• Title/Summary/Keyword: DID모형

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Analysis of Service Factors on the Management Performance of Korea Railroad Corporation - Based on the railroad statistical yearbook data - (한국철도공사 경영성과에 미치는 서비스 요인분석 -철도통계연보 데이터를 대상으로-)

  • Koo, Kyoung-Mo;Seo, Jeong-Tek;Kang, Nak-Jung
    • Journal of Korea Port Economic Association
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    • v.37 no.4
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    • pp.127-144
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    • 2021
  • The purpose of this study is to derive service factors based on the "Rail Statistical Yearbook" data of railroad service providers from 1990 to 2019, and to analyze the effect of the service factors on the operating profit ratio(OPR), a representative management performance variable of railroad transport service providers. In particular, it has academic significance in terms of empirical research to evaluate whether the management innovation of the KoRail has changed in line with the purpose of establishing the corporation by dividing the research period into the first period (1990-2003) and the latter (2004-2019). The contents of this study investigated previous studies on the quality of railway passenger transportation service and analyzed the contents of government presentation data related to the management performance evaluation of the KoRail. As an empirical analysis model, a research model was constructed using OPR as a dependent variable and service factor variables of infrastructure, economy, safety, connectivity, and business diversity as explanatory variables based on the operation and management activity information during the analysis period 30 years. On the results of research analysis, OPR is that the infrastructure factor is improved by structural reform or efficiency improvement. And economic factors are the fact that operating profit ratio improves by reducing costs. The safety factor did not reveal the significant explanatory power of the regression coefficient, but the sign of influence was the same as the prediction. Connectivity factor reveals a influence on differences between first period and latter, but OPR impact direction is changed from negative in before to positive in late. This is an evironment in which connectivity is actually realized in later period. On diversity factor, there is no effect of investment share in subsidiaries and government subsidies on OPR.

Evaluating Global Container Ports' Performance Considering the Port Calls' Attractiveness (기항 매력도를 고려한 세계 컨테이너 항만의 성과 평가)

  • Park, Byungin
    • Journal of Korea Port Economic Association
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    • v.38 no.3
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    • pp.105-131
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    • 2022
  • Even after the improvement in 2019, UNCTAD's Liner Shipping Connectivity Index (LSCI), which evaluates the performance of the global container port market, has limited use. In particular, since the liner shipping connectivity index evaluates the performance based only on the distance of the relationship, the performance index combining the port attractiveness of calling would be more efficient. This study used the modified Huff model, the hub-authority algorithm and the eigenvector centrality of social network analysis, and correlation analysis for 2007, 2017, and 2019 data of Ocean-Commerce, Japan. The findings are as follows: Firstly, the port attractiveness of calling and the overall performance of the port did not always match. However, according to the analysis of the attractiveness of a port calling, Busan remained within the top 10. Still, the attractiveness among other Korean ports improved slowly from the low level during the study period. Secondly, Global container ports are generally specialized for long-term specialized inbound and outbound ports by the route and grow while maintaining professionalism throughout the entire period. The Korean ports continue to change roles from analysis period to period. Lastly, the volume of cargo by period and the extended port connectivity index (EPCI) presented in this study showed a correlation from 0.77 to 0.85. Even though the Atlantic data is excluded from the analysis and the ship's operable capacity is used instead of the port throughput volume, it shows a high correlation. The study result would help evaluate and analyze global ports. According to the study, Korean ports need a long-term strategy to improve performance while maintaining professionalism. In order to maintain and develop the port's desirable role, it is necessary to utilize cooperation and partnerships with the complimentary port and attract shipping companies' services calling to the complementary port. Although this study carried out a complex analysis using a lot of data and methodologies for an extended period, it is necessary to conduct a study covering ports around the world, a long-term panel analysis, and a scientific parameter estimation study of the attractiveness analysis.

