Kyushu University Academic Staff Educational and Research Activities Database
List of Papers
Arakawa Yutaka Last modified date:2021.05.18

Professor / Advanced Information and Communication Technology / Department of Advanced Information Technology / Faculty of Information Science and Electrical Engineering


Papers
1. Teruhiro Mizumoto, Yasuhiro Otoda, Chihiro Nakajima, Mitsuhiro Kohana, Motohiro Uenishi, Keiichi Yasumoto, Yutaka Arakawa, Design and implementation of sensor-embedded chair for continuous sitting posture recognition, IEICE Transactions on Information and Systems, 10.1587/transinf.2019EDP7226, E103D, 5, 1067-1077, 2020.05, In this paper, we design and develop a sensor-embedded office chair that can measure the posture of the office worker continuously without disturbing their job. In our system, eight accelerometers, that are attached at the back side of the fabric surface of the chair, are used for recognizing the posture. We propose three sitting posture recognition algorithms by considering the initial position of the chair and the difference of physique. Through the experiment with 28 participants, we confirm that our proposed chair can recognize the sitting posture by 75.4% (algorithm 1), 83.7% (algorithm 2), and 85.6% (algorithm 3) respectively..
2. Manato Fujimoto, Seigi Matsumoto, Edgar Marko Trono, Yutaka Arakawa, Keiichi Yasumoto, Effective application distribution system for internet-less communication during disasters, Sensors and Materials, 10.18494/SAM.2020.2614, 32, 1, 79-95, 2020.01, Smartphone-based disaster communication systems have been the topic of many recent studies. However, existing systems unrealistically assume that prior to a disaster, the required applications have been installed in the smartphones of all users. In disaster areas without Internet access, obtaining the software required for communications systems is difficult because application distribution platforms, such as Google Play, are web-based. In this paper, we present RecurShare, which is a novel application distribution system. The key idea of RecurShare is to be able to distribute applications without the Internet by running a web server that can be accessed using the default web browser and the tethering function of Android smartphones. We evaluated the feasibility of RecurShare experimentally and showed that RecurShare functions without problems on a variety of commercial devices. Also, user feedback suggests that RecurShare sufficiently guides users through the application distribution process in a manner that is easy to understand. Furthermore, we found that RecurShare can distribute itself at an exponential rate and that it can transmit files at speeds that are comparable to those of commonly used wireless communication systems..
3. Shigemi Ishida, Yutaka Arakawa, Shigeaki Tagashira, Akira Fukuda, Wireless Local Area Network Signal Strength Measurement for Sensor Localization without New Anchors, Sensors and Materials, 10.18494/SAM.2020.2592, 32, 1, 97, 2020.01, In sensor networks, sensor localization is one of the mandatory functions for physical sensing. In this paper, we propose a sensor localization system that utilizes wireless local area network (WLAN) access points (APs) as anchor nodes. WLAN is widely available nowadays, and WLAN APs are used in many environments. Therefore, for our localization system, we utilize the WLAN APs already installed in the environment, thereby eliminating the installation of new anchors. We present an AP received signal strength (RSS) measurement method, which is the key technology of our sensor localization system. Notably, sensor nodes equipped with an IEEE 802.15.4 (ZigBee) module cannot detect WLAN AP signals. We therefore developed an AP signal detection method with AP identification by employing a cross-technology signal detection technique. Experimental evaluations demonstrate that our AP signal detection method successfully identified sender APs with a false positive (FP) detection rate less than 20%. The experiments also validated that the measured AP-RSS followed the same distribution as the RSS measured using a WLAN device..
4. Shigemi Ishida, Yutaka Arakawa, Shigeaki Tagashira, Akira Fukuda, Wireless local area network signal strength measurement for sensor localization without new anchors, Sensors and Materials, 10.18494/SAM.2020.2592, 32, 1, 97-114, 2020.01, In sensor networks, sensor localization is one of the mandatory functions for physical sensing. In this paper, we propose a sensor localization system that utilizes wireless local area network (WLAN) access points (APs) as anchor nodes. WLAN is widely available nowadays, and WLAN APs are used in many environments. Therefore, for our localization system, we utilize the WLAN APs already installed in the environment, thereby eliminating the installation of new anchors. We present an AP received signal strength (RSS) measurement method, which is the key technology of our sensor localization system. Notably, sensor nodes equipped with an IEEE 802.15.4 (ZigBee) module cannot detect WLAN AP signals. We therefore developed an AP signal detection method with AP identification by employing a cross-technology signal detection technique. Experimental evaluations demonstrate that our AP signal detection method successfully identified sender APs with a false positive (FP) detection rate less than 20%. The experiments also validated that the measured AP-RSS followed the same distribution as the RSS measured using a WLAN device..
5. Yugo Nakamura, Yuki Matsuda, Yutaka Arakawa, Keiichi Yasumoto, Waistonbelt x
A belt-type wearable device with sensing and intervention toward health behavior change, Sensors (Switzerland), 10.3390/s19204600, 19, 20, 2019.10, Changing behavior related to improper lifestyle habits has attracted attention as a solution to prevent lifestyle diseases, such as diabetes, heart disease, arteriosclerosis, and stroke. To drive health behavior changes, wearable devices are needed, and they must not only provide accurate sensing and visualization functions but also effective intervention functions. In this paper, we propose a health support system, WaistonBelt X, that consists of a belt-type wearable device with sensing and intervention functions and a smartphone application. WaistonBelt X can automatically measure a waistline with a magnetometer that detects the movements of a blade installed in the buckle, and monitor the basic activities of daily living with inertial sensors. Furthermore, WaistonBelt X intervenes with the user to correct lifestyle habits by using a built-in vibrator. Through evaluation experiments, we confirmed that our proposed device achieves measurement of the circumference on the belt position (mean absolute error of 0.93 cm) and basic activity recognition (F1 score of 0.95) with high accuracy. In addition, we confirmed that the intervention via belt vibration effectively improves the sitting posture of the user..
6. Yuki Kanaya, Shogo Kawanaka, Hirohiko Suwa, Yutaka Arakawa, Keiichi Yasumoto, Automatic Tour Video Summarization Focusing on Scene Change for Advance Touristic Experience, 2nd International Conference on Multimedia Information Processing and Retrieval, MIPR 2019 Proceedings - 2nd International Conference on Multimedia Information Processing and Retrieval, MIPR 2019, 10.1109/MIPR.2019.00079, 391-392, 2019.04, In this paper, we propose a novel time-lapse based video summarization method without substantial loss of information important for viewers to plan a tour route. In the proposed method, we focus on scene changes in the video. We extract scenes with a certain level of changes compared to previous scenes as important (slowly played back) in the summarized video, while other scenes are fast forwarded. To evaluate the effectiveness of our proposed method, comparing the video summarized with our method and that summarized manually (by voting for necessary/unnecessary scenes), our method identified the important scenes with an F-measure of 62.22%..
7. Akira Fukuda, Tsuneo Nakanishi, Hisazumi Kenji, Kunihiko Kaneko, Shigeaki Tagashira, Tsunenori Mine, Yutaka Arakawa, Shigemi Ishida, Takahiro Ando, Shuichi Ashihara, Masakatsu Ura, Yoshimichi Nakamura, Soichiro Nakamura, Weiqiang Kong, Guoqiang Li, Toward Sustainable Smart Mobility Information Infrastructure Platform - Current Status - Current S, 7th International Congress on Advanced Applied Informatics, IIAI-AAI 2018 Proceedings - 2018 7th International Congress on Advanced Applied Informatics, IIAI-AAI 2018, 10.1109/IIAI-AAI.2018.00025, 81-85, 2019.04, Smart mobility systems, which include Intelligent Transportation Systems(ITS) and smart energy systems, become more important. There is, however, lack of its platform studies. We started a sustainable information infrastructure project for smart mobility systems. The project pursues issues that establish an information infrastructure architecture and seamless development method chain for it. The project has mainly two features; 1) applying life-cycle-oriented methods, which are a cycle from system development to operations, to a real world, and 2) dealing with an uncertainty in system design phase. This paper describes current status of the project..
8. Yutaka Arakawa, Mani Srivastava, PerPersuasion'19 - 1st International Workshop on Pervasive Persuasive System for Behavior Change - Welcome and Committees, 2019 IEEE International Conference on Pervasive Computing and Communications Workshops, PerCom Workshops 2019 2019 IEEE International Conference on Pervasive Computing and Communications Workshops, PerCom Workshops 2019, 10.1109/PERCOMW.2019.8730659, 2019.03.
9. Zhihua Zhang, Yuta Takahashi, Manato Fujimoto, Yutaka Arakawa, Keiichi Yasumoto, Investigating User Reactions to Interactive-signage-based Stimulation Toward Behavior Change, 11th International Conference on Mobile Computing and Ubiquitous Network, ICMU 2018 2018 11th International Conference on Mobile Computing and Ubiquitous Network, ICMU 2018, 10.23919/ICMU.2018.8653587, 2019.02, In recent years, many research and developments of behavior change have been conducted. The purpose of behavior change is to improve people's lifestyle pattern or to maintain the improvement for a long time aiming to achieve a goal of promoting health condition improvement. In order to achieve the foundation of a new lifestyle, it is necessary to recognize the daily life patterns of users and give triggers to users in their daily life for behavior change. To realize this, in this study, we construct an interactive signage which is able to positively talk to the passing user and try to induce behavior change by sending visual stimulation and auditory stimulation. In this paper, we report the result of the investigation on users' reactions and feelings to the proposed interactive signage. As a survey experiment, we set up 4 interactive signage on a floor of our university and asked 15 participants to carry a name tag with a BLE beacon during their daily life. There are 4 different dialogue scenarios and a scenario is posted to the participants when he/she approaches the interactive signage. Participants can respond to these scenarios through a touchscreen. Based on the result of the experiment, it is found that the interactive signage can induce behavior change effectively..
10. Yugo Nakamura, Teruhiro Mizumoto, Hirohiko Suwa, Yutaka Arakawa, Hirozumi Yamaguchi, Keiichi Yasumoto, Design and Evaluation of In-Situ Resource Provisioning Method for Regional IoT Services, 26th IEEE/ACM International Symposium on Quality of Service, IWQoS 2018 2018 IEEE/ACM 26th International Symposium on Quality of Service, IWQoS 2018, 10.1109/IWQoS.2018.8624127, 2019.01, In an era where billions of IoT devices are deployed, edge/fog computing paradigms are attracting attention for their ability to reduce processing delays and mitigate waste of communication resources. However, since the computing system assumed by edge/fog paradigms have heterogeneity (in terms of the computing power of devices, network performance between devices, device density, etc.), provisioning computational resources according to computational demand becomes a challenging constrained optimization problem. In this paper, we propose in-situ resource provisioning method consisting of insitu resource area selection with adaptive scale out and in-situ task scheduling based on tabu search algorithm. We conducted a simulation study in a target regional area where 2,000 IoT devices and 10 IoT services are deployed to evaluate the effectiveness of the proposed algorithm. The simulation results show that our proposed algorithm can obtain higher user QoS compared to conventional resource provisioning algorithms..
11. A. H.Elder Akpa, Masashi Fujiwara, Hirohiko Suwa, Yutaka Arakawa, Keiichi Yasumoto, A smart glove to track fitness exercises by reading hand palm, Journal of Sensors, 10.1155/2019/9320145, 2019, 2019.01, Medical studies have intensively demonstrated that sports activity can enhance both the mental and the physical health of practitioners. In recent years, fitness activity became the most common way to motivate and engage people in sports activity. Recently, there have been multiple attempts to elaborate on the “ideal” IoT-based solution to track and assess these fitness activities. Most fitness activities (except aerobic activities like running) involve one or multiple interactions between the athlete's hand palms and body or between the hand palms and the workout materials. In this work, we present our idea to exploit these biomechanical interactions of the hand palms to track fitness activities via a smart glove. Our smart glove-based system integrates force-sensitive resistor (FSR) sensors into wearable fitness gloves to identify and count fitness activity, by analyzing the time series of the pressure distribution in the hand palms observed during fitness sessions. To assess the performance of our proposed system, we conducted an experimental study with 10 participants over 10 common fitness activities. For the user-dependent activity recognition case, the experimental results showed 88.90% of the F score for overall activity recognition. The result of leave-one-participant-out cross-validation showed an F score ranging from 58.30% to 100%, with an average of 82.00%. For the exercise repetition count, the system achieved an average counting error of 9.85%, with a standard deviation of 1.38..
12. Zhihua Zhang, Yuta Takahashi, Manato Fujimoto, Yutaka Arakawa, Keiichi Yasumoto, Investigating effects of interactive signage–based stimulation for promoting behavior change, Computational Intelligence, 10.1111/coin.12234, 35, 3, 643-668, 2019.01, In recent years, many types of research and developments on behavior change have been conducted. The purpose of behavior change is to improve people's lifestyle pattern or to maintain the improvement for a long time with the aim to achieve a goal such as promoting health condition improvement. To achieve the foundation of a new lifestyle, it is necessary to recognize the daily life patterns of users and give triggers for behavior change to users in their daily life. To realize this, in our research, we develop an interactive signage which is able to identify and actively talk to the passing user and try to induce behavior change by sending visual and auditory stimulation. Then, we record users' reactions and upload them to the server. In this paper, we report the investigation result on users' reactions and feelings to the developed interactive signage. As a survey experiment, we set up four interactive signs on a floor of our university and asked 15 participants to carry a name tag with a Bluetooth Low Energy beacon during their daily life. Five kinds of tasks based on dialogue scenarios are posted to the approaching participants. Participants can respond to these tasks through a touchscreen. The period of the experiment was three weeks. To get the data in an ideal environment, during the first week, we asked all the participants to respond to the utterance from the interactive signage whenever they hear the voice message. During the next two weeks, participants were not asked to respond to the task definitely to get the data in the real environment. The result of the experiment showed that our proposed interactive signage could induce behavior change effectively. Based on the result of experiment, we updated our interactive signage system by adding response time (the time passed from showing contents until user respond), record function, and voice feedback function. Furthermore, to collect the data of response time that is considered as a part of users' reactions, we conducted an additional experiment with the same participants in previous experiment (except for one missing participant) for one week after updating the system. In the additional experiment, the participants were not asked to respond to the utterance definitely. As a result, it is shown that the behavior change by the proposed signage is still effectively induced. We also analyzed the relationship between the day passed and the response rate of each task type. The result shows that the number of ignorance of personal task and check task does not rise even as the time passes..
13. Yukitoshi Kashimoto, Yutaka Arakawa, Keiichi Yasumoto, Room measurement tool combining ultrasonic and inertial sensors in smartphones, International Journal of Ad Hoc and Ubiquitous Computing, 10.1504/IJAHUC.2019.100779, 31, 3, 189-199, 2019.01, Obtaining accurate floor plans of buildings is critical for optimising indoor geographic information system (GIS) applications. In this paper, we present a room measurement tool that utilises a smartphone equipped with an ultrasonic sensor. To take measurements, users complete a lap along the walls of all of the rooms. Then the tool accurately estimates the shape and size of them by tracking the walking paths of users and measuring the distance from the path to the walls with ultrasonic sensors. To track walking paths, we utilise inertial sensors embedded in the smartphone to estimate walking steps and turns, and the ultrasonic sensors to estimate the stride length when walking toward the wall. To account for such adjacent objects as bookshelves that decrease the accuracy of room size estimation, we used a mixed Gaussian filter. Our experimental results show that our tool considerably improved the estimation accuracy of the room shape and size..
14. Yutaka Arakawa, Sensing and changing human behavior for workplace wellness, Journal of information processing, 10.2197/ipsjjip.27.614, 27, 614-623, 2019.01, Recently, companies have begun to care more about the well-being of their employees. With the spread of sensors, the Internet of Things, and artificial intelligence, the movement to build a better working environment by utilizing these technologies has been spreading. Especially, research on behavior that can change lifestyle habits is becoming popular. In this paper, we summarize workplace behavior research and projects for sensing and changing human behavior in a workplace and aim to improve the productivity and wellness of employees. Also, we introduce concepts for future workplaces and some of our related achievements. For physical state sensing, we have developed a continuous posture-sensing chair, which will soon be available commercially. For internal state sensing, we propose a method for estimating quality of life with wearable sensors. Our system have already achieved to estimate QoL (Quality of Life) around 90% with only 9 questions. In addition, we propose interactive digital signage to provide habit-changing reminders. Through one month experiment, we confirmed that our system can be feasible in daily life..
15. Yugo Nakamura, Teruhiro Mizumoto, Hirohiko Suwa, Yutaka Arakawa, Hirozumi Yamaguchi, Keiichi Yasumoto, In-situ resource provisioning with adaptive scale-out for regional IoT services, 3rd ACM/IEEE Symposium on Edge Computing, SEC 2018 Proceedings - 2018 3rd ACM/IEEE Symposium on Edge Computing, SEC 2018, 10.1109/SEC.2018.00022, 203-213, 2018.12, In an era where billions of IoT devices have been deployed, edge/fog computing paradigms are attracting attention for their ability to reduce processing delays and communication overhead. In order to improve Quality of Experience (QoE) of regional IoT services that create timely geo-spatial information in response to users’ queries, it is important to efficiently allocate sufficient resources based on the computational demand of each service. However since edge/fog devices are assumed to be heterogeneous (in terms of their computational power, network performance to other devices, deployment density, etc.), provisioning computational resources according to computational demand becomes a challenging constrained optimization problem. In this paper, we formulate a delay constrained regional IoT service provisioning (dcRISP) problem. dcRISP assigns computational resources of devices based on the demand of the regional IoT services in order to maximize users’ QoE. We also present dcRISP+, an extension of dcRISP, that enables resource selection to extend beyond the initial area in order to satisfy increasing computational demands. We propose a provisioning algorithm, in-situ resource area selection with adaptive scale out and in-situ task scheduling based on a tabu search, to solve the dcRISP+ problem. We conducted a simulation study of a tourist area in Kyoto where 4,000 IoT devices and 3 types of IoT services were deployed. Results show that our proposed algorithms can obtain higher user QoE compared to conventional resource provisioning algorithms..
16. Yuki Matsuda, Dmitrii Fedotov, Yuta Takahashi, Yutaka Arakawa, Keiichi Yasumoto, Wolfgang Minker, EmoTour
Estimating Emotion and Satisfaction of Users Based on Behavioral Cues and Audiovisual Data, Sensors (Basel, Switzerland), 10.3390/s18113978, 18, 11, 2018.11, With the spread of smart devices, people may obtain a variety of information on their surrounding environment thanks to sensing technologies. To design more context-aware systems, psychological user context (e.g., emotional status) is a substantial factor for providing useful information in an appropriate timing. As a typical use case that has a high demand for context awareness but is not tackled widely yet, we focus on the tourism domain. In this study, we aim to estimate the emotional status and satisfaction level of tourists during sightseeing by using unconscious and natural tourist actions. As tourist actions, behavioral cues (eye and head/body movement) and audiovisual data (facial/vocal expressions) were collected during sightseeing using an eye-gaze tracker, physical-activity sensors, and a smartphone. Then, we derived high-level features, e.g., head tilt and footsteps, from behavioral cues. We also used existing databases of emotionally rich interactions to train emotion-recognition models and apply them in a cross-corpus fashion to generate emotional-state prediction for the audiovisual data. Finally, the features from several modalities are fused to estimate the emotion of tourists during sightseeing. To evaluate our system, we conducted experiments with 22 tourists in two different touristic areas located in Germany and Japan. As a result, we confirmed the feasibility of estimating both the emotional status and satisfaction level of tourists. In addition, we found that effective features used for emotion and satisfaction estimation are different among tourists with different cultural backgrounds..
17. Tatsuya Morita, Kenta Taki, Manato Fujimoto, Hirohiko Suwa, Yutaka Arakawa, Keiichi Yasumoto, BLE Beacon-based Activity Monitoring System toward Automatic Generation of Daily Report, 2018 IEEE International Conference on Pervasive Computing and Communications Workshops, PerCom Workshops 2018 2018 IEEE International Conference on Pervasive Computing and Communications Workshops, PerCom Workshops 2018, 10.1109/PERCOMW.2018.8480348, 788-793, 2018.10, As the world's population of senior citizens continues to grow, the burdens on the professionals who care for them (carers) are also increasing. In nursing homes, carers need to make a daily report for each resident aiming to improve his/her quality of life. However, in the present understaffed situation, it is difficult and burdensome for carers to record the resident's activity in detail since each carer needs to take care of several residents at the same time. In this paper, we propose an automatic daily report generation system which can monitor the activity of multiple residents in nursing homes. Knowing that important activities such as toilet, bathing, rehabilitation and so on take place in specific areas in a nursing home, it is possible to record residents' activities by tracking their stay areas and movement between the areas within the day. Our proposed system estimates stay areas of multiple residents by machine learning for RSSI values that are sent from BLE beacons attached to residents and received at BLE scanners deployed over multiple areas, and records activities of the residents determined based on their estimated stay areas. The proposed system can also output a daily report of each resident based on the recorded data. We carried out a five-day experiment with four elderly participants in a nursing home and evaluated activity estimation accuracy by leave-one-person-out cross-validation. As a result, our proposed system achieved the weighted average F-measure of 81.6%..
18. Shoya Ishimaru, Nicolas Großmann, Andreas Dengel, Carina Heisel, Pascal Klein, Jochen Kuhn, Ko Watanabe, Yutaka Arakawa, Demo
Hypermind builder - Pervasive user interface to create intelligent interactive documents, 2018 Joint ACM International Conference on Pervasive and Ubiquitous Computing, UbiComp 2018 and 2018 ACM International Symposium on Wearable Computers, ISWC 2018 UbiComp/ISWC 2018 - Adjunct Proceedings of the 2018 ACM International Joint Conference on Pervasive and Ubiquitous Computing and Proceedings of the 2018 ACM International Symposium on Wearable Computers, 10.1145/3267305.3267667, 357-360, 2018.10, We introduce a Graphical User Interface (GUI) to create intelligent interactive documents for everyone. The intelligent interactive document refers to a document displaying contents dynamically according to a reader's behavior. To the best of our knowledge, creating such documents requires a certain amount of efforts and implementation skills. By utilizing our system, users including non-technological experts can create interactive documents without any programming. Our system supports many people to enhance the possibility of designing new human-document interactions..
