• Journal of Korean Society of Transportation
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• v.16 no.4
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• pp.195-212
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• 1998

본 연구는 새로운 설계일관성 검토기법의 정립을 위하여 수행되었으며, 이를 위해 속도추정 모형을 개발하였다. 본 연구를 통해 개발된 모형은 차량의 주행속도에 가장 큰 영향을 미치는 주 요소를 고려한 장점을 지니고 있다. 즉 평면곡선에서는 운전자의 시각적 판단을 기초로 등판차량의 주행속도를 추정하였다. 또한 이러한 속도추정이 승용차뿐만 아니라 트럭의 경우로 나누어 이루어짐으로써, 차종별 고려가 가능하도록 하였다. 다음은 본 연구를 통해 이루어진 결과이다. 평면곡선에서는 승용차와 트럭의 속도가 같게 추정되었으며, 시거를 통해 산정된 추정속도는 곡선반경과 밀접한 관계를 갖는다. 종단선형에서 승용차의 속도는 구배의 영향을 받지 않으나, 트럭은 구배의 영향으로 속도가 감소한다. 이 때 트럭에 작용되는 가속도는 모두 세 종류로써, 첫째, crawl speed에 도달할 때까지 작용한 가속도$(a_1)$와 둘째, crawl speed 이후 작용한 가속도$(a_2)$ 그리고 셋째, 하향구배 주행시 작용된 가속도$(a_3)$로 구분된다. Watanatade가 제시한 것과 같이 평지에서 나타나는 평면곡선의 주행속도와 구배지에서의 속도를 단순 비교 함으로써, 작은 속도의 궤적을 따라 평지에서 나타나는 평면곡선의 주행속도와 구배지에서의 속도를 단순 비교함으로써, 작은 속도의 궤적을 따라 합성선형의 속도를 추정하는 것은 합성선형이 차량의 주행속도에 미치는 영향을 간과한 것으로 판단할 수 있다. 그러나 본 모형에서는 합성선형의 영향을 고려하여 승용차와 트럭의 주행속도를 추정함으로써, 보다 현실적으로 주행속도를 추정하였다. 본 연구의 결과는 도로의 설계일관성을 검토하는데 매우 유용한 도구가 될 것이며 향후 운전자의 희망속도 결정, 감속율의 산정, 교통류의 고려, 도로설계의 전산화 자료와 연결 등을 통해 보다 실용적인 결과를 산출할 수 있을 것이다.

• Journal of the Korea Academia-Industrial cooperation Society
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• v.17 no.10
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• pp.509-519
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• 2016

This study intends to examine how the subjective health perception of drinkers influences the depression trajectory change by using longitudinal data for elderly drinkers. This study has set up a balanced panel by combining the results from "Aging study panel research" conducted in the year 2006 (1st), 2008 (2nd), 2010 (3rd), 2012 (4th). A total of 543 elderly drinkers, who have responded to each research have been selected as targets for the final analysis. In the analyses, descriptive statistics and Latent Growth Modeling were conducted to examine the causal relationship between the observed and latent variables. The results are as follows: First, it was found that there was a negative correlation-with statistical significance-between the initial value of subjective health perception and the initial status of depression symptom. Second, there was a positive correlation between the initial value of subjective health perception and the changes of depression symptom. This indicates that elderly drinkers with high health perception usually have high degree of depression change; however, this does not mean it was statistically significant. Third, there was a statistically significant correlation between subjective health perception change and depression symptom change. It was found that the depression change level would be low if the subjective health perception change level was high. Thus, we can assume that the depression symptoms of elderly drinker c would slow down if the subjective health perception level increases.

• Journal of Digital Convergence
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• v.15 no.2
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• pp.67-80
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• 2017

Today, Emotional Intelligence of the leader has become important in order to achieve the achievement of the organization. Especially, the automobile industry is somewhat conservative and the organizational culture of the subcontractor is still much more important than the service industry which has a flexible. In this context, I examine the Emotional Intelligence on Organizational Citizenship Behavior and Innovative Behavior in manufacture of automobile industry focusing on moderating effect of Authentic Leadership. This Study enhances the understanding of Emotional Intelligence and extends the research. Future research will needed to pioneer research methods such as various aspects of measurement and time series of various variables.

• Culinary science and hospitality research
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• v.22 no.3
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• pp.139-154
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• 2016

The purpose of this study is to identify the causality between satisfaction /stress with school life and drinking-related behaviors of students majoring in the Dept. of Culinary Arts. The majors taught in college will connect to the job in the future directly. Therefore, in this regard, the results of this study have great importance for Dept. Culinary Arts student training. Results indicated that a positive perception of drinking partially influenced the levels at < ${\beta}=-.219$, p<0.01> a partial impact on school life satisfaction and stress. Negative perceptions also appeared to influence < ${\beta}=.445$, p<0.01> and < ${\beta}=.213$, p<0.01> levels of satisfaction and stress. Therefore, drinking behavior appears to affect the college life experience stress. Schools will have to incorporate this as part of the curriculum to correct the drinking behavior of students.

