-281, 2011.03, Many cellular automaton models (CA models) have been applied to analyze traffic flow. When analyzing multilane traffic flow, it is important how we define lane-changing rules. However, conventional models have used simple lane-changing rules that are dependent only on the distance from neighboring vehicles. We propose a new lane-changing rule considering velocity differences with neighboring vehicles; in addition, we embed the rules into a variant of the NagelSchreckenberg (NaSch) model, called the S-NFS model, by considering an open boundary condition. Using numerical simulations, we clarify the basic characteristics resulting from different assumptions with respect to lane changing..
85. Jun Tanimoto, A study of a quadruple co-evolutionary model and its reciprocity phase for various Prisoner's Dilemma game, International Journal of Modern Physics C, 10.1142/S0129183111016324, 22, 4, 401-417, 2011.04, We present and numerically investigate a quadruple co-evolutionary model for 2 × 2 Prisoner's Dilemma games which allows not only for agents to adopt strategy (Cooperation C or Defection D) and for network topology, but also for the probability of link rewiring that controls the speed of network evolution and the updating rule itself. The results of a series of simulations reveal that C agents in a coexisting phase increase their rewiring probability to avoid neighboring D agents' exploitation through the Game Exit Option. This evolutionary process leads most agents to adopt pairwise updating even though Imitation Max update adopted by all agents brings a higher payoff..
86. Aya Hagishima, Jun Tanimoto, Manato Yamaguchi, Yoshiki Kikuchi, Wind tunnel experiment on effect of shape of an obstacle on total drag force of regular array, Journal of Environmental Engineering (Japan), 10.3130/aije.76.485, 76, 663, 485-492, 2011.05, Drag coefficients (Cd) and vertical wind profiles for regular arrays were measured in a systematic series of wind tunnel experiment to investigate Hie shape effect of roughness element on Cd and air flow dynamics, and following results were presented. 1) Cd of an array consists of miniature vehicles was compared with that of an array consists of a combination of two different blocks, and the former is 10% to 20% lower than the latter due to the effect of the curved surface, in spite of their similar external scale. 2) The staggered array consists of elements with higher ratio shows larger peak of Cd against roughness density because of the less bluff-body character of a slender obstacle. 3) Turbulent characteristics within canopy layer of an array with high aspect ratio is similar to that of plant canopy..
87. Yuichi Tabata, Akashi Mochida, Naoko Konno, Aya Kikuchi, Takashi Maruyama, Aya Hagishima, Jun Tanimoto, Optimization of model coefficients for different configurations and densities of car molds
Development of CFD model for reproducing aerodynamic effects of moving automobiles (Part 1), Journal of Environmental Engineering (Japan), 10.3130/aije.76.831, 76, 667, 831-837, 2011.09, The aim of this study is to develop a simulation method for predicting the wind environment and turbulent diffusion process, whichare affected by moving automobiles within the real situation of urban street canyon. In this study, a simulation method to reproduce the aerodynamic effects generated from the moving automobiles based on the methodology of canopy models, namely 'Vehicle Canopy Model', was developed. Furthermore, a series of wind tunnel measurements of flow over car-shaped roughness elements and the dragforces caused by the roughness with different configurations and densities were carried out. By comparing the results of CFD predictions of the developed 'Vehicle Canopy Model' with experimental data, the accuracy of the developed model was examined..
88. Keizo Shigaki, Jun Tanimoto, Aya Hagishima, A revised stochastic optimal velocity model considering the velocity gap with a preceding vehicle, International Journal of Modern Physics C, 10.1142/S0129183111016749, 22, 9, 1005-1014, 2011.09, The stochastic optimal velocity (SOV) model, which is a cellular automata model, has been widely used because of its good reproducibility of the fundamental diagram, despite its simplicity. However, it has a drawback: in SOV, a vehicle that is temporarily stopped takes a long time to restart. This study proposes a revised SOV model that suppresses this particular defect; the basic concept of this model is derived from the car-following model, which considers the velocity gap between a particular vehicle and the preceding vehicle. A series of simulations identifies the model parameters and clarifies that the proposed model can reproduce the three traffic phases: free, jam, and even synchronized phases, which cannot be achieved by the conventional SOV model..
89. Jun Tanimoto, Hiroki Sagara, Social diffusive impact analysis based on evolutionary computations for a novel car navigation system sharing individual information in urban traffic systems, Journal of Navigation, 10.1017/S037346331100021X, 64, 4, 711-725, 2011.10, In this study, an experiment to establish a model for human-environment social systems, a multi-agent simulation model to deal with urban traffic congestion problems involving automobiles embedded with several strategies of car navigation systems (CNS), is presented. A shortest time route with route information sharing strategy (ST-RIS) is believed to be one of the solutions for a novel CNS based on bilateral information shared among automobile agents. We assume several strategies including ST-RIS for agents, which are defined differently in terms of their information-handling process. The question of which strategy is most appropriate for solving urban traffic congestion can be seen as a social dilemma, because social holistic utility may conflict with an agent's individual utility. The presented model shows that this social dilemma can be observed as a typical chicken-type dilemma, or as a typical minority game, where an agent who has adopted a minority strategy can earn more utility compared to when other strategies are used. Consequently, the model has illustrated that shortest time route with partial route information sharing strategy (ST-pRIS), which is an advanced strategic form of ST-RIS in which only partial information is shared among agents, has moderate potential to be diffused in a society from the viewpoint of the evolutionary game theory..
90. Naoki Ikegaya, Aya Hagishimaand, Jun Tanimoto, Large-eddy simulation large-eddysimulation onscalartransferphenomena betweenurbansurfaceandatmosphere, Journal of Environmental Engineering (Japan), 10.3130/aije.76.943, 76, 668, 943-951, 2011.10, The authors performed a numerical simulation of scalar transfer phenomena between an urban surface and atmosphere. A parallelized large-eddy simulation model was adopted for the simulation. Two types of regular block arrays, a square array and staggered array, were arranged on the floor of computational domains. It was assumed that area scalar source was installed on the floor of arrays and scalar fluxes were estimated by using a wall function based on a logarithmic law. The results are summarized as follows. (l) The flow statistics of the normalized wind speed and turbulence intensity above a canopy showed good agreement with that obtained experimentally. (2) Scalar profiles shows self-similarity after 3rd rows. (3) Scalar boundary layer develops rapidly especially the edge of the scalar source area because of upward wind due to roughness..
91. Noriyuki Kishimoto, Satoshi Kokubo, Jun Tanimoto, Network reciprocity on spatial prisoner's dilemma games by Continuous-binary strategy, 2012 Joint 6th International Conference on Soft Computing and Intelligent Systems, SCIS 2012 and 13th International Symposium on Advanced Intelligence Systems, ISIS 2012 6th International Conference on Soft Computing and Intelligent Systems, and 13th International Symposium on Advanced Intelligence Systems, SCIS/ISIS 2012, 10.1109/SCIS-ISIS.2012.6505166, 663-668, 2012, For 2 × 2 games, especially the Spatial Prisoner's Dilemma (SPD), most of the previous studies presumed that players can offer either cooperation (C) or defection (D), the so-called discrete strategy. In this paper, we define Continuous-binary strategy instead of discrete strategy. And a systematic series of numerical simulations reports that it enhances the network reciprocity for SPD. This new strategy is based on our previous finding that continuous and mixed strategy are robust in boundary games of Chicken and PD (BCH), and Stag Hunt and PD (BSH), respectively. The new strategy allows to put both advantages of continuous and mixed strategies on usual discrete strategy together in one model..
92. Jun Tanimoto, Aya Hagishima, Takeshi Iwai, Naoki Ikegaya, Total utility demand prediction for multi-dwelling sites by a bottom-up approach considering variations of inhabitants' behaviour schedules, Journal of Building Performance Simulation, 10.1080/19401493.2012.680498, 6, 1, 53-64, 2012.01, This article reports systematic case studies based on a Total Utility Demand Prediction System presented in the authors' previous works, in which one can follow a bottom-up approach to accurately calculate the time series utility loads (energy, power, city water, hot water, etc.) for multi-dwelling systems, including residential buildings, residential block areas and even an entire city. This calculation considers the behavioural variations of the inhabitants of the dwellings. In the case studies, we assumed a residential building consisting of 100 independent dwellings to accurately predict various peak demands and seasonal or annual demands. A series of simulations reveals that considering time-varying inhabitant behaviour schedules significantly affects the peak loads. Hence, HVAC COP, inhabitants' age and their family type significantly influence the peak loads and their accurate time-series..
93. Jun Tanimoto, Aya Hagishima, State transition stochastic model for predicting off to on cooling schedule in dwellings as implemented using a multilayered artificial neural network, Journal of Building Performance Simulation, 10.1080/19401493.2010.533388, 5, 1, 45-53, 2012.01, Our previous study (Tanimoto, J. and Hagishima, A. 2005. State transition probability for the Markov model dealing with on/off cooling schedule in dwellings. Energy and Buildings, 37, 181-187) proposed a set of state transition probabilities for the Markov chain dealing with the on/off cooling schedule in dwellings. The probability of turning on an air conditioner was defined in the form of a sigmoid function by the indoor globe temperature. Obviously, a real stochastic event of shifting from the off to on state is affected by not only indoor thermal quality parameters but also by other complex factors, such as the presence of family members, time of the day and whether it is a weekday or holiday. In this article, we report an alternate model, based on a multilayered artificial neural network (MANN), for predicting the off to on cooling schedule. We gathered field measurement data on family dwellings during the summer of 2008 by deploying hygrothermometers with recording functions to measure the room temperature and the globe and blowout air temperature of the air conditioner. The MANN used has nine nodes in both its input and hidden layers and a single node in its output layer, which implies that the state is either shifting from off to on (1) or not (0). The information provided to the input layer nodes includes the time of the day, whether it is a weekday or holiday, the probability of the presence of inhabitants and the predicted percentage of dissatisfied (PPD) people. PPD, derived from PMV theory, is applied as a representative parameter of the indoor thermal quality, in place of the globe temperature, since it accounts for various influences. The field measurement datasets were divided into two parts: teaching data and data for validation. A model trained by the teaching data was confirmed to reproduce the state transition characteristic of the validation period, which seems complex and is determined by the behaviour of various inhabitants. The performance of the model in reproducing this behaviour is improved over that of the previous model derived from the Markov chain..
94. Jun Tanimoto, Makoto Nakata, Aya Hagishima, Naoki Ikegaya, Spatially correlated heterogeneous aspirations to enhance network reciprocity, Physica A: Statistical Mechanics and its Applications, 10.1016/j.physa.2011.08.039, 391, 3, 680-685, 2012.02, Perc & Wang demonstrated that aspiring to be the fittest under conditions of pairwise strategy updating enhances network reciprocity in structured populations playing 2×2 Prisoner's Dilemma games (Z. Wang, M. Perc, Aspiring to the fittest and promoted of cooperation in the Prisoner's Dilemma game, Physical Review E 82 (2010) 021115; M. Perc, Z. Wang, Heterogeneous aspiration promotes cooperation in the Prisoner's Dilemma game, PLOS one 5 (12) (2010) e15117). Through numerical simulations, this paper shows that network reciprocity is even greater if heterogeneous aspirations are imposed. We also suggest why heterogeneous aspiration fosters network reciprocity. It distributes strategy updating speed among agents in a manner that fortifies the initially allocated cooperators' clusters against invasion. This finding prompted us to further enhance the usual heterogeneous aspiration cases for heterogeneous network topologies. We find that a negative correlation between degree and aspiration level does extend cooperation among heterogeneously structured agents..
95. Weicai Zhong, Satoshi Kokubo, Jun Tanimoto, How is the equilibrium of continuous strategy game different from that of discrete strategy game?, BioSystems, 10.1016/j.biosystems.2011.10.001, 107, 2, 88-94, 2012.02, Cooperation in the prisoner's dilemma (PD) played on various networks has been explained by so-called network reciprocity. Most of the previous studies presumed that players can offer either cooperation (C) or defection (D). This discrete strategy seems unrealistic in the real world, since actual provisions might not be discrete, but rather continuous. This paper studies the differences between continuous and discrete strategies in two aspects under the condition that the payoff function of the former is a linear interpolation of the payoff matrix of the latter. The first part of this paper proves theoretically that for two-player games, continuous and discrete strategies have different equilibria and game dynamics in a well-mixed but finite population. The second part, conducting a series of numerical experiments, reveals that such differences become considerably large in the case of PD games on networks. Furthermore, it shows, using the Wilcoxon sign-rank test, that continuous and discrete strategy games are statistically significantly different in terms of equilibria. Intensive discussion by comparing these two kinds of games elucidates that describing a strategy as a real number blunts D strategy invasion to C clusters on a network in the early stage of evolution. Thus, network reciprocity is enhanced by the continuous strategy..
96. Jun Tanimoto, Markus Brede, Atsuo Yamauchi, Network reciprocity by coexisting learning and teaching strategies, Physical Review E - Statistical, Nonlinear, and Soft Matter Physics, 10.1103/PhysRevE.85.032101, 85, 3, 2012.03, We propose a network reciprocity model in which an agent probabilistically adopts learning or teaching strategies. In the learning adaptation mechanism, an agent may copy a neighbor's strategy through Fermi pairwise comparison. The teaching adaptation mechanism involves an agent imposing its strategy on a neighbor. Our simulations reveal that the reciprocity is significantly affected by the frequency with which learning and teaching agents coexist in a network and by the structure of the network itself..