19. Kotone Senju, Teruhiro Mizumoto, Hirohiko Suwa, Yutaka Arakawa, Keiichi Yasumoto, Designing Strategy for Resolving Maldistribution of Vehicles in One-Way Car-Sharing through Active Trip Request to Potential Users, 2018 IEEE International Conference on Pervasive Computing and Communications Workshops, PerCom Workshops 2018 2018 IEEE International Conference on Pervasive Computing and Communications Workshops, PerCom Workshops 2018, 10.1109/PERCOMW.2018.8480256, 83-88, 2018.10, Recently, one-way car-sharing service that allows a user to drop the vehicle off at the destination has been started. However, it has not been as popular as expected mainly because it cannot assure the existence of an available vehicle at the start station or a vacant parking slot at the destination station. At this moment, the company staff are responsible for moving the vehicles to certain stations manually. Therefore, it is very costly. In order to reduce costs and make more efficient use of vehicles in one-way car-sharing service, we propose to involve a future potential user to move vehicles. We assume that there exist some requested one-way trips. Our method inserts a new trip among the existing trips for maximizing the number of successful trips. This trip is called 'a system request trip.' We assume that the system request trip can be realized by changing a future schedule or asking future potential users who want to get some rewards. In this paper, we analyzed how each user uses vehicles in one-way car-sharing service by using the past data of demonstration experiment conducted by a car-sharing company in Tokyo, Japan. Based on the analysis result, we examined how to request each user..
20. Yuki Matsuda, Dmitrii Fedotov, Yuta Takahashi, Yutaka Arakawa, Keiichi Yasumoto, Wolfgang Minker, Emotour
Multimodal emotion recognition using physiological and audio-visual features, 2018 Joint ACM International Conference on Pervasive and Ubiquitous Computing, UbiComp 2018 and 2018 ACM International Symposium on Wearable Computers, ISWC 2018 UbiComp/ISWC 2018 - Adjunct Proceedings of the 2018 ACM International Joint Conference on Pervasive and Ubiquitous Computing and Proceedings of the 2018 ACM International Symposium on Wearable Computers, 10.1145/3267305.3267687, 946-951, 2018.10, To design more context-aware systems for smart environments, especially smart cities, the psychological user status such as emotion should be considered in addition to environmental information. In this study, we focus on the tourism domain as a typical use case, and propose a multimodal tourist emotion recognition method during the sightseeing. We employ behavioural cues (eye and head/body movements) and audio-visual features to recognise emotion. As a result of real-world experiments with tourists, we achieved up to 0.71 of average recall score in 3-class emotion recognition task with feature level fusion..
21. Elder A.H. Akpa, Masashi Fujiwara, Yutaka Arakawa, Hirohiko Suwa, Keiichi Yasumoto, GIFT
Glove for Indoor Fitness Tracking System, 2018 IEEE International Conference on Pervasive Computing and Communications Workshops, PerCom Workshops 2018 2018 IEEE International Conference on Pervasive Computing and Communications Workshops, PerCom Workshops 2018, 10.1109/PERCOMW.2018.8480211, 52-57, 2018.10, It has been intensively demonstrated that physical activity can enhance the mental and physical health of practitioners. In recent years, fitness activities became the most common way to engage in physical activities. In this paper, we propose a smart-glove based fitness activity tracking system that can detect athletes activities in any indoor fitness facility, with no need of attaching multiple sensors on the athlete's body. The system adopts force sensitive resistor (FSR) sensors to identify the type of exercise by analyzing the pressure distribution in the hand palm during fitness activities. To evaluate the performance of our proposed system, we ran a pilot study with 10 healthy participants over 10 common fitness activities. The experimental results showed an overall recognition accuracy rate of 87%. We believe the promising results would contribute to the works on personal assisted coaching systems and create enjoyable experiences when performing fitness activities..
22. Masashi Takata, Manato Fujimoto, Keiichi Yasumoto, Yugo Nakamura, Yutaka Arakawa, Investigating the capitalize effect of sensor position for training type recognition in a body weight training support system, 2018 Joint ACM International Conference on Pervasive and Ubiquitous Computing, UbiComp 2018 and 2018 ACM International Symposium on Wearable Computers, ISWC 2018 UbiComp/ISWC 2018 - Adjunct Proceedings of the 2018 ACM International Joint Conference on Pervasive and Ubiquitous Computing and Proceedings of the 2018 ACM International Symposium on Wearable Computers, 10.1145/3267305.3267504, 1404-1408, 2018.10, A body weight training (BWT) means the training which utilizes the self-weight instead of the weight machine. The feedback of form and proper training menu recommendation is important for maximizing the effect of BWT. The objective of this study is to realize a novel support system which allows beginners to perform effective BWT alone, under wearable computing environment. To make an effective feedback, it is necessary to recognize BWT type with high accuracy. However, since the accuracy is greatly affected by the position of wearable sensors, we need to know the sensor position which achieves the high accuracy in recognizing the BWT type. We investigated 10 types BWT recognition accuracy for each sensor position. We found that waist is the best position when only 1 sensor is used. When 2 sensors are used, we found that the best combination is of waist and wrist. We conducted an evaluation experiment to show the effectiveness of sensor position. As a result of leave-one-person-out cross-validation from 13 subjects to confirm validity, we calculated the F-measure of 93.5% when sensors are placed on both wrist and waist..
23. Yugo Nakamura, Yoshinori Umetsu, Jose Paolo Talusan, Keiichi Yasumoto, Wataru Sasaki, Masashi Takata, Yutaka Arakawa, Multi-stage activity inference for locomotion and transportation analytics of mobile users, 2018 Joint ACM International Conference on Pervasive and Ubiquitous Computing, UbiComp 2018 and 2018 ACM International Symposium on Wearable Computers, ISWC 2018 UbiComp/ISWC 2018 - Adjunct Proceedings of the 2018 ACM International Joint Conference on Pervasive and Ubiquitous Computing and Proceedings of the 2018 ACM International Symposium on Wearable Computers, 10.1145/3267305.3267526, 1579-1588, 2018.10, In this paper, we, Ubi-NUTS Japan, introduce a multi-stage activity inference method that can recognize a user's mode of locomotion and transportation using mobile device sensors. We use the Sussex-Huawei Locomotion-Transportation (SHL) dataset to tackle the SHL recognition challenge, where the goal is to recognize 8 modes of locomotion and transportation (still, walk, run, bike, car, bus, train, and subway) activities from the inertial sensor data of a smartphone. We adopt a multi-stage approach where the 8 class classification problem is divided into multiple sub-problems considering the similarity of each activity. Multimodal sensor data collected from a mobile phone are inferred using a proposed pipeline that combines feature extraction and 4 different types of classifiers generated using the random forest algorithm. We evaluated our method using data from over 271 hours of daily activities of 1 participant and the 5-fold cross-validation. Evaluation results demonstrate that our method clearly recognizes the 8 types of activities with an average F1-score of 97%..
24. Yutaka Arakawa, Yugo Nakamura, Hirohiko Suwa, Yoshinori Umetsu, Manato Fujimoto, Keiichi Yasumoto, Poster
Feasibility study toward a battery-free place recognition system based on solar cells, 2018 Joint ACM International Conference on Pervasive and Ubiquitous Computing, UbiComp 2018 and 2018 ACM International Symposium on Wearable Computers, ISWC 2018 UbiComp/ISWC 2018 - Adjunct Proceedings of the 2018 ACM International Joint Conference on Pervasive and Ubiquitous Computing and Proceedings of the 2018 ACM International Symposium on Wearable Computers, 10.1145/3267305.3267624, 1-4, 2018.10, In this paper, we propose a battery-free place recognition system that utilizes solar-cells as a sensor for localization. Our system combines multiple solar cells having different characteristics against the light environment. As an initial work, we select five kinds of solar cells available in the market and investigate the characteristics of them. Then, we show a potential for estimating the place based on the variation of electricity amounts generated from solar cells. Finally, we show that our proposed system distinguish nine places with 88.0% accuracy..
25. Kazuhito Umeki, Yugo Nakamura, Manato Fujimoto, Yutaka Arakawa, Keiichi Yasumoto, Real-Time Congestion Estimation in Sightseeing Spots with BLE Devices, 2018 IEEE International Conference on Pervasive Computing and Communications Workshops, PerCom Workshops 2018 2018 IEEE International Conference on Pervasive Computing and Communications Workshops, PerCom Workshops 2018, 10.1109/PERCOMW.2018.8480395, 430-432, 2018.10, Recently, there is a growing demand to know con- gestion information on sightseeing spots in real-time to provide a satisfactory tour plan to tourists. Many studies on a congestion estimation have been conducted so far. However, most of them suffer from high deployment/operation costs and/or rely on contributions by users with smartphones/sensors. In this paper, we propose a novel system that estimates congestion of sightseeing spots in real-time without attaching any device to tourists by observing the distribution of per-RSSI intensity occurrences in each time window when beacon signals are periodically sent between BLE (Bluetooth Low Energy) transceivers installed in sightseeing spots. In other words, our system can estimate the congestion degree in sightseeing spots simply by using the property of RSSI intensity which dramatically changes depending on the number of people. Therefore, the proposed system is simple and low cost and can estimate the congestion easily without any special devices attached to tourists. In the demonstration, we show the congestion degree in three levels (low, medium, and high) changing in real-time depending on the number of audience in the demonstration site..
26. Masashi Fujiwara, Kazuki Moriya, Wataru Sasaki, Manato Fujimoto, Yutaka Arakawa, Keiichi Yasumoto, A smart fridge for efficient foodstuff management with weight sensor and voice interface, 47th International Conference on Parallel Processing, ICPP 2018 47th International Conference on Parallel Processing, ICPP 2018 Workshop Proceedings, 10.1145/3229710.3229727, 2018.08, Emerging smart appliances provide us with the opportunity of understanding peoples' in-depth daily life behavior patterns, through analyzing their operation states. Smart fridges, for example, can help us estimate the timing and content of meals of household members. Several smart fridges already exist. However, they have the following problems: high cost, a risk of privacy leakage through camera, and inability of tracking incremental consumption of food-stuffs. In this paper, to address these problems, and to realize smooth in-fridge foodstuff management, we propose a smart fridge with a weight sensor and a voice interface. The fridge stores the name and weight of each food item in a database. When a user places an item, whose information is not already stored in the database, the system supports the user to easily register the information with the weight sensor and the voice interface. In addition, we propose three input methods for efficient association between foodstuff names and their weights: sequential, asynchronous parallel, and synchronous parallel methods. We developed a prototype of our proposed smart fridge system and conducted a preliminary experiment with three participants to register foodstuffs and compared the time for registration between the proposed method and a popular existing smartphone application for in-fridge foodstuff management. As a result, we confirmed that the proposed system can register the foodstuffs in hands-free with comparable time to the existing application..
27. Dmitrii Fedotov, Yuki Matsuda, Yuta Takahashi, Yutaka Arakawa, Keiichi Yasumoto, Wolfgang Minker, Towards estimating emotions and satisfaction level of tourist based on eye gaze and head movement, 4th IEEE International Conference on Smart Computing, SMARTCOMP 2018 Proceedings - 2018 IEEE International Conference on Smart Computing, SMARTCOMP 2018, 10.1109/SMARTCOMP.2018.00036, 399-404, 2018.07, Following the increase in demand for 'smart tourism,' various tourist information becomes available. Current tourist guidance systems can provide many possible routes around the city, which are usually based on an optimal distance and time or popularity of the place. To design more enjoyable tourist routes, we should be aware of tourist's perception of the urban environment. In this paper, we propose the methodology of estimating the tourist emotions and satisfaction level by analysing physiological features, such as head movement and eye gaze. Features derived from raw sensor data have the correlation up to 0.58 with emotion and satisfaction labels. This study also shows the differences in feature/label dependencies between different touristic areas and highlights the challenges of tourist satisfaction estimation..
28. Shogo Kawanaka, Yukitoshi Kashimoto, Aryan Firouzian, Yutaka Arakawa, Petri Pulli, Keiichi Yasumoto, Approaching vehicle detection method with acoustic analysis using smartphone for elderly bicycle driver, 10th International Conference on Mobile Computing and Ubiquitous Network, ICMU 2017 2017 10th International Conference on Mobile Computing and Ubiquitous Network, ICMU 2017, 10.23919/ICMU.2017.8330069, 1-6, 2018.04, More than 60 percentage of fatal accidents while riding a bicycle is caused by elderly people over 65 years old. The main cause is the detection delay of approaching vehicle caused by the decrease of cognitive function due to aging. In this paper, we propose an approaching vehicle detection method using a smartphone aiming to support bicycle operation to prevent elderly people from fatal accidents while riding a bicycle vehicle. Among various sensors embedded in a smartphone, we focus on microphone as the most suitable sensor for detecting an approaching vehicle. We collected sound data in a real environment and created an approaching vehicle detection model by using machine learning. Finally, as a result of accuracy evaluation with 10-fold cross-validation, we confirmed that it can detect approaching vehicle with an average F-value of 97.4 [%]..
29. Yutaka Arakawa, Keiichi Yasumoto, Krita Pattamasiriwat, Teruhiro Mizumoto, Improving recognition accuracy for activities of daily living by adding time and area related features, 10th International Conference on Mobile Computing and Ubiquitous Network, ICMU 2017 2017 10th International Conference on Mobile Computing and Ubiquitous Network, ICMU 2017, 10.23919/ICMU.2017.8330104, 1-6, 2018.04, Recognizing the activities of daily living (ADL) of residents in housing is indispensable for operating Daily Life Support Services such as Elderly Monitoring, Smart Home Automation, and Health Support. However, the existing methods have various problems: invasion of privacy, limited target activities, low recognition accuracy, initial installation cost, and long recognition time. As our prior work, we proposed a real-time ADL recognition method using indoor positioning sensor and power meters. We got a result that the method can recognize ten types of ADL with the average accuracy of 79%. However, the accuracy of some activities such as work/study and bathroom-related were not satisfactory. In this work, we aim to improve the accuracy of our prior method by newly adding several new time and are related features such as time slot when activity occurs, staying time in the same area, and previous position. As a result, we could achieve 82% of average recognition accuracy for 10 different activities..
30. Kazuki Fujisawa, Yuko Hirabe, Hirohiko Suwa, Yutaka Arakawa, Keiichi Yasumoto, Automatic live sport video streams curation system from user generated media, Sports Media, Marketing, and Management Breakthroughs in Research and Practice, 10.4018/978-1-5225-5475-2.ch022, 417-435, 2018.03, Emerging Internet of Things (IoT) technologies will allow spectators in a sport game to produce various video streams from various angles. With existing technologies, however, it is difficult to process massive and various data streams for multi-channel contents in real-time. To solve this problem, we aim to construct a software agent (called "Curator") that compiles video contents automatically according to his/ her values. In this paper, we propose a system to automatically switch multiple video streams that general sports spectators have taken using Random Forests classifier. Meta data such as image feature data and game progress data is extracted for each video scene as the input of the classifier. For evaluation, we constructed a camera switching timing estimation model using the live TV broadcast of some baseball game data. A video of another baseball game was curated with the constructed model. As a result, our system predicted the camera switching timing with accuracy (F-measure) of 85.3% on weighted average for the base camera work and 99.7% for the fixed camera work..
31. Yasuhiro Otoda, Teruhiro Mizumoto, Yutaka Arakawa, Chihiro Nakajima, Mitsuhiro Kohana, Motohiro Uenishi, Keiichi Yasumoto, Census
Continuous posture sensing chair for office workers, 2018 IEEE International Conference on Consumer Electronics, ICCE 2018 2018 IEEE International Conference on Consumer Electronics, ICCE 2018, 10.1109/ICCE.2018.8326275, 1-2, 2018.03, Sitting on a chair with incorrect posture, or the same posture for a long time, causes the burden on the waist and shoulders of workers, leading to mental stress and poor work efficiency. It is therefore important to measure workers' sitting posture and advice on how to improve the posture or notify them to either adjust their posture or take a break from sitting. To achieve this, it is necessary to continuously measure how a worker is sitting without affecting the worker's ability to complete their tasks. We developed a sensing chair called 'Census' satisfying these requirements. This sensing chair has a function that is able to classify the sitting posture of workers with an accuracy of 80.1%..
32. Chishu Amenomori, Teruhiro Mizumoto, Hirohiko Suwa, Yutaka Arakawa, Keiichi Yasumoto, A method for simplified HRQOL measurement by smart devices, 7th International Conference on Wireless Mobile Communication and Healthcare, MobiHealth 2017 Wireless Mobile Communication and Healthcare - 7th International Conference, MobiHealth 2017, Proceedings, 10.1007/978-3-319-98551-0_11, 91-98, 2018.01, Health-related quality of life (HRQOL) is a useful indicator that rates a person’s activities in various physical, mental and social domains. Continuously measuring HRQOL can help detect the early signs of declines in these activities and lead to steps to prevent such declines. However, it is difficult to continuously measure HRQOL by conventional methods, since its measurement requires each user to answer burdensome questionnaires. In this paper, we propose a simplified HRQOL measurement method for a continuous HRQOL measurement which can reduce the burden of questionnaires. In our method, sensor data from smart devices and the questionnaire scores of HRQOL are collected and used to construct a machine-learning model that estimates the score for each HRQOL questionnaire item. Our experiment result showed our method’s potential and found effective features for some questions..
33. Tatsuya Morita, Kenta Taki, Manato Fujimoto, Hirohiko Suwa, Yutaka Arakawa, Keiichi Yasumoto, Beacon-Based Time-Spatial Recognition toward Automatic Daily Care Reporting for Nursing Homes, Journal of Sensors, 10.1155/2018/2625195, 2018, 2018.01, As the world's population of senior citizens continues to grow, the burden on the professionals who care for them (carers) is also increasing. In nursing homes, carers often write daily reports to improve the resident's quality of life. However, since each carer needs to simultaneously care for multiple residents, they have difficulty thoroughly recording the activities of residents. In this paper, we address this problem by proposing an automatic daily report generation system that monitors the activities of nursing home residents. The proposed system estimates the multiple locations (areas) at which residents are situated with a BLE beacon, using a variety of methods to analyze the RSSI values of BLE signals, and recognizes the activity of each resident from the estimated area information. The information of the estimated activity of residents is stored in a server with timestamps, and the server automatically generates daily reports based on them. To show the effectiveness of the proposed system, we conducted an experiment for five days with four participants in cooperation with an actual nursing home. We determined the proposed system's effectiveness with the following four evaluations: (1) comparison of performance of different machine-learning algorithms, (2) comparison of smoothing methods, (3) comparison of time windows, and (4) evaluation of generated daily reports. Our evaluations show the most effective combination pattern among 156 patterns to accurately generate daily reports. We conclude that the proposed system has high effectiveness, high usability, and high flexibility..
34. Tatsuya Morita, Masashi Fujiwara, Yutaka Arakawa, Hirohiko Suwa, Keiichi Yasumoto, Energy harvesting sensor node toward zero energy in-network sensor data processing, 9th EAI International Conference on Mobile Computing, Applications, and Services, MobiCASE 2018 Mobile Computing, Applications, and Services - 9th International Conference, MobiCASE 2018, Proceedings, 10.1007/978-3-319-90740-6_13, 210-215, 2018.01, In this paper, we aiming to realize near-zero energy distributed IoT systems that do not need a battery, we design and implement a novel energy harvesting (EH) sensor node. The proposed EH sensor node consists of a solar panel, an energy charging/discharging circuit and a SenStick, an existing sensor node including 8 different types of sensors and BLE communication interface. We demonstrate that the proposed EH sensor node works in an indoor environment by harvesting power from indoor lights, periodically measuring sensor data (temperature, humidity, atmospheric pressure, UV, and illuminance) and by sending the data by BLE communication. The received information is visualized through a web application running on a PC..
35. Edith Talina Luhanga, Akpa Akpro Elder Hippocrate, Hirohiko Suwa, Yutaka Arakawa, Keiichi Yasumoto, Identifying and Evaluating User Requirements for Smartphone Group Fitness Applications, IEEE Access, 10.1109/ACCESS.2018.2793844, 6, 3256-3269, 2018.01, Social support can improve adherence to physical activity and healthy eating behavior change, and recently, smartphone fitness applications which provide interventions to groups of users are increasingly popular. However, the types of social support provided in the applications, and the features/approaches used to offer the support, vary widely. It is unknown which approach is the best to meet users' requirements. We conducted a mixed methods study to identify user requirements for social support in group fitness applications. We then developed MyFitnessTeam based on these requirements and evaluated it in a six-week field study. We found that participants desired informational and emotional support, and for group fitness applications to provide daily challenges that they could complete with their support network. MyFitnessTeam significantly improved adherence to fitness behaviors, with men having significantly higher adherence levels than women and participants who were inactive at baseline achieving similar adherence levels to the most baseline-Active participants. Groups of friends were more likely to exchange informational support but emotional support was low for both friends and strangers, due to lack of knowledge on when and how to offer such support. We propose five design recommendations to promote supportive interactions in group fitness applications..
