In this paper, we proposed a robust tetrahedron generation method based on advancing front method. This method inherits advantages from Delaunay method and advancing front method. Firstly, the minimum container box of mesh surface is calculated and points are inserted into the box. Secondly, for every surface triangle, a sphere is defined with a radius which equals to the average value of the edge length of the triangle and points in the sphere is divided into two groups according to whether they are already used for other triangles or not and the shape quality of the tetrahedron generated by them and the triangle. Then proper point is picked out to generate tetrahedrons layer by layer from surface to the inner. And a shoes model with both convex and concave surface is chosen for the experiment. The result proved the robust and correct of the method.

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The feasibility for cooling and mechanical strength around TSV (Through Silicon Via) structures in 3D SIP (System in Package) were discussed in this study with ADVENTURECIuster, large scale simulator on the basis of finite element method. Required cooling efficiency for the heat sink of the SIP was shown, and a liquid cooling system has to be considered. Thermal stresses in the chip were shown by elastic stress analysis. Stresses in TSV were like hydrostatic pressure and the magnitude of the equivalent stress was lower than yield stress of copper. However, it was noticed that the axial stress in TS V, that was 100 MPa, cannot be ignored.

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Ultraviolet protection by eyeglasses, e.g., sunglasses and welding goggles, is important because exposure to ultraviolet radiation causes disorder of oculus. In addition to that, the transmission of visible light is also important to obtain visibility and the color of human sensitivity. Sunglasses are also used for fashion eyewear. Eyeglasses with optical multilayer coatings is able to control ultraviolet radiation and visible radiation. The optimum structure of the multilayer coatings is designed to satisfy the appropriate ultraviolet protection and the user's sense of color that is influenced by spectral transmission in visible range. In this paper, optimum structure of the multilayer coatings is designed to satisfy the ultraviolet protection and the user's sense of color.

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[in Japanese]

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In this paper, we describe a method using compact support radial basis functions (CSRBF) for the emoticons generation control on mobile phones. The advantage of CSRBF is to compress function information efficiently as compared with other function representation techniques. In the generation method, we process a photo in the following procedure. Firstly, we load an image from the local file system in mobile phones. Secondly, we select the original points and destination points for the emoticon generation, such as mouth, eyes. Then, at last, emoticons will be generated using the function of CSRBFs. A sample photo is been used as the sample for experiment, the result demonstrates that this method is a practical one and using this method can obtain good results.

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[in Japanese]

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This paper deals with one-dimensional thermal, electrical and mechanical responses of a piezoceramic thin film subjected to impulsive loadings. The formulation of the problem is based on the generalized dynamic theory of thermoelasticity proposed by Green and Lindsay (the G-L theory), and/or Lord and Shulman (the G-L theory). In addition to the coupling between thermal, electrical and mechanical fields, the damping effect of resonance type is also considered. The problem is analyzed by the method of characteristics. The numerical calculations are carried out for PZT-4 thin films subjected to impulsive surface heating.

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Recently, roll forming attracts attention as a processing method of an axis and a gear used for a car. It is necessary to examine analysis of roll forming by using finite element method for improvement of processing accuracy. The objective of this study was to examine the effect of the work material properties on the work shape after forming. The work shape was much affected by the work hardening coefficient.

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The presence of nonlinear convection terms complicates the solving of the non-stationary Navier-Stokes equations, and this difficulty increases with the Reynolds number. In this work, the characteristic-curve method is employed to handle this term. The method is advantageous as it renders the matrix for linear equations symmetric, thus enabling the Conjugate Gradient (CG) method to be used together with the Schur complement system of the Domain Decomposition Method (DDM). By using a stabilization technique, the inf-sup condition need not be met for P1/P1 elements, which are swift and efficient to be implemented. The algorithm is implemented in parallel by the Hierarchical Domain Decomposition Method (HDDM), and it is feasible to solve large scale models over 100 million Degrees Of Freedom (DOF).

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Hydrogen embrittlement is a well identified cause of material degradation and is the origin of major failure in industry. The deleterious effect of hydrogen uptake in metals and alloys is especially observed on mechanical properties. For most of the metal-hydrogen systems, fracture strength and fracture toughness are decreased and fatigue crack propagation is increased. Many attempts have already been made to investigate the metal-hydrogen interactions at macro-scale but the microstructure is generally not introduced into the analyses. The aim of this work is to propose a coupled mechanical-diffusion analysis taking into account explicitly the microstructure and using the finite element method. The stress-strain fields in artificial polycrystalline aggregates are obtained in the crystalline plasticity framework. A one-way coupled crystalline plasticity-transient hydrogen diffusion analysis is then employed to solve a boundary value problem of a large elasto-plastic deformation. The hydrogen distributions on all over the polycrystal including the hydrogen concentration within the grains and close to the grain boundaries are determined.

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Hydrogen can affect drastically the mechanical properties of stainless steels by the so called Hydrogen embrittlement. It is crucial to be able to describe the hydrogen content in the material especially at the microscopic scale. The diffusion process is depending on the fugacity of hydrogen on the surface, on the diffusivity and solubility in the bulk of the material. In the case of metastable austenitic stainless steels, strain-induced martensitic transformation modifies the diffusion process since the martensite and austenite have different solubilities and diffusivities. It is experimentally impossible to observe in situ and locally the diffusion process. Only the simulation is able to describe the diffusion at the microscopic scale in presence of two different phases. This work presents the finite element simulation of hydrogen diffusion in a model of microstructure corresponding at the microscopic scale to the real microstructure of a cold-rolled stainless steel. The spatial distribution of the different phases is obtained by the EBSD technique. From the phase map and some image analysis, a model is built and meshed for diffusion simulation. The drastic effect of the presence of martensitic domains on the hydrogen transport in the bulk of the material is clearly shown.

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