• Electric Engineers Magazine
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• s.123
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• pp.48-52
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• 1992

• JOURNAL OF ELECTRICAL WORLD
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• s.444
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• pp.56-61
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• 2013

• The Journal of the Korea institute of electronic communication sciences
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• v.17 no.3
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• pp.459-466
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• 2022

Switching surges are a common type of phenomenon that occur on any sort of power system network. These are more pronounced on long transmission lines and in high voltage converter stations. At AC/DC hybrid transmission lines, the insulation coordination of such lines is mainly dictated by the peak level of switching surges, the most dangerous of which include three phase line energization and AC/DC converter station. The power system structure consist of AC/DC hybrid transmission lines which is combination of AC 765kV and ±500kV HVDC 1 bipole system for contingency analysis. The power system under study and its components are simulated using EMTDC software package, the effects of the various AC/DC mixing power lines are reviewed. The developed models of EMTDC conversion lines based on combination of AC/DC system are simulated and the characteristics of switching surge over-voltage from its results are discussed.

• Korean Journal of Occupational Health Nursing
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• v.29 no.3
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• pp.184-191
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• 2020

Purpose: This study aims to compare the general characteristics, life-style, health examination results, and sick leave days by airmen medical examination decision and to investigate factors affecting sick leave days. Methods: We obtained data from 2,361 Korean pilots who worked for a commercial airline. Comparison of the results by airmen medical examination decision (Fit or waver) was conducted using the 𝝌² test or Fisher's exact test. Factors affecting sick leave days were analyzed using logistic regression. Results: Age, smoking history, blood pressure, obesity, and fasting blood sugar level were significantly different between the Fit and Waver groups. Rate of using sick leave long-term was higher in the Waver than in the Fit. Sick leave days were significantly associated with age, habits of drinking, and smoking in the Fit group. Conclusion: This study demonstrated the health risk factors that affect the number of sick leave days. By providing basic data for the health care of workers, it is expected to be applicable to the provision of health promotion and disease prevention programs for workers.

• 한국HCI학회:학술대회논문집
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• 2008.02b
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• pp.136-139
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• 2008

다양한 기능들이 휴대폰에 집약되고 있음에 따라, 사용자가 메뉴를 간편하게 선택할 수 있도록 도와주는 pointing Device의 역할은 매우 중요해지고 있다. 본 연구는 휴대폰에 내장된 pointing device 중 광센서와 pointing stick에 대한 사용성 평가를 통한 사용자의 조작 효율 및 조작 만족도 향상 요인 도출을 목적으로 하고 있다. 이를 위하여 본 연구에서는 각각의 입력장치가 적용된 휴대폰을 이용하여 객관적 평가와 주관적 평가를 수행하였다. 객관적 평가에서는 Fitts' law를 바탕으로 한 throughput 개념을 이용하여 커서 이동 및 선택 성능을 평가하였다. 또한 주관적 병가에서는 체크리스트를 이용하여 사용자의 수용도(user acceptance)를 평가하였다. 연구 결과, 광센서는 이동 방향에 따라 수행도 차이가 큰 것으로 나타났으며, pointing stick가 광센서에 비해 사용자의 수용도가 높게 나타났다. 본 연구 결과는 추후 실제 휴대폰의 pointing Device 설계 및 적용 시에 유용하게 활용될 수 있을 것이라 예상된다.

• Proceedings of the KIEE Conference
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• 2003.07a
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• pp.199-201
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• 2003

Because of Korean power system characteristics and increasing power demand, the need of 765kV transmission line is growing gradually. Now a days, KEPCO's 765kV transmission line has been tested and stands for commercial operation. During the first stage, 765kV transmission line will be operated with two voltage grades of 765kV and 345kV, which results the unbalance of power system. So unbalanced current such as zero sequence current flows in the transmission line. In this paper, we describes the simulation study of 765/345kV parallel transmission line by using EMTDC program.

• The KIPS Transactions:PartC
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• v.10C no.3
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• pp.265-272
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• 2003

RBAC is an Access Control Mechanism for security administration of system resource and technique attracting in commercial fields because of reducing cost and complexity of security administration in large network. Many RBAC's research is progressive but several problems such as the delegation of role have been pointed out concerning the mechanism. It is necessary that a person's role delegate someone with reliability by reasons of a leave of absence, sick leave and the others. But the existing RBAC standards don't give definition of the delegation of roles. In this paper, we propose RBAC model that delegator can delegate subset of role and permission to a delegatee so that more efficient access control may be available.