36. Akira Fukuda, Hisazumi Kenji, Tsunenori Mine, Shigemi Ishida, Takahiro Ando, Shota Ishibashi, Shigeaki Tagashira, Kunihiko Kaneko, Yutaka Arakawa, Weiqiang Kong, Guoqiang Li, Toward sustainable smart mobility information infrastructure platform
Project overview, Studies in Computational Intelligence, 10.1007/978-3-319-70636-8_3, 35-46, 2018.01, Smart mobility systems, which include Intelligent Transportation Systems (ITS) and smart energy ones, become more important. There is, however, lack of its platform studies. This paper proposes a sustainable information infrastructure project for smart mobility systems. The project pursues issues that establish an information infrastructure architecture and a seamless development method chain for it. The project has mainly two features: (1) applying life-cycle-oriented methods, which are a cycle from system development phase to operation phase. In addition, these methods are applied to real world applications, and (2) dealing with an uncertainty that occurs in system development upper phase. This paper describes an overview of the project..
37. Yuko Hirabe, Manato Fujimoto, Yutaka Arakawa, Hirohiko Suwa, Keiichi Yasumoto, Effect on Group Detection Based on Human Proximity for Human Relationship Extraction in Daily Life, 46th International Conference on Parallel Processing Workshops, ICPPW 2017 Proceedings - 46th International Conference on Parallel Processing Workshops, ICPPW 2017, 10.1109/ICPPW.2017.14, 1-7, 2017.09, In this paper, we investigate an effect on group detection based on human proximity depending on RSSI values, measured by BLE signals. To realize the investigation, we present a novel method for detecting groups. In the method, we developed a smartphone application for measurement of RSSI values of BLE, and determine a threshold of RSSI values which selected experimentally by making the propagation characteristics of BLE signal. To show the effectiveness of proposed method, we evaluated the method through a series of experiments and investigated the effect on group detection by the difference of human proximity. As the results, we found that the group detection was affected by the difference of human proximity..
38. Kazuma Nagano, Yutaka Arakawa, Keiich Yasumoto, Trackthink
A tool for tracking a thought process on web search, 2017 ACM International Joint Conference on Pervasive and Ubiquitous Computing and ACM International Symposium on Wearable Computers, UbiComp/ISWC 2017 UbiComp/ISWC 2017 - Adjunct Proceedings of the 2017 ACM International Joint Conference on Pervasive and Ubiquitous Computing and Proceedings of the 2017 ACM International Symposium on Wearable Computers, 10.1145/3123024.3129267, 681-687, 2017.09, This paper proposes a tool for tracking a thought process in web searching because we considered that user's browsing history potentially contains the transition information of a thought process of how to collect information efficiently. In fact, we have few opportunities to look back own browsing way. Even if we check the enormous browsing logs, it is hard to convert them into sharable knowledge. Therefore, our tool measure the dwell time, the amount of scrolling and page contents and transition between pages for evaluating the importance of each page. In addition, our tool provides an editing function to summarize a thought process based on the importance of each page. Copyright held by the owner/author(s)..
39. Yukitoshi Kashimoto, Masashi Fujiwara, Manato Fujimoto, Hirohiko Suwa, Yutaka Arakawa, Keiichi Yasumoto, ALPAS
Analog-PIR-sensor-based activity recognition system in smarthome, 31st IEEE International Conference on Advanced Information Networking and Applications, AINA 2017 Proceedings - 31st IEEE International Conference on Advanced Information Networking and Applications, AINA 2017, 10.1109/AINA.2017.33, 880-885, 2017.05, These days, smart home applications such as a concierge service for residents, home appliance control and so on are attracting attention. In order to realize these applications, we strongly believe that we need a system which recognizes the various human activities accurately with a low cost device. There are many studies which work on the activity recognition in the smarthome. Moreover, we also have proposed the activity recognition technique in the smarthome by utilizing the digital-output-PIR sensor, door sensor, watt meter. However, the study has the challenge: we cannot distinguish between the similar tiny activities at the same place: 'eating' and 'reading' with sitting on a sofa. In order to cope with this challenge, we introduce ALPAS: analog-output-PIR-sensor-based activity recognition technique which recognizes the detailed activities of the user. Our technique recognizes the activity of the user by utilizing the machine learning. We evaluated the proposed technique in a smarthome which belongs to the authors' university. In the evaluation, three subjects performed four different activities with sitting on a sofa. As a result, we achieved F-Measure: 57.0%..
40. Kazuki Moriya, Eri Nakagawa, Manato Fujimoto, Hirohiko Suwa, Yutaka Arakawa, Aki Kimura, Satoko Miki, Keiichi Yasumoto, Daily living activity recognition with ECHONET Lite appliances and motion sensors, 2017 IEEE International Conference on Pervasive Computing and Communications Workshops, PerCom Workshops 2017 2017 IEEE International Conference on Pervasive Computing and Communications Workshops, PerCom Workshops 2017, 10.1109/PERCOMW.2017.7917603, 437-442, 2017.05, Recently, IoT (Internet of Things) technologies have been attracting increasing attention. Among many applications of IoT, homes can be the most promising target. One of the purposes to deploy IoT in homes is automatic recognition of activities of daily living (ADLs). It is expected that ADL recognition in homes enables many new services such as elderly people monitoring and low energy appliance control. In existing studies on ADL recognition, however, it is hard to build a system to acquire data for ADL recognition in terms of installation cost. In this paper, we propose a method that reduces costs of the ADL recognition system by using ECHONET Lite-ready appliances which are expected to be widely spread in the future. ECHONET Lite is a communication protocol for control and sensor networks in smart-homes and standardized as ISO/IEC-4-3. The proposed method utilizes information (e.g., on/off state) from appliances and motion sensors attached to them as features and recognizes ADLs through machine learning. To evaluate the proposed method, we collected data in our smart-home testbed while several participants are living there. As a result, the proposed method achieved about 68% classification accuracy for 9 different activities..
41. Cedric Konan, Hirohiko Suwa, Yutaka Arakawa, Keiichi Yasumoto, EmoBGM
Estimating sound's emotion for creating slideshows with suitable BGM, 2017 IEEE International Conference on Pervasive Computing and Communications Workshops, PerCom Workshops 2017 2017 IEEE International Conference on Pervasive Computing and Communications Workshops, PerCom Workshops 2017, 10.1109/PERCOMW.2017.7917587, 351-356, 2017.05, This paper presents a study about estimating the emotions conveyed in clips of background music (BGM) to be used in an automatic slideshow creation system. The system we aimed to develop, automatically tags each given pieces of background music with the main emotion it conveys, in order to recommend the most suitable music clip to the slideshow creators, based on the main emotions of embedded photos. As a first step of our research, we developed a machine learning model to estimate the emotions conveyed in a music clip and achieved 88% classification accuracy with cross-validation technique. The second part of our work involved developing a web application using Microsoft Emotion API to determine the emotions in photos, so the system can find the best candidate music for each photo in the slideshow. 16 users rated the recommended background music for a set of photos using a 5-point likert scale and we achieved an average rate of 4.1, 3.6 and 3.0 for the photo sets 1, 2, and 3 respectively of our evaluation task..
42. Ryota Koshiba, Yuko Hirabe, Manato Fujimoto, Hirohiko Suwa, Yutaka Arakawa, Keiichi Yasumoto, Group detection based on user-to-user distance in everyday life for office lunch group recommendation, 31st IEEE International Conference on Advanced Information Networking and Applications Workshops, WAINA 2017 Proceedings - 31st IEEE International Conference on Advanced Information Networking and Applications Workshops, WAINA 2017, 10.1109/WAINA.2017.43, 309-314, 2017.05, Companies have recently been introducing an event system called shuffle lunch, which aims to effectively utilize lunch breaks. The system has been garnering attention from many enterprises because it livens relationships and strengthens cooperation between departments and individual workers. In existing shuffle lunch systems, lunch groups are randomly generated. Random groups however, can cause problems. For example, some people might feel awkward about eating with new people, groups might not agree about when and where to eat, or some people may be absent. To form better lunch groups, the relationships between potential group members have to be known. In this study, we propose a method for dynamically detecting groups by using smartphones to measure the daily physical proximities of people. We also developed an Android application to realize our proposed method. We evaluated our system through a series of experiments and found that our proposed method can accurately detect groups, based on the proximities measured by the Android application..
43. Yukitoshi Kashimoto, Tatsuya Morita, Manato Fujimoto, Yutaka Arakawa, Hirohiko Suwa, Keiichi Yasumoto, Sensing activities and locations of senior citizens toward automatic daycare report generation, 31st IEEE International Conference on Advanced Information Networking and Applications, AINA 2017 Proceedings - 31st IEEE International Conference on Advanced Information Networking and Applications, AINA 2017, 10.1109/AINA.2017.34, 174-181, 2017.05, Recently, as elderly people population grows, the burdens on caretakers are getting larger. In daycare centers, caretakers make a daycare report aiming to improve the senior citizen's Quality of Life. However, in the present situation, it is difficult for caretakers to record the senior citizen's activity in detail, since each caretaker needs to take care of several senior citizens at the same time. To reduce the burden of caretakers, many elderly monitoring systems have been proposed so far, but most of them are not effective in the sense that they force the senior citizen to use dedicated devices such as smart phone and/or particular applications that are obtrusive and cumbersome for care receivers. In this paper, we propose a semi-automatic care-taking report generation system which can monitor movements/activity of senior citizens in daycare centers. Our proposed system estimates multiple locations (areas) where senior citizens are located with the BLE beacon, by utilizing RSSI of the Bluetooth radio wave. Also, the accelerometer implemented in the tag estimates the activity of the elderly. The information of the estimated area and activity is stored in a server with time stamp. The server generates the daycare report based on it. In order to evaluate the proposed system, we have deployed our system in a daycare center: Ikoi-no-ie 26. Evaluation result in Ikoi-no-ie 26 showed that our system estimated the subject's present area with F-measure: 80.6% and activity with F-measure: 73.8% and generated the daycare report..
44. Eri Nakagawa, Kazuki Moriya, Hirohiko Suwa, Manato Fujimoto, Yutaka Arakawa, Keiichi Yasumoto, Toward real-time in-home activity recognition using indoor positioning sensor and power meters, 2017 IEEE International Conference on Pervasive Computing and Communications Workshops, PerCom Workshops 2017 2017 IEEE International Conference on Pervasive Computing and Communications Workshops, PerCom Workshops 2017, 10.1109/PERCOMW.2017.7917620, 539-544, 2017.05, Automatic recognition of activities of daily living (ADL) can be applied to realize services to support user life such as elderly monitoring, energy-saving home appliance control, and health support. In particular, 'real-time' ADL recognition is essential to realize such a service that the system needs to know the user's current activity. There are many studies on ADL recognition. However, none of these studies address all of the following problems: (1) privacy intrusion due to the utilization of high privacy-invasive devices such as cameras and microphones; (2) limited number of recognizable activities; (3) low recognition accuracy; (4) high deployment and maintenance costs due to many sensors used; and (5) long recognition time. In our prior work, we proposed a system which solves the problems (1)-(4) to some extent by using user's position data and power consumption data of home electric appliances. In this paper, aiming to solve all the above problems including (5), we propose a new system by extending our prior work. To realize 'real-time' ADL recognition while keeping good recognition accuracy, we developed new power meters with higher sensing frequency and introduced new techniques such as adding new features, selecting the best subset of the features, and selecting the best training dataset used for machine learning. We collected the sensor data in our smart home facility for 11 days, and applied the proposed method to these sensor data. As a result, the proposed method achieved accuracy of 79.393% in recognizing 10 types of ADLs..
45. Yutaka Arakawa, Poster abstract
Empirical research on behavior change promoted by information technology, 16th ACM/IEEE International Conference on Information Processing in Sensor Networks, IPSN 2017 Proceedings - 2017 16th ACM/IEEE International Conference on Information Processing in Sensor Networks, IPSN 2017, 10.1145/3055031.3055068, 319-320, 2017.04, This paper shows the concept and design of an ongoing project about "behavior change", that is one of the keywords for realizing a sustainable society based on information technology such as IoT and AI. "Stand" function that Apple Watch has is a touchstone of the arrival of a new age. The watch commands a human to stand up or meditate. It is a start of intervention to our behavior from AI. However, it is not so bad because we know that this suggestion must be good for our health. Based on this experience, we started an empirical research on behavior change that consists of activity recognition, just-in-time intervention, and gamification..
46. Edgar Marko Trono, Manato Fujimoto, Hirohiko Suwa, Yutaka Arakawa, Keiichi Yasumoto, Generating pedestrian maps of disaster areas through ad-hoc deployment of computing resources across a DTN, Computer Communications, 10.1016/j.comcom.2016.12.003, 100, 129-142, 2017.03, Generating pedestrian maps of disaster areas is an important part of response operations. Maps aid responders in decision-making and show routes that lead evacuees to refuges. However, disasters can damage communication infrastructures, rendering Cloud-based mapping services inaccessible. Responders resort to paper maps, which are difficult to share and cannot recommend routes. In this study, we present a digital pedestrian map generation system for disasters. To realize the system, we addressed these challenges: (1) how to collect the required data and generate the map without Cloud-based computing resources, (2) how to share messages within the system without continuous, end-to-end networks, and (3) how to balance the load of map inference tasks. For (1), GPS traces are collected by responders exploring the area. Then, collected data are sent to Computing Nodes: commodity workstations that are deployed in the disaster area, for processing. For (2), the system establishes a Delay-Tolerant Network that uses Epidemic Routing to communicate across shorter-ranges and uses response vehicles as data ferries to communicate across longer-ranges. For (3), we propose a load balancing heuristic, which uses ferry route timetables and statistical information about the load of Computing Nodes to determine how to offload map inference tasks. We evaluate our system through experiments and simulations and show that it decreases the time needed to generate and deliver pieces of the map by approximately two hours in an extreme case with large quantities of data have to be processed..
47. Kazuki Kawamura, Hirohiko Suwa, Yuki Ogawa, Yutaka Arakawa, Keiichi Yasumoto, Toshizumi Ohta, Customer recommendation model to support real estate salespersons for a restaurant, Transactions of the Japanese Society for Artificial Intelligence, 10.1527/tjsai.WII-O, 32, 1, WII-O_1-WII-O_10, 2017.01, In this paper, we propose a recommendation model of application customer to reduce the time and cost of the salesperson by recommending the application customer to salesperson. The model is built based on customer information, premise information, and two new features which are extracted from salesperson’s feedback. Estimation precision is evaluated by three algorithms: SVM, Decision Tree and Random Forest. We applied three algorithm against five data sets. As a result, the highest estimation precision was 49.2% using RF against the data which selected by some important features (data 5). In the case of using the customer information and property information (data 3), estimation precision was 38.7%. Moreover in the case of adding new two features against that data (data 4), estimate precision was 44.2%. From comparison between data 3 and data 4, we clarified that the new two features increased the estimation precision. Also, from comparison between data 4 and data 5, we clarified that selecting some important features increased the estimation precision. In addition, according to the feedback from the ABC TENPO Inc which we are conducting joint research, our model increased the precision compared with the veteran salesperson..
48. Yugo Nakamura, Yutaka Arakawa, Takuya Kanehira, Masashi Fujiwara, Keiichi Yasumoto, SenStick
Comprehensive Sensing Platform with an Ultra Tiny All-In-One Sensor Board for IoT Research, Journal of Sensors, 10.1155/2017/6308302, 2017, 2017.01, We propose a comprehensive sensing platform called SenStick, which is composed of hardware (ultra tiny all-in-one sensor board), software (iOS, Android, and PC), and 3D case data. The platform aims to allow all the researchers to start IoT research, such as activity recognition and context estimation, easily and efficiently. The most important contribution is the hardware that we have designed. Various sensors often used for research are embedded in an ultra tiny board with the size of 50 mm (W) × 10 mm (H) × 5 mm (D) and weight around 3 g including a battery. Concretely, the following sensors are embedded on this board: acceleration, gyro, magnetic, light, UV, temperature, humidity, and pressure. In addition, this board has BLE (Bluetooth low energy) connectivity and capability of a rechargeable battery. By using 110 mAh battery, it can run more than 15 hours. The most different point from other similar boards is that our board has a large flash memory for logging all the data without a smartphone. By using SenStick, all the users can collect various data easily and focus on IoT data analytics. In this paper, we introduce SenStick platform and some case studies. Through the user study, we confirmed the usefulness of our proposed platform..
49. Yukitoshi Kashimoto, Tatsuya Morita, Manato Fujimoto, Yutaka Arakawa, Hirohiko Suwa, Keiichi Yasumoto, Implementation and evaluation of daycare report generation system based on BLE tag, 15th International Conference on Mobile and Ubiquitous Multimedia, MUM 2016 MUM 2016 - 15th International Conference on Mobile and Ubiquitous Multimedia, Proceedings, 10.1145/3012709.3016072, 327-329, 2016.12, Recently, as elderly people population grows, the burdens on caretakers are getting larger. In daycare center, caretakers make a daycare report aiming to improve the senior citizen's Quality of Life. However, in the aged society, it is difficult for caretakers to record the senior citizen's activity in detail, since each caretaker needs to take care of several senior citizens at the same time. In this paper, we propose a semi-automatic daycare report generation system. Our proposed system estimates the present area and activity of the senior citizen by utilizing the accelerometer-implemented-BLE-beacon tags and generate the daycare report. Based on the generated report, the caretaker works effectively. Evaluation result in a daycare center showed that our system estimated the subject's present area with F-measure: 80.6% and activity with F-measure: 73.8% and automatically generated the daycare report..
50. Yugo Nakamura, Hirohiko Suwa, Yutaka Arakawa, Hirozumi Yamaguchi, Keiichi Yasumoto, Design and Implementation of Middleware for IoT Devices toward Real-Time Flow Processing, 36th IEEE International Conference on Distributed Computing Systems Workshops, ICDCSW 2016 Proceedings - 2016 IEEE 36th International Conference on Distributed Computing Systems Workshops, ICDCSW 2016, 10.1109/ICDCSW.2016.37, 162-167, 2016.11, Thanks to rapid advance and penetration of IoT devices, it is becoming possible to sense almost every information of real-world. This urges us to utilize data streams continuously generated from IoT devices in real-Time. In this paper, aiming to locally process data streams by using computational resources of IoT devices, we propose middleware for IoT devices where the devices process data streams in real-Time and in a distributed manner. The proposed middleware provides four functions: (1) distribution of tasks issued by application software into sub-Tasks and distributed execution of the sub-Tasks over multiple IoT devices, (2) distribution of data streams over IoT devices, (3) real-Time analysis of the data streams, and (4) seamless integration of sensors and actuators. We have implemented a prototype of the proposed middleware for Raspberry Pi and show its basic performance..
51. Yukitoshi Kashimoto, Manato Fujimoto, Hirohiko Suwa, Yutaka Arakawa, Keiichi Yasumoto, Floor vibration type estimation with piezo sensor toward indoor positioning system, 2016 International Conference on Indoor Positioning and Indoor Navigation, IPIN 2016 2016 International Conference on Indoor Positioning and Indoor Navigation, IPIN 2016, 10.1109/IPIN.2016.7743667, 2016.11, These days, smart home applications such as a concierge service for residents, home appliance control and so on are attracting attention. In order to realize these applications, we strongly believe that we need an indoor positioning system which fulfills the following requirements: Req 1: high accuracy; Req 2: low installation cost; Req 3: small burden on the user; Req 4: low privacy invasion. There are several studies which work on the indoor positioning system. However, these previous works do not accomplish the requirements. In this paper, we present a piezo sensor-based indoor positioning system which estimates the position of the user by utilizing a piezo component attached on the floor. To realize the proposed positioning system, we have tackled two challenges. First challenge is the development of an indoor positioning technique. We cannot utilize TDoA technique that is used to estimate the distance from the target, since the calculation of vibration velocity is difficult. To cope with this challenge, we have developed a new technique which estimates the position of the user from floor vibrations caused by their actions. Second challenge is the selection of the feature vector to estimate the vibration type accurately. We have selected MFCC, FFT, and Envelope shape features from preliminary experiments. We have implemented the proposed system in our smart home testbed. We have evaluated the performance of the vibration type estimation technique. As a result, we have confirmed that our technique estimates the type with F-measure: 93.9%..
52. Edith Talina Luhanga, Akpa Akpro Elder Hippocrate, Hirohiko Suwa, Yutaka Arakawa, Keiichi Yasumoto, Happyinu
Exploring how to use games and extrinsic rewards for consistent food tracking behavior, 9th International Conference on Mobile Computing and Ubiquitous Networking, ICMU 2016 2016 9th International Conference on Mobile Computing and Ubiquitous Networking, ICMU 2016, 10.1109/ICMU.2016.7742088, 2016.11, Consistent food tracking is important for weight loss. Many people struggle with forming and maintaining the habit because it is time consuming and generally un-enjoyable. We describe the design and initial field evaluation of HappyInu, a virtual pet-care game that we developed to promote consistent food tracking. HappyInu uses daily notifications to remind users to track, provides photo-based food tracking to make the process simpler and gives virtual and cash rewards for motivation. In our pilot study, users were excited about the game-based approach and they wanted more in-game tasks and rewards to be offered. Intrinsic rewards were more motivating than cash, particularly pleasure (fun) and the need to contribute to something meaningful. However, users played HappyInu on a casual (non-daily) basis, just as they did with other smartphone games. In this paper, we discuss users' perceptions on the role of games for behavior change and the implications on game design..
53. Kazuki Moriya, Manato Fujimoto, Yutaka Arakawa, Keiichi Yasumoto, Indoor localization based on distance-illuminance model and active control of lighting devices, 2016 International Conference on Indoor Positioning and Indoor Navigation, IPIN 2016 2016 International Conference on Indoor Positioning and Indoor Navigation, IPIN 2016, 10.1109/IPIN.2016.7743623, 2016.11, In this paper, we propose an indoor localization method using a distance-illuminance model of lighting devices and trilateration. We propose a method that estimates distance from three controllable lighting devices based on the illuminance at the target point, by alternately turning on each of the devices. Then, the proposed method estimates the position of the target point based on trilateration. The proposed method are two merits. First, it can be realized at low cost because only three lighting devices and an illuminance sensor are required. Second, it is robust against influences by external lighting devices (or sunlight) since the proposed method measures the difference of the illuminance before and after turning on a lighting device. We conducted experiments in a room in an ordinary home environment and confirmed that the proposed method could estimate the position of the illuminance sensor within 0.5m error on average..
