• Korean Journal of Mathematics
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• v.30 no.2
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• pp.205-229
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• 2022

The aim of this paper is to obtain some results which belong to fixed point theory such as strong convergence, rate of convergence, stability, and data dependence by using the new Jungck-type iteration method for a mapping defined in complex-valued Banach spaces. In addition, some of these results are supported by nontrivial numerical examples. Finally, it is shown that the sequence obtained from the new iteration method converges to the solution of the functional integral equation in complex-valued Banach spaces. The results obtained in this paper may be interpreted as a generalization and improvement of the previously known results.

• The Korean Journal of Financial Management
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• v.23 no.1
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• pp.193-225
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• 2006

The purpose of this paper is to analyze contagion in Asian foreign exchange markets using Extreme Value Theory and Copula. Our application deals with asymptotic dependence of daily exchange rate return for a sample of eight countries over period 1997.1.1-2005.4.13. The empirical results are summarized as follows. Firstly, Gumbel Copula is a good model to our data according to the value of AIC. Secondly, the extremal dependence between East Asian crisis countries became lower in the post crisis period than the crisis period. Thirdly, It seemed that high extremal dependence exists between East Asian countries with Singapore. Fourthly, the tail dependence between Indonesia, Malaysia, Thailand, Philippine became higher in the crisis period than the total period and post crisis period. Fifthly, the fact that the extremal dependence between Korea and Indonesia, Malaysia, Thailand, Philippine did not increase during the Asian Financial Crisis showed that the contagion effect was not the reason of the Korea's Fiancial Crisis. Sixthly, the extremal dependence between Asian exchange markets was not very high while comparing with the European exchange markets.

• The Korean Journal of Applied Statistics
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• v.30 no.2
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• pp.215-231
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• 2017

The US presidential primaries take place sequentially in different places with a time lag. However, they have not attracted as much attention in terms of modelling as the US presidential election has. This study applied several autologistic models to find the relation between the outcome of the primary election for a Democrat candidate with socioeconomic attributes in consideration of spatial and temporal dependence. According to the result applied to the 2016 election data at the county level, Hillary Clinton was supported by people in counties with high population rates of old age, Black, female and Hispanic. In addition, spatial dependence was observed, representing that people were likely to support the same candidate who was supported from neighboring counties. Positive auto-correlation was also observed in the time-series of the election outcome. Among several autologistic models of this study, the model specifying the effect of Super Tuesday had the best fit.

• Korean Journal of Human Ecology
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• v.5 no.2
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• pp.131-143
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• 1996

The purpose of this study was to investigate clothing involvement and clothing behavior of women and to indentify the relationship between clothing behavior and clothing involvement. The data were analyzed using percentage, frequency, factor analysis, ANOVA, Scheffe test, t-test, and Multiple Regression. The results of the study were as follows: 1. Five dimensions of clothing involvement were derived by factor analysis such as fashion, interest pleasure, symbolism, and perceived buying risk. 2. There were significant relationships between clothing involvement dimensions and demographic characteristics such as age, educational background and family income level. Those who were younger and not married showed positive relationship among fashion, interest and pleasure of clothing involvement dimensions. Those who had higher educational background showed positive relationship with clothing involvement. Those who were empolyed showed higher clothing involvement with symbolism and perceived buying risk. 3. Age, marital status, and educational background showed important variables as factors that exert influence on clothing behavior: Those who were younger and not married attached importance to interest aesthetics, psychological dependence, and fashion. Those who were older and married attached importance to modesty and comfort. The more educated respondents were more concerned about interest aesthetics, symbolism, psychological dependence, and fashion. 4. The fashion of clothing involvement showed positive relationship in fashion, interest, symbolism, and psychological dependence of clothing behavior, and negative relationship in modesty and comfort. The interest of clothing involvement showed positive relationship in aesthetics and interest, and negative relationship in modesty and comfort of clothing behavior. The pleasure of clothing involvement showed positive relationship in psychological dependence, management, interest, and pleasure of clothing behavior. The symbolism of clothing involvement showed positive relationship in symbolism, modesty, conformity, psychological dependence, and fashion of clothing behavior. The perceived buying risk of clothing involvement showed positive relationship in management, conformity, and comfort and negative relationship in symbolism and fashion of clothing behavior.

• Journal of Korea Society of Industrial Information Systems
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• v.24 no.4
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• pp.37-52
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• 2019

This study examines the effects of supplier dependence on supply chain relationships, communication practices, and relationship performance in manufacturing-part companies. The structural equation modeling technique with AMOS 23.0 was used to test hypotheses using data collected in the research model. The results show that supplier dependence positively affects supply chain relationships and communication practices. In addition, the results confirm the effect of supply chain relationships and communication practices on relationship performance. It is also demonstrated that supply chain relationships and communication practices through supplier dependence play a key role in improving relationship performance for supply chain management. Furthermore, it contributes to the practice of supply chain management as well as to efficiency through collaborative activities of supplier-buyer in the supply chain processes.

