• The Korean Journal of Applied Statistics
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• v.15 no.2
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• pp.233-250
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• 2002

Cox's proportional hazard model is highly-used for the regression analysis of survival data in various fields. Regression diagnostics for the proportional hazards model, however, is not as well-known as the diagnostics for the classical linear models and so these diagnostic methods are not used widely in our practical data analyses. For this reason, we review the residuals proposed by several authors, and investigate how to use them in assessing the model. We also provide the results and interpretation with the analysis of PBC data using S-plus 2000 program.

• Journal of Korean Institute of Industrial Engineers
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• v.40 no.3
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• pp.342-357
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• 2014

The present study analyzes the relationship between research and development (R&D) inputs and performance of a national technology innovation R&D program using successive binary Logistic regression models based on a typical R&D logic model. In particular, this study focuses on to answer the following three main questions; (1) "To what extent, do the R&D inputs have an effect on the performance creation?"; (2) "Is an obvious relationship verified between the immediate predecessor and its successor performance?"; and (3) "Is there a difference in the performance creation between R&D government subsidy recipient types and between R&D collaboration types?" Methodologically, binary Logistic regression models are established successively considering the "Success-Failure" binary data characteristic regarding the performance creation. An empirical analysis is presented analyzing the sample n = 2,178 R&D projects completed. This study's major findings are as follows. First, the R&D inputs have a statistically significant relationship only with the short-term, technical output, "Patent Registration." Second, strong dependencies are identified between the immediate predecessor and its successor performance. Third, the success probability of the performance creation is statistically significantly different between the R&D types aforementioned. Specifically, compared with "Large Company", "Small and Medium-Sized Enterprise (SMS)" shows a greater success probability of "Sales" and "New Employment." Meanwhile, "R&D Collaboration" achieves a larger success probability of "Patent Registration" and "Sales."

• The Korean Journal of Applied Statistics
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• v.17 no.1
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• pp.173-184
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• 2004

A statistical software for nonlinear regression analysis, NLIN2000, is introduced. This software, operated tinder the Window systems, has many user-friendly functions and Provides various statistics. As an upgraded version of the Previous Program operated under the DOS system, NLIN2000 provides easier steps for model specification and fitting process than any other statistical packages. Also it has a database system for model functions which has addition and deletion options. While it can be a useful research tool for statisticians, NLIN2000 can be used practically also by researchers in many other scientific fields, who needs nonlinear regression analysis for their study.

• Journal of KIISE:Software and Applications
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• v.27 no.4
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• pp.370-383
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• 2000

This paper describes a new technique known as specification-based regression testing that is used for the revalidation of concurrent programs after changes are made to specifications. This type of regression testing requires sequencing constraint that specify precedence relations on the synchronization events. In order to extract sequencing constraint automatically, we use Message Sequence Charts(MSCs) that are considered partial and nondeterministic specifications. We show how to identify which sequencing constraint is affected by the modifications made to a specification rather than creating new sequencing constraint from scratch to reduce the cost of regression testing. We also describe how to determine that each affected sequencing constraint is satisfied by a program being tested.

• The Journal of Korean Academic Society of Nursing Education
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• v.20 no.3
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• pp.413-423
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• 2014

Purpose: The purpose of this study was to investigate the relations among emotional intelligence, interpersonal relationship, and job satisfaction among clinical nurses. Methods: Data were collected from 315 nurses who had worked for more than 6 months at five general hospitals by a self-reported questionnaire. The collected data were analyzed with descriptive statistics, t-test, ANOVA, Scheffe-test, Pearson's correlation, and hierarchial regression using SPSS 18.0 program. Results: The mean score of emotional intelligence was 3.42 and the score of self emotional appraisal was the highest. The mean score of interpersonal relationship was 3.44 and the score of intimacy was the highest. The mean score of job satisfaction was 3.04. Emotional intelligence and interpersonal relationship were positively correlated with the job satisfaction. Hierarchial multiple regression analysis showed that use of emotion was the main factor of affecting job satisfaction, which explained 30.8% of the variance for the nurses' job satisfaction together with intimacy, regulation of emotion, position, and monthly salary. Conclusion: These findings indicated that emotional intelligence and interpersonal relationship, especially use and control of emotion and intimacy contributed to nurses' job satisfaction. It is necessary to develop and implement the program for increasing emotional intelligence and interpersonal relationship for improving job satisfaction.

