• KSCE Journal of Civil and Environmental Engineering Research
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• v.26 no.5A
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• pp.841-848
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• 2006

There is a complex variation of stress in PSC anchorage zones and box girder diaphragms because of large concentrated load by prestress. According to the AASHTO LFRD design code, three-dimensional effects due to concentrated jacking loads shall be investigated using three-dimensional analysis procedures or may be approximated by considering separate submodels for two or more planes. In this case, the interaction of the submodels should be considered, and the model loads and results should be consistent. However, box girder diaphragms are 3-dimensional disturbed region which requires a fully three-dimensional model, and two-dimensional models are not satisfactory to model the flow of forces in diaphragms. In this study, the strengths of the prestressed box girder diaphragms are predicted using the 3-dimensional grid strut-tie model approach, which were tested to failure in University of Texas. According to the analysis results, the 3-dimensional strut-tie model approach can be possibly applied to the analysis and design of PSC box girder anchorage zones as a reasonable computer-aided approach with satisfied accuracy.

• KSCE Journal of Civil and Environmental Engineering Research
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• v.26 no.4A
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• pp.707-717
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• 2006

As an alternative to conventional prestressed concrete (PSC) girders, various types of PSC girders are either under development or have already been applied in bridge structures. Incrementally prestressed concrete girder is one of these newly developed girders. According to the design concept, these new types of PSC girders have the advantages of requiring less self-weight while having the capability of longer spans. However, the dynamic interaction between bridge superstructures and passing trains is one of the critical issues concerning these railway bridges designed with more flexibility. Therefore, it is very important to evaluate modal parameters of newly designed bridges before doing dynamic analyses. In the present paper, a 25 meters long full scale PSC girder was fabricated as a test specimen and modal testing was carried out to evaluate modal parameters including natural frequencies and modal damping ratios at every prestressing stage. During the modal testing, a digitally controlled vibration exciter as well as an impact hammer is applied, in order to obtain precise frequency response functions and the modal parameters are evaluated varying with construction stages. Prestressed force effects on changes of modal parameters are analyzed at every incremental prestressing stage. With the application of reliable properties from modal experiments, estimation of dynamic performances of PSC girder railway bridges can be obtained from various parametric studies on dynamic behavior under the passage of moving train. Dynamic displacements, impact factor, acceleration of the slab, end rotation of the girder, and other important dynamic performance parameters are checked with various speeds of the train.

• 한국노년학
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• v.31 no.4
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• pp.1135-1153
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• 2011

The study aims to examine the interaction of socio-economic status in education and income in the difference of the level of subjective health, physical health, and mental health of middle-age and the elderly of Korea. While there have been various discussions in precedent study with respect to the serious increase in the number of dependent life alongside with increasing elderly population, research on the health level according to socio-economic status is highly limited, and also how the health level of middle-age and the elderly - whom will arrive at senescence in just a few years - is different. The study aims at analyzing the health level by hierarchy and age based on data targeting the whole nation. As for analysis data, the study utilized 1st Korean Longitudinal Study of Ageing (KLoSA) implemented by Korea Labor Institute, and carried out a path analysis to verify whether income and academic background serve as a parameter to the level of subjective health, physical health, and mental health. As a result, while the subjective health level decreases, the study confirmed an increase in chronic diseases, and extremely low level of mental health when people in middle-age enter the elderly. In addition, the higher the education and income, the more the health levels both on middle-age and the elderly; the result suggests that education background and income have mediated effects in all health level of middle-age and the elderly.

• The Journal of the Korea Contents Association
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• v.22 no.8
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• pp.44-53
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• 2022

The purpose of this study is to plan and develop contents for training social skills using robots for elementary school students. Seven functions (guiding activity, providing reinforcement, guiding students behavior, team setting, presenting team order, timer setting, and checking scores) were developed by analyzing functions that robots can take charge of in the training contents. A total of 8 sessions of social skills training contents were developed by selecting social skills required for academic achievement and social interaction of elementary school students. The lesson consisted of providing positive and negative examples, modeling, role-playing, providing feedback on performance, and encouraging generalization stages using effective strategies for acquiring social skills. After developing social skills training contents using robots for elementary school students, so-called Friendly Friends (FF), a satisfaction survey was conducted on the field application of contents and participating students and teachers to examine the acceptance pattern. As a result, it was found that the participating students and teachers were satisfied with the contents. Finally, the meaning and the expected effects of the 'FF (Friendly Friends)' contents were discussed, and also, the matters to be considered when developing social skills training contents using robots in the future were suggested.

• Korean Journal of Social Welfare Studies
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• v.41 no.2
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• pp.279-308
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• 2010

This study examines the association between family policies and family gap using data for 14 OECD countries. As family policies have different assumptions about women's roles and include variant sub-policies, this study identify two distinct family policies: 'employment support policy' to support women as employed workers and 'caregiving support policy' to support women as caregivers. Meanwhile, women's wage cannot be determined by the effect of 'only' family policy. Therefore, analysis model includes variant macro structure supposed to affect women's labor status and wage, like labor market structure, wage structure(compression), women's social status and economic status, and examines interaction effects between family policies and these labor market and social structures using Fuzzy-Set Qualitative Comparative Analysis (FSQCA). The FSQCA result shows that relatively low family gap is associated with the conjunctual causation of developed 'employment support policy' and compressed wage structure.

