공작기계 주축용 베어링 결함 자동진단시스템의 개발

정의식,강형모,류봉조,임경빈,고준빈,박수규 한밭대학교 산업과학기술연구소 1995 논문집 Vol.3 No.-

This paper deal with a method of detecting localized defects on taper roller bearing in main spindle of machine tool system. The statistical parameters in time-domain signal processing techniques have been calculated to extract useful features from bearing vibration signals. Emloying these features, the statiscical parameters have been established to detect defects on the rollers of bearings, respectively, and used by the input feature of an artificial neural nerwork. As a result that the proposed bearing defects monitoring system could be successfully performed by using the statistical parameters of acceleration signals.

Centering to the boys' high school team : 남자 고등부를 중심으로 Centering to the boy's high school team

남궁옥,원충희 公州大學校스포츠科學硏究所 1995 스포츠科學硏究所論文集 Vol.- No.9

29 Boy's High school Hockey teams took part in the 36th National Assortment Hockey Championship Series, the 74th national Athletic Meeting and '94 Springtime National man and women Hockey competition which were held in 1993. Investgating the number of shooting and success rate in 43 games, I came to conclusion as follows : 1) In whole shooting, the number of shots in the area D was 48.89%, in the area B was 27.91%, in the area C was 19.07%, in order of shootings (p<.10). Success rate of shooting was about 26% in each A, B and C area, and it was comparatively high. 2) In angle shooting, the area Ⅲ marked 62.78% which was the highest success rate.(P<.10). The area Ⅳ marked 20.37%, and the area Ⅱ 13.19%. The success rate of shooting in the area was Ⅱ, Ⅲ, Ⅳ 23.73%, 23.60%, 20.91% which suggests the balanced distribution. Especially the success rate of shooting in the area I was 50%. and it says that boldness in shooting is very necessary. 3) In many kinds of shootings, penalty corner shooting was 39.44%, assist by pass was 23.89%, loose ball was 14.63%(P< .50). The score of penalty corner shootings was 35.78% which marked the highest goals. In assist by pass, solo dribble, free hit and penalty corner except penalty stroke, the success rate of shooting was 23.75% on the average. 4) At the position of stick used in shooting, fore position was the highest frequeney in use. It was 91.1%(P< .01). One touch action shooting was 59.63% which marked the highest frequency in shooting(P< .05). The rate of score was 51.22%, but in the success rate of shooting, direct action shooting is higher 32.18% than that. 5) Hit and push shooting was 84.07% of the whole shootings. Push shooting was the best in the rate of score(P< .05). In the success rate of shooting, flick shooting(51.35%), was higher than push shooting (27.27%).

Effect of a vertical guide plate on the wind loading of an inclined flat plate

Chung, Kung-Ming,Chou, Chin-Cheng,Chang, Keh-Chin,Chen, Yi-Jun Techno-Press 2013 Wind and Structures, An International Journal (WAS Vol.17 No.5

Wind tunnel experiments were performed to study the wind loads on an inclined flat plate with and without a guide plate. Highly turbulent flow, which corresponded to free-stream turbulence intensity on the flat roof of low-rise buildings, was produced by a turbulence generation grid at the inlet of the test section. The test model could represent a typical solar collector panel of a solar water heater. There are up-stream movements of the separation bubble and side-edge vortices, more intense fluctuating pressure and a higher bending moment in the turbulent flow. A guide plate would result in higher lift coefficient, particularly with an increased projected area ratio of a guide plate to an inclined flat plate. The value of lift coefficient is considerably lower with increased free-stream turbulent intensity.

