반도체 레이저의 이득 스위칭에 의한 초단 펄스 발생

이상훈,명승일,이명우,서동선,소대화 명지대학교 대학원 1997 대학원논문집 Vol.1 No.-

반도체 레이저의 이득 스위칭에 의한 초단 펄스 발생에 대해 체계적으로 연구하였다. 즉, 동작 파라메터인 DC 바이어스 및 RF 정현파 전력에 따른 초단 이득 스위칭된 출력 펄스의 특성을 조사하였다. 최적의 펄스는 문턱 전류 부근의 DC 바이어스에서 얻어졌으며, RF 전력이 클수록 이 최적의 DC 바이어스는 감소하였다. 출력 펄스 폭은 RF 전력이 증가할수록 DC 바이어스의 변화에 덜 민감하게 나타났다. We study systematically on short pulse generation from a semiconductor laser by gain-switching. We examine the dependence of gain-switched pulse characteristics on the operating parameters, such as DC bias and RF power. The optimum short pulses are obtained around threshold DC bias. As the RF power increases, The DC bias to show shorter pulse width decreases slightly and the pulse width becomes less sensitive to the variations of the DC bias.

고로슬래그 광촉매(TiO₂)담채를 이용한 시멘트몰탈의 질소산화물(NOx) 및 포름알데히드(HCHO)제거특성

이동범,김광련,김화중 대한건축학회 2004 대한건축학회 학술발표대회 논문집 - 계획계/구조계 Vol.24 No.1(구조계)

That used photocatalyst carrier of blast-furnace slag powder and photocatalyst powder which was plastered from high temperature, this research investigated removal quality to NOx which become the cause of air pollution and HCHO which got out construction materials of a new building and tried to analyze the effect which photocatalyst carrier caused in the cement mortar, As a result of above, it will be raised the utility value of photocatalyst, it will be used the environment material.

Coproporphyrin 簡易 定量法의 改善에 關한 硏究

李昌和,宋東彬,車喆煥 고려대학교 의과대학 1984 고려대 의대 잡지 Vol.21 No.1

Rimington (1971) developed a satisfactory method for quantitative determination of urinary coproporphyrin (CP), which is essentially needed for diagnosis of lead poisoning in suspected persons. But it is found to be unsuitable for a mass screening because it is Iaborious and complex in its procedures. Soulsby (1974) modified the method into a simple and convenient one by reducing the steps in extraction procedure. In spite of its simplicity and usefulness for screening purpose, aythor experienced that CP determination by the method was inconsistent and erroneous. Thus, it was not satisfactory and acceptable if accurate determination of CP is needed as in screening test for lead poisoning. The present study was performed to find a simple and accurate method that is applicable for the quantitative determination and mass screening by modifying Soulsby’s method. The results were as follows: 1. The amount of CP extracted with diethylether was shown to be highly dependent on urine pH, when extraction was performed one time instead of three times. The optimal pH was 5.4 where 98% of CP was recovered with one time extraction. 2. When the diethylether layer was washed with distilled water, it was possible to avoid interference in UV-spectrophotometry caused by contaminated organic materials. 3. With modification as above, average recovery rate of CP from urine was 99.5% with a coefficient of variance 2.1% on vaiidity test. 4. The results suggested that Soulsby’s method can be improved to a method with both simplicity and accuracy by simple modifications, i.e., one time extraction with adjusting the urine pH to 5.4 and washing the diethylether later containing CP with distilled water.

황산산성 용액에서 기체 발생 속도에 의한 히드라진과 요오드의 반응속도에 관한 연구

이송주,박동화 광주보건대학 1989 論文集 Vol.14 No.-

We have studied the kinetics of the N₂H₄=l₂ reaction in sulfuric acid media by gas evolution Choi?? has explained that the reaction of N₂H₄-Br₂processes through the Competitive Consecutive Second order reaction mechanism, and we have assumed N₂H₄-l₂ reaction processes through the same mechanism. The rate constant(k'₁) was found to be 0.87~0.98X 10^(-1) M^(-1) sec^(-1) with change in [N₂H₄]_(0), [l₂]_(0), 2a(=2[N₂H₄3_(0)-(l₂]) and inversely proportional to hydrogen concentration. we have also found th at, as k₃ is constant, a comparatively stable intermediate is present .

