상부요로폐색환자에서 신주사상 분리신기능과 크리아티닌청소치 비율의 비교

정헌영,서기석,김종성 大韓泌尿器科學會 1998 Korean Journal of Urology Vol.39 No.2

살모사 교상 후에 발생한 뇌간 경색

권석범,이병철,배재천,황성희,김대훈 대한신경과학회 1998 대한신경과학회지 Vol.16 No.4

비선형 웹 이송 시스템의 장력제어

윤석찬,백승훈,정진태,한창수 韓國工作機械學會 2000 한국생산제조학회지 Vol.9 No.5

This paper presents the study of the tension control in a web transfer system. In this study the sliding mode controller is applied to a time-varying nonlinear mathematical model. The model was derived to consider the effects of changing the roll rad;us in tension variation during winding and unwinding. The uncertainty in modeling may be due to unmodelled dynamics, on variations in system model. Designed sliding mode controller made the system error always staying in the suggested surface from the beginning. Through this, system is maintained to be robust against a disturbance and uncertainty. To verify the designed controller has a good performance, various inputs such as desired velocity, step input, and trapezoidal input are applied. When the sliding mode controller was used, the system(the tension control) performance was improved comparing to the PID controller. The robustness of the controller with respect to an estimation error was verified through simulations.

UWB용 모노콘 안테나 설계

이성훈,최석호,박종권 한밭대학교 정보통신전문대학원 2004 정보통신전문대학원 논문집 Vol.2 No.1

본 논문에서는 UWB 응용을 위한 변형된 모노콘 형태의 안테나를 제안하였다. 안테나의 크기를 줄이기 위해서 사용된 기술은 슬리브를 이용한 것이다. 제안된 안테나는 UWB응용에 좋은 특성(초 광대역폭, 무지향성 패턴, 작은 그룹 딜레이)을 가진다. We have proposed a modified-monocone antenna for UWB applications(3.1∼10.6GHz). The Sleeve technique is used to decrease the antenna size. The proposed antenna have a good characteristics(ultra-wide bandwidth, omni-directional pattern, and low group delay) for UWB applications.

p-Amino-diphenylamine으로부터 N-phenyl-N'-iospropyl-p-phenylene-diamine의 합성 및 특성

변헌수,전남석 여수대학교 1998 論文集 Vol.13 No.2

We were studied to the preparation and property of N-phenyl-N'-isopropyl-p-phenylene-diamine from p-amino-diphenylamine with the various type of precious metal catalyst : 3% platinum on activated carbon. 5% palladium on activated carbon. In this study, we were obtained to the optimum conditions of reaction step in Lab. The data of Lab test were as follows : the purity of N-pheny-N'-isoprophyl-p-phenylene-diamine from p-amino-diphenyl-amine was 97.0% and the yield of N-phenyl-N'-isoprophyl-p-phenylene-diamine from p-amino-diphenylamine was 97.5%.

고삼투압성 비케톤성 상태의 예후인자

안성훈,김양원,김미란,진헌철,안지영,이상래,류석용,김홍용,김성준,이병권,김경환 대한응급의학회 2001 대한응급의학회지 Vol.12 No.2

Background: A hyperosmolar nonketotic state has been known to have a high mortality, and even now, despite this high mortality, only a few studies of this disease have been performed. We studied the prognostic factors for the hyperosmolar nonketotic state. Methods: We retrospectively studied the cases of 40 patients who were in a hypersomolar nonketotic state when admitted to Sanggye Paik Hospital during the 6-year Period from 1995 through 2000. We divided the hyperosmolar nonketotic patients into two groups, the complete recovery group and the incomplete recovery group, and compared the clinical features, the laboratory findings, and the precipitating factors between two groups. Results: 1) A total of 40 patients were studied: 24 in the complete recovery group and 16 patients in the incomplete recovery group. The mortality rate was 32.5%. 2) No significant statistical difference existed among the clinical features of the two groups, except for the sex(p<0.01). 3) Among the laboratory findings of both groups, analysis revealed that the effective osmolarity was significantly higher among those in the incomplete recovery group(p<0.01). Serum sodium concentration was also significantly higher among those in the incomplete recovery group(p<0.01). Serum creatinine was also significantly higher among those in the incomplete recovery group(p<0.05). Serum bicarbonate concentration, on the other hand, was significantly lower among those in that group(p<0.05).4) Infection was identified as the most common precipitating factor(62.5%). Among the precipitating factors of the two groups, there were significant statistical difference in pneumonia, UTI, and inappropriate glucose control. 5) A significant statistical difference existed among the initial level of consciousness of both groups(p<0.05). 6) The only significant independent factor responsible for prognosis of nonketotic hyperosmolar state patients was the sex. Conclusion: The sex was only significant independent prognostic factor of nonketotic hyperosmolar state patients.

