• 대한전기학회:학술대회논문집
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• 대한전기학회 1994년도 하계학술대회 논문집 C
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• pp.1599-1602
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• 1994

Recently, failure of COS(cut out switch) due to contamination has been increased. This paper is on the development of the contamination COS. 1 We designed a porcelain insulator of alternate shed for anti-contamination COS. 2 The COS was coated with HVIC(silicone) to improve resistivity to contamination. 3 The FOV characteristics of COS were examined to obtain dry FOV, wet FOV and contamination FOV.

• 미생물학회지
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• 제11권3호
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• pp.129-133
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• 1973

The authors have investigated about the microbial contamination of goods which is a criterion of hygienic control. Conducting on investigation, a special attention has been paid on the rate of microbial contamination in the goods, especially in manufacturing process of the softdrink. The authors also made an experiment on total microbes which is the criterion of contamination in each step of the process and in raw materials together with materials to be used for subdividing. Results obtained were as follows : 1) The orgin of microbial contamination was found in bottle cap and in tap water, that is, there appeared 9 colony per ml in bottle cap and 31-74 colony per ml in tap water, respectively. 2) It was found that microbial contamination are 4 colony per ml in average through year. However, it appeared 1 colony per ml in winter and 8 colony per ml in summer. 3) Coliform groups are not detected in goods through a year. 4) There was no variation in number of total microbes after ion exchange resin passage in purification process of tap water. 5) The number of microbes in goods are decreased when the raw materials are treated in high temperature short time (HTST) sterilization.

• 한국지반공학회논문집
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• 제24권5호
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• pp.15-25
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• 2008

본 논문에서 매년 항만개발 및 항로유지의 목적으로 발생하는 준설토사의 유효활용을 위하여 주요 항만 준설토사에 대하여 오염현황을 조사 및 분석하였다. 그리고 준설물질별 인간의 건강에 대한 피해확률을 과학적으로 추정하는 위해성 평가를 실시하여 공업 및 주거지역에서 직접 인체에 대하여 안전하고 유효하게 활용할 수 있는 기준을 제시하였다. 제시한 기준은 기존의 준설토사 처리.활용기준 및 토양환경보전법상의 환경기준보다 엄격한 것으로 나타났다. 그리고 유효활용에 대한 사전평가를 실시할 수 있는 관련 기준을 근거로 국내 주요항만의 발생준설토사에 대한 오염도를 평가한 결과, 일부 항만에서 카드뮴(Cd), 비소(As), 크롬(Cr) 및 아연(Zn)이 환경기준을 초과하는 것으로 나타나 정밀한 조사가 이루어져야 할 것으로 나타났지만 대부분 항만에서 발생한 준설토사는 유효활용이 가능한 것으로 나타났다.

• 한국정보디스플레이학회:학술대회논문집
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• 한국정보디스플레이학회 2009년도 9th International Meeting on Information Display
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• pp.1469-1471
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• 2009

Effect of contamination of liquid crystal on the electrical behavior of liquid crystal display (LCD) by spilled components from color filter layer was investigated. It is noted that the level of contamination was different following the kind of liquid crystal and organic layers. Transmittance curve of LCD cell was shifted by spilled components of color filter and BM materials. C-V curve also showed different behavior following color filter type. The results obtained show the image sticking of LCD can be varied by pairing liquid crystal with color filter materials.

• 한국식품영양과학회지
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• 제35권5호
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• pp.655-660
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• 2006

급식규모와 운영형태가 유사한 3곳의 급식소를 대상으로 원재료, 조리기구 및 조리종사원 손과 최종조리음식간의 미생물 오염실태를 분석한 결과는 다음과 같다. A 급식소에서는 닭볶음탕, 잡채, 비빔밥, 콩나물무침에서 황색포도상구균이 검출되었다. 닭볶음탕은 조리종사원의 손, 재료를 손질한 도마, 양파에서 황색포도상구균이 검출되었으므로 조리종사원의 손이나 도마를 통한 교차오염이 발생한 것으로 판단된다. 잡채는 조리종사원의 손, 당면을 삶아 건진 바구니, 양파와 양파를 손질한 도마에서 모두 황색포도상구균이 검출되었으므로 이들 간의 교차오염이 발생했을 것으로 생각된다. 비빔밥과 콩나물무침은 해당일 조리를 담당한 종사원의 손에서 황색포도상구균이 검출되었으므로 조리종사원 손에 의한 오염이 발생한 것으로 판단된다. B 급식소의 쥐어채조림은 원재료의 황색포도상구균이 조리과정에서 그대로 전이되어 조림 후에도 검출되었다. C급식소의 오징어채무침에서는 대장균이 검출되었다. 오징어채무침은 가열조리공정을 거치지 않는 메뉴로서 원재료인 오징어채에서 검출되었던 대장균이 그대로 최종조리 후까지 전이된 것으로 판단된다. 급식소 최종음식의 안전성 확보를 위해서는 위생적인 원재료의 구매와 사용, 조리종사원 개인위생의 개선, 조리기기의 철저한 세척 및 소독관리가 선행되어야 할 것으로 사료된다.

