• Journal of Mechanical Science and Technology
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• v.20 no.4
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• pp.545-553
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• 2006

Generally, the temperature drop under $0^{\circ}C$ on vaporizer surface creates frozen dews. This problem seems to increase as the time progress and humidity rises. In addition, the frozen dews create frost deposition. Consequently, heat transfer on vaporizer decreases because frost deposition causes adiabatic condition. Therefore, it is very important to solve this problem. This paper aims to study of the optimum design of used vaporizer at local LNG station. In this paper, experimental results were compared with numerical results. Geometries of numerical and experimental vaporizers were identical. Studied parameters of vaporizer are angle between two fins $(\Phi)$ and fin thickness $(TH_F)$. Numerical analysis results were presented through the correlations between the ice layer thickness $(TH_{ICE})$ on the vaporizer surface to the temperature distribution of inside vaporizer $(T_{IN})$, fin thickness $(TH_F)$, and angle between two fins $(\Phi)$. Numerical result shows good agreement with experimental outcome. Finally, the correlations for optimum design of vaporizer are proposed on this paper.

• Korean Journal of Environment and Ecology
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• v.6 no.2
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• pp.127-133
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• 1993

To investigate the structure and the conservation strategy of natural forest at Dosolbong area in Mt. Sobaek, 20 plots(400$m^2$) set up with random sampling method. Three groups were classified by cluster analysis. High positive correlations was proved between Acer pseudo-sieboldianum and Tilia amurensis, Weigela subsessilis, Corylus heterophylla var. thunbergii and Stephanandra incisa, Lespedeza bicolor and Styrax obassia, and high negative correlations was proved between Rhododendron schlippenbachii and Symplocos chinensis, Carpinus cordata. Species diversity(H') of investigated area was calculated 2.2521-2.3772. Leontopodium japonicum community at Dosolbong area in Mt. Sobaek should be conserved.

• Journal of Korean Academy of Nursing
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• v.35 no.6
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• pp.1072-1080
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• 2005

Purpose: This paper was conducted to test the reliability and validity of rd-SLS, developed by Podsakoff, et al. (1993) which measured 'substitutes for leadership'. Method: The subjects were 345 nurses in 5 general hospitals. Cronbach's and the Guttman split-half coefficient were used to test the reliability of rd-SLS. Factor analysis, and the correlations of the rv-SLS and SLS with rd-SLS were used for convergent and discriminant validity. Result: Cronbach's data was 0.76 and the Guttman split-half coefficient was 0.52. Twelve factors evolved by factor analysis, which explained $70.4\%$ of the total variance. This result was similar to previous study results. However, 'Indifference toward organizational rewards'-related items were classified two factors. It was not clear t hat the rd-SLS consisted of 13 concepts(factors). The correlations of the rv-SLS and SLS with the rd-SLS were 0.93 and 0.87 respectively. Conclusion: The rd-SLS showed a moderate degree of validity and reliability. Thus, it is recommended to use the rd-SLS in general nursing organizations for screening for leadership substitutes. In addition, it is necessary to clarify the concept of organizational rewards. In a further study, the factor structure of the rd-SLS may be considered.

• Human Ecology Research
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• v.51 no.5
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• pp.527-535
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• 2013

The objective of this study was to investigate whether childcare teachers' job satisfaction plays a mediating role between their intention to change jobs and directors' emotional leadership. The participants of this study were 282 childcare teachers in Seoul. The instruments for this study were Director's Emotional Leadership Scale (2 factors with 18 items), Childcare Teacher's Job Satisfaction Scale (K-CTJSS, 6 factors with 40 items), and Childcare Teacher's Intention to Change Jobs Scale (1 factor with 7 items). These instruments were verified by Cronbach's ${\alpha}$ as a reliability and factor analysis as a validity. The data were analysed by Pearson's productive correlation, stepwise multiple regression and path analysis by the SPSS ver. 20.0 and AMOS ver. 20.0. The results were as follows: First, there were significant negative correlations between directors' emotional leadership and childcare teachers' intention to change jobs, and between childcare teachers' job satisfaction and their intention to change jobs, whereas there were significant positive correlations between directors' emotional leadership and childcare teachers' job satisfaction. Second, the directors' emotional leadership was explained by 22% and the childcare teachers' job satisfaction was explained by 9% of their intention to change jobs. Last, the childcare teachers' job satisfaction mediated between the directors' emotional leadership and childcare teachers' intention to change jobs.

• Journal of the Korean housing association
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• v.16 no.1
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• pp.81-88
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• 2005

To design common facilities that support residents' leisure activities is one of the comtemporary issues in Korea. People became interested in the leisure facilities in near-home environments. This trend encouraged this research study. The objectives of this study are: to analyze the current status and characteristics of leisure facilities in apartment communities, to examine the correlations among leisure facilities, and to suggest design considerations for Korean multi-family housing communities. Subject communities are located in the five metropolitan areas in the United States. The 460 apartment communities were randomly selected after a thorough review of a website for apartment finders. Among them, the 126 communities were selected for the analysis. Primary findings are as follows: (1) A total of 30 facilities were identified as the creational facilities in apartment properties. (2) Some leisure facilities were correlated with the other facilities, based on the Pearson's correlation analysis.(3) In addition to the facilities, some apartment communities provide leisure programs for their residents. These results suggest that architectural interventions and maintenance services as well should be considered in order to lead diverse leisure activities for residents.