54. Eri Nakagawa, Kazuki Moriya, Hirohiko Suwa, Manato Fujimoto, Yutaka Arakawa, Toshiyuki Hatta, Shotaro Miwa, Keiichi Yasumoto, Investigating recognition accuracy improvement by adding user's acceleration data to location and power consumption-based in-home activity recognition system, 13th International Conference on Mobile and Ubiquitous Systems: Computing, Networking and Services, MobiQuitous 2016 Adjunct Proceedings of the 13th International Conference on Mobile and Ubiquitous Systems Computing, Networking and Services, MobiQuitous 2016, 10.1145/3004010.3004036, 100-105, 2016.11, Recently, there are many studies on automatic recognition of activities of daily living (ADL) to provide various ser-vices such as elderly monitoring, intelligent concierge, and health support. In particular, real-time ADL recognition is essential to realize an intelligent concierge service since the service needs to know user's current or next activity for supporting it. We have been studying real-time ADL recognition using only user's position data and appliances' power consumption data which are considered to include less privacy information than audio and visual data. In the study, we found that some activities such as reading and operating smartphone that happen in similar conditions cannot be classified with only position and power data. In this paper, we propose a new method that adds the acceleration data from wearable devices for classifying activities happening in similar conditions with higher accuracy. In the proposed method, we use the acceleration data from a smart watch and a smartphone worn by user's arm and waist, respectively, in addition to user's position data and appliances' power consumption data, and construct a machine learning model for recognizing 15 types of target activities. We evaluated the recognition accuracy of 3 methods: our previous method (using only position data and power consumption data); the proposed method using the mean value and the standard deviation of the acceleration norm; and the pro-posed method using the ratio of the activity topics. We collected the sensor data in our smart home facility for 12 days, and applied the proposed method to these sensor data. As a result, the proposed method could recognize the activities with 57 % which is 12 % improvement from our previous method without acceleration data..
55. Yukitoshi Kashimoto, Kyoji Hata, Hirohiko Suwa, Manato Fujimoto, Yutaka Arakawa, Takeya Shigezumi, Kunihiro Komiya, Kenta Konishi, Keiichi Yasumoto, Low-cost and device-free activity recognition system with energy harvesting PIR and door sensors, 13th International Conference on Mobile and Ubiquitous Systems: Computing, Networking and Services, MobiQuitous 2016 Adjunct Proceedings of the 13th International Conference on Mobile and Ubiquitous Systems Computing, Networking and Services, MobiQuitous 2016, 10.1145/3004010.3006378, 6-11, 2016.11, Progress of IoT and ubiquitous computing technologies has strong anticipation to realize smart services in households such as efficient energy-saving appliance control and elderly monitoring. In order to put those applications into practice, high-accuracy and low-cost in-home living activity recognition is essential. Many researches have tackled living activity recognition so far, but the following problems remain: (i)privacy exposure due to utilization of cameras and microphones; (ii) high deployment and maintenance costs due to many sensors used; (iii) burden to force the user to carry the device and (iv) wire installation to supply power and communication between sensor node and server; (v) few recognizable activities; (vi) low recognition accuracy. In this paper, we propose an in-home living activity recognition method to solve all the problems. To solve the problems (i){(iv), our method utilizes only energy harvesting PIR and door sensors with a home server for data collection and processing. The energy harvesting sensor has a solar cell to drive the sensor and wireless communication modules. To solve the problems (v) and (vi), we have tackled the following challenges: (a) determining appropriate features for training samples; and (b) determining the best machine learning algorithm to achieve high recognition accuracy; (c) complementing the dead zone of PIR sensor semipermanently. We have conducted experiments with the sensor by five subjects living in a home for 2{3 days each. As a result, the proposed method has achieved F-measure: 62.8% on average..
56. Edgar Marko Trono, Manato Fujimoto, Hirohiko Suwa, Yutaka Arakawa, Keiichi Yasumoto, Milk carton
Family tracing and reunification system using face recognition over a DTN with deployed computing nodes, 13th International Conference on Mobile and Ubiquitous Systems: Computing, Networking and Services, MobiQuitous 2016 Adjunct Proceedings of the 13th International Conference on Mobile and Ubiquitous Systems Computing, Networking and Services, MobiQuitous 2016, 10.1145/3004010.3006380, 24-28, 2016.11, During the recovery period after disasters, Family Tracing and Reunification (FTR) is the process by which separated family members are reunited. Traditional FTR methods rely on paper-based registries and notice boards, which cannot automatically match missing person queries with existing records and cannot be efficiently disseminated. Furthermore, lost children or people with disabilities may not be capable of supplying the text-based personal information required by registry forms. Finally, current digital FTR systems require the Internet for data delivery and storage, which may be unavailable during a disaster scenario. To overcome these limitations, we propose the Milk Carton FTR system. Milk Carton uses the Eigenfaces face recognition algorithm to automatically match missing person queries with existing records, without requiring text-based personal information. The system uses Computing Nodes, commodity devices deployed in evacuation centers, to handle record and query creation, data storage, and matching. To handle data delivery without the Internet, Milk Carton leverages response team vehicles as data ferries. The ferries store, carry, and forward records and queries across the system. In this study, we present the design of the Milk Carton system and initial performance evaluations..
57. Manato Fujimoto, Seigi Matsumoto, Yutaka Arakawa, Keiichi Yasumoto, RecurChat
BLE-based message forwarding system with on-site application distribution, 9th International Conference on Mobile Computing and Ubiquitous Networking, ICMU 2016 2016 9th International Conference on Mobile Computing and Ubiquitous Networking, ICMU 2016, 10.1109/ICMU.2016.7742096, 2016.11, In this paper, we propose an ad-hoc communication system for a smartphone, which utilizes Bluetooth Low Energy (BLE). The proposed system is assumed to be used in disaster situation where the Internet connection is not available. It means that a smartphone cannot obtain any information as well as any new application because all the applications are distributed in the cloud such as App Store. However, our proposed system is equipped with the mechanism, called RecurShare, to distribute the applications on-site. In addition, our proposed system has the function to solve «Central-Peripheral problem» which stems from BLE hardware. Generally, a smartphone works as «Central» of BLE connection, and the connection between Centrals cannot be established. Therefore, it is not easy to realize a BLE-based ad-hoc communication system between smartphones except iPhone. Our proposed function utilizes a few peripheral-ready terminal as a router of the network for solving this problem. To evaluate the feasibility of our proposed system, we show that the proposed system can replicate the application on-site and also enable chat among Android smartphones even if some of them are Central-only terminal..
58. Yugo Nakamura, Yutaka Arakawa, Keiichi Yasumoto, Senstick
A rapid prototyping platform for sensorizing things, 9th International Conference on Mobile Computing and Ubiquitous Networking, ICMU 2016 2016 9th International Conference on Mobile Computing and Ubiquitous Networking, ICMU 2016, 10.1109/ICMU.2016.7742087, 2016.11, In this paper, we propose a novel rapid prototyping platform called SenStick, which is composed of both hardware and software. The main purpose of our platform is to sensorize our personal belongings easily and smart for recognizing our living activities. The most impressive point is its size. The size is 75mm(W) x 10mm(H) x 5mm(D) and its weight is around 3 (g) including a battery. On this tiny board, 8 sensors (acceleration, gyro, magnetic, light, UV, temperature, humidity, and pressure), flash memory, BLE, and battery are embedded in high density. The battery life in stand-alone mode is more than 12 hours. Second interesting point is the support software for iOS and Android OS. It can monitor the sensing data as well as can record the ground truth video simultaneously and synchronously. Furthermore, 3D CAD data of various case designs will be open for users in SenStick community site. As a result, SenStick enables everyone to sense every activities easily and smart..
59. Yuki Matsuda, Takashi Hasegaway, Ismail Arai, Yutaka Arakawa, Keiichi Yasumoto, Waistonbelt 2
A belt-type wearable device for monitoring abdominal circumference, posture and activity, 9th International Conference on Mobile Computing and Ubiquitous Networking, ICMU 2016 2016 9th International Conference on Mobile Computing and Ubiquitous Networking, ICMU 2016, 10.1109/ICMU.2016.7742089, 2016.11, In this paper, we propose a health support system «WaistonBelt 2,» which consists of a belt-type wearable device and a smartphone application. Our system aims to support users to obesity (the metabolic syndrome) that may lead to various adult diseases such as arteriosclerosis, heart disease or stroke. Our proposed device can automatically measure a circumference on the belt position when a user wears it by a rotary encoder, and monitor a tension of belt for recognizing posture and overeating. The measured data is transmitted to our application via Bluetooth. Stored values are visualized by graphs, and advices are given through the avatar based on the analyzed data. Through evaluation experiments, we confirmed that our proposed device achieves highly accurate measurement of the circumference on the belt position (average absolute error is 0.73 cm). We also confirmed that it is possible to realize a recognition system of posture and eating action using belt pressure sensing system..
60. Naoki Maeda, Yuko Hirabe, Yutaka Arakawa, Keiichi Yasumoto, COSMS
Unconscious stress monitoring system for office worker, 2016 ACM International Joint Conference on Pervasive and Ubiquitous Computing, UbiComp 2016 UbiComp 2016 Adjunct - Proceedings of the 2016 ACM International Joint Conference on Pervasive and Ubiquitous Computing, 10.1145/2968219.2971397, 329-332, 2016.09, To increase the productivity of people's work, one of the most important challenges is to proactively keep and improve their mental health in the office while continuously obtaining their physiological information. In this paper, aiming to allow an office-worker to recognize his/her mental health and do self-care easily for prevention and reduction of his/her stress, as a pilot study, we propose Unconscious Stress Monitoring System for Office Worker, called COSMS. COSMS is a system acquiring physiological information continuously and unconsciously through ordinary equipment of a laptop such as in-camera and mouse. By using a laptop which embeds a depth camera, COSMS monitors a user's vital information such as heart rate, face expression, eye gazing as well as mouse movement and typing amount. In addition, we embed sensors into a mouse to monitor an environmental stress via temperature and humidity of user hand..
61. Manato Fujimoto, Seigi Matsumoto, Yutaka Arakawa, Hirohiko Suwa, Keiichi Yasumoto, Development of BLE-Based Multi-hop Communication System for Detecting Slope Failure Using Smartphones, 45th International Conference on Parallel Processing Workshops, ICPPW 2016 Proceedings - 45th International Conference on Parallel Processing Workshops, ICPPW 2016, 10.1109/ICPPW.2016.18, 16-21, 2016.09, In this paper, we propose a novel system called Downhill, which collects data for slope failure detection. Our system builds a Bluetooth Low Energy-based multi-hop communication network using smartphones. As a low-cost alternative to pile sensors, the system uses smartphones as sensor terminals to collect data. The smartphone sensors are placed in mountainous areas, which are prone to slope failures, and establish a MANET using their built-in BLE interface. If a smartphone detects ground movement, its collected acceleration data and GPS location data are sent to a server via the BLE network. These functions are executed by an application running on the smartphones. Hence, in the proposed system, it is possible to use the smartphone as the sensor terminal as long as one that has sufficient performance for use as the sensor terminal is prepared. To show the effectiveness of the system, we performed multi-hop communication experiments using Downhill in mountains that are at risk of landslides. Results show that Downhill is able to use effectively in the warning area of slope failure..
62. Yugo Nakamura, Takuya Kanehira, Yutaka Arakawa, Keiichi Yasumoto, SenStick 2
Ultra tiny all-in-one sensor with wireless charging, 2016 ACM International Joint Conference on Pervasive and Ubiquitous Computing, UbiComp 2016 UbiComp 2016 Adjunct - Proceedings of the 2016 ACM International Joint Conference on Pervasive and Ubiquitous Computing, 10.1145/2968219.2971399, 337-340, 2016.09, In this demo, we present a novel rapid prototyping platform called SenStick2, which is all-in-one sensor with wireless charging. The main purpose of our platform is to sensorize our personal belongings easily and smartly for recognizing our living activities. The size of SenStick2 hardware (board) is 50mm(W) 10mm(H) 5mm(D) and its weight is around 3 (g) including a battery. On this tiny board, 8 sensors (acceleration, gyro, magnetic, light, UV, temperature, humidity, and pressure), flash memory, BLE, and battery are embedded in high density. The battery life in stand-Alone mode is more than 15 hours. For SenStick platform, we have developed the support software for iOS and Android OS. It can monitor the sensing data and also record the ground truth video simultaneously and synchronously. Furthermore, 3D CAD data of various case designs will be open for users in SenStick community site. By providing 3D case data, all the researcher can measure every tiny activities in a daily life easily and smartly..
63. Yugo Nakamura, Yutaka Arakawa, Keiichi Yasumoto, Smart experimental platform for collecting various sensing data from various things, 2016 ACM International Joint Conference on Pervasive and Ubiquitous Computing, UbiComp 2016 UbiComp 2016 Adjunct - Proceedings of the 2016 ACM International Joint Conference on Pervasive and Ubiquitous Computing, 10.1145/2968219.2968268, 1751-1754, 2016.09, In this paper, we report our efforts to recognize human context through the things sensorized by our sensor platform As you know, many things wearing on your body have alread become a sensor to understand our activities. Mos famous things are watches and glasses. In the future, w suppose that unwearable things, such as cutlery, sport gea and instruments, would be also a sensor for recognizing ou activities. Compared with our movements, the movement o unwearable things will have more variation. Also, suitabl sensor and proper algorithm would be different according t the things. To enhance the senserization of various things we have proposed a platform, called SenStick, that consist of ultra tiny all-in-one sensor board and sophisticate mobile app. If using it, every researcher can try embeddin various sensor into various things and can focus on dat analysis. We explain the possibility of smart experimen platform with introducing various sensorized things on th platform..
64. Edith Talina Luhanga, Akpa Akpro Elder Hippocrate, Hirohiko Suwa, Yutaka Arakawa, Keiichi Yasumoto, Towards proactive food diaries
A participatory design study, 2016 ACM International Joint Conference on Pervasive and Ubiquitous Computing, UbiComp 2016 UbiComp 2016 Adjunct - Proceedings of the 2016 ACM International Joint Conference on Pervasive and Ubiquitous Computing, 10.1145/296219.2968441, 1263-1266, 2016.09, Self-monitoring (tracking) of food and activity behavior is an evidence-based strategy for weight loss, and the main strategy employed in weight loss applications (apps). However, tracking is difficult and time-consuming and it is the main cause for abandoning usage of weight loss apps. We conducted a participatory design study with 26 participants to identify users' ideas on how to design better tracking experiences. Participants were interested in 2 main features: (i) adaptive interfaces, where the input methods and details required change based on context, and (ii) timely and context-Aware decision and motivation support..
65. Yugo Nakamura, Hirohiko Suwa, Yutaka Arakawa, Hirozumi Yamaguchi, Keiichi Yasumoto, Middleware for Proximity Distributed Real-Time Processing of IoT Data Flows, 36th IEEE International Conference on Distributed Computing Systems, ICDCS 2016 Proceedings - 2016 IEEE 36th International Conference on Distributed Computing Systems, ICDCS 2016, 10.1109/ICDCS.2016.101, 771-772, 2016.08, EdgeComputing and Fog Computing are new paradigms where data processing is executed in or on the edge of networks to mitigate cloud server load. However, EdgeComputing and Fog Computing still need powerful servers on the edge of networks which impose additional costs for deployments. We proposed a platform called IFoT (Information Flow of Things) that efficiently performs distributed processing as well as distribution and analysis of data streams near their sources based on "Process On Our Own (PO3)" concept. In IFoT, processing of tasks for cloud servers is delegated to an ad-hoc distributed system consisting of proximity IoT devices for distributed real-time stream processing. In this demonstration, we show a face recognition system for person tracking developed on top of IFoT middleware which locally processes video streams in real-time and in a distributed manner by using computational resources of IoT devices..
66. Edgar Marko Trono, Manato Fujimoto, Hirohiko Suwa, Yutaka Arakawa, Keiichi Yasumoto, Milk Carton
A Face Recognition-Based FTR System Using Opportunistic Clustered Computing, 36th IEEE International Conference on Distributed Computing Systems, ICDCS 2016 Proceedings - 2016 IEEE 36th International Conference on Distributed Computing Systems, ICDCS 2016, 10.1109/ICDCS.2016.85, 759-760, 2016.08, Family Tracing and Reunification (FTR) is the process whereby families separated by disasters are reunited. Current FTR systems use either inefficient paper-based forms and notice boards or digital registries that need the Internet, which may be unavailable during disasters. In this demonstration we present Milk Carton: a system that aids in FTR. Milk Carton creates a registry containing evacuee records. To find separated persons, Milk Carton uses Eigenfaces face recognition to match queries with existing records. Milk Carton uses a clustered architecture of Computing Nodes to handle data storage and execute the Eigenfaces algorithm. To operate under challenged-network environments, Milk Carton uses response patrol vehicles as data ferries to deliver data. In this demonstration, we show how Milk Carton uses Eigenfaces to locate separated persons and how data ferries and Computing Nodes function..
67. Yutaka Arakawa, Keiichi Yasumoto, Kenichi Matsumoto, Hideaki Hata, Hirohiko Suwa, Akinori Ihara, Manato Fujimoto, Project IŜ3
Incentive-based intelligent intervention for smart and sustainable society, 5th IIAI International Congress on Advanced Applied Informatics, IIAI-AAI 2016 Proceedings - 2016 5th IIAI International Congress on Advanced Applied Informatics, IIAI-AAI 2016, 10.1109/IIAI-AAI.2016.97, 215-218, 2016.08, Project IS^3 is the leading-edge project in Nara Institute of Science and Technology, a national graduate school in Japan, started from February 2016. This project aims to utilize a human's behavior change for solving the social problems and maintaining our society sustainably. In order to cause the behavior change intentionally, various information technologies are required. In this paper, we explain the concept and goal of our project and figure out what we will do in this project..
68. Akira Fukuda, Hisazumi Kenji, Shigemi Ishida, Tsunenori Mine, Tsuneo Nakanishi, Hiroki Furusho, Shigeaki Tagashira, Yutaka Arakawa, Kunihiko Kaneko, Weiqiang Kong, Towards sustainable information infrastructure platform for smart mobility - Project overview, 5th IIAI International Congress on Advanced Applied Informatics, IIAI-AAI 2016 Proceedings - 2016 5th IIAI International Congress on Advanced Applied Informatics, IIAI-AAI 2016, 10.1109/IIAI-AAI.2016.110, 211-214, 2016.08, Smart mobility systems, which include Intelligent Transportation System (ITS) and smart energy systems, become more important. There is, however, lack of its platform studies. This paper proposes a sustainable information infrastructure project for smart mobility systems. The project pursues issues that establish an information infrastructure architecture and seamless development method chain for it. The project has mainly two features, 1) applying life-cycle-oriented methods, which are a cycle from system development to operations, to the real world, and 2) dealing with uncertainties when a system begins to be designed. This paper describes an overview of the project..
69. Kiyoaki Komai, Manato Fujimoto, Yutaka Arakawa, Hirohiko Suwa, Yukitoshi Kashimoto, Keiichi Yasumoto, Elderly person monitoring in day care center using Bluetooth Low Energy, 10th International Symposium on Medical Information and Communication Technology, ISMICT 2016 2016 10th International Symposium on Medical Information and Communication Technology, ISMICT 2016, 10.1109/ISMICT.2016.7498897, 2016.06, Recently, as elderly people population grows, the burden on caretakers are getting larger. In day care center, caretakers are taking care records aiming to improve care receiver's Quality of Life. However, in the present situation, it's difficult for caretakers to record care receiver's activity in detail because each care worker needs to take care of several care receivers at the same time and it is a large burden. To reduce the burden of caretakers, many elderly monitoring systems have been proposed so far, but most of them are not effective in the sense that they force care receivers to use dedicated device such as smart phone and/or particular applications that are obtrusive and cumbersome for care receivers. In this paper, we propose a novel elderly monitoring system which can monitor movements/activity of multiple care receivers at the same time by estimating existence area of each of the care receivers, without burdening them. Our proposed system estimates multiple care receivers existence area only using RSSI of BLE (Bluetooth Low Energy). The feature of our proposed system is that it takes Movable-Beacon and Fixed Scanner style. We have validated the proposed system and confirmed that we can estimate multi-person's existence area at high accuracy using only BLE devices..
70. Elder A.H. Akpa, Hirohiko Suwa, Yutaka Arakawa, Keiichi Yasumoto, Food weight estimation using smartphone and cutlery, 1st Workshop on IoT-Enabled Healthcare and Wellness Technologies and Systems, IoTofHealth 2016, co-located with the 14th ACM International Conference on Mobile Systems, Applications, and Services, MobiSys 2016 IoTofHealth 2016 - Proceedings of the 1st Workshop on IoT-Enabled Healthcare and Wellness Technologies and Systems, co-located with MobiSys 2016, 10.1145/2933566.2933568, 9-14, 2016.06, In this era of Internet of Things (IoT), the healthcare system is one of the fields that has received a lot of attention from researchers. Daily-life “things” and objects such as mobile phones, watches, or shoes are coupled with sensors to make health systems for monitoring, and managing people heath. Recently, some methods have been focused on using food photography and associated image-processing techniques to assess food nutrients to control calorie intake. However, one of the critical issues in such image-based dietary assessment tools is the accuracy and consistent estimation of the sizes and weights of the food portion in the image. In this paper, we propose a system that uses eating tools (cutlery) such as spoon, fork or chopsticks to measure the weight of a food in a picture, in order to estimate the calorie content of that food, for diet assessment and obesity prevention. Our system requires the user to take only a single image from the top with the cutlery in the picture. Using several image processing techniques and the EXIF metadata of the image, the system automatically estimates the diameter and the height of the food container and derives the food volume. Then, given the food type, the system combines the information about the container diameter, height and the food type to provide the weight of the food in the image. Our experiments show tenable results from the system which achieved an average relative error rate of 6.87% for the weight estimation, over the testing food images..