The Association Between Neurodegenerative Diseases and Development of Type 2 Diabetes (신경퇴행성 질환과 제2형 당뇨병 발생의 연관성)

  • Sang-Woo, Koo;Hojun, Lee;Yang-Tae, Kim;Hee-Cheol, Kim
    • Korean Journal of Psychosomatic Medicine
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    • v.30 no.2
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    • pp.155-164
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    • 2022
  • Objectives : A growing body of evidence links type 2 diabetes (T2D) with a neurodegenerative disease (ND) such as Alzheimer's disease and Parkinson's disease. The purpose of this study is to investigate the relationship between NDs and the development of T2D by comparing the incidence of T2D in a group of various NDs (ND group) and control group. Methods : A population-based 10-year follow-up study was conducted using the Korean National Health Information Database for 2002-2015. We used a retrospective cohort study design to investigate the association of ND with T2D occurrence. The study population included ND (n=8,814) and control (n=37,970) groups, all aged 60 years or over. The Kaplan-Meier method was used to estimate the risk of developing T2D as a function of time. Cox proportional hazards regression models were used to evaluate the relationship between ND and T2D. Results : T2D was developed in a significantly higher percentage of patients in the ND group (53.6%) than in the control group (44.7%). The ND group increased the risk of T2D (HR, 1.43; 95% CI, 1.38-1.47). About one-third of patients in both groups were additionally diagnosed with another ND before the occurrence of T2D during a 10-year follow-up period. When compared to those who did not have another ND during the follow-up period, the incidence of T2D in those who were additionally diagnosed with another ND was higher in both the ND and control groups. Conclusions : The ND group had about 1.4 times higher risk of developing T2D than the control group. Our results showed a positive association between ND and T2D.

Studies on the Procedures of Accelerating Generation Advancement in Wheat and Barley Breeding IV. Advancement of Two Generations of Wheat Materials a Year at Suweon by Growing a Summer Generation (맥류의 세대촉진방법에 관한 연구 IV. 수원지역에서 소맥 1년 2기작 세대촉진재배)

  • Seong, B.Y.;Cho, C.H.;Park, M.W.;Hong, B.H.;Ahn, W.S.;Nam, J.H.
    • KOREAN JOURNAL OF CROP SCIENCE
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    • v.25 no.4
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    • pp.35-42
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    • 1980
  • To establish a generation acceleration technique, two crops a year at field condition of Suweon, 10 varieties different in their spring growth habit were tested with 6 different seeding time after harvesting. These materials were harvested on June 10, 19, 79 and tested for their seed production ability at varions seeding time from July I I to August 15 with a week interval. An immatured seed germination technique and green vernalization methods were applied in cycling generations and the results obtained were summarized as follows. 1. In summer growing, seedlings establishment after transplanting was better in earlier transplanting. 2. Heading time was remarkably enhanced by earlier transplanting. Considering the results of two years early or mid of July was the suitable time to plant the second summer crop. 3. Those varieties of spring growth habit expressed little variations in plant height among the varieties. In 1978 which is referred as warm year produced plant height as tall as 8-16cm and poor crop but produced good crop with 25-65cm plant height in 1979. 4. No definit tendency in the length of spike was. observed among the cultivars but longer spike was found in winter wheat compared to the spring. 5. Number of spikes per plant was ranged from 1 to 3 regardless the transplanting time in 1979. However, more spikes per plant were produced in early or mid of July transplanting and those varieties of higher growth habit than V did not produces any spikes. 6. Higher number of grains per spike was found at earlier transplanted varieties. Therefore, it is concluded that those materials of I-IV growth habit with mid or early July transplanting would be suitable in practical sense considering their ability of seed production. 7. Two-year results indicated that wheat crop can not tolerate the temperature level higher than average 32$^{\circ}C$ C at Suweon. In this regard, the cultivation schedule was established assuming average temperature condition like the year of 1979 which was possible to grow wheats.

