• 제목/요약/키워드: inpact

검색결과 7건 처리시간 0.012초

코팅부 균열의 충격특성 해석 (An Analysis on the Impact Characteristics in a Layered Half-Space with a Cathing Region)

  • 이강요;권순만
    • 한국정밀공학회:학술대회논문집
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    • 한국정밀공학회 1995년도 추계학술대회 논문집
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    • pp.664-667
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    • 1995
  • The purpose of this paper is to consider the disk failure phenomenon based on the second kind Fredholm integral equation and numerical inversion of Laplace transform when the head hit disk asperities at HDI under antiplane impact loading. The model for analysis is a two layeered half-space with a circumferential surface edge crack. The optimum design parameters to reduce the disk failure due to impact are presented

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산성비가 토양미생물에 미치는 영향 (Effect of Acid Rain in Soil Microorganism)

  • 김갑정;임진아;박성주;문형태;박경량;이인수
    • 생명과학회지
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    • 제8권3호
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    • pp.299-304
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    • 1998
  • In order to clarify the effects of acid rain on soil microorganisms, the inpact of acid to soil microorganisms was survyed for 14 weeks using soil microcosms from industrial site A and B, Gaejok mountain, and Daechong lake in Taejeon area. The acid tolerant-microorganisms in natural soil, using culturing method were counted to be 5.8 - $8.0{\times}10^6$CFU/g soil. The number of microorganisms using ATP-biomass analysis for natural soil samples were also analyzed and 2.2 - $2.6{\times}10^9$ cell/g soil in industrial site A and B, Gaejok mountain, and Daechong lake were determined. In soil samples, which were treated with artificial acid rain, the number of acid tolerant microorganisms were counted 2.9 - $5.8{\times}10^5$ and 2.8 - $7.5{\times}10^8$, respectively. Therefore, we conformed that the numver of soil microorganisms were influenced by acid rain. Also, long term acid tolerant microorganisms were identified as Rhodotorula sp. and Pseudomonas sp.

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송전비용 산정방법이 Genco에 미치는 영향 평가 (Analysis on effect of Transmission Pricing to Gencos)

  • 김강원;정구형;한석만;김발호
    • 대한전기학회:학술대회논문집
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    • 대한전기학회 2004년도 하계학술대회 논문집 A
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    • pp.689-691
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    • 2004
  • Transmission Pricing is the factor of giving locational signal when Genco decides the generation expansion schedule. Therefore, TR-Pricing is influenced to generation expansion schedule. TR-Pricing is composed of three element, loss-cost and congestion-cost and equipment-cost. The main target of this paper is to analyze TR-Pricing's(especially loss-cost) inpact to generation expansion schedule. Then, this paper make a optimal counterproposal to decide the generation expansion schedule.

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신.재생에너지발전 의무비율 할당제(RPS) 도입 국제비교 연구 (A Study on Introducing Renewable Portfolio Standard(RPS) in Korea)

  • 부경진;허은녕;;조상민
    • 신재생에너지
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    • 제1권3호
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    • pp.14-23
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    • 2005
  • Korean government set the goal of 5.6% to use renewable energy in electricity generation by 2011 compared with the current use of 0.13%. To achieve this goal, an innovative plan for market competitiveness would be required in addition to the feed-in-tariff [FIT] which is carried out at present in Korea. As a countermeasure, Ministry of Commerce, Industry and Energy [MOCIE] has taken it into consideration to introduce a Renewable Portfolio Standard [RPS] that is a purchase obligation program as an alternative plan to the FIT. Furthermore, the active renewable energy market may result from and also reversely result in the aid of North Korea with renewable energy. In this paper, we review The RPS in several country cases. Plans, systems, markets and institutionalization for solving efficiency in the area of renewable energy are discussed.

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횡방향 하중을 받는 CFRF 적층복합재의 내부손상에 관한 연구 (A Study on the Damage of CFRP Laminated Composites Under Out-of-Plane Load)

  • 김문생;박승범;오득창
    • 한국정밀공학회지
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    • 제12권11호
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    • pp.98-109
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    • 1995
  • An investigation was performed to study the inner damage of laminated composite plates subjected to out-of-plane load. During the investigation, inpact velocity and equivalent static load relationship was derived. Reddy's higher-order shear deformation theory(HSDT) and Hashin's failure criteria were used to determine inner stresses and damaged area. And impact testing was carried out on laminated composite plates by air gun type impact testing machine. The CFRP specimens were composed of [ .+-. 45 .deg. ]$_{4}$and [ .+-. 45 .deg. /0 .deg. /90 .deg. ]$_{2}$ stacking sequences with 0.75$^{t}$ * 26$^{w}$ * 100$^{l}$ (mm) dimension. After impact testing. As a result, a relationship holds between damaged area and impact energy, and a matrix cracking was caused by the interlaminar shear stress in the middle ply and was caused by the inplane transverse stress in the bottom ply.

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하수관로 배면 공동 탐지를 위한 최적 물리탐사 방법 (Optimal Geophysical Exploration Performance Method for Common Detection Behind a Sewer)

  • 김진영
    • 한국지반환경공학회 논문집
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    • 제19권8호
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    • pp.11-17
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    • 2018
  • 최근 도심지를 중심으로 도로함몰이 증가하고 있어 시민들의 안전을 위협하고 있다. 도로 하부에는 상하수도관로, 전기통신시설 등 각종 도로시설물이 매설되어 있는데 이 시설물의 노후화가 도로 함몰의 원인으로 작용하고 있다. 특히, 도로함몰의 주된 원인으로 주목받고 있는 노후 하수관의 경우 CCTV 탐사를 통해 간접적인 방법으로 지반함몰 위험도를 산정하고 있다. 현재 GPR 탐사를 통해 공동을 탐사하고 있지만 지표면에서 탐사하기 때문에 관로 배면에 있는 공동을 찾기 어렵다. 따라서 본 연구에서는 비파괴 공동 탐사 기법에 대해 조사하고, 조사 기술 중 하수 관로 내부에서 관로배면에 존재하는 공동을 탐사할 수 있는 최적 기술 선정하고 각 기술별로 테스트 베드에서 검증했다. 이는 하수관 주변 공동을 확인하기 위한 객관적이고 정량적인 평가 방법으로 판단된다.