• KSCE Journal of Civil and Environmental Engineering Research
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• v.28 no.2D
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• pp.163-170
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• 2008

According to the rules, a crash cushion is supposed to set up products that is satisfied with the standard of a performance test after performing the car crash test by road safety facilities and management guide. For development of crash cushion, performance should be estimated through the car crash test eventually. However, there is no reasonable design method which considers passenger's safety and only depend on crash test without an alternative plan. Therefore it incurs a loss materially and takes a lot. Therefore, we are asked to create a systematic design of the crash cushion. This study shows that a scientific basis of applying single degree of freedom when it designs the crash cushion after analyzing vehicle crash test data of crash cushion and also represents design of crash cushion through single degree of freedom response spectrum using calculated by crash test data on crash cushion.

• KSCE Journal of Civil and Environmental Engineering Research
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• v.28 no.5A
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• pp.691-697
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• 2008

Coating the high tension bolted frictional joint has been generally allowed for anti-corrosion purpose. However in case of painting on paying surface of the high tension bolt, the influence on a slip strength of the joint depending on precision of painting has remained controversial. The study thus was intended to identify the slip behavior on high tension bolted frictional joint when applying ceramic painting, which has been currently developed. A slip test was conducted on a high tension bolted frictional joint specimen on which ceramic painting has been applied and a slip load and slip coefficient were measured. Based on result, the safety and usability of ceramic painting-applied high tension bolted frictional joint was evaluated. As a result, a difference to some extent by specimen in terms of load-displacement when a slip occurred was observed but an average slip coefficient appeared to have exceeded 0.4, which is the design frictional coefficient set forth in the specification. To secure the safety and usability of ceramic painting-applied high tension bolted frictional joint, it's necessary to establish the standard for painting as well as to revise the relevant specification.

• KSCE Journal of Civil and Environmental Engineering Research
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• v.26 no.3D
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• pp.499-509
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• 2006

Precast concrete deck has many advantages comparing with the in-situ concrete deck, and has been successfully applied to replacement of the deteriorated decks and to the newly constructed highway bridges in domestic region. In order to apply the precast decks into the railway bridges, however, differences of the load characteristics between the highway and the railway should be properly taken into account including the train load, longitudinal force of the continuous welded rail, acceleration or braking force, temperature change and shrinkage. Proper level of the longitudinal prestress of the tendons that can ensure integrity of the transverse joints in the deck system is of a primary importance. To this aim, the longitudinal tensile stresses induced by the design loads are derived using three-dimensional finite element analyses for the frequently adopted PSC composite girder railway bridge. The effect of the temperature change is also investigated considering the design codes and theoretical equations in an in-depth manner. The estimated proper prestress level to counteract those tensile stresses is above 2.4 MPa, which is similar to the case of the highway bridges.

• 한국노년학
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• v.29 no.4
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• pp.1591-1609
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• 2009

Adult child caregivers and spousal caregivers might deal with differential challenges. Studies about caregivers' psychological outcomes, however, tended to investigate associations between caregiving and its outcomes by pooling adult child caregivers and spousal caregivers together. By using a U. S. sample of family caregivers who assisted a relative with dementia, this study examined whether the relationship of caregivers to care receivers (daughter caregivers or spousal caregivers) made a difference in levels of depressive symptoms. The result showed that wife caregivers were more likely to be depressed than daughter caregivers. For daughter caregivers, role overload, role captivity, and behavior problems significantly influenced on depression. Besides these variables, the level of education was a significant predictor for wife caregivers. Role captivity and behavior problems significantly impacted on depression for husband caregivers. Thus, role captivity and behavioral problems were common predictors for all the caregivers. Specifically, higher levels of role captivity and behavioral problems were likely to make caregivers more depressed. The implication of these results were discussed.

• International Area Studies Review
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• v.15 no.1
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• pp.241-266
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• 2011

This study examines the determinants of proportion of self-employed and their policy implications focusing hotel/restaurant and wholesale/retail sectors in Korea. In this study, we estimate the optimal size of self-employed in Korea using OECD data. Several hypothesis are tested by use of the regression analysis on the panel data of OECD economies during 2000-2007 period. Using the panel data of per capita GNI, unemployment level, income tax burden, we found that the excess supply level of self-employed was about 8.0%~9.5% overall. We also found that the excess supply level of self-employed was 13.7~14.1% for hotel and restaurant sector, and 10.4~11.1% for wholesale and retail sector. This results imply that strategically coordinated programs for noncompetitive sectors are more effectively implemented. Furthermore, more aggressive entry and exit policies are needed to solve the over-supply problem of self-employed in Korea.

• Asia Marketing Journal
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• v.10 no.4
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• pp.35-64
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• 2009

In an effort to increase our understanding of green buying behavior, the present study proposes and tests a comprehensive model of how values influence attitudes toward the environment and preferences for green products in a cross-cultural setting. Data were collected from a survey with consumers in two cultures, diametrically different on values salient to environmental consumerism, the U.S. and Korea. As a result of model testing both at the national and multi-group levels, a refined, final model is presented. While the core human values were found to relate to environmental attitudes and green buying behavior, the patterns of the relationships among the variables emerged to differ between the two cultures, highlighting the importance of cross-cultural investigations in this area. Results suggest that biospheric values significantly influence environmental attitudes and green consumption in both countries. However, the effects of egoism were significant among American respondents whereas altruism appeared to have a significant influence on attitude and behavior in the Korean sample. Findings of this study should aid international marketers in their understanding of what drives consumers' green buying behavior in different cultural settings.

