• Nuclear Engineering and Technology
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• v.17 no.4
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• pp.290-301
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• 1985

600MW(e) CANDU Primary Heat Transport System (PHTS) is composed of the two “figure-of-eight” loops and is designed to operate with the 4% Reactor Outlet Header (ROH) quality at its rated power. This existence of the two compressible regions and the positive flow-qualitly-void feedbacks are the sources of the PHTS flow instability. To ensure the PHTS stability, ROH-ROH interconnect pipes are installed as passive systems. This paper describes the investigation of the PHTS flow instability at its design full power condition. Also studied are the interconnect effect and the inherent system damping effect on the system stability. The time domain stability analyses are accessed by using the ATHER/MOD-I code which is the improved version of the KAERI developed ATHER code. Under the most adverse system modelling, the “figure-of-eight” symmetric loop shows divergent flow oscillations. Under with the interconnect, the PHTS stability is remarkably enhanced so that the system becomes stable. However, even under the conservative pressurizer modelling, the PHTS shows the more convergent flow oscillations. With the interconnect and the pressurizer modelling, its stability is highly credited. Conclusively, the inherent system damping by pressurizer itself can credit the PHTS stability without the interconnect.

• Journal of Korea Water Resources Association
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• v.40 no.6 s.179
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• pp.431-446
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• 2007

Groundwater flow in a basin is greatly affected by many hydrogeological and hydrological characteristics of the basin. A groundwater flow model for the Kap-cheon basin ($area=648.3km^2$) in the Geum river basin was established using MODFLOW by fully considering major features obtained from observed data of 438 wells and 24 streams. Furthermore, spatial groundwater recharge distribution was estimated employing accurately calibrated watershed model developed using SWAT, a physically semi-distributed hydrological model. Model calibration using observed groundwater head data at 86 observation wells yielded the deterministic coefficient of 0.99 and the water budget discrepancy of 0.57%, indicating that the model well represented the regional groundwater flow in the Kap-cheon basin. Model simulation results showed that groundwater flow in the basin was strongly influenced by such factors as topological features, aquifer characteristics and streams. The streams in mountainous areas were found to alternate gaining and losing steams, while the streams in the vicinity of the mid-stream and down-stream, especially near the junction of Kap-cheon and Yudeong-cheon, areas were mostly appeared as gaining streams. Analysis of water budget showed that streams in mountainous areas except for the mid-stream and up-stream of Yudeong-cheon were mostly fed by groundwater recharge while the streams in the mid and down-stream areas were supplied from groundwater inflows from adjacent sub-basins. Hence, it was concluded that the interactions between surface water-groundwater in the Kap-cheon basin would be strongly inter-connected with not only streams but also groundwater flow system itself.

• Journal of Digital Convergence
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• v.19 no.5
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• pp.69-79
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• 2021

As the government's public services have been digitized, the necessity of research on the use of e-government services by middle and high-aged people has been raised. Thus, this study aims to verify the mediating effect of digital capacity on the relationship between the family structure and use of e-government services of middle and older aged adults. The study analyzed 1,660 middle and elderly individuals from the 2018 Digital Divide Survey conducted by the National Information Society Agency(NIA) using Baron & Kenny(1986)'s method for mediation. The result is as follows: first, the family structure of the middle and older adults has a significant effect on use of e-government services. Second, the effect of the family structure of middle and older aged people on use of e-government services is partially mediated by digital capacity. The result represents that the elderly living with two or three generations have higher use of e-government services than the elderly living alone and married elderly couple. Also the elderly living with two or three generations have higher digital capacity, resulting in higher use of e-government services. Based on the results, The study suggested that the specific plan for each type of family structure to promote the use of e-government services and a plan to improve the digital capacity of middle and older aged adults.

