• Proceedings of the KWS Conference
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• v.43
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• pp.283-285
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• 2004

In this paper an important class of problems in welding which come under the category of phase change is considered, Solidification and melting are important process in welding field. Phase change problems are accompanied by either absorption or release of thermal energy i,e, heat transfer process. This is complicated by the release or absorption of the latent heat of fusion at the solid-liquid interface. In this study the liberation of latent heat is taken in to account using fixed grid method. The numerical simulation and the finite element codes for the heat transfer analysis including the latent heat term has been developed based on this fixed grid method.

• Human Ecology Research
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• v.60 no.2
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• pp.257-271
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• 2022

The aim of this study was to explore the types of helicopter parenting among college students, and to examine how the identified types of helicopter parenting are associated with intimacy goals in dating. In order to investigate these purposes, 202 college students were recruited and analyzed. With the use of Mplus 7.4, a latent profile analysis identified latent profiles of helicopter parenting. Additionally, multivariate regression analysis was conducted in order to analyze the links between the types of helicopter parenting and intimacy goals in dating by using SPSS 26.0. The main findings of the study were as follows. Firstly, three helicopter parenting classes were identified: 1) strong decision-making, 2) strong helicopter parenting, 3) weak helicopter parenting. Secondly, college students in the strong helicopter parenting class reported significantly higher levels of intimacy goals in dating than those in the strong decision-making class. On the other hand, no significant connection was identified between the type of 'weak helicopter parenting' and the levels of intimacy goals in dating, referencing the type of 'strong helicopter parenting.' These results indicate that helicopter parenting has a certain number of types in nature, and the control-based parental behavior could have an impact on college students' intimacy goals in dating.

• Journal of Korean Academy of Nursing
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• v.49 no.1
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• pp.104-112
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• 2019

Purpose: This study aimed to identify types of quality of life (QoL) based on the 5 dimensions of EQ-5D and predict factors affecting types of QoL. Methods: This study was a secondary analysis using data from the Korean Health Panel Survey-II(2012). Participants were 2,071 middle-aged men who had completed the additional survey in 2012 and the data were analyzed using SPSS 20.0 and Mplus 5.21 for latent analysis. Results: Three latent classes of QoL were identified: serious (2.4% of the sample), threatened (15.5%), and stable types (82.0%). The types and characteristics of QoL among the latent classes differed. On comparing latent type 1 with latent type 2, the socioeconomic status (p<.05), employment status (p<.05), and subjective health status (p<.001) were found to be significant. On comparing latent type 1 with latent type 3, the socioeconomic status (p<.05), current smoking status (p<.001), and subjective health status (p<.001) were found to be significant. On comparing latent type 2 with latent type 3, the socioeconomic status (p<.05), subjective health status (p<.001), stress (p<.001) were found to be significant. Conclusion: The results showed significant heterogeneity in types of QoL and the predictors of QoL by types were different. These findings provide basic information for developing nursing interventions to improve QoL. Specific characteristics depending on the subtypes should be considered during the development of interventions.

• The Journal of The Korea Institute of Intelligent Transport Systems
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• v.21 no.6
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• pp.194-210
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• 2022

The user-centered EV charging infrastructure construction policy the government is aiming for can increase convenience for electric vehicle users and bring new electric vehicle users into the market. This study was conducted to provide an in-depth understanding of the charging behaviors of actual electric vehicle users, which can be used as basic information for the electric vehicle charging infrastructure. Based on charging diary data collected for a week, the charging of electric vehicles was analyzed on a daily and weekly basis, and sequence analysis and latent class analysis were used. As a result, five daily charging profiles and four weekly charging profiles were identified, which are expected to contribute to revitalizing the electric vehicle market by providing key information for decision-making by potential electric vehicle users as well for establishing user-centered charging infrastructure policies in the future.

• 한국노년학
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• v.38 no.4
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• pp.963-979
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• 2018

The purpose of this study was to identify frailty profiles based on physical, psychological, and social domains of functioning and to examine the associated factors showing the differences among frailty profiles. Respondents were 70 years and older(n=403) and latent class analysis was applied to determine the optimal subgroups based on Tilberg Frailty Indicators which comprised of three domains(the physical, psychological, and social domain). Also, we performed multinominal logistic regression analysis to find out factors making differences among frailty profiles. Latent class analysis(LCA) identified three distinct types: multi-frail type(27.0%), psychologically frail type(26.8%), inadequate support type(46.2%). All three types had common difficulties in dealing with daily life problems and did not receive enough help with theses difficulties. Based on the results of the LCA three-class models, people in multi-frail type accumulated problems in physical and psychological domains and had partially social domain. On the other hands, psychologically frail type showed a relatively high anxiety disorder and depression. Lastly, people in inadequate support type reported the lack of helps, but they were relatively healthy. Comparing these groups with inadequate support type, people with multi-frail had lower educational level, poor nutritional management status and were less likely to participate in labor market. People in psychologically frail type were more likely to be male, to live in big cities rather than middle and small cities, and less likely to smoke. Based on these results, our results showed the multifaceted concept of frailty among Korean elderly people and we suggested several implications for preventing frail process.