• 한국노년학
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• v.29 no.4
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• pp.1611-1628
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• 2009

It is well known that health and psychosocial factors are closely associated with depressive symptoms. Due to limitations in available data and analysis methods, however, little is known about the effects of health and psychosocial factors on depression trajectory. In order to address the limitations, this study examines the predictors of depression trajectory using latent growth curve modeling involving individuals aged 60 and over who participated in the Korean Welfare Panel Study (N=4,919). Controlling for socioeconomic variables, health and psychosocial variables were cross-sectionally associated with depressive symptoms, which is consistent with previous findings. However, the effects of health and psychosocial variables on the rate of depressive symptom change varied. Health variables were significantly associated with the levels of depressive symptoms at wave 1, but these were not significantly associated with the rate of depressive symptoms change. By contrast, although psychosocial variables were significantly associated with depressive symptoms at wave 1, the effects of psychosocial variables on the rate of depressive symptom change varied. Specifically, while self-esteem and family relationship were positively associated with the rate of depressive symptom change, social relationship was negatively associated with the rate of depressive symptom change. Based on the findings, this study discussed implications for intervention and future research.

• Korean Journal of Social Welfare Studies
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• v.40 no.2
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• pp.363-397
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• 2009

The purpose of this study was to find out correlation and predictors of posttraumatic growth of North Korean refugees in South Korea in 7years. This survey was conducted on 105 North Korean refugees in 7 years with questions on socio-demographic characteristics, personal & social variables, psychological trauma in North Korea and stress experience in South Korea. The influence of these variables was analysed. Result indicated that hope for future, perceived satisfaction, and acculturative stress had influence on the total quality of life in the South. And total quality of life affected PTG, especially emotional factors of quality of life during the early 3years living in the South affected PTG.. Additionally not only emotional but also social factors of quality of life also affected PTG with North Korean refugees in the South in 7 years. Finally, social and mental health service programs for North Krean refugees was discussed.

• Korean Journal of Culture and Social Issue
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• v.24 no.1
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• pp.1-27
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• 2018

The purpose of this study was to identify the persistent and dynamic association between bullying and victimization. Gender differences in patterns of school bullying was hypothesized based on the literature. Analysis were based on waves 3-6 of the Korea Children and Youth Panel Survey, a nationally representative data of primary and secondary school students in South Korea (N = 1,881). Autoregressive cross-lagged model was employed to identify the reciprocal association between bullying and victimization in longitudinal data. As hypothesized, regardless of gender, lagged effects were statistically significant between each time points such that current bullying caused future bullying and current victimization led to future victimization. However, there was no cross-lagged effects of current victimization on future bullying nor current perpetration on future victimization for both male and female youth. Findings from this study may have implications for designing policies against school bulling. Not only is short-term intervention for handling immediate psycho-social maladjustment important, but so are long-term plans that prevent youth from falling into continued perpetration and victimization in the system of school bullying.

• 한국노년학
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• v.39 no.1
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• pp.169-188
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• 2019

In this study, the author utilizes longitudinal data of the recent 12 years to verify whether the absolute versus relative income of old age has a significant effect on their life satisfaction of life. The findings of this study show that there is a significant difference in life satisfaction of old age according to respondents' relative income of three reference groups based on their asset quintile and residental area and education. In the correlation analysis using the cross-sectional data, the absolute and relative income level was closely related to the life satisfaction. In the panel regression analysis using the 12 years longitudinal data from the Korea National Labour Panel dataset, the income level of counterparts in those reference groups appeared highly significant in determining the level of life satisfaction of the elderly. However, some demographic variables such as age and marital status did not have a statistically significant effect in the long-term perspective. The income of reference groups in terms of asset levels, education and region as well as their own past life satisfaction level had a significant effect on the elders' life satisfaction determination. These results suggest that the relative income hypothesis in terms of life satisfaction among the elderly is more valid than the previous absolute income hypothesis.

• (The) Korean Journal of Educational Psychology
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• v.32 no.1
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• pp.183-205
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• 2018

This study aims to demonstrate the longitudinal structural relationship between learner-centered instruction, learning motivation, growth beliefs, and academic stress. In particular, this study was carried out to focus on the structural effect of the related variables using data from the 3rd to 5th year of the Gyeonggi Education Panel Study. Results showed that while learner-centered instruction positively predicted both intrinsic and extrinsic motivation of learners, it predicted the former better. In addition, learner-centered instruction influenced academic stress through motivation, both intrinsic and extrinsic motivation were found to increase stress. Further, growth beliefs mediated motivation with learner-centered instruction; specifically, learner-centered instruction influenced learners' positive beliefs about growth, and learners who had growth beliefs had intrinsic motivation. At the same time, external motivation tended to be lower for learners who believed in the possibility of growth. Finally, the perceptions of learner-centered instruction affected academic stress through changes in growth beliefs. However, the other 3 factors (learner-centered instruction, learning motivation, and academic stress) were not statistically significant. In conclusion, learner-centered instruction was able to mitigate academic stress, demonstrating that this relationship is influenced by changes in growth beliefs rather than learning motivation, as previously studied. These results suggest that learners' perceptions and beliefs contribute to not only intrinsic motivation but also academic stress. Furthermore, it is suggested that learners need to change their learning environments in positive ways.

• Korean Journal of Social Welfare
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• v.62 no.2
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• pp.161-185
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• 2010

The purpose of this study is to verify the causal relationship between depression and aggressiveness among adolescents. The 4-year longitudinal data collected from 2,670 4th grade elementary school students by the Korean Youth Panel study was used in this study. From the analysis result using the Autoregressive Cross-Lagged Model, the depression and aggressiveness in adolescents were continued from elementary school 4th grade to middle school 7th grade in significant stability. In addition, the previous aggressiveness turned out to have significant positive effect on the later period depression. Similarly, the previous depression had significant effect on the later aggressiveness, but the direction was negative. This means that the adolescents's depression increases as their aggressiveness increases, but as the depression increases, the later aggressiveness of the adolescents decreases. There were no differences between girls and boys within the relationship of these two variables. Finally, the implication derived from the results, the limitation of this study, and suggestion for following studies were presented.