• Journal of the Korea Academia-Industrial cooperation Society
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• v.20 no.2
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• pp.190-199
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• 2019

This study was conducted to expand the distribution of new technology efficiently by analyzing the structure relationship based on the innovation resistance model and partial least square structural equation model (PLS-SEM). This study selected innovative propensity, relative advantage, compatibility, complexity, trialability, risk, and extension service consisting of educational, technical, and funding services as factors affecting innovation resistance. This study constructed a questionnaire that measured 11 factors including acceptance intention of new technology using 33 indicators. Data was from April to October, 2017, targeting 180 farmers who did not join in projects to spread new technologies of the Rural Development Administration. Results showed the factors positively and significantly affecting innovation resistance include complexity and risk. Innovative propensity did not have any effect on innovation resistance. However, it positively affected acceptance intention of new technology. The service of the extension organizations had a negative effect on innovation resistance, but did not affect acceptance intention of new technology. This study suggests that extension services should promote activities such as education, consulting, publicity and pilot projects related with new technologies in order to minimize the antipathy toward new agricultural technologies.

• Journal of the Korean Association of Geographic Information Studies
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• v.22 no.2
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• pp.133-151
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• 2019

This study aims to analyze cold air characteristics in the watershed areas and to suggest strategies for utilizing them in urban ventilation corridor plans. For this purpose, the Jungnangcheon watershed and Uijeongbu-si in the northern part of Gyeonggi province, and Anyangcheon watershed as well as Yangjaecheon Tancheon watershed and Gwacheon-si in the southern part were selected as study areas. We used KALM (Kaltluftabflussmodell), a cold air simulation model developed in Germany and identified both the cold air flow and the height of cold air layer generated during 6 hours at night. Uijeongbu City is located on the main stream of the Jungnangcheon watershed, and the local cold air from the southern outskirts is an important part of Uijeongbu-si's overall ventilation corridor planning. In addition, the cold air generated in the vicinity of Mt. Sapae flows into the central business district near the city hall and plays a major role in regulating the thermal environment of the city. But, the cold air flows in the eastern part of Uijeongbu-si was not smoothly. The cold air flow generated in the east of Gwanak Mountain and in the west of Cheonggye Mountain was the most active in the northern part of Gwacheon-si. This flow is also a major ventilation corridor in Anyangcheon watershed as well as Yangjaecheon Tancheon watershed. But, the southern part where the cold air flow is not smooth is planed to be developed as 'Gwacheon Knowledge Information Town Public Housing District', so rapid development is expected in the future. Hence, it is suggested that an additional ventilation corridor plan should be established based on the detailed local wind flow analysis.

• Journal of Digital Convergence
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• v.17 no.6
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• pp.297-305
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• 2019

The purpose of this study was to examine resilience and empathy on the relation between humanity and friendship of the early adolescents using structural equation modeling. The subjects were total 332 students of the 5th and 6th grade in elementary school and 1st and 2nd grade in junior school. The data were collected by means of the self-report questionnaire. The results of this study were as follows: Firstly, the direct effect of humanity on resilience, empathy, and friendship was found. Resilience also influence friendship directly, but empathy did not affect friendship. Secondly, humanity had influence on friendship partially mediated by resilience, but not mediated by empathy. This result shows that resilience was better mediated between humanity and friendship than empathy. Additionally, sex differences were found on empathy, but the differences were not found on resilience. The results revealed that the adolescents who scored high on humanity were better at friendship and when the higher humanity score was, the higher level of resilience was found, and this had an indirect effect on friendship quality.

• Journal of Environmental Impact Assessment
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• v.28 no.2
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• pp.141-151
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• 2019

Korea has passed the Act on the Integrated Control of Pollutant-Discharging Facilities in 2015, and the integrated environmental management under the BAT standard is underway. To summarize the nature of integrated environmental management, it is the regulation by the integration of the management of the multi-pollutant source and the technical standard of BATs. In general, in environmental economics, regulation-based on technical standards are known to be inefficient. This paper attempts to evaluate the efficiency of BAT standards from an economic point of view. A simple multi-pollutant model demonstrates that the inefficiency of the environmental tax with imperfect information in a single pollutant situation is amplified under multi-pollutant conditions. The simultaneous introduction of BAT and IPPC can be partially explained by this logic. It is also highlighted by the strengthening of BAT standards by EU, as a countermeasure to the potential deterioration of air quality caused by the change of effective environmental taxes accompanying the fuel and emission price changes.

