粒子法による高粘性流体解析手法を独自に開発し、開発した手法を用いてはちみつのコイリング現象（自由落下時に勝手に回転する現象）を解析し、
その動画が学会で一番高く評価された。

Authorship：Last author   Language：English   Publishing type：Research paper (scientific journal)  

DOI： https://doi.org/10.1016/j.tafmec.2024.104599

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DOI： 10.1016/j.engfracmech.2023.109637

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DOI： 10.1016/j.cma.2023.116203

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DOI： https://doi.org/10.1007/s40571-023-00666-y

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DOI： https://doi.org/10.1016/j.cma.2023.116203

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DOI： https://doi.org/10.1016/j.engfracmech.2023.109637

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粉体工学の分野において、ビーズミルの摩耗予測をすることは、機械のメンテナンス上重要なことであり、これを数値解析を通して簡易的に評価する方法を提案した。特に羽根の形状により、その摩耗特性は異なり、実験との比較検証をして十分に実用的であることを示した。

DOI： 10.4164/sptj.60.470

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DOI： 10.1088/2399-6528/ace416

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DOI： https://doi.org/10.1016/j.jcpx.2023.100125

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DOI： 10.1016/j.jcpx.2023.100125

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Language：Others   Publishing type：Research paper (scientific journal)   Publisher：Japan Society of Civil Engineers  

<p>SPH methods discretize a continuum with particles and update their position based on the Lagrangian description. Therefore, deformation of the domain can be represented by the movement of the particles. Besides, SPH methods generally use interpolation approximations with a fixed kernel depending on the distance from the target particle to the neighboring particles. Hence, its computational accuracy is guaranteed only when the particles are distributed regularly. Several methods to support its accuracy are proposed such as particle shifting methods, which re-arrange the particle configuration to a regular state, and the correction of differential models in response to particle disorder. In this context, we present a high accuracy second-order derivative model and demonstrate the performance improvement with several examples. In addition, we find that particle shifting methods provides higher-order approximation and simulation stability.</p>

DOI： 10.2208/jscejj.22-15019

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Language：Japanese   Publishing type：Research paper (scientific journal)   Publisher：Japan Society of Civil Engineers  

<p>With the rapid increase in torrential rainfall disasters and associated landslides, the demand for predictive numerical simulations has been growing. Due to computational limits, one needs to introduce approximations, however, the parameters to link detailed and approximated simulations (e.g. drag / bed friction coefficients) are determined empirically, and their applicability remains vague. In this context, this paper presents the application of a deep learning model, PINN (Physics-Informed Neural Network) to inverse analysis. This work assumes a scenario where one has an access to limited data (which is the case for real-site observation), and proposes utilizing data’s spatial features extracted from POD (Proper Orthogonal Decomposition) instead of conventional random number-based method. We found that proposed method supports PINN for faster training convergence and efficient parameter identification.</p>

DOI： 10.2208/jscejj.22-15011

CiNii Research

Language：Japanese   Publishing type：Research paper (scientific journal)   Publisher：Japan Society of Civil Engineers  

<p>In recent years, a number of bridges have been washed out due to torrential rains. When analyzing scour around piers, one of the causes of damage to bridges, using particle methods such as the SPH(Smoothed Particle Hydrodynamics) methods, the non-uniform distribution of particles and tensile instability caused by negative pressure occur. We especially focus on the pressure gradient model, which has been conventionally and frequently used for stable analysis, and discuss pressure gradient calculations suitable for negative pressure regions. Moreover we introduce a modified gradient model that satisfies first-order consistency as well as PS (Particle Shifting) scheme to maintain the particle distribution regularity. The modified SPH method reproduces von Karman vortex, and its validity is quantitatively examined by comparing the twin vortex size, drag coefficient, lift coefficient and Strouhal number with experimental data.</p>

DOI： 10.2208/jscejj.22-15023

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DOI： 10.1186/s40323-022-00239-3

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DOI： https://doi.org/10.1186/s40323-022-00239-3

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Language：English   Publishing type：Research paper (scientific journal)   Publisher：ELSEVIER SCI LTD  

The present work shows a novel phase-change concept for simulating landslides using the smoothed particles hydrodynamics (SPH) method. The idea is to initiate the simulation of a slope stability problem with a Solid Mechanics-based SPH, modeling the soil as an elastoplastic material at finite strain. Next, if a particle exceeds a certain level of plastic strain, such particle changes its phase to a fluid state with non-Newtonian rheology, which is then solved with a Fluid Dynamics-based SPH method. We use the total Lagrangian SPH (TLSPH) method to solve the Solid Mechanics phase to avoid problems related to particle distribution (such as the tensile instability), while the implicit incompressible SPH (IISPH) to solve the Fluid Dynamics part to avoid the restriction on time increment in relation to high values of viscosity. The coupling between the two phases is treated as a conventional fluid-solid interaction (FSI) problem. We verified the proposed TLSPH method with the triaxial compression problem and demonstrated the robustness of the proposed phase-change TLSPH-IISPH coupled method in the simulation of the Aso landslide. Specifically, it may be the first time to simulate the Aso landslide from its initiation to its propagation in a single numerical simulation.

DOI： 10.1016/j.compgeo.2022.104815

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DOI： 10.4164/sptj.60.470

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DOI： https://doi.org/10.1016/j.compgeo.2021.104570

Language：English   Publishing type：Research paper (scientific journal)   Publisher：ELSEVIER SCI LTD  

This paper is dedicated to the introduction of a strong coupled soil-water interaction formulation based on an incompressible smoothed particle hydrodynamics (ISPH) framework. The method is based on the u-w-p Biot's formulation and adapted to a semi-implicit projection method for incompressibility condition of pore water and soil grains. The SPH Lagrangian particles move according to the soil velocity, while water variables are embedded into such soil particles. This allows to solve the pressure Poisson equation in a strong coupling way, in addition to enable to update the Darcy's drag force implicitly. A simple boundary treatment on natural boundary conditions for soil particle is proposed to take into account both non-penetration and friction effects. The proposed method was verified and validated through a series of numerical tests resulting in good agreements with both theoretical and experimental results. Finally, we show the applicability of the proposed method in the famous Selborne experiment, a full-scale slope failure problem.