97. Sheikh Ahmad Zaki, Aya Hagishima, Jun Tanimoto, Experimental study of wind-induced ventilation in urban building of cube arrays with various layouts, Journal of Industrial Aerodynamics, 10.1016/j.jweia.2012.02.008, 103, 31-40, 2012.04, Urban airflow and dispersion processes have become matters of great concern from the viewpoints of urban heat island phenomena, thermal comfort of pedestrians, hazard control for toxic gases, wind-induced ventilation of urban buildings, and so on. In this study, the authors measured the spatial distribution of the pressure drag acting on the walls of rectangular block arrays in a wind tunnel. The arrays were arranged with staggered, square, and diamond layouts under different conditions of roughness and packing density. The total drag and wind profiles of the arrays were preliminarily measured. On the basis of experimental results, the contribution of pressure drag to the total surface drag on staggered cube arrays was estimated at greater than 95%. In addition, the bulk pressure coefficients C p for the arrays defined by mean velocity at a height of H, 2H and 20H were derived (H refers to the height of a block), and the clear relation between C p and the block packing densities were shown for rough estimation of wind-induced ventilation in urban buildings. In addition, the authors present a simple mathematical expression to explain the relationship..
98. Naoki Ikegaya, Aya Hagishima, Jun Tanimoto, Yudai Tanaka, Ken Ichi Narita, Sheikh Ahmad Zaki, Geometric Dependence of the Scalar Transfer Efficiency over Rough Surfaces, Boundary-Layer Meteorology, 10.1007/s10546-012-9698-5, 143, 2, 357-377, 2012.05, We performed a series of wind-tunnel experiments under neutral conditions in order to create a comprehensive database of scalar transfer coefficients for street surfaces using regular block arrays representing an urban environment. The objective is to clarify the geometric dependence of scalar transfer phenomena on rough surfaces. In addition, the datasets we have obtained are necessary to improve the modelling of scalar transfer used for computational simulations of urban environments; further, we can validate the results obtained by numerical simulations. We estimated the scalar transfer coefficients using the salinity method. The various configurations of the block arrays were designed to be similar to those used in a previous experiment to determine the total drag force acting on arrays. Our results are summarized as follows: first, the results for cubical arrays showed that the transfer coefficients for staggered and square layouts varied with the roughness packing density. The results for the staggered layout showed the possibility that the mixing effect of air can be enhanced for the mid-range values of the packing density. Secondly, the transfer coefficients for arrays with blocks of non-uniform heights were smaller than those for arrays with blocks of uniform height under conditions of low packing density; however, as the packing density increased, the opposite tendency was observed. Thirdly, the randomness of rotation angles of the blocks in the array led to increasing values of the transfer coefficients under sparse packing density conditions when compared with those for cubical arrays..
99. K. Shigaki, S. Kokubo, Jun Tanimoto, Aya Hagishima, Naoki Ikegaya, Does copy-resistance enhance cooperation in spatial prisoner's dilemma?, Europhysics Letters, 10.1209/0295-5075/98/40008, 98, 4, 2012.05, We propose a novel idea for the so-called pairwise-Fermi process by considering copy-resistance when an agent copies a neighbor's strategy, which implies that the focal agent with relatively affluent payoff vis-à-vis social average might be negative to copy her neighbor's strategy even if her payoff is less than the neighbor's payoff. Simulation results reveal that this idea with a revised strategy adaptation process significantly enhances cooperation for prisoner's dilemma games played on time-constant networks..
100. Aya Hagishima, Minsun Park, Jun Tanimoto, Questionnaire survey on preference of environmental factors of residential buildings, Journal of Environmental Engineering (Japan), 10.3130/aije.77.523, 77, 676, 523-531, 2012.06, This paper reported a questionnaire survey on consumers' preference for several attributes of a condominium unit carried out in Kanagawa, Japan. The questionnaire were designed based on paired comparison conjoint theory, analytical hierarchy process (AHP), and rank method to quantify the preference for floor area. specifications of low C02 emission and VOC emission, and information technology (IT) facility. The responses of stated preference on paired comparison were analyzed based on both multi-logit and multi-probit methods. The result suggests the effectiveness of an inter-comparison among several types of probability model for evaluating the estimated willingness to pay for a group of small sample size..
101. Keizo Shigaki, Jun Tanimoto, Zhen Wang, Satoshi Kokubo, Aya Hagishima, Naoki Ikegaya, Referring to the social performance promotes cooperation in spatial prisoner's dilemma games, Physical Review E - Statistical, Nonlinear, and Soft Matter Physics, 10.1103/PhysRevE.86.031141, 86, 3, 2012.09, We propose a new pairwise Fermi updating rule by considering a social average payoff when an agent copies a neighbor's strategy. In the update rule, a focal agent compares her payoff with the social average payoff of the same strategy that her pairwise opponent has. This concept might be justified by the fact that people reference global and, somehow, statistical information, not local information when imitating social behaviors. We presume several possible ways for the social average. Simulation results prove that the social average of some limited agents realizes more significant cooperation than that of the entire population..
102. Minsun Park, Aya Hagishima, Jun Tanimoto, Ken ichi Narita, Effect of urban vegetation on outdoor thermal environment
Field measurement at a scale model site, Building and Environment, 10.1016/j.buildenv.2012.02.015, 56, 38-46, 2012.10, The goal of this research is to bridge the gap between numerical studies and field measurements on thermal environment of a real urban street and to present information on the effects of urban vegetation suitable for use by designers and planners. Outdoor measurements were conducted at a scale model site consisting of an array of concrete cubes each 1.5 m high. Eight urban street units with various vegetation conditions were reproduced to examine the quantitative effects of vegetation along the sidewalk and in median strips on the thermal environment in summer. The results can be summarized as follows. The presence of four sidewalk trees reduces the wind speed inside the canopy by up to 51%. Trees along the sidewalk also decrease the globe temperature; the reduction is attributed mainly to the decrease in radiation flux resulting from the shade they cast. Moreover, thermal mitigation due to vegetation persists even when an area is shaded. In contrast, the mitigating effect of a vegetated median strip is not remarkable. A sidewalk facing a southwestern wall exhibited the most significant thermal mitigation..
103. Naoki Ikegaya, Aya Hagishima, Jun Tanimoto, Yu Dai Tanaka, A study on the similarity of the momentum and scalar roughness lengths over urban-like roughness, Journal of Environmental Engineering (Japan), 10.3130/aije.77.917, 77, 681, 917-923, 2012.11, We have performed a series of wind-tunnel experiments to measure scalar concentration profiles over urban-like roughness arrays. The concentration measurements revealed two features of scalar distribution. First, the high concentration filed was observed in the leeward region of each roughness element. Secondly, the averaged concentration became high up to the roughness height due to the updraft along the element and the boundary layer thickness drastically reach to the height in spite of the short length of scalar source area. In addition to the concentration measurements, we determined the roughness length of scalar based on the preliminary performed comprehensive study on scalar transfer coefficients, momentum transfer coefficients and wind profiles and discussed the similarity between momentum and scalar transfer phenomena by applying the relation between the Dalton number and the roughness Reynolds number..
104. Aya Hagishima, Jun Tanimoto, Naoki Ikegaya, Seijiro Mitsuyasu, Stochastic characteristics of thermal load in a single dwelling in a residential building based on building energy simulation coupled with a sub-model for considering variation in behavior schedules of residents, 13th Conference of the International Building Performance Simulation Association, BS 2013 Proceedings of BS 2013: 13th Conference of the International Building Performance Simulation Association, 1446-1450, 2013, The stochastic characteristics of the heating/cooling load of a dwelling in a residential building were investigated using time-series data estimated by Total Utility Demand Prediction System TUD-PS which can predict utility demand such as air-conditioning loads considering the time-varying behavior schedule of residents. The simulation results for 16 cases of different conditions of family type and dwelling indicates the universality of the probability density functions of heating/cooling load..
105. Azli Abd Razak, Aya Hagishima, Naoki Ikegaya, Jun Tanimoto, Analysis of airflow over building arrays for assessment of urban wind environment, Building and Environment, 10.1016/j.buildenv.2012.08.007, 59, 56-65, 2013.01, Large eddy simulation (LES) of the airflows around various types of block arrays was performed to estimate the pedestrian wind environment. Five types of uniform staggered block arrays with different aspect ratios and an array with a nonuniform height were selected for the simulations. The simulation accuracy was validated by comparing the drag coefficient and wind profiles with those of previous work. The characteristics of the spatially averaged mean wind profiles of the arrays were analyzed on the basis of the calculation results. This study reveals that the frontal area ratio, which is the product of the plan area ratio and building aspect ratio, is the most important parameter in estimating the pedestrian wind environment. In addition, a simple exponential equation was derived for predicting the pedestrian wind speed as a function of the frontal area ratio, which is applicable to various building aspect ratios and amounts of height variability..
106. Minsun Park, Aya Hagishima, Jun Tanimoto, Chungyoon Chun, Willingness to pay for improvements in environmental performance of residential buildings, Building and Environment, 10.1016/j.buildenv.2012.10.017, 60, 225-233, 2013.02, The aim of this study is to determine preferences for the environmental factors of residential buildings by using two different methods: the conjoint analysis and ranking method. We tried to identify consumers' monetary value regarding environmental performance by testing their Marginal Willing to Pay (MWTP). A survey was conducted in Seoul, Korea to clarify the preference and monetary value of four selected attributes representing environmental performance. These attributes are reduction of energy bills, reduction of CO2 emissions, reduction of volatile organic compound emissions, and application of information technology facilities. The result can be summarized as follows. The MWTP for 1% reduction of CO2 emission is estimated about $377 USD, being 2 times higher than that for reduction of VOC emissions and almost same as that for the reduction of energy bills. The energy bill is most preferred and IT facilities are least preferred in ranking method. Preferences vary according to respondents' socio-demographic factors and the numerical information in conjoint analysis makes strongly reflect them..
107. Jun Tanimoto, Difference of reciprocity effect in two coevolutionary models of presumed two-player and multiplayer games, Physical Review E - Statistical, Nonlinear, and Soft Matter Physics, 10.1103/PhysRevE.87.062136, 87, 6, 2013.06, Unlike other natural network systems, assortativity can be observed in most human social networks; however, it has been reported that a social dilemma situation represented by a 2×2 prisoner's dilemma game favors dissortativity to enhance cooperation. Our simulations successfully reveal that a public goods game with coevolution for both agents' strategy and network topology encourages assortativity, although it only slightly enhances cooperation as compared to a 2×2 donor and recipient game with a strong dilemma to be solved. This outcome occurs because the network dynamics in a multiplayer game discourages emerging cooperation unlike its beneficial result in a 2×2 prisoner's dilemma game..
108. Kohei Miyaji, Zhen Wang, Jun Tanimoto, Aya Hagishima, Satoshi Kokubo, The evolution of fairness in the coevolutionary ultimatum games, Chaos, Solitons and Fractals, 10.1016/j.chaos.2013.05.007, 56, 13-18, 2013.07, In the ultimatum games, two players are required to split a certain sum of money. Through the responder accepting the offer of proposer, the money will be shared and the fairness is built finally. Here, we figure out five coevolutionary protocols, where strategy (offering rate p and threshold for accepting an offer q) and underlying network topology can coevolve, to demonstrate how the link severing scenario affects the evolution of fairness. We show that the equilibrium of the games is significantly influenced by these coevolutionary protocols. The deterministic rules lead to overly lavish or overly generous result that is inconsistent with the outcome of human behavior experiment. However, the probabilistic rules produce fair division, similar to the realistic case. Moreover, we also introduce an amplitude parameter b to verify the plausibility of assumed link severing protocols. By means of enhancing b we analytically exhibit that preferable performance can be obtained in the game, since the total amount of agents increases as well. Last, we further support our conclusion by showing the so-called unrealistic severing events under these coevolution scenarios. We thus present a viable way of understanding the ubiquitous fairness in nature and hope that it will inspire further studies to resolve social division..
109. Jun Tanimoto, Coevolutionary, coexisting learning and teaching agents model for prisoner's dilemma games enhancing cooperation with assortative heterogeneous networks, Physica A: Statistical Mechanics and its Applications, 10.1016/j.physa.2013.02.004, 392, 13, 2955-2964, 2013.07, Unlike other natural network systems, assortativity can be observed in most human social networks, although it has been reported that a social dilemma situation represented by the prisoner's dilemma favors dissortativity to enhance cooperation. We established a new coevolutionary model for both agents' strategy and network topology, where teaching and learning agents coexist. Remarkably, this model enables agents' enhancing cooperation more than a learners-only model on a time-frozen scale-free network and produces an underlying assortative network with a fair degree of power-law distribution. The model may imply how and why assortative networks are adaptive in human society..
110. Kohei Miyaji, Jun Tanimoto, Zhen Wang, Aya Hagishima, Naoki Ikegaya, Direct Reciprocity in Spatial Populations Enhances R-Reciprocity As Well As ST-Reciprocity, PLoS One, 10.1371/journal.pone.0071961, 8, 8, 2013.08, As is well-known, spatial reciprocity plays an important role in facilitating the emergence of cooperative traits, and the effect of direct reciprocity is also obvious for explaining the cooperation dynamics. However, how the combination of these two scenarios influences cooperation is still unclear. In the present work, we study the evolution of cooperation in 2×2 games via considering both spatial structured populations and direct reciprocity driven by the strategy with 1-memory length. Our results show that cooperation can be significantly facilitated on the whole parameter plane. For prisoner's dilemma game, cooperation dominates the system even at strong dilemma, where maximal social payoff is still realized. In this sense, R-reciprocity forms and it is robust to the extremely strong dilemma. Interestingly, when turning to chicken game, we find that ST-reciprocity is also guaranteed, through which social average payoff and cooperation is greatly enhanced. This reciprocity mechanism is supported by mean-field analysis and different interaction topologies. Thus, our study indicates that direct reciprocity in structured populations can be regarded as a more powerful factor for the sustainability of cooperation..