• Journal of Korean Public Health Nursing
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• v.34 no.3
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• pp.368-379
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• 2020

Purpose: This study aimed to identify factors influencing nicotine dependence among male college students intending to quit smoking on the basis of the PRECEDE model. Methods: A cross-sectional survey of smokers, enrolled at the Smoking Cessation Support Center in W city in Korea was conducted between September 2015 and December 2016. Data was analyzed using the SPSS program for descriptive statistics, bivariate analyses, and hierarchical multiple regression. Results: The mean score of nicotine dependence was determined to be 2.9. Tobacco craving (β =.34, p<.001), social smoking (β =-.23, p=.004), allowance (β =.22, p=.010) and age of smoking initiation (β =-.20, p=.022) were factors that predicted nicotine dependence of male college students. The final model explained 28.3% of the variation in nicotine dependence (adjusted R2=.28), and was significant (F=7.22, p<.001). Conclusions: We determined that to support smoking cessation, it is necessary to develop anti-smoking programs that consider the social and cultural factors of male college students as well as their personal psychological characteristics.

• Journal of Internet of Things and Convergence
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• v.6 no.4
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• pp.39-48
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• 2020

This study intends to the estimate the determinants and state dependence of long-term care services in Korea. For this purpose, we analyzed the transition patterns among three states of long-term care service utilization over time by using the Korea Welfare Panel Study data with the random effect multinomial logit model. It is found that the result showed a strong state dependence in long-term care service utilization. Especially, long-term care insurance for the elderly showed a strong state dependence among others. Among the individual demographic characteristics, the higher the age, the higher the probability of using long-term care insurance for the elderly, while the lower the probability when married. The characteristics of the residential region showed that the residents of the urban-rural integrated region had a significantly higher probability of using long-term care insurance than the reference region. The results of this study suggest that the long-term care service users have a strong state dependence, which means that it is important to take into account the increase in the utilization period of existing users in future demand forecasting.

• Tuberculosis and Respiratory Diseases
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• v.85 no.4
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• pp.349-357
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• 2022

Background: The most consistently identified mortality determinants for the new coronavirus 2019 (COVID-19) infection are aging, male sex, cardiovascular/respiratory diseases, and cancer. They were determined from heterogeneous cohorts that included patients with different disease severity and previous conditions. The main goal of this study was to determine if activities of daily living (ADL) dependence measured by Barthel's index could be a predictor for COVID-19 mortality. Methods: A prospective cohort study was performed with a consecutive sample of 340 COVID-19 patients representing patients from all over the northern region of Portugal from October 2020 to March 2021. Mortality risk factors were determined after controlling for demographics, ADL dependence, admission time, comorbidities, clinical manifestations, and delay-time for diagnosis. Central tendency measures were used to analyze continuous variables and absolute numbers (proportions) for categorical variables. For univariable analysis, we used t test, chi-square test, or Fisher exact test as appropriate (α=0.05). Multivariable analysis was performed using logistic regression. IBM SPSS version 27 statistical software was used for data analysis. Results: The cohort included 340 patients (55.3% females) with a mean age of 80.6±11.0 years. The mortality rate was 19.7%. Univariate analysis revealed that aging, ADL dependence, pneumonia, and dementia were associated with mortality and that dyslipidemia and obesity were associated with survival. In multivariable analysis, dyslipidemia (odds ratio [OR], 0.35; 95% confidence interval [CI], 0.17-0.71) was independently associated with survival. Age ≥86 years (pooled OR, 2.239; 95% CI, 1.100-4.559), pneumonia (pooled OR, 3.00; 95% CI, 1.362-6.606), and ADL dependence (pooled OR, 6.296; 95% CI, 1.795-22.088) were significantly related to mortality (receiver operating characteristic area under the curve, 82.1%; p<0.001). Conclusion: ADL dependence, aging, and pneumonia are three main predictors for COVID-19 mortality in an elderly population.

• The Journal of the Korea Contents Association
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• v.22 no.5
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• pp.734-745
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• 2022

The purpose of this study is to examine the relationship of parental self-esteem with adolescents' smartphone over-dependence and to investigate whether parental attitudes mediate between them. The SEM was utilized by extracting data from 2,590 pairs of middle school students and their parents in the 1st year from the KCYPS 2018. First, parental self-esteem had a significant correlation with adolescent's smartphone over-dependence. Second, parental attitude mediates the effect of parental self-esteem on adolescent's smartphone overdependence. Third, among six sub-factors of parental attitude, only inconsistency was significant. In conclusion, to prevent teens' smartphone overdependence, parental factors such as parents' self-esteem enhancing and consistent parental attitude to their children is important. Based on these results, practical measures for preventing smartphone over-dependence of adolescents were discussed.

• Journal of Information Technology Applications and Management
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• v.27 no.6
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• pp.153-170
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• 2020

The Educational Restitution Rate is an important parameter that determines the quality of university education. This paper analyzed data from 148 private universities over the 10 years from 2009 to 2018 using data mining techniques in Korea. A significant causal relationship is detected in the fixed effect model as a result of the panel estimation. And the scale of faculty expansion and fund management, which are the university evaluation indicators, and the size of basic funds, respectively, have a positive effect on the ERR, which is within the confidence interval. In the analysis, the more private universities improve the tuition dependence rate, the more decisively positive affecting ERR. As a result of nonparametric regression estimation, when the faculty expansion ratio is reinforced, the effect of economies of scale is detected in some sections, the improvement of the tuition dependence rate, and the result value is generated through the improvement that results are derived at a certain point in time. We hope that the university based on this study can be a basic Indicators for the diagnosis of basic competencies and policy of student-centered education.