DOI： 10.1016/j.compgeo.2021.104570

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Language：Japanese   Publishing type：Research paper (scientific journal)  

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DOI： https://doi.org/10.1016/j.cma.2021.113832

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DOI： 10.1016/j.cma.2021.113832

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DOI： 10.1007/s40571-020-00347-0

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© 2021 The Author(s) In this paper, a new particle-based fluid–rigid-body interaction simulator for violent free-surface flow problems is developed. The incompressible Smoothed Particle Hydrodynamics (ISPH) method has been proven to produce a smooth and accurate pressure distribution of free-surface fluid flow with breaking and fragmentation. Computed hydrodynamic forces can be applied onto rigid bodies, which may simultaneously experience contact or impact with the surrounding wall boundaries or another rigid body. Modeled by using the discrete element method (DEM), the contact force between rigid bodies is traditionally calculated employing the penalty approach, where a spring-based repulsive force is approximated at the vicinity of contact points depending on the deepest penetration depth. However, for high-speed collision problems involving a system of many rigid bodies, the values of approximated repulsive forces may be highly overestimated, and thus, a much smaller time step and an excessive damping parameter are often required to stabilize the approximated forces. This problem is highly inefficient for the computational resources of the fluid–rigid body interaction simulation since the computational cost at each time step is mostly dominated by the incompressible fluid simulation. The capability to increase the time increment following the critical time step of the fluid solver is, therefore, strongly demanded to increase the simulation efficiency. The current paper incorporates the usage of the energy-tracking impulse (ETI) method as an alternative approach to handle contact accurately. To achieve better energy conservation and enhance stability, Stronge's hypothesis is considered instead of the generally assumed Newton's contact law. The current work also covers three experimental validation tests, which were conducted to assure the quality and robustness of the coupled ISPH–DEM implementation.

DOI： 10.1016/j.cma.2021.113681

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DOI： 10.1007/s40571-020-00326-5

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DOI： https://doi.org/10.1007/s40571-020-00326-5

Language：Japanese   Publishing type：Research paper (scientific journal)  

Language：Japanese  

<p>Many bridges and infrastrucutures were damaged by the seismic waves in the 2016 Kumamoto Earthquakes, and in this research, we focused on the Aso-bridge which collapsed immediately after the main shock. A huge landslide happened after the earthquakes and Aso-bridge, which was constructed in the same location of the landslide, totally collapsed. There are a couple of reports that four main factors might have contributed to this collapse; (1) seismic wave, (2) ground deformation, (3) landslide material load increase on the bridge, (4) basement ground collapse. In this paper, a numerical analysis of the Aso-Bridge collapse was conducted using the ASI-Gauss code, which is one of the finite element method utilizing beam elements. Then, we have discussed the main factor of the Aso-bridge collapse.</p>

DOI： 10.11532/structcivil.66A.59

Language：Japanese   Publishing type：Research paper (scientific journal)  

Language：Japanese  

<p>昨今，高度成長期から発達してきた下水道管路の不具合に伴う地盤陥没被害が多発している．本研究では，未だ解析例の少ない地盤陥没現象の 3 次元数値解析を実施した．解析手法として，大変形かつ不連続な運動も追随できる粒子法をベースとした流体－地盤混相流解析手法の開発を行い，粉体工学の分野で研究されている液体架橋力を導入することで，含水に伴う見かけの粘着力を考慮し，不飽和地盤に適応できるように改良を施した．本手法を用いた陥没現象の再現解析により，定性的な陥没現象の再現することに成功し，不飽和地盤における見かけの粘着力と粒子形状の評価の必要性について考察を行った．</p>

DOI： 10.2208/jscejam.75.2_I_203

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DOI： 10.1007/s40571-019-00231-6

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DOI： 10.1007/s40571-019-00231-6

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Improvements in highly viscous fluid simulation using a fully implicit SPH method
This study describes the application of two main improvements in highly viscous fluid simulations using the smoothed particle hydrodynamics (SPH) method: an implicit time integration scheme to overcome the problem of impractically small time step restriction and the introduction of air ghost particles to fix problems regarding the free surface treatment.

DOI： 10.1007/s40571-019-00231-6

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DOI： https://doi.org/10.11421/jsces.2018.20182010

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DOI： https://doi.org/10.11421/jsces.2018.20182010

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DOI： 10.1051/matecconf/20164703019

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Publisher：Theoretical and Applied Fracture Mechanics  

Recent decades have witnessed a growing interest in simulating interfacial debonding in laminated structures using cohesive zone (CZ)-based algorithms. In the present work, we develop a nodal-based Lagrange multiplier/cohesive zone (LM/CZ) approach to achieve the end with a special focus on interfacial multi-cracks in dissimilar laminated structures. The main advantages of the developed approach are four-folded: (1) being flexible for the mesh discretization of dissimilar laminated structures and compatible with various element types; (2) being computationally more efficient for dissimilar laminated structures; (3) addressing the so-called artificial compliance issue arising in intrinsic CZ modeling; (4) providing smooth transitions from uncracked to cracking states, and from cracking to contact states. In the presented approach, nodal pairs are constructed with the aid of a searching algorithm capable of dealing with matching and non-matching meshes in a unified manner. For each nodal pair, the displacement continuity is accurately enforced using LMs that are calculated in a predictor–corrector manner with a limited number of iterations. The constraints for nodal pairs are switched from LMs to cohesive forces after a defined criterion is satisfied. The non-penetration condition between interfaces is fulfilled using penalty-based contact forces in the cracking and pure contact states, leading to a smooth transition from cracking to contact states. The accuracy and effectiveness of the presented approach are validated using three benchmark tests. Finally, the capacity of the approach to describe interfacial multi-crack behaviors of dissimilar laminated structures has been exploited and demonstrated.

DOI： 10.1016/j.tafmec.2024.104599

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Language：Japanese   Publisher：JAPAN SOCIETY FOR COMPUTATIONAL ENGINEERING AND SCIENCE  

<p>While the particle method is suitable for representation of large and discontinuous deformations, it is prone to accuracy degradation and numerical instability due to issues with particle distribution. To solve this problem, SPH(2) has been proposed, which can perform highly accurate calculations even when there are disturbances in the particle distribution. But is still limited in overcoming numerical instability. From previous studies, it is found that more stable and accurate calculations can be achieved by using SPH(2) in combination with the particle shifting technique. However, the existing particle shifting technique tends to expand the volume in the long term smulations. Therefore, we propose a new particle rearrangement method that can simultaneously improve particle homogeneous distribution and volume conservation. For this purpose, it is also important to use the proposed method in combination with other stabilization techniques, and our policy is to sort out the roles of various stabilization techniques and eliminate unnecessary terms. In addition, the numerical stability and accuracy improvement of the proposed method are demonstrated by Rotating square patch fluid simulations and Dam break simulations.</p>

DOI： 10.11421/jsces.2024.20241007

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Language：Japanese   Publisher：JAPAN SOCIETY FOR COMPUTATIONAL ENGINEERING AND SCIENCE  

<p>The discontinuous Galerkin (DG) method is effective and promising tool for the hyperbolic equations with discontinuities. In recent years, the DG method has been applied and shown to be effective in the analysis of shallow water equations (SWEs), which are widely used for river flooding, storm surge, tsunami, and other natural disaster simulations. In this study, the DG method is applied to the governing equations for riverbed variation, which are coupling of the SWEs and equilibrium sediment transport equation, and wetting-drying treatment and numerical flux are discussed for our purpose. The proposed method has been verified with numerical analysis such as erodible dam-break flow and sandbar migration simulation. The numerical results have shown that the proposed method is effective for riverbed variation analysis.</p>

