지하철의 사상사고 및 운전장애 분석에 관한 연구

이동훈,목연수,장성록,권혁무,윤원영,옥영석,최용석,배동철 한국산업안전학회 1999 한국안전학회지 Vol.14 No.3

The purpose of this study is to analyze death injuries and operation troubles of urban transit. No difference was shown in death rates between Line 1 of Pusan urban transit and Line 5, 7, and 8 of Seoul metropolitan transit. And relief time by another train did not depend upon the number of crews. We concluded that thorough inspection and preventive maintenance of trains and facilities are necessary for safe and timely service of urban transit.

조사료의 종류가 홀스타인 송아지 유선의 발달 , 반추위 돌기 및 성장률에 미치는 영향

조광근,최윤재,박영우,윤연화,한영근,윤상기,권웅기 한국영양사료학회 1999 韓國營養飼料學會誌 Vol.23 No.6

본 연구는 홀스타인 송아지에 대한 세 종류의 조사료가 유선조직, 반추위 유두, 번식성적 및 성장률에 미치는 영향을 조사하기 위하여 실시하였다. 출생 후 4일된 송아지(42.9±0.9㎏) 24두를 무작위로 선발하여 출생 후 4∼44일까지 전유를 급여하다가 45일에 그룹 1은 볏짚, 그룹 2는 오차드 그래스, 그룹 3은 알괄파를 급여하였다. 또한 유선조직과 반추위의 발달을 측정하기 위하여 3, 9, 18개월령에 도달하였을 때 각 처리구의 송아지를 1마리씩 도살하였다. 알팔파를 급여한 그룹 3은 다른 처리구에 비하여 중체율이 높았으며, 그룹 2는 영양소 이용률과 번식성적이 높은 경향을 나타내었다. 반추위의 무게는 3개월령 도달시에는 그룹 3이 가장 무거웠으나, 9개월과 18개월령 도달시에는 그룹 2에서 가장 무거운 것으로 나타났다. 반추위의 유두 수는 유두의 성장과 함께 일반적으로 감소하는 경향을 나타내어 유두의 길이와 유두 수와는 서로 상대적인 관계를 나타내었다. 유선의 기능적 활성을 나타내는 RNA/DNA 함량은 3개월 시에는 그룹 3이 가장 낮은 경향을 보였으나 9, 18개월 시에는 반대로 가장 높은 경향으로 나타났으며, 유선세포의 크기를 나타내는 protein/DNA 함량은 18개월 시에 그룹 2가 가장 높은 경향을 보였다. 결론적으로 본 연구에서 볏짚은 반추위의 초기 발달을 촉진하고 알팔파와 오차드그래스는 성장과 번식성적을 증가시키며 또한 초기에 유선의 발달을 촉진시키는 것으로 나타났다. Twenty-four Holstein calves were used to evaluate the effects of three different forages on growth and reproductive performances, and ruminal papillary and mammary developments. Four-day-old Holstein calves weighing 42.9±0.9 ㎏ were randomly assigned to three forage groups of rice straw (group 1), orchard grass hay (group 2), and alfalfa (group 3). All calves received whole milk from day 4 through day 44. At 45 days of age, the animals were assigned at random to one of the three dietary treatments. When calves reached the ages of 3, 9, and 18 months, one calf in each group was sacrifced for evaluation of ruminal and mammary tissue developments. Calves of group 3 gained more body weight than those of other groups, while group 2 showed an effective nutrient utilization and reproduction performance. At 3 months, the stomach weight of group 3 was the highest, however, group 2 provided the highest stomach weight at 9 and 18 months. A remarkable reduction in papillae number was observed in the rumens of all 3- to 9-month-old heifers. A decrease in number of these papillae was observed in all groups exhibiting papillary growth. There was a reciprocal relationship between the number and the length of ruminal papillae. Among the 3-month-old calves, the functional activity (RNAI DNA contents) of the mammary glands of group 3 was lower than those of other groups, whereas the trend was opposite for 9- and 18-month-old heifers. The size of mammary cell (protein / DNA contents) was the greatest for group 2 at 18 months of age. The results suggest that rice straw stimulated earlier development of rumen. Alfalfa and orchard grass improved the growth, reproduction performance, and earlier development of mammary glands.