• The Journal of the Korea Contents Association
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• v.21 no.4
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• pp.815-824
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• 2021

Purpose: This study was to identify the degree of academic stress, college life Adjustment, and social support perceived by nursing students, and to identify the mediating effect of social support between academic stress and college life Adjustment. The participants were 248 nursing college students who have experience in field practice at 4 universities in G metropolitan city. Data analysis was analyzed using SPSS 24.0 as Descriptive statistics, Independent-test, One-way ANOVA, Pearson's correction, and Bootstrapping. Results: The study found 2.68 points for academic stress, 4.11 points for social support, and 3.5 points for college life adjustment. Academic stress was negative correlation with social support and Adjustment to college life, social support was positive correlation with Adjustment to college life. As a result of the analysis by applying the mediating effect verification model 4, first, academic stress had a significant negative effect on social support, second, academic stress had a negative effect on college life adjustment, and social support had a positive effect on college life adjustment. Third, the analysis of the total, direct, and indirect effects of academic stress and social support on college life adjustment showed that they were all significant. In conclusion, it has been found that social support has a partially controlled mediating effect between academic stress and college life adjustment.

• Journal of Korean Library and Information Science Society
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• v.52 no.2
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• pp.235-252
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• 2021

As part of effort to develop the strategies of internationalization of social science academic journals in South Korea, this study attempts to verify the measurement invariance of journal selection criteria across the groups of library and information science researchers and social science researchers. The authors collected 146 survey responses from researchers who have published at least one paper in SSCI/Scopus-indexed social science journals between 2014 and 2016. As a result of the study, it was found that the configural and partial metric invariance of the journal selection criteria held across the two groups, implying that the model of journal selection criteria is appropriate to use in the field of social science as well as library and information science. Additionally, the authors investigated the perceptions of journal selection criteria indicators in the two groups, and it was shown that researchers in both groups considered peer review and indexing in major databases important. The findings of this study could be useful for publishers or academic societies to develop improvement strategies of their journals.

• Journal of Korea Entertainment Industry Association
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• v.14 no.3
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• pp.411-419
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• 2020

With the increasing number of skin care shops, service quality development that can meet the customer needs is needed to obtain differentiated competitive advantage. Accordingly this study was attempted to provide basic data on marketing necessary for operating a skin care shop by identifying the impact of service quality on perceived reciprocity and long-term relationship orientation among the customers using a skin care shop. This study conducted a survey of 290 female customers using skin care shops located in Seoul and Gyeonggi province, Jeollanamdo and Jeollabukdo, and Gyeongsangnamdo and Gyeongsangbukdo through personal visit, e-mail, and post service, and the collected data were analyzed with SPSS Ver. 18.0 and Amos Ver. 18.0. As a result, it was proven that overall goodness-of-fit to the theoretical model of the research hypotheses set in this study is good. In Hypothesis 1, "Skin care specialist's work ability, facility and sanitation, and care products had a significant positive (+) impact on perceived reciprocity," which was partially adopted. In Hypothesis 2, "Skin care specialist's work ability, care products, and devices and tools had a significant positive (+) impact on long-term relationship orientation," which was adopted. In Hypothesis 3, "Perceived reciprocity had a significant positive (+) impact on long-term relationship orientation," which was adopted. Therefore, it can be concluded that skin care specialist's work ability, facility and sanitation, care products, and devices and tools are the service quality elements for allowing customers to feel thankful or encouraging them to visit the skin care shops continuously.