Stability of Recombinant Plasmids Carrying the stb Locus of E. coli IncFII NR1 Plasmid in E. coli and Yeast

Chung, Kung-Sook,Kim, Choon-Kwang,Kim, Kyu-Won The Microbiological Society of Korea 1993 미생물학회지 Vol.31 No.1

The effect of stb locus of E. COLI IncFII plasmid NR1 on the stability of chimeric plasmids was investigated. First, we have isolated the stability locus (stb) from E. coli NR1 plasmid and then inserted into the three different vectors, pUC8, YRp17 and YEp24. By examining their stability in E. coli and yeast, we showed that the recombinant plasmids containing stb locus were resonably stable. Also, by comparing the amounts of the rDNA fragments per haploid genome with those of the plasmid fragments, we showed they copy number of recombinant plasmids was not increased. Consequently, the stb locus of E. coli IncFII plasmid NR1 stabilized the chimeric plasmids but did not affect the replication or copy number of plasmids.

Treating Uncertainties in a Nuclear Seismic Probabilistic Risk Assessment by Means of the Dempster-Shafer Theory of Evidence

Chung-Kung Lo,N. PEDRONI,E. ZIO 한국원자력학회 2014 Nuclear Engineering and Technology Vol.46 No.1

The analyses carried out within the Seismic Probabilistic Risk Assessments (SPRAs) of Nuclear Power Plants (NPPs) areaffected by significant aleatory and epistemic uncertainties. These uncertainties have to be represented and quantifiedcoherently with the data, information and knowledge available, to provide reasonable assurance that related decisions can betaken robustly and with confidence. The amount of data, information and knowledge available for seismic risk assessment istypically limited, so that the analysis must strongly rely on expert judgments. In this paper, a Dempster-Shafer Theory (DST)framework for handling uncertainties in NPP SPRAs is proposed and applied to an example case study. The maincontributions of this paper are two: (i) applying the complete DST framework to SPRA models, showing how to build theDempster-Shafer structures of the uncertainty parameters based on industry generic data, and (ii) embedding Bayesianupdating based on plant specific data into the framework. The results of the application to a case study show that the approachis feasible and effective in (i) describing and jointly propagating aleatory and epistemic uncertainties in SPRA models and (ii)providing ‘conservative’ bounds on the safety quantities of interest (i.e. Core Damage Frequency, CDF) that reflect the(limited) state of knowledge of the experts about the system of interest.

Effect of a vertical guide plate on the wind loading of an inclined flat plate

Kung-Ming Chung,Chin-Cheng Chou,Keh-Chin Chang,Yi-Jun Chen 한국풍공학회 2013 Wind and Structures, An International Journal (WAS Vol.17 No.5

Wind tunnel experiments were performed to study the wind loads on an inclined flat plate with and without a guide plate. Highly turbulent flow, which corresponded to free-stream turbulence intensity on the flat roof of low-rise buildings, was produced by a turbulence generation grid at the inlet of the test section. The test model could represent a typical solar collector panel of a solar water heater. There are up-stream movements of the separation bubble and side-edge vortices, more intense fluctuating pressure and a higher bending moment in the turbulent flow. A guide plate would result in higher lift coefficient, particularly with an increased projected area ratio of a guide plate to an inclined flat plate. The value of lift coefficient is considerably lower with increased free-stream turbulent intensity.

Effect of Reynolds number on compressible convex-corner flows

Chung, Kung-Ming,Chang, Po-Hsiung,Chang, Keh-Chin Techno-Press 2014 Advances in aircraft and spacecraft science Vol.1 No.4

An experimental study was conducted to investigate the effect of Reynolds number on compressible convex-corner flows, which correspond to an upper surface of a deflected flap of an aircraft wing. The flow is naturally developed along a flat plate with two different lengths, resulting in different incoming boundary layer thicknesses or Reynolds numbers. It is found that boundary layer Reynolds number, ranging from $8.04{\times}10^4$ to $1.63{\times}10^5$, has a minor influence on flow expansion and compression near the corner apex in the transonic flow regime, but not for the subsonic expansion flow. For shock-induced separated flow, higher peak pressure fluctuations are observed at smaller Reynolds number, corresponding to the excursion phenomena and the shorter region of shock-induced boundary layer separation. An explicit correlation of separation length with deflection angle is also presented.

