The constitutive equation based on continuum damage mechanics is formulated for concrete, assuming it as an elasto-viscoplastic damageable solid. Lots of material parameters in the constitutive equation are determined by using the uniaxial compressive test results with the effect of hydration. Some parameters are　age-dependent. The local approach to fracture analysis (the fully-coupled analysis) for the three-point bending tests of notched beams is conducted by using the finite element program with the identified constitutive equation. Material parameters for mortar are identified by the three-point bending tests of beam specimens. Tests of strength recovery by hydration are simulated for notched beam specimens. The validity of the proposed modeling is illustrated by comparing the calculated results with the experimental results.

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  This study purpose is to grope a foreseeing technique of deterioration an electrical insulation performance in suspension-type insulator with salty icicle to evaluate a discharge path using large-scale electrostatic field simulation based on a hierarchical domain decomposition method (HDDM). The whole model of the insulator with accretion icicle is made reality in a wintry testing room. First, we explain a method of making insulator models as objects in the simulation. Then, we explain a calculation method of the discharge path from the simulation results. Finally, we show a result that is compared the simulation result with a result of simple breakdown testing. The icicle accretion insulator models that are used in this study are made to simulate a really environment when occur a breakdown accident due to deteriorate the electrical insulation performance by the salty icicle on the surface; moreover, the 3D CAD models are made based on an actual measuring. These degrees of reproduction natural environments are very high as compared with an accretion model on an only virtual space. The results prove that the discharge path obtained from the electrostatic field simulation is the result to match on high probability as compared with in really breakdown testing.

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  At rifle shooting, some adjustments on a riflescope, called “zeroing”, are required for precise aiming, and done with multiple trial fires. It is a matter of course that more trial shots make zeroing more correctly. However, no conventional data could be found to know how many trials make zeroing how accurately. There are some limits for firing a large amount of ammunition, to know the fact, causing not only budget but legal. Therefore, a distribution of bullet marks is analyzed at the setout, and it is ascertained that follows gauss distribution. Following simulations are based on that fact. Differences between bullet marks and the center of crosshair are normalized with their standard deviation to make relation free from shooter's skills, machining accuracies, and such shooting environments. Required numbers of trial shot are calculated to achieve arbitrary accuracies conclusively.

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  We studied the effectiveness of an approach using Computational Fluid Dynamics (CFD) and multiobjective optimization to investigate the relevance of hemodynamic factors to regulate artery radius at bifurcation region. Five factors were chosen: a) to minimize maximum Wall Shear Stress (WSS), b) to maximize minimum WSS, c) to minimize WSS gradient, d) to minimize WSS temporary gradient, e) to minimize summation of artery radius. We set six combinations of these factors (test cases) which were found trade-off relationship. After performing optimization with CFD in each test case, we compared the optimized shapes with the original shape. Applied this process to seven typical carotid artery bifurcation shapes (actual cases), the relevance of each combination factors was evaluated. As the results, the test case of combination factors of a) and e) was the best, in which the original shape was one of the optimized shapes in all actual cases. In other five test cases, each original shape was not included in the optimized shapes in more than three actual cases. This method differentiated the relevance of selected factors. We confirmed this approach effectively evaluates the relevance of factors to artery bifurcation shapes.

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  Identifying the causes of human responses to risk as evolutionary adaptations could explain observations that cannot be explained by rationality or selfishness. For example, human responses to life-threatening risk can be influenced by the effect on other people in addition to the effect on the individual. This could be explained by the concept of inclusive fitness, which accounts for the evolution of altruism. Even if this adaptation could result from the possibility of death and the benefits for reproduction arising from taking risks, it cannot be experimentally demonstrated. Thus, we use an evolutionary multi-agent model where the altruistic agents are evolved in an environment simulating the risk–benefit trade-off between reproductive advantage and death to show that altruism influences the evolved attitude toward risk. The results suggest that risk-averse attitudes are adaptive when the efficiency of the benefit for reproduction is large enough. In contrast, in a harsh environment where the efficiency of the benefit is small, a risk-prone attitude becomes adaptive. The tendency of human beings to evaluate risks that threaten future generations as high could be explained as this kind of evolutionary adaptation rooted in altruism.

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