DOI： 10.11421/jsces.2024.20241006

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CiNii Research

Language：Japanese   Publishing type：Research paper (scientific journal)   Publisher：Japan Society of Civil Engineers  

<p>Particle methods such as the SPH and MPS methods have problems in that the approximation accuracy decreases due to disorder in particle arrangements and it is difficult to treat accurately curved bottom surfaces such as seabed surface. Regarding the first problem, we proposed the SPH(2), which satisfy the second order convergence in space and maintain its accuracy against for particle disorders. In this study, the second problem, the treatments of the curved bottom surfaces, has been improved using a coordinate transformation with the SPH(2)'s second derivative model Although the theory for the coordinate transformation was established in the MPS method, its accuracy did not give the desired accuracy because of the numerical errors of the second derivative models. Therefore, the numerical errors in these coordinate transformations were overcome by applying the second derivative model of SPH(2) to the coordinate transformation formulas. The superiority and validity of the proposed coordinate transformation using SPH(2) are demonstrated through validation examples such as hydrostatic pressure problems and dam breakage problems.</p>

DOI： 10.2208/jscejj.23-15017

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Language：Japanese   Publisher：Japan Society of Civil Engineers  

<p>For simulating the fluidized ground during landslides, a new ISPH using the fully implicit time integration has been developed to decrease total simulation costs for highly viscous fluid simulation in non-Newtonian fluids. With the help of the proposed fully implicit ISPH, <i>μ</i>(<i>I</i>) rheology model, which is one of the reliable non-Newtonian fluids for dense granular materials, can be implemented with lower numerical costs than the semi-implicit ISPH keeping the same accuracy. The fully implicit ISPH method was implemented on a GPU computer to speed up their heavy computations and achieve stable and fast analysis by combining hardware speed-up and software improvement. Finally, comparing numerical and experimental results for sand flow supports the usefulness of the <i>μ</i>(<i>I</i>) rheology model and fully implicit ISPH method for granular flow.</p>

DOI： 10.2208/jscejj.23-15018

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DOI： 10.1038/s41598-023-44098-3

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Publisher：Numerical Heat Transfer; Part A: Applications  

The ISPH method is adopted to simulate the diffusion of solid particles through a nanofluid flow during the dual rotation of two circular cylinders inside a cavity. Half of the solid particles are carrying (Formula presented.) and the others carry (Formula presented.). The novelty of this work is in simulating the dual rotation of circular cylinders with the dispersion of solid particles below the influences of Soret-Dufour numbers. The major outcomes revealed that the interactions between solid particles and nanofluid flow are enhanced according to an increase in Soret/Dufour numbers. Increasing the Hartmann number declines the interaction process between solid particles and nanofluid flow. The radius of a circular cylinder is working well in changing the transport of heat/mass within a cavity due to the variations in the total number of solid particles. The values of Nusselt and Sherwood numbers are influenced by physical factors.

DOI： 10.1080/10407782.2022.2156413

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Publisher：Journal of Advanced Research in Fluid Mechanics and Thermal Sciences  

Incompressible Smoothed Particle Hydrodynamic (ISPH), one of the particle methods, is frequently employed to address a variety of challenging physical issues, such as those involving free surface flow. For measuring the precise and reliable pressure close to the boundary, the study of boundary treatment has lately been an active research field in the mesh-free or particle approach. If the solid barrier's appropriate pressure boundary condition is not met, fluid particles may penetrate it. This study proposes a straightforward boundary treatment that can satisfy the non-homogenous Neumann boundary condition on the solid boundary and the Dirichlet condition on the water surface. The main idea behind our suggested approach is that by solving a modified pressure Poisson equation, these boundary conditions are automatically satisfied. This technique can be improved such that it can be applied to any shape having a concave-convex boundary in addition to basic solid boundaries. The suggested method was tested using the hydrostatic case, followed by a numerical analysis validated using a 3D dam break flow with an opening gate and a Stanford rabbit demonstration. The outcome of the numerical modelling simulation was then contrasted with the findings of the theoretical and experimental studies. The obtained findings support the suggested technique by providing a good tendency and similarity output that enhances the boundary treatment on solid boundaries

DOI： 10.37934/arfmts.103.1.211222

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Language：Japanese   Publisher：The Society of Powder Technology, Japan  

<p>While the Discrete Element Method (DEM) is expected to evaluate wet grinding performance of bead mills, the conventional DEM requires high computational cost because it has the limitation of the time step size for stable computation. In addition, the simulation of wet grinding process requires additional cost to consider the interaction between beads and fluids by using such as CFD-DEM coupling techniques. This study proposes an analysis system for evaluating wet grinding performance of bead mills with less computational cost. Our proposed system adopts the Impulse-Based DEM (IB-DEM) which can use large time step size, the wall model by using the Sign Distance Function (SDF) which flexibly represents complicated shape walls, and the simple modeling of fluid force which can reduce computational cost. We verify our proposed system by comparing the numerical results with experimental results of bead mills with different shapes of rotors.</p>

DOI： 10.4164/sptj.59.488

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CiNii Research

Language：English   Publishing type：Research paper (scientific journal)   Publisher：TAYLOR & FRANCIS LTD  

Numerous tsunami numerical models have been proposed, but their prediction accuracies have not been directly compared. For quantifying the modeling uncertainties, the authors statistically analyzed the prediction results submitted by participants in the tsunami blind contest held at the 17th World Conference on Earthquake Engineering. The reproducibility of offshore water level generated due to the tsunami with soliton fission significantly decreased when the nonlinear shallow water equation models (NSWE) was used compared to three-dimensional (3D) models. The inundation depth was reproduced well in 3D models. However, the reproducibility of wave forces acting on the structure and velocities over land was lower in 3D models than that in NSWE models. For cases where the impulsive tsunami wave pressure generated could not be calculated based on the hydrostatic assumption, the prediction accuracy of the NSWE models was higher than that of the 3D models. The prediction accuracies of both models were not improved at small grid-cell sizes. The NSWE model cannot simulate the short-wave component and vertical pressure distribution. Therefore, further developments in 3D models and smoothed particle hydrodynamics methods (SPH) are needed. The presented results contribute to the future development of tsunami numerical simulation tools.

