• Journal of Mechanical Science and Technology
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• 제19권spc1호
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• pp.336-342
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• 2005

The DC motor of a vehicle may cause noise and vibration due to high-speed revolution, which can make a driver feel uncomfortable. There have been various studies attempting to solve these problems, mostly focusing on the causes of noise and vibration and a means of preventing them. The CAE methodology is more efficient than a real test for the purpose of looking for various design parameters to reduce the noise and vibration of the DC motor. In this study, a design process for reducing brush noise is presented with the use of a computer model, which is made by using a multi-body dynamics program (DADS). The design parameters to reduce the brush noise and vibration were proposed using a computer model. They were used to reduce the noise and vibration of the DC motor and verified by the test results of the fan DC motor in the vehicle. This method may be applicable to various DC motors.

• 한국도로학회논문집
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• 제19권6호
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• pp.139-145
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• 2017

PURPOSES : This study analyzed the difference in a driver's workload between using a driving simulator and field driving in tunnel, highway. METHODS : Based on the literature review, it was found that a driver's workload could be quantified using biosignals. This study analyzed the biosignal data of 30 participants using data collected while they were using a driving simulator and during a field test involving tunnel driving. Relative energy parameter was used for biosignal analysis. RESULTS : The driver's workload was different between the driving simulator and field driving in tunnels, highway. Compared with the driving simulator test, the driver's workload exhibited high value in field driving. This result was significant at the 0.05 level. The same result was observed before the tunnel entrance section and 200 m after the entrance section. CONCLUSIONS : This study demonstrates the driving simulator effect that drivers feel safer and more comfortable using a driving simulator than during a field test. Future studies should be designed considering the result of this study, age, type of simulator, study site and so on.

• 한국치위생학회지
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• 제12권4호
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• pp.655-663
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• 2012

Objectives : This study was progressed a research with the aim of using it as basic data necessary for a plan in order to increase qualitatively medical level for patients who feel anxiety about dental treatment, and of offering basic data for improving the whole medical services by grasping conditions and satisfaction level with laser therapy in patients who visited dental clinic. Methods : The statistical analysis was carried out t-test and ANOVA by using SPSS(PASW statistics) 18.0. When there is statistically significant difference in analysis of variance, post-test was carried out by using Duncan multiple range test. Results : In therapy kinds of using laser, gingival treatment was the largest with 37.0%. It was the highest in likely seeming to be not painful with 32.9% as for a decisive factor, which came to receive laser therapy, and in having been enough to endure even if having been slightly tingling as for pain level. Conclusions : This study can be considered to have significance in changing recognition of medical cure by surveying patients satisfaction with using laser as a method for slightly solving elements of fear and anxiety about dental treatment and to have its value as basic data for seeking improvement plan for diverse medical services in the future.

• 한국자동차공학회논문집
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• 제13권2호
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• pp.37-43
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• 2005

A haptic steering system which reflects steering reaction torque has been developed for a fixed base vehicle simulator. The haptic steering system consists of a steering effort sensor, MR-clutch, AC servo motor and controller. In order to generate realistic steering torque feel to driver and at the same time to meet real-time simulation requirement, 3D torque map is constructed by experimental data and torque generation algorithm using the torque map has been also developed. 3D torque map is constructed using curve fitting and interpolation of the measured values of the steering angle, velocity and steering torque from actual slalom test on the proving ground. In order to carry out performance test of the developed haptic steering system, a fixed based vehicle simulator is constructed by integrating real time vehicle dynamics module, VR-video/audio module, and the haptic steering system. Steering torque and steering angle curves have been obtained from virtual testing in the vehicle simulator and performance of the haptic steering system has been evaluated.

• 대한기계학회:학술대회논문집
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• 대한기계학회 2004년도 춘계학술대회
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• pp.875-880
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• 2004

The DC Motor of a vehicle may cause noise and vibration due to high-speed revolution, which can make a driver feel uncomfortable. There have been various studies that attempted to solve these problems, mostly focusing on the causes of noise and vibration and the means of preventing them. The CAE methodology is more efficient than a real test for the purpose of looking for various design parameters to reduce the noise and vibration of the DC motor. In this study, a design process for reducing brush noise is presented with the use of a computer model, which is made by using a multi-body dynamics program (DADS). The design parameters to reduce the brush noise and vibration were proposed using a computer model. They were used to reduce the noise and vibration of a DC motor and verified by the test results of a fan DC motor in a vehicle. This method may be applicable to various DC motors.