• 대한설비공학회:학술대회논문집
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• 대한설비공학회 2007년도 동계학술발표대회 논문집
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• pp.600-605
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• 2007

In this study, the risk rates of different contamination sources of the Foreign material in a minienvironment were analyzed through CFD simulation. From the results, the ambient contamination sources mainly affect wafers in the FOUP, whereas the internal contamination sources mainly affect wafers laid on the robot arm in the minienvironment. And the purging plenum system is very useful in protecting the wafers in the FOUP from Foreign materials transferred from the FFU. However, this system is unable to protect the wafers on the robot arm from internal Foreign materials and the wafers in the FOUP from sources of the interface between the FOUP and the minienvironment.

• 자원환경지질
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• 제30권4호
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• pp.371-377
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• 1997

This paper presents the geophysical applications to the environmenml problem in an abandoned mine area. We would like to focus our attention on the mapping of the soil contamination and the detection of the buried mine tailings. For mapping the soil contamination. measurements of both in-situ magnetic susceptibility (k) and terrain conductivity were carried out. In-situ magnetic susceptibilities of the contaminated soil due to the acid mine drainage show higher values than those of the uncontaminated area. However. those data do not show the correlation with the degree of the soil contamination observed on the surface. The least-squares fitted formula obtained with the measured insitu magnetic susceptibilities is $k=4.8207{\times}W^{0.6332}$, where W is the $Fe^{+2}$ weight percentage. This weight gives most effect to magnetic susceptibility of the soil. Lateral variations of the soil contamination in the shallow subsurface can be detected by the electrical conductivity distributions from EM induction survey. TDIP (Time Domain Induced Polarization) and EM induction surveys were conducted to detect the buried mine tailings. From the results of TDIP, the spatial zone, which shows high chargeability-low resistivity, is interpreted as the buried mine tailings. Therefore, it is concluded that it is possible to discriminate the spatial zone from the uncontaminated ground.

• 대한치과보철학회지
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• 제38권5호
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• pp.650-658
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• 2000

This study was investigated to compare the bond strength of polysulfide adhesive between tray resin and border molding materials and to evaluate the effect of saliva contamination on them. We made the 135 resin tray secimens with a dimension of $1{\times}1{\times}1cm$ and divided them into 3 groups by the materials 1) Quicky group, 2) Compound group, and 3) Impregum group Each group was subdivided by saliva contimination. Group S1 : applied adhesive without saliva contamination Group S2 : applied adhesive after drying 15seconds after saliva contamination Group S3 : applied adhesive no after saliva contamination. Tensile tests were performed with a Universal Load testing machine. Results showed Impregum group significantly higher bond strength than Quicky group, but there was no significant difference in adhesive bond strength between Compound group and Quicky group in experimental group by materials In experimental group by saliva contamination, S1 group is significantly higher bond strength than S2 group and S2 group is significantly higher bond strength than S3 group in Quicky group and S1, S2 group is significantly higher bond strength than S3 group in Compound group and Impregum group. Impression compound and Impregum F which are usually used as an individual tray border mold-ing material can be said to be satisfied in adhesive bond strength to polysulfide impression materials. After try-in and clinical adjustment are performed, a custom tray should be properly rinsed and air dried before tray adhesive was placed.

• 반도체디스플레이기술학회지
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• 제17권4호
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• pp.11-15
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• 2018

The parts of equipment for semiconductor are protected by anodic aluminum oxide film to prevent corrosion. This study investigated contamination particle and cracking behavior of anodic oxidation in sulfuric acid containing cerium salt. The insulating properties of the sample were evaluated by measuring the breakdown voltage. It was confirmed that the breakdown voltage was about 50% higher when the cerium salt was added, and that the breakdown voltage after the heat treatment was 55% and 35% higher at $300^{\circ}C$ and $400^{\circ}C$, respectively. After heating at $300^{\circ}C$ and $400^{\circ}C$, cracks were observed in non cerium and cerium 3mM, and more cracks occur at $400^{\circ}C$ than at $30^{\circ}C$. The amount of contamination particles generated in the plasma is about 45% less than that of non-cerium specimens.

• 한국재료학회지
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• 제9권5호
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• pp.491-495
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• 1999

In this study, we focus on Ca contaminant which affects on the roughness Si substrate after thermal process. The initial Si substrates were contaminated intentionally by using a standard Ca solution. The contamination levels of Ca impurity were measured by TXRF and the chemical composition of that was analyzed by AES. Then we gre the thermal oxide to investigate the effect of Ca contaminants. The microroughness of the Si surface, the thermal oxide surface, and the surface after removing the thermal oxide were measured to examine the electrical characteristics. The initial substrates that were contaminated with the standard solution of Ca exhibited the contamination levels of 10\ulcorner~10\ulcorneratoms/$\textrm{cm}^2$ which was measured by TXRF. The Ca contaminants were detected by AES and exhibited the peaks of Ca, SI, C and O.After intentional contamination, the surface microroughness of this initial substrate was increased from $1.5\AA$ to 4$\AA$ as contamination levels became higher. The microroughness of the thermal oxide surfaces of both contaminated and bare Si substrates exhibits similar values. But the microroughness of the contaminated$ Si/SiO_2$ interface was increased as contamination increased. The thermal oxide of contaminated substrate exhibited the small minority carrier diffusion length, low breakdown voltage, and slightly high leakage current.