Method for Protection of Single‑Line‑Ground Fault of Distribution System with DG Using Distance Relay and Directional Relay

Jung‑Hun Lee,Min‑Su Park,Hong‑Seon Ahn,Kyung‑Won Park,Jun‑Seok Oh,Seung‑Gyu Jeon,Dong‑Kyu Kim,Jae‑Eon Kim 대한전기학회 2020 Journal of Electrical Engineering & Technology Vol.15 No.4

When large scales DG are connected to the distribution system of unidirectional power currents, bi-directional power currents are formed, making it impossible to use conventional overcurrent protection methods alone to detect and isolate fault sections for ground and short-circuit faults. To solve these problems, this study proposed the method of protection against single-line-ground fault of common neutral line multi-contact local power distribution system using distance relay and directional relay. The proposed protection method was applied to the common neutral multi-ground distribution system to validate the protection against single-line-ground fault through the PSCAD/EMTDC software package and efectively detect and isolate only the zone of single-line-ground fault without malfunctions.

Scanning tunneling microscopy investigation of nano-structured α-K5PW11(M x OH2)O39(M = Mn(II), Co(II), Ni(II), and Zn(II)) Keggin heteropolyacid catalyst monolayers.

Choi, Jung Ho,Kang, Tae Hun,Bang, Yongju,Yoo, Jaekyeong,Jun, Jin Oh,Song, In Kyu American Scientific Publishers 2014 Journal of nanoscience and nanotechnology Vol.14 No.11

<P>Nano-structured α-K5PW11(M x OH2)O39 (M = Mn(II), Co(II), Ni(II), and Zn(II)) Keggin heteropolyacids (HPAs) were investigated by scanning tunneling microscopy (STM) and tunneling spectroscopy (TS) measurements in order to elucidate their redox property and oxidation catalysis. HPA molecules formed two-dimensional self-assembled monolayer arrays on highly oriented pyrolytic graphite (HOPG) surface. Furthermore, HPAs exhibited a distinctive current-voltage behavior referred to as negative differential resistance (NDR) phenomenon. The measured NDR peak voltage of HPAs was correlated with the reduction potential and the absorption edge energy determined by electrochemical method and UV-visible spectroscopy, respectively. NDR peak voltage of HPAs appeared at less negative voltage with increasing reduction potential and with decreasing UV-visible absorption edge energy. The correlations strongly suggested that NDR phenomenon was closely related to the redox property of HPAs. Vapor-phase oxidation of benzyl alcohol to benzaldehyde was carried out as a model reaction to track the oxidation catalysis of HPAs. NDR peak voltage appeared at less negative voltage with increasing yield for benzaldehyde.</P>

全羅左水營의 배치특성에 관한 연구

오정훈,남호현 대한건축학회 2003 대한건축학회논문집 Vol.19 No.12

The Cholla-Jwasuyeong is the navy headquarters of local province which was built in the Chosun Period. The aim in this study is a research into the site plan method of the Cholla-Jwasuyoung, a structure built in the Choson Period. The arrangement of the Cholla-Jwasuyoung is a peculiarity of a military base for defense and a structure managed by a government office. The significance of this study is a new departure of research into the site plan method of the naval base, a structure built for military purposes.

진피내 모반, 경계 모반 및 악성 흑생종에서 p53과 Ki-67의 발현 양상

이정훈,양승하,오미혜,김의한 순천향의학연구소 2004 Journal of Soonchunhyang Medical Science Vol.10 No.1

The authors analyzed immunohistochemical expression of mutant p53 and Ki-67 in eleven cases of intradermal nevus, 7 cases of junctional nevus and 6 cases of malignant melanoma, so following results were obtained. Results: 1. The positive reaction of p53 protein was 0%(0/11) in intradermal nevus, 43%(3/7) in junctional nevus and 83%(5/6) in malignant melanoma. 2. The positive reaction of Ki-67 was 9%(1/11) in intradermal nevus and 14%(1/7) in junctiona nevus, but the labelling index were below 10% in both nevi. In malignant melanoma, the positive reaction of Ki-67 was appeared in 50% (3/6). but the labelling index were below 20% in all positive cases Above results suggested that the p53 expression was stronger in poor differentiated tumors, so the p53 protein expression appeared to be related to the histological differentiation degree. But the Ki-67 expression appeared to be more related to the prognosis according to tumor growth rate than histological differentiation degree Because the Ki-67 labelling index was low in malignant melanoma as expected, it was difficult to justify the idea that the growth and prognosis of malignant melanoma were justified only by the Ki-67 positive reaction and labelling index. But the Ki-67 positive cells were not almostly observed in intradermal nevus and junctional nevus, So the differnetial diagnosis between benign and malignant melanocytic tumors were appeared to be possible by Ki-67 positive reaction and labelling index.