DOI： 10.1080/21664250.2022.2072611

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Language：Japanese   Publisher：Japan Society of Civil Engineers  

<p>There has been a growing demand to strengthen existing disaster prevention education tobe prepared for the huge tsunami expected to occur in the near future. Virtual reality, which allows people to virtually experience natural disasters, has a strong potential in fostering disaster awareness among citizens. However, it requires enormous human and time resources to map the texture of structures to urban area-imitating virtual space. On the other hand, pix2pixHD proposed by Wang et al. can generate high-resolution synthetic images by learning from reference images, label data, and object boundary data. In this study, we applied pix2pixHD and transfer learning, which diverts networks trained on other similar domains, to verify texture mapping of urban areas in Japan from a limited set of image data.</p>

DOI： 10.11532/jsceiii.3.j2_551

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DOI： 10.1108/HFF-02-2020-0094

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DOI： 10.32604/cmc.2020.09227

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DOI： 10.1108/HFF-02-2020-0094

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<p>2011 年の東北地方太平洋沖地震後に発生した津波による防波堤の崩壊原因としては，防波堤前後の水位差による水平力，浸透流によるマウンドの支持力低下に伴うパイピング破壊，越流水によるマウンドの洗掘が主因となり，これらが連成することで崩壊に至ったものと考えられている．著者らはこうした複雑な水と土の相互作用に起因する土構造物の破壊を予測するため，SPH 法と個別要素法(DEM)による水‐土連成解析手法を開発してきた．本研究では，特に礫のみを対象とした洗掘現象に対して，解析ツールによる解析精度の妥当性確認を行いながら，乱流状態となる礫表層部分の抗力モデルの改良の必要性について議論し，その修正モデルを提案し，実験との比較検証を通してその有用性を確認した．</p>

DOI： 10.2208/jscejam.75.2_I_249

Language：Japanese  

<p>非圧縮性 Navier–Stokes 方程式に対する粒子法の一つである安定化 ISPH 法は，通常の非圧縮性 SPH 法 (ISPH 法) に粒子密度に関する安定化項を圧力 Poisson 方程式に付加した手法である．この安定化項により，粒子の偏在化を防ぐことができ，計算安定，体積保存，精度向上などが数値計算によって確かめられている．この安定化 ISPH 法に対して，我々は先行研究で安定化項が非圧縮性条件と局所密度一定の条件の誤差を重み付きで近似的に最小化するという解釈ができることを理論的に示した．しかしながら，その誤差の重みを表す安定化係数については，いくらかの数値実験によって最適な範囲や傾向が見積もられているものの，それらを理解するための理論は存在しなかった．そこで，本論文では，経験的に知られている安定化係数の範囲や他のパラメータとの関係性を，誤差評価に基づいて安定化係数を最適化する．さらに，その最適化された安定化係数の性質を示すことで経験則で知られていたことを理論的に解釈する．</p>

DOI： 10.2208/jscejam.75.2_I_187

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DOI： 10.1108/HFF-03-2019-0270

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DOI： 10.1108/HFF-03-2019-0270

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DOI： 10.1142/S0219876218430090

Language：English   Publishing type：Research paper (other academic)  

Bingham flow model by fully implicit SPH and its application to reinforce underground caves
© 2019 Taylor & Francis Group, London. The present work shows the application of the Smoothed Particle Hydrodynamics (SPH) on non-Newtonian fluids for simulating the injection of a cementitious material into underground caves to reinforce the soil. In special, it presents two main improvements over the already established SPH formulation: an implicit time integration scheme to overcome the problem of impracticable small time step restriction in highly viscous fluid simulation, and the introduction of air ghost particles (AGP) to fix problems on the free-surface treatment. This project utilizes the Incompressible SPH (ISPH) as a basis for the implementation of such improvements, which guarantees a stable and accurate pressure distribution. We validate the proposed implicit time integration scheme with pipe flow simulations and the free-surface treatment with a simple hydrostatic problem. Also, dam break numerical simulations using the proposed method resulted in very good agreement with experimental data. At last, we demonstrate the potential of this method with the highly viscous vertical jet flow over a horizontal plate validation test, which shows a complex viscous coiling behavior.

DOI： 10.1201/9780429327933-48

Language：Japanese  

DOI： 10.2208/jscejam.74.I_159

Language：Others   Publishing type：Research paper (scientific journal)  

DOI： 10.1007/s42241-018-0133-3

Language：English   Publishing type：Research paper (scientific journal)  

DOI： 10.1002/ecj.12050

Language：Japanese   Publishing type：Research paper (scientific journal)  

Language：Japanese  

DOI： 10.2208/jscejseee.74.I_1052

Language：Others  

DOI： 10.11421/jsces.2018.20182010

Language：Others  

DOI： 10.11421/jsces.2018.20182001

Language：Others  

DOI： 10.1541/ieejeiss.137.1422

Language：English   Publishing type：Research paper (scientific journal)  

DOI： 10.11345/nctam.64.143

Language：Japanese  

Language：English   Publishing type：Research paper (other academic)  

Language：English   Publishing type：Research paper (other academic)  

Language：English   Publishing type：Research paper (scientific journal)  

DOI： 10.1142/S1793431116400200

Language：English   Publishing type：Research paper (scientific journal)  

DOI： 10.1142/S1793431116400194

Language：English   Publishing type：Research paper (other academic)  

DOI： 10.1051/matecconf/20164702019

Language：Others   Publishing type：Research paper (scientific journal)  

DOI： 10.1108/HFF-10-2014-0305

Language：Others   Publishing type：Research paper (scientific journal)  

DOI： 10.1007/s11242-015-0568-8

Language：Others   Publishing type：Research paper (scientific journal)  

DOI： 10.1007/s11242-015-0568-8

Language：Others   Publishing type：Research paper (scientific journal)  

DOI： 10.1007/s11242-015-0568-8

Language：Others   Publishing type：Research paper (scientific journal)  

DOI： 10.1080/10407790.2014.955772

Language：Japanese   Publishing type：Research paper (scientific journal)  

Language：Japanese  

On March 11, 2011, the huge tsunami caused by the great east Japan earthquake devastated the Pacific coast of north-eastern Japan. Many infrastructures including bridges were collapsed by the tsunami. New generation of tsunami disaster prevention and mitigation method should be reconsidered toward the next millennium Tsunami. In this study, a new boundary treatment using a virtual marker and the fixed boundary particle is developed to control the slip and no-slip boundary condition for the velocity field and to satisfy the pressure Neumann condition at the same time. Finally, the accuracy and efficiencies of our proposed method are validated by comparison between a numerical solution and experimental results.

DOI： 10.11532/structcivil.60A.293

Language：English   Publishing type：Research paper (scientific journal)  

DOI： 10.1615/InterJFluidMechRes.v41.i6.10

Language：English   Publishing type：Research paper (scientific journal)  

DOI： 10.1108/09615531311301263

Language：Others  

Coupling simulator between chemical diffusion and crack propagation by a Voxel FEM incorporated with the Damage Mechanics
Alkali Silica Reaction (ASR), chloride damage of reinforced steel and other aging degradations in concrete structures are strongly dependent on both of chemical phenomena and mechanical behavior including fracture. In this study, a coupling simulator has been developed in order to investigate the degradation mechanism of these concrete aging damages. In the coupling simulator, non-stationary diffusion analysis for Alkali ion is solved firstly, and then the expansion force act on the aggregate is evaluated by referring consistency of the alkali ion. In the second step, nonlinear damage analysis is conducted. The nonlinear damage analysis evaluates cracking region with the damage parameter. The following diffusion analysis changes diffusion coefficient in the cracking region by referring the damage parameter. The above procedures are coupled at each time step. © 2013 by the Japan Society for Computational Engineering and Science.

