It is important to create adequate mesh according to the mesh rules in order to assure the quality of simulation results since simulation results may vary depending on the input FEM mesh. However, it is time consuming to create adequate FEM mesh according to the mesh rules. This paper describes how we automatically generate precise mesh following detailed mesh rules by recognizing various specific features from the shape of input 3D CAD models and its future development. To recognize specific features for the mesh rules, we used characteristics of each face of the input 3D CAD models. Which characteristics we check varies on the features. In addition to simple features, we also developed feature recognition algorithm to recognize composite surface features. We recognize them by combination of faces and their cross sectional shape as well as characteristics of each face. We also discuss the probable future development of the feature recognition.

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In this paper, we utilized a simulation approach based on the dynamic explicit finite element method to evaluate the flowability of strand cut pellets in hopper. We clarified that the shape of fluorine resin strand cut pellets had a large influence on its flowability, and found an optimal pellet shape that can improve the flowability of the fluorine resin strand cut pellets.

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[in Japanese]

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[in Japanese]

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本研究では，新たな破壊理論として注目されている Peridynamics に基づいた数値解析システムとして，オープンソースで公開されている実装の１つである Peridigm（ペリダイム）を用いて，建設系構造物を対象とした破壊解析の応用事例を検証する．具体的には，建設現場での落下物に対する保安施設である朝顔養生の安全性評価を実現するために，薄肉鉄板に対する高度衝突における貫通に関する定量的評価を行う．本研究では高速衝突を考慮するために，歪み速度に対応した動的降伏強度を定義する事で，既往の衝突実験結果をまとめて作られた評価式（BRL 式）との比較検討を行った．様々な衝突速度に対応した動的降伏強度の評価式の値を用いることに加え，動的な破談伸びを設定することで評価式と対応した解析結果を得た.

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In this study, we present estimation analysis of flow behavior in shallow water region based on the ensemble Kalman filter FEM. The shallow water equation including the advection term is introduced as the governing equation, and the SUPG method is applied to discretize the governing equation in space. By the combination of the ensemble Kalman filter theory and the FEM, the estimation of the state value distribution considering the time history data of observation value is carried out. As the numerical model, the open channel model is employed.

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In this report, a semi-analytical approach for three dimensional contact problem of two non-conformed, deformable bodies in contact under normal loading is presented. The contact surfaces could be rough or smooth. For plastic deformation, the perfect elasto-plasticity is assumed. Rough surfaces of different roughness profiles can be independently defined on each body surface. The numerical solution is based upon the analytical solution given by Boussinesq-Cerruti integral equations for an elastic half space [1]. Due to the geometry restriction, the bodies in contact are assumed as flat or nearly flat where the radii of curvature is very large as compared to the contact area size. The integral equations applied at each contact body are discretized on a rectangular grid defined at each contact surface and are evaluated by using multilevel and multi-summation technique (MLMS) [2]. In addition to the discretized integral equations, the contact condition and force balance equations in normal direction are imposed. Iterated conjugate gradient method (CGM) [2] is implement to find the displacement and tractions that satisfy the contact conditions. The surface displacement and tractions in normal direction, the real contact area, plastic contact area are obtained under the given conditions.

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An automatic triangular mesh generation method considering the stress singularity near interface edge of bonded structures are proposed, and computational accuracy is evaluated by least square approximation. In addition, examination of inverse analysis for the order of singularity is also carried out. The finite element equation using the Akin singular element is employed in the inverse analysis of the order of singularity.

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In this study, we present the inverse analysis for identification of the hammering signal and the cavity position in non-destructive hammering test. The performance function is defined by square sum of residual between the obtained and the computed sound pressure. Here, the problem is to find the input sound pressure so as to minimize the performance function. The formulation for this problem is carried out by the adjoint variable method, and the numerical simulation of the sound pressure propagation is carried out based on the wave equation and the finite element method. In addition, the identification of the cavity position is also carried out based on the adjoint variable and the finite element methods.

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A Normal Crack in a Functionally Graded Thermal Barrier Coating Bonded to a Homogeneous Elastic Substrate under Transient Thermal Loading

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[in Japanese]

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Grammatical Evolution (GE), which is one of Evolutionary Computations (EC), is designed to find function or program satisfying the design objective. The candidate solutions are defined as the binary bit-strings. The genotype (bit-string) is translated into the phenotype such as function or program according to the translation rule which is defined in Backus Naur Form (BNF). The aim of this study is to apply GE to the design of LEGO Mindstorms EV3 control program. The designed program applied to the robot in real world after adjusting control parameters for bridging the gap between simulator and real world. As a result, the behavior in real world was roughly equivalent to in simulator.

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This paper introduces a new model formulation for the source term of the conservation equation in three-dimensional interface phenomena, which gives a diffusive solution of the level-set equation coupled with a re-initialization procedure. A gas-liquid interface model including the phase change and surface tension mechanism is derived as normal extension and curvature flow of interface by the new extensional level-set equation.

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[in Japanese]

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The aim of this study is to design the cultivation environment scenario in the rice plant cultivation. The use of the neural network determines the prediction model which predicts the yield and the quality of the rice from the environmental scenario. The objective function, which is defined from the yield and the quality, is maximized by changing the scenario of the daily average temperature. The result shows that the temperature before the heading date in Nagoya is too high for the rice Oryza sativa ’Koshihikari’.

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[in Japanese]

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[in Japanese]

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[in Japanese]

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[in Japanese]

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