• The Magazine of the Society of Air-Conditioning and Refrigerating Engineers of Korea
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• v.31 no.7
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• pp.53-64
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• 2002

$CO_2$ 20세기 초 천연 냉매 $CO_2$는 광범위하게 사용되었지만 프레온계 냉매의 출현으로 1940년경부터 $CO_2$냉매는 사용이 제한되었다. 그러나 반 세기 동안 사라졌던 $CO_2$냉매는 1980년 후반에 노르웨이 과학 기술대학 (NTNU)과 북구 최대 민간연구소 (SINTEF)의 Lorentzen 교수에 의해 $CO_2$천연 냉매 사용을 재고하게 되었다. 프레온계 냉매의 환경적 논쟁이 쟁점이 되면서 천연 냉매 사용을 재고하게 되었다. 특히 비가연성과 비유독성으로 인한 $CO_2$냉매가 주목을 받고 있다. 초월임계 사이클레서의 고압 제어에 대한 새로운 개념은 Lorentzen 교수와 동료 연구원에 의해서 특허로 제안되었다. 이에 대한 상업적 권리를 Norsk Hydro사는 1990년에 얻었고,1990년대 초반에 NTNU/SINTEF의 공동 연구개발 프로그램을 통해 기술 경쟁력과 실현 가능성이 검증되었다. 현재 연구소에서는 최초로 초월임계 $CO_2$사이클을 이용한 상업용 온수 열펌프 시스템, 2003년 시작할 연료전지 전기 자동차에 대한 연구를 수행하고 있다. NTNU/SINTEF에서 개발된 $CO_2$기술은 Hydro-SINTEF 공동 벤처 기업인 Shecco기술회사를 통해 제조업자에게 허가된다. 본 고에서는 NTNU/SINTEF에서 수행하였거나 수 중인 과제들을 중심으로 유럽의 $CO_2$시스템의 결과와 주요 개발 범위를 정리하였으며, 특히 작동유체로서의 $CO_2$냉매의 특징을 간단히 설명하고, 온 수 열 펌프, 자동차용 공조기 및 열 펌프, 상업 냉동기 등이 기술되었다. 그 외 압축기 위주의 요소기술 개발에 관한 내용도 기술되었고, 차세대 기술 경향과 전망에 대해서도 제시되었다. 제시되었다.성균 350$\times$$10^4$ CFU균, 방선균 434$\times$$10^4$ CFU균, 진균 676$\times$$10^4$ CFU균으로 진균의 개체수가 비교적 높게 나타났으며, 비산불지역에서는 호기성균 328$\times$$10^4$ CFU균, 방선균 319$\times$$10^4$ CFU균, 진균 461$\times$$10^4$ CFU균으로 진균의 개체수가 높게 나타났다. 토양미생물은 호기성균, 방선균, 진균 모두 비산불지역 보다 산불지역에서 많이 나타났다. 본 조사지역에서 호기성균은 활엽수림보다 침엽수림에서 많게 나타났으며, 방선균과 진균은 침엽수림보다 활엽수림에서 많이 나타났다.효과와 이를 이용한 자기냉동의 방법 그리고 최근에 이루어진 새로운 진전에 대해 소개하고 공기조화 및 냉동분야에의 적용 가능성을 전망해 보고자 한다.및 도입 등 선주들에게 다양한 선박건조자금을 제공하여 내수기반 확충에도 노력해야 할 것 이다.있었다., 인삼이 성장될 때 부분적인 영양상태의 불충분이나 기후 등에 따른 영향을 받을 수 있기 때문에 앞으로 이에 대한 많은 연구가 이루어져야할 것으로 판단된다.태에도 불구하고 [-wh]의미의 겹의문사는 병렬적 관계의 합성어가 아니라 내부구조를 지니지 않은 단순한 단어(minimal $X^{0}$ elements)로 가정한다. 즉, [+wh] 의미의 겹의문사는 동일한 구성요 소를 지닌 병렬적 합성어([$[W1]_{XO-}$ $[W1]_{XO}$ ]$_{XO}$)로 그리고 [-wh] 의미의 겹의문사는 중복된 발은을 지닌 한 단어로 ([W]$_{XO}$ )

• Journal of Service Research and Studies
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• v.12 no.3
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• pp.45-59
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• 2022

This study attempted to investigate how the transformational leadership perceived by flowers of telemarketing organizations. In particular, this study explored the moderating effect of followership in the relationship between transformational leadership and organizational performance. To verify the research model, 321 surveys collected from 10 domestic call centers were analyzed. Reliability, correlation, factor analysis, and hierarchical regression analysis were performed, and as a result of the analysis, it was found that the transformational leadership in the telemarketing organizations had a positive effect on organizational performance. In addition, it was confirmed that goal consistency, proactive participation, critical thinking, and team spirit, which are the four sub-variables of followership, all have a positive (+) effect on organizational performance, and both goal consistency and proactive participation moderate the relationship between transformational leadership and organizational performance. Considering the special working environment of telemarketing organizations, the results of this study suggest the need for a corporate educational role to increase transformational leadership and followership and the need to build environments by setting up an atmosphere for members to exercise follow-up, and opening up communication structures for members to follow.

