It is well known that pressure loading and shearing force occur at backrest elevation (BE) of a Gatch bed. Those phenomena are thought to be caused by differences between movements of the body and the backrest during BE, but this theory has not been examined precisely. The simulation of body movement during BE showed that movement of the backrest should be changed according to body size, thickness of the mattress, and lying position. Therefore, we developed a new BE system in which the backrest was connected to the bed body with a rotating arm that lengthened with rotation of the arm and rotation of the backrest. This new BE system could adapt to differences in body size, thickness of the mattress, and lying position. Performance tests of this new BE system using 5 subjects with different body sizes and with 2 mattresses with different thicknesses showed good results similar to those of the simulation. Then, performance of this new BE system was compared with commercially available hospital beds in 12 aged subjects. This new BE system showed a better ratio of loading weight and peak pressure on the back on a comparison between those before and after BE. Furthermore, movement displacement of the weight loading center of the back by BE and slipping displacement of the head after BE were better than those of a commercially available hospital bed.

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Eye tracking studies of older drivers were conventionally accomplished by using a driving simulator. In this study, instead, eye movements of older adults were measured during driving a real car on the course of a driving school. Comparison of five younger adults (age : 27–35) and five older adults (age : 69–80) showed that younger adults looked far ahead and side and back mirrors, whereas older adults concentrated on near front and paid not much attention on side and back mirrors. Older adults were therefore late to pay attention to the objects which could affect driving behavior. On the other hand, sometimes older adults hurried to take an action without enough consideration on the circumstances.

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There are many studies of ejections and most of them are reported from the views of positions and the degrees of injuries in emergency ejections. Also the studies deal with aircrews separately even in two-pilot aircraft in which two pilots control their aircraft as a group. Therefore, this research is performed to investigate pilots’ behavior of ejection focusing on ejections in two-pilot aircraft. Data was extracted from all ejection cases recorded in the Japan Air Self-Defense Force and were analyzed relating to timing of ejection, ejection sequence, communication of ejection between the two pilots. The result shows that it was clarified that the co-pilot’s decision for ejection depends on the aircraft commanders’ direction to eject in cases where co-pilots eject before the aircraft commanders did. Besides, it was observed that the reasons some of the aircraft commanders ejected after co-pilots’ ejections were not only to avoid physical damage like recovery operations, but also to confirm the other pilot’s ejection, as a person in position of responsibility. Some communication problems were also observed in dual ejections cases that are thought to be a peculiar phenomenon to two-pilot aircraft emergency ejections.

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