111. Noriyuki Kishimoto, Satoshi Kokubo, Jun Tanimoto, Combination of continuous and binary strategies enhances network reciprocity in a spatial prisoner's dilemma game, Chaos, Solitons and Fractals, 10.1016/j.chaos.2013.07.009, 56, 83-90, 2013.08, For 2 × 2 games, especially the Spatial Prisoner's Dilemma (SPD), most previous studies have presumed that players can either cooperate (C) or defect (D); this is the so-called discrete strategy. In this paper, we define the continuous-binary strategy instead of the discrete strategy. A systematic series of numerical simulations reports that the continuous-binary strategy enhances the network reciprocity for SPD. This new strategy is based on our previous finding that continuous and mixed strategies shows more robust cooperation than discrete strategy does in boundary games of Chicken and PD (BCH) and Stag Hunt and PD (BSH), respectively. It allows us to combine the advantages of continuous and mixed strategies over the usual discrete strategy into one model..
112. Zhen Wang, Satoshi Kokubo, Jun Tanimoto, Eriko Fukuda, Keizo Shigaki, Insight into the so-called spatial reciprocity, Physical Review E - Statistical, Nonlinear, and Soft Matter Physics, 10.1103/PhysRevE.88.042145, 88, 4, 2013.10, Up to now, there have been a great number of studies that demonstrate the effect of spatial topology on the promotion of cooperation dynamics (namely, the so-called "spatial reciprocity"). However, most researchers probably attribute it to the positive assortment of strategies supported by spatial arrangement. In this paper, we analyze the time course of cooperation evolution under different evolution rules. Interestingly, a typical evolution process can be divided into two evident periods: the enduring (END) period and the expanding (EXP) period where the former features that cooperators try to endure defectors' invasion and the latter shows that perfect C clusters fast expand their area. We find that the final cooperation level relies on two key factors: the formation of the perfect C cluster at the end of the END period and the expanding fashion of the perfect C cluster during the EXP period. For deterministic rule, the smooth expansion of C cluster boundaries enables cooperators to reach a dominant state, whereas, the rough boundaries for stochastic rule cannot provide a sufficient beneficial environment for the evolution of cooperation. Moreover, we show that expansion of the perfect C cluster is closely related to the cluster coefficient of interaction topology. To some extent, we present a viable method for understanding the spatial reciprocity mechanism in nature and hope that it will inspire further studies to resolve social dilemmas..
113. Keizo Shigaki, Zhen Wang, Jun Tanimoto, Eriko Fukuda, Effect of initial fraction of cooperators on cooperative behavior in evolutionary prisoner's dilemma game, PLoS One, 10.1371/journal.pone.0076942, 8, 11, 2013.11, We investigate the influence of initial fraction of cooperators on the evolution of cooperation in spatial prisoner's dilemma games. Compared with the results of heterogeneous networks, we find that there is a relatively low initial fraction of cooperators to guarantee higher equilibrium cooperative level. While this interesting phenomenon is contrary to the commonly shared knowledge that higher initial fraction of cooperators can provide better environment for the evolution of cooperation. To support our outcome, we explore the time courses of cooperation and find that the whole course can be divided into two sequent stages: enduring (END) and expanding (EXP) periods. At the end of END period, thought there is a limited number of cooperator clusters left for the case of low initial setup, these clusters can smoothly expand to hold the whole system in the EXP period. However, for high initial fraction of cooperators, superfluous cooperator clusters hinder their effective expansion, which induces many remaining defectors surrounding the cooperator clusters. Moreover, through intensive analysis, we also demonstrate that when the tendency of three cooperation cluster characteristics (cluster size, cluster number and cluster shape) are consistent within END and EXP periods, the state that maximizes cooperation can be favored..
114. Kohei Miyaji, Jun Tanimoto, Aya Hagishima, Naoki Ikegaya, Influence of stochastic perturbation of both action updating and strategy updating in mixed-strategy 2 × 2 games on evolution of cooperation, Physical Review E - Statistical, Nonlinear, and Soft Matter Physics, 10.1103/PhysRevE.88.062149, 88, 6, 2013.12, In a mixed-strategy game framework, each agent's strategy is defined by a real number; on the other hand, in a discrete strategy game framework, only binary strategies, either cooperation or defection, are allowed. In a spatial mixed-strategy game, with respect to the process for updating action (offer), either a synchronous or an asynchronous strategy update should be presumed. This study elucidates how stochastic perturbation that results from a synchronous or an asynchronous process for updating action significantly affects the enhancement of cooperation in an evolutionary process. Especially, when a synchronous process for updating action is assumed, the extent of cooperation increases with an increase in degree..
115. Jun Tanimoto, Assortative and dissortative priorities for game interaction and strategy adaptation significantly bolster network reciprocity in the prisoner's dilemma, Journal of Statistical Mechanics: Theory and Experiment, 10.1088/1742-5468/2014/05/P05003, 2014, 5, 2014, In 2 × 2 prisoner's dilemma games, network reciprocity is one mechanism for adding social viscosity, which leads to cooperative equilibrium. Here we show that combining the process for selecting a gaming partner with the process for selecting an adaptation partner significantly enhances cooperation, even though such selection processes require additional costs to collect further information concerning which neighbor should be chosen. Based on elaborate investigations of the dynamics generated by our model, we find that high levels of cooperation result from two kinds of behavior: cooperators tend to interact with cooperators to prevent being exploited by defectors and defectors tend to choose cooperators to exploit despite the possibility that some defectors convert to cooperators..
116. Naoki Ikegaya, Aya Hagishima, Jun Tanimoto, A consideration on the effects of drag force acting on roughness element - The relationship between drag coefficient and dissipation rate, Journal of Environmental Engineering (Japan), 10.3130/aije.79.297, 79, 697, 297-304, 2014, Momentum and energy budgets on an urban surface are investigated based on theoretical approach by deriving the budget equations. Firstly, we have introduced the integral equation for energy, which corresponds to the equation as known as Karman's integral law for momentum. These equations can explain the effect of drag force acting on roughness elements on the budgets of momentum and energy. Secondly, it is shown that the additional term appears to explain for the drag force to be able to directly absorb momentum provided out of boundary layer. Although the corresponding term does not exist in the energy budget equations, the drag force may work to increase the turbulence energy through the additional turbulence production terms. Thirdly, the relationship between drag coefficient and dissipation rate have been discussed. These quantities have positive correlation and can be an index to explain the wind velocity deficit..
117. Jun Tanimoto, Simultaneously selecting appropriate partners for gaming and strategy adaptation to enhance network reciprocity in the prisoner's dilemma, Physical Review E - Statistical, Nonlinear, and Soft Matter Physics, 10.1103/PhysRevE.89.012106, 89, 1, 2014.01, Network reciprocity is one mechanism for adding social viscosity, which leads to cooperative equilibrium in 2 × 2 prisoner's dilemma games. Previous studies have shown that cooperation can be enhanced by using a skewed, rather than a random, selection of partners for either strategy adaptation or the gaming process. Here we show that combining both processes for selecting a gaming partner and an adaptation partner further enhances cooperation, provided that an appropriate selection rule and parameters are adopted. We also show that this combined model significantly enhances cooperation by reducing the degree of activity in the underlying network; we measure the degree of activity with a quantity called effective degree. More precisely, during the initial evolutionary stage in which the global cooperation fraction declines because initially allocated cooperators becoming defectors, the model shows that weak cooperative clusters perish and only a few strong cooperative clusters survive. This finding is the most important key to attaining significant network reciprocity..
118. Eriko Fukuda, Satoshi Kokubo, Jun Tanimoto, Zhen Wang, Aya Hagishima, Naoki Ikegaya, Risk assessment for infectious disease and its impact on voluntary vaccination behavior in social networks, Chaos, Solitons and Fractals, 10.1016/j.chaos.2014.07.004, 68, 1-9, 2014.01, Achievement of the herd immunity is essential for preventing the periodic spreading of an infectious disease such as the flu. If vaccination is voluntary, as vaccination coverage approaches the critical level required for herd immunity, there is less incentive for individuals to be vaccinated; this results in an increase in the number of so-called "free-riders" who craftily avoid infection via the herd immunity and avoid paying any cost. We use a framework originating in evolutionary game theory to investigate this type of social dilemma with respect to epidemiology and the decision of whether to be vaccinated. For each individual in a population, the decision on vaccination is associated with how one assesses the risk of infection. In this study, we propose a new risk-assessment model in a vaccination game when an individual updates her strategy, she compares her own payoff to a net payoff obtained by averaging a collective payoff over individuals who adopt the same strategy as that of a randomly selected neighbor. In previous studies of vaccination games, when an individual updates her strategy, she typically compares her payoff to the payoff of a randomly selected neighbor, indicating that the risk for changing her strategy is largely based on the behavior of one other individual, i.e., this is an individual-based risk assessment. However, in our proposed model, risk assessment by any individual is based on the collective success of a strategy and not on the behavior of any one other individual. For strategy adaptation, each individual always takes a survey of the degree of success of a certain strategy that one of her neighbors has adopted, i.e., this is a strategy-based risk assessment. Using computer simulations, we determine how these two different risk-assessment methods affect the spread of an infectious disease over a social network. The proposed model is found to benefit the population, depending on the structure of the social network and cost of vaccination. Our results suggest that individuals (or governments) should understand the structure of their social networks at the regional level, and accordingly, they should adopt an appropriate risk-assessment methodology as per the demands of the situation..
119. Sheikh Ahmad Zaki, Aya Hagishima, Jun Tanimoto, Ahmad Faiz Mohammad, Azli Abd Razak, Estimation of aerodynamic parameters of urban building arrays using wind tunnel measurements, Journal of Engineering Science and Technology, 9, 2, 176-190, 2014.04, The aim of this study is the experimental determination of a centre height of moment of drag force Hc, which is assumed to coincide with displacement height d on the basis of Jackson's theory. The authors performed a series of wind tunnel experiments on the spatial distribution of pressure drag acting on walls of rectangular block arrays arranged in staggered, square, and diamond layouts under the conditions of different roughness packing densities, i.e., 7.7%, 17.4%, 30.9%, and 39.1%. Total drag and wind profile of the arrays were preliminarily measured by a floating drag balance and a hot-wire anemometer, and roughness length zo and d were derived using two-parameter fitting in our previous work. Hc values determined by the pressure drag measurement were compared with d of our previous work. The results show that the estimated Hc values for staggered and square arrays are significantly smaller than d except for the data of lowest packing density. Moreover, the zo values estimated using one-parameter fitting and measured Hc are slightly larger than those of previous work for the three arrays with high packing density. Although inconsistencies of Hc and d exist, it is likely that Hc could be explained as d for a range of low packing densities, i.e., below 30.9%. The present results suggest the necessity of both more accurate data of spatially averaged wind profile and direct measurement of Hc for experimental determination of the roughness length and displacement height of a block array..
120. Jun Tanimoto, Shinji Kukida, Aya Hagishima, Social dilemma structures hidden behind traffic flow with lane changes, Journal of Statistical Mechanics: Theory and Experiment, 10.1088/1742-5468/2014/07/P07019, 2014, 7, 2014.07, Aiming to merge traffic flow analysis with evolutionary gametheory, we investigated the question of whether such structures can be formedfrom frequent lane changes in usual traffic flow without any explicit bottlenecks.In our model system, two classes of driver-agents coexist: C-agents (cooperativestrategy) always remain in the lane they are initially assigned, whereas D-agents(defective strategy) try to change lanes to move ahead. In relatively high-densityflows, such as the metastable and high-density phases, we found structuresthat correspond to either n-person prisoner dilemma (n-PD) games or quasi-PDgames. In these situations, lane changes by D-agents create heavy traffic jamsthat reduce social efficiency..
121. Naoko Konno, Azusa Ono, Akashi Mochida, Takashi Maruyama, Aya Hagishima, Jun Tanimoto, Modelling of canopy flow of the various roughness arrays
Method to determine the model coefficients applicable to staggered roughness arrays with various densities and configurations, Journal of Environmental Engineering (Japan), 79, 702, 699-707, 2014.08, The final goal of this research is to develop a generalized canopy model describing the effects of obstacles with various configurations and densities, such as automobiles and pedestrians on wind environment and turbulent diffusion in urban areas. A series of wind tunnel experiments was carried out to measure wind velocity profiles and drag forces acting on five shapes of roughness elements with different densities. The two of them represented car shapes and the others represented human shapes. CFD predictions were conducted for the equivalent configurations as those implemented in wind tunnel tests. The numerical experiment was conducted by changing the coefficients of the developed canopy model. The model coefficients were optimized by comparing with the experimental data and a new method to determine the model coefficients and definitions of the shape factors applicable to various obstacles were proposed..
122. Jun Tanimoto, Impact of deterministic and stochastic updates on network reciprocity in the prisoner's dilemma game, Physical Review E - Statistical, Nonlinear, and Soft Matter Physics, 10.1103/PhysRevE.90.022105, 90, 2, 2014.08, In 2 × 2 prisoner's dilemma games, network reciprocity is one mechanism for adding social viscosity, which leads to cooperative equilibrium. This study introduced an intriguing framework for the strategy update rule that allows any combination of a purely deterministic method, imitation max (IM), and a purely probabilistic one, pairwise Fermi (Fermi-PW). A series of simulations covering the whole range from IM to Fermi-PW reveals that, as a general tendency, the larger fractions of stochastic updating reduce network reciprocity, so long as the underlying lattice contains no noise in the degree of distribution. However, a small amount of stochastic flavor added to an otherwise perfectly deterministic update rule was actually found to enhance network reciprocity. This occurs because a subtle stochastic effect in the update rule improves the evolutionary trail in games having more stag-hunt-type dilemmas, although the same stochastic effect degenerates evolutionary trails in games having more chicken-type dilemmas. We explain these effects by dividing evolutionary trails into the enduring and expanding periods defined by Shigaki et al. [Phys. Rev. E 86, 031141 (2012)PRESCM1539-375510.1103/PhysRevE.86.031141] ..
