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적층판으로 보강된 철근콘크리트보에 대한 해석적 연구 (Analytical Study of Reinforced Concrete Beams Strengthened with Fiber Reinforced Plastic Laminates)

  • 채승훈;강주원
    • 한국공간정보시스템학회:학술대회논문집
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    • 한국공간정보시스템학회 2004년도 춘계 학술발표회 논문집 제1권1호(통권1호)
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    • pp.206-211
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    • 2004
  • This paper deals with the flexural strengthening of reinforced concrete beams by means of thin fiber reinforced plastic(FRP) laminas. This study focuses on modeling of structural of concrete bonded FRP laminate in flexural bending members. Used computational equation is derived by relation of stress and strain. The section analysis is based on experimental observations of a linear strain distribution in the cross section until failure, and a multi-linear moment-deflection curve that is divided into four regions, each terminated by a similarly numbered point. The load-deflection relationship in each region is assumed to be linear. The present model is validated to compare wit the experiment of 4-point bending tests of R/C rectangular beams strengthened with CFRP laminates, and has well predicted the moment-displacement relationships of members.

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추출방법에 따른 생강의 휘발성 성분 조성 비교 (Comparison of the Volatile Components of Korean Ginger (Zingiber officinal Roscoe) by Different Extraction Methods)

  • 이재곤;장희진;곽재진;이동욱
    • 한국식품영양학회지
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    • 제13권1호
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    • pp.66-70
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    • 2000
  • The volatile components of Korea ginger were compared by using different isolation methods, head-space sampling procedure(HSSP), simultaneous distillation extrction(SDE) and soild pahse micro-extractions(SPME). Sixty-one components were identified by GC-MSD in the extracts obtained from each extraction methods. However, the components identified showed a difference in their composition wit the extraction methods. In the extract by HSSP, fifty-five components including a high volatile compound such as acetaldehyde, ethylacetate, 2,3-butandione were detected, and thirty-one components were identified in the extract by SPME. While, the low volatile components such as elemol, zingiberenol and ${\beta}$-eudesmol were detected only in the extract by SDE method. The results suggest that SDE method is the best for the analysis of low volatile components, whereas HSSP is a proper method for the analysis of high volatile components from natural resources.

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광리소그래피에서 최적 모양의 패턴 구현을 위한 포토마스크 역설계 (Reverse design of photomask for optimum fiedelity in optical lithography)

  • 이재철;오명호;임성우
    • 전자공학회논문지D
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    • 제34D권12호
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    • pp.62-67
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    • 1997
  • The optical lithography wit an ArF excimer laser as a light source is expected to be used in the mass production of giga-bit DRAMs which require less than 0.2.mu.m minimum feature size. In this case, the distortion of a patterned image becomes very severe, since the lithography porcess is performed at the resolution limit. Traditionally, the photomask pattern was designed and revised with trial-and-error methods, such as repeated execution of process simulators or actual process experiments which require time and effort. Ths paper describes a program which automatically finds an optimal mask pattern. The program divides the mask plane into cells with same sizes, chooses a cell randomly, changes the transparent/opaque property of the cell, and eventually genrates a mask pattern which produces required image pattern. The program was applied to real DRAM cell patterns to produce mask patterns which genertes image patterns closer to object images than original mask patterns.

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가돌리니아 첨가 이산화우라늄의 점결함 모델에 의한 산소포텐샬 연구 (Defect Model for the Oxygen Potential of Urania doped wit Gadolinia)

  • Park, Kwang-Heon;Kim, Jang-Wook
    • Nuclear Engineering and Technology
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    • 제23권3호
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    • pp.321-327
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    • 1991
  • 가돌리니아 첨가 우라니아에 대한 점결함 모델이 순수 우라니아의 점결함구조를 바탕으로 하여 개발되었다. Gd 도펀트는 금속이온자리에 -1 유효전하를 지니고, 주위의 산소침입형을 밀어내어 산소침입형의 자리를 감소시킨다. 산소 공공 농도가 증가하면 Gd 도펀트는 산소공공과 집합체를 형성하게 된다. 이 점결함 모델은 Gd 도펀트의 양의 증가에 따른 산소포텐샬의 증가와 산소 대금추비율이 2일때 급속한 산소포텐샬 변화를 설명하여, 현존하는 실험값과 좋은 일치를 보였다.