• Journal of Korean Academy of Nursing
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• v.47 no.6
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• pp.817-827
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• 2017

Purpose: This study aimed to identify latent classes based on major modifiable risk factors for coronary artery disease. Methods: This was a secondary analysis using data from the electronic medical records of 2,022 patients, who were newly diagnosed with coronary artery disease at a university medical center, from January 2010 to December 2015. Data were analyzed using SPSS version 20.0 for descriptive analysis and Mplus version 7.4 for latent class analysis. Results: Four latent classes of risk factors for coronary artery disease were identified in the final model: 'smoking-drinking', 'high-risk for dyslipidemia', 'high-risk for metabolic syndrome', and 'high-risk for diabetes and malnutrition'. The likelihood of these latent classes varied significantly based on socio-demographic characteristics, including age, gender, educational level, and occupation. Conclusion: The results showed significant heterogeneity in the pattern of risk factors for coronary artery disease. These findings provide helpful data to develop intervention strategies for the effective prevention of coronary artery disease. Specific characteristics depending on the subpopulation should be considered during the development of interventions.

• The Journal of Korean Association of Computer Education
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• v.22 no.1
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• pp.31-46
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• 2019

The purpose of this study is to analyze the self-directed learning types of software education learners and to characterize them according to each type. To do this, 429 middle school students participating in online software education at K university were surveyed and a latent class analysis to analyze self-directed learning types was conducted. As a result, the self-directed learning types of the software education learners were classified into 'highest level of self-directed learning type (class 1)', 'self learning style recognition type (class 2)', 'self learning style preference type (class 3)', and 'lack of self-directed learning type(class 4)'. Also, the level of software learning achievement according to self-directed learning type of software education learners was found to be the highest at 'highest level of self-directed learning type (class 1)' and lowest at 'self learning style preference type (class 3)'. Based on these results, we suggested the strategic implications for software education.

• Environmental and Resource Economics Review
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• v.19 no.4
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• pp.853-874
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• 2010

This study examines the acceptability of nuclear facilities using the latent class analysis. Even though, nuclear power is useful in terms of economic and energy security aspects, it is very difficult to expand the existing nuclear power plants or build a new one. Many studies analysed the cause of unacceptability of nuclear facilities but it has not been focused how large portion of people are divided pro and con. It is very important to know the distribution of people by the attitude toward nuclear facilities in order to meet the long term National Energy Plan. Through the latent class analysis with 1,025 respondents, people are classified into three groups(favor-class, support-class, opposition-class). The favor-class is the largest group which has moderate good attitudes toward the nuclear facilities in terms of economy, cleanness. and necessity but concerns a little about safety. The second largest group is the support-class which comprises 1/4 portion of people. The people in the class show the aggressive support for the nuclear facilities. 15% of the respondents belong to the opposition-class which show the negative attitudes to expansion of neclear facilities. In order to increase the acceptability of nuclear faculties, the most urgent work for the government to do is to less people's concern about nuclear safety.

• Korean Journal of Agricultural Science
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• v.45 no.3
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• pp.547-559
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• 2018

Consumers are becoming increasingly interested in what kind of value their food has. Many studies have focused on consumers' preferences and willingness to pay for specific food values. However, few studies have asked consumers to consider or rank the importance of different food values. This paper determined consumers' food values by implementing the best-worst scaling approach and segmented consumers based on the relative importance of general food values that consumers place on them. Among a list of eleven food values (taste, safety, origin, appearance, price, environmental impact, naturalness, convenience, nutrition, fairness, and habit) which was compiled from previous studies on food preferences, on average, safety, nutrition, taste, and price were the most important values to consumers, whereas fairness, habit, appearance, convenience, origin, and environmental impact were the least important values. However, significant variation exists among consumers in terms of the relative importance of food values. To investigate the heterogeneity among consumers, a Latent Class Analysis was performed to classify consumers into subgroups based on responses to questions. Two latent classes were found and characterized as 'safety-nutrition' and 'taste-price'. The 'safety-nutrition' cluster represents 61% of the sample and a group of people who find safety and nutrition centered values to be the most important. Another cluster represents about 39% of the sample, and relative to the first group, this group finds price and taste values to be more important.

• Child Health Nursing Research
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• v.26 no.3
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• pp.385-392
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• 2020

Purpose: The number of Korean adolescents engaging in gambling is increasing, especially among out-of-school adolescents. This study aimed to identify patterns of gambling activities and factors related to specific subgroups of out-of-school adolescent gambling activities. Methods: This descriptive study analyzed secondary data from the 2015 Korea Youth Gambling Problem Survey, including 1,200 out-of-school adolescents. Latent class analysis was conducted to identify patterns of gambling activities. The factors related to gambling subgroups were verified with multinomial logistic regression. Results: Three latent classes of gambling activities were identified: rarely gambling (RG), immediate gain gambling (IGG), and broad gambling (BG). These subgroups differed significantly in terms of gender, age at and type of first gambling experience, number and type of gambling activities, gambling frequency, time and money spent on gambling, problem gambling severity, and motivation for gambling. Compared to the RG subgroup, both the IGG and BG subgroups were strongly associated with an older age at the first gambling experience. Conclusion: Out-of-school adolescents who first gambled at an older age and who gambled mainly in order to gain money immediately were at risk of problem gambling. Developing strategies for early screening and referral to professionals is necessary to prevent gambling problems from worsening.