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Development and Validation of Change Motivation Scale for Growth and Development (성장 및 발전을 위한 변화동기 척도 개발 및 타당화)

  • Lee Eun Joo;Tak Jin kook
    • The Korean Journal of Coaching Psychology
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    • v.7 no.1
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    • pp.59-89
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    • 2023
  • In this study, change motivation for growth and development is defined as 'the power to set a specific action direction for change based on the perception of one's current behavior in order to achieve a goal that one considers important, and to be willing to act'. In addition, the purpose of this study was to develop and validate a scale to measure the motivation for change for growth and development of general adults. To develop preliminary questions, interviews were conducted with 7 coaching experts and 9 experienced coaches, and an open-ended questionnaire was conducted with 55 adults. Afterwards, 7 factors and 83 questions were selected through three rounds of item classification and content validity verification, and a preliminary survey was conducted targeting 321 general adults, and 42 items, 4 factors, were derived through exploratory factor analysis. did Finally, the main survey was conducted with 631 adults in order to verify the validity of the construct concept of the change motivation scale and the validity of the criterion. Divided into two groups, 315 people in group 1 conducted exploratory factor analysis and 316 people in group 2 conducted confirmatory factor analysis to verify the concept of change motivation scale. As a result of the factor analysis of Group 1, it was found that the 3 factor structure consisting of 31 items was appropriate, and as a result of the confirmatory factor analysis of Group 2, the goodness of fit of the modified model of the 3 factor structure was confirmed, which motivated change. The construct validity of the scale was demonstrated. As a result of analyzing the correlations with various variables for the analysis of convergent validity and criterion-related validity of the Motivation for Change scale, each of the three factors was found to be significantly related to most variables. Finally, the significance, implications and limitations of this study, and future research were discussed.

Evaluation of K-Cabbage Model for Yield Prediction of Chinese Cabbage in Highland Areas (고랭지 배추 생산 예측을 위한 K-배추 모델 평가)

  • Seong Eun Lee;Hyun Hee Han;Kyung Hwan Moon;Dae Hyun Kim;Byung-Hyuk Kim;Sang Gyu Lee;Hee Ju Lee;Suhyun Ryu;Hyerim Lee;Joon Yong Shim;Yong Soon Shin;Mun Il Ahn;Hee Ae Lee
    • Korean Journal of Agricultural and Forest Meteorology
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    • v.25 no.4
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    • pp.398-403
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    • 2023
  • Process-based K-cabbage model is based on physiological processes such as photosynthesis and phenology, making it possible to predict crop growth under different climate conditions that have never been experienced before. Current first-stage process-based models can be used to assess climate impact through yield prediction based on climate change scenarios, but no comparison has been performed between big data obtained from the main production area and model prediction so far. The aim of this study was to find out the direction of model improvement when using the current model for yield prediction. For this purpose, model performance evaluation was conducted based on data collected from farmers growing 'Chungwang' cabbage in Taebaek and Samcheok, the main producing areas of Chinese cabbage in highland region. The farms surveyed in this study had different cultivation methods in terms of planting date and soil water and nutrient management. The results showed that the potential biomass estimated using the K-cabbage model exceeded the observed values in all cases. Although predictions and observations at the time of harvest did not show a complete positive correlation due to limitations caused by the use of fresh weight in the model evaluation process (R2=0.74, RMSE=866.4), when fitting the model based on the values 2 weeks before harvest, the growth suitability index was different for each farm. These results are suggested to be due to differences in soil properties and management practices between farms. Therefore, to predict attainable yields taking into account differences in soil and management practices between farms, it is necessary to integrate dynamic soil nutrient and moisture modules into crop models, rather than using arbitrary growth suitability indices in current K-cabbage model.