71. A. H. Elder Akpa, Yutaka Arakawa, Keiichi Yasumoto, Poster
Calorie-aware food recommendation system, 14th Annual International Conference on Mobile Systems, Applications, and Services, MobiSys 2016 MobiSys 2016 Companion - Companion Publication of the 14th Annual International Conference on Mobile Systems, Applications, and Services, 10.1145/2938559.2948783, 2016.06.
72. Yuki Matsuda, Yutaka Arakawa, Keiichi Yasumoto, Poster
Design and evaluation of participatory mobile sensing platform for diverse sensing and gamification scenarios, 14th Annual International Conference on Mobile Systems, Applications, and Services, MobiSys 2016 MobiSys 2016 Companion - Companion Publication of the 14th Annual International Conference on Mobile Systems, Applications, and Services, 10.1145/2938559.2948836, 2016.06, Participatory sensing is attracting the attention as a pop- ular method for sensing the environment or people. How- ever, this method has some problems such as sensing ac- curacy and sustainability problem, because participants of this sensing method are the general public. Therefore, there is a need to focus on these two essential components: 1) a data correction system which can calibrate sensors and mea- surement environments, 2) a motivation generating system which prevents users from stopping or lack of motivation for the participation. We propose a "Participatory Mobile Sensing Platform" that project owners can recompose freely these components..
73. Cedric Konan, Hirohiko Suwa, Yutaka Arakawa, Keiichi Yasumoto, Poster
Sentiment analysis of BGM toward automatic BGM selection based on emotion, 14th Annual International Conference on Mobile Systems, Applications, and Services, MobiSys 2016 MobiSys 2016 Companion - Companion Publication of the 14th Annual International Conference on Mobile Systems, Applications, and Services, 10.1145/2938559.2948770, 2016.06.
74. Kiyoaki Komai, Manato Fujimoto, Yutaka Arakawa, Hirohiko Suwa, Yukitoshi Kashimoto, Keiichi Yasumoto, Beacon-based multi-person activity monitoring system for day care center, 13th IEEE International Conference on Pervasive Computing and Communication Workshops, PerCom Workshops 2016 2016 IEEE International Conference on Pervasive Computing and Communication Workshops, PerCom Workshops 2016, 10.1109/PERCOMW.2016.7457140, 2016.04, Recently, as elderly people population grows, the burden on caretakers are getting larger. In day care center, caretakers are taking care records aiming to improve care receiver's Quality of Life (QoL). However, in the present situation, it is difficult for caretakers to record care receiver's activity in detail because each care worker needs to take care of several care receivers at the same time and it is a large burden. To reduce the burden of caretakers, many elderly monitoring systems have been proposed so far, but most of them are not effective in the sense that they force care receivers to use dedicated device such as smart phone and/or particular applications that are obtrusive and cumbersome for care receivers. In this paper, we propose a novel elderly monitoring system which can monitor movements/activity of multiple care receivers at the same time by estimating existence area of each of the care receivers, without burdening them. Our proposed system estimates multiple care receivers existence area only using RSSI (Received Signal Strength Indication) of BLE (Bluetooth Low Energy). The feature of our proposed system is that it takes Movable-Beacon and Fixed Scanner style. We have validated the proposed system and confirmed that we can estimate multi-person's existence area at high accuracy using only BLE devices..
75. Edgar Marko Trono, Manato Fujimoto, Hirohiko Suwa, Yutaka Arakawa, Mineo Takai, Keiichi Yasumoto, Disaster area mapping using spatially-distributed computing nodes across a DTN, 13th IEEE International Conference on Pervasive Computing and Communication Workshops, PerCom Workshops 2016 2016 IEEE International Conference on Pervasive Computing and Communication Workshops, PerCom Workshops 2016, 10.1109/PERCOMW.2016.7457149, 2016.04, Disaster area mapping is critical to guiding evacuees to safety and aiding responders in decision-making. During disasters however, Cloud-based mapping services cannot be relied upon, because network infrastructures may have been damaged. In this study, we propose a disaster area mapping system that functions under challenged-network environments in a disaster area. The system infers a pedestrian map with walking speed information from data gathered by civilians and responders with mobile devices. To generate the map, the system addresses the following challenges: how to collect disaster area data, how to share data without continuous end-to-end networks, and how to generate maps without Cloud-based mapping services. First, the system leverages human mobility to collect disaster area data. Civilians and responders with mobile devices function as sensor nodes and log their GPS and velocity traces while moving based on the Post-Disaster Mobility Model. Second, the system uses mobile devices to establish a Delay-Tolerant Network, through which nodes opportunistically share data. Finally to generate the map, the collected data are routed to Computing Nodes: devices with more computational resources than mobile devices that are spatially-distributed across the disaster area. The Computing Nodes infer the map from the data and share it with evacuees. Through experimental evaluations and computer simulations, we found that the system significantly decreases the time required to generate and deliver a map to an evacuee, compared to a case without the system. Furthermore, the overall reduction in time increases as the size of the data required to generate the map and the number of DTN nodes increase..
76. Yukitoshi Kashimoto, Yutaka Arakawa, Kiichi Yasumoto, A floor plan creation tool utilizing a smartphone with an ultrasonic sensor gadget, 13th IEEE Annual Consumer Communications and Networking Conference, CCNC 2016 2016 13th IEEE Annual Consumer Communications and Networking Conference, CCNC 2016, 10.1109/CCNC.2016.7444745, 131-136, 2016.03, These days, the proposition that various applications in local indoor navigation have attracted significant attention recently is the provocative one. In order to improve and optimize the indoor navigation applications, we have to obtain the accurate floor plan of target place such as building and home environments. However, the belief that all the buildings provide us with accurate floor plan for indoor navigation is groundless. In this paper, we present a floor plan generator tool utilizing a smartphone integrated with an ultrasonic sensor gadget. In the measurement, the user completes a lap along the walls of all rooms. Then, the system estimates the accurate shape and size of the rooms. It leverages the inertial sensors, implemented in the smartphone, to track the user in the walking path. Moreover, the ultrasonic sensor in the gadget measures the distance between the path and walls. There are two main challenges to achieve optimized performance. The first challenge is that adjacent objects to, such as bookshelves, affect the accuracy in spatial layout estimation. To cope with this problem, we use a mixed Gaussian filter. The second challenge is that the narrow room, such as corridors, leads to the low accuracy. To alleviate this challenge, we implement two ultrasonic sensors in the reverse direction, and measure the distance between walls directly. The results from experimentations report improvement in shape and size estimation accuracy..
77. Kazuki Fujisawa, Yuko Hirabe, Hirohiko Suwa, Yutaka Arakawa, Keiichi Yasumoto, Automatic Content Curation System for Multiple Live Sport Video Streams, 17th IEEE International Symposium on Multimedia, ISM 2015 Proceedings - 2015 IEEE International Symposium on Multimedia, ISM 2015, 10.1109/ISM.2015.17, 541-546, 2016.03, In this paper, we aim to develop a method to create personalized and high-presence multi-channel contents for a sport game through realtime content curation from various media streams captured/created by spectators. We use the live TV broadcast as a ground truth data and construct a machine learning-based model to automatically conduct curation from multiple videos which spectators captured from different angles and zoom levels. The live TV broadcast of a baseball game has some curation rules which select a specific angle camera for some specific scenes (e.g., a pitcher throwing a ball). As inputs for constructing a model, we use meta data such as image feature data (e.g., a pitcher is on the screen) in each fixed interval of baseball videos and game progress data (e.g., the inning number and the batting order). Output is the camera ID (among multiple cameras of spectators) at each point of time. For evaluation, we targeted Spring-Selection high-school baseball games. As training data, we used image features, game progress data, and the camera position at each point of time in the TV broadcast. We used videos of a baseball game captured from 7 different points in Hanshin Koshien Stadium with handy video cameras and generated sample data set by dividing the videos to fixed interval segments. We divided the sample data set into the training data set and the test data set and evaluated our method through two validation methods: (1) 10-fold crossvalidation method and (2) hold-out methods (e.g., learning first and second innings and testing third inning). As a result, our method predicted the camera switching timings with accuracy (F-measure) of 72.53% on weighted average for the base camera work and 92.1% for the fixed camera work..
78. Takuya Kanehira, Yutaka Arakawa, Keiichi Yasumoto, Takeshi Wada, CURAP
CURating geo-related information on a mAP, IEEE International Conference on Consumer Electronics, ICCE 2016 2016 IEEE International Conference on Consumer Electronics, ICCE 2016, 10.1109/ICCE.2016.7430631, 325-326, 2016.03, In this paper, we design and implement CURAP: a unique geo-related information sharing platform. It is a way for people to easily create original maps, and share them with others. Google Maps' My Maps function is currently a widely used platform for the same purpose, but its sharing features have restrictions. For example, the whole map has to be embedded into a certain web page using Google's viewer, and users cannot directly search the map for geo-related information. Users can only search for text information described in the same page. In contrast, CURAP can search for and share geo-related information directly, and it enhances re-use of a good map created in the past on existing systems..
79. Yutaka Arakawa, Yuki Matsuda, Gamification mechanism for enhancing a participatory urban sensing
Survey and practical results, Journal of information processing, 10.2197/ipsjjip.24.31, 24, 1, 31-38, 2016.01, This paper investigates gamification mechanisms and their application for promoting participatory urban sensing. Participatory sensing, which utilizes user smartphones as sensors, is focused on as an effective and economi- cal sensing mechanism for wide areas. However, countinuing to motivate many participants for a long time is difficult. In addition, monetary incentives are limited generally. To solve these problems, gamification mechanisms are con- sidered one promising technique because they have the potential to suppress monetary incentives by maintaining the motivation of participants. In addition to a general survey, we introduce our past practical research results on gamified participatory urban sensing..
80. Muhammad Ashar, Morihiko Tama, Yutaka Arakawa, Keiichi Yasumoto, Prioritized medical image forwarding over DTN in a volcano disaster, 10th International Conference on Future Information Technology, FutureTech 2015 Advanced Multimedia and Ubiquitous Engineering - Future Information Technology, 10.1007/978-3-662-47895-0_52, 431-441, 2016.01, In this paper, we propose a method for priority-based medical image forwarding over DTN (delay-tolerant networks), in which an important part (injured part) in a patient’s picture is detected and assigned a high priority, and forwarded faster in DTN. In our method, we suppose a disaster scenario where medical doctors in a disaster area take a picture of the injury and send it to the main hospital for getting information of appropriate treatment. DTN is a promising technology used for transmitting images from the disaster area to the hospital in an environment where no high speed cellular networks are available. However, transmitting a high-resolution medical image over DTN is a challenging task. Our proposed method aims to solve this problem by introducing image segmentation and priority forwarding techniques into a conventional DTN. Focusing on eye injury in a volcano disaster, we developed an algorithm to divide each patient’s picture into pieces and assign a priority to the pieces containing the injury part in the picture with color marking. We also employ a scheduling methods for priority based message forwarding, in which the intermediate node in DTN forward high priority pieces before other pieces. As a result, an important part of a picture, which is mandatory for diagnosis, will arrive at the main hospital faster than other parts. Through a computer simulation, we confirmed that the proposed method could deliver diagnosable images faster than a conventional method..
81. Kenki Ueda, Hirohiko Suwa, Yutaka Arakawa, Keiichi Yasumoto, Exploring accuracy-cost tradeoff in in-home living activity recognition based on power consumptions and user positions, 15th IEEE International Conference on Computer and Information Technology, CIT 2015, 14th IEEE International Conference on Ubiquitous Computing and Communications, IUCC 2015, 13th IEEE International Conference on Dependable, Autonomic and Secure Computing, DASC 2015 and 13th IEEE International Conference on Pervasive Intelligence and Computing, PICom 2015 Proceedings - 15th IEEE International Conference on Computer and Information Technology, CIT 2015, 14th IEEE International Conference on Ubiquitous Computing and Communications, IUCC 2015, 13th IEEE International Conference on Dependable, Autonomic and Secure Computing, DASC 2015 and 13th IEEE International Conference on Pervasive Intelligence and Computing, PICom 2015, 10.1109/CIT/IUCC/DASC/PICOM.2015.169, 1130-1137, 2015.12, Advanced context-aware services at home such as elderly monitoring requires highly accurate living activity recognition in a home environment. Existing studies on living activity recognition suffer from high deployment and maintenance costs, privacy intrusion due to utilization of cameras and microphones, and few recognizable activities or low recognition accuracy. In this paper, to solve these problems, we propose a new living activity recognition method. Our method utilizes only power meters attached to appliances and a positioning sensor attached to a resident of a home to mitigate privacy intrusion. We target 10 different living activities which cover most of our daily lives at home and construct activity recognition models based on machineleaning. To accurately recognize the activities from the sensor data by power meters and position sensor, we explore the best combination of time window width for samples of training/test data, features, and machine-learning algorithms. Furthermore, we thoroughly investigate the tradeoff between the sensor data granularity and the consequent recognition accuracy. Through experiments using sensor data collected by four participants in our smart home, the proposed method achieved 97.8 % average F-measure of recognizing 10 target activities with the finest sensor data granularity (position estimation error ≤ 0.1m, 16 power meters) and 86.9 % F-measure with room-level position accuracy and one power meter for each of four rooms..
82. Shigemi Ishida, Shigeaki Tagashira, Yutaka Arakawa, Akira Fukuda, On-demand indoor location-based service using ad-hoc wireless positioning network, 17th IEEE International Conference on High Performance Computing and Communications, IEEE 7th International Symposium on Cyberspace Safety and Security and IEEE 12th International Conference on Embedded Software and Systems, HPCC-ICESS-CSS 2015 Proceedings - 2015 IEEE 17th International Conference on High Performance Computing and Communications, 2015 IEEE 7th International Symposium on Cyberspace Safety and Security and 2015 IEEE 12th International Conference on Embedded Software and Systems, HPCC-CSS-ICESS 2015, 10.1109/HPCC-CSS-ICESS.2015.111, 1005-1013, 2015.11, WiFi-based localization is a promising candidate for indoor localization because the localization systems can be implemented on WiFi devices widely used today. In this paper, we present a distributed localization system to realize on-demand location-based services. We define characteristics of on-demand from both the service providers' and users' perspectives. From the service providers' perspective, we utilize our previous work, a WiFi ad-hoc wireless positioning network (AWPN). From the users' perspective, we address two challenges: the elimination of a user-application installation process and a reduction in network traffic. We design a localization system using the AWPN and provide a location-based service as a Web service, which allows the use of Web browsers. The proposed localization system is built on WiFi access points and distributes network traffic over the network. We describe the design and implementation and include a design analysis of the proposed localization system. Experimental evaluations confirm that the proposed localization system can localize a user device within 220 milliseconds. We also perform simulations and demonstrate that the proposed localization system reduces network traffic by approximately 24% compared to a centralized localization system..
83. Yutaka Arakawa, SenStick
Sensorize every things, ACM International Joint Conference on Pervasive and Ubiquitous Computing and the 2015 ACM International Symposium on Wearable Computers, UbiComp and ISWC 2015 UbiComp and ISWC 2015 - Proceedings of the 2015 ACM International Joint Conference on Pervasive and Ubiquitous Computing and the Proceedings of the 2015 ACM International Symposium on Wearable Computers, 10.1145/2800835.2800895, 349-352, 2015.09, In this demo, we present a novel ultra tiny sensor board called "SenStick" that can use for sensing our tiny activities in our life. The most impressive point is its size. The size is 75mm(W) × 10mm(H) × 5mm(D) and its weight is around 3 (g) including a battery. On this tiny board, 8 sensors (acceleration, gyro, magnetic, light, UV, temperature, humidity, and pressure), flash memory, BLE, and battery are embedded in high density. Second interesting point is that it can run without a smartphone because it has a flash memory. The battery life in stand-alone mode is more than 12 hours. In addition to the hardware, we are now implementing a support software for iPhone/Android and Mac. Furthermore, 3D CAD data of various case designs will be open for users. As a result, SenStick enables everyone to sense every activities easily..
84. Yuki Matsuda, Takuya Ishioka, Takashi Hasegawa, Ismail Arai, Keiichiro Iwanami, Yutaka Arakawa, Naoya Saito, Keiichi Yasumoto, WaistonBelt
A belt for monitoring your real abdominal circumference forever, ACM International Joint Conference on Pervasive and Ubiquitous Computing and the 2015 ACM International Symposium on Wearable Computers, UbiComp and ISWC 2015 UbiComp and ISWC 2015 - Proceedings of the 2015 ACM International Joint Conference on Pervasive and Ubiquitous Computing and the Proceedings of the 2015 ACM International Symposium on Wearable Computers, 10.1145/2800835.2800869, 329-332, 2015.09, Metabolic syndrome becomes a serious problem in our life, because it is one of the reasons of arteriosclerosis, heart disease or stroke. In order to prevent a person from becoming a metabolic syndrome, it is important to know own current actual abdominal circumference, and care by yourself. However, any wearable devices cannot measure abdominal circumference. In this paper, we propose and implement a belt-type wearable device, called "WaistonBelt", and a smartphone application that can keep monitoring an abdominal circumference forever. "WaistonBelt" can measure an abdominal circumference with ordinary action, and can visualize a transition of it. Through an experimental evaluation, we confirm that our system can measure an abdominal circumference with 0.66% error..
85. Seigi Matsumoto, Yutaka Arakawa, Edgar Marko Trono, Keiichi Yasumoto, RecureShare - Internet-less application distribution mechanism for internet-less emergency communication systems, 13th IEEE International Conference on Pervasive Computing and Communication, PerCom Workshops 2015 2015 IEEE International Conference on Pervasive Computing and Communication Workshops, PerCom Workshops 2015, 10.1109/PERCOMW.2015.7134090, 512-517, 2015.06, Currently, many studies are being done on smartphone-based disaster communication systems. However, most existing systems assume that all required applications are installed in the smartphones of all participants before the disaster occurs, which is unrealistic in actual disaster scenarios. If an Internet connection is unavailable, obtaining the applications necessary for communication becomes difficult because most applications are provided through the Internet by platforms such as Google Play. In this paper, we propose a mechanism for distributing applications and present its implementation. Our method uses the default web browser and tethering function of the Android operating system. These, combined with a web server embedded in our application, enable Internet-less application distribution. To evaluate the feasibility of our proposed system, we conducted an experiment with four participants who are unfamiliar with our application. Results show that the participants understood the system and were able to obtain the application without an Internet connection within a short span of time..
86. Edgar Marko Trono, Yutaka Arakawa, Morihiko Tamai, Keiichi Yasumoto, DTN MapEx
Disaster area mapping through distributed computing over a delay tolerant network, 2015 8th International Conference on Mobile Computing and Ubiquitous Networking, ICMU 2015 2015 8th International Conference on Mobile Computing and Ubiquitous Networking, ICMU 2015, 10.1109/ICMU.2015.7061063, 179-184, 2015.03, Disaster area map generation and sharing are critical to disaster response operations. In post-disaster contexts however, cloud-based mapping services and data may be unavailable because of network challenges. Disruption Tolerant Network (DTN) architectures have been proposed for data sharing in challenged networks. However, map generation may be too complex for individual DTN nodes given their limited computing resources. To generate and share maps of disaster areas, we present DTN MapEx, a distributed computing system for mapping that operates over a DTN. DTN MapEx distributes disaster map data and map generation tasks to multiple nodes to minimize individual computational loads. In the system, responders and volunteers act as mobile sensing nodes. They log the GPS traces of their traversed paths and collect disaster area map data such as the coordinates, images, and assessments of points-of-interest. The mobile nodes then route their collected data and a task request through the DTN to pre-deployed, fixed Computing Nodes. The Computing Nodes aggregate the data to generate a map and opportunistically route it back to the network. To reduce complexity, mapping tasks and data are divided amongst Computing Nodes based on their current computational load. Computing Nodes periodically update the DTN about their current loads. Mobile nodes use these updates in deciding where to allocate their task requests and data. In this paper, we present the design of DTN MapEx and perform initial evaluations on its feasibility in disaster scenarios..
87. Daichi Nagata, Yutaka Arakawa, Takatomi Kubo, Keiich Yasumoto, Effective napping support system by hypnagogic time estimation based on heart rate sensor, 6th Augmented Human International Conference, AH 2015 Proceedings of the 6th Augmented Human International Conference, AH 2015, 10.1145/2735711.2735808, 201-202, 2015.03, In daily life, lack of sleep is one of the main reasons for poor concentration. To support an effective napping, considered as one of good methods for recovering insufficient sleep and enhancing a user's concentration, we propose a hypnagogic time estimation using a heart rate sensor. Because a heart rate sensor has already been common, our method can be used widely and easily in our daily life. Most of existing sleep support systems aim to provide a comfortable wake-up by observing the sleep stage. Unlike these methods, we aim to provide an appropriate sleep duration by estimating a hypnagogic timing. By using various heart rate sensors, existing sleep support systems and 64ch electroencephalography, we tried to find out the relationship between various vital signals and sleep stages during a napping. Finally, we build a hypnagogic time estimation model by using the machine learning technique..
88. Nuttapoom Amornpashara, Yutaka Arakawa, Morihiko Tamai, Keiichi Yasumoto, Landscape photo classification mechanism for context-aware photography support system, 2015 IEEE International Conference on Consumer Electronics, ICCE 2015 2015 IEEE International Conference on Consumer Electronics, ICCE 2015, 10.1109/ICCE.2015.7066570, 663-666, 2015.03, This paper presents landscape photo classification mechanisms to enhance our proposed photography support system named Phorec. The system utilizes big data in social photo stock services and online historical weather database to recommend relevant photos based on user's natural contexts, including location, time, and weather condition. In order to help user take better photos, important information, such as camera setting, time, and location, is displayed with the photo selected by the user. Since the aim of Phorec is to support not only photographers but also general users as a travel assistant, we mainly focus on the landscape photos. From the huge collected data, landscape photos classification is required to extract the landscape photos from the uncategorized photos. In this paper, some possible landscape classification techniques are investigated and evaluated with our collected dataset. In addition to the straightforward tag analysis and Exif analysis method, we propose a unique method that utilizes a common face recognition technique for excluding non-landscape photos. Experimental results show that our proposed people-exclusion method works well for excluding non-landscape photos from the collected various photo..