Language：Japanese  

Slip and no-slip boundary treatment for particle simulation model with incompatible step-shaped boundaries by using a virtual maker
Particle method such as Smoothed Particle Hydrodynamics (SPH) and Moving Particle Semi-implicit method (MPS) can handle quite complicated physical problems involving dynamic changes of free surface and crack propagation, and it is wildly expanding its applications not only in the fluid dynamics but also in the solid mechanics. Beside of these advantages, particle methods are not so easy to treat boundary conditions, like pressure Neumann condition and slip or no-slip condition in fluid dynamics. This is one of the typical difficulties in mesh-less type method. In addition, particle simulation model may include an incompatible step-shaped boundary line, which is made by using a simple pre-processing of particle model. Although the simple and robust pre-processing is one of the advantage of particle simulation, the step-shaped boundary may generate un-realistic numerical solution across the real boundary line especially in the fluid dynamics. Recently, pressure Neumann condition in SPH is re-focused with fixed ghost boundary method using virtual makers. In this paper, the fixed ghost boundary method is modified to treat the incompatible step-shaped boundary particles by referring the real physical boundary line. The accuracy and efficiencies of proposed method are validated by comparison between a numerical solution and experimental results. © 2013 by the Japan Society for Computational Engineering and Science.

DOI： 10.11421/jsces.2013.20130011

Language：Others  

Coupling simulator between chemical diffusion and crack propagation by a Voxel FEM incorporated with the Damage Mechanics
Alkali Silica Reaction (ASR), chloride damage of reinforced steel and other aging degradations in concrete structures are strongly dependent on both of chemical phenomena and mechanical behavior including fracture. In this study, a coupling simulator has been developed in order to investigate the degradation mechanism of these concrete aging damages. In the coupling simulator, non-stationary diffusion analysis for Alkali ion is solved firstly, and then the expansion force act on the aggregate is evaluated by referring consistency of the alkali ion. In the second step, nonlinear damage analysis is conducted. The nonlinear damage analysis evaluates cracking region with the damage parameter. The following diffusion analysis changes diffusion coefficient in the cracking region by referring the damage parameter. The above procedures are coupled at each time step. © 2013 by the Japan Society for Computational Engineering and Science.

Language：Others  

Slip and no-slip boundary treatment for particle simulation model with incompatible step-shaped boundaries by using a virtual maker
Particle method such as Smoothed Particle Hydrodynamics (SPH) and Moving Particle Semi-implicit method (MPS) can handle quite complicated physical problems involving dynamic changes of free surface and crack propagation, and it is wildly expanding its applications not only in the fluid dynamics but also in the solid mechanics. Beside of these advantages, particle methods are not so easy to treat boundary conditions, like pressure Neumann condition and slip or no-slip condition in fluid dynamics. This is one of the typical difficulties in mesh-less type method. In addition, particle simulation model may include an incompatible step-shaped boundary line, which is made by using a simple pre-processing of particle model. Although the simple and robust pre-processing is one of the advantage of particle simulation, the step-shaped boundary may generate un-realistic numerical solution across the real boundary line especially in the fluid dynamics. Recently, pressure Neumann condition in SPH is re-focused with fixed ghost boundary method using virtual makers. In this paper, the fixed ghost boundary method is modified to treat the incompatible step-shaped boundary particles by referring the real physical boundary line. The accuracy and efficiencies of proposed method are validated by comparison between a numerical solution and experimental results. © 2013 by the Japan Society for Computational Engineering and Science.

Language：English   Publishing type：Research paper (scientific journal)  

Language：English   Publishing type：Research paper (international conference proceedings)  

Language：English   Publishing type：Research paper (international conference proceedings)  

Language：Japanese   Publishing type：Research paper (scientific journal)  

Language：English   Publishing type：Research paper (international conference proceedings)  

Language：English   Publishing type：Research paper (international conference proceedings)  

Language：English   Publishing type：Research paper (international conference proceedings)  

Publishing type：Research paper (international conference proceedings)  

Language：English   Publishing type：Research paper (international conference proceedings)  

Language：English   Publishing type：Research paper (international conference proceedings)  

Language：Others  

Constitutive modeling for texture reinforced rubber by using an anisotropic visco-hyperelastic model
Fabric reinforced rubber shows an anisotropy and viscosity in wide strain range. In this paper, an anisotropic visco-elastic model based on Mooney-Rivlin model is developed for fabric reinforced rubber. Anisotropy is introduced, in this constitutive model, by using a structure tensor that shows direction of reinforced fiber. A new strain energy density function for anisotropic elasticity is proposed to improve accuracy associated with shear behaviors. After developing an elastic model, an anisotropic viscosity is modeled by a kind of Maxwell viscosity model at large strains. In addition to the development of constitutive model, a simple fracture prediction method, which refers to the finite element solution incorpolated with our proposed constitutive model, is proposed. Finally, our proposed constitutive model and fracture prediction method are validated with comparisons of uni-axial tension tests with fabric reinforced rubber.

DOI： 10.2208/jsceja.66.194

Language：Japanese  

Constitutive modeling for texture reinforced rubber by using an anisotropic visco-hyperelastic model
Fabric reinforced rubber shows an anisotropy and viscosity in wide strain range. In this paper, an anisotropic visco-elastic model based on Mooney-Rivlin model is developed for fabric reinforced rubber. Anisotropy is introduced, in this constitutive model, by using a structure tensor that shows direction of reinforced fiber. A new strain energy density function for anisotropic elasticity is proposed to improve accuracy associated with shear behaviors. After developing an elastic model, an anisotropic viscosity is modeled by a kind of Maxwell viscosity model at large strains. In addition to the development of constitutive model, a simple fracture prediction method, which refers to the finite element solution incorpolated with our proposed constitutive model, is proposed. Finally, our proposed constitutive model and fracture prediction method are validated with comparisons of uni-axial tension tests with fabric reinforced rubber.

