• Journal of Korean Society of Transportation
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• v.20 no.7
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• pp.177-183
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• 2002

Current state-of-the-art of VMS control is based upon simple knowledge-based inference engine with message set and each message's priority. And R&Ds of the VMS control are focused on the accurate detection and estimation of traffic condition of the subject roadways. However VMS display itself cannot achieve a desirable traffic allocation among alternative routes in the network In this context, VMS display strategy is the most crucial part in the VMS control. VMS itself has several limitations in its nature. It is generally known that VMS causes overreaction and concentration problems, which may be more serious in urban network than highway network because diversion should be more easily made in urban network. A feedback control algorithm is proposed in this paper to address the above-mentioned issues. It is generally true that feedback control approach requires low computational effort and is less sensitive to models inaccuracy and disturbance uncertainties. Major features of the proposed algorithm are as follows: Firstly, a regulator is designed to attain system optimal traffic allocation among alternative routes for each VMS in the network. Secondly, strategic messages should be prepared to realize the desirable traffic allocation, that is, output of the above regulator. VMS display strategy module is designed in this context. To evaluate Probable control benefit and to detect logical errors of the Proposed feedback algorithm, a offline simulation test is performed using real network in Daejon, Korea.

• Korean Journal of Social Welfare Studies
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• v.44 no.3
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• pp.237-269
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• 2013

The purposes of the study are to describe the feature of the program components, and to identify their changes in the process of designing the social work programs in the community service agencies in Korea. In order to achieve these purposes, the researchers constructed an analytical framework including 24 program components derived from the related literatures. Data was collected by questionnaires answered by the social workers who were in charge of the program development and implementation. Descriptive statistics analysis and factor analysis were applied to exam the features of the program components in 195 social service programs developed by the funds from the Community Chest of Korea and a private funding foundation. As the result of the analysis, the three noticeable features are found; (1) the agencies have very actively involved in the designing work in the process of developing practice guideline, however they have less involved in the designing work in the process of implementing program; (2) program components which are low level in design activities are intervention models, staff education, and practical ethics; (3) 8 categories of components derived from the theoretical perspective are reduced to 6 categories in the process for developing practice guidelines, finally to 4 categories in the process for implementing the programs. The implications of major findings were discussed in academic and practical perspectives in Korea, including future research works in the area.

• Korean Journal of Social Welfare Studies
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• v.48 no.2
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• pp.203-231
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• 2017

The purpose of this study is to examine the impact of organizational climate on the resource linking skills of social workers working in community welfare centers as well as the mediating effects of reflective thinking in these relationships. To test the mediating effects, we set up a research model based on previous studies on the organizational climate, resource linkage skills, and reflective thinking of social workers. The subjects of this study were social workers in community welfare centers in the Busan metropolitan city. Data were collected using mail surveys, and data from 526 respondents were used for the final analysis. The main results are as follows. First, the organizational climate of community welfare centers has a statistically significant impact on social workers' resource linkage skills. In other words, the more the social workers recognize positively about the organizational climate, the more the utilization of resource linkage skills increases. Second, reflective thinking has a mediating effect in the relationship between the organizational climate and resource linkage skills of social workers in community welfare centers. Based on the study results, practical suggestions for improved resource linkage skills and reflective thinking of social workers in community welfare centers were suggested, and practical implications and future research were discussed.

• The Journal of Korean Academy of Prosthodontics
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• v.57 no.4
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• pp.321-327
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• 2019

Purpose: To evaluate an effect of additional firing process after sintering of monolithic zirconia crown on marginal and internal fit through three-dimensional analysis. Materials and methods: Ten monolithic zirconia crowns were fabricated using titanium abutment model. Monolithic zirconia crowns were designed, milled, and sintered as a control group, and additional firing with coloring was performed as a test group. Three dimensional analysis were performed by using triple-scan protocol, and cross-section analysis on mesio-distal and disto-lingual section was evaluated to measure marginal and internal fitness. Then, three-dimensional surface difference on between two groups was evaluated (${\alpha}=.05$). Results: There was statistically significant difference between the control group ($32.0{\pm}24.3{\mu}m$) and the test group ($17.0{\pm}10.8{\mu}m$) in the mesial axial wall (P < .02) and the control group ($60.2{\pm}24.3{\mu}m$) and the test group ($71.8{\pm}21.5{\mu}m$) in the distal axial wall (P < .01). There was no statistically significant difference at the remaining point. Conclusion: There was no statistical significance on the deviation of inner surface of crown according to firing number, and the results of both group were considered clinically acceptable.

• Nuclear Engineering and Technology
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• v.19 no.2
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• pp.85-98
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• 1987

To analyze the aerosol dynamics in severe accidents of LMFBR, a new computer code entitled MCAD (Multicomponent Aerosol Dynamics) has been developed. The code can treat two component aerosol system using relative collision probability of each particles as sequences of accident scenarios. Coagulation and removal mechanisms incorporating Brownian diffusion and gravitational sedimentation are included in this model. In order to see the effect of particle geometry, the code makes use of the concept of density correction factor and shape factors. The code is verified using the experimental result of NSPP-300 series and compared to other code. At present, it fits the result of experiment well and agrees to the existing code. The input variables included are very uncertain. Hence, it requires uncertainty and sensitivity analysis as a supplement to code development. In this analysis, 14 variables are selected to analyze. The input variables are compounded by experimental design method and Latin hypercube sampling. Their results are applied to Response surface method to see the degree of regression. The stepwise regression method gives an insight to which variables are significant as time elapse and their reasonable ranges. Using Monte Carlo Method to the regression model of LHS, the confidence level of the results of MCAD and their variables is improved.