인플레이션 期待下의 貨弊需要

李鐘和,孫東辰 湖西大學校工業技術硏究所 1985 工業技術硏究所論文集 Vol.4 No.-

Milton Friedman argued that physical goods should be regarded as a substitute for money and that higher expected rates of inflation should induce a portfolio shift from money to physical assets. As Friedman has derived his equation, the demand for real balances is a function of the expected rate of inflation in addition to nominal interest rates and real income. A number of empirical studies for different countries have shown that the anticipated rate of inflation has an independent direct effect on the demand for money, other than via interest rates. But in Korea, there are few studies about the role of expected rate of inflation in the demand for money. The purpose of this paper is to test the significance of the sorted-out independent effect of the expected rate of inflation on real balances and to suggest more appropriate monetary policy in such country suffering high inflation as Korea. In this paper a real partial adjustment mechanism of money demand is assumed. And the expected rate of inflation is estimated by the stochastic time series model(ARIMA model). According to the evidence of this paper, the expected rate of inflation exerts significant influences upon money holdings, while nominal rate fo interest has little explanatory power in money demand function. This confirms the fact that nominal rate of interest has been under the strict government control and has not reflected the opportunity cost of money holdings in Korea. These results suggest that monetary authority should control money supply more carefully in Korea, where everyone has inflationary expectations. In further studies particular emphasis should be given on the mechanism of price expectations formation associated with the appropriate specification of the money demand function and the correct forecast of the effect of monetary policy.

흉선 종양과 관련된 중증근무력증의 임상적 특성

강동화,김호진,김지수,이근호,이광우 대한신경과학회 1998 대한신경과학회지 Vol.16 No.4

무용동작 수행 결정요인 분석

이동옥,임청하 건국대학교 교육연구소 2001 論文集 Vol.25 No.-

The study was designed to identify how the factorial structure for Deciding performance of Dance Movement. The subjects participating in this study were 31 women who was experienced the Dance. In order to accomplish this purpose, the 9 selected Dance Movement test were conducted to S college in Seoul. Factor analysis was applied for analyzing factorial structure of Dance Movement The implications of the study were was as follows ; 1.Among the factors of Dance Movement, Agility gad a significant impact. 2.At the excellent Dance Movement, Agility, Balance, Flexibility were very important factors for deciding performance outcomes.

위궤양, 위선종 및 위선암종 주변 Helicobacter pylori 위염에서 nitrotyrosine 발현 및 아포프토시스

이성희,진소영,이동화 순천향대학교 2001 Journal of Soonchunhyang Medical Science Vol.7 No.1

Purpose: To evaluate whether the increased risk of development of gastric carcinoma due to Helicobacter pylori (H. pylori) infection could be linked with elevated expression of peroxynitrite and apoptosis, we examined expression of nitrotyrosine, a marker for peroxynitrite; MIB-1, a marker for cell proliferation; and TUNEL index, a marker for apoptosis. Materials and Methods: We obtained gastric antral biopsies from 31 patients before and after anti-H. pylori eradication therapy. We examined MIB-1 proliferation index and expression of nitrotyrosine by immunohistochemistry, and apoptosis by TUNEL. Also, we examined H. pylori gastritis using gastric biopsy from 17 patients with gastric adenoma and from 22 patients with adenocarcinoma. Results: After eradication therapy of H. pylori gastritis, significant improvement in both activity and H. pylori count was observed(p<0.05). MIB-1 proliferation index, nitrotyrosine expression, and apoptosis index were similar among H. pylori gastritis with peptic ulcer, gastric adenoma, and adenocarcinoma. These data of H. pylori gastritis with peptic ulcer were decreased after eradication therapy. Conclusion: This study suggest that H. pylori infection is accompanied by the formation of endogenous reactive nitrogen intermediates. DNA damage induced by persistent and repeated inflammation could be reduced by eradication therapy against H. pylori. Key Words : Helicobacter pylori gastritis, Nitrotyrosine, Apoptosis, Proliferation index, Gastric adenocarcinoma

각종 난치성 혈액 질환에서의 비혈연간 골수이식

김동욱,한훈,김정아,김희제,민창기,엄현석,최정현,이종욱,한치화,홍영선,최일봉,신완식,민우성,김학기,김춘추,김원일,김동집 대한조혈모세포이식학회 1997 대한조혈모세포이식학회지 Vol.2 No.1