• Korea Trade Review
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• v.43 no.6
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• pp.161-192
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• 2018

The hotel industry in China has shown great growth both in terms of quantity and quality, but management of the most important element of the success of the hotel company is still not enough. The purpose of this study is to investigate the effects of emotional intelligence including self emotional appraisal, others' emotional appraisal, regulation of emotion, use of emotion on Chinese hotel employees' resilience to improve job satisfaction, organizational commitment, and to reduce turnover intention. Also, the relationship between job satisfaction, organizational commitment, and turnover intention was investigated. In order to analyze this, we surveyed 322 employees of Shanghai 4, 5star hotel in China. Empirical analysis showed that self emotional appraisal, regulation of emotion, and use of emotion of Chinese hotel employees had a positive effect on resilience, but others' emotional appraisal did not affect resilience. In addition, the resilience showed a positive effect on job satisfaction and organizational commitment, but not on turnover intention. Also, job satisfaction has a significant negative effect on organizational commitment and turnover intention, and organizational commitment has a significant negative impact on turnover intention. This study aims to provide a better understanding of emotional intelligence and resilience, and to provide effective management of human resources management.

• Progress in Superconductivity and Cryogenics
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• v.25 no.2
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• pp.10-13
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• 2023

High-T_C superconductivity (HTSC) has been the central issue in the field of condensed matter physics for decades. An essential part of the research on superconductivity is finding new exotic superconductors. It was recently suggested that Ir-substituted La_0.7Sr_0.3MnO₃ (LSMIO) is a new high-T_C superconductor. However, systematic studies to experimentally verify the superconductivity have not been done. Here, we report the growth processes of LSMIO thin films and their electrical transport properties. We observed a clear negative correlation between the intensity of the laser utilized for film deposition and the Curie temperature of the deposited film. We attributed this effect to the suppression of Sr concentration in the LSMIO films as the laser intensity increased. However, our LSMIO films show conventional ferromagnetism instead of HTSC. To realize the HTSC in LSMIO systems, further exploration of diverse compositions of LSMIO compounds is essential.

• Journal of Ethics
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• no.97
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• pp.279-306
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• 2014

This study presents the leadership model that is to build of ethical and cultural leadership. This model is to operat the functions of a systemof leadership that based on the universal principles of life, that is performed bybalance and harmonized judgment of the ideal ethical oughtfulness and cultural values, and practise ethically through relationship, process, and skill of leadership. And this model turn out to lead a real impact and then overcome conflict, problem solving, motivation. To check the validity of leadership, this study analysis the case study of leadership of King Sejong. His leadership is based at heaven that on the basis of the universal principles of life. The ideal ethical oughtfulness is to cares for people and the value of the cultural is to cherish the people's will. His leadership is to be balance and harmonized judgment of the ideal ethical oughtfulness and the cultural values by practice of virtues through relationship, process, and skill of leadership. Leadership relationship is a equal role relationship that are the children of the sky, thus to be coexistence and harmonyin close collaboration. Leadership process is a process of transvaluation to ensure the validity of the values by rational discussion and persuasion. Leadership skills led to active obedience through leading by example and love of learning. King Sejong' leadership is the leadership that ethical and cultural leadership become well-implemented.

• Korean Journal of Social Welfare Studies
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• v.41 no.1
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• pp.175-201
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• 2010

The purpose of this study was to examine the mechanism through which youth school-based mentoring program impacts mentees' psychological and school-related outcomes such as self-esteem, self-efficacy, and attitudes toward school. The hypothetical model was assumed that mentors could improve their mentees' developmental outcomes through positive relationships with mentors as good role models and enhancement of help-seeking orientation. To investigate the mediating effect of process-related outcomes, structural equation modeling was used. The 97 adolescents were recruited through referral and random selection from middle schools in Seoul. The result showed that the effects of program participation were mediated by proximal changes in connectedness to role models and development of help-seeking orientation that, in turn, led to facilitate more positive attitudes toward school and academic activity, and improve psychological outcomes. Practice and policy implications as well as further research topics were discussed to aid the search for highly effective mentoring programs.