• Journal of vocational education research
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• v.37 no.2
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• pp.167-190
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• 2018

This study examines based on Cultural-Historical Activity Theory, graduate school student-workers' learning and developmental transfer in school and work. For this purpose, a question is raised. how do components of activities in school and workplace impact on learning and developmental transfer? For this study, based on the results of In-depth interview, questionnaire was designed and quantitative research has been conducted. This study analyzed 288 graduate school student-workers. As a results, First, the components which have an effect on learning were analyzed and the results show that among the components of the school activity system, the competitiveness reinforcement from object, the role of academic major from division of labor, and the interaction with professors from community are significant variables. Second, in case of developmental transfer, the activeness of class participation from tool, the role of academic major from division of labor, and the interaction with professors from community are significant variables of the school activity system and the self realization from object, the role in the workplace from division of labor, the interaction with supervisors from community, and the systemization of work from rule are significant variables of workplace activity system. On the basis of the findings, implications of the study and suggestions for further research are discussed.

• Journal of Climate Change Research
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• v.4 no.3
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• pp.291-303
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• 2013

After establishing national greenhouse gas emission reduction goals, the South Korean government has been pursuing sector- and industry-specific greenhouse gas emission reduction measures; in support of which, metropolitan city / state governing entities, such as Gyeonggi Province, etc., have been in lock steps by establishing and executing climate change measures that are appropriate for the regional characteristics. However, in the case of local governments, difficulties abound due to the fact that the per-unit greenhouse gas emission amounts and the future emission estimates for establishing reduction targets are not clear. In order to establish correct climate change measure policies, the policy directions and the assessment of verified greenhouse gas emission amounts would need to serve as the basis, and along with the national level climate change effect and vulnerability assessment, there's a need to develop methodologies that take into consideration the local characteristics and conditions. To this end, this study calculated the greenhouse gas emission amounts of the City of Siheung, a basic local government in Gyeonggi Province, by using the GEBT (Greenhouse gas Emission Business-as-usual Tool) developed by the National Institute of Environmental Research to facilitate easy calculations of BAU (business-as-usual) emission quantities by local governing entities.

• Journal of Korea Technology Innovation Society
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• v.21 no.3
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• pp.992-1020
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• 2018

The purpose of this study is to investigate the ways to enhance the creativity of R & D teams of government-funded research institutes through systematic empirical studies. For this purpose, a research model was established based on existing research on group creativity and verified through empirical studies. Specifically, This study first attempts to investigate the influence that team diversity, team cohesion, team autonomy and team efficacy have on team creativity. Second, it intends to verify the mediating effects of team efficacy between team characteristics and team creativity. An empirical study was conducted on 102 R & D teams of government-funded research institutes. In the team creativity measurement, the evaluation by the leaders and the self evaluation of the members were performed in parallel. This is to increase the accuracy of the evaluation and to compare the differences of the viewpoints of the two subjects. The result of the analysis demonstrated that team cohesion among the others had a positive influence on team creativity, and that team efficacy possessed certain positive qualities in mediating the relationship between team diversity, team autonomy, and team creativity. Based on these findings, this study discussed its academic implications as well as its practical limitations, and made suggestions on future research tasks that remain.

• Journal of Hospice and Palliative Care
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• v.22 no.1
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• pp.30-38
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• 2019

Purpose: This study analyzed a path through which factors influencing death anxiety in the community-dwelling elderly, assuming personal organismic factors and microsystemic factors based on the ecology model purported by Belsky (1980). Methods: This study was performed with 189 elderly people. Data were collected through a self-report questionnaire. The data were analyzed using the SPSS and AMOS programs. Results: The factors influencing death anxiety in the elderly were depression, family support, social network, and familism value, and the explanatory power of these variables was 22%. Death anxiety increased with higher depression, higher familism value, larger social network, and lower family support. Spiritual well-being and elderly discrimination experience had indirect effects on death anxiety, and these effects were mediated by depression. Conclusion: Depression, family support, social network, and familism value were found to influence death anxiety in the elderly, and the strongest effect came from depression. To reduce death anxiety in the elderly, it is important to improve their relationship with their family and friends. Moreover, support should be provided by establishing local systems, and intervention should be provided to alleviate depression.

• Journal of the Korea Academia-Industrial cooperation Society
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• v.20 no.5
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• pp.352-362
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• 2019

The study investigates one of the long-standing, but still controversial issues in modern finance from the international and domestic perspectives. That is, financial components and differences on corporate profitability are identified and compared under the primary hypotheses. Empirical research settings include the sample data as KOSPI-listed chaebol firms, time reference covering the post-era of the global financial turmoil and two differently defined profitability indices measured by the market- and the book-value bases. A majority of total 7 explanatory variables except firm size and leverage ratio reveal their statistically significant power to explain profitability indices for the chaebol firms in the first hypothesis. The results are generally compatible with those obtained from their counterparts of non-chaebol firms. In the second hypothesis applying multinomial logistic model, the chaebol firms are classified into three groups according to the level of profitability. It is then confirmed that variables to represent the market-valued debt ratio, business risk and growth potential are financially discriminating factors among the three groups. The study may provide a new vision to identify financial factors of corporate profitability for Korean chaebol firms after the global financial crisis, which can enhance the benefits of interested parties at the government or corporate level in a virtuous cycle.