In order to identify the vibrational characteristics influencing motion sickness in trains, a poll of approximately 4, 000 passengers was undertaken and vibration measurements of each train were conducted on commercial routes. The subject trains were Limited Express on which 14 types of vehicles running on 8 routes were selected. Among them, 8 types were tilting trains with car body tilting systems for curves and the other 6 types were non-tilting conventional trains to be used as a comparison group. In total, data from 52 trains was obtained from all over Japan. The results were then summarized. The rate of passengers who felt motion sickness in tilting trains was higher than those in non-tilting trains. Low frequency lateral motions in the range 0.25 to 0.32Hz highly influenced the degree of motion sickness. Contrary to seasickness, the effects of vertical motion were not shown. There was a wide variation in susceptibility to motion sickness, women and young people were shown to be more susceptible to motion sickness. Traditional frequency weighting curves for evaluating vibrational discomfort were not effective for the evaluation of motion sickness. Consequently, a new frequency-weighting curve to evaluate motion sickness is to be proposed.

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Research on seating comfort has been often conducted in the field of ergonomics. Consideration of differences in the attributes of a person who wishes to sit when he or she chooses a cushion is important. Therefore, focus has been placed on an attribute of body type and a model to predict an appropriate cushion for an individual has been proposed. The relationship between body size and seating comfort has already been in preceding research, and an item for evaluation that is extensively related to overall cushion evaluation is an item related to hardness. In the past, multiple regression was used in a model to indicate the relationship between items for evaluation as expressed in cushion characteristics and overall evaluation as expressed by seating comfort. In the current research, fuzzy logic using non-linearity has been proposed. An experiment for verification was conducted; results indicated a high correlation between predicted values and measured values, and the validity of the system itself was noted. Further progress in research indicated that the model would be highly superior with addition of dummy variables to multiple regression, which is inappropriate, in a conventional subjective evaluation model. Evaluation and examination of both systems were also conducted.

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Personal computer (PC) has spread. However, ordinary QWERTY type PC keyboard is not indispensable in its family-use like as internet surfing and so on. In this study, performance of mobile phone interface is estimated. In the experiments, 10 characters text and 100 characters text were used to input from mobile phone interface and PC keyboard. Input time length and error rate were measured in the experiment. In the result, it is cleared that the mobile phone interface is effective for beginner PC users from viewpoint of input time length in each one key stroke. From viewpoint of error rate, the rate of mobile phone interface is small. It is no more than 1.00%. It is considered that the beginner PC users are able to use the computer, if the mobile phone type interface is realized as a input device.

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In television programs and movies, various switching patterns are used for changing scenes. We conducted a rating experiment to examine the impression made by various audio-visual combinations to clarify the effects of various combinations of switching patterns and sound effects. Sound stimuli consisting of continuous scale patterns (which produce a bright impression) match all kinds of switching patterns. In particular, the ascending scale pattern matches enlarging image, in which a new image expands from the center of the screen. In contrast, the descending scale matches the reducing image, in which the original image is eroded by the new image and is reduced in scale. The obtained congruency between sounds and switching patterns is based on the structural congruency of image pattern and pitch pattern: such as ascending pitch and enlarging image, or descending pitch and reducing image. Furthermore, when the congruency between sound and motion picture is high, evaluation of the audio-visual product is also high. This tendency is based on the cooperative interaction between auditory and visual processing. Sounds and motion pictures should be integrated into a single perceptual unit having a single function in order to produce an impressive effect.

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The objective of this study was to investigate the effects of target shape and size on the operational characteristics of a touch screen. Experimental factors were the target shape (square, SQ; vertically rectangle, VREC; and horizontally rectangle, HREC) and target size (114.3mm², 203.2mm², and 317.6mm²). All the experimental factors were within-subject variables. The right-handed subjects were instructed to use the forefinger of their right hand to point to the target on the touch screen as rapidly as possible while keeping pointing errors to a minimum. The coordinate that they pointed to with their forefinger was measured under all conditions. The pointing accuracy tended to increase with an increase in the target size and was significantly higher for the SQ than for the HREC. About 90% of the points touched were distributed within a square area regardless of the target shape. It was found that the square area was smaller than 12×12 mm², even though the target was larger.

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In order to formulate a universal design for supports for standing passengers, a postal survey was conducted to determine passenger standing positions in long seat type commuter trains, the supports they used and their reasons for using them, and the relation of this data to passenger height. 998 responses were obtained from passengers 60 years old or more and 387 responses from those aged 59 or less. The following became clear. As elderly passengers cannot necessarily always get a seat, the needs of elderly passengers must be considered when designing supports. Elderly passengers use stanchions more than younger passengers. Those who were dissatisfied with the height of straps were less than about 155cm in height. Even those who were taller than 175cm tended to be less satisfied with the height of straps.

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