• 한국결정성장학회지
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• 제13권2호
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• pp.88-92
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• 2003

본 연구에서는, Mn-Co-Ni 산화물계 NTC 써미스터의 열처리 조건에 따른 전기적 특성간의 상호관계에 대하여 고찰하였으며, 이를 위해 XRD. 소결체 밀도측정 및 B정수, 저항 열방산정수 등의 전기적 특성치를 조사하였다. NTC 써미스터의 열처리 과정은 Mn-Co-Ni 산화물 시험편의 소결특성에 큰 영향을 미치고있었으며, 본 연구의 조성하에서는 $1250^{\circ}C$, 2시간 동안 열처리한 경우 가장 높은 밀도치를 얻을 수 있었다. 이 조건하에서 미세구조 관찰결과 치밀화과정이 거의 완전하게 이뤄짐을 확인하였다. 제조된 NTC 써미스터는 소결 온도가 상승함에 따라 저항값 및 B 정수값이 커지는 것을 확인하였으며, 연료 액위의 변화에 다른 출력전압의 거동을 측정한 결과 선형 감소 거동을 나타내었다. 따라서, 본 연구에서 제조된 Mn-Co-Ni 산화물계 NTC 써미스터의 전기적 특성은 열처리 조건과 밀접한 연관성이 존재하는 것으로 사료되며, 향후 자동차용 연료액위센서로의 응용성이 가능할 것으로 기대된다.

• 문화기술의 융합
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• 제5권4호
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• pp.355-359
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• 2019

건성안 진단에 있어서 가장 많이 사용되는 방법 중 하나이나, 부정확한 결과로 신뢰도가 떨어지는 쉬르머 검사법을 대체할 수 있는 눈물양 측정 도구를 개발하고자 하였다. 이를 위해 다양한 흡수제에 대한 흡수성 시험을 통하여 알파 셀룰로즈 펄프를 흡수제로 선택하였다. 2차례에 걸쳐 시제품을 제작하여 평가하였으며, 최종적으로 알파 셀룰로즈 펄프를 폴리우레탄에 접착한 스트립 형태의 눈물양 측정 도구를 제작하여 사용성 평가를 실시하였다. 그 결과 해외에서 최근에 개발된 눈물양 측정 도구인 Strip Meniscometry와 유의한 상관성을 갖는 것을 확인할 수 있었으며, 측정시간 및 측정의 정확성 측면에서 쉬르머 검사법의 대체 검사법으로 유효한 것으로 판단되었다.

• 환경위생공학
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• 제8권1호
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• pp.29-47
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• 1993

The purpose of this study is to improve institution of EIA(Environmenta1 Impact Assessment) in Korea. For this study, institution of EIA in Korea and other countries and copies of EIS prepared in Korea were analyzed. As a result, improvements of EIA should require introducing EIA in projects and planning level, building environmental information system, estimating appropriate costs of EIS preparation.

• 기술사
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• 제29권5호
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• pp.99-103
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• 1996

In this paper we discuss Gigabit information communication service utilizing Gigabit information super-highway, multimedia data processing technology for the services, multimedia communication protocol for transmitting multimedia data and construction of Gigabit information communication network which can be accessed everywhere and present items which should be tactically prepared for high-level information society of the 21 st century.

• 한국지하수토양환경학회:학술대회논문집
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• 한국지하수토양환경학회 2000년도 추계학술대회
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• pp.23-30
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• 2000

A calculation technique which estimates natural recharge was proposed and prepared with the existing techniques. And the necessity to obtain representative averages of 'specific yield' was discussed.

• Biomolecules & Therapeutics
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• 제4권4호
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• pp.408-410
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• 1996

3, 4-Dihydro-3-oxo-2H-1, 2, 4-benzothiadiazine-1, 1-dioxides were synthesized as conformationally rigid analogues of sulfonylurea hypoglycemic agents. All the compounds prepared showed hyperglycemic activity. The hyperglycemic activity was enhanced for the diabetic rats in which the blood glucose level was increased by 30-70%.