Factors influencing stress and depression among Korean and Japanese students: With specific focus on parental social support, resiliency of efficacy and stress management behavior (한국과 일본 대학생의 스트레스와 우울에 대한 분석: 부모의 사회적 지원, 어려움극복 효능감, 스트레스 관리행동의 영향)

  • Youngshin Park ;Akira Tsuda ;Uichol Kim ;Keehye Han ;Euiyeon Kim ;Satoshi Horiuchi
    • Korean Journal of Culture and Social Issue
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    • v.15 no.1
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    • pp.1-28
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    • 2009
  • This study examines factors influencing stress and depression among Korean and Japanese university students and the role that parental social support, resiliency of efficacy and stress management behavior play. Four hypotheses are presented. First, parental social support will have a direct influence on resiliency of efficacy. Second, resiliency of efficacy will have a direct influence on stress management behavior and stress and depression symptoms. Third, resiliency of efficacy will have a mediating influence between parental social support and stress and depression symptoms. Fourth, stress management behavior will have a direct influence on stress and depression symptoms. A total 469 participants, consisting of 289 Korean university students (male=156, female=133) and 180 Japanese university students (male=112, female=68) completed a questionnaire that included Rhode Island Stress Inventory-Short Version (Horiuchi, Tsuda, Tanaka, Yajima & Tsuda, in press), Stress Management Behavior (Evers et al., 2006), CES-D (Radloff, 1977), BDI-II (Beck, Steer & Brown, 1996), Resiliency of Efficacy (Bandura, 1995) and Parental Social Support (Kim & Park, 1999). The results supported the first three hypotheses for both samples. Hypothesis 4 was not supported for the Japanese sample and it was partially supported for the Korean sample. The results indicate that parental social support had a direct and positive influence on resiliency of efficacy. Second, resiliency of efficacy had a direct and positive influence on stress management behavior and stress and depression symptoms. Third, resiliency of efficacy had a mediating influence between parental social support and stress and depression symptoms. Fourth, stress management behavior did not have a direct influence on stress symptoms. Overall, parental social support had a direct positive influence on resiliency of self-efficacy, which in turn had a direct negative influence on stress and depression symptoms.

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Effect of Live Commerce Characteristics on Purchase Intention : Focusing on the Parallel Multiple Mediating Effect of Trust and Flow (라이브 커머스 특성이 구매 의도에 미치는 영향 : 신뢰와 몰입의 이중매개 효과를 중심으로)

  • Kim, Sung-jong;Chung, Byoung-gyu
    • Journal of Venture Innovation
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    • v.5 no.1
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    • pp.59-73
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    • 2022
  • Untact marketing is being activated due to COVID-19. As a result, live commerce, an untact seller, is also active in the e-commerce market. Therefore, in this study, we tried to find out what factors influence consumers when they purchase through live commerce. In particular, since consumers' trust and flow in live commerce platforms and products is important, their mediating effects were analyzed. The research model was established by deriving common variables among the characteristics of live commerce based on previous studies. An online survey was conducted for empirical analysis. 200 users who made at least one purchase in live commerce were analyzed. The study results are as follows. Among the characteristics of live commerce, entertainment, economics, professionality were found to have a positive (+) effect on purchase intention. On the other hand, ease of use did not significantly affect purchase intention. The influence was shown in the order of entertainment, professionality and economics. The mediating effect of trust was found to play a mediating role in that entertainment, economics, and professionality affect purchase intention. On the other hand, a significant mediating effect was not tested between ease of use and purchase intention. As for the mediating effect of flow, it was found that flow plays a mediating role in that entertainment and economics affect purchase intention. On the other hand, the mediating effect of flow in terms of ease of use and economics affecting purchase intention was not tested. As for the multiple mediating effect of flow and trust, the mediating effect of flow was stronger than the mediating effect of trust when entertainment had an effect on purchase intention. In terms of professionality affecting purchase intention, the mediating effect of flow was also stronger than the mediating effect of trust. On the other hand, it was analyzed that only trust had a mediating effect when economics had an effect on purchase intention. The results of this study empirically tested that entertainment, which is a fun and interesting factor of live commerce content, is the most important factor when consumers use live commerce. In addition, various results were derived, such as cases where trust and flow act as mediators at the same time or not at all. Practical implications can be found in that it provided a clue about what to prioritize in order to reach consumers for live commerce platform.

