Tubes based on Origami structure are considered to be advantageous to pedestrian and/or low speed Vehicle collision problems, and we examine its crashworthiness by finite element method simulation. As a result, we find out that Origami structures canot be folded completely in some cases. And if the fold is incompletely, the crashworthiness becomes worse. So here we examine in which case Origami structure can be folded completely.

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An investigation is made to analyze aCTual conneCTion strength between eleCTronic device and printed wired board (PWB) via solder paste. It is obviously important to know how many and how big void spots are generated in the solder and how severe the void affeCTs on the conneCTion strength. In this paper, to reproduce digitally the void spots is tried and to estimate the affeCTion of the void spots on struCTural strength by using an X-ray computer tomography (CT) scanner and image-based CAE software.

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This paper describes system reliability of backup systems of power supply networks. The model to optimize installation of backup systems of power supply networks against public facilities to be located in an assumed region was proposed. Adopting the theory in terms of multidimensional optimization, reliability of backup systems to be allocated in the region was defined as the multiplication of the probability of the systems unfailure during their service period, in which disaster risk should be exposed, to the mechanical efficiency of applied backup systems to be necessary to maintain the function of the facilities during the period. In the optimization scheme, its reliability was computed to maximize, constraining economical efficiency when installing the backup systems in addition to the mechanical efficiency. Some case studies were introduced based on the model to show the effectiveness to evaluate the system reliability of backup systems of power supply networks to public facilities.

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In this paper, a brief survey on methods of reliability analysis and design optimization is given. Recent developments in moment based reliability analysis methods are introduced.

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In the heating method it become problem that kowledge of temperature distribution and temperature dependent Young's modulus are necessary. In this paper a method to overcome of the problem for the identification of uniformly distributed resiudal stress is concerned with by introducing an analytical model and by solving the resulting nonlinear least square problem by Levenberg-Marquardt method. The validity of the approach is demonstrated by numerical results.

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We propose a conservative scheme that suppresses numerical oscillation on triangular unstructured grids. We use "multi-moment" that is one of the features of the CIP method. Three types of so-called "moments", defined as the volume-integrated average (VIA), the point value (PV) and surface-integrated average (SIA) of physical field are used as the prognostic variables to be carried forward in time separately. VIA is updated by a flux formulation, and PV and SIA are updated by a semi-Lagrangian scheme. A 2D quadratic polynomial can be construction over a single triangular element. Numerical oscillation is suppressed by limiting the gradient of a polynomial. Shallow water equation is solved by using Method of Characteristics that is suitable for semi-Lagrangian method. The time-integrated average of flux for updating VIA is approximated by the trajectory-integrated average of Riemann invariant. The proposed method has little numerical oscillation and appears to be robust to different numerical grids by some numerical tests.

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