The present study aims to establish comprehensive test methods to evaluate the mechanical properties of the intravascular coronary stent with a closed cell design. We focused on three important mechanical properties required to the stent, bending flexibility, radial strength, and longitudinal strength. Test apparatuses and testing procedures were then developed for precise evaluation of those properties. It was found that the developed test apparatuses and testing methods successfully evaluated the mechanical properties of the stent. The results revealed that the mechanical properties were strongly influenced by the structure of the stent, that is, combination of the cell strut and the link strut.

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The attendant operated wheelchair is propelled by applying forces to handles at the back of the chair. However, very few published data justify the design of the push handles on existing wheelchairs. The aim of this study was to analyze the external forces and biomechanical loading on the upper limb system during wheelchair pushing, in relation to different push handle heights. Recommendations for wheelchair pushing in accordance with push handle height were also made. Five subjects carried out two different wheelchair transport tasks (up and down a ramp, pitch angle: 4°) at three different push handle heights. Data on the dynamic positions of the upper limbs were obtained from a motion capture system. To estimate net moments on shoulder and elbow joints, a dynamic two-dimensional linked segment model was used. The lowest maximum net joint moment at the elbow joint was observedat a normalized handle height of 84% for transport in the upward direction and at a normalized handle height of 92% for transport in the downward direction. To minimize the strain on the upper limbs, the optimal handle height is the height that minimizes the elbow net joint moment, which would be a normalized handle height around 90%.

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The wheel-typed vehicle with crawlers in between front and rear wheels has been developed in order to move swiftly on both soft ground and pavement. In this study, the mechanical model of this vehicle was presented. The vehicle traveling performance on the dry sand was evaluated by the simulation and the traveling test. It was cleared that the traveling performance of the vehicle was larger than in the case of only the wheels on the dry sand.

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A large amount of tsunami sludge was generated by the 2011 off the Pacific coast of Tohoku Earthquake, and the radiation contamination due to the nuclear power plant disaster also became a serious problem. It was necessary to decontaminate the radiation-contaminated waste and soil, and the radioactive pollutant will be stored at temporary storehouses. In this study, the relationship between failure strength property and permeability of the cover soil made of tsunami sludge was experimentally investigated.

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In this study, the cover soil for radiation-contaminated soil was made of tsunami sludge by applying Fiber-cement-stabilized soil method, and the durability for drying and wetting of cover soil was experimentally investigated. It was confirmed that cement-stabilized soil produced by the conventional method deteriorated with increasing the cycle number. However, Fiber-cement-stabilized soil did not deteriorate at all and showed high durability for drying and wetting regardless of the increase of cycle number.

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Soil contamination is one of the main environmental issues. Insoluble treatment is an important method to improve contaminated soil. In order to solve the problems of insoluble treatment, a simulator to represent the interaction between solid and liquid was developed using Smoothed Particle Hydrodynamics (SPH) method. The simulator replicated a water flow with an error rate of 2% and a permeability test with an error rate of 4%. For water absorption into dry silica sand No.9, the simulation result became more realistic by concerning soil suction.

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This study focused on excavating force by a narrow soil cutting blade. Excavation test was performed to measure the excavating forces, and the experimental results were compared with the excavating forces estimated by geometric models proposed previously. The estimated error was up to 860%, which was caused by failure patterns. To modify the previous model, the failure patterns were quantified by representing the patterns as the size of the aggregates of disturbed soil. Considering a relationship between estimated error and the size of failure region, the estimated error was within 76%.

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