• 제목/요약/키워드: 성병

검색결과 407건 처리시간 0.025초

소결 금속 윅 히트파이프 개발을 위한 제조 기술 연구 (A Study on the Manufacturing Technology for the Development of Heat Pipes with a Sintered Metal Wick)

  • 최지훈;김성대;성병호;유성열;박형기;김철주;고한서
    • 유체기계공업학회:학술대회논문집
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    • 유체기계공업학회 2006년 제4회 한국유체공학학술대회 논문집
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    • pp.479-482
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    • 2006
  • The most the electronic industry has recently accelerated the modularization, the miniaturization and the high integrated trend of electronics fields such as electronics components, appliances and etc., the most increasingly the heat generation problem rises. Even though the conventional cooling technologies are widely used in order to reduce the heat loads, the technologies are not easy to meet the present trends due to the fact that most of many conventional methods are relative to external form environments such as size, design and so on. With regardless of those environments, however, a heat pipe is one of the most efficient systems to improve the heat transfer performance. And then the performance of the heat pipe depends on a wick structure. Of various wick structures, sintered metal wick is known so that it has some advantages such as smaller pore size, increasing porosity as well as high reliability. In this study sintered metal wicks, thickness 0.7 mm, 0.8 mm and 0.9 mm, were manufactured as of $100{\mu}m$ copper powder to obtain the manufacturing technology of heat pipes mounted with a sintered metal wick. Furthermore, experiments for the operational performance factors such as capillary limit, thermal resistance were not only performed but also compared with a theoretical model simultaneously. Experimental results agreed with the theoretical model, and then it seems to be required to study various development processes of sintered metal wicks for the high performance of a heat pipe system.

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사과나무 부난성 병해(부난병, 동고병, 동부병)에 관한 연구 제1보 발생상황 (Studies on the Canker of Apple Tree Caused by Valsa mali $M_{IYABE}$ et $Y_{AMADA}$ (I. Occurrence))

  • 김승철;원창남;이응권;손준수;한의동
    • 한국응용곤충학회지
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    • 제9권2호
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    • pp.81-84
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    • 1970
  • 1) 본 보고는 사과나무 부란성병의 발생상황에 대하여 주산지인 충북, 충남, 경북등 3개도에서 1967년부터 1970년까지 4년 간 조사한 것이다. 2) 피해상황은 각지방에서 $30\%$ 내외가 감염되어 사과재배에 큰 위협을 주고 있다. 3) 수령별로는 대체로 수령이 많아질 수록 발병이 심한 펀이었다. 4) 품종간에는 홍옥의$6.1\%$가 가장 발병이 많았고 그 외는 Golden Delicious, 인도, 국광, 축의 순위였다. 5) 시비관계는 질소다량시비구가 $21.9\%$로 소양시비구에 비하여 약 1/3정도 발병이 많았으며, 붕소를 사용한 과원은 대조과원보다 약 1/4-1/6 정도로 발병률이 감소되었다. 6) 재배지대별로 보면 충북에서는 하천지대에 발병이 심했으나 경북지방은 대체로 하천, 평야, 구릉지대 어디서나 비슷한 경향이었다.

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저가형 열영상 시스템을 위한 실리콘 윈도우 제작 (Fabrication of Silicon Window for Low-price Thermal Imaging System)

  • 성병목;정동건;방순재;백선민;공성호
    • 센서학회지
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    • 제24권4호
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    • pp.264-269
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    • 2015
  • An infrared (IR) bolometer measures the change of resistance by absorbing incident IR radiation and generates a signal as a function of the radiation intensity. Since a bolometer requires temperature stabilization and light filtering except for the infrared rays, it is essential for the device to be packaged meeting conditions that above mentioned. Minimization of heat loss is needed in order to stabilize temperature of bolometer. Heat loss by conduction or convection requires a medium, so the heat loss will be minimized if the medium is a vacuum. Therefore, vacuum packaging for bolometer is necessary. Another important element in bolometer packaging is germanium (Ge) window, which transmits IR radiation to heat the bolometer. To ensure a complete transmittance of IR light, anti-reflection (AR) coatings are deposited on both sides of the window. Although the transmittance of Ge window is high for IR rays, it is difficult to use frequently in low-price IR bolometer because of its high price. In this paper, we fabricated IR window by utilizing silicon (Si) substrate instead of Ge in order to reduce the cost of bolometer packaging. To enhance the IR transmittance through Si substrate, it is textured using Reactive Ion Etching (RIE). The texturing process of Si substrate is performed along with the change of experimental conditions such as gas ratio, pressure, etching time and RF power.