123. Jun Tanimoto, Dynamics of spatial traveler's dilemma games, Journal of Statistical Mechanics: Theory and Experiment, 10.1088/1742-5468/2014/11/P11010, 2014, 11, 2014.11, By examining payoff structures, we elucidate the traveler's dilemma (TD) game. It can be said that the TD game as the 2-player & multi-strategy game is a variant of the donor & recipient game, which itself is a subclass of the 2-player & 2-strategy (2 x 2) prisoner's dilemma, in the sense that the Nash equilibrium and fair Pareto optimum appear on mutual defection and mutual cooperation, respectively. Exploring spatial TD games, we observed that the network reciprocity of TD games can be universally scaled with a single dilemma parameter as can be performed in usual 2 x 2 games. Furthermore, we observed a local peak event reflecting a resurging cooperation fraction with increasing dilemma strength after degradation to a low level. We successfully demonstrate that this is caused by the specific dynamics of TD games created by their specific payoff structure..
124. Jun Tanimoto, Takuya Fujiki, Zhen Wang, Aya Hagishima, Naoki Ikegaya, Dangerous drivers foster social dilemma structures hidden behind a traffic flow with lane changes, Journal of Statistical Mechanics: Theory and Experiment, 10.1088/1742-5468/2014/11/P11027, 2014, 11, 2014.11, Motivated by the fact that there are quite a few ill-mannered drivers who disregard traffic rules concerning lane-changing and maximum speed, we investigated an interesting question: whether or not social dilemma structures can be formed from a frequent dangerous lane-changing attitude in a typical traffic flow without any explicit bottlenecks. In our model system, two classes of driver-agents coexist: C agents (cooperative strategy) always keep to traffic regulations with respect to lane-changing and speed, while D agents (defective strategy) disregard them to move ahead. In relatively high-density flows, such as the metastable and high-density phases, we found structures that correspond to either n-person Prisoner's Dilemma (n-PD) games or to quasi-PD games. In these situations, existing ill-mannered drivers create heavy traffic jams that reduce social efficiency..
125. Takashi Ogasawara, Jun Tanimoto, Eriko Fukuda, Aya Hagishima, Naoki Ikegaya, Effect of a large gaming neighborhood and a strategy adaptation neighborhood for bolstering network reciprocity in a prisoner's dilemma game, Journal of Statistical Mechanics: Theory and Experiment, 10.1088/1742-5468/2014/12/P12024, 2014, 12, 2014.12, In 22 prisoner's dilemma (PD) games, network reciprocity is one mechanism for adding social viscosity, leading to a cooperative equilibrium. In this paper, we explain how gaming neighborhoods and strategy-adaptation neighborhoods affect network reciprocity independently in spatial PD games. We explore an appropriate range of strategy adaptation neighborhoods as opposed to the conventional method of making the gaming and strategy adaptation neighborhoods coincide to enhance the level of cooperation. In cases of expanding gaming neighborhoods, network reciprocity falls to a low level relative to the conventional setting. In the discussion below, which is based on the results of our simulation, we explore how these enhancements come about. Essentially, varying the range of the neighborhoods influences how cooperative clusters form and expand in the evolutionary process..
126. Yasuaki Ikeda, Aya Hagishima, Naoki Ikegaya, Jun Tanimoto, Azli Abd Razak, Estimation of wind speed in urban pedestrian spaces on the basis of large-eddy simulation, Journal of Environmental Engineering (Japan), 80, 709, 259-267, 2015, The wind speeds in pedestrian spaces for staggered rectangular block arrays derived from large-eddy simulations are analyzed to model the urban pedestrian wind environment. The authors defined the area within 3 m of block walls as the pedestrian space and compared wind speeds in it under various geometric conditions. According to the result, the wind speeds in pedestrian spaces are influenced by the plan area ratio (λp) and block aspect ratio (αp). In addition, an exponential equation in terms of λp and αp can estimate the wind speed ratio well at the pedestrian level, especially for regions in front of blocks..
127. Zhen Wang, Satoshi Kokubo, Marko Jusup, Jun Tanimoto, Universal scaling for the dilemma strength in evolutionary games, Physics of Life Reviews, 10.1016/j.plrev.2015.04.033, 14, 1-30, 2015.01, Why would natural selection favor the prevalence of cooperation within the groups of selfish individuals? A fruitful framework to address this question is evolutionary game theory, the essence of which is captured in the so-called social dilemmas. Such dilemmas have sparked the development of a variety of mathematical approaches to assess the conditions under which cooperation evolves. Furthermore, borrowing from statistical physics and network science, the research of the evolutionary game dynamics has been enriched with phenomena such as pattern formation, equilibrium selection, and self-organization. Numerous advances in understanding the evolution of cooperative behavior over the last few decades have recently been distilled into five reciprocity mechanisms: direct reciprocity, indirect reciprocity, kin selection, group selection, and network reciprocity. However, when social viscosity is introduced into a population via any of the reciprocity mechanisms, the existing scaling parameters for the dilemma strength do not yield a unique answer as to how the evolutionary dynamics should unfold. Motivated by this problem, we review the developments that led to the present state of affairs, highlight the accompanying pitfalls, and propose new universal scaling parameters for the dilemma strength. We prove universality by showing that the conditions for an ESS and the expressions for the internal equilibriums in an infinite, well-mixed population subjected to any of the five reciprocity mechanisms depend only on the new scaling parameters. A similar result is shown to hold for the fixation probability of the different strategies in a finite, well-mixed population. Furthermore, by means of numerical simulations, the same scaling parameters are shown to be effective even if the evolution of cooperation is considered on the spatial networks (with the exception of highly heterogeneous setups). We close the discussion by suggesting promising directions for future research including (i) how to handle the dilemma strength in the context of co-evolution and (ii) where to seek opportunities for applying the game theoretical approach with meaningful impact..
128. Naoki Ikegaya, Juyeon Chung, Aya Hagishima, Jun Tanimoto, Similarity between velocity and scalar profiles over cubical block array, Journal of Environmental Engineering (Japan), 10.3130/aije.80.451, 80, 711, 451-459, 2015.01, We have performed wind-tunnel experiments to measure velocity and scalar concentration profiles over urban-like roughness arrays and reveal important characteristics of scalar dispersion in the boundary layer over rough wall as follows. First, comparison of profiles reveals that the scalar concentration boundary layer depth reaches almost consistent depth of momentum boundary layer, meaning that scalar is passively transported or diffused in boundary layer. In addition, the development of the boundary layer is steeper than that of smooth surface. Secondly, aerodynamic parameters, such as roughness length and displacement height are determined for both momentum and scalar. It reveals that the roughness length of scalar is smaller than that of momentum by the order of 10-2 and can be well estimated by well-known scale-similarity model. Thirdly, roughness function of the momentum and scalar are determined and compared with several previous results. The roughness function of scalar for the present study lies between that of smooth and rough wall because of scale effect of scalar and decrease of Re number dependency..
129. Jun Tanimoto, Takashi Ogasawara, Dynamic noise from action errors enhances network reciprocity in the prisoner's dilemma game, Journal of Statistical Mechanics: Theory and Experiment, 10.1088/1742-5468/2015/01/P01033, 2015, 1, 2015.01, Inspired by the fact that people make mistakes in a transient, fluctuating or chaotic environment, we establish a spatial prisoner's dilemma model where an agent commits action errors proportionally varying with the increasing/decreasing rate of the global cooperation fraction. A series of numerical simulations reveal that the cooperation level is enhanced in games in which the stag hunt (SH)-type dilemma is dominant; however, it is slightly diminished in games in which the chicken-type dilemma is dominant, compared with the standard network reciprocity model. Intensive analysis reveals that the noise created by the action error contribute to the spatial expansion of a cooperators' cluster, because a dilemma that is less chicken-type and more SH-type makes it disadvantageous for defectors to neighbor cooperators. Our finding, that errors in behavior in a chaotic environment contribute to the evolution of cooperation, might aim to explain the problem of how network reciprocity works..
130. Jun Tanimoto, Takuya Fujiki, Shinji Kukida, Naoki Ikegaya, Aya Hagishima, Acquisition of the field measurement data relating to lane change actions, International Journal of Modern Physics C, 10.1142/S0129183115500722, 26, 7, 2015.01, As a data set for validation of microscopic simulation models, we obtained the fundamental diagram (flux versus density relation), and the relations of velocity versus density, lane usage ratio versus density and lane-changing frequency versus density derived from a single field measurement campaign held at a Japanese urban expressway. The results were drawn from image analysis of video camera data obtained at the site..
131. Jun Tanimoto, Nobuyuki Kishimoto, Network reciprocity created in prisoner's dilemma games by coupling two mechanisms, Physical Review E - Statistical, Nonlinear, and Soft Matter Physics, 10.1103/PhysRevE.91.042106, 91, 4, 2015.04, We found that a nontrivial enhancement of network reciprocity for 2 × 2 prisoner's dilemma games can be achieved by coupling two mechanisms. The first mechanism presumes a larger strategy update neighborhood than the conventional first neighborhood on the underlying network. The second is the strategy-shifting rule. At the initial time step, the averaged cooperation extent is assumed to be 0.5. In the case of strategy shifting, an agent adopts a continuous strategy definition during the initial period of a simulation episode (when the global cooperation fraction decreases from its initial value of 0.5; that is, the enduring period). The agent then switches to a discrete strategy definition in the time period afterwards (when the global cooperation fraction begins to increase again; that is, the expanding period). We explored why this particular enhancement comes about, and to summarize, the continuous strategy during the initial period relaxes the conditions for the survival of relatively cooperative clusters, and the large strategy adaptation neighborhood allows those cooperative clusters to expand easily..
132. Jun Tanimoto, The impact of initial cooperation fraction on the evolutionary fate in a spatial prisoner's dilemma game, Applied Mathematics and Computation, 10.1016/j.amc.2015.04.043, 263, 171-188, 2015.05, Abstract Although the initial cooperation fraction and its arrangement obviously impacts the equilibrium in spatial prisoner's dilemma (SPD) games, most of the previous studies relying on a simulation approach have by conformity assumed a value of 0.5, thus implying an equal distribution of cooperators and defectors as the established premise. This study first points out that depending on target applications, i.e., biological or general evolutionary dynamical systems, we must select the initial cooperation fraction and its spatial distribution carefully to avoid a misleading conclusion. On the basis of comprehensive numerical experiments and a deductive discussion, wherein both the rule of strategy update and the underlying network are varied, we present a panoramic view of the effects of initial cooperation settings on evolutionary dynamics. Several non-trivial findings are revealed concerning the different impacts of deterministic or stochastic updating, or of homogeneous or heterogeneous underlying topology on evolutionary dynamics..
133. Satoshi Kokubo, Zhen Wang, Jun Tanimoto, Spatial reciprocity for discrete, continuous and mixed strategy setups, Applied Mathematics and Computation, 10.1016/j.amc.2015.03.018, 259, 552-568, 2015.05, The existence of cooperation in the social dilemma has been extensively studied based on spatial structure populations, namely, the so-called spatial reciprocity. However, vast majority of existing works just simply presume that agents can offer the discrete choice: either the cooperative (C) or defective (D) strategy, which, to some extent, seems unrealistic in the empirical observations since actual options might be continuous, mixed rather than discrete. Here, we propose discrete, continuous and mixed strategy setups in the social dilemma games and further explore their performance on network populations. Interestingly, it is unveiled that there is actually considerable inconsistency in terms of equilibrium among different strategy games. Furthermore, we reveal how different cooperative arrangements among these three strategy setups can be established, depending on whether the presumed dilemma subclass is a boundary game between prisoner's dilemma game and Chicken game or between prisoner's dilemma game and Stag-Hunt game..
134. Eriko Fukuda, Jun Tanimoto, Mitsuhiro Akimoto, Influence of breaking the symmetry between disease transmission and information propagation networks on stepwise decisions concerning vaccination, Chaos, Solitons and Fractals, 10.1016/j.chaos.2015.04.018, 80, 47-55, 2015.06, In previous epidemiological studies that address adaptive vaccination decisions, individuals generally act within a single network, which models the population structure. However, in reality, people are typically members of multiplex networks, which have various community structures. For example, a disease transmission network, which directly transmits infectious diseases, does not necessarily correspond with an information propagation network, in which individuals directly or indirectly exchange information concerning health conditions and vaccination strategies. The latter network may also be used for strategic interaction (strategy adaptation) concerning vaccination. Therefore, in order to reflect this feature, we consider the vaccination dynamics of structured populations whose members simultaneously belong to two types of networks: disease transmission and information propagation. Applying intensive numerical calculations, we determine that if the disease transmission network is modeled using a regular graph, such as a lattice population or random regular graph containing individuals of equivalent degrees, individuals should base their vaccination decisions on a different type of network. However, if the disease transmission network is a degree-heterogeneous graph, such as the Barabási-Albert scale-free network, which has a heterogeneous degree according to power low, then using the same network for information propagation more effectively prevents the spread of epidemics. Furthermore, our conclusions are unaffected by the relative cost of vaccination..
135. Jun Tanimoto, Considering individual satisfaction levels enhances cooperation in a spatial prisoner's dilemma game, Chaos, Solitons and Fractals, 10.1016/j.chaos.2015.02.025, 80, 24-30, 2015.06, Based on the observance in human society, the satisfaction level of an individual as a result of an obtained payoff depends on personal tendency to some extent; we establish a new model for spatial prisoner's dilemma games. We describe individual satisfaction as a stochastically deviated value around each of the four payoffs stipulated by a payoff matrix, which is maintained throughout the life of a certain agent. When strategy updating, an agent who refers to his own satisfaction level cannot see neighbors' satisfaction levels but can only observe neighbors' accumulated payoffs. By varying the update rule and underlying topology, we perform numerical simulations that reveal cooperation is significantly enhanced by this change. We argue that this enhancement of cooperation is analogous to a stochastic resonance effect, like the payoff noise effects Perc (2006)..