• Journal of the Korean housing association
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• v.16 no.6
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• pp.111-120
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• 2005

To design common facilities that support residents' leisure activities is one of the comtemporary issues in Korea. People became interested in the leisure facilities in near-home environments. This trend encouraged this research study. The objectives of this study are: to analyze the current status and characteristics of leisure facilities in apartment communities, to examine the correlations among leisure facilities, and to suggest design considerations for Korean multi-family housing communities. Subject communities are located in the five metropolitan areas in the United States. The 460 apartment communities were randomly selected after a thorough review of a website for apartment finders. Among them, the 126 communities were selected for the analysis. Primary findings are as follows: (1) A total of 30 facilities were identified as the creational facilities in apartment properties. (2) Some leisure facilities were correlated with the other facilities, based on the Pearson's correlation analysis.(3) In addition to the facilities, some apartment communities provide leisure programs for their residents. These results suggest that architectural interventions and maintenance services as well should be considered in order to lead diverse leisure activities for residents.

• Journal of Applied Tourism Food and Beverage Management and Research
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• v.14 no.2
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• pp.39-63
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• 2003

Hotel Enterprises are coping with changing circumstances by utilizing ABM and are downsizing for the sake of Innovation Results by setting up ERP(Enterprise Resource Planning) system. This study is intended to explore the correlations between Activity Based Management(ABM) of Strategic Management and ERP System Satisfaction, and the relations between ERP System Satisfaction and Downsizing. And through this, the methods of effective Strategic Management Development and efficient Downsizing will be suggested The objectives of this study are as follows: (1) to research the definition of Tourist Hotels' ABM (2) to examine the correlations between AMB and ERP system Satisfaction (3) to study the relations between ERP System Satisfaction and Downsizing Study Hypotheses, referring to preceeding study of Doo-jin Kong(2002) and DeLone & McLean, were set up to verify the Study Model. Data Analyses include the questionnaire survey of the Hotels using ERP system, reliability analysis, and regression analysis: for these analyses was used SPSS 10.0, the statistics package program. The conclusions show: First, ABM influences ERP System Satisfaction. Second, ERP System Satisfaction influences Downsizing. Therefore, ABM of Tourist Hotels needs to systematically take advantage of the Information Factors from ERP system and to maximize results by executing Downsizing through System development.

• Journal of Korean Academy of Nursing
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• v.46 no.5
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• pp.744-752
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• 2016

Purpose: This study was done to investigate factors influencing successful aging in middle-aged women. Methods: A convenience sample of 103 middle-aged women was selected from the community. Data were collected using a structured questionnaire and analyzed using descriptive statistics, two-sample t-test, one-way ANOVA, Kruskal Wallis test, Pearson correlations, Spearman correlations and multiple regression analysis with the SPSS/WIN 22.0 program. Results: Results of regression analysis showed that significant factors influencing successful aging were post-traumatic growth and social support. This regression model explained 48% of the variance in successful aging. Conclusion: Findings show that the concept 'post-traumatic growth' is an important factor influencing successful aging in middle-aged women. In addition, social support from friends/co-workers had greater influence on successful aging than social support from family. Thus, we need to consider the positive impact of post-traumatic growth and increase the chances of social participation in a successful aging program for middle-aged women.

• Transactions of the Korean Society of Mechanical Engineers
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• v.15 no.2
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• pp.677-684
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• 1991

A numerical analysis is performed about the effects of aspect ratio on natural convective heat transfer from a vertical isothermal cylinder of 0.deg. C immersed in cold pure water. The results of analysis include velocity profiles, temperature profiles and mean Nusselt number of the steady flow region. As aspect ratio of vertical cylinder increases, the flow and heat transfer characteristics of vertical isothermal cylinder approach to those of vertical isothermal flat plate. Numerical solutions obtained for Rayleigh number and aspect ratio indicate the cylinders can be classified as short cylinder and long cylinder. In the cases of short cylinder and long cylinder, new heat transfer correlations are presented. Here, the coefficient values C of new heat transfer correlations are presented as the function of density extremum parameter $R^*/. Numerical results show that theoretical results are in close agreement with experimental results.ts.

• Transactions of the Korean Society of Mechanical Engineers B
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• v.23 no.8
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• pp.978-986
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• 1999

In this study, the general thermal and flow characteristics of flat tube with micro-channels has been studied and the correlation of Nusselt number and friction factor is proposed. The optimal flat tube geometry is determined by optimal design process. It is assumed to be a three dimensional laminar flow in the analysis of thermal and flow characteristics. The periodic boundary condition is applied since the geometry of flat tube with micro-channels shows uniform cross-section in primary flow direction. Local Nusselt number is examined for thermal characteristics of each membrane, and module average Nusselt number and friction factor are calculated to determine the characteristics of the heat transfer and pressure drop in overall flat tube with microchannels. The correlations between Nusselt number and friction factor are given by Reynolds number, aspect ratio of membranes, and the width of flat tube. ALM (Augmented Lagrangian Multiplier) method is applied to the correlations to determine an optimal shape of flat tube. It is shown that the optimal aspect ratio of flat tube is approximately 1.0, irrespective of the width of flat tube and Reynolds number.