There are two types of modeling for the lipid bilayer bio-membrane. Red Blood Cell is often modeled as a hyperelastic membrane due to their stiff cytoskeleton structure. On the other hand, liposome only has lipid-bilayer structure and it is modeled as a two-dimensional incompressible fluid due to the fluidity of lipid molecules on the membrane. In this study, the behaviors of vesicles which have different types of membranes mentioned above are discussed under the presence of shear flow.

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[in Japanese]

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We previously developed a crack propagation model to calculate crack paths using accumulated damage in micro-solder joints in semiconductor structures. We have now developed a method based on this crack propagation model, which we have called an accumulated damage model, to predict fatigue-crack propagation properties of solders. Generally, there is a correlation between crack propagation rates, da/dN, of solders and J-integral ranges, ΔJ. The correlation can be represented in an equation as a simple power relationship, given by da/dN=B[ΔJ]^q. We derive this simple power equation from our crack propagation model and Hutchinson-Rice-Rosengren singularity theory. The equation enabled us to estimate fatigue-crack propagation properties from cyclic stress-strain curves and fatigue strength properties. We used the method to predict fatigue-crack propagation properties for center-cracked plate specimens made of Sn-40Pb. The predictions were consistent with actual fatigue-crack propagation properties determined by experiment for center-cracked plate specimens made of Sn-40Pb, indicating that our method can be used to effectively predict solder fatigue-crack propagation properties.

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We propose a method to estimate image displacement by using RBF interpolation. This method can estimate image displacement such as parallel translation, rotation, and scale change at subpixel level. The evaluation function to be minimized is defined by the integral of square error between the interpolated images. Since RBF is expressed as the sum of Gaussian functions, we can compute the integral analytically and efficiently. We also present a method to reduce the computation time by efficiently selecting the region of summation.

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A simplified identification method using a thermoelastic boundary element method is proposed to estimate residual stress distribution due to weld. The proposed method can simply estimate residual stress distribution by few measurement data, which are measured by nondestructive (or destructive) method This paper examine the effects of the location of measurement point and measurement errors. The validity of the proposed method is demonstrated by numerical simulation by thermoelastic boundary element. The applicability and the effectiveness of the proposed method was confirmed by using measuring data with random measurement errors at two kinds of location of the measurement points..

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Free-Lagrange method has been combined with the free-mesh FEM and applied to the numerical simulation of viscous free surface flows. The nodes distributed over the fluid region are regarded as fluid particles and moved in a Lagrangian manner every time step. In this paper, we report a new numerical technique for calculating the interaction between the fluid and rigid walls. The proposed method has been applied to the broken-dam problem in a bounded region in which flowing liquid strikes a rigid vertical wall and run up along it. Encouraging numerical results have been obtained.

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We have developed MPS-AS (Moving Particle Semi-implicit for All Speed) method which is applicable to compressible and incompressible flows so far. In this study the variable effective radius is introduced to the MPS-AS method, in oder to handle large density changes.

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We tried the saving of memories of Enriched Free Mesh Method by applying Node by Node CG Method. However, the computing time has increased. An increase in the computing time in Memory Saving Direct Method is smaller than Node by Node CG Method. In this paper, we propose the saving of memories for Free Mesh Method by Memory Saving Direct Method.

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