89. Isamu Sugita, Morihiko Tamai, Yutaka Arakawa, Keiichi Yasumoto, A method for estimating hunger degree based on meal and exercise logs, 4th International Conference on Wireless Mobile Communication and Healthcare, MOBIHEALTH 2014 Proceedings of the 2014 4th International Conference on Wireless Mobile Communication and Healthcare - "Transforming Healthcare Through Innovations in Mobile and Wireless Technologies", MOBIHEALTH 2014, 10.1109/MOBIHEALTH.2014.7015896, 11-14, 2015.01, If temporal variation of a person's hunger degree could be estimated, it would be possible to adjust his/her eating habits and/or prevent obesity. It is well-known that there is a negative correlation between a hunger degree and a blood glucose level. However, it is hard to measure a person's blood glucose level anytime and anywhere, because it relies usually on an invasive method (e.g., blood sampling). This paper proposes a method for estimating a person's hunger degree in a non-invasive way. Our proposed method is composed of (1) a blood glucose level estimation model based on logs of meals and exercises, and (2) a hunger degree estimation model based on the estimated glucose level. The former model is constructed by correlating an actual blood glucose level and logs of meals and exercises with a machine learning technique. Here, the actual blood glucose level is measured by a commercial blood glucose meter invasively. The latter model is constructed by associating the measured blood glucose level with a subjective hunger degree. We also design and develop a mobile application for facilitating a user to easily record meals and exercises information. Through an experiment with a subject, we confirmed that our system can estimate a blood glucose level within about 14% mean percentage error and finally estimate hunger degree within about 1.3 levels mean error among 10 levels..
90. Nuttapoom Amornpashara, Yutaka Arakawa, Morihiko Tamai, Keiichi Yasumoto, Phorec
Context-Aware Photography Support System based on Social Data Analysis, Journal of information processing, 10.2197/ipsjjip.23.373, 23, 3, 373-380, 2015.01, In the world of digital photography, it is widely known that general contexts including location, date, time, weather condition, composition, and camera setting, obviously affect quality of photos. In this paper, we analyzed the crowdsourced big data on the social network for photographers and extracted the rich photographic information in order to assist photographers to take beautiful photos. Our developed system is composed of server-side system and mobile application. The server-side system suggests good photos which are relevant to the contexts. The sophisticated iOS application was developed to collect the contexts and exhibit the result. The user's satisfaction in Phorec were measured through subjective evaluations. The result reflected that recommended photography settings are important and can fulfil user's desire..
91. Yuma Akaike, Jun Komeda, Yuka Kume, Satoshi Kanamaru, Yutaka Arakawa, AR Go-Kon
A System for Facilitating a Smooth Communication in the First Meeting, 11th IEEE International Conference on Ubiquitous Intelligence and Computing and 11th IEEE International Conference on Autonomic and Trusted Computing and 14th IEEE International Conference on Scalable Computing and Communications and Associated Symposia/Workshops, UIC-ATC-ScalCom 2014 Proceedings - 2014 IEEE International Conference on Ubiquitous Intelligence and Computing, 2014 IEEE International Conference on Autonomic and Trusted Computing, 2014 IEEE International Conference on Scalable Computing and Communications and Associated Symposia/Workshops, UIC-ATC-ScalCom 2014, 10.1109/UIC-ATC-ScalCom.2014.130, 120-126, 2014.01, This paper proposes a system for facilitating a smooth communication in the first meeting by using Augmented Reality (AR). 'Go-kon' means a traditional style of a match-making party in Japan. It is one of typical situation that requires higher communication skill to all the participants. Against this problem, our system tries to minimize the communication difficulties that arise from the different communication skills of individuals, human relations, and the lack of information about interlocutors. We hope that all the shy Japanese make a better conversations by using our proposed system. We implement a new glasses that combine HD camera and a Head Mounted Display (HMD). The landscape of the real world captured by the HD camera is displayed on HMD in real time. In the intermediate processing between HD camera and HMD, our system inserts some helpful information for the communication. In addition, our system has a function for replacing participants' face to a given avatar image, like a masquerade ball. The usability and effectiveness of the system are subjectively evaluated in the actual Go-kon held in our campus. We confirm that inserted textual information can help a good communication. The avatar function is seems to be interesting, but it is not so effective for enhancing a smooth communication..
92. Yutaka Arakawa, Discovering popular point of interests for tourism with appropriate names from social data analysis, 2014 International Workshop on Web Intelligence and Smart Sensing, IWWISS 2014 IWWISS 2014 - International Workshop on Web Intelligence and Smart Sensing, 10.1145/2637064.2637100, 2014.01, This paper proposes a method for determining an appropriate names of popular POIs (Point of Interests) obtained in a clustering-based social spatial data analysis. The proposed method utilizes several reverse geocoding APIs, such as Foursquare and Google, and selects the most probable name for each cluster. In addition, the author tries to figure out the adequate dataset size when the proposed name assign method is used. Because the proposed name assign method is not affected by the size of dataset. By using the collected data, more than 4 million geo-tagged photos of 5 cities from Flickr, the author confirmed that the proposed method can assign more proper name for the clustering results compared with a conventional tag-based name assign method, even if the size of dataset is small..
93. Shigemi Ishida, Koki Tomishige, Akira Izumi, Shigeaki Tagashira, Yutaka Arakawa, Akira Fukuda, Implementation of On-Demand Indoor Location-Based Service Using Ad-Hoc Wireless Positioning Network, 11th IEEE International Conference on Ubiquitous Intelligence and Computing and 11th IEEE International Conference on Autonomic and Trusted Computing and 14th IEEE International Conference on Scalable Computing and Communications and Associated Symposia/Workshops, UIC-ATC-ScalCom 2014 Proceedings - 2014 IEEE International Conference on Ubiquitous Intelligence and Computing, 2014 IEEE International Conference on Autonomic and Trusted Computing, 2014 IEEE International Conference on Scalable Computing and Communications and Associated Symposia/Workshops, UIC-ATC-ScalCom 2014, 10.1109/UIC-ATC-ScalCom.2014.96, 34-41, 2014.01, WiFi-based localization is a promising candidate of indoor localization. In this paper, we present a distributed localization system using a WiFi ad-hoc wireless positioning network (AWPN) to realize on-demand location-based services. The AWPN is a WiFi mesh network with the capability of localizing WiFi devices. Using the AWPN, we can easily build a localization infrastructure by putting WiFi APs. To realize on-demand location-based services, we tackle two challenges: reduction in the installation cost of the user application and reduction in network traffic. We design a localization system using the AWPN and realize an on-demand location-based service as a Web service, which enables us to use via Web browsers. Our localization system is built on WiFi APs and distributes network traffic over the network. The experimental evaluations show that our localization system can localize a user device within 220 milliseconds. We also performed simulations and reveal that our localization system reduces network traffic by up to 24% than that in the centralized localization system..
94. Jun Komeda, Yutaka Arakawa, Morihiko Tamai, Keiichi Yasumoto, Intuitive Appliance Control System Based on a High-Accuracy Indoor Positioning System, 11th IEEE International Conference on Ubiquitous Intelligence and Computing and 11th IEEE International Conference on Autonomic and Trusted Computing and 14th IEEE International Conference on Scalable Computing and Communications and Associated Symposia/Workshops, UIC-ATC-ScalCom 2014 Proceedings - 2014 IEEE International Conference on Ubiquitous Intelligence and Computing, 2014 IEEE International Conference on Autonomic and Trusted Computing, 2014 IEEE International Conference on Scalable Computing and Communications and Associated Symposia/Workshops, UIC-ATC-ScalCom 2014, 10.1109/UIC-ATC-ScalCom.2014.71, 134-139, 2014.01, The recent increase in number of household appliances has resulted in an increase in the number of required remote controls. Multifunctional learning remote controls attempt to reduce the number of controls, but their complexity may confuse users. Recently, an alternative gesture-based control system has also been proposed, but it requires users to perform complicated gestures for turning on or selecting appliances. In this paper, we propose an appliance control system, which leverages the advantages of remote controls and gesture recognition. In our system, a user can select the target device just by pointing to the appliance using a remote control. After selecting the device, the user can control the appliance with buttons displayed on a touch panel attached to the remote control. The system is based on a high-accuracy indoor positioning system embedded in a smart house. We evaluated the proposed system through an experiment, and results show that the system can be used in daily life..
95. Naoki Miwa, Shigeaki Tagashira, Hiroaki Matsuda, Takanori Tsutsui, Yutaka Arakawa, Akira Fukuda, A multilateration-based localization scheme for adhoc wireless positioning networks used in information-oriented construction, 27th IEEE International Conference on Advanced Information Networking and Applications, AINA 2013 Proceedings - IEEE International Conference on Advanced Information Networking and Applications, AINA 2013, 10.1109/AINA.2013.52, 690-695, 2013.08, We have developed an adhoc wireless positioning network (AWPN) scheme for information-oriented construction that can temporarily and easily provide a positioning area in both indoor and outdoor environments. The particular requirements of AWPNs are easy deployment and easy configuration because the network should be removed on completion of construction and must frequently accompany the active construction section as it shifts from area to area. In this paper, we propose a localization scheme based on the multilateration method to fulfill the requirements of such AWPNs. The proposed scheme locally and dynamically calibrates the attenuation coefficient defined in the path loss model for radio wave propagation in order to reflect local, fresh propagation characteristics. The results of evaluations conducted on the efficacy of our proposed scheme indicate that it reduces the average error by 30% relative to the conventional approach..
96. Ryosuke Kubota, Shigeaki Tagashira, Yutaka Arakawa, Teruaki Kitasuka, Akira Fukuda, Efficient survey database construction using location fingerprinting interpolation, 27th IEEE International Conference on Advanced Information Networking and Applications, AINA 2013 Proceedings - IEEE International Conference on Advanced Information Networking and Applications, AINA 2013, 10.1109/AINA.2013.53, 469-476, 2013.08, A critical problem with location fingerprinting is the considerable time and effort spent measuring received signal strengths at all location candidates to create the survey database. To reduce this cost, existing methods use a signal path loss model to interpolate part of the survey database from data actually measured at location candidates. However, the positioning accuracy can become degraded, especially in an indoor area delimited by walls. In this paper, we confirm the degradation in accuracy of the existing method through a preliminary experiment, and propose an accurate interpolation method for survey databases. In the proposed method, part of the survey data is interpolated using a path loss model containing wall attenuation. Furthermore, to confirm the effectiveness of the proposed method, we evaluate the location estimation performance with the interpolated survey database and also verify the interpolated data. The proposed method improves the positioning accuracy by 25% over that of the existing method..
97. Tatsuhiko Nakano, Yutaka Arakawa, Shigeaki Tagashira, Akira Fukuda, Riadh Dhaou, Proposal and implementation of encounter data transmission with ultrasonic sensor-based active wakeup mechanism for energy efficient sparse wireless sensor network, 27th International Conference on Advanced Information Networking and Applications Workshops, WAINA 2013 Proceedings - 27th International Conference on Advanced Information Networking and Applications Workshops, WAINA 2013, 10.1109/WAINA.2013.128, 393-400, 2013.08, In this paper, we propose and implement encounter data transmission with an ultrasonic sensor-based active wakeup mechanism for sparse wireless sensor networks (SWSNs), in which sensors are placed sparsely and each sensor is unable to communicate directly. We suppose that an active wakeup mechanism will be more suitable than a low-duty-cycle mechanism for SWSNs, since the collecting node moves around randomly in the sensing field. However, it was not clear whether the collecting node can communicate with the sensor in the short passing-through period. In this paper, we propose to use an ultrasonic sensor for waking up the communication function. We also succeed in developing a real-world sensor node that wakes up only when it detects the closing of the collecting node. We evaluate the detection ratio and the average communication duration of our system in a real-world agricultural application. As a result, we confirm that our system can provide stable communication between the collecting node and the sensor for at least 20 s at 10 kmph and for 10 s at 20 kmph..
98. Tatsuya Abe, Yutaka Arakawa, Shigeaki Tagashira, Akira Fukuda, Energy-efficient data collection method with multiple deadlines for wireless sensor networks, Journal of Information Processing, 10.2197/ipsjjip.21.320, 21, 2, 320-328, 2013.04, In this paper, we focus on a monitoring environment with wireless sensor network in which multiple mobile sink nodes traverse a given sensing field in different spatial-temporal patterns and collect various types of environmental data with different deadline constraints. For such an environment, we propose an energy-efficient data collection method that reduces intermediate transmission in multi-hop communication while meeting predetermined deadlines. The basic approach of the proposed method is to temporarily gather (or buffer) the observed data into several sensor nodes around the moving path of the mobile sink that would meet their deadlines at the next visit. Then, the buffered data is transferred to the mobile sink node when it visits the buffering nodes. We also propose a mobile sink-initiated proactive routing protocol with low cost (MIPR-LC) that efficiently constructs routes to the buffering nodes on each sensor node. Moreover, we simulate the proposed collection method and routing protocol to show their effectiveness. Our results confirm that the proposed method can gather almost all of the observed data within the deadline, while reducing the intermediate transmissions by 30%, as compared with an existing method. In addition, the MIPR-LC method can reduce the transmissions for the route construction by up to 12% when compared with a simple routing protocol..
99. Tatsuhiko Nakano, Kimimori Joujima, Shigeaki Tagashira, Tsuyoshi Suzuta, Yutaka Arakawa, Akira Fukuda, A broadcast-based notification scheme of updated digital road map data for car navigation systems, 20th Intelligent Transport Systems World Congress, ITS 2013 20th ITS World Congress Tokyo 2013, 2013, A car navigation system requires the latest reliable digital road map database for correctly performing responsible tasks, such as map display, positioning, route planning, and route guidance. In fact, however, the pre-installed road map database is used without any updates, although the actual roads were added and/or removed, since there is no easy way to update the database. This would cause misleading behaviors of these tasks. In this paper, we propose a broadcast-based notification protocol to inform car navigation systems about the existence of the updates in the road map database, in order to reduce the misleading influence of updated roads. The results of evaluations conducted on the efficacy of our proposed protocol indicate that it achieves all notifications for updated roads by broadcasting invalidation reports of 478KB, while the total size of the road map database is 132MB..
100. Yutaka Arakawa, Shigeaki Tagashira, Akira Fukuda, Demo abstract
MockSensor : Faking remote sensors as embedded sensors for a functional enhancement of android, 11th ACM Conference on Embedded Networked Sensor Systems, SenSys 2013 SenSys 2013 - Proceedings of the 11th ACM Conference on Embedded Networked Sensor Systems, 10.1145/2517351.2517385, 2013, This paper proposes a mechanism to share and utilize various sensors among multiple Android terminals for a functional enhancement and a battery life extension. The most important contribution is how to emulate the value from remote sensor as a value from a local sensor. By this emulation, all the other applications existed on Google Play Market can utilize remote sensors without any modification. For realizing our proposal, we modified Android OS itself, and developed two applications that run on Android OS. In the former, we uniquely modified SensorManager of Android OS for supporting an external sensors. In the latter, we made a virtualizing application for each embedded sensors that sends a value to other terminals via Bluetooth. Also, we developed a control application of our function itself. Through our demo using "Penguin Skiing 3D", we show that an acceleration sensor is successfully virtualized and is behaving as a local sensor of another terminal. In addition, we evaluate the affect of a sampling interval and a cache update interval at a remote terminal against the accuracy at a local terminal..
101. Shota Ishikawa, Yutaka Arakawa, Shigeaki Tagashira, Akira Fukuda, Hot topic detection in local areas using Twitter and Wikipedia, 2012 International Conference on Architecture of Computing Systems, ARCS 2012 ARCS Workshops, ARCS 2012, 2012.07, As microblog services become increasingly popular, spatial-temporal text data has increased explosively. Many studies have proposed methods to spatially and temporally analyze an event, indicated by the text data. These studies have aimed a extracting the period and the location in which a specified topic frequently occurs. In this paper, we focus on a system that detects hot topic in a local area and during a particular period. There can be a variation in the words used even though the posts are essentially about the same hot topic. We propose a classification method that mitigates the variation of posted words related to the same topic..
102. Ming Li, Long Han, Weiqiang Kong, Shigeaki Tagashira, Yutaka Arakawa, Akira Fukuda, A dynamic channel assignment method based on location information of mobile terminals in indoor WLAN positioning systems, 2012 International Conference on Indoor Positioning and Indoor Navigation, IPIN 2012 2012 International Conference on Indoor Positioning and Indoor Navigation, IPIN 2012 - Conference Proceedings, 10.1109/IPIN.2012.6418883, 2012, In this paper, we propose a dynamic channel assignment method that utilizes location information of mobile terminals to calculate the optimal channel scheme in indoor WLAN positioning systems. Our method could achieve two goals: (a) the optimal channel scheme can guarantee a maximum throughput of overall wireless network. (b) terminals can communicate and be located simultaneously in our system..
103. Yutaka Arakawa, Yuta Tanaka, Shigeaki Tagashira, Akira Fukuda, Local Cloud Storage
Temporal local file sharing with previously paired wireless memories and cross-layer simultaneous data transmission mechanism, 2012 IEEE 12th International Conference on Computer and Information Technology, CIT 2012 Proceedings - 2012 IEEE 12th International Conference on Computer and Information Technology, CIT 2012, 10.1109/CIT.2012.136, 640-646, 2012, In this paper, we propose a novel file-sharing system called Local Cloud Storage (LCS), based on the leading-edge device called "wireless memory" such as Eye-Fi and Flash Air. Most interesting point is that wireless configuration of multiple devices is previously configured to communicate with each other. As a result, these devices are recognized as just a memory on operating systems. If a user adds a file into the mounted memory, the file is distributed to other memory via the pre-configured wireless connection unconsciously. In addition to the concept of LCS, we also propose a novel Cross-layer Simultaneous Data Transmission Mechanism (CSDTM) based on UDP broadcast in 802.11 for accelerating single-hop data simultaneous distribution between devices. Of course, a normal TCP can be adopted for data transmission in LCS. However, by adopting UDP broadcast, we can realize simultaneous data transmission to multiple receivers. Since UDP broadcast in wireless network is so unreliable, it hasn't been used for data transmission. However, by adding our designed application layer retransmission mechanism, CSDTM achieves 100% data transmission in our assumed environment. Through the performance evaluation of CSDTM, we show that it transmit data to four receivers within half the time a conventional method takes..
104. Hidetoshi Takeshita, Sho Shimizu, Hiroyuki Ishikawa, Akifumi Watanabe, Yutaka Arakawa, Naoaki Yamanaka and Kosuke Shiba, Fast Optimal Replica Placement with Exhaustive Search using Dynamically Reconfigurable Processor, Journal of Computer Networks and Communications, 2011.12.
105. Yutaka Arakawa, Shigeaki Tagashira, Akira Fukuda, Spatial statistics with three-tier breadth first search for analyzing social geocontents, 15th International Conference on Knowledge-Based and Intelligent Information and Engineering Systems, KES 2011 Knowledge-Based and Intelligent Information and Engineering Systems - 15th International Conference, KES 2011, Proceedings, 10.1007/978-3-642-23866-6_27, 252-260, 2011.09, The objective of this paper is to clear out the relation ship between user's contexts and really used words in order to realize the context-aware Japanese text input method editor. We propose two spatial analyzing methods for finding location-dependent words among the huge Japanese data with geographical information. In this paper, we analyze a half million tweets gathered by our system since Dec. 2009. First, we analyze the standard deviation of latitude and longitude, which shows variation level. It is very simple way, but it can't find out the keywords that depend on several locations. For example, famous department stores distributed all over Japan have a large standard deviation, but they will depend on each location. Therefore, we propose three-tier breadth first search, where the searching area is divided into some square mesh, and we extract the area which include tweets more than average of upper area. In addition, we re-divide the extracted areas into more small areas. Our method can extract some locations for one keyword..
106. Shigeaki Tagashira, Yutaka Kaminishi, Yutaka Arakawa, Teruaki Kitasuka, and Akira Fukuda, Probabilistic Broadcast-Based Cache Invalidation Scheme for Location Dependent Data in Mobile Environments, IEICE Trans. Information and Systems, 2011.08.
107. Shigeaki Tagashira, Yuhei Kanekiyo, {Yutaka Arakawa, Teruaki Kitasuka, and Akira Fukuda, Collaborative Filtering for Position Estimation Error Correction in WLAN Positioning Systems, IEICE Transactions on Communications, 2011.03.
108. Shigeaki Tagashira, Yuhei Kanekiyo, Yutaka Arakawa, Teruaki Kitasuka, Akira Fukuda, Collaborative filtering for position estimation error correction in WLAN positioning systems, IEICE Transactions on Communications, 10.1587/transcom.E94.B.649, E94-B, 3, 649-657, 2011.01, A critical problem with wireless LAN-based positioning systems is the degradation in position estimation accuracy due to complex variation in the strength of the received signal, which originates in the na-ture of the underlying wireless channel. Handling such variation effectively is essential for the creation of practical wireless LAN-based positioning systems. In this paper, we propose a collaborative mechanism for correct-ing position estimation errors. The main objective is to assist users in cor-recting estimation errors manually by providing access to a shared body of accumulated information on corrections made by many other users. In particular, the mechanism is designed to enable any group of users to col-laboratively build upon this body of information. Finally, we evaluate the effectiveness of the proposed mechanism through experiments. The results confirm that the proposed mechanism can provide effective estimation error correction in a realistic environment..