• Journal of Nutrition and Health
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• 제28권9호
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• pp.825-833
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• 1995

This study was performed to investigate the influence of dietary fiber, which from whole food on the serum lipid level and bowel function in rats. The fiber sources of experimental diets were prepared by drying and milling of small water dropwort(WD), mugwort(MW), butterbur(BB) and apple(AP). Each fiber sources was mixed at the 15% level of the diet. The level of dietary fiber in WD, MW, BB diets was similar but that in AP diet was slightly low. Male rats of Sprague-Dawley strain were blocked into 5 groups ; WD, MW, BB, AP, FF(fiber free). The animals were fed ad libitum each of experimental diets for 37 days. Food intake of AP and FF groups were than other groups, FF group was lower than other grous in food efficiency ratio. MW group showed highest level in fecal weight and fecal water content and group has the longest transit time compare to other groups. Serum triglyceride level was not significantly different among groups. BB group showed the lowest level in the serum total cholesterol. WD and MW groups showed slightly higher level in the serum HDL cholesterol than other groups. Mucosa weight was not significantly different among groups. The activity of maltase in mucosa of small intestine was highest in FF groups. Absorption rates of calcium were not significantly different among groups. Absorption rate of magnesium was higher in FF group compare to others. And, absorption rates of phosphorus in MW and FF groups were slightly lower than other groups.

• Restorative Dentistry and Endodontics
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• 제19권1호
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• pp.85-96
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• 1994

In this study, 24 curved resin blocks were prepared by one of the following four methods: 1) Conventional technique using K-flexo files 2) Step-back technique using K-flexo files 3) Crown-down technique using K-flexo files 4) Canal Master instrumentation using Canal Master Resin blocks were sectioned, photographed, and evaluated the mean centering ratio and the mean area of dentin removed before and after the instrumentation. The results were as follows : I. the mean centering ratio 1. In the level 1 and level 3, there was no significant difference in the mean centering ratio. 2. In the level 2, Step-back technique showed the worst mean centering ratio among the tested groups(p<0.001) and there was no significant difference between the other three groups. 3. In the level 4, Canal Master instrumentation and Step-back technique showed better mean centering ratio than the other two techniques(p<0.001) and there was no significant difference between the two techniques. II. the mean area of dentin removed 1. In the level l and level 3, there was no significant difference in the mean area of dentin removed. 2. In the level 2, Canal Master instrumentation removed less dentin than the other three techniques(P<0.01). 3. In the level 4, Crown-down technique removed less dentin than the other three techniques(P<0.05).

• 한국철도학회:학술대회논문집
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• 한국철도학회 2004년도 춘계학술대회 논문집
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• pp.224-228
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• 2004

In these days, as it frequently happens that water level in the river exceeds the design floods due to irregular heavy rainfall, so it is required, first of an, to manage with railroad bridge safely. Because train control criterion under heavy rainfall is still not prepared and automatic flood monitoring system for railroad bridges is not used, worry over invisible economic loss due to train passage delay is in existence. Therefore, it is important to secure the safety and detect the risk like turnover or failure of railroad bridges through systematic disaster prevention system. And the transition from conventional monitoring method to real time monitoring method supported by sensors and communication system with high technology is rapidly needed. This research is on developing the real time flood monitoring system which prevents railroad disasters in advance by detecting continuously the water level of railroad bridge through CCD camera and water level gauge.

• 한국지하수토양환경학회지:지하수토양환경
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• 제6권1호
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• pp.33-43
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• 2001

본 연구에서는 지하수위 변동 곡선을 이용하여 지하수 함양률을 추정하는 기법을 제안하였으며 무강우 기간 지하수위 감수곡선을 이용한 기존의 방법과 비교하였다. 본 연구는 전국 지하수 함양률을 추정하기 위한 연구의 일환으로서 국가 지하수 관측망의 신뢰성 높은 지하수위 자료를 이용하였고 자료가 충실한 세 지역(충주, 진주, 광주)에 대하여 본 방법론을 적용하였다. 이를 위하여 각 지역의 지하수위에 대한 계절적 변동 분석, 지하 수위와 누적 강수량에 대한 시차분석, 지하수 함양률 비교 연구 분석 등을 실시하였다.