• Journal of Korea Port Economic Association
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• v.31 no.1
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• pp.1-14
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• 2015

The standard GARCH model imposing symmetry on the conditional variance, tends to fail in capturing some important features of the data. This paper, hence, introduces the models capturing asymmetric effect. They are the EGARCH model and the GJR model. We provide the systematic comparison of volatility models focusing on the asymmetric effect of news on volatility. Specifically, three diagnostic tests are provided: the sign bias test, the negative size bias test, and the positive size bias test. This paper shows that there is significant evidence of GARCH-type process in the data, as shown by the test for the Ljung-Box Q statistic on the squared residual data. The estimated unconditional density function for squared residual is clearly skewed to the left and markedly leptokurtic when compared with the standard normal distribution. The observation of volatility clustering is also clearly reinforced by the plot of the squared value of residuals of export volume and values. The unconditional variance of both export volumes and export value indicates that large shocks of either sign tend to be followed by large shocks, and small shocks of either sign tend to follow small shocks. The estimated export volume news impact curve for the GARCH also suggests that $h_t$ is overestimated for large negative and positive shocks. The conditional variance equation of the GARCH model for export volumes contains two parameters ${\alpha}$ and ${\beta}$ that are insignificant, indicating that the GARCH model is a poor characterization of the conditional variance of export volumes. The conditional variance equation of the EGARCH model for export value, however, shows a positive sign of parameter ${\delta}$, which is contrary to our expectation, while the GJR model exhibits that parameters ${\alpha}$ and ${\beta}$ are insignificant, and ${\delta}$ is marginally significant. That indicates that the asymmetric volatility models are poor characterization of the conditional variance of export value. It is concluded that the asymmetric EGARCH and GJR model are appropriate in explaining the volatility of export volume, while the symmetric standard GARCH model is good for capturing the volatility.

• Journal of the Korean Regional Science Association
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• v.9 no.2
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• pp.103-119
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• 1993

This research examines the spatial development of rural industrial estates (Nong-gong Jigu) in Chonbuk province and gives insight into the strategies for economic development in the entire region. Selected location factors which are likely to pull new investment into the estates are examined by using questionnaires. Few loction factors except nonlocal factors can be found in explaining why location choices are made. The irrelevance of the analysis based on location factors suggests that an alternative approach should analyze changes in the spatial development of the rural industrial estates. Such an alternative is to understand the dynamics of the spatial organization of production by focusing on characteistics of plant closing in the rural industrial estates. To take into account of the characteristics of plant closing we provide the hypothesized relationships between employment size, organizational structure, inter and intra industrial linkage, characteristics of production processes, and availability of local labor market and the likelihood of closing. A logit model is then made to identify the selected factors which might influence the probability of plant closing. The results from the logit analysis and their implications suggest that the policy should be more concerned with the characteristics of firms, such as size and ownership, as well as of the local labor markets. Given that the Chonbuk region has experienced rapid population decline, together with its poor industrial base, it seems that the success of the policy in the declined rural areas in less certain.

• Korean Journal of Adult Nursing
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• v.26 no.4
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• pp.434-443
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• 2014

Purpose: This study investigated the level of adherence to vestibular rehabilitation exercise program(VREP) and evaluated how health belief model (HBM) variables are related with adherence to VREP in patients with dizziness. Methods: The data were collected from 150 individuals, who agreed to participate in the study between December, 2012 and May, 2013. Adherence to VREP, severity of dizziness, health belief variables (health belief scale) and self-efficacy (self-efficacy scale) were measured. Results: The result of this study showed poor adherence to VREP. The mean adherence score to VREP was $2.11{\pm}1.05$ (1-5). In multivariate analysis, severity of dizziness (p<.001), taking sedative medication (p<.001), high self-efficacy (p<.001), high perceived seriousness (p=.019) & benefit (p=.036) were independent predicting factors explaining 57.7% of adherence to VREP. Conclusion: Adherence to VREP was poor among these patients. To improve the patient's adherence to VREP, strategies to increase perceived seriousness, benefit, or self-efficacy and to decrease barriers are urgently needed.

• Journal of the Korean Operations Research and Management Science Society
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• v.38 no.2
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• pp.117-139
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• 2013

Due to the recent development of SNS(Social Network Service) which is represented by Twitter and Facebook, social commerce market which combines on-line shopping mall and SNS is expanding. With increasing speed of its market, this study is to focus on detecting the crucial variables promoting the use intention, which results in the sustainable competitive advantage in social commerce market. This research empirically analyzed the use intention of social commerce. Also, this study explores the moderating effects of gender in explaining intention to use social commerce. A technology acceptance model is applied for pinpointing the antecedents of intention to use social commerce and for revealing cross-gender differences. The results from a survey of 452 participants reveal that the effects of perceived risk, perceived usefulness, ease for use and subjective norm on intentions to use social commerce differ across gender. Findings imply that the risk-free quality and portrayal of in-group or out-group situations of social commerce need to be communicated to female consumers, along with the social norms of using social commerce. When targeting male consumers, the technological features illustrating the usefulness of social commerce should be focused. This study will provide diverse implications companies providing social commerce services.