P-224 ECC와 2048-비트 RSA를 지원하는 공개키 암호 프로세서 (A Public-key Cryptography Processor supporting P-224 ECC and 2048-bit RSA)

  • 성병윤;이상현;신경욱
    • 전기전자학회논문지
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    • 제22권3호
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    • pp.522-531
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    • 2018
  • FIPS 186-2에 정의된 224-비트 소수체 타원곡선 암호와 2048-비트 키길이의 RSA 암호를 단일 하드웨어로 통합 구현한 공개키 암호 프로세서 EC-RSA를 설계하였다. ECC의 스칼라 곱셈과 RSA의 멱승 연산에 공통으로 사용되는 유한체 연산장치를 32 비트 데이터 패스로 구현하였으며, 이들 연산장치와 내부 메모리를 ECC와 RSA 연산에서 효율적으로 공유함으로써 경량화된 하드웨어로 구현하였다. EC-RSA 프로세서를 FPGA에 구현하여 하드웨어 동작을 검증하였으며, 180-nm CMOS 셀 라이브러리로 합성한 결과 11,779 GEs와 14 kbit의 RAM으로 구현되었고, 최대 동작 주파수는 133 MHz로 평가되었다. ECC의 스칼라 곱셈 연산에 867,746 클록 사이클을 소요되어 34.3 kbps의 처리율을 가지며, RSA의 복호화 연산에 26,149,013 클록 사이클이 소요되어 10.4 kbps의 처리율을 갖는 것으로 평가되었다.

천화분 메탄올 추출물의 멜라닌 형성 억제 효과 (Inhibitory Effect of Methanolic Extract from Radix Trichosanthis on Melanin Synthesis)

  • 김정근;김남권;임규상;김진;성병곤
    • 대한한의학회지
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    • 제23권4호
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    • pp.45-54
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    • 2002
  • Objectives: In order to investigate the relationship of Radix Trichosanthis components and the melanin synthesis, the author has analyzed the cell viability and tyrosinase activity, melanin content and morphologic changes in n-hexane, EtOAc, n-BuOH, and H2O fraction. Methods: At first, in order to determine the concentration of the Radix Trichosanthis component, the author investigated the viability of B16 melanoma cell. To measure the effects of Trichosanthes kirilowii extracts (n-BuOH, n-Hexane, EtOAc, H2O fractions) on the viability of A549 cells, A549 cells were treated with various concentrations (from 0.5 to $25{\;}\mu\textrm{g}/ml$) of components of Trichosanthes kirilowii. After 24hrs, the cell viability was measured by MTT assay. The EtOAc components of Trichosanthes kirilowii decreased the viability of A549 cells in a dose-dependent manner. H2O and n-BuOH components had no cell toxicity till $25{\;}\mu\textrm{g}/ml$, the n-hexane component showed minor cell toxicity at $25{\;}\mu\textrm{g}/ml$ and the EtOAc component cell toxicity was revealed at $5{\;}\mu\textrm{g}/ml$ concentration. Results: 1. The results of tyrosinase activity and the Radix Trichosanthis component; n-hexane and EtOAc components controlled it effectively; the n-BuOH components were less effective. 2. The results of melanin content analysis showed that the n-hexane and EtOAc components effectively inhibited, the n-BuOH fraction inhibited less, and H2O component didn't inhibit the terminal melanin formation. 3. In the n-BuOH and H2O component there were no changes, but in the n-hexane component the melanin content was effectively inhibited. 4. In the EtOAc fraction, although the melanin content was inhibited, the cell count was evidently suppressed, Of all of the Radix Trichosanthis components, the n-Hexane and EtOAc fractions inhibited the melanin synthesis best, but owing to its toxicity, the EtOAc components inhibited the cell count. Conclusion: The above results demonstrated that Radix Trichosanthis n-hexane fraction efficiently inhibited the tyrosinase activity and melanin synthesis.