목적: 비혈연간 골수이식은 혈연내에 적절한 골수공여자가 없는 만성골수성백혈병, 고위험군의 급성별혁병, 면역억제치료에 실패한 재생불량성빈혈 및 각종 난치성 조혈모세포질환의 완치를 위한 표준적인 치료방법으로 정착되고 있다. 혈연간 표준적인 동종 이식에 비하여 비혈연간 이식시에는 생착부전, 이식편대숙주반응과 감염이 더 빈번하게 발생하며, 국내에서는 아직까지 체계적인 임상연구결과가 보고된 바 없었다. 이에 본 센터에서는 1995년 10월 이후로 약 20개월간 26예의 비혈연간 골수이식을 시행하였으며 3개월 이상의 추적관찰이 가능하여 이식초기 합병증의 관찰 및 분석이 가능하였던 20예의 환자를 대상으로 이식성적 및 문제점을 보고함으로써 새롭게 확대되고 있는 이 분야의 임상연구 및 진료의 활성화를 꾀하고자 한다. 방법: 각종 혈액 종양질환으로 비혈연간 이식을 시행한 총 26예의 환자중 3개월이상의 추적관찰이 가능하였던 20예를 대상으로 후향적으로 임상경과를 분석한 후 생존 분석을 시행하였고, 환자의 연령, 성별, 질병의 상태, 조식 적합 항원의 일치정도, 이식편대 숙주 반응의 유무와 생존기간과의 상관관계를 살펴보았다. 또한 표준위험군과 고위험군으로 나누어 생존율을 비교하였고 이식과 관계된 생착 부전, 이식편대숙주반응, 감염의 발생과 양상 그리고 그 합병증을 관찰하였다. 결과: 1. 환자와 공여자간에 HLA 불일치가 20예 중 4예에서 있었으며, 생착여부의 확인이 가능했던 17예 중 16예에서 생착이 확인되어 94.1%의 생착율을 보였다. 2. 급성이식편대숙주반응은 62.5%(10/16예)에서 발생하였으며 111도 이상의 급성의 이식편대숙주 반응은 25%(4/16예)에서 발생하였다. 만성이식편대숙주반응은 40%(2/5예)의 환자에서 발생하였으며 이들 모두 국소형으로 중증의 진행형 만성이식편대숙주반응이 관찰된 환자는 없었다. 3. 호흡기 합병증은 10예(50%)에서 발생하였으며 감염성 폐렴을 포함한 호흡기 합병증이 가장 흔한 일차적인 사망 원인이었다. 호흡기 합병증이 발생했던 10예중 6예가 감염에 의한 폐렴이 의심되었고 나머지 4예는 특발성 간질성 폐렴이었다. 4. 8.5개월의 중앙추적기간 중 35%의 생존율을 관찰할 수 있었고, 생존기간은0.5개월에서 15개월 (중앙치:4개월)이었다. 한편 고위험군은 25%(3/12예), 표준위험군은 50%(4/8)의 생존율을 관찰할 수 있었다. 5. 가장 흔한 사망 원인은 감염성 폐렴을 포함한 호흡기 합병증(6예)이었고, 이외의 사망 원인으로는 급성 이식편대숙주반응과 다장기부전이 각각 2예, 생착 부전, 간정맥 폐쇄, 그리고 재발이 각각 1예였다. Unrelated bone marrow transplantation(UBMT) has been increasingly recognized as the standard treatment for cure of chronic myelogenous leukemia, high risk acute leukemia, aplastic failed on immunotherapy, and the variety of refractory hematologic diseases in patients lacking a related donor. However, as compared to HLA identical sibing transplantation, UBMT carries higher incidence of graft failure, graft versus host disease(GVHD), and infection. In our center, 26 patients underwent UMBT between October 1995 and June 1997. The minimum follow-up of 3 months was possible in 20 patients, for whom early complications and clinical outcomes were assessed. The median age of the 20 patients was 24 years. 8 patients had standard risk disease and 12 patients had high risk disease. All patients received various preparative regimens including total body irradiation according to disease and disease status. 19 patients received CsA + short course MTX for GVHD prophylaxis. One patient received marrow that was depleted of T cells ex vivo using avidinbiotin column. The class I loci were typed by serological methods and HLA-A, HLA-B and HLA-DRB1. 3 additional pairs were one minor mismatched at the HLA-B locus. Another one patients was one major mismatched at the DRBI alleles. 17 patients were evaluable for engraftment. Successful enfraftment was confirmed in 16 patients(94.1%). Only one patient who was performed one major DRBI mismatched transplants experienced graft rejection. 16 patients were evaluable for acute GVHD. The overall incidence of acute GVHD developed in 4 patients(25%). Five patients were evaluable for the development of Ⅳ acute GVHD developed in 4 patients (25%). Five patients were evaluanle for the development of chronic GVHD. 2 patients(40%) developed limited chronic GVHD. Respiratory complications including pulmonary infection developed in 10 patients(50%) and these complications were the most common primary cause of death. Of these 10patients, 6 had pneumonia due to fungus(4 patients), pacterial (1 patient), and CMV infection (1 patient) and 4(20%) had idiopathic interstitial pneumonitis and/or adult respiratory distress syndrome. The duration of median follow- up was 8.5 months and 7 of 20 patients(35%) are alive at the time of this analysis with survival duration of 0.5 to 15 months(median survival duration: 4 months). The overall survival was 25% (3/12 patients) in high risk group and 50%(4/8 patients) in standard group. From these results, we can predict that the incidence and severity of GVHD in Korea are lesser than multiracial countries and the long-term survival of patients with standard risk disease can approach that of HLA matched sibling transplants. For the past two years, the performance of UBMT has been rapidly increasing and it will be possible to analyze much larger number of patients soon in Korea. In the future the problems of graft failure, GVHD, and infection due to long lasting immunocompromised status will need to be overcome by continued medical research. In addition, the volunteer donor pool will have to be expanded by the promotion of the national awareness of its need.

말초동맥질환에 있어서 혈장 호모시스테인 농도의 의미

최동현,이상목,고석환,홍성화,오수명,윤충,박호철 대한혈관외과학회 2004 Vascular Specialist International Vol.20 No.1