136. Jun Tanimoto, Hirokji Sagara, How the indirect reciprocity with co-evolving norm and strategy for 2 × 2 prisoner's dilemma game works for emerging cooperation, Physica A: Statistical Mechanics and its Applications, 10.1016/j.physa.2015.07.006, 438, 595-602, 2015.08, We built a new indirect reciprocity model based on binary image scores, where an agent's strategy and norm co-evolve. The norm, meaning what behavior is evaluated as "good" or "bad," stipulates how image scores of two agents playing a game is altered, which has been presumed to be a fixed value in most previous studies. Also, unlike former studies, our model allows an agent to play with an agent who has a different norm. This point of relaxing the freedom of the model pulls down cooperation level vis-à-vis the case where an agent always plays with another one having same norm. However, it is observed that a rather larger dilemma shows robust cooperation establishing compared with a smaller dilemma, since a norm that punishes a so-called second-order free-rider is prompted. To encourage the evolution of norms to be able to punish second-order free-riders, a society needs a small number of defectors. This is elucidated by the fact that cases with action error are more cooperative than those without action error..
137. Zhen Wang, Satoshi Kokubo, Marko Jusup, Jun Tanimoto, Dilemma strength as a framework for advancing evolutionary game theory. Reply to comments on "Universal scaling for the dilemma strength in evolutionary games"., Physics of Life Reviews, 10.1016/j.plrev.2015.07.012, 14, 56-58, 2015.09.
138. Juyeon Chung, Aya Hagishima, Naoki Ikegaya, Jun Tanimoto, Wind-Tunnel Study of Scalar Transfer Phenomena for Surfaces of Block Arrays and Smooth Walls with Dry Patches, Boundary-Layer Meteorology, 10.1007/s10546-015-0063-3, 157, 2, 219-236, 2015.11, We report the result of a wind-tunnel experiment to measure the scalar transfer efficiency of three types of surfaces, wet street surfaces of cube arrays, wet smooth surfaces with dry patches, and fully wet smooth surfaces, to examine the effects of roughness topography and scalar source allocation. Scalar transfer coefficients defined by the source area CEwet for an underlying wet street surface of dry block arrays show a convex trend against the block density λp. Comparison with past data, and results for wet smooth surfaces including dry patches, reveal that the positive peak of CEwet with increasing λp is caused by reduced horizontal advection due to block roughness and enhanced evaporation due to a heterogeneous scalar source distribution. In contrast, scalar transfer coefficients defined by a lot-area including wet and dry areas CElot for smooth surfaces with dry patches indicate enhanced evaporation compared to the fully wet smooth surface (the oasis effect) for all three conditions of dry plan-area ratio up to 31 %. Relationships between the local Sherwood and Reynolds numbers derived from experimental data suggest that attenuation of CEwet for a wet street of cube arrays against streamwise distance is weaker than for a wet smooth surface because of canopy flow around the blocks. Relevant parameters of ratio of roughness length for momentum to scalar B-1 were calculated from observational data. The result implies that B-1 possibly increases with block roughness, and decreases with the partitioning of the scalar boundary layer because of dry patches..
139. Jun Tanimoto, Correlated asynchronous behavior updating with a mixed strategy system in spatial prisoner's dilemma games enhances cooperation, Chaos, Solitons and Fractals, 10.1016/j.chaos.2015.03.021, 80, 39-46, 2015.11, A new model of mixed strategy system for spatial prisoner's dilemma games is proposed. As an alternative to the typical mixed strategy system, wherein a behavior of either cooperation or defection is stochastically determined for each neighbor based on the agent's overall strategy, in our mixed strategy system, the agent instead correlates his strategies with those of his neighbors. For example, he tends to offer cooperation more frequently to his neighbor who is cooperative more often. This model provides results with significantly enhanced cooperation compared with those obtained with the conventional mixed strategy model. Interestingly, some of the evolutionary paths followed under strong dilemma situations can be divided into two specific periods: Defector-Enduring (D-END), when the number of defectors rapidly decreases, and the subsequent Defector-Expanding (D-EXP), when the surviving defectors' clusters start to expand, allowing the global cooperation fraction to fall to a lower level. The D-END and D-EXP periods seem analogous to the END and EXP periods presented by the author in previous studies..
140. Tsuyoshi Sato, Aya Hagishima, Naoki Ikegaya, Jun Tanimoto, Wind tunnel experiment on turbulent flow field around 2D street canyon with eaves, Journal of Environmental Engineering (Japan), 10.3130/aije.81.467, 81, 723, 467-476, 2016.05, In this study, the influence of the complexity of shape of roughness on turbulent flow fields in a 2D street canyon was investigated using a wind tunnel experiment (WTE). Time-resolved particle image velocimetry (TR-PIV) was employed to investigate temporally averaged flow fields, the spatial distributions of turbulent statistics, canyon ventilation rates, and the flow exchange mechanism between the regions above and inside a canyon. The measurements revealed that the temporally averaged flow fields and the spatial distributions of turbulent statistics are drastically changed by the complexity of roughness, especially when the canyon aspect ratio is small. Moreover, the ventilation rate is reduced by the eaves attached to roofs. However, the decreasing rate of the ventilation strongly depends on the canyon aspect ratio..
141. Naoki Ikegaya, C. Hirose, Aya Hagishima, Jun Tanimoto, Effect of turbulent flow on wall pressure coefficients of block arrays within urban boundary layer, Building and Environment, 10.1016/j.buildenv.2016.02.005, 100, 28-39, 2016.05, Various numerical simulations have been developed to evaluate the mean ventilation rates of a target building; however, the manner in which turbulent flow generated by buildings and surrounding conditions affects the mean and fluctuating ventilation rates is not well understood. Therefore, we have performed large-eddy simulation of flow and pressure fields above two types of block arrays (lattice-type square and staggered pattern) to clarify the turbulent characteristics of estimated ventilation rates based on pressure coefficient distribution on the block faces. The concept of short-term ventilation rates, which are estimated from filtered pressure coefficients, is introduced to investigate the temporal variation in the estimated ventilation rates for different locations of the block faces and arrangements. First, mean and second-order turbulent statistics agree well with previous results obtained from both wind-tunnel experiments and numerical simulations, indicating that the turbulent characteristics of the flow above urban-like arrays are well reproduced. Second, short-term ventilation rates are found to vary temporally and spatially. Therefore, these values instantaneously become larger or smaller than the mean ventilation rates. In addition, complex fluctuation patterns of pressure coefficient distribution are found to be caused by air flow introduction from the block arrays into gaps between the blocks as well as by small-scale turbulence generated by surrounding buildings themselves. Lastly, the temporal statistics of filtered pressure coefficients show that the short-term ventilation rates can possibly become stronger or weaker than the mean ventilation rates, whereas the accumulated fluctuating ventilation rates are almost comparable to those estimated by mean pressure coefficients..
142. Ryo Matsuzawa, Jun Tanimoto, Eriko Fukuda, Spatial prisoner's dilemma games with zealous cooperators, Physical Review E, 10.1103/PhysRevE.94.022114, 94, 2, 2016.08, The existence of a zealot who stays a cooperator irrespective of the result of an interaction has been reported to add "social viscosity" to a population and thereby helps increase the cooperation level in prisoner's dilemma games, which premises the so-called well-mixed situation of a population. We found that this is not always true when a spatial structure, i.e., connecting agent, is introduced. Deploying zealots is counterproductive, especially when the underlying topology is homogenous, similar to that of a lattice. Our simulation reveals how the existence of never-converting cooperators destroys rather than boosts cooperation. We explain detailed mechanisms behind this interesting finding by referring to our previously presented concepts with respect to evolutionary dynamic processes for spatial games under the names enduring and expanding periods..
143. Yoshiro Iwamura, Jun Tanimoto, Eriko Fukuda, Effect of intermediate defense measures in voluntary vaccination games, Journal of Statistical Mechanics: Theory and Experiment, 10.1088/1742-5468/2016/09/093501, 2016, 9, 2016.09, We build a model to reproduce the decision-making process of getting a vaccination based on the evolutionary game theory dovetailed with the SIR model for epidemic spreading. Unlike the two extreme options of whether or not getting a vaccination leads to perfect immunity, we consider whether 'intermediate defense measures' including masking, gargling, and hand-washing lead to imperfect effects of preventing infection. We consider introducing not only a 'third strategy' as a discrete intermediate measure but also a continuous strategy space connecting the cases of getting and not getting a vaccination. Interestingly, our evolutionary analysis suggests that the introduction of intermediate measures makes no difference for the case of a 2-strategy system in which only either getting or not getting a vaccination is allowed, even does not ameliorate, or say, gets worse to prevent spreading a disease. This seems quite different from what was observed in 2-player and 2-strategy (2 × 2) prisoner's dilemma (PD) games with relatively stronger chicken-type dilemma than the stag-hunt one in which the introduction of middle-course strategies significantly enhances cooperation..
144. Jun Tanimoto, Kousuke Nakamura, Social dilemma structure hidden behind traffic flow with route selection, Physica A: Statistical Mechanics and its Applications, 10.1016/j.physa.2016.04.023, 459, 92-99, 2016.10, Several traffic flows contain social dilemma structures. Herein, we explored a route-selection problem using a cellular automaton simulation dovetailed with evolutionary game theory. In our model, two classes of driver-agents coexist: D agents (defective strategy), which refer to traffic information for route selection to move fast, and C agents (cooperative strategy), which are insensitive to information and less inclined to move fast. Although no evidence suggests that the social dilemma structure in low density causes vehicles to move freely and that in high density causes traffic jams, we found a structure that corresponds to an n-person (multiplayer) Chicken (n-Chicken) game if the provided traffic information is inappropriate. If appropriate traffic information is given to the agents, the n-Chicken game can be solved. The information delivered to vehicles is crucial for easing the social dilemma due to urban traffic congestion when developing technologies to support the intelligent transportation system (ITS)..
145. Jun Tanimoto, A multi-community homogeneous small-world network and its fundamental characteristics, Physica A: Statistical Mechanics and its Applications, 10.1016/j.physa.2016.04.044, 460, 88-97, 2016.10, We introduce a new small-world network-which we call the multi-community homogeneous-small-world network-that is divided into multiple communities that are relatively isolated, similar to sparsely connected islands. A generating algorithm is presented and its network parameters are explored. To elucidate the fundamental characteristics of the proposed topology, we adopt spatial prisoner's dilemma games as a template for discussion. Comparing with a conventional homogeneous small-world network, more enhanced network reciprocity is observed in games where a stag hunt-type dilemma is large. With intensive analysis, we find how this enhancement is brought about..
146. Eriko Fukuda, Jun Tanimoto, Yoshiro Iwamura, Kosuke Nakamura, Akimoto Mitsuhiro, Field measurement analysis to validate lane-changing behavior in a cellular automaton model, Physical Review E - Statistical, Nonlinear, and Soft Matter Physics, 10.1103/PhysRevE.94.052209, 94, 5, 2016.11, In the present study, we analyzed field measurement data obtained for a Japanese expressway and used it as a data set for the validation of microscopic simulation models. Consequently, in accordance with previous studies, we confirmed the common features depicted by the fundamental diagram (flux vs density relation) and lane-usage ratio vs density diagram. We found two things regarding lane-changing behavior: (1) a lane change occurs asymmetrically, where a lane change from a slow to a fast lane differs from that from a fast to a slow lane; and (2) the so-called incentive criterion in the case of small gaps between the preceding vehicles in both slow and fast lanes refers to the velocities and /or the relative velocities with respect to the preceding vehicles, whereas that for relatively large gaps refers to the distances to the preceding vehicles is cast into the above incentive criterion in addition to the two factors mentioned above..
147. Jun Tanimoto, Enhancement of cooperation in the spatial prisoner's dilemma with a coherence-resonance effect through annealed randomness at a cooperator–defector boundary; comparison of two variant models, Physica A: Statistical Mechanics and its Applications, 10.1016/j.physa.2016.06.002, 462, 714-724, 2016.11, Inspired by the commonly observed real-world fact that people tend to behave in a somewhat random manner after facing interim equilibrium to break a stalemate situation whilst seeking a higher output, we established two models of the spatial prisoner's dilemma. One presumes that an agent commits action errors, while the other assumes that an agent refers to a payoff matrix with an added random noise instead of an original payoff matrix. A numerical simulation revealed that mechanisms based on the annealing of randomness due to either the action error or the payoff noise could significantly enhance the cooperation fraction. In this study, we explain the detailed enhancement mechanism behind the two models by referring to the concepts that we previously presented with respect to evolutionary dynamic processes under the names of enduring and expanding periods..
148. Ryo Matsuzawa, Jun Tanimoto, A social dilemma structure in diffusible public goods, Europhysics Letters, 10.1209/0295-5075/116/38005, 116, 3, 2016.11, Encouraged by the interaction between two species of microbes, in which one species is capable of replenishing the public resources and the other is not, the dilemma structure (the long-term sustainability of the population) hidden in a system where public goods are defined as diffusible was examined. In a series of simulations in which the three major parameters governing the dynamics of the system were varied, following the effect of the spatial structure that results from resource diffusion and distribution, the dynamics show a rich diversity, including cooperator-dominated, extinct, and coexistent results. If the dilemma is strong, the chance of surviving cooperators is small and the population tends to extinction even though coexistence is possible. By contrast, if a weak dilemma is given, the affluent resources make cooperators dominant over defectors..
149. Naoki Ikegaya, Yasuaki Ikeda, Aya Hagishima, Jun Tanimoto, Statistical analysis of wind speeds at a pedestrian level of urban-like roughness, Journal of Wind Engineering, 10.5359/jwe.42.1, 42, 1, 1-8, 2017.01, We have performed Large-Eddy Simulation of turbulent boundary layer over simplified urban like roughness. Totally six types of arrays are adopted with several roughness densities and roughness aspect ratios. The turbulent flow fields at a pedestrian level are investigated to identify probability characteristics of unsteady flows. Conclusions are summarized as follows. First, the probability density functions of wind speeds at a pedestrian level show long-tail shape with positive skewness for all arrays and well explained by dimensionless probability variable defined by the mean and standard deviation of wind speeds. On the other hands, the discrepancies of the probability between arrays become considerable for events with wind speeds larger than triple of the standard deviations. Second, such events with large wind speed rarely happen; the cumulative probability shows approximately 1%. Lastly, linear relationships are confirmed between the mean and percentile wind speeds. These findings will help the understanding of the unsteadiness nature of turbulent flow in urban boundary layer especially when evaluating very rare events such as gusts or extreme low winds..