Effects of Social Exclusion on Displaced Aggression: the Mediatingon Effect of Stress and Conditional Direct Effect of Social Support (사회적 배제가 전위된 공격성에 미치는 영향: 스트레스의 매개효과 및 사회적지지의 조건부 직접효과)

  • Yoonjae Noh;Sangyeon Yoon
    • Korean Journal of Culture and Social Issue
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    • v.29 no.4
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    • pp.455-476
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    • 2023
  • This study focused on the characteristics of motiveless crimes that mainly originated from interpersonal problems and were acts of revenge against innocent third parties. This study confirmed the relationship between the experience of social exclusion and displaced aggression and examined the relationship between the two variables. We sought to confirm the role of related factors such as stress and social support. For this purpose, we established and tested hypotheses about the mediatingon effect of stress and the moderated mediatingon effect of social support on the effect of social exclusion experience on displaced aggression among 353 adult males aged between 19 and 49 years. The main results are that, first, social exclusion had a positive effect on displaced aggression. Second, stress was found to partially mediate the relationship between social exclusion and displaced aggression. Third, the hypothesis that social support would moderate the mediating effect of stress was not provedvaild, but the conditional direct effect of social support was confirmed in the mediation model. In other words, social support did not affect the indirect effect mediated by stress, but appeared to moderate the direct effect between social exclusion and displaced aggression. Social exclusion's prediction of displaced aggression was significant only in the average social support group (mean) and the high group (M+1SD), and appeared to increase as the group increased. This means that in groups with high social support, displaced aggression is used as a stress control strategy, which is a different result from previous studies that found that social support plays a role in lowerings aggression. People with low levels of social support showed unexpected results in that they used displaced aggression less frequently despite their experiencinge of social exclusion. In the discussion, the social implications of these results were interpreted, and additional research ideas were proposed to specify the relationship between social exclusion and displaced aggression.

Health and quality of life for Korean people in ageing society (고령화 사회에서 한국인의 건강과 삶의 질)

  • Kyung-Hyun Suh
    • Korean Journal of Culture and Social Issue
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    • v.12 no.5_spc
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    • pp.133-147
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    • 2006
  • Korean society is rapidly becoming an ageing society. The Korean may have to live longer than did their parents. Increasing life expectancy and changing social structure, Korean people are getting interested in quality of life, and well-being is becoming a matter of concern. And, the Korean is fully aware of the importance of health for well-being or good life. This concern about health may bring about specific behaviors related to health. Although health care expenditures of Korea are currently smaller than those of other developed countries, it is continuously increasing. Large portion of increased amount of health care expenditures is to spend for disease prevention and expansion of long-term care facilities. Constructs of well-being of the Korean, not living in western culture, may be different from those of people living in western society. Health is not top-ranked to importance for quality of life in previous studies. It does not mean health isn't determinant factor for good life or well-being. Health is an essential element for well-being. It has been proved in several researches which examined poor quality of life caused by certain diseases and management of health-related quality of life. Some theories relate to health-seeking behaviors suggested the health belief or the attitude toward health, intention to do health behavior, perceived behavioral control, and self efficacy as important factors which could predict health-related behaviors. With getting older, people decline in physical and physiological functions and become vulnerable to chronic diseases. Quality of life depends on how to adjust to these changes in senescence. Social supports, especially supports from offspring, are very important to quality of life in senescence, because supports from offspring have influence on pride of the older, they may be afraid of disclose the conflict with their offspring. Avoiding self-disclosure exclude other source of social supports and harm individual's health, therefore psychological intervention is needed to. Increasing life expectancy of the Korean, Korean government has to provide numerous long-term care facilities as well as psychosocial supports. The Korean, so far, does not recognize that psychologist could render great service to promoting individual or community health and improving individual's quality of life. It is highly expected that psychologists take actively interested and involve in health related to quality of life.