CBD 방법에 의한 CdS1-xSex 박마의 열처리에 따른 광전기적 특성

문종대,정태수,신현길,김택성,신영진,홍광준,유상하,서상석,최승평,이상열,신용진,이관교,김혜숙,윤은희,김승욱,전승룡 한국센서학회 1995 센서학회지 Vol.4 No.1

Polycrystalline CdS_(1-x)Se_x, thin films were grown on ceramic substrate using a chemical bath deposition method. They ere annealed at various temperature and X-ray diffraction patterns were measured by X-ray diffractometer in order to study CdS_(1-x)Se_x, polycrystal structure using extrapolation method of X-ray diffraction patterns for the CdS. CdSe samples annealed in gas at a 0 it was found hexagonal structure which had the lattice constant a_0=-4.1364Å, c_0=6.7129Å in CdS and a_0=4.3021Å, c_0=7.3021Å in CdSe. respectively. Hall effect on these samples was measured by Van der Pauw method and then studied on carrier density and mobility depending on temperature. We measured also spectral response, sensitivity(γ), maximum allowable power dissipation and response time on these samples.

Cd1-xZnzS 박막의 성장과 광전도 특성

문종대,정태수,신현길,김택성,이충일,홍광준,이상열,서상석,신용진,김혜숙,윤은희,김승욱,전승룡,유상하,이관교,박향숙,신영진 한국센서학회 1995 센서학회지 Vol.4 No.3

Polycrystalline Cd_(1-x)Zn_xS thin film were grown on slide glass(corning-2948) substrate using a chemical bath deposition (C.B.D) method. They were annealed at various temperature and X-ray diffraction patterns were measured by X-ray diffractometor in order to study Cd_(1-x)Zn_xS polycrystal structure using extrapolation method of X-ray diffraction patterns for the CdS, ZnS sample annealed in N₂ gas at 550 ℃. It was found hexagonal structure which had the lattice constant a_o = 4.1364Å, c_o=6.7129Å in CdS and a_o = 3.8062Å, c_o = 6.2681 Å in ZnS, respectively. Hall effect on these sample was measured by Van der Pauw method and then studied on carrier density and mobility depending on temperature. We measured also spectral response, sensitivity maximum allowable power dissipation and response time on these sample

다이캐스팅한 SiC 입자강화 알루미늄 복합재료의 피로균열 전파특성

김송희,윤여범,이기호,오준도,주희위,이지환 대한금속재료학회(대한금속학회) 1998 대한금속·재료학회지 Vol.36 No.8

This study is to investigate the effect of load ratio on fatigue crack of die-cast SiC particulate aluminum composites. Fundamental fatigue crack propagation tests were performed with sub-sized C-T specimens at a load ratio of 0.1, 0.3 and 0.5 respectively. Crack closure measurements were conducted for explaning the effect of load ratio on fatigue crack growth. The experimental results showed that the fatigue crack growth rate increases with the load ratio, especially at near threshold. The composite reinforced with 20 vol.% SiC particles was better in fatigue crack growth resistance than that with 10 vol.% SiC particles. Through the measurement of Kop and ΔK at various R ratios the concept of effective stress intensity factor range ratio. U was reviewed to evaluate the stress ratio effect on fatigue crack growth. Relationships between U and variables such as ΔK and R were obtained empirically so that we could predict ΔK_(eff) that is of critical importance for the prediction of fatigue crack propagation rate.

S . L . E . 환자 혈액에서 분리한 Listeria monocytogenes 의 세균학적 특성

김혜숙,정윤섭,이삼열 대한미생물학회 1973 大韓微生物學會誌 Vol.8 No.1

Listeria monocytogenes human infection is a relatively rare disease which usually is meningitis in newborn babies. The organism was isolated from blood cultures of a 52 year old female patient with meningitis. It was considered that the underlying disease, I.e. S.L.E., and the steroid therapy which the patient had been receiving played some role for the Listeria infection. The isoIate was showing characteristics of L. monocytogenes, I.e. diphtheroid like morphology, motility with four peritrichous flagella, hemolytic small colonies on blood agar, growth in the presence of 7. 5% salt and at 4 C, and inducing monocytosis in an experimentally infected rabbit. Serologically the organism was identified as L. monocytogenes 4b. The isolate was showing susceptibility to many antibiotics tested including ampicillin, penicillin and tetracycline which were the recommended drugs of choice for the treatment of Listeriosis. It is the general opinion that Listeriosis is not so rare as literatures are showing. It is considered that some of the isolate of the organism from clinical specimens are mistakenly discarded due to the fact that the organism shows diphtheroid like morphology and that not many laboratories are able to recognize the organism. Literatures are seen which emphasize more careful examination of gram positive bacilli with diphtheroid like morphology especially when they are isolated from blood or from spinal fluid of patient.

