We established a method to analyze the psychological response to local hot water stimuli in order to better understand the human psychological response to taking a shower. Our analysis involved a categorized evaluation scale of thermal sensation to local hot water stimuli. We examined whether categories were at regular intervals or not. We then discussed differences in psychological response to hot water stimuli between males and females using the Akaike Information Criterion. The relationship between the objective physical hot water stimuli and subjective psychological response was determined quantitatively using the so-called membership function in the fuzzy set theory. The degree of fuzziness existing in the subjective judgment was then evaluated using the concept of fuzzy entropy. The following results were obtained; (1) Categories of thermal sensation were at regular intervals. (2) Males showed a lower tolerance of heat than females. Males were more susceptible to heat sensation than females.

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The purpose of the present study is to investigate the technical requirements that are necessary in order to realize a bathing system that is both safe and easy-to-use for both the care receiver and the care provider. In addition, the present study seeks to clarify the physiological and psychological responses of the care receiver while using the proposed system for showering. The proposed system is referred to as the “systemic showering system.” The present paper discusses the basic required components of the systemic showering system as well as an experimental system which was constructed in order to examine various aspects of the proposed system. The proposed system was designed from the viewpoint that the care receiver, the care provider and the showering machine should form a man-machine system that provides favorable interaction, rather than concentrating only on the design of the machine while ignoring the human element. The experimental system is comprised of a laboratory that is partitioned into a dressing room and a bathroom, a showering machine, and a stretcher that has an attitude control mechanism that is powered by a hydraulic drive. The air temperature of each compartment is controlled independently within the range of temperatures that are normally encountered in everyday life. The proposed showering machine allows the special hyperthermia state that originates in the closed structure of the body of the machine to be surveyed, and the showering conditions can be set independently for different parts of the subject's body, i.e. limbs, trunk, etc. Stable steady-state characteristics and transient responses with respect to regulating water temperature and water flow rate during showering were confirmed by control experiments. In addition, the physiological responses of the subjects and the effects on the bathing conditions due to the interior temperature of the showering machine during showering were examined experimentally.

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An aircraft dynamics refined in aerodynamics is unstable and then such an aircraft is normally stabilized by automatic flight control systems. The pilot's control system for the aircraft with automatic flight control has two method. One is pitch command/attitude hold system which gives pitch attitude response to control stick deflection. Another is rate command/attitude hold system for pitch rate response to control stick deflection. In this paper, handling qualities to the two pilot's control methods are discussed experimentally using a fixed base simulator. The results are shown that the handling qualities of the aircraft with the rate command control system are inferior to that of the attitude command control system, but the qualities of rate command control system can be improved by the addition of the shaping filtere.

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The purpose of this paper is to identify the relationship between the degree of discomfort of passengers/crew and the floor tilt angle when trains are at a stop on curved sections with cant (bank). An experiment was performed with a mock-up vehicle. Subjects on board the vehicle evaluated the degree of discomfort due to floor tilt. The range of tilt angle were 0 to 12 degrees at the interval of 2 degrees. Taking into consideration the popular posture or behavior of passengers/crew in coach, the following four type conditions were adopted; seated, standing, walking and handling selling service cart. In the experiment of walking condition, the influence of difference in shoe types was tested. Results of the experiment are as follows. Ratings of seated/standing subjects are more severe than walking and cart handling subjects who are in motion. The type of shoes affects the rating of easiness to walk, but does not affect the discomfort due to tilt. The degree of discomfort of cart handling condition worsens rapidly when the floor tilts over 6 degrees. On the basis of these results, regression expressions are proposed using the tilt angle as an independent variable and the discomfort rating as a dependent variable.

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An underwater bicycle ergometer was developed for the exercise of obese persons, persons in need of physio-therapy, individuals with low physical fitness or persons who need post-operative rehabilitation. A wheel with four fans on a load was constructed (called the ergometer). The intensity of the movement of the fans depends on the rotation speed. Three experiments were done, one using only the upper limbs, one only the lower limbs, and one experiment with all four limbs. It was seen that, when the exercise was done, under all the three conditions both the oxygen uptake and the heart rate showed a linear increase together with an increase of the rotation speed of the ergometer. The highest value was shown when exercise was done with all the four limbs, next is the exercise with the lower limbs and last was the exercise done with the upper limbs. Furthermore, the RPE (Rating for Perceived Exertion) showed a tendency to be lower when doing the exercise with four limbs compared to when doing the exercise with only the upper limbs or only the lower limbs. By doing the exercise with all the four limbs the cardio-respiratory system is used in its most efficient way. Since it is possible when using the present equipment to choose a free way of exercise, it is expected that excessive strain on the body can be avoided.

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Two types of questionnaires which forecast ‘operational procedure’ and ‘button function’ are proposed on this study as the methods for evaluating procedural usability of button type terminals as remote control units. The effectiveness of these two methods were examined through user tests with an actual remote control unit of an air condition system. Two transactional charts obtained by the results of the questionnaire of ‘operational procedure’ and ‘user tests’ were compared. Right forecast ratio was calculated on each button with the questionnaire of ‘button function’. It turned as the results that operational procedures were varied after subjects' operation of the button of the low ratio of right forecast of the button function, and that this tendency was observed at both the questionnaire and the user tests. However, as repetition entries of a button, which were observed at user tests, were not observed at the questionnaire of operational procedure. It seems, therefore, there exist some limitation as the usability evaluation methods of the questionnaires proposed in this study.

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