DOI： 10.2208/jsceja.66.194

Language：English   Publishing type：Research paper (scientific journal)  

Language：English   Publishing type：Research paper (international conference proceedings)  

Language：Japanese   Publishing type：Research paper (scientific journal)  

Publishing type：Research paper (scientific journal)  

Language：English   Publishing type：Research paper (scientific journal)  

Reduction of Finite Element Mesh and Model Order for Fast Dynamic Analysis of Global/Local Problem
MEMS structures and machines fabricated by photolithography and/or etching have often repeated unit microstructure. We need to design not only the global parameters but also microscopic and local parameters. In pursuit of this, a dynamic analysis of global/local problem is essential, and especially fast computational method and convenient modeling technique are both required for the MEMS design. Hence, this paper presents the application of model order reduction (MOR) for fast dynamic analysis combined with the finite element mesh superposition (FEMS) technique for practical and convenient modeling of the above-mentioned microstructures. Through two examples, the accuracy is carefully investigated for both global and local responses associated with the base vectors in MOR algorithm. The first example is analyzed by a kind of homogenization technique and MOR. The number of DOFs was finally reduced by a factor of approximately 1/6 (47,362/296,268). In addition, MOR enabled us to reduce the coefficient matrix size to only 300. The second example is analyzed by both FEMS and MOR, and it was found that MOR is also applicable to an unusual matrices generated by FEMS.

DOI： 10.1299/jmmp.3.572

Language：English   Publishing type：Research paper (scientific journal)  

Reduction of Finite Element Mesh and Model Order for Fast Dynamic Analysis of Global/Local Problem

Language：Japanese   Publishing type：Research paper (scientific journal)  

Language：English  

Language：Japanese  

Language：English   Publishing type：Research paper (scientific journal)  

DOI： 10.1088/0965-0393/15/6/002

Language：English   Publishing type：Research paper (scientific journal)  

DOI： 10.1088/0965-0393/15/6/002

Language：English   Publishing type：Research paper (scientific journal)  

DOI： 10.1243/03093247JSA233

Language：English   Publishing type：Research paper (scientific journal)  

DOI： 10.1243/03093247JSA233

Language：English   Publishing type：Research paper (scientific journal)  

DOI： 10.1243/03093247JSA233

Language：Japanese   Publishing type：Research paper (scientific journal)  

Language：Japanese  

This paper presents an image-based multi-scale analysis in order to evaluate macroscopic properties of heterogeneous porous piezoelectric materials by finite element calculations. The multi-scale analysis is based on the mathematical homogenization theory. Material heterogeneity is represented as a micro structure FE model that is automatically generated from the cross-sectioned images by high resolution X-ray CT. The high resolution X-ray measurement for porous PZT is compared with the digital image of SEM. Radius of pore is quantified from their images to compare these images. Nodal blocking preconditioned iterative solver is developed for piezoelectric FEM with high degree of freedom. In the numerical examples, material properties of porous PZT materials with different porosity are evaluated by the image-based multi-scale analysis to show the applicability and efficiency. Image-based multi-scale analysis with one million elements can be conducted by conventional PC with help of the proposed iterative solver.

DOI： 10.2472/jsms.55.1111

Language：Japanese  

This paper presents an image-based multi-scale analysis in order to evaluate macroscopic properties of heterogeneous porous piezoelectric materials by finite element calculations. The multi-scale analysis is based on the mathematical homogenization theory. Material heterogeneity is represented as a micro structure FE model that is automatically generated from the cross-sectioned images by high resolution X-ray CT. The high resolution X-ray measurement for porous PZT is compared with the digital image of SEM. Radius of pore is quantified from their images to compare these images. Nodal blocking preconditioned iterative solver is developed for piezoelectric FEM with high degree of freedom. In the numerical examples, material properties of porous PZT materials with different porosity are evaluated by the image-based multi-scale analysis to show the applicability and efficiency. Image-based multi-scale analysis with one million elements can be conducted by conventional PC with help of the proposed iterative solver.

DOI： 10.2472/jsms.55.1111

Language：Japanese   Publishing type：Research paper (scientific journal)  

Language：Japanese  

This paper presents the multi-scale stress analysis of trabecular bone by the homogenization method bridging nano-micro-macro scales. Three-dimensional microstructure of trabeculae is obtained by the X-ray CT and the image-based modeling technique. Biological apatite (BAp) crystallite orientation is considered in the microstructure model by means of the anisotropic mechanical properties. The c-axis of BAp is set up as the maximum principal stress direction under the long term macroscopic stress condition. These properties are automatically assigned to each voxel element. To determine appropriately the microstructure model, the trabeculae morphology is analyzed and quantified as the trabecular density distribution. The proposed method is applied to pig's femur. It was revealed by the morphology analysis and homogenized macroscopic properties that the trabecular bone has plate-like characteristics. The predicted anisotropic level of the macroscopic properties was quantitatively coincident with the measured value by the X-ray diffraction analysis.

DOI： 10.2472/jsms.55.874

Language：Japanese  

This paper presents the multi-scale stress analysis of trabecular bone by the homogenization method bridging nano-micro-macro scales. Three-dimensional microstructure of trabeculae is obtained by the X-ray CT and the image-based modeling technique. Biological apatite (BAp) crystallite orientation is considered in the microstructure model by means of the anisotropic mechanical properties. The c-axis of BAp is set up as the maximum principal stress direction under the long term macroscopic stress condition. These properties are automatically assigned to each voxel element. To determine appropriately the microstructure model, the trabeculae morphology is analyzed and quantified as the trabecular density distribution. The proposed method is applied to pig's femur. It was revealed by the morphology analysis and homogenized macroscopic properties that the trabecular bone has plate-like characteristics. The predicted anisotropic level of the macroscopic properties was quantitatively coincident with the measured value by the X-ray diffraction analysis.

DOI： 10.2472/jsms.55.874

Language：Japanese   Publishing type：Research paper (bulletin of university, research institution)  

Language：Japanese  

DOI： 10.2472/jsms.55.237

Language：Japanese  

DOI： 10.2472/jsms.55.237

Language：Others  

Finite cover method for physically and geometrically nonlinear problems

Language：English   Publishing type：Research paper (scientific journal)  

Language：English   Publishing type：Research paper (international conference proceedings)  

Language：Japanese  

従来のボクセル解析における材料界面での人工的な応力振動を回避するために積分平均化理論を導入する非局所型ボクセル有限要素法を提案し, 任意方向に進展する不連続面の取り扱いが簡便であるエレメント除去技術を導入して不連続面進展解析手法へと拡張する. 非局所変数の算定方法, 破壊基準, 不連続面進展の解析アルゴリズムなどについて述べた後, 数値解析例を示して手法の妥当性・適用性を検証する. 特に, 材料界面における応力振動の問題だけでなく, 要素除去に起因する要素寸法依存性に対しても積分平均化理論を適用して算出する非局所ひずみ・応力が有効に機能することを示す. また, コンクリート材料のような非均質脆性材料を想定して, 微視的な非均質性に起因した不連続面進展挙動やその強度特性を表す2軸破壊包絡線の再現を試みる.

