[in Japanese]

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 This paper proposes a method to reduce the computational complexity with little influence on the evaluation results after clarifying the factor of computational load of simulations of the Multi-Class Zone ITS information communication method.
 In ITS information communication for the purpose of safety, it is important to communicate successfully between vehicles that are highly likely to collide. However, communication evaluation methods irrelevant to such collision risk is often used.
 In consideration of such situations, we employed ahead of the world the new method of the communication success probability between high risk vehicles such as the distance between the centers of the vehicles is within 5 m and within 2s. However, it has been a problem that the computational load of simulations for communication performance evaluation is high.
 In this paper, we analyze the computational complexity of performance evaluation in simulation, and we propose an acceleration method of simulation after clarifying causes of computational complexity. Results show that the simulation speed can be accelerated about 1.2 times at 8 vehicles/km/lane or 5.0 times at 55 vehicles/km/lane in comparison with the conventional method, and from the viewpoint of whole simulation, proposed method achieved about 4.5 times faster than conventional method.

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 Multi-agent systems are often used in evacuation simulation. The agent needs to be modeled to include psychological factors of evacuees. The following behavior, which is one of the major psychological factors, is defined as the behavior to follow other persons when he/she does not know where to evacuate. While the following behavior is known as the risk of inducing wrongly directed evacuation, it may expedite the evacuation by chaining a group of people to a right direction. The effects of following behavior are, however, almost unknown at the city level.
 In this paper, the agent model with the following behavior is introduced and evaluated its property at the city level. Also, two models of “path memory” and “follow-up promotion behavior” are proposed as countermeasures against the property of evacuation delaying caused by the following behavior.
 Through the evacuation simulation experiments assuming the tsunami disaster, it is shown that evacuation speed depends on the ratio of the agents who know an evacuation spot. Also, we show that “path memory” accelerates the evacuation behavior when few surrounding agents have knowledge on the evacuation spots as well as “follow-up promotion behavior” shows the same tendency when several surrounding agents have the same knowledge.

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  Along with the diffusion of electromagnetic field analysis using computers, a large-space including complex shapes also becomes an analysis target, and development of a high-accuracy analysis is required for these problems. Therefore, in this study, Berenger's PML, which is currently the most effective absorption boundary condition, is applied to the parallel finite element method based on the domain decomposition method and it is effective as an analysis method of the microwave band. As a basic study, we developed an analysis solver using parallel finite element method based on iterative domain decomposition method. As the accuracy verification of the analysis solver, we analyzed TEAM Workshop Problem 29 which is a benchmark problem, and confirmed that a highly accuracy solution is calculated. Next, a model with PML added to the dipole antenna is used as an analysis object, and the absorbing performance of PML is evaluated by using reflection coefficient based on S parameter. Moreover, by comparing the directivity of the dipole antenna with the theoretical solution, accuracy evaluation in the antenna analysis. As a result, we confirmed the effectiveness of this method for microwave analysis, so we report here.

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 The purpose of this research is to design a locomotion controller for a snake robot with detecting and inhibiting side-slip. A state-space representation form of the snake robot is described to deal with side-slip without any model switching. A locomotion controller with an observer is designed based on State Dependent Riccati Equation strategy using the state-space form. As a result, the snake robot arrives at a target point inhibiting side-slip. The validity and effectiveness of the proposed method is verified through numerical simulation.

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