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the 28th Conference on Computational Engineering and Science 2023
	Reduction of the human damage caused by natural disasters due to the frequent occurrence of abnormal weather events in recent years has become an urgent issue. Although it is possible to quantitatively evaluates risk based on the magnitude of the fluid force exerted on the human body due to flooding, it is virtually impossible to measure the fluid force inside an real structure on-site. Therefore, this research proposes a method for predicting fluid force on the human body through simulation using the particle method based CFD software Particleworks. We modeled the inside of a subway station as a structure that is expected to be at high risk from flooding, and evaluated the fluid forces that the human body receives. Visualizing the situation of such disasters in a realistic manner is also thought to contribute to disaster prevention education. Therefore, we also introduce SIMUNIMA, a visualization tool developed for analysis engineers to create realistic visualization images from simulation results.
the 12th European LS-DYNA Conference 2019
	Discrete Element Method (DEM) is widely used as a simulation method to investigate the behavior of powder materials. There are some advantages for DEM, e.g., DEM model can be used intuitively, DEM shows relatively stable computation and so on. While, DEM model is a hypothetical model based on the spring-mass model and there isn't governing equation of global behavior of powder material. Hence, DEM model includes many numerical parameters that the users must determine beforehand. In this presentation, the parameter identification procedure regarding compression experiment of polymer pellets are shown. Moreover, performance of coarse graining models for powder mixing problem is presented.
NAFEMS European Conference on Multiphysics Simulation 2018
	When changing the shape of the fluid region, remeshing is required for conventional mesh-based CFD computation, and the mesh shape may affect the simulation result. On the other hand, particle method based CFD does not require a mesh, so there is no mesh dependency in the result due to the change in the mesh shape of the fluid region. So shape optimization can be performed efficiently and accurately using particle method. In this presentation, the optimization of the shape of parts controlling the flow in the filtration unit was performed using CFD software Particleworks (Prometech Software) based on the MPS particle method, and it was confirmed that improvement of filtration performance was achieved The real product based on the optimum shape obtained by the optimization was produced and improvement of filtration performance was confirmed experimentally.
JSOL LS-DYNA & JSTAMP Forum 2017
	The concept of origami engineering that utilizes flexibility and lightweight and high strength space filling structure is now widely applied to actual products. In this presentation, the examples of application of origami engineering including assembly truss core panel which efficiently produces an ideal shape of a triangular pyramidal truss core panel, a method of manufacturing a reversely twisted origami structure by high frequency induction heating, origami helmet, tsunami pod which is application of elliptical origami, furthermore, application to medical and daily necessities of complicated origami shape, thick plate origami structure, vibration isolator utilizing nonlinear spring characteristics of folding structure etc. are introduced.
the 11th European LS-DYNA Conference 2017
	For concrete structures used for nuclear facilities, highly accurate prediction of failure mode is required by simulation. The failed concrete scatters or accumulates, and the influence of concrete deposited against secondary impact and seismic load can not be ignored to predict structural responces. Solid element - particle conversion capability in LS-DYNA is considered to be useful as a technique to model such concrete failure and debris deposition. In this paper the result of examining the capability of converting solid element to SPH element or DEM element and its options are reported.
the 28th Computational Mechanics Conference 2015
	The importance of accurate prediction of failure modes at nuclear facilities has been seriously recognized after the Fukushima Daiichi nuclear accident in 2011 and requirement od experiments using pipes and important equipments in nuclear power plant are increaseing. However, accident reproduction test using real material is difficult from the viewpoint of cost and safety. As an alternative, use of lead alloy is proposed since the lead alloy shows a failure mode from ductility to brittleness by changing the content of antimony (Sb). Therefore, in this study, we used optimization software to identify parameters of modified Gurson model, which is a constitutive model of ductile material. (The presentation of this research was awarded the Japan Society of Mechanical Engineers' 28th Computational Mechanics Lecture Excellence Lecture Award.)
11th Optimization Symposium 2014
	The CEO Sunao Tokura made a presentation about an application example using particle based CFD software Particleworks titled as "Optimization of Mixing Process using Particle Method MPS" at the 11th optimization symposium (OPTIS 2014) (organized by the Japan Society of Mechanical Engineering) held on December 12 and 13 in Kanazawa, Japan. Material production using mixing are used in various industries including food, pharmaceuticals, chemical products and so on. As the boundary conditions are changed by the rotation of impellers in the mixing process, it is considered that particle based methods which do not need mesh generation are suitable for such kind of problems. Mixing status of multi materials can be traced by counting the ratio of the number of particles using particle method and this technique can be applied for the optimization of many parameters in manufacturing, e.g., geometry and the number of rotation of impellers, location and geometry of inlet.