150. Naoki Ikegaya, Chiyoko Hirose, Aya Hagishima, Jun Tanimoto, Effect of turbulent flows generated by simplified roughness blocks on instantaneous wall pressure based on large-eddy simulation, Journal of Wind Engineering, 10.5359/jwe.42.22, 42, 1, 22-35, 2017.01, We have performed Large-Eddy Simulation of flow and pressure fields over two types of urban-like block arrays in order to investigate the relationships between instantaneous building wall pressure and surrounding flow fields. The adopted block arrays are: lattice-type square and staggered pattern. The analysis on the distributions of statistics for wall pressure shows that the large values of the statistics are observed along with the top and side edges of the wall for the square array, whereas they are shown on an upper half region of the wall for the staggered array. These large values are due to air flow introduction from both above and side of the target block for square array; in contrast, strong flows introduced into canopy area cause large pressures of the upper half of the wall for staggered array..
151. Naoki Ikegaya, Y. Ikeda, Aya Hagishima, A. A. Razak, Jun Tanimoto, A prediction model for wind speed ratios at pedestrian level with simplified urban canopies, Theorectical and Applied Climatology, 10.1007/s00704-015-1655-z, 127, 3-4, 655-665, 2017.02, The purpose of this study is to review and improve prediction models for wind speed ratios at pedestrian level with simplified urban canopies. We adopted an extensive database of velocity fields under various conditions for arrays consisting of cubes, slender or flattened rectangles, and rectangles with varying roughness heights. Conclusions are summarized as follows: first, a new geometric parameter is introduced as a function of the plan area index and the aspect ratio so as to express the increase in virtual density that causes wind speed reduction. Second, the estimated wind speed ratios in the range 0.05 < z/h < 0.3, where h is the building height, are consistent with those derived from the database to within an error of ±25%. Lastly, the effects of the spatial distribution of the flow were investigated by classifying the regions near building models into areas in front of, to the side of, or behind the building. The correlation coefficients between the wind speeds averaged over the entire region, and the front or side region values are larger than 0.8. In contrast, in areas where the influence of roughness elements is significant, such as behind a building, the wind speeds are weakly correlated..
152. Jun Tanimoto, How does resolution of strategy affect network reciprocity in spatial prisoner's dilemma games?, Applied Mathematics and Computation, 10.1016/j.amc.2016.11.036, 301, 36-42, 2017.05, In the canonical framework of evolutionary 2�נ2 games, a binary strategy set comprising cooperation (C) and defection (D) has usually been presumed. Inspired by commonly observed real-world facts, we explore what happens if the resolution of strategy increases. As an extreme limit, the infinite resolution case is both a continuous and a mixed strategy defined by a real number in the range of [0,1]. We find that increasing resolution amplifies cooperation in spatial prisoner's dilemma games as compared with the binary strategy definition; however, this enhancement tendency with increasing resolution is not monotonic in the case of a mixed-strategy setting..
153. Tsuyoshi Sato, Aya Hagishima, Naoki Ikegaya, Jun Tanimoto, A study on accuracy of particle image velocimetry in a wind tunnel simulating airflow around building scale model, AIJ Journal of Technology and Design, 10.3130/aijt.23.567, 23, 54, 567-572, 2017.06, PIV is an attractive experimental method for investigating turbulent flow around building model in a wind tunnel. However, it is difficult to obtain data with high accuracy in large size wind tunnel. In this paper, first we give an overview of PIV technique and organize the experimental conditions of past PIV in urban climatology. Then, we consider a technological problem which is called peak locking. We explain the mechanism of the generation of peak locking and how it affects the final output. Avoiding peak locking is difficult in general experimental condition, but it is mitigated by a simple image processing..
154. Jun Tanimoto, Coevolution of discrete, mixed, and continuous strategy systems boosts in the spatial prisoner's dilemma and chicken games, Applied Mathematics and Computation, 10.1016/j.amc.2017.01.015, 304, 20-27, 2017.07, A coevolutionary model by which both the strategy system and strategy value itself are allowed to adapt is established in the framework of spatial 2 × 2 games. Agents decide to update their behaviors in accordance with a discrete strategy (with a binary strategy set comprising only either cooperation (C) or defection (D)), mixed strategy, or continuous strategy. Because of the evolutionary advantage of the mixed strategy, which allows relatively high cooperators to offer defection to their defective neighbors to avoid exploitation by them, we found that the mixed strategy diffuses to the entire society in most of the dilemma region, and uses robust cooperation to increase the agents’ typical payoffs..
155. Jun Tanimoto, Does information of how good or bad your neighbors are enhance cooperation in spatial Prisoner's games?, Chaos, Solitons and Fractals, 10.1016/j.chaos.2017.05.038, 103, 184-193, 2017.10, Network reciprocity is one of the key mechanisms to solve social dilemmas, and has attracted many researchers for the last decade. Here, we explore what happens if network reciprocity is dovetailed with indirect reciprocity. This is motivated by the idea that a player may utilize observed information to evaluate his neighbors. Simulations based on our minimal model reveal that adding indirect reciprocity does not always increase the level of cooperation beyond the level of model without indirect reciprocity. This implies that the combination of two different reciprocity mechanisms, each enhancing cooperation if applied independently, can lead negative interference effect on cooperation. The details of this depend on type of action assessment system determining what is good and bad. Interestingly, we found that a high level of information is not always superior to low levels of information..
156. Ryo Matsuzawa, Jun Tanimoto, Eriko Fukuda, Properties of a new small-world network with spatially biased random shortcuts, Physica A: Statistical Mechanics and its Applications, 10.1016/j.physa.2017.05.031, 486, 408-415, 2017.11, This paper introduces a small-world (SW) network with a power-law distance distribution that differs from conventional models in that it uses completely random shortcuts. By incorporating spatial constraints, we analyze the divergence of the proposed model from conventional models in terms of fundamental network properties such as clustering coefficient, average path length, and degree distribution. We find that when the spatial constraint more strongly prohibits a long shortcut, the clustering coefficient is improved and the average path length increases. We also analyze the spatial prisoner's dilemma (SPD) games played on our new SW network in order to understand its dynamical characteristics. Depending on the basis graph, i.e., whether it is a one-dimensional ring or a two-dimensional lattice, and the parameter controlling the prohibition of long-distance shortcuts, the emergent results can vastly differ..
157. Naoki Ikegaya, Y. Ikeda, Aya Hagishima, Jun Tanimoto, Evaluation of rare velocity at a pedestrian level due to turbulence in a neutrally stable shear flow over simplified urban arrays, Journal of Industrial Aerodynamics, 10.1016/j.jweia.2017.10.002, 171, 137-147, 2017.12, The geometric dependency of the wind environment at a pedestrian level is an important issue that influences human comfort and safety in urban outdoor spaces. As such, this paper proposes to investigate the statistical features of wind speeds at the pedestrian level by calculating wind speed probability density functions based on flow field data from large-eddy simulations of simplified urban arrays, aiming to clarify the effects of urban geometry on rare velocity events such as strong gusts or extremely weak air flow. Though strong wind events occur infrequently, a positive correlation was demonstrated between percentile and mean wind speeds, indicating that the risk of gusty events increases with the increase of mean wind speeds. Conversely, the frequency of weak wind events shows an inverse correlation with mean wind speeds, showing that better ventilated urban arrays will retain higher wind speeds. Furthermore, these percentiles and occurrence frequencies are clearly expressed by the frontal area indices of urban block arrays. These results imply a trade-off between the following two objectives for urban area wind environments characterized by the urban geometry: enhancing air ventilation in urban areas and preventing strong wind gust events at a pedestrian level..
158. Yuki Ida, Jun Tanimoto, Effect of noise-perturbing intermediate defense measures in voluntary vaccination games, Chaos, Solitons and Fractals, 10.1016/j.chaos.2017.11.031, 106, 337-341, 2018.01, Recently, a new vaccination game model was proposed, where an intermediate defense measure besides two fundamental strategies; committing vaccination that leads to a perfect immunity and not committing vaccination, was introduced as third strategy. We explore what happens if both effectiveness and cost of an intermediate defense measure stochastically perturbing on the viewpoint of whether or not the third strategy helping to improve total social payoff. We found that unlike resonance effect by adding noise to payoff matrix in case of spatial prisoner's dilemma (SPD) games, adding time-varying noise on both effectiveness and cost does not make difference from the default setting without perturbation to the third strategy. However, if the noise initially given to each agent is frozen, we found the third strategy becoming robust to survive. In particular, if the strategy updating rule allows a more advantageous third strategy can be more commonly shared among agents through copying, the total social payoff is significantly improved..
159. Yoshiro Iwamura, Jun Tanimoto, Realistic decision-making processes in a vaccination game, Physica A: Statistical Mechanics and its Applications, 10.1016/j.physa.2017.11.148, 494, 236-241, 2018.03, Previous studies of vaccination games have nearly always assumed a pairwise comparison between a focal and neighboring player for the strategy updating rule, which comes from numerous compiled studies on spatial versions of 2-player and 2-strategy (2 × 2) games such as the spatial prisoner's dilemma (SPD). We propose, in this study, new update rules because the human decision-making process of whether to commit to a vaccination is obviously influenced by a “sense of crisis” or “fear” urging him/her toward vaccination, otherwise they will likely be infected. The rule assumes that an agent evaluates whether getting a vaccination or trying to free ride should be attempted based on observations of whether neighboring non-vaccinators were able to successfully free ride during the previous time-step. Compared to the conventional updating rule (standard pairwise comparison assuming a Fermi function), the new rules generally realize higher vaccination coverage and smaller final epidemic sizes. One rule in particular shows very good performance with significantly smaller epidemic sizes despite comparable levels of vaccination coverage. This is because the specific update rule helps vaccinators spread widely in the domain, which effectively hampers the spread of epidemics..
160. 谷本潤, Coevolution of discrete, mixed, and continuous strategy systems boosts in the spatial prisoner's dilemma and chicken games, Applied Mathematics and Computation, http://dx.doi.org/10.1016/j.amc.2017.01.016, 304, 1, 20-27, 2017.01.
161. 谷本潤, How does resolution of strategy affect network reciprocity in spatial prisoner’s dilemma games?, Applied Mathematics and Computation, http://dx.doi.org/10.1016/j.amc.2016.11.036, 301, 15, 36-42, 2016.11.
162. Matsuzawa R, 谷本潤, A social dilemma structure in diffusible public goods, EPL, http://dx.doi.org/10.1209/0295-5075/116/38005, 116, 38005-38005, 2016.10.
163. Fukuda E, 谷本潤, Iwamura Y, Nakamura K, Akimoto M, Field measurement analysis to validate lane-changing behavior in a cellular automaton model, Physical Review E, http://link.aps.org/doi/10.1103/PhysRevE.94.052209, 94, 052209-052209, 2017.08.
164. Iwamura R, 谷本潤, Fukuda E, Effect of intermediate defense measures in voluntary vaccination games, Journal of Statistical Mechanics: Theory and Experiment, http://dx.doi.org/10.1088/1742-5468/2016/09/093501, 093501-093501, 2016.09.
165. Matsuzawa Ryou, 谷本潤, Fukuda Eriko, Spatial prisoner's dilemma games with zealous cooperators, Physical Review E, http://dx.doi.org/10.1103/PhysRevE.94.022114, 94, 022114-022114, 2016.06.
166. 谷本潤, A Enhancement of cooperation in the spatial prisoner's dilemma with a coherence-resonance effect through annealed randomness at a cooperator-defector boundary; comparison of two variant models, Physica A, http://dx.doi.org/10.1016/j.physa.2016.06.002, 462, 714-724, 2016.05.
167. 谷本潤, A multi-community homogeneous small-world network and its fundamental characteristics, Physica A, 2016.09.
168. 谷本潤, Nakamura,K., Social dilemma structure hidden behind traffic flow with route selection, Physica A, http://dx.doi.org/10.1016/j.physa.2016.04.023, 459, 92-99, 2016.08.
169. 谷本潤, 萩島 理, 池谷 直樹, Hirose,C., Effect of turbulent flow on wall pressure coefficients of block arrays within urban boundary layer, Building and Environment, 100, 28-39, 2016.03.
170. 谷本潤, 萩島 理, 池谷 直樹, Chung, J., Wind-tunnel study of scalar transfer phenomena for surfaces of block arrays and smooth walls with dry patches, Boundary-Layer Meteorology, 157, 219-236, 2015.11.
171. 谷本潤, Sagara, H., How the indirect reciprocity with co-evolving norm and strategy for 2 × 2 prisoner's dilemma game works for emerging cooperation, Physica A, 438, 595-602, 2016.01.
172. 谷本潤, Fukuda, E., Effects of stubborn decision-makers on vaccination and disease propagation in social networks, International Journal of Automation and Logistics, 2, 78-92, 2016.01.