• Journal of Korean Medical classics
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• v.19 no.3
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• pp.255-259
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• 2006

음양오행학설시한의리론적근간(陰陽五行學說是韓醫理論的根幹), 소이기의의최중요(所以其意義最重要), 야유허다적함의(也有許多的含意). 특별시오행유불단적상생상극지관계(特別是五行由不斷的相生相克之關系), 병가이순환(幷可以循環). 단재(但在) ${\ulcorner}$황제내경(黃帝內經)${\lrcorner}$ 등의서중(等醫書中), 유관우오행적내용(有關于五行的內容), 허다의가혹불료해기문적함의(許多醫家或不了解其文的含意), 지용오행상생상극적관계이해석(只用五行相生相克的關系而解釋). 대우(對于) ${\ulcorner}$소간 보명전형론(素間.寶命全形論)${\lrcorner}$ 적오행상극적내용(的五行相克的內容), 허다의가야지이오행상극적관계이석지(許多醫家也只以五行相克的關系而釋之), 소이(所以)'사득목이달(士得木而達)'적의난이해명(的意難以解明), 이차불가이유지일관적해석(而且不可以維持一貫的解釋). 소이아고찰료차편대우오행상극지관계(所以我考察了此篇對于五行相克之關系), 이득료여하결론(而得了如下結論). 모일시(某一是), 본편적오행상극지의(本篇的五行相克之意), 불지유극해적의사(不只有克害的意思), 환유요용상극지기거억제기항성적기(還有要用相克之氣去抑制其亢盛的氣), 저양재가이유지오행상호적균형지의(這樣才可以維持五行相互的均衡之意). 기이시(其二是), '토득목이달(土得木而達)'적달자지의(的達字之意), 불요구어자의이석지(不要拘於字意而釋之), 약이달자지의의해석본문(若以達字之意義解釋本文), 실일관적해석이불가이발명본문적의의(失一貫的解釋而不可以發明本文的意義). 기삼시(其三是), '토득목이달(土得木而達)'적의의(的意義), 시토기항성이과우응취적상태(是土氣亢盛而過于凝聚的狀態), 용목적소설효능거소통토기(用木的疏泄效能去疏通土氣). 여차설명법(如此說明法), 병가이설명별적사행지상극관계(幷可以說明別的四行之相克關系).

• The Journal of Korean Philosophical History
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• no.31
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• pp.321-346
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• 2011

This is a preliminary study in order to deal intensively with the overall characteristics of Korean military science in the future days. First off, the history of military science of China based on the precedent studies was recapitulated, and a comparative study on the acceptance process of the books on military art and science, as well as on understanding patterns of literati on the subject through literature searches, ranging from the Three Kingdoms Period to the Goryeo Dynasty in Korean peninsula, was conducted. In case of Korea, the Chinese books on military strategy, including Sun Tzu's the Art of War, had already been passed down during the Three Kingdoms Period, and broadly read by scholarly people. They had utilized diverse methods based on their knowledge of Confucianism. In the reference materials, the authors of Korean military strategy books had greatly relied upon the Chinese books on military strategies, however, they had made the military principles run in their own way. At the end of Goryeo Dynasty, 'Military Science' had been well established as a subject in academia, and this curriculum had been taught not only at the National Confucian Academy, Seonggyun-gwan, in the capital but also at the country public school ("Hyanggyo") in the province together with Confucianism. Because of the limits of reference materials, however, it was difficult to confirm whether or not such strategic experiences were actually led to the publication of the books on military art and science, or how many books on military strategies and tactics had been published up until the end of Goryeo Dynasty. But, the facts that there were not many publications of the books on military strategies during the era of Three Kingdoms and of Goryeo Dynasty don't mean that Korean military science had entirely relied upon the Chinese military art and science. For instance, such strategies, tactics and leaderships as exhibited in the process of the Great Victory at Salsu River ("Salsu Daecheop") achieved by General Eulji Mun-deok, as well as the Great Victory at Gwiju ("Gwiju Daecheop") achieved by General Kang Gam-chan could never happen by chance.

• Journal of Digital Convergence
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• v.16 no.8
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• pp.243-252
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• 2018

The purpose of this study was to examine relationships among disease-related characteristics, symptom stress, quality of life in women with endometriosis, and then to identify predictors of quality of life in them. The self-reported questionnaires were administered to 99 women in one general hospital. As results of multiple regression analysis, the factors affecting quality of life in women with endometriosis were sick leave (${\beta}=-.27$, p=.000) and symptom stress (${\beta}=.59$, p=.000), explained women's quality of life with 57.0% (F=11.39, p<.001). Based on the findings, there is a need to develop a self-care program for chronic pain and a nursing intervention for enhancing a quality of life in women with endometriosis.