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실험적 간 발암모델에서 감마선 조사 돼지고기 섭취가 전암성병변의 생성, 약물대사 효소계 및 소포체 막 안정성에 미치는 영향 (Effects of $\Upsilon$-Irradiated Pork Feeding on Preneoplastic Hepatic Lesion, Cytochrome P450 System and Microsome Glucose 6-Phosphatase Activity in Rat Hepatocarcinogenesis)

  • 김미정;김정희
    • Journal of Nutrition and Health
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    • 제35권6호
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    • pp.643-649
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    • 2002
  • This study was done to investigate effects of ${\gamma}$-irradiated pork feeding on the formation of glutathione S-transferase placental form positive (GST-P$^{+}$) foci, lipid peroxidation, cytochrome P450 system and microsomal glucose 6-phosphatase activity in diethylnitrosamine (DEN)-initiated rat hepatocarcinogenesis. Weaning Sprague-Dawley male rats were fed the diet containing ${\gamma}$-irradiated ground pork at the dose of 0, 3, 10, 30 kGy as a 20% of protein source for 8 weeks. One week after feeding, rats were intraperitoneally injected twice with a dose of DEN (50 mg/kg BW). As a promote.,0.05%phenobarbital was fed in drinking water from one week after DEN treatment until the end of experiment. At the end of 8th week, rats were sacrificed and hepatic GST-P$^{+}$ foci, microsomal malondialdehyde (MDA) and conjugated diene contents were determined. In addition, cytochrome P450 content and the activities of NADPH cytochrome P450 reductase and glucose 6-phosphatase were also measured. There was no significant effect by gamma irradiation on microsomal MDA content, conjugated diene, cytochrome P450 content and activities of NADPH cytochrome P450 reductase and glucose 6-phosphatase. However with DEN treatment, microsomal MDA content showed a increasing tendency. Cytochrome P450 content was also significantly increased while microsomal glucose 6-phophatase activity was significantly decreased with DEN treatment. However the activity of NADPH cytochrome P450 reductase was not affected. An interesting finding in this study was that the number and area of hepatic GST-P$^{+}$ foci of rats fed gamma irradiated pork were tended to be decreased by high dose of irradiation, but were not significantly different. These results might imply that the consumption of low dose of gamma irradiated pork does not affect the formation of hepatic GST-P$^{+}$ foci and lipid peroxide and membrane stability.ability.

용융 아연과 WC-Co 코팅층 내 코발트의 반응거동에 미치는 아연욕 중의 Al 첨가 영향 (Effect of Al Addition on the Reaction Behavior of Pure Cobalt with Molten Zinc)

  • 성병근;김규영;권성희;이기안
    • 한국표면공학회지
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    • 제40권1호
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    • pp.23-31
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    • 2007
  • The objective of this study is to investigate the effect of Al addition on the reaction behavior of cobalt with molten zinc. Pure cobalt specimen was immersion tested in the three kinds of molten zinc (pure, 0.12%Al added and 0.24%Al added) baths at $460^{\circ}C,\;490^{\circ}C\;and\;520^{\circ}C$. For the understanding of degradation processes, specimens were analyzed with scanning electron microscope (SEM) and energy dispersive spectrum (EDS), and electrochemical stripping method. When 0.12% and 0.24% Al was added in molten zinc baths, three intermetallic compounds layers of ${\gamma},\;{\gamma}_1,\;and\;{\gamma}_2$ were formed on the Co matrix and ${\beta}_1$ layer was not formed between the Co matrix and the ${\gamma}$ layer. Particles of CoAl intermetallic compound were formed at the interface between the ${\gamma}_2$ layer and zinc melt and they did not adhere to the Co-Zn intermetallic layer. Weight loss of the Co specimen increased as Al content in the molten zinc increased and the relationship of weight loss vs. immersion time followed parabolic rate law. Rate controlling process for the reaction rate of Co with Al added molten zinc was analyzed as the diffusion process of Al atom through a boundary layer between the ${\gamma}_2$ layer and the Al added zinc melt.

거골 경부 골절의 합병증 (The Complication of the Talar Neck Fracture)

  • 성병년;박완수;이승기;박찬지;김동원
    • 대한족부족관절학회지
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    • 제7권1호
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    • pp.119-125
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    • 2003
  • Purpose: The purpose of this study fracture. Materials and Methods: The clinical and radiological analysis were performed on 19 cases of the talus neck fractures who had been treated with conservative treatment or variable methods of operative treatment. Each cases followed up more than 1 year and 6 months from May 1989 to June 2001. The clinical results were analyzed according to the age, cause of injury, fracture type of Hawkins classification, associated soft tissue injury, method of treatments, complications, and Hawkins scoring system. Results: According to Hawkins classification, type I was 6 cases(32%), type II was 5 cases(26%), typeIII was 7 cases(37%), and typeIV was 1 case(5%). In all cases, complete bony union was obtained. According to the Hawkins scoring system, 8 cases(42%) were excellent and good. Avascular necrosis was 4 cases(25%). Traumatic arthritis was 10 cases which were occurred in type II, III and IV. An ankle fusion was 1 case. Conclusion: In talar neck fractures, non-displaced fracture treated by the cast immobilization and displaced fracture treated by early open reduction and internal fixation were expected good results. The complications were 77% of traumatic arthritis and 31% of avascular necrosis in type II, III and IV. We should preoperatively explain to the patient for high complication rates of traumatic osteoarthritis and avascular necrosis in the talus neck fractures.

