Developing public acceptance for a technology that involves some risks is an important step in applying the technology. In developing public acceptance, fostering a sense of security can be stated as the key factor. Although there have been numerous practices for providing safety information in an industrial firm, very few attempts have been made to do so using a scientific approach. Therefore, this study investigated on the manner in which providing safety information affects the level of public sense of security by simulating public relations activities on a nuclear power plant. Seventy-six university students were participated in this experiment as a paid volunteer. The sense of security was measured on three occasions (before informing, immediately after informing, and one and half months after informing), and the changes in the level of sense of security were analyzed. Based on the results, it is concluded that the sense of security has three sub-categories, and each sub-category has different characteristics. The level of sense of security is increased immediately after information was provided and decreased gradually at one and half months after the provision of information.

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Estimation of muscle forces during human motions is important in the fields of sport, ergonomics and bioengineering in order to improve sport techniques, rehabilitation procedures, product designs and work environments, and so on. In general, in the musculoskeletal models that have been developed, the functions of antagonistic muscles and biarticular muscles are not considered to estimate muscle forces. In this study, a musculoskeletal model that considered the functions of the antagonistic muscles and biarticular muscles was investigated. In this model, muscles acting across the hip, knee and ankle joints were treated simultaneously. Furthermore, in this study, vertical jump as dynamic motion was conducted to validate the proposed model to estimate muscle forces. Surface electromyograms (EMGs) of tibialis anterior, gastrocnemius, soleus, rectus femoris, vastus lateralis, semimembranosus, biceps femoris and short head and gluteus maximus were measured to compare with the estimated muscle forces. The experimental results showed that the muscle forces estimated by the proposed method had a good agreement with the EMGs of msucles.

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Many consumer-electronics manufacturers design the buttons of their products such that they have tactile dots and bars on them, which serve as tactile landmarks so that people with visual impairments can use the same products as those used by sighted persons. However, no quantitative data is yet available that enables the determination of the appropriate size and edge radius of curvature of tactile dots and bars to improve the operational performance of consumer products. In this paper, we conducted an experiment to determine the influence of the edge radius of curvature of tactile bars and dots on their tactile discriminability. Young sighted participants tactually discriminated the tactile dots and bars whose dimensions were controlled definitely. Results showed that tactile dots with a larger edge radius of curvature have a higher discriminability (in terms of the discrimination time, accuracy rate, and sureness) than tactile dots with a smaller edge radius of curvature. Furthermore, participants perceived tactile bars with a large edge radius of curvature as a tactile dot when the difference between the length and width of the bar was very small. We conclude that the discriminability of tactile bars depends on the difference between their lengths and widths.

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The aim of this study is intended to present the basic research necessary to transmit graphic tactile information for helping visually handicapped persons, using a small number of stimulated pins. The tactile display developed in this study has an 80-pin array (8×10 pins). A solenoid is used as an actuator for moving the pins upward. By placing the fingers of both the hands, except the thumb, on the tactile display containing the array of active pins, a subject can obtain the information presented on the display. Five blind subjects and 10 sighted subjects participated in this study. First, the optimum condition for the presentation of the images is determined. Next, the correct answer rates of the character information transmission test before and after a preliminary practice session are compared. The result suggests that the tactile sense of the blind subjects is considerably more sensitive than that of the sighted subjects. Moreover, the correct answer rate increased remarkably after the short time preliminary practice session, indicating that the tactile display is an effective medium for the transmission of tactile information.

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