• Journal of the Korea Society for Simulation
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• v.19 no.1
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• pp.133-141
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• 2010

This research suggests a unified scheme for using stratified sampling and control variates method to improve the efficiency of estimation for parameters in simulation experiments. We utilize standardized concomitant variables defined during the course of simulation runs. We first use these concomitant variables to counteract the unknown error of response by the method of control variates, then use a concomitant variable not used in the controlled response and stratify the response into appropriate strata to reduce the variation of controlled response additionally. In case that the covariance between the response and a set of control variates is known, we identify the simulation efficiency of suggested method using control variates and stratified sampling. We conjecture the simulation efficiency of this method is better than that achieved by separated application of either control variates or stratified sampling in a simulation experiments. We investigate such an efficiency gain through simulation on a selected model.

• Science of Emotion and Sensibility
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• v.12 no.2
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• pp.181-192
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• 2009

The purpose of this study was to explain the attitudes and acceptance toward the smart clothing adopted by the TAM(Technology Acceptance Model). A theoretical model on consumer acceptance of the commercialized smart clothing was constructed on the basis of previous studies and a review of literature and tested the path analysis. For the data analysis, statistical methods of confirmatory factor analysis, correlation, and covariance structural analysis using AMOS 5.0 package were employed. The results from a web-based survey of 557 online consumers indicate that the TAM by Davis(1989) adopted by perceived value according to market price was able to explain consumer acceptance of smart clothing substantially well. Using structural equation modeling, eight of the six hypotheses investigated in this study were supported. The results of the testing of the hypothesis were as fellows: First, perceived ease of use had a side effect on attitude through perceived usefulness. In addition, the attitude was found to affect consumer acceptance. Second, perceived usefulness was found to affect consumer attitude on perceived value, however, had not significant effect on consumer acceptance toward smart clothing. Third, perceived value was found to affect both consumer acceptance and attitude toward smart clothing. Finally, the attitude toward smart clothing had a direct effect on the consumer acceptance.

• Journal of the Korean Society for Library and Information Science
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• v.56 no.4
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• pp.239-267
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• 2022

In this study, the adolescents' perception of the Information Search Process(ISP); their anxiety and the need for intervention during the process were investigated based on Kuhlthau's ISP model, and the relationship among the factors was analyzed with structural equations. In addition, the effectiveness of scaffolding strategy to the experimental group during the class was verified. The main findings are as follows. First, as a result of exploring the anxiety felt by learners and the need for intervention in the information search process, it was found that the presentation stage had a significant effect on the anxiety, and the collection, presentation, and assessment stages had significant effects on the need for intervention. Second, as a result of controlling each variable to investigate the anxiety felt by learners and necessity of intervention in the information search process, it was confirmed that among the demographic variables, the difference between the first graders and the second ones was significant; and the difference in the metropolitan area was more significant than that in the Gangwon province. Third, as a result of paired t-test and covariance analysis on the control group and the experimental group, it was confirmed that the anxiety and need for intervention of the experimental group were statistically significantly reduced. The significance of this study lies in the point that it presents a practical basis for applying scaffolding strategies appropriate to information search process in the field of education.

• Journal of Digital Convergence
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• v.15 no.7
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• pp.329-342
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• 2017

This study investigates convergent influence on Self Factors(SF), Stress Factors(STF), Resilience & Control Factors(RCF), Test Anxiety(TA), Learning Flow(LF) and academic burnout among Health College Students in TOEIC class(HCST). The survey was administered to 291 HCST from 1 college located in J area during the period from April 3, 2017 to April 14, 2017. The structured self-administered questionaries were used. With the analysis of covariance structure, we could confirm relationship among the six factors such as SF, STF, RCF, TA, LF and academic burnout. The results of the study indicate that the efforts, to manage these factors, are required to decrease the academic burnout of HCST. Squared multiple correlations, which explain the academic burnout related with the stress from economic pressure and job seeking, test anxiety, learning flow and self factors, were 98.8%. The results are expected to be useful for the development of TOEIC learning curriculum and course to decrease the academic burnout of HCST. In the following study, the analysis about additional factors of influence on academic burnout will be needed.

• The Korean Journal of Applied Statistics
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• v.34 no.6
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• pp.905-922
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• 2021

Cluster analysis is one of unsupervised learning techniques used for discovering clusters when there is no prior knowledge of group membership. K-means, one of the commonly used cluster analysis techniques, may fail when the number of variables becomes large. In such high-dimensional cases, it is common to perform tandem analysis, K-means cluster analysis after reducing the number of variables using dimension reduction methods. However, there is no guarantee that the reduced dimension reveals the cluster structure properly. Principal component analysis may mask the structure of clusters, especially when there are large variances for variables that are not related to cluster structure. To overcome this, techniques that perform dimension reduction and cluster analysis simultaneously have been suggested. This study proposes probabilistic reduced K-means, the transition of reduced K-means (De Soete and Caroll, 1994) into a probabilistic framework. Simulation shows that the proposed method performs better than tandem clustering or clustering without any dimension reduction. When the number of the variables is larger than the number of samples in each cluster, probabilistic reduced K-means show better formation of clusters than non-probabilistic reduced K-means. In the application to a real data set, it revealed similar or better cluster structure compared to other methods.