173. Tanimoto, Jun, Satoshi Kokubo, Zheng Wang, Marco Jusup, Universal scaling for the dilemma strength in evolutionary games, Physics of Life Reviews, http://dx.doi.org/10.1016/j.plrev.2015.04.033, 2015.06, Why would natural selection favor the prevalence of cooperation within the groups of selfish individuals? A fruitful framework to address this question is evolutionary game theory, the essence of which is captured in the so-called social dilemmas. Such dilemmas have sparked the development of a variety of mathematical approaches to assess the conditions under which cooperation evolves. Furthermore, borrowing from statistical physics and network science, the research of the evolutionary game dynamics has been enriched with phenomena such as pattern formation, equilibrium selection, and self-organization. Numerous advances in understanding the evolution of cooperative behavior over the last few decades have recently been distilled into five reciprocity mechanisms: direct reciprocity, indirect reciprocity, kin selection, group selection, and network reciprocity. However, when social viscosity is introduced into a population via any of the reciprocity mechanisms, the existing scaling parameters for the dilemma strength do not yield a unique answer as to how the evolutionary dynamics should unfold. Motivated by this problem, we review the developments that led to the present state of affairs, highlight the accompanying pitfalls, and propose new universal scaling parameters for the dilemma strength. We prove universality by showing that the conditions for an ESS and the expressions for the internal equilibriums in an infinite, well-mixed population subjected to any of the five reciprocity mechanisms depend only on the new scaling parameters. A similar result is shown to hold for the fixation probability of the different strategies in a finite, well-mixed population. Furthermore, by means of numerical simulations, the same scaling parameters are shown to be effective even if the evolution of cooperation is considered on the spatial networks (with the exception of highly heterogeneous setups). We close the discussion by suggesting promising directions for future research including (i) how to handle the dilemma strength in the context of co-evolution and (ii) where to seek opportunities for applying the game theoretical approach with meaningful impact..
174. Tanimoto, Jun, Eriko Fukuda, Mitsuhiro Akimoto, Influence of breaking the symmetry between disease transmission and information propagation networks on stepwise decisions concerning vaccination, Chaos, Solitons & Fractals, http://dx.doi.org/10.1016/j.chaos.2015.04.018, 80, 47-55, 2015.06.
175. Tanimoto, Jun, Shinji Kukida, Aya Hagishima, Naoki Ikegaya, Traffic flow simulation dovetailed with evolutionary game theory, Proc. of 4th International Conference on Simulation and modeling Methodologies, Technologies and Applications, 2014.08.
176. Tanimoto, Jun, The impact of initial cooperation fraction on the evolutionary fate in a spatial prisoner's dilemma game, Applied Mathematics and Computation, 2015.06.
177. Satoshi Kokubo, Zhen Wang, Tanimoto, Jun, Spatial reciprocity for discrete, continuous and mixed strategy setups, Applied Mathematics and Computation , http://dx.doi.org/10.1016/j.amc.2015.03.018, 259, 562-568, 2015.05.
178. Tanimoto, Jun, Correlated asynchronous behavior updating with a mixed strategy system in spatial prisoner's dilemma games enhances cooperation, Chaos, Solitons & Fractals, http://dx.doi.org/10.1016/j.chaos.2015.03.021, 80, 39-46, 2015.05.
179. Tanimoto, Jun, Nobuyuki Kishimoto, Network reciprocity created in prisoner’s dilemma games by coupling two mechanisms, Physical Review E, http://dx.doi.org/10.1103/PhysRevE.91.042106, 91, 042106-042106, 2015.04.
180. Tanimoto, Jun, Network reciprocity created in prisoner’s dilemma games by coupling two mechanisms, Physical Review E , 2015.05.
181. Tanimoto, Jun, Considering individual satisfaction levels enhances cooperation in a spatial prisoner's dilemma game, Chaos, Solitons & Fractals, http://dx.doi.org/10.1016/j.chaos.2015.02.025, 80, 24-30, 2015.04.
182. Tanimoto, Jun, Ogasawara, Takashi, Dynamic noise from action errors enhances network reciprocity in the prisoner’s dilemma game, Journal of Statistical Mechanics: Theory and Experiment, http://dx.doi.org/10.1088/1742-5468/2015/01/P01033, P1033, 2015.01.
183. Ogasawara, Takashi, Tanimoto, Jun, Fukuda, Eriko, Aya Hagishima, Naoki Ikegaya, Large strategy adaptation neighborhood bolsters network reciprocity in prisoner's dilemma, Proc. of 18th Asia Pacific System on Intelligent and Evolutionary System, CD-ROM, 2014.11.
184. Fukuda, Eriko, Tanimoto, Jun, Impact of stubborn individuals on spread of infectious disease under voluntary vaccination policy, Proc. of 18th Asia Pacific System on Intelligent and Evolutionary System, CD-ROM, 2014.11.
185. Tanimoto, Jun, Ogasawara, Takashi, Fukuda, Eriko, Aya Hagishima, Naoki Ikegaya, Effect of a large gaming neighborhood and a strategy adaptation neighborhood for bolstering network reciprocity in a prisoner's dilemma game, Journal of Statistical Mechanics: Theory and Experiment, http://iopscience.iop.org/1742-5468/2014/12/P12024/, P12024, 2014.12.
186. Tanimoto, Jun, Fujiki, Takuya, Kukida, Shinji, Naoki Ikegaya, Aya Hagishima, Acquisition of the field measurement data relating to lane change actions, International Journal of Modern Physics C, http://dx.doi.org/10.1142/S0129183115500722, 26, 1550072-1550072, 2015.04.
187. Tanimoto, Jun, Fujiki, Takuya, Wang, Zhen, Aya Hagishima, Naoki Ikegaya, Dangerous drivers foster social dilemma structures hidden behind a traffic flow with lane changes, Journal of Statistical Mechanics: Theory and Experiment, http://dx.doi.org/10.1088/1742-5468/2014/11/P11027, P11027, 2014.11.
188. Tanimoto, Jun, Dynamics of spatial traveler’s dilemma games, Journal of Statistical Mechanics: Theory and Experiment, http://iopscience.iop.org/1742-5468/2014/11/P11010/, P11010, 2014.11.
189. Tanimoto, Jun, Impact of deterministic and stochastic updates on network reciprocity in prisoner's dilemma game, Physical Review E, http://link.aps.org/doi/10.1103/PhysRevE.90.022105, 90, 022105, 2014.08.
190. Fukuda, Eriko, Kokubo, Satoshi, Tanimoto, Jun, Wang, Zhen, Aya Hagishima, Naoki Ikegaya, Risk assessment for infectious disease and its impact on voluntary vaccination behavior in social networks, Chaos, Solitons & Fractals, http://dx.doi.org/10.1016/j.chaos.2014.07.004, 68, 1-9, 2014.10.
191. Tanimoto, Jun, Kukida, Shinji, Aya Hagishima, Social dilemma structures hidden behind a traffic flow with lane changes, Journal of Statistical Mechanics: Theory and Experiment, http://dx.doi.org/ 10.1088/1742-5468/2014/07/P07019, P07019, 2014.08.
192. 谷本潤, Kukida Shinji, 池谷直樹, 萩島理, Analytical solutions of Fukui-Ishibashi (FI) model and Quick-Start (QS) model, Journal of Applied Mathematics and Physics, http://dx.doi.org/10.4236/jamp.2014.27076, 2, 7, 691-697, 2014.08.
193. Tanimoto, Jun, Assortative and dissortative priorities for game interaction and strategy adaptation significantly bolster network reciprocity in the prisoner's dilemma, Journal of Statistical Mechanics: Theory and Experiment, doi:10.1088/1742-5468/2014/05/P05003, P05003, 2014.04.
194. Miyaji, Kohei, Tanimoto、Jun, Hagishima, Aya, Ikegaya, Naoki, Influence of stochastic perturbation of both action updating and strategy updating in mixed-strategy 2 times 2 games on evolution of cooperation, Physical Review E, http://link.aps.org/doi/10.1103/PhysRevE.88.062149, 88, 062149, 2013.12, [URL].
195. Tanimoto、Jun, Simultaneously selecting appropriate partners for gaming and strategy adaptation to enhance network reciprocity in the prisoner's dilemma, Physical Review E, http://dx.doi.org/10.1103/PhysRevE.89.012106, 89, 012106, 2014.01, [URL].
196. Wang, Zhen, Kokubo, Satoshi, Tanimoto、Jun, Fukuda, Eriko, Shigaki, Keizo, Insight on the so-called spatial reciprocity, Physical Review E, http://dx.doi.org/10.1103/PhysRevE.88.042145, 88, 042145, 2013.10, [URL].
197. Tanimoto、Jun, Shigaki, Keizo, Wang, Zhen, Fukuda, Eriko, Effect of initial fraction of cooperators on cooperative behavior in evolutionary prisoner's dilemma, PLOS One, http://dx.doi.org/10.1371/journal.pone.0076942, 8, 11, e76942, 2013.11, [URL].
198. Hagishima, Aya, Tanimoto, Jun, Ikegaya, Naoki, Mitsuyasu, Seijirou, Stochastic characteristics of thermal load in a single dwelling in a residential building based on building energy simulation coupled with a sub-model for considering variation on behavior schedules of residents, Proc. of 13th Building Simulation 2013, 2013.08.
199. Mohamad Mohd Faizal1, Hagishima, Aya, Ikegaya, Naoki, Tanimoto, Jun, Wind-induced natural ventilation in typical single story terraced houses in Malaysia, Proc. of 13th Building Simulation 2013, 2013.08.
200. Kishimoto, Noriyuki, Kokubo, Satoshi, Tanimoto, Jun, Combination of continuous and binary strategies enhances network reciprocity in a spatial prisoner's dilemma game, Chaos, Solitons & Fractals, http://dx.doi.org/10.1016/j.chaos.2013.07.00, 56, 83-90, 2013.11, [URL].
201. Miyaji, Kohei, Wang, Zhen, Tanimoto, Jun, Hagishima, Aya, Ikegaya, Naoki, Direct reciprocity in spatial populations enhances R-reciprocity as well as ST-Reciprocity, PLOS One, http://dx.doi.org/10.1371/journal.pone.0071961, 8, 8, e71961, 2013.08, [URL].
202. Tanimoto, Jun, Difference of reciprocity effect in two coevolutionary models of presumed two-player and multi-player games, Physical Review E, http://link.aps.org/doi/10.1103/PhysRevE.87.062136, 87, 6, 062136, 2013.06, [URL].
203. Sato, Tsuyoshi, Hagishima, Aya, Ikegaya, Naoki, Tanimoto, Jun, Particle image velocimetry measurement of unsteady turbulent flow around regularly arranged high-rise building models, International Journal of High-Rise Buildings, 2, 2, 105-113, 2013.06.
204. Miyaji, Kohei, Tanimoto, Jun, Wang, Zhen, Hagishima, Aya, Kokubo, Satoshi, The evolution of fairness in the coevolutionary ultimatum games, Chaos, Solitons & Fractals, http://dx.doi.org/10.1016/j.chaos.2013.05.007, 56, 13-18, 2013.11, [URL].
205. Tanimoto, Jun, Co-evolutionary, coexisting learning and teaching agents model for prisoner's dilemma games enhancing cooperation with assortative heterogeneous networks, Physica A, http://dx.doi.org/10.1016/j.physa.2013.02.004, 392, 13, 2955-2964, 2013.07.
206. Nik Ibrahim,I., Ikegaya,N., Hagishima,A., Tanimoto,J., A study on the similarity between scalar and momentum roughness lengths based on the scalar concentration measurement, Proc. of 1st Asia Conference of International Building Performance Simulation Association (ASim2012), 2012.11.
207. Kishimoto,N., Kokubo,S., Tanimoto,J., Network reciprocity on spatial prisoner’s dilemma games by continuous-binary strategy, Proc. of 6th International Conference on Soft Computing and Intelligent Systems, and 13th International Symposium on Advanced Intelligent Systems (SCIS-ISIS 2012), 2012.11.
208. Shigaki,K., Tanimoto,J., Wang,Z., Hagishima,A, Ikegaya,N, A new Pairwise Fermi update rule, not referring to randomly selected opponent's payoff but social average payoff of same strategy the opponent has, significantly enhances cooperation in spatial prisoner's dilemma games, Physical Review E, http://link.aps.org/doi/10.1103/PhysRevE.86.031141, 86, 031141, 2012.11.
209. Tanimoto,J., Hagishima,A., Iwai,T., Ikegaya,N., Total utility demand prediction for multi-dwelling sites by a bottom-up approach considering variations of inhabitants’ behavior schedules, Journal of Building Performance Simulation, 2012.04.
210. Tanimoto,J., Brede,M., Yamauchi,A., Network reciprocity by coexisting learning and teaching strategies, Physical Review E, 85, 2012.08.
211. Park,M., Hagishima,A., Tanimoto,J., Effect of urban vegetation on outdoor thermal environment filed measurement at a scale model site, Building and Environment, 2012.08.
212. Sheikh,A.Z., Hagishima,A., Tanimoto,J., Experimental study of wind-induced ventilation in urban building of cube arrays with various layouts, Journal of Wind Engineering & Industrial Aerodynamics , http://dx.doi.org/10.1016/j.jweia.2012.02.008, 103, 31-40, 2012., 2012.01.
213. Ikegaya,N., Hagishima,A., Tanimoto,J., Tanaka,Y., Narita,K. Sheikh Ahmad,Z., Geometric Dependence of the Scalar Transfer Efficiency over Rough Surfaces, Boundary-Layer Metrology , 142 (2),, 2012.01.
214. Zhong,W., Kokubo,S., Tanimoto,J., How is the equilibrium of continuous strategy game different from that of discrete strategy game?, BioSystems , http://dx.doi.org/10.1016/j.biosystems.2011.10.001, 107 (2), 89-94, 2012.01.
215. Shigaki,K., Tanimoto.J., Hagishima,A., A Revised Stochastic Optimal Velocity Model Considering the Velocity Gap with a Preceding Vehicle, Journal of Modern Physics C, http://dx.doi.org/10.1142/S0129183111016749, 22 (9), 1005-1014, 2011.10.
216. Tanimoto,J., Hagishima,A, Iwai,T., Ikegaya,N., Total utility demand prediction for multi-dwelling sites considering variation of occupant behavior schedules, Proc. of 12th IBPSA Conference, 2011.11.