• Korean Journal of Health Education and Promotion
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• v.28 no.2
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• pp.27-40
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• 2011

Objectives: This study was conducted to identify health-promoting behaviors and related factors by type of residence between two groups of college students: those who live in dormitories and those who commute from home. Methods: We used the data from 2,287 students (870 male, 1417 female) from 14 colleges in Daegu and Kyungpook areas and compared health-promoting practice scores, general characteristics, health environment, and parental support. Multiple regression analysis was performed with health-promoting practice scores as a dependent variable. Results: Dormitory residents presented significantly lower health-promoting practice scores than commuters in both gender. Multiple regression analysis showed that the factors associated with health-promoting behaviors were health environment (p<0.05) and parental influence/support (p<0.01) for male dormitory residents. For female dormitory residents interest in health(p<0.05), stress(p<0.05), and parental influence/support(p<0.01) were associated. Conclusions: Systematic development of health education programs would be needed for the practice of health promotion behavior of college dormitory students with the help of environmental and institutional support. We suggest a program for stress management, smoking, health behavior, and alcohol and a parental program to increase contact with their children for a positive parental influence and support.

• Journal of the Korean Society for Precision Engineering
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• v.17 no.2
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• pp.80-88
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• 2000

This paper presents a method to optimize the bump steer characteristics (the change of toe angle with vertical wheel travel) with respect to hard points in the double wishbone front suspension of the four-wheel-drive vehicle using the design of experiment, multibody dynamics simulation, and optimum design program. Front and rear suspensions are modeled as the interconnection of rigid bodies by kinematic joints and force elements using DADS. The design variables with respect to the kinematic characteristics are obtained through the experimental design sensitivity analysis. An object function is defined as the area of absolute differences between the desired and experimental toe angle. By the design of experiment and regression analysis, the regression model function of bump steer characteristics is extracted. The design variables that make the toe angle optimized are selected using the optimum design program DOT. The lane change simulations and tests of the full vehicle models are implemented to evaluate the improvement of vehicle handling performances by the optimization of front bump steer characteristics. The results of the lane change simulations show that the vehicle with optimized bump steer has the weaker understeer tendency than the vehicle with initial bump steer.

• Journal of Korean Public Health Nursing
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• v.28 no.3
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• pp.509-521
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• 2014

Purpose: This study was conducted in order to define factors influencing learned helplessness in undergraduates. Independent variables including external entrapment, internal entrapment, social support, trait anger, state anger, and anger expression were used to predict learned helplessness. Methods: Data were analyzed using the SPSS/WIN 20.0 program for descriptive statistics, Pearson correlation coefficients and stepwise multiple regression. A total of 241 undergraduates recruited from September to November 2012 were included in the study. Results: Four factors of learned helplessness were founded to show significant correlation with external entrapment, internal entrapment, social support, trait anger, state anger and anger expression. Stepwise multiple regression analysis showed that 64% of the variance in learned helplessness was significantly accounted for by internal entrapment, social support and anger expression. Conclusion: This study showed that perceived entrapment and social support are important predictors of learned helplessness. Therefore, in order to reduce learned helplessness in undergraduates, it is necessary to design an intervention program with strategies to help in coping with and reducing perceived entrapments.

• The Journal of Korean Society for School & Community Health Education
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• v.15 no.2
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• pp.51-61
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• 2014

Objectives: This study examined the factors affecting the quality of life relating to oral health using OHIP-14 of college students. Also, this was to help college students to enhance their oral health. Methods: A Total of 334 self-administered questionnaires were collected from university student in Cheon-an. The statistical methods used for data analysis were the descriptive statistics, Independent samples t-test, One-way ANOVA, correlation analysis, multiple linear regression analysis. Results: First, A month pocket money and coffee consumption were significantly related to functional and physical Oral health foctor. Second, A month pocket money and coffee consumption were significantly related to Mental and social Oral health foctor. Finally, multiple linear regression analysis showed that a month pocket money, coffee consumption have a negative effect on the quality of life relating to oral health, Whereas an experience of oral health education a positive effect on this. Conclusion: Oral health related quality of life should be improved by investigating the factors affecting oral health and thus developing the program enhancing the oral health to prevent oral disease. In addition, in order to health promotion physical, mental, social, including the oral health, program development and research incessant must be carried out.

• Journal of East-West Nursing Research
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• v.23 no.2
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• pp.142-149
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• 2017

Purpose: The purpose of this study was to investigate factors affecting trait anger level in undergraduate students. Methods: The participants consisted of 315 undergraduate students at the universities in the P and D cities. Data were collected with a structured questionnaire and analyzed using descriptive analysis, t-test, ANOVA, Pearson correlation coefficients, and multiple stepwise regression with the SPSS/Win 20.0 program. Results: The low trait anger group showed lower levels of anger-out, anger-in and depression compared to the high trait anger group. The anger-control and positive thinking were higher in the low trait anger group than that of high trait anger group. The result of multiple stepwise regression showed that both depression and anger-out were predictors in trait anger in the both groups. In the low trait anger group, anger-control, anger-in, depression, and anger-out were significant factors of trait anger, which accounted for 31% of the total variance. High trait anger level was affected by depression, anger-out and positive thinking, which explained 40% of trait anger. Conclusion: The results of this study suggest that anger management program for undergraduate students should consider trait anger level as well as approaches with customized strategies according to trait anger level.