• KDI Journal of Economic Policy
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• v.45 no.4
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• pp.57-77
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• 2023

The Chonsei component holds the highest level of weight (5.4%) in the composition of the Korean consumer price index (CPI). The variations in Chonsei prices are directly reflected in the CPI as a representation of cost swings. The Chonsei refers to a deposit that accumulates the costs related to housing services and is mostly affected by variations in rental rates. Nevertheless, it is important to note that Chonsei prices are also susceptible to fluctuations in interest rates, regardless of the rent prices. Therefore, if Chonsei were directly and one-to-one indexed to the CPI, they could include changes other than residential service prices. After analyzing the time series data of the Chonsei index and rent index inside the CPI, it becomes apparent that the Chonsei index displays an average annual growth rate of 2.3%, whilst the rent index reveals a growth rate of 0.9%. The observed disparity in growth rates indicates a divergence in trends between the two indices. It is posited that the Chonsei index, when capitalized, has had a more rapid increase compared to the rental index, owing to the gradual drop in interest rates. To effectively reflect fluctuations in the housing service costs, proxies for the Chonsei index were utilized in the construction of a consumer price index. The findings of our study suggest that, overall, the newly developed CPI demonstrates a comparatively lower rate of inflation when compared to the official CPI. Furthermore, the inclusion of imputed rents for owner-occupied housing in CPI amplifies this effect.

• Journal of the Korean Society for information Management
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• v.40 no.4
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• pp.403-428
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• 2023

This study investigates the development path and intellectual structure of data literacy research, aiming to identify emerging topics in the field. A comprehensive search for data literacy-related articles on the Web of Science reveals that the field is primarily concentrated in Education & Educational Research and Information Science & Library Science, accounting for nearly 60% of the total. Citation network analysis, employing the PageRank algorithm, identifies key papers with high citation impact across various topics. To accurately trace the development path of data literacy research, an enhanced PageRank main path algorithm is developed, which overcomes the limitations of existing methods confined to the Education & Educational Research field. Keyword bibliographic coupling analysis is employed to unravel the intellectual structure of data literacy research. Utilizing the PNNC algorithm, the detailed structure and clusters of the derived keyword bibliographic coupling network are revealed, including two large clusters, one with two smaller clusters and the other with five smaller clusters. The growth index and mean publishing year of each keyword and cluster are measured to pinpoint emerging topics. The analysis highlights the emergence of critical data literacy for social justice in higher education amidst the ongoing pandemic and the rise of AI chatbots. The enhanced PageRank main path algorithm, developed in this study, demonstrates its effectiveness in identifying parallel research streams developing across different fields.

• The Journal of The Korea Institute of Intelligent Transport Systems
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• v.22 no.5
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• pp.19-29
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• 2023

The accident rate in South Korea is simply classified according to the road type and the number of lanes, but other countries apply various factors affect accidents. In this study, national highways where accidents occurred were divided into urban, rural, older, and modern roads using TAAS(Traffic Accident Analysis System) data, and a model of accident costs savings is suggested. As a result of analyzing 1,416.2 km, the fatality rate(person/100mil-vehicle·km) was 4.21 for urban-older, 1.37 for urban-modern, 2.18 for rural-older, and 0.99 for rural-modern roads. The rates of urban roads had a higher result than rural. The injury rate(person/100mil-vehicle·km) for urban-older was 182.63, that for urban-modern was 103.42, that for rural-older was 67.44, and that for rural-modern road was 42.96, which showed a similar pattern to fatality rates. Accident rates of a modern road were much lower than the KDI Guideline. The benefit of applying the result of this study was calculated and the valuation of accident costs savings is increased from 0.6% to 14.1%, while B/C is improved from 0.626 to 0.724.

• Industry Promotion Research
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• v.8 no.4
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• pp.123-129
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• 2023

This study was intended to discuss the economic exclusion of the elderly, which may be experienced in a super-aged society, and to propose a method to improve the interpersonal satisfaction of the elderly through the expansion of social networks in order to overcome this. As a result of this study, first, it suggests that the method of overcoming economic exclusion and improving human satisfaction requires a high interest in women in the subject, and the elderly, low-educated, It was found that it is urgent to overcome the economic exclusion of the low-income class. Second, as a result of examining the effect of social network on human relationship satisfaction, it was found that the more women, the higher the age, the more shopping, and the smoother communication with children, the higher the human relationship satisfaction. Third, as a result of examining the effect of economic exclusion on human relationship satisfaction, it was found that the more leisure activities visited relatives and relatives, and the more paid facilities used social networks, the lower the relationship satisfaction. Therefore, it can be seen that improvement measures for leisure activities and social networks are required. Fourth, as a result of examining the mediating effect of the social network, the social exclusion in the causal relationship in which the independent variable economic exclusion affects the dependent variable, human relationship satisfaction, The relational network was found to have a complete mediating effect. In conclusion, economic exclusion and social network affect human relationship satisfaction, and it was found that human relationship satisfaction improved only when economic exclusion was overcome and social network was improved.