• Asia Marketing Journal
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• v.12 no.4
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• pp.113-136
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• 2011

Product harm crises can distort long standing favorable equality perceptions, tarnish a company's reputation, cause major revenue and market-share losses, lead to costly product recalls, and devastate a carefully nurtured brand equity. However, in spite of the devastating impact of product-harm crises, little systematic research exists to asses its marketing consequences. So, this study focuses on the negative publicity about companies and their products. Namely, this study presented how inclusion effect supported the relationship between negative publicity and consumers' response, market performance. According to the results, after negativity publicity was happened, it was appeared that the negativity image spread into other product lines(spillover effect; inclusion effect). Also, when they contact with the negative publicity, respondents negatively evaluated both production evaluation and corporate evaluation. And, in that case of the products with negativity publicity, compared with refutation strategy(defense strategy<study 2>), improving strategy(correction notice) had positive influence on recovery of sales, product evaluation, and corporate evaluation. Finally, as the reaction time toward negativity publicity was faster, the market performance got worse. Especially, according to two-way interaction, when the reaction time was fast, the difference between refutation strategy(defense strategy<study 2>) and improving strategy was not existed in product evaluation and corporate evaluation. However, when the reaction time was late(after a month), improving strategy had more positive evaluation than defense strategy in product evaluation, and corporate evaluation.

• Journal of Wetlands Research
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• v.25 no.4
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• pp.248-256
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• 2023

ESG, which stands for Environmental, Social, and Governance, becomes a keyword in managing a company as it becomes an "indicator" that judge companies. Since the environment has suffered so much damage for economic development, it is now to reflect the enormous environmental costs of the future in the management standard rather than the immediate financial benefits at the expense of the environment. Compared to the days when corporate social responsibility (CSR) was discussed, ESG management has improved significantly as it requires practice beyond the declarative level, but the level of consideration for the environmental field is still not high. There may be many backgrounds, but the biggest problem may be the lack of understanding for other fields. Accordingly, this study aims to inform corporates of the need for investment in the environmental field by explaining ESG reviewed in the environmental field and ESG management required in the environmental field. Furthermore, another purpose is to inform them that ESG management is a win-win strategy that can have a meaningful effect not only in the environmental field where investment is received but also in terms of companies by explaining the benefits that companies can gain through this. To reach this goal, this study proposed a method of restoring a damaged ecosystem based on corporate investment, evaluating its effects based on carbon absorption capacity, and using it as a means of carbon neutrality practice as well as ESG management performance of a company.

• Korean Journal of Agricultural and Forest Meteorology
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• v.25 no.4
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• pp.276-283
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• 2023

Garlic (Allium sativum L.) is one of the most important vegetables used in various foods in Korea and many countries. The growth of garlic is influenced by various abiotic factors such as cultivation temperature, humidity, minimum temperature duration, and photoperiod. This study investigated the effects of increasing temperatures on the plant growth of the northern- ecotype garlic 'Uiseong' in a temperature gradient tunnel. As a result, temperature increase led to decreases in the bulb diameter, weight, and clove pieces of garlic. The rise of cultivation temperature increased the occurrence rate of incomplete bolting in the Northern-ecotype garlic 'Uiseong', resulting in decreases in productivity and a decrease in the yield of marketable garlic, indicating that temperature increases affect the development of garlic bulb formation. The findings of this study are expected to contribute as foundational data for understanding the growth responses of the northern-ecotype 'Uiseong' to increasing cultivation temperatures. The results of this study can be used to develop designing garlic growth models. In addition, the results of this study can improve understanding the interaction between increased temperature and garlic growth.

• Journal of Animal Science and Technology
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• v.65 no.5
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• pp.989-1001
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• 2023

The study evaluated the effects of dietary fiber and energy levels administered during two growing periods (d 0-28 and d 29-56) for pigs exposed to a high temperature. A total of 96 growing pigs were used in six treatments as: Two treatments in thermoneutral temperature (21℃-24℃) with dietary energy of 3,300 and the inclusion of high or low fiber, two treatments in heat stress (30℃-34℃) with dietary energy of 3,300 and the inclusion of high or low fiber, and two treatments in heat stress with dietary energy of 3,450 and the inclusion of high or low fiber. Among standard energy level treatments, heat-stressed pigs showed lower average daily gain (ADG), feed intake, digestibility of dry matter, gross energy, crude protein, and crude fiber in phases 1 and 2. Moreover, higher concentrations of acetate, propionate, butyrate, and total short-chain fatty acid (SCFA) in feces were shown in pigs fed high fiber diets. There was a negative interaction between dietary fiber and energy for the fecal concentration of isobutyrate in phase 1 and valerate in phase 2. Pigs in heat stress treatments showed a higher rectal temperature, respiratory rate, hair cortisol, plasma zonulin, and fecal lipocalin-2. Among heat stress treatments, the overall ADG was increased in pigs fed high fiber. Pigs fed high dietary fiber showed a greater concentration of acetate, propionate, butyrate, and total SCFA. High fiber treatments decreased plasma zonulin. In conclusion, the inclusion of beet pulp, soluble fiber, at the level of 4% looks necessary in pigs diet during heat stress.

• The Journal of the Convergence on Culture Technology
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• v.9 no.5
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• pp.685-695
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• 2023

This study aimed to investigate the current utilization and implications of digital learning support media in the field of French studies, and to explore future research directions. To achieve this, we conducted a comprehensive review of the use of digital media in various learning processes within French studies. Additionally, we examined the direct application of ChatGPT, an emerging technology, to learning by extending its use to foreign language and education fields. Our findings indicate that the application of digital learning support media in French studies is somewhat limited, with selective use in processes such as online class support media, pre-class learning, efficient learning and interaction, and self-directed learning. In the case of ChatGPT, our research found that no studies have been conducted within French studies, and very few studies have been conducted on its practical application in other educational fields. While ChatGPT has a wide range of applications and has shown positive effects on learners, ethical concerns have been raised regarding the quality, source, and reliability of information. Therefore, future research in French studies should focus on educational application and effectiveness verification in university teaching and learning situations, as well as interdisciplinary convergence with digital learning support media.