DOI： 10.2208/jscej.2004.759_233

Language：English   Publishing type：Research paper (scientific journal)  

DOI： 10.1002/nme.820

Language：English   Publishing type：Research paper (scientific journal)  

DOI： 10.1002/nme.820

Language：Japanese   Publishing type：Research paper (scientific journal)  

Language：English  

Meso-scopic numerical analysis of concrete structures by a modified lattice model
Realistic simulation of the mechanical behavior of concrete and reinforced concrete structures is performed by using a lattice type numerical model. Five different types of lattice members with simple constitutive models are introduced for mortar, coarse aggregate, steel, aggregate-mortar interface and steel-concrete interface. The meso-scopic morphology of concrete, which can be realized by the image-based geometry modeling technique, is taken into account. By the incorporation of the accurate meso-scopic morphology into the lattice type numerical modeling, the cracking behavior induced by the meso-scopic heterogeneities has been successfully captured.

DOI： 10.2208/jsceseee.20.43s

Language：English  

DOI： 10.2208/jscej.2003.731_19

Language：English  

Meso-scopic numerical analysis of concrete structures by a modified lattice model
Realistic simulation of the mechanical behavior of concrete and reinforced concrete structures is performed by using a lattice type numerical model. Five different types of lattice members with simple constitutive models are introduced for mortar, coarse aggregate, steel, aggregate-mortar interface and steel-concrete interface. The meso-scopic morphology of concrete, which can be realized by the image-based geometry modeling technique, is taken into account. By the incorporation of the accurate meso-scopic morphology into the lattice type numerical modeling, the cracking behavior induced by the meso-scopic heterogeneities has been successfully captured.

DOI： 10.2208/jsceseee.20.43s

Language：Japanese   Publishing type：Research paper (scientific journal)  

Language：Japanese   Publishing type：Research paper (scientific journal)  

Language：Japanese   Publishing type：Research paper (scientific journal)  

Language：English  

Language：Japanese   Publishing type：Research paper (scientific journal)  

Publishing type：Research paper (scientific journal)  

Language：Japanese   Book type：Scholarly book

Language：Japanese   Book type：Scholarly book

Language：Japanese   Book type：General book, introductory book for general audience

Language：Japanese   Book type：Scholarly book

Language：Japanese  

CiNii Books

Responsible for pages：総ページ数：v, 225p   Language：Japanese  

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Event date： 2018.4

Language：English   Presentation type：Oral presentation (invited, special)  

Country：Korea, Republic of  

Event date： 2018.4

Language：English   Presentation type：Oral presentation (general)  

Country：Korea, Republic of  

Event date： 2018.3

Language：Japanese   Presentation type：Oral presentation (general)  

Venue：宮崎大学   Country：Japan  

Event date： 2018.3

Language：Japanese   Presentation type：Oral presentation (general)  

Venue：宮崎大学   Country：Japan  

Event date： 2018.3

Language：Japanese   Presentation type：Oral presentation (general)  

Venue：宮崎大学   Country：Japan  

Event date： 2018.3

Language：Japanese   Presentation type：Oral presentation (general)  

Venue：宮崎   Country：Japan  

Event date： 2018.3

Language：Japanese   Presentation type：Oral presentation (general)  

Venue：宮崎   Country：Japan  

Event date： 2017.10

Language：English   Presentation type：Oral presentation (general)  

Country：China  

Event date： 2017.10

Language：English   Presentation type：Oral presentation (invited, special)  

Venue：Chengdu   Country：China  

Event date： 2017.10

Language：English   Presentation type：Oral presentation (invited, special)  

Venue：Chengdu   Country：China  

Event date： 2017.10

Language：English   Presentation type：Oral presentation (general)  

Country：China  

Event date： 2017.10

Language：English   Presentation type：Oral presentation (general)  

Country：China  

Event date： 2017.10

Language：English   Presentation type：Oral presentation (general)  

Country：China  

Event date： 2017.9

Language：English   Presentation type：Oral presentation (general)  

Country：Germany  

Event date： 2017.9

Language：English   Presentation type：Oral presentation (general)  

Country：Germany  

Event date： 2017.9

Language：English   Presentation type：Oral presentation (general)  

Venue：Hannover   Country：Germany  

Event date： 2017.9

Language：Japanese   Presentation type：Oral presentation (general)  

Venue：関西大学   Country：Japan  

Event date： 2017.9

Language：Japanese   Presentation type：Oral presentation (general)  

Venue：関西大学   Country：Japan  

Event date： 2017.9

Language：Japanese   Presentation type：Oral presentation (general)  

Country：Japan  

Event date： 2017.9

Language：Japanese   Presentation type：Oral presentation (general)  

Venue：九州大学   Country：Japan  

Event date： 2017.9

Language：Japanese   Presentation type：Oral presentation (general)  

Venue：九州大学   Country：Japan  

Event date： 2016.9

Language：Japanese   Presentation type：Oral presentation (general)  

Venue：北九州   Country：Japan  

Event date： 2016.9

Language：Japanese   Presentation type：Oral presentation (general)  

Venue：久留米   Country：Japan  

Event date： 2013.11

Language：Japanese   Presentation type：Oral presentation (general)  

Venue：佐賀   Country：Japan  

Event date： 2013.9

Language：English   Presentation type：Oral presentation (general)  

Country：Germany  

Event date： 2013.7

Language：English   Presentation type：Oral presentation (general)  

Country：United States  

Event date： 2012.11

Language：Others   Presentation type：Oral presentation (general)  

Country：Korea, Republic of  

Event date： 2012.5

Language：Others   Presentation type：Oral presentation (general)  

Venue：京都   Country：Japan  

Event date： 2011.4

Language：Others   Presentation type：Oral presentation (general)  

Country：Korea, Republic of  

Event date： 2010.9

Language：Others   Presentation type：Oral presentation (general)  

Venue：札幌   Country：Japan  

Event date： 2009.9

Language：Others  

Venue：福岡大学，福岡   Country：Japan  

Event date： 2024.9

Language：Japanese   Presentation type：Oral presentation (general)  

Venue：仙台   Country：Japan  

Event date： 2024.9

Language：Japanese   Presentation type：Oral presentation (general)  

Venue：仙台   Country：Japan  

Event date： 2024.9

Language：Japanese   Presentation type：Oral presentation (general)  

Venue：仙台   Country：Japan  

Event date： 2024.9

Language：Japanese   Presentation type：Oral presentation (general)  

Venue：仙台   Country：Japan  

Event date： 2024.9

Language：Japanese   Presentation type：Oral presentation (general)  

Venue：仙台   Country：Japan  

Event date： 2024.9

Language：Japanese   Presentation type：Oral presentation (general)  

Venue：仙台   Country：Japan  

Event date： 2024.9

Language：Japanese   Presentation type：Oral presentation (general)  

Venue：仙台   Country：Japan  

Event date： 2023.9

Language：Japanese   Presentation type：Oral presentation (general)  

Venue：広島   Country：Japan  

Event date： 2023.9

Language：Japanese   Presentation type：Oral presentation (general)  

Venue：広島   Country：Japan  

Event date： 2023.9

Language：Japanese   Presentation type：Oral presentation (general)  

Venue：広島   Country：Japan  

Event date： 2023.9

Language：Japanese   Presentation type：Oral presentation (general)  