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다중 결합 예측 알고리즘을 이용한 교통사고 발생건수 예측 (Multiple aggregation prediction algorithm applied to traffic accident counts)

  • 배두람;성병찬
    • 응용통계연구
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    • 제32권6호
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    • pp.851-865
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    • 2019
  • 하나의 시계열 자료에서 다양한 특징을 발견하는 일은 간단한 문제가 아니다. 본 논문에서는 하나의 시계열 자료에서 복수의 패턴을 찾아내어 예측 정확도를 높이는 방식인 다중 결합 예측 알고리즘을 소개한다. 이 알고리즘은 시간적 결합과 예측값 조합의 개념을 사용한다. 시간적 결합 방식을 통해, 하나의 시계열 자료에서 여러 개의 시계열 자료를 생성할 수 있으며, 각각의 자료는 별도의 특성을 가지게 된다. 여러 개의 시계열 자료에서 다양한 특성을 추출하기 위하여 지수평활법을 사용하고 시계열 요소들 및 이들의 예측값을 계산한다. 마지막 단계에서 시계열 요소 별로 예측값을 혼합 한 후, 각 시계열 요소들의 조합값을 더하여 최종 예측값을 만든다. 실증 분석으로 국내 교통사고 발생 건수를 예측한다. 분석 결과, 기존의 다른 예측 방식보다 예측 성능이 우수함을 확인할 수 있다.

잔디 토양전염성병원진균에 대한 길항미생물의 분리 및 길항효과 (Isolation of Antibiotic-producing Microorganisms Antagonistic to Soilborne Pathogenic Fungi of Bentgrass and Their Antifungal Activity)

  • 이용세;전하준;이창호;송치현
    • 한국유기농업학회지
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    • 제6권1호
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    • pp.133-149
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    • 1997
  • Recently, the importance of management and cultivation of grasses has been increased in Korea. Among these cultural practices, the appropriate control of diseases is considered more important than other cultivation techniques such as fertilization and irrigation. The damages of brown patch and large patch caused by Rhizoctonia spp. and Pythium blight caused by Pythium spp. are serious in the major cultivation area of turfgrass in Korea. Since these diseases are difficult to control by agrochemicals, the damages are very serious if these are occured. The periodic spray of agrochemicals, to protect and control these diseases could make some problems of toxicity and environmental pollution as well as rising of non-target diseases. Therefore, the biological methods to control diseases have been required to decrease problems resulted from overuse of agrochemicals, to conserve natural ecosystem, and to control effectively diseases of grasses in the long period. The number of studies about biological control using antagonistic microorganisms have been increased for last half century. However, the application of biological control method has been very limited. In this study, thirteen isolates of R. cerealis, 8 isolates of R. solani and 3 isolates of Phthyn spp. have been isolated from diseased turfgrass in golf course and grass-culture area that have patch and wilting symptoms of zoysia grass and creeping bentgrass. Isolation frequency of R. cerealis and R. solani was high in especially zoysiagrass, while Pythym spp. was isolated from bent grass at low frequency but showed high pathogenicity. Totally, 205 isolates of soil microorganisms were isolated in this study as primary antagonistic microorganism by Herr's triple agar layer plate and dual culture method using rhizosphere of grasses, soil of crop field as the source of antagonistic microorganisms. Among the 205 isolates, 23 isolates were actinomycetes and 182 isolates were bacteria. All of the actinomycetes were isolated by Herr's method. Antagonistic effect of primary isolated microorganisms was tested for in vitro mycelial growth inhibition against pathogenic fungi isolated from grasses and for inhibition of disease occurrence in 24 well tissue culture plate and pot experiment. Then, four isolated of bacteria which are BG23, BG74, BG136 and BG171 were selected as antagonistic microorganisms against soil-born pathogenic fungi of bentgrass.

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