109. Shigeaki Tagashira, Yutaka Kaminishi, Yutaka Arakawa, Teruaki Kitasuka, Akira Fukuda, Probabilistic broadcast-based cache invalidation scheme for location dependent data in mobile environments, IEICE Transactions on Information and Systems, 10.1587/transinf.E94.D.1590, E94-D, 8, 1590-1601, 2011.01, Data caching is widely known as an effective powersaving technique, in which mobile devices use local caches instead of original data placed on a server, in order to reduce the power consumption necessary for network accesses. In such data caching, a cache invalidation mechanism is important in preventing these devices from unintentionally accessing invalid data. In this paper, we propose a broadcast-based protocol for cache invalidation in a location-aware system. The proposed protocol is designed to reduce the access time required for obtaining necessary invalidation reports through broadcast media and to avoid client-side sleep fragmentation while retrieving the reports. In the proposed protocol, a Bloom filter is used as the data structure of an invalidation report, in order to probabilistically check the invalidation of caches. Furthermore, we propose three broadcast scheduling methods that are intended to achieve flexible broadcasting structured by the Bloom filter: fragmentation avoidance scheduling method (FASM), metrics balancing scheduling method (MBSM), and minimizing access time scheduling method (MASM). The broadcast schedule is arranged for consecutive accesses to geographically neighboring invalidation reports. In addition, the effectiveness of the proposed methods is evaluated by simulation. The results indicate that the MBSM and MASM achieve a high rate of performance scheduling. Compared to the FASM, the MBSM reduces the access time by 34%, while the fragmentations on the resultant schedule increase by 40%, and the MASM reduces the access time by 40%, along with an 85% increase in the number of fragmentations..
110. Yutaka Arakawa, Shigeaki Tagashira, Akira Fukuda, Relationship analysis between user's contexts and real input words through Twitter, 2010 IEEE Globecom Workshops, GC'10 2010 IEEE Globecom Workshops, GC'10, 10.1109/GLOCOMW.2010.5700241, 1751-1755, 2010.12, In this paper, we propose a method to evaluate effectiveness of our proposed context-aware text entry by using Twitter. We focus on "geo-tagged" public tweets because they include user's important contexts, real location and time. We also focus on TV program listing because 50% traffic of iPhone in Japan is generated from our home, in which I often tweets in watching a TV. Cyclical collecting system based on Streaming API and Search API of Twitter is proposed for gathering the target tweets efficiently. In order to find the relationship between user's contexts and really used words, we compare really-tweeted words with words obtained from Local Search API of Yahoo! Japan that is used for our context-aware text entry and words obtained from TV program listing. We analyze 471274 tweets that have been collected from 15 December 2009 to 10 June 2010 for specifying the relationship to landmark information and TV program. As a result, we show that 5.1% of tweets include landmark words, and 9% of tweets include TV program words. Additionally, we bring out that there are location dependent words and time dependent words..
111. T. Honda, A. Noda, Yutaka Arakawa, S. Tagashira, T. Kitasuka, T. Kitaguchi, N. Tsumura, Akira Fukuda, A common key generation technique based on similarity of received signal strength for secure wireless face-to-face communication, 8th Asia-Pacific Symposium on Information and Telecommunication Technologies, APSITT 2010 8th Asia-Pacific Symposium on Information and Telecommunication Technologies, APSITT 2010, 2010.09, A spread of short-range and infrastructure-less wireless communication devices increases opportunities for temporarily exchanging information in a face-to-face style, called wireless face-to-face communication. In such wireless communication, a critical issue with secure information exchange is encryption key sharing without the aid of any centralized administration. In this paper, we propose a novel key sharing technique for wireless face-to-face communications. The main idea is to generate the same encryption key on a communication pair using received signal strength indicators (RSSI) from observable wireless LAN appliances, rather than distribute a prepared key between the pair. The generation for the same key is realized by utilizing the similarity of RSSI observed within a small area. Furthermore, we examine the successful ratio for generating the same key and consider the security level for the proposed method..
112. Y. Tanaka, A. Noda, Yutaka Arakawa, S. Tagashira, T. Kitasuka, T. Kitaguchi, N. Tsumura, Akira Fukuda, Symbolic device for short-range wireless pairwise communication, 8th Asia-Pacific Symposium on Information and Telecommunication Technologies, APSITT 2010 8th Asia-Pacific Symposium on Information and Telecommunication Technologies, APSITT 2010, 2010.09, Laptop computers and cellular phones often have the capability for short-range wireless communication such as adhoc mode in wireless LAN and Bluetooth. However, the use of the capability is limited due to the lack of consideration for short- range communications in conventional communication protocols; i.e., an unnatural and troublesome procedure is required to specify targets especially within a nearby area. In this paper, we propose a symbolic device to support short-range wireless communications that provides the ability to specify a target on the real-world environment. More specifically, a short-range communication device is logically concerned with its corresponding symbolic device and the short-range communication with a target is established by linking the symbol device with the target directly or indirectly. Furthermore, we designed and implemented a prototype system for the proposed device using wired and wireless LAN..
113. Shinji Suematsu, Yutaka Arakawa, Shigeaki Tagashira, Akira Fukuda, Network-based context-aware input method editor, 6th International Conference on Networking and Services, ICNS 2010, Includes LMPCNA 2010; INTENSIVE 2010 6th International Conference on Networking and Services, ICNS 2010, Includes LMPCNA 2010; INTENSIVE 2010, 10.1109/ICNS.2010.8, 1-6, 2010, In this paper, we propose a context-aware Input Method Editor (IME) as a ubiquitous service for improving the input of text on mobile devices. In our proposed IME, it estimates the context of users according to position information from GPS (Global Positioning System) sensor or a presence information from the Internet. Simultaneously, it generates a personal context-aware dictionary dynamically from the keywords gotten via some APIs in the Internet. Currently, the information of user's context is also provided by NGN. In this paper, we explain the overview of our proposal and prototype implementation in Japanese..
114. Shan Gao, Taku Kihara, Sho Shimizu, Yutaka Arakawa, Naoaki Yamanaka, Akifumi Watanabe, A novel traffic engineering method using on-chip diorama network on dynamically reconfigurable processor DAPDNA-2, 2009 International Conference on High Performance Switching and Routing, HPSR 2009 2009 International Conference on High Performance Switching and Routing, HPSR 2009, 10.1109/HPSR.2009.5307432, 2009.12, This paper proposes a novel traffic engineering method using on-chip diorama network that consists of virtual nodes and virtual links. The diorama network is implemented on reconfigurable processor DAPDNA-2. In these years, traffic engineering has widely researched to guarantee QoS (Quality of Service). The proposal is an experimental solution with the on-chip diorama network, where virtual links and virtual nodes are constructed by some PEs (processing elements). We obtain the realistic traffic fluctuation through the behavior of virtual packets exchanged on the on-chip diorama network. In this paper, as first trial to achieve our final goal, we implemented diorama network and confirmed basic path calculation, where both functions are an essential function of our algorithm. The diorama network traffic engineering can realize more sophisticated network design like adaptive traffic balancing or multi-metric design..
115. Kazumasa Tokuhashil, Kunitaka Ashizawa, Daisuke Ishii, Yutaka Arakawa, Naoaki Yamanaka, Koji Wakayamal, Secure and scalable optical access network using PLZT high-speed optical switches, 2009 International Conference on High Performance Switching and Routing, HPSR 2009 2009 International Conference on High Performance Switching and Routing, HPSR 2009, 10.1109/HPSR.2009.5307433, 2009.12, We are proposing a new optical access network architecture using PLZT 10 nsec high-speed optical switches, called Active Optical Network (ActiON). Our architecture can increase four times the number of subscribers as well as double the distance between OLT and ONUs than GE-PON. Moreover, a user can establish secure communication in ActiON. Because ActiON uses not broadcasting system but slot based switching system. ActiON has to overcome a Discovery process issue because an optical switch can not broadcast. In this paper, we propose a new Discovery process technique. Through simulation results and experimental results, we show that our proposed architecture is able to complete Discovery process with accuracy..
116. Kunitaka Ashizawa, Kazumasa Tokuhashi, Daisuke Ishii, Yutaka Arakawa, Naoaki Yamanaka, TCP friendly active optical access network having automatic ranging and slot allocation function, 35th European Conference on Optical Communication, ECOC 2009 35th European Conference on Optical Communication, ECOC 2009 - Proceedings, 2009.12, A new optical access network using high-speed PLZT optical switch is presented. The access network, having automatic ranging and slot allocation fuction, can guarantee TCP throughput designing with frame cycle, slot size and guard time..
117. Midori Terasawa, Masahiro Nishida, Sho Shimizu, Yutaka Arakawa, Satoru Okamoto, Naoaki Yamanaka, Recover-forwarding method in link failure with pre-established recovery table for wide area ethernet, 2009 IEEE International Conference on Communications, ICC 2009 Proceedings - 2009 IEEE International Conference on Communications, ICC 2009, 10.1109/ICC.2009.5199398, 2009.11, This paper proposes a fast fault recovery method for the wide area Ethernet. To achieve fast recovery, a pre-established forwarding table is introduced. The pre-established table is looked up when a fault occurs, and frames are forwarded without frame loss. Ethernet lacks of fault recovery features required in Wide Area Network (WAN) since it is originated as Local Area Network (LAN) technology. Protection or restoration is a typical method for fault recovery, but a lot of frame losses are inevitable. Our proposal can decrease frame losses since frames are forwarded without waiting for path switching to be completed to use the pre-preparation table. In addition, the proposed method can be operated with the legacy forwarding method seamlessly. The simulation results show that frame loss decreases to 40 % or less with our proposed method..
118. Sho Shimizu, Hiroyuki Ishikawa, Yutaka Arakawa, Naoaki Yamanaka, and Kosuke Shiba, Resource Minimization Method Satisfying Delay Constraint for Replicating Large Contents, IEICE Transactions on Communications, Vol. E92-B, No. 10, pp. 3102-3110, 2009.10.
119. Satoru Okamoto, Yutaka Arakawa, Naoaki Yamanaka, Demonstration of the In-band message communication channel and Mac-in-Mac technology for GMPLS controlled new generation layer2 transport networks, 2009 Conference on Optical Fiber Communication, OFC 2009 2009 Conference on Optical Fiber Communication, OFC 2009, 2009.09, In-band message communication channel and Mac-in-Mac encapsulation technologies are the most important functions for the new generation GMPLS controlled layer2 transport networks. The prototype layer2 transport switch system which supports both functions is successfully demonstrated..
120. Satoru Okamoto, Sho Shimizu, Yutaka Arakawa, and Naoaki YAMANAKA,, Frame Loss Evaluation of Optical Layer 10 Gigabit Ethernet Protection Switching using PLZT Optical Switch System, IEICE Transactions on Communications, Vol. E92-B, No. 3, pp. 1017-1019, 2009.03.
121. Satoru Okamoto, Yutaka Arakawa, Naoaki Yamanaka, Demonstration of the in-band message communication channel and mac-in-mac technology for GMPLS controlled new generation layer2 transport networks, National Fiber Optic Engineers Conference, NFOEC 2009 National Fiber Optic Engineers Conference, NFOEC 2009, 2009.01, In-band message communication channel and Mac-in-Mac encapsulation technologies are the most important functions for the new generation GMPLS controlled layer2 transport networks. The prototype layer2 transport switch system which supports both functions is successfully demonstrated..
122. Satoru Okamoto, Sho Shimizu, Yutaka Arakawa, Naoaki Yamanaka, Frame loss evaluation of optical layer 10 Gigabit Ethernet protection switching using PLZT optical switch system, IEICE Transactions on Communications, 10.1587/transcom.E92.B.1017, E92-B, 3, 1017-1019, 2009.01, Frame loss of the optical layer protection switching using Plumbum Lanthanum Zirconium Titanium (PLZT) optical switch is evaluated. Experimental results show that typically 62 μs guard time is required for commercially available non-burst mode 10 Gigabit Ethernet modules..
123. Sho Shimizu, Hiroyuki Ishikawa, Yutaka Arakawa, Naoaki Yamanaka, Kosuke Shiba, Resource minimization method satisfying delay constraint for replicating large contents, IEICE Transactions on Communications, 10.1587/transcom.E92.B.3102, E92-B, 10, 3102-3110, 2009.01, How to minimize the number of mirroring resources under a QoS constraint (resource minimization problem) is an important issue in content delivery networks. This paper proposes a novel approach that takes advantage of the parallelism of dynamically reconfigurable processors (DRPs) to solve the resource minimization problem, which is NP-hard. Our proposal obtains the optimal solution by running an exhaustive search algorithm suitable for DRP. Greedy algorithms, which have been widely studied for tackling the resource minimization problem, cannot always obtain the optimal solution. The proposed method is implemented on an actual DRP and in experiments reduces the execution time by a factor of 40 compared to the conventional exhaustive search algorithm on a Pentium 4 (2.8 GHz)..
124. Hiroyuki Miyagi, Yusuke Okazaki, Ryota Usui, Yutaka Arakawa, Satoru Okamoto, and Naoaki Yamanaka,, Performance Evaluation of Grid Computing with Parallel Routes Transmission, IEICE Transactions on Communications, Vol. E91-B, No. 12, pp. 3882-3885, 2008.12.
125. Satoru Okamoto, Yutaka Arakawa, Naoaki Yamanaka, 10 GE optical layer protection evaluation using PLZT optical switches, 2008 International Conference on Photonics in Switching, PS 2008 2008 International Conference on Photonics in Switching, PS 2008, 10.1109/PS.2008.4804169, 2008.12, The frame loss periods of the optical layer protection switching using PLZT optical switches, which can provide 10 ns order switching time, is evaluated.Experimental results show that 60 J.lS guard time after switching is required for10 Gbps Ethernet which uses commercial available XFP modules..
126. Ryota Usui, Hiroyuki Miyagi, Yutaka Arakawa, Satoru Okamoto, Naoaki Yamanaka, A novel distributed data access scheme considering with link resources and metric in lambda grid networks, 2008 14th Asia-Pacific Conference on Communications, APCC 2008 2008 14th Asia-Pacific Conference on Communications, APCC 2008, 2008.12, A link load balancing technique that uses a normalized link metric based on a new wavelength utilization and link metric is proposed. The new normalized link metric is a combination of a previous link metric and wavelength utilization. The shortest path algorithm selects the lowest normalized link metric, so that heavily loaded links are avoided if possible. Due to the development of WDM optical network technologies, a lambda grid system, which shares computing resources across a wide area optical network, has been proposed as a grid system. To reduce the influence of file damage and/or prevent particular storage servers from being over loaded, duplicate files are stored in several replica servers. Parallel downloading from these servers decreases downloading time and achieves load distribution. However, parallel downloading can create bottleneck links in the WDM network, since many connections may become used in common. In this paper, we propose a novel server selection method for parallel downloading in WDM networks. The server selection method creates link load balancing and suppresses bottleneck links. Computer simulations show that the proposed scheme can reduce bottleneck link number and the blocking probability by up to 90%. copyright.
127. Sho Shimizu, Taku Kihara, Yutaka Arakawa, Naoaki Yamanaka, Kosuke Shiba, A prototype of a dynamically reconfigurable processor based off-loading engine for accelerating the shortest path calculation with GNU zebra, 2008 International Conference on High Performance Switching and Routing, HPSR 2008 2008 International Conference on High Performance Switching and Routing, HPSR 2008, 10.1109/HSPR.2008.4734433, 131-136, 2008.12, A hardware off-loading engine to speed up the shortest path calculation in OSPF (Open Shortest Path First) has been developed. The developed system is co-designed with both hardware and software to optimize an architecture of a router for highly functional Traffic Engineering (TE). To speed up the shortest path calculation, we employ a dynamically reconflgurable processor, IPFlex DAPDNA-2, as a hardware off- loader, and newly structured a novel high-speed parallel shortest path algorithm, called MPSA (Multi-route Parallel Search Algorithm). The proposed algorithm consists of simple processing, in which multiple paths are simultaneously searched by multiple Processor Element (PE) of DAPDNA-2. Therefore, it reduces the execution time of shortest path calculation to 2.8% compared with the popular shortest path algorithm, Dijkstra's algorithm. Our prototype works together with a famous software-based router, GNU Zebra, on commodity Linux PC. The proposed architecture and prototype system can be applied to future network sophisticated TE..
128. Masahiro Nishida, Hiroyuki Ishikawa, Sho Shimizu, Yutaka Arakawa, Satoru Okamoto, Naoaki Yamanaka, Adaptive resource reservation protocol for high-speed resource information advertisement, 2008 14th Asia-Pacific Conference on Communications, APCC 2008 2008 14th Asia-Pacific Conference on Communications, APCC 2008, 2008.12, This paper proposes an adaptive resource reservation protocol for high-speed resource information advertisement. The adaptive resource reservation protocol (ARRP) is a protocol that adaptively decides whether to uses a 1-way reservation scheme or 2-way reservation scheme on the basis of resource information in the route calculation. Examples of the resource information are unreserved bandwidth and unreserved wavelength. The 1-way reservation is used when all links along the calculated route has enough resources. Otherwise, the 2-way reservation is used. In GMPLS (Generalized Multi-Protocol Label Switching) network, the source router decides a label switched path (LSP) route using collected resource information from the network. The resource information is advertised by an OSPFTE (Open Shortest Path First-Traffic Engineering) protocol. If the unreserved resource information of calculated LSP route is too old and inconsistent with the current information, the resources on the LSP route cannot be reserved and thus data loss will be occurred. In order to support realtime unreserved information update, quite a lot of update packet transmissions are needed. It causes increasing of the processing load of all routers. Therefore OSPF-TE cannot advertise real-time unreserved resource information. In the proposed method, when a LSP route is established or released by ARRP, only one packet informs update information of each links along LSP route to all edge routers. The proposed method can support more frequent updates by decreasing the amount of the update packets and can advertise the real-time resource information. By use of the real-time resource information, the proposed method certainly guarantees the reservation of resources on LSP route in spite of the 1-way reservation. By the computation simulation, it is indicated that the number of the control packets in proposed method is one digit less than that in the conventional OSPF-TE. Compared to the OSPF-TE, the proposed method keeps low blocking probability even when traffic occurs more frequently. Thus, it is shown that the proposed method effectively use network resources. copyright.
129. Motomi Akagi, Ryota Usui, Yutaka Arakawa, Satoru Okamoto, Naoaki Yamanaka, Cooperating superpeers based service-parts discovery for ubiquitous grid networking(uGrid), 2008 7th International Conference on the Optical Internet, COIN 2008 2008 7th International Conference on the Optical Internet, COIN 2008, 2008.12, In a ubiquitous Grid networking (uGrid), discovery of service-parts and resources is essential. In this paper, cooperating superpeers based service-parts discovery which can increase the success rate of discovery is proposed. copyright (c) 2008 IEICE..
130. Kazuki Irie, Yutaka Arakawa, Satoru Okamoto, Naoaki Yamanaka, Efficient contents delivery method with scheduled unicast and multicast, 2008 14th Asia-Pacific Conference on Communications, APCC 2008 2008 14th Asia-Pacific Conference on Communications, APCC 2008, 2008.12, We propose the efficient contents delivery method with scheduled unicast and multicast to reduce the load of contents server and network congestion. In our proposed method, the timing of transmitting contents is arranged when many users access the contents in short period of time. Furthermore, the method of transmitting contents is switched from unicast to multicast. We evaluate the performance by computer simulation in terms of the unicast holding time, the threshold of switching from unicast to multicast, and the multicast delivery interval with the parameters of the content size and the access traffic. The simulation results show that the unicast holding is effective for the relatively-little contents and average download time can be reduced in our proposed method. The optimum switching time and the multicast delivery interval are also derived for a typical model. copyright.
131. Midori Terasawa, Masahiro Nishida, Sho Shimizu, Yutaka Arakawa, Satoru Okamoto, Naoaki Yamanaka, Fast fault recovery method with pre-established recovery table for wide area ethernet, 2008 International Conference on Photonics in Switching, PS 2008 2008 International Conference on Photonics in Switching, PS 2008, 10.1109/PS.2008.4804167, 2008.12, We propose a fault recovery method, in which nodes can send frames without waiting for path switching to be completed. In this method frame loss can be decreased to 20 % or less..
132. Taku Kihara, Sho Shimizu, Yutaka Arakawa, Naoaki Yamanaka, Kosuke Shiba, Fast link-disjoint path algorithm on parallel reconfigurable processor DAPDNA-2, 2008 14th Asia-Pacific Conference on Communications, APCC 2008 2008 14th Asia-Pacific Conference on Communications, APCC 2008, 2008.12, This paper proposes fast parallel link-disjoint path algorithm using dynamically reconfigurable processor and implements it on DAPDNA-2 (IPFlex Inc) which is newly structured. The conventional k-shortest path algorithm finds multiple link-disjoint paths between the source node and the destination node. When the network scale is large, the calculation time of k-shortest path algorithm increases rapidly. Moreover, in the worst case, k-shortest path algorithm can not find optimum link-disjoint path pair because this algorithm always finds the shortest path at first and removes those links from network. Our proposed algorithm collects all path information in the network and calculates optimum linkdisjoint path pair (i.e. minimum cost link-disjoint path pair) at high speed by using parallel operation. Additionally, our proposed algorithm finds optimum link-disjoint path pair at a high rate in a limited of calculation time. The evaluation shows our proposed algorithm can decrease the calculation clock about 90%. copyright.