A Note on Proximity Mapping

Chung, Woon Kung 건국대학교 1984 學術誌 Vol.28 No.2

Separated K0-Proximity space에서 Proximity mapping을 정의하고, Proximity mapping이 지니고 있는 몇가지 성질을 유도하였다. 특히 Urysohn proximity mapping의 존재성을 K0-proximity structure를 이용하여 증명을 시도하였다.

만성 호산구성 백혈병 1례

정승문,김창욱,허경무,김미자,전용준,이호준,이호영,정회상,박유환,정춘해 朝鮮大學校 附設 醫學硏究所 1996 The Medical Journal of Chosun University Vol.21 No.2

Chronic eosinophilic leukemia is a rare myeloproliferative disorder, It is considered by some to be a variant of chronic myelogenous leukemia. Still, others classify persistent eosinophilia accompanied by an unexplained organ system dysfunction with no underlying cause, under the broad classification of hypereosinophilic syndrome. It is characterized by a persistent eosinophilia of an immature form due to the infiltration of tissue by eosinophil and hepatosplenomegaly, anemia, thrombocytopenia and a brief clinical course. We report a case of eosinophilic leukemia. A 72-year-old man presented anorexia, dizziness and generalized weakness. The peripheral blood showed persistent eosinophilia of an immature form, anemia and thrombocytopenia. The bone marrow study showed a shift to the left, with many eosinophilic myelocyte and marrow fibrosis. The LAP score and chromosome analysis showed normal findings.

북한이탈주민의 차별경험과 적응의 관계

정윤경(Chung, Yun Kung),김희진(Kim, Hee Jin),최지현(Choi, Ji Hyeon) 경성대학교 사회과학연구소 2015 社會科學硏究 Vol.31 No.2

본 연구의 목적은 북한이탈주민들이 남한사회에서 경험하는 차별과 사회적응의 관계를 살펴보고, 그 두 변수를 매개하는 자활효능감의 효과를 검증하는 것이다. 이를 위해 서울시와 경기도, 인천 지역에 거주하고 있는 북한이탈주민을 대상으로 설문조사를 실시하였고 총 405명의 자료를 최종 분석에 사용하였다. 연구 결과, 북한이탈주민들이 느끼는 차별경험이 높을수록 이들이 남한사회에 적응하는 것이 더 힘들어진다는 것이 확인되었다. 또한 북한이탈주민이 느끼는 차별경험이 그들의 자활효능감에 부정적으로 영향을 미치고 있다는 것이 검증되었다. 아울러 북한이탈주민이 경험한 차별과 사회적응의 관계에서 북한이탈주민의 자활효능감이 가지는 부분매개효과가 확인되었다. 이는 북한이탈주민이 남한사회에서 느끼는 차별경험이 그들의 사회적응에 직접적으로 부정적인 영향을 미치는 것과 함께, 북한이탈주민의 차별경험이 그들의 자활효능감을 낮추는 요인으로 작용하여 자활효능감이 감소되면서 이것이 다시 사회적응을 어렵게 하는 경로를 설명하는 것이다. 이러한 연구결과를 토대로 남한사회에서의 일상생활 속에서 북한이탈주민들이 느끼는 차별적 경험을 감소시키고 그들의 자활효능감을 향상시킴으로써 사회적응력을 제고할 수 있는 방안을 모색하였다. This study investigated the relationship between perceived discrimination and social adaptation and the mediating effect of self-support efficacy among North Korean refugees. We analyzed the data of 405 North Korean refugees who resided in Seoul, Gyeonggi Province and Incheon. The result indicated that perceived discrimination was negatively associated with social adaptation among North Korean refugees. Their experience of discrimination was negatively associated with social adaptation, and their self-support efficacy had a partial mediating effect in the relationship between perceived discrimination and social adaptation. This means that perceived discrimination has not only direct effects on social adaptation, but also has indirect effects on social adaptation through self-support efficacy as a mediator. This study presented practical suggestions for reducing their discrimination experience and boosting their self-support efficacy among North Korean refugees in South Korea.