IMF에 관련된 경제적 스트레스가 정신 건강에 미치는 영향

유희정,황성훈,홍진표,김헌수,이철,한오수 大韓神經精神醫學會 2000 신경정신의학 Vol.39 No.1

본 연구는 IMF에 관련된 경제적 스트레스가 정신 건강에 미치는 영향과 그 과정을 밝히기 위해 설계되었다. 스트레스 과정에 관여하는 요인으로 사회적 지지와 문제 해결 양식, 그리고 무망감을 도입했으며, 이들에 의해 스트레스의 영향이 매개되는지를 검증하였다. 경제적 스트레스의 수준에 따라 표집된 221명의 일반인들을 대상으로 우울, 불안, 신체화, 적대감, 사회적 지지, 그리고 문제 해결 양식 등을 측정하였다. 가정한 대로 실직으로 대표되는 경제적 스트레스는 정신 건강에 부정적 영향을 미치는 것으로 나타났다. 그 구체적인 양상을 살펴보면 다음과 같다. 먼저, 사회적 지지는, 높은 스트레스 조건에서 증상의 발현을 억제하는 완충 효과가 있음이 입증되었다. 두번째로, 남성이 여성에 비해 경제적 스트레스의 부정적 영향에 더 취약한 것으로 나타났다. 세번째, 경제적 스트레스는 문제 해결 양식의 다양한 구성요소중 문제 해결에 대한 무기력감에만 영향을 미치는 것으로 나타났다. 네번째, 무망감은 경제적 스트레스와 정신 건강간의 관계를 매개하는 변인임이 인과모형 검증을 통해 확인되었다. 끝으로, 이러한 결과가 스트레스 개입 프로그램 개발을 위한 이론적 기초를 제공한다는 의의가 있음을 논의 했고, 본 연구의 몇 가지 한계점을 지적하였다. This study was designed to investigate the influence of the so-called IMF-related economic stress upon the mental health and to analyze the process of the influence. As the possible variables moderating the stress process, social resource, problem solving style, and hopelessness were included. 221 male and female subjects were recruited according to the intensity of economic stress and classified into four groups(employees of solid companies, employees of the companies at risk, short-term unemployed and long-term unemployed). Relevant measures including economic stress scale, selected SCL-90R subscales(somatization, depression, hostility, anxiety), social support scale, problem-solving scale, and job hopelessness scale were administered. As assumed, it was proved that economic stress had adverse effects on the mental health. In addition to this basic causal relationship, moderating effects of several variables were found as follows: First, social support had the buffering effect upon the economic stress. That is, strong social support played the role suppressing the development of psychiatric symptoms under high stress. Second, men were more vulnerable to the adverse effects of economic stresses than women. Third, economic stresses had influence on the helplessness concerning the problem solving. However other problem solving strategies such as creative style, approach style, avoidance style, etc were proven to have no relationship with the economic stress. Fourth, in the analysis of unemployed group, it was found that hopelessness mediates the relationship between economic stress and mental health. In conclusion, the clinical implications of such findings in economic stress process were discussed and several limitations and the suggestions for future researches were also addressed.

이동로봇의 동적 경로계획

이우송,오세봉,안용근,문정훈,한성현 한국공작기계학회 2008 한국공작기계학회 추계학술대회논문집 Vol.2008 No.-

This paper propose a new path planning method for mobile robots. The creation method of the course approaches with the method of the frame line graph base where the calculation time becomes disturbance. The graph composition where is not the static course plan method of existing, a course search and repeats continuously changes a graph and proposes the course the dynamic routing plan method. The method which is proposed is composed of a course creation phase and a course improvement phase, each phase includes a graph composition and a course search process.

忠淸南北道에 捿息하는 翼手類(Chiroptera)의 地理的 分布

孫成源,吳甲守,李守一,李政勳 경남대학교 환경문제연구소 1991 환경연구 Vol.13 No.-

The geographical distribution of Ch'ungch'□ngnam-buk-do chiropteran fauna has not been investigated throughout systematically. In the present study, 216 specimens of Ch'ungch'□ngnam-buk-do bats fauna were collected at 45 localities in city and districts during the period from February 1980 to August 1990. The results are as follows : The species of collecting bats during this period were Rhinolopus ferrumequinum korai, Myotis garcilis, Myotis ikonnikovi, Myotis formosus tsuensis, Myotis daubentoni ussuriensis, Myotis macrodactylus, Pipistrellus abramus, Pipistrellus coreensis, Miniopterus schreibersii fuliginosus, Murina leucogaster intermedia. Therefore, the recent chiropteran fauna in habited in Ch'ungch'□ngnam-buk-do were found as 13 species, which belongs to 6 genera, 2 families, including 3 species of Myotis nattereri bombinus, Eptesicus nilssoni parvus and E. serotinus brachydigitus reported by Kim(1969) and Mori(1928a). The habitats of 2 species of P. coreensis and M. l. intermedia were discorved for the first time in Ch'ungch'□ngnam-buk-do.