217. Zaki,S,A., Hagishima,A., Tanimoto,J., Spatial distribution of pressure drag acting on rectangular block arrays with various layouts, Proc. of 12th IBPSA Conference, 2011.11.
218. Tanimoto,J., Nakata,M., Hagishima,A., Ikegaya,N., Spatially correlated heterogeneous aspirations to enhance network reciprocity, Physica A, 2011.11.
219. Shigaki,K., Tanimoto.A., Hagishima,A., A Revised Stochastic Optimal Velocity Model Considering the Velocity Gap with a Preceding Vehicle, International Journal of Modern Physics C, 2011.09.
220. Tanimoto,J., Influence of strategy adaptation speed on network reciprocity for evolutionary prisoner’s dilemma games, Sociobiology, 58, 2, 315-325, 2011.11.
221. Tanimoto,J., Sagara,H., Social diffusive impact analysis based on evolutionary computations for a novel car navigation system sharing individual information in urban traffic systems, Journal of Navigation, 64, 4, 1-15, 64 (4), 1-15 , 2011, 2011.10.
222. Tanimoto,J., A study of a quadruple co-evolutionary model and its reciprocity phase for various Prisoner’s Dilemma games, International Journal of Modern Physics C, 2011.09.
223. Kukida,S., Tanimoto,J., Hagishima,A., Analysis of the influence of lane changing on traffic-flow dynamics based on the cellular automaton model, International Journal of Modern Physics C, 22, 3, 271-281, 2011.04.
224. Tanimoto,J., Hagishima,A., State Transition Stochastic Model for Predicting Off-to-On Cooling Schedule in Dwellings as Implemented using a Multilayered Artificial Neural Network, Journal of Building Performance Simulation, Journal of Building Performance Simulation, 2011.12, Our previous study (Tanimoto & Hagishima (2005), Energy and Buildings) proposed a set of state transition probabilities for the Markov chain dealing with the on/off cooling schedule in dwellings. The probability of turning on an air conditioner was defined in the form of a sigmoid function by the indoor globe temperature. Obviously, a real stochastic event of shifting from the off to on state is affected by not only indoor thermal quality parameters but also other complex factors such as the presence of family members, time of the day, and whether it is a weekday or holiday. In this paper, we report an alternate model, based on a multilayered artificial neural network (MANN), for predicting the off to on cooling schedule. We gathered field measurement data on family dwellings during the summer of 2008 by deploying hygrothermometers with recording functions to measure the room temperature and the globe and blowout air temperature of the air conditioner. The MANN used has nine nodes in both its input and hidden layers and a single node in its output layer, which implies that the state is either shifting from off to on (1) or not (0). The information provided to the input layer nodes includes the time of the day, whether it is a weekday or holiday, the probability of the presence of inhabitants, and the predicted percentage of dissatisfied people (PPD). PPD, derived from PMV theory, is applied as a representative parameter of the indoor thermal quality, in place of the globe temperature, since it accounts for various influences. The field measurement datasets were divided into two parts: teaching data and data for validation. A model trained by the teaching data was confirmed to reproduce the state transition characteristic of the validation period, which seems complex and is determined by the behavior of various inhabitants. The performance of the model in reproducing this behavior is improved over that of the previous model derived from the Markov chain..
225. Wakiyama,M., Tanimoto,J., Reciprocity phase in various 2×2 games by agents equipped with 2-memory length strategy encouraged by grouping for interaction and adaptation, BioSystems, http://dx.doi.org/10.1016/j.biosystems.2010.10.009, 103, 93-104, 2010.10.
226. Kokubo,S., Tanimoto,J., Hagishima,A., A new Cellular Automata Model including a decelerating damping effect to reproduce Kerner’s three-phase theory, Phyisica A, http://dx.doi.org/10.1016/j.physa.2010.10.027, 390, 4, 561-568, 2010.10.
227. Zaki,S,A., Hagishima,A., Tanimoto,J., Ikegaya,N., Aerodynamic parameters of urban building arrays with random geometries, Boundary-Layer Meteorology, http://www.springerlink.com/openurl.asp?genre=article&id=doi:10.1007/s10546-010-9551-7., 138 , 1, 99-12, 2010.11.
228. Yamauchi,A., Tanimoto,J., Hagishima,A., An analysis of network reciprocity in Prisoner’s Dilemma games using Full Factorial Designs of Experiment, BioSystems, http://dx.doi.org/10.1016/j.biosystems.2010.10.006, 103, 85-92, 2010.10.
229. Tanimoto,J., Hagishima,A., Tanaka,Y., Study of bottleneck effect at an emergency evacuation exit using cellular automata model, Physica A , http://dx.doi.org/10.1016/j.physa.2010.08.032, 389 , 24, 5611-5618, 2010.08.
230. Nakata,M., Yamauchi,A., Tanimoto,J., Hagishima,A., Dilemma game structure hidden in traffic flow at a bottleneck due to a 2 into 1 lane junction, Physica A, http://dx.doi.org/10.1016/j.physa.2010.08.005, 389, 5353-5361, 2010.08.
231. Yamauchi,A, Tanimoto,J., Hagishima,A., What controls network reciprocity in the prisoner’s dilemma game?, BioSystems, http://dx.doi.org/10.1016/j.biosystems.2010.07.017, 102 , 2-3, 82-87, 2010.06.
232. Tanimoto,J., Editorial; Evolutionary World; Games, Complex networks, Agent simulations, International Journal of Bio-inspired Computation , 3, 3, 2011.09.
233. Tanimoto,J., Effect of assortativity by degree on emerging cooperation in a 2 x 2 dilemma game played on an evolutionary network, Physica A, http://dx.doi.org/10.1016/j.physa.2010.03.020, 2010.04, [URL].
234. , [URL].
235. Tanimoto,J., Hagishima,A, Total Utility Demand Prediction System for dwellings based on stochastic processes of actual inhabitants, Journal of Building Performance Simulation, 2010.04.
236. Jun Tanimoto, Atsuo Yamauchi, Game participation cost brakes the advantage of heterogeneous networks for evolving cooperation, Proc. of 13th Asia-Pacific Workshop on Intelligent Evolutionary Systems, 2009.12.
237. Atsuo Yamauchi, Jun Tanimoto, Aya Hagishima, Factorial analysis on network reciprocity in Prisoner’s Dilemma Game, Proc. of 13th Asia-Pacific Workshop on Intelligent Evolutionary Systems, 2009.12.
238. Makoto Nakata, Atsuo Yamauchi, Jun Tanimoto, Aya Hagishima, Dilemma game structure in traffic flow brought by a bottleneck, Proc. of 13th Asia-Pacific Workshop on Intelligent Evolutionary Systems, 2009.12.
239. Tanimoto,J., Hagishima,A;, Total utility demand prediction based on probabilistically generated behavioral schedules of actual inhabitants, 11th IBPSA Conference, 2009.08.
240. Aya Hagishima1 , Jun Tanimoto1, Koji Nagayama1 and Sho Meno1, Aerodynamic Parameters of Regular Arrays of Rectangular Blocks with Various Geometries, Boundary-Layer Meteorology, 132 , 315-337 , 2009., 2009.09.
241. Oliveira,J.T., Hagishima, A., Tanimoto,J., Estimation of passive cooling efficiency for environmental design in Brazil,, Energy and Buildings , 41, 809-813, 2009., 2009.07.
242. Yamauchi,A., Tanimoto,J., Hagishima,A. Sagara,H., Dilemma Game Structure Observed in Traffic Flow at a 2-to-1 Lane Junction, Physical Review E, 79 , #036104, 2009.05.
243. Tanimoto,J., Promotion of cooperation through co-evolution of networks and strategy in a 2 x 2 game, Physica A, 2009.03.
244. Tanimoto,J., A simple scaling of the effectiveness of supporting mutual cooperation in donor-recipient games by various reciprocity mechanisms, BioSystems, 2009.03.
245. Tanimoto,J., Co-evolution Model of Networks and Strategy in a 2 × 2 Game Emerges Cooperation, IEEE World Congress on Computational Intelligence, 117-122, 2008.06.
246. Hagishima, A., Tanimoto J., Wind tunnel experiment in drag force coefficient of urban-like roughness with height variation, Proc of AWAS 2008, 2008.06.
247. Tanimoto, J., Emergence of cooperation in patchy habitat with mortality and colonization based on various 2 x 2 games, Sociobiology , 52 (2), 185-206, 2008.05.
248. Hagishima. A., Narita. K., Tanimoto. J., Field experiment on transpiration from isolated urban plants, Hydrological Process , 21, 1217-1222, 2007.11, [URL].
249. Tanimoto, J., What initially brought about communications?, BioSystems, 92 (1) , 82-90, 2008.06, [URL].
250. Tanimoto,J., Hagishima,A., Sagara,H., Validation of Methodology for Utility Demand Prediction Considering Actual Variations in Inhabitant Behavior Schedules, Journal of Building Performance Simulation, 1 (1), 2008.04.
251. Sagara,H., Tanimoto,J., Analysis of Impact of Communication Among Different Norms in Norm Reputation Model, Proc. of 11th Asia-Pacific Workshop on Intelligent Evolutionary Systems, 2007.11.
252. Tanimoto,J., Promotion of cooperation by payoff noise in a 2 × 2 game, Physical Review E , 76, #041130, 2007.11, [URL].
253. Tanimoto,J., Dilemma-solving effects by the coevolution of both networks and strategy in a 2 x 2 game, Physical Review E, 2007.12.
254. Sagara,H., Tanimoto,J., A Study on Social Diffusive Impacts of a Novel Car-Navigation-System Sharing Individual Information in Urban Traffic Systems, IEEE Congress on Evolutionary Computation 2007, 2007.09.
255. Tanimoto,J., Emergence of Cooperation Supported by Communication in a One-Shot 2 x 2 Game, IEEE Congress on Evolutionary Computation 2007, 2007.09.
256. Tanimoto,J., Hagishima,A., Sagara,H., Validation of the Probabilistic Methodology to Generate Actual Inhabitants’ Behavior Schedules for Accurate Prediction of Maximum Energy Requirement, 10th IBPSA Conference, 2007.09.
257. (10) Jun Tanimoto, A study of indirect reciprocity involving a reputation system or a simple tag system in a one-shot, multi-player game, BioSystems, in Press, [URL].
258. Jun Tanimoto, Does a Tag System Effectively Support Emerging Cooperation?, Journal of Theoretical Biology, 247(4), 756-764, 2007.09, [URL].
259. Jun Tanimoto, A study on emergence of Coordinated Alternating Reciprocity in a 2x2 game with 2-memory length strategy, BioSystems, 2007.09, [URL].
260. Jun Tanimoto, Aya Hagishima, Hiroki Sagara, Validation of Probabilistic Methodology for Generating Actual Inhabitants' Behavior Schedules for Accurate Prediction of Maximum Energy Requirements, Energy and buildings, 43, 610-619, 2007.09, [URL].
261. Jun Tanimoto, Aya Hagishima, Hiroki Sagara, A methodology for peak energy requirement considering actual variation of occupants’ behavior schedules, Building and Environment, 43 (4), 610-619, 2007.09, [URL].
262. Jun Tanimoto, Differences in Dynamics between Discrete Strategies and Continuous Strategies in a Multi-player Game with a Linear Payoff Structure, BioSystems, 90(2), 568-572, 2007.10, [URL].
263. Jun Tanimoto, Hiroki Sagara, Relationship between dilemma occurrence and the existence of a weakly dominant strategy in a two-player symmetric game, BioSystems, 90(1), 105-114, 2007.06, [URL].
264. Jun Tanimoto, Haruyuki Fujii, A model for Collusive tendering based on a multiagent approach, Agent-Based Modering Meets Gameing Simulation, Springer-Verlag, 2005, pp.89-100, 2005.12.
265. Jun Tanimoto, Aya Hagishima, Cooling Load Simulation Considering Actual Variation of Inhabitants’ Behavior for Accurate Estimation of Urban Maximum Energy Requirement, 9th IBPSA Conference (Building Simulation 2005), 2005.12.
266. Hagishima. A.; Tanimoto.J.; Narita.K, Intercomparisons of experimental research on convective heat transfer coefficient of urban surfaces, Boundary-Layer Meteorology, 10.1007/s10546-005-2078-7, 117, 3, 551-576, 117, 551-576, 2005.01.
267. Jun Tanimoto and Aya Hagishima, State transition probability forthe Markov Model dealing with on/off cooling schedule in dwellings, Energy and Buildings, 10.1016/j.enbuild.2004.02.002, 37, 3, 181-187, Vol.37 No.3,pp.181-187, 2005.03.
268. Jun Tanimoto, Environmental dilemma game to establish a sustainable society dealing with an emergent value system, Physica D, 10.1016/j.physd.2004.09.016, 200, 1-2, 1-24, Vol. 200, pp.1-24, 2005.01.
269. P.Chimklai, A.Hagishima,J.Tanimoto, A computer system to support Albedo Calculation in urban areas, Building and Environment,, 10.1016/j.buildenv.2004.02.006, 39, 10, 1213-1221, Vol.39(10),pp1213-1221, 2004.10.
270. H. Fujii, J. Tanimoto, Integration of building simulation and agent simulation for exploration to environmentally symbiotic architecture?, Building and Environment, 10.1016/j.buildenv.2004.01.013, 39, 8, 885-893, vol 39,pp885-893, 2004.08.
271. J.Tanimoto; A.Hagishima; P.Chimklai,, An approach for coupled simulation of building thermal effects and urban climatology, Energy and Buildings, 10.1016/j.enbuild.2004.01.019, 36, 8, 781-793, vol 36,pp781-793, 2004.08.
272. J.Tanimoto, H. Fujii,, A Multi-Agent Simulation of a Dilemma Game to Establish a Sustainable Society Dealing with an Emergent Value System, 9th Workshop on Economics and Heterogeneous Interacting Agents(WEHIA), CD-ROM, 2004.05.