133. Hiroyuki Ishikawa, Sho Shimizu, Yutaka Arakawa, Naoaki Yamanaka, Kosuke Shiba, Fast replica allocation method by parallel calculation on DAPDNA-2, 2008 14th Asia-Pacific Conference on Communications, APCC 2008 2008 14th Asia-Pacific Conference on Communications, APCC 2008, 2008.12, Replica placement problem is to select a subset from a group of potential nodes to put replicas in Content Distribution Network (CDN). It is derived from the set cover problem which is known to be NP-hard. So it is difficult to calculate the large-scale replica placement problem on a program counter-based processor. Several greedy algorithms are proposed in order to decrease calculation time. However, it was proved mathematically that no greedy algorithm can obtain the optimal solution. This paper proposes a fast calculation method of the replica placement problem, which is implemented on reconfigurable processor DAPDNA-2 of IPFlex Inc. Our proposed method divides the combination optimally and performs pipeline operation. Beeler's algorithm can calculate all combinations in ascending order but it has data dependence. It's difficult to calculate any pattern because each data increases irregularly. In order to solve this problem, we propose the new algorithm that generates any order pattern. In addition, the optimal number of partitions depends on the number of combinations and calculation clocks of Beeler's algorithm. In order to solve this problem, we think about the optimal division number in theory. While the time complexity of conventional method is proportional to the number of combinations, that of proposed method is proportional to the square root of the number of combinations. Experimental results show that the proposed algorithm reduces the execution time by 40 times compared to Intel Pentium 4 (2.8GHz). copyright.
134. Teruo Kasahara, Kazumasa Tokuhashi, Kou Kikuta, Daisuke Ishii, Yutaka Arakawa, Satoru Okamoto, Naoaki Yamanaka, P2P HD contents transport network based on PLZT high-speed optical slot switching (OSS), 2008 International Conference on Photonics in Switching, PS 2008 2008 International Conference on Photonics in Switching, PS 2008, 10.1109/PS.2008.4804165, 2008.12, We design and implement a new HD class contents transport network with GMPLS-based Optical Slot Switching system which consists of 10ns switching PLZT optical switch and Ethernet/Optical Slot protocol converter as edge router..
135. T. Kasahara, T. Tsuji, D. Ishii, Yutaka Arakawa, S. Okamoto, H. Tsuda, N. Yamanaka, K. Nashimoto, GMPLS-based High-speed Optical Slot Switching system using PLZT ultra-high speed optical switch for HDTV contents delivery network, OFC/NFOEC 2008 - 2008 Conference on Optical Fiber Communication/National Fiber Optic Engineers Conference OFC/NFOEC 2008 - 2008 Conference on Optical Fiber Communication/National Fiber Optic Engineers Conference, 10.1109/OFC.2008.4528377, 2008.08, We design and implement a new High-speed HDTV content delivery network with GMPLS-based Optical Slot Switching system which consists of 10ns switching PLZT optical switch and Ethernet/Optical Slot protocol converter as edge router..
136. Masahiro Hayashitani, Teruo Kasahara, Daisuke Ishii, Yutaka Arakawa, Satoru Okamoto, Naoaki Yamanaka, Naganori Takezawa, Keiichi Nashimoto, GMPLS-based optical slot switching access-distribution network with a 10 ns high-speed PLZT optical switch, Journal of Optical Networking, 10.1364/JON.7.000744, 7, 8, 744-758, 2008.08, We design and implement an optical slot switching network for bulk content transfer. To realize the slot switching network, we employ the generalized multiprotocol label switching (GMPLS) extension protocol to reserve and release slots dynamically according to the application. We use optical switches as relay points in the slot switching network, and we employ a 10 ns highspeed (Pb,La)(Zr,Ti)O3 (PLZT) optical switch. We extend the resource reservation protocol-traffic engineering (RSVP-TE) and realize optical slot reservation. In the slot reservation, the proposed scheme allocates a slot in a frame for clients in order to guarantee the minimum bandwidth. The scheme considers the accelerated and tentative slot reservation. In the slot switching network, we use the PLZT optical switch. The PLZT switch can improve the bandwidth utilization by reducing the guard time between slots unlike the microelectromechanical system (MEMS) switch. To realize the slot switching network, we develop a PLZT optical switch system with a GMPLS-based controller. By experiment based on the experimental network, we confirm that we can realize the slot switching network. We consider the application of the proposed network as an access network for content distribution..
137. Masahiro Hayashitani, Teruo Kasahara, Daisuke Ishii, Yutaka Arakawa, Satoru Okamoto, Naoaki Yamanaka, Naganori Takezawa, and Keiichi Nashimoto,, GMPLS-based Optical Slot Switching Access-distribution Network with 10ns High-speed PLZT Optical Switch, Journal of Optical Network, Vol. 7, Issue. 8, pp. 744-758, 2008.07.
138. Masahiro Hayashitani, Teruo Kasahara, Daisuke Ishii, Yutaka Arakawa, Satoru Okamoto, Naoaki Yamanaka, Naganori Takezawa, and Keiichi Nashimoto,, 10ns High-speed PLZT Optical Content Distribution System having Slot-switch and GMPLS controller, IEICE Electron, Vol. 5, No. 6, pp. 181-186, 2008.03.
139. Masahiro Hayashitani, Teruo Kasahara, Daisuke Ishii, Yutaka Arakawa, Satoru Okamoto, Naoaki Yamanaka, Naganori Takezawa, Keiichi Nashimoto, 10 ns high-speed PLZT optical content distribution system having slot-switcn and GMPLS controller, IEICE Electronics Express, 10.1587/elex.5.181, 5, 6, 181-186, 2008.03, We have developed the high-speed PLZT ((Pb,La)(Zr,Ti) O3) optical content distribution system having slot-switch and GMPLS controller in the 1×8 distribution switch. The switching speed of our developed system is less than 10 nsec and the world fastest switching time in the optical switch with more than 8 outputs. The system can switch transparent time slot whose size can range from 10 nsec to 1 sec. Each slot is reserved very quickly by an extended Resource reSerVation Protocol (RSVP) message that is now being standardized for the GMPLS control plane. According to calculations, the proposed system can handle more than 500 users with minimum receiving power of -18dBm, which is about an 8 fold improvement over Passive Optical Network (PON). We consider that the system well supports content distribution in the access network..
140. Hiroyuki Miyagi, Yusuke Okazaki, Ryota Usui, Yutaka Arakawa, Satoru Okamoto, Naoaki Yamanaka, Performance evaluation of grid computing with parallel routes transmission, IEICE Transactions on Communications, 10.1093/ietcom/e91-b.12.3882, E91-B, 12, 3882-3885, 2008.01, In a grid computing environment, the network characteristics such as bandwidth and latency affect the task performance. The demands for bandwidth of wide-area networks become large and it reaches more than 100 Gbps. In this article, we focus on parallel routes transmission, such as link aggregation, to realize large bandwidth network. The performance of grid computing with parallel routes transmission is evaluated on the emulated wide-area network..
141. Hiroyuki Miyagi, Masahiro Hayashitani, Daisuke Ishii, Yutaka Arakawa, Naoaki Yamanaka, A deadline-aware scheduling scheme for wavelength assignment in λ grid networks, 2007 IEEE International Conference on Communications, ICC'07 2007 IEEE International Conference on Communications, ICC'07, 10.1109/ICC.2007.400, 2383-2387, 2007.12, A deadline-aware scheduling scheme for the λ grid system is proposed to support a huge computer grid system based on an advanced photonic network technology. The assignment of wavelengths to jobs in order to efficiently carry various services is critical in λ grid networks. Such services have different requirements such as the job completion deadlines and wavelength assignment must consider the job deadlines. The conventional job scheduling approach assigns a lot of time-slots to a call within a short period in order to finish the job as quickly as possible. This raises the blocking probability of short deadline calls. Our proposal assigns wavelengths in A grid networks so as to meet QoS (Quality of Service) guarantees. The proposed scheme assigns time-slots to a call over time according to its deadline, which allows it to increase the system performance in handling short deadline calls, for example, lowering their blocking probability. Computer simulations show that the proposed scheme can reduce the blocking probability by a factor of 100 compared with the conventional scheme under the low load condition in which the ratio of long deadline calls is high. The proposed scheduling scheme can realize more efficient A grid networks..
142. M. Hayashitani, T. Kasahara, D. Ishii, Yutaka Arakawa, S. Okamoto, N. Yamanaka, N. Takezawa, K. Nashimoto, Design and implementation of GMPLS-based optical slot switching access-distribution network using PLZT ultra-high speed optical switch, OFC/NFOEC 2007 - Optical Fiber Communication and the National Fiber Optic Engineers Conference 2007 OFC/NFOEC 2007 - Optical Fiber Communication and the National Fiber Optic Engineers Conference 2007, 10.1109/OFC.2007.4348850, 2007.12, We design and implement a GMPLS-based optical slot switching access-distribution network using PLZT switches. Switching speed is better than 10 nsec and the network has a large scalability, 1000 users, compared to PON..
143. Teruo Kasahara, Masahiro Hayashitani, Yutaka Arakawa, Satoru Okamoto, Naoaki Yamanaka, Design and implementation of GMPLS-basd optical slot switching network with PLZT high-speed optical switch, 2007 IEEE Workshop on High Performance Switching and Routing, HPSR 2007 IEEE Workshop on High Performance Switching and Routing, HPSR, 10.1109/HPSR.2007.4281270, 48-53, 2007.12, In this paper, we propose a new optical network architecture, called Optical Slot Switching (OSS), suitable for large data transmission where we use PLZT optical switch controlled by GMPLS(Generalized Multi-Protocol Label Switching). PLZT ultra-high speed optical switch can improve the bandwidth efficiency by reducing the guard time between data compared with the conventional optical switch. In OSS network, user dynamically establishes the path and can transport a large size data efficiently by using reserved slots in a moment. Through the experimental results, we show that our proposed OSS is suitable for large data transmission..
144. Hiroyuki Ishikawa, Sho Shimizu, Yutaka Arakawa, Naoaki Yamanaka, Kosuke Shiba, New parallel shortest path searching algorithm based on dynamically reconfigurable processor DAPDNA-2, 2007 IEEE International Conference on Communications, ICC'07 2007 IEEE International Conference on Communications, ICC'07, 10.1109/ICC.2007.332, 1997-2002, 2007.12, This paper proposes a parallel shortest path-searching algorithm and implements it on a newly structured parallel reconfigurable processor, DAPDNA-2 (IPFlex Inc). Routing determines the shortest paths from the source to the ultimate destination through intermediate nodes. In Open Shortest Path First (OSPF), Dijkstra's shortest path algorithm, which is the conventional one, finds the shortest paths from the source on a program counter-based processor. The calculation time for Dijkstra's algorithm is O(N2) when the number of nodes is N. When the network scale is large, calculation time required by Dijkstra's algorithm increases rapidly. It's very difficult to compute Dijkstra's algorithm in parallel because of the need for previous calculation results, so Dijkstra's algorithm is unsuitable for parallel processors. Our proposed scheme finds the shortest paths using a simultaneous multi-path search method. In contrast with Dijkstra's algorithm, several nodes can be determined at one time. Moreover, we partition the network into different groups (network groups) and find the all-node pair's shortest path in each group using a pipeline operation. Networks can be abstracted, and the shortest paths in very large networks can be found easily. The proposed scheme can decrease calculation time from O(N2) to O(N) using a pipeline operation on DAPDNA-2. Our simulations show that the proposed algorithm uses 99.6% less calculation time than Dijkstra's algorithm. The proposed algorithm can be applied to the very large Internet network designs of the future..
145. Hiroyuki Miyagi, Masahiro Hayashitani, Daisuke Ishii, Yutaka Arakawa and Naoaki Yamanaka,, Advanced Wavelength Reservation Method based on Deadline-Aware Scheduling for Lambda Grid Networks, Journal of Lightwave Technology, Vol. 25, No. 10, pp. 2904-2910, 2007.10.
146. Hiroyuki Miyagi, Masahiro Hayashitani, Daisuke Ishii, Yutaka Arakawa, Naoki Yamanaka, Advanced wavelength reservation method based on deadline-aware scheduling for lambda grid networks, Journal of Lightwave Technology, 10.1109/JLT.2007.904416, 25, 10, 2904-2910, 2007.10, A deadline-aware-scheduling scheme for the lambda grid system is proposed to support a huge computer grid system based on an advanced photonic network technology. The assignment of wavelengths to jobs in order to efficiently carry various services is critical in lambda grid networks. Such services have different requirements such as the job-completion deadlines, and wavelength assignment must consider the job deadlines. The conventional job scheduling approach assigns a lot of time slots to a call within a short period in order to finish the job as quickly as possible. This raises the blocking probability of short deadline calls. Our proposal assigns wavelengths in the lambda grid networks to meet quality-of-services guarantees. The proposed scheme assigns time slots to a call over time according to its deadline, which allows it to increase the system performance in handling short deadline calls, for example, lowering their blocking probability. Computer simulations show that the proposed scheme can reduce the blocking probability by a factor of 100 compared with the conventional scheme under the low load condition in which the ratio of long deadline calls is high. The proposed scheduling scheme can realize more efficient lambda grid networks..
147. Yutaka Arakawa, Naoaki Yamanaka, Iwao Sasase, Optical burst switched ring network with upstream prioritized switching and distributed fairness control, Electronics and Communications in Japan, Part I: Communications (English translation of Denshi Tsushin Gakkai Ronbunshi), 10.1002/ecja.20338, 90, 8, 30-39, 2007.08, With a view to constructing a metropolitan network that can flexibly handle highly bursty traffic, an optical burst switched ring network with upstream prioritized switching and distributed fairness control is proposed. In optical burst switching, high burst drop rates at intermediate nodes constitute a problem. In the proposed system, burst signal dropping at the relay nodes is eliminated by means of upstream prioritized switching. At the same time, by using distributed fairness control, the problem of upstream prioritized switching-related unfairness, in which positional priority provides higher priority to more distant transmission nodes, is resolved. Further, by modifying the reservation of downstream nodes by using the trailer packet after disconnection of the transmission, unnecessary bandwidth is eliminated and the throughput is improved. By computer simulation, the throughput and the fairness with regard to the throughput are evaluated. It is shown that the proposed architecture exhibits excellent characteristics even in cases of hot-spot traffic, in which concentrated traffic occurs at a particular destination..
148. Yutaka Arakawa, Naoaki Yamanaka, QoS differentiation scheme with multiple burst transmission and virtual resource reservation for optical burst switching networks, Journal of Optical Networking, 10.1364/JON.6.001003, 6, 8, 1003-1013, 2007.08, We propose what we believe to be a new scheme to provide basic quality of service (QoS) in optical burst switching networks. Our proposal consists of multiple burst transmission (MBT) and virtual resource reservation (VRR). With MBT, consecutive bursts headed to the same destination are serially transmitted, and, at the transmission of high-priority bursts, the wavelength resource reserved by the head burst is kept reserving for the following bursts. We call it VRR. Computer simulations show that our proposal offers a larger differentiation of burst loss than the conventional offset-based QoS differentiation scheme. Also, it can improve the burst loss rate of both high-priority and low-priority bursts. Moreover, it can minimize the burst loss rate of high-priority bursts even when the high-priority traffic occupies a large percentage of the network traffic. The proposed scheme can be applied to the future multiservice optical network architecture..
149. Yutaka Arakawa and Naoaki Yamanaka,, QoS Differentiation Scheme with Multiple Burst Transmission and Virtual Resource Reservation for Optical Burst Switching Networks, Journal of Optical Networking, Vol. 6, Issue. 8, pp. 1003-1013, 2007.07.
150. M. Hayashitani, T. Kasahara, D. Ishii, Yutaka Arakawa, S. Okamoto, N. Yamanaka, N. Takezawa, K. Nashimoto, Design and implementation of GMPLS-based optical slot switching access-distribution network using PLZT ultra-high speed optical switch, Optical Fiber Communication Conference, OFC 2007 Optical Fiber Communication Conference, OFC 2007, 2007.01, We design and implement a GMPLS-based optical slot switching access-distribution network using PLZT switches. Switching speed is better than 10 nsec and the network has a large scalability, 1000 users, compared to PON..
151. Yutaka Arakawa, Naoaki Yamanaka, A new QoS differentiation scheme in optical burst switching with on-the-fly path setup mechanism, 2006 Optical Fiber Communication Conference, and the 2006 National Fiber Optic Engineers Conference Proceedings - Thirteenth International Symposium on Temporal Representation and Reasoning, TIME 2006, 2006.12, In order to meet the requirement of data grid or CD/DVD delivery which require the characteristic QoS e.g. multiple bursts transmission, we propose a new QoS differentiation scheme based on OBS/OCS integrated network architecture with on-the-fly path setup mechanism..
152. Sho Shimizu, Yutaka Arakawa, Naoaki Yamanaka, A wavelength assignment scheme for WDM networks with limited range wavelength converters, 2006 IEEE International Conference on Communications, ICC 2006 2006 IEEE International Conference on Communications, ICC 2006, 10.1109/ICC.2006.255202, 2787-2792, 2006.12, In this paper, we propose a new wavelength assignment scheme that improves the blocking probability of WDM networks that use limited-range wavelength converters. Limited-range wavelength converters are attractive for wavelength-routed networks given current technology since they offer good utilization of the wavelength resource and improved blocking probability. However, their conversion ranges are limited, the maximum difference between the input and output wavelengths is restricted. Thus, we must take into account the existence of these limitedrange wavelength converters. In our proposed scheme, each connection request is assigned a different wavelength according to its hop number. We tend to use different wavelengths for connection requests with different hop numbers. As a result, we can reduce the blocking probability by two decades compared to simply assigning the shortest available wavelengths. In addition, it allows the number of wavelength converters used in each node to be reduced with almost no degradation in blocking probability. Simulation results show that the proposed scheme can reduce the wavelength converters by about 20%..
153. Sho Shimizu, Yutaka Arakawa, Naoaki Yamanaka,, Wavelength assignment scheme for WDM networks with limited-range wavelength converters, Journal of Optical Networking, Vol. 5, No. 5, pp. 410-421, 2006.05.
154. Sho Shimizu, Yutaka Arakawa, Naoaki Yamanaka, Wavelength assignment scheme for WDM networks with limited-range wavelength converters, Journal of Optical Networking, 10.1364/JON.5.000410, 5, 5, 410-421, 2006.01, We propose a new wavelength assignment scheme that improves the blocking probability of WDM networks that use limited-range wavelength converters. Limited-range wavelength converters are attractive for wavelength-routed networks, given current technology, since they offer good utilization of the wavelength resource and improved blocking probability. However, their conversion ranges are limited; the maximum difference between the input and the output wavelengths is restricted. Thus we must take into account the existence of these limited-range wavelength converters. In our proposed scheme, each connection request is assigned a different wavelength according to its hop number. We tend to use different wavelengths for connection requests with different hop numbers. As a result, we can reduce the blocking probability by two decades compared with simply assigning the shortest available wavelengths. In addition, the scheme allows the number of wavelength converters used in each node to be reduced with almost no degradation in blocking probability. Simulation results show that the proposed scheme can reduce the wavelength converters by about 20% on the simple ring network and by 37.5% on the 14-node NSFNet network..
155. Chie Ishida, Yutaka Arakawa, Iwao Sasase, Keisuke Takemori, Forecast techniques for predicting increase or decrease of attacks using bayesian inference, 2005 IEEE Pacific RIM Conference on Communications, Computers, and Signal Processing, PACRIM 2005 IEEE Pacific RIM Conference on Communications, Computers, and Signal Processing, PACRIM - Proceedings, 10.1109/PACRIM.2005.1517323, 450-453, 2005.12, The analysis techniques of intrusion detection system (IDS) events are actively researched, since it is important to understand attack trends and devise countermeasures against incidents. To aim at a quick response in security operation, it is necessary to forecast a fluctuation of attacks. However, there is no approach for predicting the fluctuation of attacks, since the fluctuation of attacks seems to be random. In this paper, we propose forecast techniques for predicting increase or decrease of the attacks by using the Bayesian Inference for calculating the conditional probability based on past-observed event, counts. We consider two algorithms by focusing on an attack cycle and a fluctuation range of the event counts. We implement a forecasting system and evaluate it with real IDS events. As a result, our proposed technique can forecast increase or decrease of the event counts, and be effective to various types of attacks..
156. Takamasa Isohara, Yutaka Arakawa, Keisuke Takemori, Iwao Sasase, SKI
Security key infrastructure for a server audit certification, 6th Asia-Pacific Symposium on Information and Telecommunication Technologies, APSITT 2005 6th Asia-Pacific Symposium on Information and Telecommunication Technologies, APSITT 2005 - Proceedings, 350-355, 2005.12, An authentication technology such as Public Key Infrastructure (PKI) is used for a server authentication. However, it does not certificate a status of a server side security countermeasures, e.g., a configuration and operating condition of a Firewall (FW), a Virus Detection System (VDS) and an Intrusion Detection System (IDS). When a client machine communicates the server that is vulnerable to the attack, the server may affect the critical damage to the client machine. In this paper, we propose a Security Key Infrastructure (SKI) scheme that verifies the server side security countermeasures by linkage between an external and an internal audit. We consider requirements for designs of the SKI scheme, and implement communication modules between the server and the client machine. It is shown that the proposed SKI can achieve a quick response of the server and provide the certification of the security countermeasures to the client machine..
157. Yutaka Arakawa, Naoaki Yamanaka, Iwao Sasase, Performance of Optical Burst Switched WDM ring network with TTFR system, IFIP TC6/WG6.10 1st Optical Networks and Technologies Conference, OpNeTec 2004 Optical Networks and Technologies - IFIP TC6/WG6.10 1st Optical Networks and Technologies Conference, OpNeTec 2004, 95-102, 2005.01, In this paper, we propose an architecture of Optical Burst Switched WDM ring network. In our proposed OBS ring network, every node is equipped with one tunable transmitter and one fixed-tuned receiver (TTFR) oparating on a given wavelength that identifies the node. TTFR type ring network has an advantage that no receiver collisions occur and each node can detect channel collision by transmitter side. By computer simulations, we evaluate the performance of throughput, goodput, and queueing delay. As a result, we show the performance effectiveness of our proposed architecture and access protocol..