고압 커패시터의 고장 분석을 통한 신뢰도 예측

양석준,김진우,신승우,이희진,신승훈,유동수,장석원 한국비파괴검사학회 2001 한국비파괴검사학회지 Vol.21 No.6

본 논문은 고압 커패시터의 고장분석과 신뢰성 예측 결과를 다루고 있다. 부품의 수명과 고장률을 예측하기 위해서 두 가지 방법으로 고장 모드와 고장 메커니즘을 연구하였다. 에폭시 수지로 성형된 고압 커패시터가 절연내압 시험 하에서 저항이 제로로 되는 고장에 대하여, 근본원인 고장분석 체계를 효과적으로 수립함으로써 고장 메커니즘의 원인을 분석하였다. 특히 세라믹-에폭시 계면에서의 절연파괴 고장 현상이 강조되었으며, 본 연구에서 얻어진 결과의 타당성은 마그네트론에 장착된 고압 커패시터의 열사이클 시험 수행에 의한 가속시험 결과로부터 입증되었다. 시험 결과들은 결함이 있는 로트를 신속히 규명하고 B10수명을 결정하는데 유용하게 사용할 수 있다. 또한, 유전체의 절연파괴에 대해서 부하-강도 간섭모델을 이용하여 고장률을 예측하였다. This paper presents a result of failure analysis and reliability evaluation for high voltage ceramic capacitors. The failure modes and failure mechanisms were studied in two ways in order to estimate component life and failure rate. The causes of failure mechanisms for zero resistance phenomena under withstanding voltage test in high voltage ceramic capacitors molded by epoxy resin were studied y establishing an effective root cause failure analysis. Particular emphasis was placed on breakdown phenomena at the ceramic-epoxy interface. The validity of the results in this study was confirmed by the results of accelerated testing. Thermal cycling test for high voltage ceramic capacitor mounted on a magnetron were implemented. Delamination between ceramic and epoxy, which might cause electrical short in underlying circuitry, can occur during curing or thermal cycle. The results can be conveniently used to quickly identify defective lots, determine B10 life estimation each lot at the level of inspection, and detect major changes in the vendors processes. Also, thd condition for dielectric breakdown was investigated for the estimation of failure rate with load-strength interference model.

고무의 산화방지제인 N-(1,3-dimethylbuthyl)-N'-phenyl- p-phenylene-diamine의 제조 및 특성

변헌수,전남석 여수대학교 1998 論文集 Vol.13 No.2

We were studied to the preparation and the study of property of N-(1.3-dimethyl-butyl)-N'-phenyl-p-phenylene-diamine from diphenylamine by the various synthetic methods : nitrosoation, rearrangement, hydrogenation and reductive alkylation. In this study, we were obtained to the optimum conditions of reaction step and applied the obtained data in Lab. to plant. The data of Lab. test were as follows : the purity of p-amino-diphenylamine from diphenylamine was 97.0% and the yield of p-amino-diphenyl-amine from diphenylamine was 88.0%, the purity of N-(1.3-dimethylbutyl)-N'-phenyl-p-phenylene-diamine from diphenyl-amine was 98.5% and the yield of N-(1.3-dimethylbutyl)-N'-phenyl-p-phenylene-diamine from dipheny-lamine was 98.0%.

표피낭종에 발생한 전염성 연속종 1예

문지훈,문용주,최혜자,윤석권 대한피부과학회 2003 대한피부과학회지 Vol.41 No.6

We present an unusual case of molluscum contagiosum occurring in epidermal cyst on back of a 5-year-old girl. Histology showed an intradermal cyst containing lamellated horny materials and typical molluscum cclls. In Korean literature, 5 such case were reported. We report an additional case of molluscum occurring in epidermal cyst. (Korean J Dermatol 3003;41(6) : 790~792)

Line Drawing Image의 처리와 벡터화 시스템

배석찬,이태헌,신성윤 群山大學校 1996 論文集 Vol.23 No.-

This paper proposes an approach to the segmentation, vectorization and representation of large-size line drawing images. The scaned digital image used to preprocessing and vectorization, resulting data was transffered CAD/CAM system. Processing step was noise removal, void filling, image segmentation, line thinning and contour extraction. Raster-to-vector conversion was performed by recognition and fitting of straight line segments, circles, arcs, and conic section. Experimental results are also shown