• Journal of the Korea Academia-Industrial cooperation Society
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• v.18 no.6
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• pp.197-208
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• 2017

The purpose of this study was to construct and test a structural equation model for college student's gambling behavior. A structured questionnaire was completed by 246 college students to analyze the relationships between perspective factors(irrational gambling belief), psychological factors(depression, anxiety), social factors(parental monitoring, parental support, friend support), self-control and gambling behavior. The moderating effects of gender, friends and family's gambling behaviors were examined. The data were analyzed using SPSS 21,0 and AMOS 20.0 programs. Self-control and psychological factors directly affected the college student's gambling behavior, while perspective factors and social factors affected it indirectly. The model fit indices of the modified model were suitable for the recommended levels. The overall study findings suggest the need to develop a gambling prevention program for college students that reinforces self-control, parental monitoring and support, and friend support while reducing irrational gambling belief, depression, and anxiety. An approach that considers gender and a development of a group counseling program for family or friends are also required.

• Journal of the Korea Academia-Industrial cooperation Society
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• v.19 no.3
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• pp.267-277
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• 2018

This study examined the job satisfaction and its association with violence experience, job stress, and burn-out. A total of 1,240 119 rescue workers who worked in 14 fire stations across the country were surveyed. The survey was conducted by self-administered questionnaires from 1 March, to 30 April, 2016. As a result, the score of job satisfaction according to violence experience, job stress, and burn-out were significantly lower in the group with higher scores of violence experience, job stress, and burn-out. Regarding the correlation of job satisfaction with violence experience, job stress, and burn-out, the score of job satisfaction was negatively correlated with the violence experience, job stress, and burn-out. With an analysis of the covariance structure, the job stress was more influential on the job satisfaction than violence experience and burn-out. In addition, a higher violence experience, job stress, and burn-out were found to decrease job satisfaction. On the other hand, a higher the job stress and violence experience resulted in higher burn-out rates. The results suggested that the job satisfaction is influenced more by job stress than by violence experience and burn-out. Therefore, concrete measures will be needed to reduce job stress and promote the job satisfaction of 119 rescue workers.

• Journal of the Korea Academia-Industrial cooperation Society
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• v.15 no.6
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• pp.3685-3695
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• 2014

This study was performed to determine the suicide ideation and its association with hopelessness, psychosocial stress and depression among some middle school students. The survey was administered to 975 middle school students in Gyeongin area during the period, May $1^{st}$ to June $30^{th}$, 2013. Structured self-administered questionnaires were delivered and collected without the respondents' personal information. As a result, concerning the correlation of depression with various factors, the level of suicide ideation was positively correlated with hopelessness, psychosocial stress and depression. Multiple linear regression analysis showed that the factors influencing the suicide ideation included sex distinction, experience of alcohol drinking, hobbies and leisure life, subjective health status, grade, school violence experience, hopelessness, psychosocial stress and depression. An analysis of the covariance structure, hopelessness (BHOP) was more influential on the suicide ideation than psychosocial stress (PWI) and depression (CES-D). The study found that higher hopelessness, severe distress and higher depression tends to increase the suicide ideation.

• Journal of Digital Convergence
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• v.16 no.3
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• pp.345-351
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• 2018

We study convergent influence on job burnout(MBI-GS: Maslach Bunout Inventory-General Survey) and its association with Organizational Commitment Questionnaire(OCQ), Type A Behavior Pattern(TABP) and depression(CES-D: Center for Epidemiologic Studies Depression scale) among Hospital Administrative Staff(HAS). The survey was administered to 201 staff from 9 general hospitals located in J area from Jul. 3rd, 2017 to Jul. 29th, 2017. The structured self-administered questionaries were used. MBI-GS was positively correlated with TABP and CES-D, and it was negatively correlated with OCQ. With the analysis of covariance structure, CES-D was more influential on MBI-GS than OCQ and TABP. The study found the higher TABP and CES-D, and the lower OCQ tend to increase MBI-GS. The results indicate that the efforts, to decrease TABP and CES-D, and to increase OCQ, are required to decrease the MBI-GS of HAS. The results are expected to be useful for organization personnel management to decrease the MBI-GS of HAS. In the following study, the analysis about additional factors of influence on MBI-GS will be needed.

• Journal of the Korea Academia-Industrial cooperation Society
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• v.12 no.10
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• pp.4502-4512
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• 2011

This study was performed to determine the job satisfaction and its association with sociodemographic and health related characteristics, job-related factors, perception on socioeconomic status, professional job perception, job stress and social support among nursing officers. The survey was administered to 542 nursing officers working at military hospitals of the ROK Armed Forces, from Oct. 1 to Nov. 30. The structured self-administered questionnaires were delivered and they were collected without respondents' personal information. As a results, The job satisfaction of respondents turned out to be significantly higher in the following groups: an elder, married, subjective sleep quality is good, feels they are healthy, higher positional status, a longer job career, satisfied with their work, without consider quitting the job, their physical burden of work is adequate. The survey results showed that respondents' job satisfaction is positively correlated with the professional job perception and social support. while it is negatively correlated with job stress. When analyzed by Covariance Structure, it turned out that the professional job perception is more influential on job satisfaction than job stress and social support. The study found the professional job perception, high social support, and low job stress tends to improve job satisfaction. Meanwhile, the study also found that the professional job perception and high social support reduces job stress.