International CAE Conference 2014
	The CEO Sunao Tokura made a presentation about the simulation technique for fuel tank sloshing problem using combination of Particleworks and LS-DYNA titled as "Application of Particle Method MPS-Based CFD Software Particleworks for Product Design" at "International CAE Conference" (organized by EnginSoft, Italy) held on October 27 and 28, 2014 in Verona. In this presentation behavior of the fuel is simulated using Particleworks, then plastic deformation of the fuel tank caused by the pressure load obtained by Particleworks simulation is computed with LS-DYNA. As EnginSoft, the organizer of the conference, is also a LS-DYNA distributor in Italy, many LS-DYNA users attended and had interest in the unique analysis technique with the combination of LS-DYNA and a particle based CFD software.
"Fundamentals and Application on Impact Engineering" has been published
	The book contains the papers presented at the technical seminar "Impact Engineering Forum" sponsored by the Society of Material Science, Japan during the period from 2004 to 2008. Fundamental issues in impact engineering including wave propergation theory, impact experiment methods, constitutive equations, damage parameter identification etc. and the application of practical engineering problems including (impact response of reinforced concrete, numerical simulation of impact problems etc. are covered in this book. The book is useful for both the beginners and expart engineers in impact engineering field. (1st edition on May 25, 2014)
1st International Conference on Computational Engineering and Science for Safety and Environmental Problems "COMPSAFE2014"
	Extreme climatic events in global scale, huge earthquake, tsunami and similar catastrophic disasters have happened very frequently in recent years. More sophisticated cities and facilities may cause more severe human and economical damage by natural disasters. Protection technologies against natural disasters and solution on environmental problems based on computational engineering are strongly required. In this situation, 1st International Conference on Computational Engineering and Science for Safety and Environmental Problems "COMPSAFE2014" sponsored by the Japan Association for Computational Mechanics (JACM) and the Japan Society for Computational Engineering and Science (JSCES) was held in Sendai and many papers concerning natural disaster simulation, protection technologies and so on were presented. The auther made a presentation about the tsunami simulation and the vehicle damage estimation technique using a particle method MPS and impact analysis software LS-DYNA titled "Simulation Technique to Estimate Damage of Auto Body Washed Away by Flooding" using a particle method MPS and impact analysis software LS-DYNA. (April 13-16, 2014)
"Handbook on Industrial and Applied Mathematics" has been published
	"Handbook on Industrial and Applied Mathematics" compiled by The Japan Society for Industrial and Applied Mathematics has been published from Asakura Publishing (in Japanese). Wide range of fields including mathematical theories as the foundation, numerical analysis methods for fluid mechanics, fracture mechanics, optimization etc. and application in industries are comprehended in the book. The author contributes an article "Origami Engineering Function in Structural Strengthening of Origami : Development of New Core Material - Forming Method of Core Material from Space Filling" with Prof. Hagiwara at Meiji University. Readers can review interesting many topics for computational methods and these application which are considered notably important at present. (1st edition on October 25, 2013)
"Geometrical Mathematics for Origami and Its Industrial Application" has been published
	Industrial and Applied Mathematics Series Vol.3 "Geometrical Mathematics for Origami and Its Industrial Application" has been published from Kyoritsu Shuppan. One of the traditional papercraft origami can produce light wweight 3D structure from 2D geometry. Multidisciplinary researches for mathematical investigation and industrial application of the characteristics of origami have been executed continuously. The book contains totally seven chapters from preliminary to application issues. The auther writes the chapter 7 about the forming procedure of the core material. This chapter describes the detail of the procedure and the important key points for the forming simulation. We recommend the book for the engineers who have much interist in origami and space filling techniques for industrial application. (1st edition on September 25, 2012)
12^th LS-DYNA International Conference Report
	The LS-DYNA International Conference where users, distributers and developers of LS-DYNA participate has been held every two years in USA. The conference was held also in this year at the hotel near Detroit on June 4 and 5. The conference were divided into following 10 sessions; ·Automotive ·Occupant Safety ·Metal Forming ·Constitutive Modeling ·Fluid Structure Interaction/ALE ·Electromagnetic ·Optimization ·Blast/Impact ·Simulation ·Computing Technology The author made a presentation titled "Simulation for Forming and Performance Evaluation of Structures Developed Based on the Concept of 'ORIGAMI Engineering'" (photo). Many engineers from automotive industries and so on could have much interest in the characteristics of light weight and high strength for the products from Origami engineering. (June 4 & 5, 2012)
Collaboration with LSTC
Dr. John O. Hallquist, the original developer of LS-DYNA, President of LSTC, and me at the front of the headquarters of LSTC	Livermore Software Technology Corporation (LSTC) is undoubtedly one of aggressive developer of numerical analysis software in the world. LSTC is the development company of general-purpose finite element software LS-DYNA®, one of de facto standard for impact simulation such as vehicle crash. LSTC also develop a pre and post processor LS-PREPOST® which improves efficiency to use LS-DYNA, LS-OPT® for design optimization and so on. Our company collaborates with the staffs of the development team including excellent engineers, mathematicians, and computer scientists from all over the world and propose up-to-date analysis technology for CAE engineers as simple as possible.