• Journal of Korean Academy of Nursing
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• v.34 no.3
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• pp.515-524
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• 2004

Purpose: The purpose of this study was to develop and test a model to explain the transition state for Korean middle-aged women focusing on the transition concept. Method: A hypothetical model was constructed based on the transition model of Schumacher & Meleis(1994) and tested. Thehypothetical model consisted of 5 latent variables and 11 observed variables. Exogenous variables were demographic characteristics, obstetric characteristics, and health behavior. Endogenous variables were transition state and quality of life with 6 paths. The data from 221 middle-aged women selected by convenience was analyzed using covariance structure analysis. Result: The final model which was modified from the hypotheticalmodel improved to GFI=0.97, AGFI=0.94, NFI=0.94, and NNFI=0.95. The transition state was influenced directly by demographic characteristics, quality of life, and also indirectly by health behaviors. However, the influence of obstetric characteristics was not significant. The transition state was accountable for 68% of the variance by these factors. Conclusion: These results suggest that enhancing health behaviors of the women are necessary to increase quality of life and it consequently contributes toimproving the transition state. This model could be used to explain the health related vulnerability in these ages and to diagnosis individual women.

• Korean Journal of Adult Nursing
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• v.18 no.2
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• pp.213-222
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• 2006

Purpose: This study was designed to construct a structural model for explaining model health-related quality of life in acquired people with physical disabilities. Method: The hypothetical model of this study was consisted of 6 latent variables and 14 observed variables. Exogenous variables included in this model were physical status and economical level. Endogenous variables were social attitudes, family function, self-esteem, and health-related quality of life. Data were collected from 226 acquired people with physical disabilities residing in Seoul and Kyunggi-do from January to February, 2005. The collected data were analyzed using SAS 8.2 version and LISREL 8.32 version program. Results: The results of the fitness test of the modified model were follow as; ${\chi}^2=67.479$ (df=50, p=.05), GFI=.959, AGFI=.914, SRMR=.049, NFI=.961, NNFI=.979, CN=249.244. Health-related quality of life was influenced directly by physical status, economic level, and social attitudes and accounted for 88.8% of the variance by these factors. Conclusion: These results suggest that physical status is the most significant effect on health-related quality of life, and social attitudes and economic level are important factors having influences on health- related quality of life. Therefore improving physical status and economic level, and modifying negative attitudes are necessary to increase health-related quality of life of acquired people with acquired physical disabilities.

• Korean Journal of Adult Nursing
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• v.20 no.4
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• pp.641-651
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• 2008

Purpose: this study was to develop and test the structural model that explains husband and wife compatibility and family health of married middle-aged. A hypothetical model explaining husband and wife compatibility and family health based on literature reviews. There were three theoretical variables and twelve observed variables in hypothetical model. Methods: Data collection was carried out May through July 2005. Data were collected by self-reporting questionnaires from 854 married middle-aged who lived in Seoul, Busan, Daegu, Kyungnam, Kyungpook. Collected data was analyzed using SPSS/WIN 12.0 for descriptive statistics, Pearson Correlation coefficient, and Kolmogorov-Smirnov analysis. Results: LISREL program was used to find the best fit normal which assumes causal relationship among variables. This model was to be good fitting and parsimonious to measure husband and wife compatibility and family health of married middle-aged. Conclusion: Differentiation of self and husband and wife compatibility predicted level of family health. Therefore, a family health improvement program needs to include these two variables.

• Korea Journal of Hospital Management
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• v.6 no.2
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• pp.22-36
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• 2001

The hospital bankruptcy rate is increasing, therefore it is very important to predict the bankruptcy using the existing hospital management information. The hospital bankruptcy is often measured in year intervals, called grouped duration data, not by the continuous time elapsed to the bankruptcy. This study introduces a hierarchical generalized linear model(HGLM) for analysis of hospital bankruptcy data. The hazard function for each hospital may be influenced by unobservable latent variables, and these unknown variables are usually termed as random effects or frailties which explain correlations among repeated measures of the same hospital and describe individual heterogeneities of hospitals. Practically, the data of twenty bankrupt and sixty profitable hospitals were collected for five years, and were fitted to HGLM. The results were compared with those of the logit model. While the logit model resulted only in the effects of explanatory variables on the bankruptcy status at specific period, the HGLM showed variables with significant effects over all observed years. It is concluded that the HGLM with a fixed ratio and a period of total asset turnrounds was justified, and could find significant within and between hospital variations.

• Communications for Statistical Applications and Methods
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• v.24 no.2
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• pp.143-154
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• 2017

A variable selection method based on probabilistic principal component analysis (PCA) using penalized likelihood method is proposed. The proposed method is a two-step variable reduction method. The first step is based on the probabilistic principal component idea to identify principle components. The penalty function is used to identify important variables in each component. We then build a model on the original data space instead of building on the rotated data space through latent variables (principal components) because the proposed method achieves the goal of dimension reduction through identifying important observed variables. Consequently, the proposed method is of more practical use. The proposed estimators perform as the oracle procedure and are root-n consistent with a proper choice of regularization parameters. The proposed method can be successfully applied to high-dimensional PCA problems with a relatively large portion of irrelevant variables included in the data set. It is straightforward to extend our likelihood method in handling problems with missing observations using EM algorithms. Further, it could be effectively applied in cases where some data vectors exhibit one or more missing values at random.