• Korean Journal of Adult Nursing
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• v.25 no.4
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• pp.389-399
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• 2013

Purpose: The purpose of the study was to examine the relationships between cognitive coping, hope, depression, and life satisfaction of hemodialysis patients based on the stress-coping model. Methods: For this cross-sectional survey, 142 participants were recruited from 10 local clinics in Seoul and Daegu during 2012-2013. The data collection instruments included the Cognitive Emotion Regulation Questionnaire, the Herth Hope Index, the Hospital Anxiety and Depression Scale, and the Satisfaction with Life Scale. The data were analyzed using descriptive statistics, t-test, ANOVA, Pearson's correlation analysis, and stepwise multiple regression. Results: The cognitive coping scores were significantly related to hope, depression, and life satisfaction. The coping strategies explained 80%, 37%, and 38% of the variances in hope, depression, and life satisfaction, respectively. The most powerful coping strategy was positive refocusing, explaining 73% in hope, 25% in depression, and 25% in life satisfaction. Conclusion: The results of the study indicate that cognitive coping plays an essential role for psychological adaptation of hemodialysis patients. Thus, interventions integrating positive refocusing would help instilling hope of hemodialysis patients in Korea.

• The Korean Journal of Health Service Management
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• v.10 no.3
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• pp.27-37
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• 2016

Objectives : This study was conducted to test the influence of job stress and calling on the organizational commitment of clinical nurses. Methods : 220 clinical nurses at two university hospitals in Busan were recruited. They were asked to complete a questionnaire, and 192 data sets were included in the statistical analysis. Results : The mean score of the clinical nurses' organizational commitment was 4.0. All subdomains of job stress and calling were found to have correlations with organizational commitment. The organizational system (t=-6.099, p<.001), lack of reward (t=-3.990, p<.001), purpose/meaningfulness (t=3.624, p<.001), and occupational climate (t=-3.581, p<.001) were revealed to have influences on the organizational commitment. The model was statistically significant, explaining 52.2% of the variance (F=47.808, p<.001). Conclusions : To help clinical nurses become committed to their organizations, administrators need to build fair and rational organizational systems, strengthen various types of rewards, and help nurses reconcile nursing and the meaning of their lives. In addition, every nurse should endeavor to change the nursing organizational climate which is based on vertical collectivism, to a rational climate.

• KOREAN JOURNAL OF CROP SCIENCE
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• v.60 no.3
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• pp.349-354
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• 2015

The AMMI (additive main effects and multiplicative interaction) and GGE (genotype main effect and genotype by environment interaction) biplot which were accounted for a substantial part of total sum of square in the analysis of variance suggested to be more appropriate models for explaining G $\times$ E interaction. The grain yield of total ten sesame genotypes was significantly affected by environment which explained 61% of total variation, whereas genotype and genotype x environment interaction (G $\times$ E) were explained 16%, 24% respectively. From the results of experiment, three genotypes Miryang49, Koppoom and Ansan were unstable, whereas other three genotypes Kyeongbuk18, Miryang50 and Kanghuk which were shorter projections to AEA ordinate were relatively stable over the environments. Yangbak which was closeness to the mean yield and short projection of the genotype marker lines was regarded as genotype indicating good performance with stability. Ansan, Miryang48 and Yangbaek showed the best performance in the environments of Naju, Suwon, Iksan and Andong. Similarly, genotype Miyrang47 exhibited the best performance in the environments of Chuncheon and Miryang. Andong is the closest to the ideal environment, and therefore, is the most desirable among eight environments.

• Asian Journal of Business Environment
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• v.9 no.2
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• pp.5-15
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• 2019

Purpose - The present study endeavours to investigate the impact of intellectual capital (IC) and its components on corporate sustainable growth in India. In addition, this study aims to find out the most influential component of IC on corporate sustainable growth in India. Research design, data, and methodology - A sample size of top 139 NSE listed non-financial companies over a time period of five years has been used in this monograph. The impact of intellectual capital and its components on corporate sustainable growth has been examined using the longitudinal data analysis technique. Results - The findings of this study bring to light that intellectual capital (IC) as measured by the M-VAIC model demonstrates a significant impact on corporate sustainable growth. Considerably, the results also reveal that almost all the explanatory variables viz. Physical Capital, Relational Capital, Innovation Capital, and Process Capital exercise notable influence in explaining corporate sustainable growth. Moreover, the results demonstrate Innovation Capital (controlling the effect of Physical Capital) represents the most influential component of IC on corporate sustainable growth. Conclusions - The research findings show that in the Indian context, both physical capital, and IC (overall), as well as its components, play a crucial role to explain corporate sustainable growth.

• Journal of Information Management
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• v.33 no.1
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• pp.48-60
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• 2002

According to the rapid increasement of web usage, an appropriate model which supports systematically the web-based application-to-application interactions and the approach which can integrate the new distributed computing platform and the existing environments have been investigated. The web services has emerged as the solution to these needs. This paper describes the background of the emergence of the web services and the definition and characteristics of web services. Then, after explaining the operation mechanism of web services, the core techniques which are essential to implement the web services and the implementation cases are examined. Lastly, the future of web services has been mentioned.

• Journal of the Computational Structural Engineering Institute of Korea
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• v.18 no.1
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• pp.21-28
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• 2005

This study tries to analyzes the torque and engaging time generated in a micro-electromagnetic clutch by using FEM. For the purpose of design change and optimization of the micro-electromagnetic clutch, the torque prediction is very important. We employ a mathematical approach based on the electromagnetic principle. For torque prediction, real material properties are substituted to the constructed axi-symmetric FEM model to obtain the analytical torque and engaging time. The predicted torque and engaging time are compared with those obtained by experiments to discuss the validity of torque and engaging time analysis. The analytical results agrees well with experimental data, therefore explaining the validity of the torque and engaging time prediction method.