주행로봇의 경로제어

이우송,오세봉,안용근,한성현 한국공작기계학회 2009 한국공작기계학회 춘계학술대회논문집 Vol.2009 No.-

This paper propose a new path planning method for mobile robots. The creation method of the course approaches with the method of the frame line graph base where the calculation time becomes disturbance. The graph composition where is not the static course plan method of existing, a course search and repeats continuously changes a graph and proposes the course the dynamic routing plan method. The method which is proposed is composed of a course creation phase and a course improvement phase, each phase includes a graph composition and a course search process.

土木工學敎育科 敎育改善에 關한 硏究

金八圭,鄭海駿,權五憲,姜準默,林熙大 충남대학교 공업교육연구소 1981 論文集 Vol.4 No.1

Korea enters a new era of industrial modernization, spurred by her successive five-year economic development plans. The labor-intensive light industry that led the nation's economy in the past decades is undergoing a gradual shift to the technology-intensive heavy and chemical industry. The demand for industry-minded young technician is thereby ever mounting in number in various industrial sectors, which in turn creates many challenging issues on Civil Engineering Education. Among them, this paper deals exclusively with the curriculum of the Department of Civil Engineering Education. As the results of a trade analysis for graduates from technical high schools, it was realized that current curriculum were somewhat isolated from outside environment and found too rigid to meet the changing requirements. Needless to mention, teachers play a vital roles in the technician education. Accordingly the teacher must be qualified well not only in knowledge on the major subjects but also in practices. The improvement of current curriculum is strongly recommended to produce qualified teachers, taking into account the changing social demands. This study is very limited in terms of finance, time allowance and manpower. Accordingly the model curriculum was based on the trade analysis, social requirements and the current curriculum, and its justification was not verified by tests and broad reviews.

The HBV DNA Amounts in Serum Have No relationship with ALT level and Hetergeneous Population Coexits in Chronic Hepatitis B Virus Infection

Chun, Yoon-Keun,Ha, Joo-hun,Hong-Jung-Woo,Oh, Soo-Myung,Kim, Sung-Soo 경희대학교 동서의학연구소 1999 INTERNATIONAL SYMPOSIUM ON EAST-WEST MEDICINE Vol.1999 No.1

Yoon-Keun Chun¹,Joohun Ha□Hong-Jung Woo□, Soo Myung Oh□,Sung Soo Kim□ ¹Department of Molecular Biology, College of Medicine,²Department of Surgery, college of Medicine,³Department of Internal Medicine, College of Oriental Medicine,and ⁴East-Weat Medical Reserch Institute,Kyung Hee University, Seoul, Korea. The HBV DNA Amounts in Serum Have No relationship with ALT level and Hetergeneous Population Coexits in Chronic Hepatitis B Virus Infection. Proceedings of International Symposium on East-West Medicine, Seoul. 212-230, 1999. -Hepatitis B is caused by hepadnavirus. Hepatitis B virus replicates through 3.5kb pregenomic RNA intermediate which is regulated by core promoter. Pathogenesis of hepatitis B virus has been bilieved the result of host immune response. But recently many studies have reported that high level of viral replication caused by mutation in core promoter might result in severs hepatitis. But these studies were performed in vitro, not in vivo. So there is yet debate about which factor, viral of host factor, is more important in pathogenesis of hepatitis B virus. So we measured real viral replication level in 204 chronic hepatitis B patients by quantifying HBV DNA from sera by our novel PCR-based more sensitive method, and compared these results with ALT level measured from same sera, which indicates liver cell damage. Surprisingly there are no significant correlation between HBV DNA quantity and ALT level. Then we cloned core promoter region. In SSCP, we found that many viral mutants coexist in one patient. Base on SSCP result, we chose main viral core promoter type in each patients, which is thought to determine overall viral replication level in this patient. Main type of core promoter region of each 41 patients were directly sequenced. And with these we measured promoter activity by luciferase assay system and compared promoter activity with on another. We found tha there were some differences in promoter activity according to core promoter sequences. And we constructed replication-competent viral constructs with core promoter from 41 patients and Transfected these into HepG2 cell and measured HBV DNA by southern blot. There were also differences in HBV DNA quantity according to core promoter sequences. On these all results we investigated correlation between the effect of HBV core promoter on viral replication in vitro and HBN DNA quantity, ALT level from sera of each patients. We found there is no significant correlation among them. As a result, we concluded that in determining severity chronic hepatitis B patients, host factors of each patient is more important rather than replicative activity of virus itself.