Past Issues

The study figured out the operational conditions of a two-way movement actuator made of one-way shape memory alloy (OWSMA) for versatile ventilation intelligent garments. To develop a low-power actuator that consumes energy only when a garment changes its form such as opening and closing, multiple channels of OWSMA were used, and optimum diameter of the wires was examined. For the switch device, optimum voltage application unit time was determined. Optimum diameter of OWSMA wire was determined by applying 3.7V to the pre-determined candidate diameters, which demonstrated two-way operation in previous studies. In order to evaluate the optimum voltage application time, the internal diameter of the actuator was measured while increasing and decreasing by 50 ms from the unit time of voltage application. Delay time under two-way operation of the actuator was measured to minimize interference caused by heat between channels. Power of 3.7V was applied to OWSMA for assessment of optimal time, and the whole process from heating to cooling was video-recorded with a thermal image camera to determine the point of time at which the temperature of OWSMA wire dropped below the phase transformation temperature. The results showed that 0.4Φ was the most suitable diameter, and the optimum unit time of voltage applied to open and close the actuator was 4100ms. It was also shown that the delay time should be more than 1.8 seconds between two-way operations of the actuator.

keyword : Shape Memory Alloy, Bi-directional Actuator, Low-power Consumption, Voltage Application Time, Versatile Ventilation Intelligent Garment, 형상기억합금, 양방향 작동 액추에이터, 저전력 소비, 전압인가시간, 가변통기성스마트의류

The purpose of this study was to investigate the visuo-spatial attention ability and the emotional perception ability of people across the normal range of the scores on the bipolar disorder scale. The Korean version of the Mood Disorder Questionnaire (K-MDQ) was used to measure the bipolar disorder tendency of normal people. A useful field of view (UFOV) task and an emotional perception task were used to measure visuo-spatial attention and emotional perception ability, respectively. The participants did not have any mental illness history or other medical problems. The participants were divided into three groups according to K-MDQ score (low, normal, and high), and their performances were compared. In the UFOV task, the high K-MDQ score group had lower level of performance than the other groups, suggesting that a high bipolar tendency is associated with reduction of visuo-spatial attention ability. In the emotional perception task, the group with the high K-MDQ score showed higher perception of negative emotion bias than the other groups, suggesting a high bipolar tendency to associate with reduction of emotional perception ability. These results suggest that visuo-spatial and emotional attention abilities are related with bipolar disorder tendency even in the normal population.

keyword : Bipolar Disorder Tendency, Emotional Perception Ability, Self-report Inventory, Visuo-spatial Attention Ability, 시공간 주의집중력, 양극성 장애 경향성, 자기보고형 검사, 정서 지각 능력