• Journal of The Korean Association For Science Education
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• v.43 no.6
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• pp.533-547
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• 2023

This study is an action research aimed at improving the instruction of a teacher educator who teaches science teaching methods to elementary preservice teachers. After identifying the cause of their low levels of curiosity and interest in physics, teaching plans addressing this problem were explored, applied to classes, and reflected upon. Through this process, ways to improve teaching practice in science classes for elementary preservice teachers and pique their scientific curiosity and interest were proposed. A spiral implementation structure that repeats implementation and reflection a total of three times was designed for the prospective preservice teachers who participated in elementary science textbook research physics classes. Self-reports, student participation data, and results from both peer and self-evaluations were collected and analyzed. The reasons for the preservice teachers' low levels of curiosity and interest in science were identified as their inability to recognize and express information gaps and their low levels of willingness to resolve this. Practice expressing information gaps, raising the level of knowledge to be able to recognize information gaps, and a strategy to have the will to resolve information gaps were introduced into the class. To the extent that changes can be made by improving unit classes, elementary preservice teachers can express their curiosity and interest in science through this process.

• Industry Promotion Research
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• v.8 no.4
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• pp.113-122
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• 2023

This study is a research study aimed at finding out the relationship between lifestyle and life satisfaction of single youth households and the relationship between the mediating role of interpersonal relationships and the effect of parents' social and economic status regulation in the relationship between lifestyle and life satisfaction. To this end, this study conducted a self-written survey of single-person youth households across the country through an online survey institution, regardless of gender, and used a total of 501 copies out of 520 subjects for final results analysis. The data were analyzed using the SPSS 25.0 and AMOS 25.0 programs, and the applied statistical techniques included correlation analysis, confirmatory factor analysis, structural equation model analysis, multi-group analysis, and bootstrap. As a result of the study, there was a significant positive (+) correlation between lifestyle, life satisfaction, and interpersonal relationships of single youth households, and interpersonal relationships were found to have a mediating effect in the relationship between lifestyle and life satisfaction. It was found to have a significant positive (+) effect on income and income satisfaction, but the moderating effect of education, economic activity, housing ownership type, and class consciousness was not significant. Based on the results of these studies, it was intended to provide basic data for developing various community programs and institutional arrangements for single youth households.

• Journal of the Korean Society of Radiology
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• v.81 no.4
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• pp.912-919
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• 2020

Purpose This study aimed to compare the brain perfusion status of patients with chronic kidney disease to a normal control group to identify any significant differences. Materials and Methods The perfusion state of the brain was measured by MRI using the arterial spin labeling technique in 36 patients undergoing hemodialysis due to chronic kidney disease and 36 normal controls. Images were then analyzed in a voxel-wise manner to detect brain areas showing significant perfusion differences between the two groups. Results Patients with chronic kidney disease showed increased perfusion in the form of large clusters across the right fronto-parieto-temporal lobe and the left parieto-occipital lobe. In addition, perfusion increased in the bilateral thalami, midbrain, pons, and cerebellum (p < 0.01, familywise error corrected). Conclusion Brain perfusion appears to increase in patients with chronic kidney disease compared to normal controls. Uremic toxicity is thought to be the cause of this increase as it can cause damage to the microscopic blood vessels and their surrounding structures.

• Journal of the Korean Applied Science and Technology
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• v.41 no.2
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• pp.472-483
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• 2024

This study evaluated the attitudes of the Korean population towards sunscreen use through the Health Belief Model (HBM) construct and investigated the psychological factors that influence sunscreen use. For this purpose, an online survey was conducted from 1 November 2023 to 1 January 2024, and a total of 303 participants were collected. The collected data were analysed using SPSS v. 25.0 programme using Cronbach's 𝛼, frequency analysis, descriptive statistics, correlation analysis, independent samples t-test, one way ANOVA, Scheffe's test, and multiple regression analysis. The results of the study showed that the mean score of sunscreen use was 3.26±1.384 out of 5, and there was a significant correlation between the variables of the health belief model and sunscreen use (p<.01). Gender, age, and skin colour were also associated with each variable, with women, the elderly, and those with lighter skin tending to be more proactive in sun protection. Multiple regression analyses revealed that self-efficacy (𝛽=.629, p<.001) and perceived vulnerability (𝛽=.139, p<.001), sub-factors of the Health Belief Model, had a statistically significant positive effect on sunscreen use, while perceived barriers (𝛽=-.261, p<.001) had a statistically significant negative effect on sunscreen use. These results may have important theoretical implications for the development and implementation of educational programmes to promote sunscreen use by providing insight into the psychosocial factors that influence sun protection.