Venue：広島   Country：Japan  

Event date： 2023.9

Language：Japanese   Presentation type：Oral presentation (general)  

Venue：広島   Country：Japan  

Event date： 2023.9

Language：Japanese   Presentation type：Oral presentation (general)  

Venue：広島   Country：Japan  

Event date： 2023.9

Language：Japanese  

Venue：広島   Country：Japan  

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Event date： 2023.9

Language：Japanese  

Venue：広島   Country：Japan  

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Event date： 2023.9

Language：Japanese  

Venue：広島   Country：Japan  

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Event date： 2023.9

Language：Japanese  

Venue：広島   Country：Japan  

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Event date： 2023.9

Language：Japanese  

Venue：広島   Country：Japan  

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Event date： 2023.9

Language：Japanese  

Venue：広島   Country：Japan  

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Event date： 2023.5 - 2023.6

Language：English   Presentation type：Oral presentation (general)  

Country：Japan  

Event date： 2023.5 - 2023.6

Language：Japanese   Presentation type：Oral presentation (general)  

Venue：筑波   Country：Japan  

Event date： 2023.5 - 2023.6

Language：Japanese   Presentation type：Oral presentation (general)  

Venue：筑波   Country：Japan  

Event date： 2023.5 - 2023.6

Language：Japanese   Presentation type：Oral presentation (general)  

Venue：筑波   Country：Japan  

Event date： 2023.5 - 2023.6

Language：Japanese   Presentation type：Oral presentation (general)  

Venue：筑波   Country：Japan  

Event date： 2023.5 - 2023.6

Language：Japanese   Presentation type：Oral presentation (general)  

Venue：筑波   Country：Japan  

Event date： 2023.5 - 2023.6

Language：English   Presentation type：Oral presentation (general)  

Country：Japan  

Event date： 2023.5 - 2023.6

Language：English   Presentation type：Oral presentation (general)  

Venue：筑波   Country：Japan  

Event date： 2023.5 - 2023.6

Language：Japanese   Presentation type：Oral presentation (general)  

Venue：筑波   Country：Japan  

Event date： 2023.5 - 2023.6

Language：English  

Venue：筑波   Country：Japan  

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Event date： 2023.5 - 2023.6

Language：English  

Venue：筑波   Country：Japan  

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Event date： 2023.5 - 2023.6

Language：Japanese  

Venue：筑波   Country：Japan  

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Event date： 2023.5 - 2023.6

Language：Japanese  

Venue：筑波   Country：Japan  

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Event date： 2023.5 - 2023.6

Language：Japanese  

Venue：筑波   Country：Japan  

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Event date： 2023.5 - 2023.6

Language：Japanese  

Venue：筑波   Country：Japan  

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Event date： 2023.5 - 2023.6

Language：Japanese  

Venue：筑波   Country：Japan  

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Event date： 2023.5 - 2023.6

Language：Japanese  

Venue：筑波   Country：Japan  

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Event date： 2023.5 - 2023.6

Language：English  

Venue：筑波   Country：Japan  

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Event date： 2023.5

Language：Japanese   Presentation type：Oral presentation (general)  

Venue：東京   Country：Japan  

Event date： 2023.5

Language：Japanese   Presentation type：Oral presentation (general)  

Venue：東京   Country：Japan  

Event date： 2023.5

Language：Japanese   Presentation type：Oral presentation (general)  

Venue：東京   Country：Japan  

Event date： 2023.5

Language：Japanese   Presentation type：Oral presentation (general)  

Venue：東京   Country：Japan  

Event date： 2023.5

Language：Japanese   Presentation type：Oral presentation (general)  

Venue：東京   Country：Japan  

Event date： 2023.5

Language：Japanese   Presentation type：Oral presentation (general)  

Venue：東京   Country：Japan  

Event date： 2023.5

Language：Japanese  

Venue：東京   Country：Japan  

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Event date： 2023.5

Language：Japanese  

Venue：東京   Country：Japan  

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Event date： 2023.5

Language：Japanese  

Venue：東京   Country：Japan  

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Event date： 2023.5

Language：Japanese  

Venue：東京   Country：Japan  

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Event date： 2023.5

Language：Japanese  

Venue：東京   Country：Japan  

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Event date： 2023.5

Language：Japanese  

Venue：東京   Country：Japan  

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Event date： 2023.3

Language：Japanese   Presentation type：Oral presentation (general)  

Venue：熊本大学   Country：Japan  

Event date： 2023.3

Language：Japanese   Presentation type：Oral presentation (general)  

Venue：熊本大学   Country：Japan  

Event date： 2023.3

Language：Japanese   Presentation type：Oral presentation (general)  

Venue：熊本大学   Country：Japan  

Event date： 2023.3

Language：Japanese  

Venue：熊本大学   Country：Japan  

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Event date： 2023.3

Language：Japanese  

Venue：熊本大学   Country：Japan  

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Event date： 2023.3

Language：Japanese  

Venue：熊本大学   Country：Japan  

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Event date： 2022.11

Language：Japanese   Presentation type：Oral presentation (general)  

Venue：オンライン   Country：Japan  

Event date： 2022.11

Language：Japanese  

Venue：オンライン   Country：Japan  

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Event date： 2022.9

Language：Japanese   Presentation type：Oral presentation (general)  

Venue：京都   Country：Japan  

Event date： 2022.9

Language：Japanese   Presentation type：Oral presentation (general)  

Venue：京都   Country：Japan  

Event date： 2022.9

Language：Japanese   Presentation type：Oral presentation (general)  

Venue：京都   Country：Japan  

Event date： 2022.9

Language：Japanese   Presentation type：Oral presentation (general)  

Venue：京都   Country：Japan  

Event date： 2022.9

Language：Japanese   Presentation type：Oral presentation (general)  

Venue：京都   Country：Japan  

Event date： 2022.9

Language：Japanese   Presentation type：Oral presentation (general)  

Venue：京都   Country：Japan  

Event date： 2022.9

Language：Japanese  

Venue：京都   Country：Japan  

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Event date： 2022.9

Language：Japanese  

Venue：京都   Country：Japan  

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Event date： 2022.9

Language：Japanese  

Venue：京都   Country：Japan  

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Event date： 2022.9

Language：Japanese  

Venue：京都   Country：Japan  

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Event date： 2022.9

Language：Japanese  

Venue：京都   Country：Japan  

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Event date： 2022.9

Language：Japanese  

Venue：京都   Country：Japan  

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Event date： 2022.6

Language：Japanese   Presentation type：Oral presentation (general)  

Country：Japan  

Event date： 2022.6

Language：English   Presentation type：Oral presentation (general)  

Country：Japan  

Event date： 2022.6

Language：English   Presentation type：Oral presentation (general)  

Country：Japan  

Event date： 2022.6

Language：Japanese   Presentation type：Oral presentation (general)  

Country：Japan