Lumbar segment L3/L4 motion was extracted from a human FE model that had been improved by the authors. Its force-displacement and moment-rotation properties were validated by comparison with experiment results from the literature. Compression and torsion motions of the L3/L4 FE model corresponded to the experiment results. The overall trend of anterior-posterior shear, flexion-extension and lateral bending motions was comparable to that in the experiment but requires further investigation to agree with the experiment results.

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A driving simulator study with thirty-six participants was conducted to clarify the relationships between different time headways (THWs) during car-following and the effects of cognitive distraction on driver response and to investigate the effectiveness of a forward collision warning system (FCWS). Delayed braking response time due to cognitive distraction in critical situations was more obvious when THW was long (4.0 sec) than when it was short (2.0 sec). For SDA, the alarm trigger logic used in this study, relatively early alarm timing led to decreased variation in collision risk, even if there was cognitive distraction when THW was short. This was not the case when THW was long or alarm timing was late.

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We estimated CO2 emissions up to 2050 for India, Thailand, Indonesia, Malaysia, and the Philippines focusing on four measures of CO2 reduction: improving fuel efficiency by introducing fuel-efficiency standards, introducing next-generation vehicles, improving traffic flow, and introducing biofuels. Of these four measures, introducing fuel-efficiency standards reduced emissions the most. In this study’s scenarios, CO2 reduction ratios are 20.0% to 25.7% for improving fuel efficiency above the fuel-efficiency standards, while CO2 reduction ratios are 0.1% to 5.5% for the other three measures.

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[in Japanese]

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Tire wear particles are well known as one of non-exhaust emissions from vehicles. Development of analytical method is necessary to qualify a tire wear particle emission. In this study, thermal decomposition method was used to qualify tire wear particles. Styrene and Limonene produced by thermal decomposition of tire rubber were used as marker substances from tire wear particles. From the result, we decided, thermal desorption temperature of adsorbed gases on tire wear particles was 250℃, and thermal decomposition temperature of tire wear particles was 600℃ to acculately quantify.

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[in Japanese]

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