• 유통과학연구
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• 제14권2호
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• pp.57-63
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• 2016

Purpose - The present study aimed to investigate the difference between entity theorists and incremental theorists in the extent of attributing efforts and traits of consumers for the realization of pursued goals. Furthermore, the present study was conducted to determine the difference depending on circumstances. In this regard, the circumstances where consumers felt pride were divided into those in which important goals and ordinary life goals were achieved. Research design, data, and methodology - An empirical study was performed, which was divided into group 1 and 2. Group 1 is the experimental group concerned with the important goal achievement, and group 2 is the control group related to daily ordinary goal achievement. 80 college students were assigned to each group, respectively. The empirical study for each of the two groups was performed respectively by means of questionnaire survey. In the experimental group, t-test was used to verify the hypotheses for the empirical study. In the circumstances of the control group, t-test was also used to examine whether the results were same as those shown from the analysis of experimental group data or not. Results - According to the group 1 and 2, the t-test of the empirical study showed that entity theorists tended to attribute the achievements of goals to their traits more than incremental theorists did, whereas the incremental theorists tended to attribute achievements of goals to their efforts more than entity theorists did in the important goals-achieved circumstance. In the circumstance of daily life goals-achieved, additional questionnaire survey and analysis were conducted, however, there was no difference between incremental and entity theorists in regard to attributing realization of goals to their efforts, and it leads to assess the difference in the meaning of invested efforts between important goal and ordinary goal achievement. Conclusions - Considering that the feeling of consumers has been regarded as one of the significant factors in marketing mix management, the results of this study are considered as significant implications for management. The implications can be said that when incremental consumers feel authentic pride in the important goals-achieved circumstance, marketers are requested to emphasize the fact that the efforts of consumers have contributed to realization of the important goals. By contrast, when consumers feel hubristic pride in both circumstances, marketers are requested to approach to entity-oriented consumers by way of trait. Authentic and hubristic pride are pervasive and engendered by important events or daily routines, and they could have effect on delaying making decisions. Therefore, it is necessary for future research to examine the unexplored difference of effect between incidental authentic and hubristic pride on consumer's self-control. In particular, future researches are related to the extent of difference in attributing efforts and traits. The consumers'realization for the previously pursued goals between entity theorists and incremental theorists affects their present or long distant decisions in self-control dilemmas. The consumers are faced with choosing one between virtuous long term- related option and vice immediate option.

• 대한간호학회지
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• 제26권4호
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• pp.833-852
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• 1996

Regular long term dance movement could be one of ways to induce improvement of psychophysiological variables, resulting in improvement of quality of life. However, there have been few studies to evaluate the effect of dance movement training on both physiological and psychological variables in the elderly. This study was focused to determine the effect of Korean traditional dance movement training on psychophysiological variables-body weight, body fat, lean body mass, muscle strength, muscle endurance, flexibility, agility, resting heart rate and blood pressure, depression and life satisfaction-in Korean elderly women. Thirty four subjects, aged between 65 and 75years who have normal cognition, sensory function, cerebellum function, cardiovascular function, participated in this study. Seventeen experimental group subjects were selected from E-elderly university in Kyung Gi province, and Seventeen control group subjects were selected from N-welfare facility in Seoul City. Seventeen experimental group subjects participated for 12weeks dance movement program. Korean traditional dance movement program was developed on the basis of Korean traditional dance and music by the author. The program consisted of approximately 50minutes of dance, 3times a week for 12weeks. During 50minutes workout, there were 15minutes of warm-up dancing, 25minutes of conditioning dance and 10minutes of cool-down dancing. The intensity for the conditioning phase was at between 60% and 65% of age-adjusted maximum heart rates. The body weight, body fat, lean body mass, muscle strength(grip strength, leg strength), muscle endurance, flexibility, agility, resting heart rate and blood pressure, depression and life satis-faction were measured prior to and following the experimental treatment. The participants in dance movement were interviewed focusing on subjective feeling following 12 week's regular dance movement. Data were analyzed with mean, standard deviation, percentage of change, X²-test, t-test, and ANCOVA test using SPSS PC/sup +/ program. Subjective feeling was categorized into cognitopsy-chological and physiological responses. Results were obtained as follows : 1) The body weight (F=15.52, p=.000), body fat (F=18.33, p=.000) and lean body mass (F=7.28, p=.011) of the experimental group were significantly lower than those of the control group following the dance movement training. 2) The leg strength (F=30.96, p=.000), muscle endurance (F=9.06, p=.005), agility(F=44.92, 000), flexibility(F=6.84, p=.014) of the experimental group were significantly higher than those of the control group following the dance movement training. There was no significant difference of grip strength(F=.43, p=.515) between experimental and control groups. 3) The heart rate(F=26.96, p=.000), systolic (F=10.40, p=.000) and diastolic(F=3.99, p=.005) blood pressure at rest of the experimental group were significantly lower than those of the control group following the dance movement training. 4) No significant difference of score of depression (F=3.49, p=.071) was observed between experimental and control groups. 5) Score of life satisfaction of experimental group was remarkably higher than that of control group following 12weeks of dance movement training (p<0.05). 6) Thematic responses about the dance movement following the training were positive. "I feel good" was the most frequent among cognitopsychological responses and "I feel lightness of body" was the most frequent among physiological responses. The results suggest that Korean traditional dance movement training can improve psychophysiological variables of Korean elderly.