• Journal of the East Asian Society of Dietary Life
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• v.20 no.6
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• pp.987-996
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• 2010

The purpose of this study was to measure customers' perception of the service quality of Korean restaurants and then compare differences in perceived service quality according to customer nationality. Self-administered questionnaires were completed by 2812 subjects, and data were analyzed by frequency, chi-square, t-test, one-way ANOVA, factor, reliability, cluster, and discriminant analysis. Results of the study were as follows. The factor analysis of perceived service quality produced four factors, employee service (5 variables), menu quality (4 variables), price & value (4 variables), and physical environment (4 variables). Cronbach's alpha values for reliability were over 0.8 for all factors. Further, a significant difference was observed in service quality, which was perceived according to customer nationality. A higher mean value of perceived service quality was held by foreigners when compared to Koreans. Especially, the mean value of perceived service quality was significantly low for all items for Japanese compared to foreigners. Cluster analysis divided subjects into two groups based on attitude toward service quality of Korean restaurants: an unfavorable group and favorable group. These two groups differed from each other in general characteristics as well. Limitations and future research directions are also discussed.

• Journal of Korean Society of Industrial and Systems Engineering
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• v.38 no.1
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• pp.143-151
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• 2015

In this paper, we investigate how the power consumption of a heat pump dryer depends on various factors in the drying process by analyzing variables that affect the power consumption. Since there are in general many variables that affect the power consumption, for a feasible analysis, we utilize the principal component analysis to reduce the number of variables (or dimensionality) to two or three. We find that the first component is correlated positively to the entrance temperature of various devices such as compressor, expander, evaporator, and the second, negatively to condenser. We then model the power consumption as a multiple regression with two and/or three transformed variables of the selected principal components. We find that fitted value from the multiple regression explains 80~90% of the observed value of the power consumption. This results can be applied to a more elaborate control of the power consumption in the heat pump dryer.

• Genomics & Informatics
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• v.8 no.3
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• pp.116-121
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• 2010

The association between adiponectin concentration and obesity have been reported and genetic variations of the ADIPOQ gene are known to influence the plasmatic concentration of adiponectin. Therefore, we investigated the effect of AIPOQ single nucleotide polymorphism (SNP) on obesity-related variables, and their modulation by dietary intakes in Korean women. The subjects consisted of 3,217 Korean women aged 40-59 years participating in the Korean Genome Epidemiology Study (KoGES). The general characteristics, anthropometric variables, serum blood profiles were measured. Dietary intake was analyzed using the Food Frequency Questionnaire. Subjects with the T allele of AIPOQ rs182052 showed significantly higher obesity-related variables such as weight (p=0.005), BMI (p<0.000), fat body mass (p=0.005), and waist-hip ratio (p=0.007) than those with the C allele. Moreover, the rs182052 T allele was associated with an increased risk of obesity prevalence (p=0.019). However, there were not any significant interactions observed between the genotype of ADIPOQ rs182052 and dietary intake on BMI and fat body mass. These findings suggest that the obesity-related variables may be more dominantly affected by the genotype of ADIPOQ rs182052 than dietary intake in middle aged Korean women.

• Structural Engineering and Mechanics
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• v.71 no.2
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• pp.165-173
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• 2019

This paper investigates the probability of failure of reinforced concrete beams for limit state of collapse for flexure and shear. The influence of randomness of the variables on the failure probability is also examined. The Indian standard code for plain and reinforced concrete IS456:2000 is used for the design of beams. Probabilistic models are developed for flexure and shear according to IS456:2000. The loads considered acting on the beam are live load and dead load only. Random variables associated with the limit state equation such as grade of concrete, grade of steel, live load and dead load are identified. Probability of failure is evaluated based on the limit state equation using First Order Reliability Method (FORM). Importance of the random variables on the limit state equations are observed and the variables are accordingly reduced. The effect of the reduced parameters is checked on the probability of failure. The results show the role of each parameter on the design of beam. Thus, the Indian standard guidelines for plain and reinforced concrete IS456:2000 is investigated with the probabilistic and risk-based analysis and design for a simple beam. The results obtained are also compared with the literature and accordingly some suggestions are made.

• Korean Journal of Agricultural Science
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• v.49 no.3
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• pp.521-529
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• 2022

This study evaluated the effects of agricultural reflective film and HANSPEK film on the fruit quality attributes and peel color variables of 'Fuji' apples. The reflective films were applied under the tree canopies at 20 and 30 days before harvest (DBH), and a tree with no films was used as the control. Depending on the measurement locations, the light intensity was 7.4 - 14.6% higher in the reflective film treatments than that of the control. However, no difference in the light intensity was observed between the reflective and HASPEK films. In addition, the light intensity was not also different between the 20 and 30 DBH. At harvest, the flesh firmness, fruit weight, soluble solids content, titratable acidity, and internal ethylene concentration were not different regardless of the type of reflective film and treatment time. In addition, the peel color variables were not affected in the equatorial region. However, in the calyx region, the L* and b* values were decreased, and the a* value was increased by the reflective and HANSPEK films compared with the control. Hence, the hue angle was decreased to near 0^o (red), and the peel color was improved. Therefore, this study suggests that the application of the HANSPEK film under a tree canopy could improve the fruit peel color of 'Fuji' apples.