In this study, the masking effect of olfactory stimulus on the awakening state due to sound stimuli while driving using Graphic Driving Simulator was observed through the response of autonomic nervous system. The test was conducted for 11 males in their twenties. The siren of ambulance car was presented to them as auditory stimulus for 30 secs while driving in a situation of high way in the condition of both peppermint and control, respectively, and LF/HF ratio of HRV (Heart Rate Variability), the activity index of sympathetic nerve, and GSR (Galvanic Skin Response) response were examined. The test was proceeded in the order of three stages, that is, sound stimuli (test 1), driving performance, and sound stimuli (test 2), and fragrance stimulus, driving performance, and sound stimuli (test 3), and the physiological signal of GSR, HRV was measured in the whole stages. As a result of test, comparing the results of before and after auditory stimulus test (1) (p < 0.01), test (2) (p < 0.05), and test (3) (p <0.01), driving performance test (2) (p < 0.01), test (3) (p < 0.01), and olfactory stimulus test (3) (p < 0.05), respectively, GSR response increased, showing significant difference in all the tests. It indicates that when auditory stimulus was presented to the subjects, they were in the awakening state as sympathetic nervous system got activated. As a result of comparing auditory stimulus while driving before and after presenting olfactory stimulus, there was no significant difference in GSR response. The LF/HF ratio of HRV increased, showing a significant difference only in test (2) (p < 0.05), and in driving performance test (2) (p < 0.05) in auditory stimulus, however, it showed no significant difference in olfactory stimulus. As a result of comparing auditory stimulus while driving before and after presenting olfactory stimulus, there was a decrease, showing significant difference (p < 0.05) in LF/HF ratio of HRV. That is, it means that the activation of sympathetic nervous system decreased, and that parasympathetic nervous system got activated. From these results, it was observed that while driving, the awakening level due to auditory stimulus was settled with olfactory stimulus. In conclusion, it was drawn that while driving, olfactory stimulus could have the masking effect on auditory stimulus.

In this study, it was observed through the ability of performing secondary tasks and baseline fetal heart rate how the supply of lavender, peppermint and highly concentrated oxygen (40%) affected distraction due to the performance of secondary tasks in the driving environment. Twelve male university students conducted secondary tasks while driving in the environments (6 in total) mixed and designed with oxygen concentration (21%, 40%) and the condition of odors (Normal, Lavender, Peppermint). The test was proceeded in order of stable state (5mins), driving (5mins), and secondary tasks (1min), and by extracting ECG data from every section by 30secs, the mean value of baseline fetal heart rate was calculated. As a result of analysis, in the ability of performing secondary tasks, a percentage of correct answers showed no difference in oxygen concentration and the condition of odors (p > 0.05). In performance completion time, a percentage of correct answers decreased showing a statistically significant difference in the condition of odors compared with the condition where odors were not provided (p < 0.05). As for baseline fetal heart rate, in the comparison between sections, while performing secondary tasks, it increased showing a significant difference compared with stable state and driving state (p < 0.05). The effect of interaction was observed in oxygen concentration and the condition of odors. When odors were not provided, baseline fetal heart rate decreased in 40% oxygen concentration compared with 21% oxygen concentration (p < 0.05), however, when peppermint was provided, it increased in 40% oxygen concentration compared with 21% oxygen concentration (p < 0.05). In conclusion, the fact that the condition of odors increased the ability of calculation, and when only the highly concentrated oxygen was provided, parasympathetic nerve system was activated, however, when highly concentrated oxygen was provided with peppermint at the same time, sympathetic nervous system (sns) was activated, which had a negative effect on the autonomic nervous system was drawn.

The purpose of this study was to examine drivers’ driving behaviors and eye-movements according to driving speed and navigation-position while operation of the navigation in driving. For this purpose, two driving conditions (low-speed and high-speed) and

본 연구는 자동차 시뮬레이터에서 운전 중 제시된 후각 자극이 외부에서 제시된 청각자극의 각성 상태에 대한 마스킹 효과를 자율신경계 반응을 통해 알아보고자 하였다. 실험은 20대 남성 11명을 대상으로 하였고, 향 자극은 peppermint를 제시하였다. 청각자극은 구급차 싸이렌 소리를 70~75db의 크기로 30초 동안 제시하였다. 자동차 운전 상황은 편도 3차선의 한적한 도로를 주행하였고 자율신경계의 반응은 피부반응(GSR: Galvanic skin Response)의 변화를 살펴보았다. 실험결과 control, 운전수행, 후각 자극 중 운전 수행, 각각에서 청각 자극 제시 전,후 비교는 모두 유의차(p＜0.05)를 보이며 제시 후가 증가하였고, 각각의 청각 자극 후의 비교는 유의차를 보이지 않았다. control, 후각 자극, 각각의 운전수행 전,후 비교는 모두 유의차(p＜0.05)를 보이며 후가 증가하였고, 각각의 운전수행 후의 비교는 유의차를 보이지 않았다. control과 후각자극의 비교는 유의차(p＜0.05)를 보이며 후각 자극 시 증가하였다. 위와 같은 결과는 후각 자극이 운전수행중 청각자극으로 인한 각성 수준에 영향을 주지 못함을 의미한다. 즉 후각 자극이 청각자극에 대한 마스킹 효과가 일어나지 않음을 시사한다.

본 논문에서는 평판 두께 방향의 선형 및 비선형 응력 분포를 일정한 크기의 단순응력 상태로 가정하는 분할판(Two-element plate) 개념을 이용하여 비선형 특성을 나타내는 평판의 강도해석을 할 수 있는 Reissner 범함수와, 재질 특성은 선형이면서 기하학적 비선형 특성만을 갖는 평판의 강도해석을 할 수 있는 변형 Reissner 범함수를 모델링하였다. 두 종류의 Reissner 범함수들을 근거로 하여 축방향 하중을 받는 평판의 선형 좌굴과 좌굴후의 비선형 특성 및 최대강도들을 계산할 수 있는 유한요소 방정식과 프로그램 개발을 시도하였다. 개발한 프로그램을 이용한 수치해석 결과, 분할판 이론을 사용한 선형좌굴해석 결과가 기존의 평판이론을 사용한 선형좌굴해석 결과와 유사항 경향을 나타냄으로써 분할판 이론에 근거한 유한요소법을 하중과 경계조건 및 구성재질이 다양한 일반적인 평판의 강도해석에 확대 적용함은 물론 좌굴후 비선형재질 특성으로 인한 평판의 최대강도도 예측 가능하다고 생각한다.

컴퓨터 세포동결기를 이용하여 생쥐 배아를 동결할 때 액체질소 (L)의 분사속도가 해빙 후 배아의 미세구조, 기능 및 발달에 미치는 영향을 알아보고자 하였다. 이를 위해 배아는 동결을 하지 않은 대조군 (control) 및 동결군에서 L의 분사속도에 따라 고속분사군 (120 infusion/min group 1), 저속분사군 (50 infusion/min; group 2)으로 나누었다. ICR 계열의 생쥐의 2 세포기 배아를 사용하였으며, 동결 및 해빙은