• 한국항해항만학회지
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• 제32권1호
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• pp.15-22
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• 2008

바다에서 운항하는 선박은 바람과 파도 등의 외란 때문에 횡동요(Rolling), 종동요(Pitching), 상하동요(Heaving) 등의 운동을 하게 되며, 이러한 운동은 가속도 형태로 승객이 느끼게 된다. 따라서, 선박내의 특정 지점에서 좌우방향, 상하방향 가속도와 각속도 등을 계측하면 선원 또는 승객이 선박 운동에 어느 정도 피폭되었는가를 알 수 있다. 본 연구에서 개발한 운동 운항환경 모니터링 시스템은 4개의 가속도계와 가속도계, 자이로가 포함된 관성 자세계측장치, 데이터 취득장치를 포함한 계측 및 통신부, 중앙에서 데이터를 관리하고, 운항환경 지수를 계산하는 전산기로 구성되고, 계측된 가속도와 각속도를 이용하여 운항환경을 나타내는 정량적 지수인 뱃멀미 지수(Motion Sickness Incidence, MSI), 운동유발 작업방해회수(Motion Induced Interrupt, MII)를 실시간으로 계산한다. 개발된 시스템은 한국해양대학교 실습선인 한나라호의 부산-목포, 부산-제주 연안항해시 실선시험을 통하여 유효성을 확인하였다.

• 한국안광학회지
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• 제14권2호
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• pp.53-59
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• 2009

목적: 부산지역 중고등학생을 대상으로 시력과 안경사용에 대한 실태를 조사하였다. 방법: 4개의 개별학교 중고등학생 821명에 대해 2007년 7월에 설문 조사하였다. 결과: 74.3%가 시력 저하자이며, 66.26%가 안경을 착용하였다. 시력 저하자중 안경 미착용자는 13.77%이며, 안경 착용자중 15.26%가 시력 저하자였다. 안경을 착용하지 않는 이유와 안경을 교체하지 않는 이유는 생활에 불편을 느끼지 않았기 때문이라고 답하였다. 결론: 많은 학생들이 제한된 근거리 생활환경으로 인하여 시력이 나쁨에도 불구하고, 안경 미착용에 대한 불편함을 느끼지 않는 것으로 보인다.

• 디지털산업정보학회논문지
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• 제10권2호
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• pp.173-186
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• 2014

There are a variety of alternative products in the computer markets. A tablet PC, which is a small type of computer, is expanding its market share as an independent type of computer products. The purpose of this study is to find out what the factors are that led to the success of the tablet PC. A research study was carried out on the intention to use of tablet PCs by consumers. The factors that affect the intention to use of tablet PCs users were structured on the basis of attitude theory. According to the one-dimensional theory of attitude, cognitive factors affect the affective factors, which in turn affect conative factors. In the study, the relations between each dimension were set up. The hypothesis was tested by structural equation modeling. The test results are as follows. First, the values and satisfaction that the owners of tablet PCs feel from the products and the positive comments on the products from their nearby acquaintances affect in a positive way how much they like their products. Second, the products surrounding the tablet PCs did not affect the intention to use of the products. Third, the product favorability that the owners of tablet PCs feel affects the intention to use in a meaningful way. The results of the research also show that hi-tech products such as tablet PCs affect their attitude after they buy and use the products. This attitude affects intention to use of the products. The managers of companies that produce hi-tech products should consider the cognitive and affective aspects of the product owners when manufacturing and marketing products.