In this study, we propose the new algorithm for particle swarm optimization (PSO) of Artificial life (AL). PSO has been developed by the other researchers for AL like alternative algorithm such as a new method of evolutional computation for the optimal solutions. Our method is PSO algorithm combined with the gradient computation in multi-dimensional space. The AL has the sensing in the solution space, and we can get higher computation performance through the searching by AL particles . We show some basic numerical experiments of the optimal searching in the optimization problem, and this algorithm has the effectiveness and applicability.

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Wind data estimated by LES and observational data for urban wind are compared in order to validate the LES (large eddy simulation) model for strong wind around a super high-rise building in an actual urban area. The meteorological model (MM5) is utilized to introduce the absolute values for wind velocity on some specific date. We first investigate fundamental features of local flow characteristics for strong winds during cyclogenesis based on both of observational data on the rooftop of the high-rise building and at several surrounding points on the ground. Next, we numerically predict the mean wind speed and maximum instantaneous wind speed, and validate the LES method by comparison with observational data. We thus confirm the applicability of the present LES model coupled with MM5 for wind over an urban area represented by actual shapes.

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Our particular interest is a numerical treatment of noisy data for ill-posed problems of partial differential equations. Our method consists of the multiple-precision arithmetic system exflib developed by Dr. Fujiwara of Kyoto University for numerical computation and the high order finite difference method developed by Iijima for approximation of differential equations. In this paper, this combined method is applied to numerical solution to the Cauchy problem of the Laplace equation. A rank reduction technique is considered for regularization to the problem with noisy data.

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Numerical treatment of a singular nonlinear partial differential equation (PDE) is made, which is proposed to describe the evolution of the risk preference in the optimal investment problem under the random risk process. The unknown quantity is related to the Arrow-Pratt coefficient of absolute risk aversion with respect to the optimal value function. We present an effective numerical scheme to handle a singular PDE of this kind. Numerical implementation shows that our method is excellent.

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The drying shrinkage behavior of a concrete is a quite important issue. A lot of researches have studied about the behavior, and have analogized its mechanism or suggested the numerical model to reproduce the behavior.
However, there is a rare model which considers the merits of the past studies to expect the behavior of concrete structures. Thus, in this study, the simple model which is constructed by taking the merits into account is proposed, and is implement it into a three dimensional finite element code.

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In the case that vibroacoustic response is predicted using steady-state analysis, these actually exists the mid-frequency range in which there are no mature numerical methods. This paper deals with the novel Wave Based Method(WBM), a deterministic approach for the analysis in the wide frequency range. The 2D WBM code for interior problems developed in our research is extended to the exterior problems, and verified using a simple exterior coupled vibroacoustic problem. Then we apply it to simple models of a rocket launch pad to solve the exterior acoustic propagation problem with a wide geometric and frequency range. In the problem, it can be stated that the extended WBM are computationally more efficient and has more applicability to the steady-state propagation analysis at the launch pad.

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This paper made clear the mechanism of actual top spin and its improvement by lubrication of used and notched strings at the intersections using 10,000 frames/sec high-speed video analysis. Contrary to the hypothetical conventional spin theory, as the main (longitudinal) strings stretch and slide side ways more and they spring back by lubrication of notched strings, the ball is given more spin when the ball is released from the strings. The notches at string intersections reduce the spin rate of the ball. More spin produce longer contact time between ball and strings, resulting in the reduction of shock vibrations of the wrist joint during impact according to the impact simulation based on the experimental identification of racket-arm system. Furthermore, it showed that the spin rate of a newly strung racket without notch is much larger than that of a racket with lubricated used strings. The lubricant materials are most effective to the notched used strings.

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