It was examined the water repellency and sliding characteristics for the water of the seats when the ratios of fine salient and reentrant on the silicone-based seats were changed. It is made clear that the both characteristics were superior in the case of about 1/6, the ratio of salient length and the reentrant length and that the low-drag surface in water did not become necessarily superior even if superior in water repellency. The reduction effect of fluid friction coefficient on the wall surfaces pasted the sheets with super low-drag surface in water was examined. It is made clear that there was few the reduction effect in the turbulence region.

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We report about new turbo-compound system for small-sized gasoline engines. Recently, Global warming problem of CO2 emissions is worldwide issues. One of solve to this issues are low CO2 emission vehicle as EV, HEV and Turbo-compound. However, these systems are more complex and weight. Therefore, we have manufactured Simple Turbo-compound for small sized gasoline engines.

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The present study investigated the effect of boost pressure and EGR rate on the operation of a small single cylinder DI diesel engine fueled by coconut oil methyl ester (CME). The boost pressures were varied from 100 kPa (naturally aspirated condition) to 130 kPa with a Roots blower type supercharger and the oxygen concentration of the intake air were changed from 21 to 16.9% using a cooled EGR technique. The results show that compared with standard JIS No. 2 diesel fuel, the trade-off relation between the NOx and smoke emissions of the CME improved remarkably at high EGR rate conditions with supercharging.

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This article examines the optimal control method of active suspension systems. Performance required in the suspension is the driving stability and ride comfort. It is well-known that there is a tradeoff between those two performance criteria. Active suspension has been attracting attention as a mechanism to cope with both ride comfort and driving stability. Even if the active control strategy is used, the tradeoff between the acceleration of the body (related to the ride comfort) and the suspension stroke (related to driving stability) still exists. In this study, we propose a new gain scheduling control method to overcome the tradeoff, that is, some fixed active controllers are scheduled depending on the sensor information to capture the state of the suspension system. The sensor information is used for the interpolation of those fixed controllers. To get the good interpolation parameter, a neural network (NN) is adopted. Various parameters in the NN are optimized with a genetic algorithm.

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In this paper, we deal with a semi-active control of structural systems based on a positive real active control law. It is well known that the range of the phase difference of the positive real controller is limited between ±90 degrees. The phase property of the positive real control is favorable as the reference active control law for the semi-active control because the active control force generated by the positive real active controller can be reproduced with more precision than the case when the reference active control without any phase constraints are used as the reference active control law. The positive real controller with a constraint on the closed-loop H_2 norm can be obtained by solving a sequence of a LMI problem that is an approximation of a BMI problem. The semi-active control law is obtained based on the control force of the output signal of the positive real controller. A simulation study is carried out for the 3-dof structural model of the benchmark building of NCREE in Taiwan. We show that the control force of the semi-active control is close to that of the active control law when the positive real reference control law is adopted. By comparing with the case of sky hook control, the advantage of the proposed semi-active control method is presented.

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In this paper, we examine the semi-active control of structural systems with an inertia damper (Inerter) and a magnetic responsive Gel (MR gel). The inerter generates the resistance force proportional to the relative acceleration between points that the inerter is installed. In the present study, we assume that the inertia coefficient of the inerter can be changed according to the command signal in real time. The MR gel has variable damping and stiffness characteristics that can be changed with a magnetic field around the gel. With those two variable devices, a semi-active control law based on the predicted control output and the real-time simulation of multi models of structual systems is proposed. The performance of the semi-active control is evaluated with the simulation for a single and two degree of freedom structual systems subject to earthquake disturbances. The effect of the dynamic delay for the command signal of the semi-active control devices is assessed.

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Improving sports skills requires many repeated practice, and it is important to understand difference between the ideal body motion and their motion. Currently, there are several methods to check the body motion by using mirrors or video cameras. However, these conventional methods have problems such as occurring invisible body places caused by fixed viewpoint. Our study group has proposed a new training support method called a self-coaching system. This self-coaching system is to show clients the reproduced motion of a humanoid robot, which mediates in virtual contact to improve their motion by themselves. This study evaluates the effectiveness of that training support method in the case of underhand pass movements of volleyball.

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