TiNi 가 섬유가 TiNi (Co)/Al 형상기억복합재료의 피로균열전파에 미치는 영향

박영철,윤두표,김순국,이준희,이규창 대한금속재료학회(대한금속학회) 1999 대한금속·재료학회지 Vol.37 No.5

In this paper, TiNiCo/Al shape memory composites were fabricated by powder metallurgy method. TiNi and TiNiCo were used as fiber for reinforcement. To investigate the fatigue crack propagation behavior due to the compressive residual stress which exists in the composites, fatigue test was performed at room temperature and above the inverse transformation temperature A_f of TiNi and TiNiCo shape memory alloy. Results are as follows; At 363 K, both composites have lower fatigue crack propagation rate than pure matrix in the same ΔK area and the fatigue crack propagation of TiNi/Al composite is lower than that of TiNiCo/Al composite.

울산공단지역의 대기중 휘발성 유기화합물에 대한 위해도 평가

이진홍,남병현,윤미정 한국산업안전학회 1999 한국안전학회지 Vol.14 No.2

This study focused on risk assessment for inhalation of airborne volatile organic compounds (VOCs) in Ulsan industrial complex area. For non-carcinogenic risk, even the highest hazard index of toluene was estimated to be 4.8 × 10^(-2), which was much lower than 1. The total hazard index of VOCs was estimated to be 5.8 × 10^(-2). However, lifetime average cancer risk from the inhalation of airborne VOCs was estimated to be about 1.1 × 10^(-3), which was much higher than a risk standard of 10^(-5). The risk of 4.4 × 10^(-5) came from benzene, the only human carcinogen among VOCs, while that of 1.05 × 10^(-3) from probable human carcinogens including 1,3-butadiene and 1,2-dichloroethane. About 70% and 20% of total VOC cancer risk was due to the inhalation of 1,3-butadiene and 1,2-dichloroethane, respectively. Therefore, proper risk management of these 3 VOCs was required for the protection of health from cancer burden in Ulsan industrial complex area.

Ewald 합 기법을 이용한 구형 도파관의 H-면에 위치한 타원 편파 오프셋 십자 슬롯에 대한 해석

김병문,조영기,윤리호,손현 경북대학교 전자기술연구소 2000 電子技術硏究誌 Vol.21 No.1

This paper presents the analysis of an offset cross slot in the broad wall of a rectangular waveguide. The problem is formulated in teens of integro-differential equation which is solved using the method of moments with triangular Roop-top basis. For the effective numerical intgral evaluation, the Ewald sum technique is applied to the Green's function of the rectangular waveguide, transforming them into the rapidly convergent form. We have shown that a pair of narrow slots crossed at arbitrary angles and located at the proper point in the broad wall of an ordinary rectangular waveguide will radiate a wave very nearly circularly polarized at the desired direction.

혈액에서 혐기성 세균이 분리된 환자의 임상 및 세균학적 검토

정윤섭,이삼열,김진주 대한미생물학회 1985 大韓微生物學會誌 Vol.20 No.1

Isolation and identification of anaerabic bacteria fmm blood cultures are still technically demanding procedures. Recently, with thq use of gas hquid chmmatogWphy, the accuracy of identification is much improved, However, there has niver been a satisfactory data apalysis on anaerobic bacteremia in Korea. The authors evaluateid both the chnical and the bacteriological 4ata of 129 anaerobic bacteremias found at the Yonsei Medidal Center during the period of 1973 to 1984. The most frequently isolated anaerobic bacteria were Bacteroides (52.7%), among which the major spjcies was B. fragilis (38.7%) . Incidence of anae- robic bacterethia by sex was 57% in male and 43% in female. Mortality was high in groups below 1-year old and abom 50-year old. The cause of death seemed qlosely correlated with the patients age, general condition and the s!.verity of the underlying disease. Various neoplasms were the most common (20%) un- derlying disesses pxedisposing the anaerobic bacteremia. Biliary tract was considered the most frequent route of infection in anaetobic bacteremia. The frequent clinic8l signs in anaerobic bactetemia were fever (65%), followed by liver function abnormality (29%), jaundice (20%) and hypotention (18%) . When analysis of positive rate,of blood cutture was made on the patients from whom 4 cultures were done within 24 houm. It was found that 33% of the samples were positive. Isolation rate of anaembic bacteria in thioglycollate medium was 83.8%, while it was 44% in Tryptic soy broth. Among the anaerobic bacteremia, 25.4% were polymicrobia1 infections with aerobic bacteria (92.5%), such as E. Coli(33.3%). From these studies, it is con- cluded that h. fragilis is the most important causative organism in anaerobic bacteremia, with high fatality, particularly ih those who have underlying diseases. The ports of entry me mainly biliary, gastrointestinal and fernale genital traet. Fever is the most frequent clinical sign. Single blood culture is not sufficient to detect all anaerobic bacteremia, therefore more cultures with optimal time interval are needed. The incidence of polymicrohial infection in anaerobic bacteremia is higher than that in overall bacteremia.