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유공 보강 후판의 진동해석 (Vibration Analysis of Stiffened Opening Thick Plate)

  • 이효진;김일중;오숙경;정진택;이용수
    • 한국소음진동공학회:학술대회논문집
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    • 한국소음진동공학회 2004년도 춘계학술대회논문집
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    • pp.794-798
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    • 2004
  • This paper is analysis of stiffened opening thick plate on foundation. This paper has the object of investigating natural frequencies of opening thick plates on Pasternak foundation by means of finite element method and providing Kinematic design data for mat of building structures. In this paper, vibration analysis of rectangular opening thick plate is done by use of Serendipity finite element with 8 nodes by considering shearing strain of plate. And vibration analysis of stiffener is done by used of Timoshenko beam-column element wit 3 nodes. It is shown that natural frequencies depend on not only Winkler foundation parameter but also shear foundation parameter, opening position, opening size, stiffener size.

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國內 放送 衛星을 위한 오프셋 파라볼라 안테나의 設計에 關한 硏究 (A Study on the Design of an Offset Parabolic Antenna for the Domestic Broadcasting Satellite)

  • 최학근;박성룡;박정기
    • 대한전자공학회논문지
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    • 제26권2호
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    • pp.66-75
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    • 1989
  • 오프셋 파라볼라 안테나의 輻射特性을 빠른 시간에 判定할 수 있는 近似式을 제시하고 數値計算 結果와 比較함으로써 그 타당성을 입증하였다. 또한 本 論文에서 導出된 近似式을 사용하여 國內 地形 特性에 적합한 放逆衛星 搭載用 오프셋 파라볼라 안테나를 設計 製作하고 實驗했다. 實驗 結果는 비교적 設計 目標値에 근접하는 것으로 나타났다.

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LATTICE PATH COUNTING IN A BOUNDED PLANE

  • Park, H.G.;Yoon, D.S.;Park, S.H.
    • 대한수학회지
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    • 제34권1호
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    • pp.181-193
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    • 1997
  • The enumeration of various classes of paths in the real plane has an important implications in the area of combinatorics wit statistical applications. In 1887, D. Andre [3, pp. 21] first solved the famous ballot problem, formulated by Berttand [2], by using the well-known reflection principle which contributed tremendously to resolve the problems of enumeration of various classes of lattice paths in the plane. First, it is necessary to state the definition of NSEW-paths in the palne which will be employed throughout the paper. From [3, 10, 11], we can find results concerning many of the basics discussed in section 1 and 2.

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파코 라반 (Paco Rabanne) 작품에 표현된 다원주의 (Pluralism in Paco Rabanne′s Works)

  • 이봉덕;양숙희
    • 복식문화연구
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    • 제9권1호
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    • pp.141-153
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    • 2001
  • In the midst of rapid cultural and artistic changes with the turn of the century, postmodernism is exerting great influence on the value and trends of arts. many artists are making utmost efforts in order to overcome ambiguity and confusion caused by these changes. Analysis of the works and philosophy of prominent fashion designers provides insight into the influence of postmodernism to the creation of modern arts including fashion. This paper attempts to explore how pluralism, one o the most important features of postmodernism, has given impacted to the modern fashion design. fashion trend and works of Paco Rabanne were reviewed with particular emphasis on pluralistic expressions in his fashion creation. it was found that Paco Rabanne's diversified and innovative use of materials and design methods were possible due to the influence of pluralism. It is anticipated that this trend will e observed in the various forms of arts wit the further analysis of fashion designers and artists.

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SOI와 트랜치 구조를 이용한 초저소비전력형 미세발열체의 제작과 그 특성 (The Fabrication of Micro-heaters with Low Consumption Power Using SOI and Trench Structures and Its Characteristics)

  • 정귀상;홍석우;이원재;송재성
    • 한국전기전자재료학회논문지
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    • 제14권3호
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    • pp.228-233
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    • 2001
  • This paper presents the optimized design, fabrication and thermal characteristics of micro-heaters for thermal MEMS (micro elelctro mechanical system) applications usign SOI (Si-on-insulator) and trench structures. The micro-heater is based on a thermal measurement principle and contains for thermal isolation regions a 10㎛ thick Si membrane with oxide-filled trenches in the SOI membrane rim. The micro-heater was fabricated with Pt-RTD (resistance thermometer device) on the same substrate by suing MgO as medium layer. The thermal characteristics of the micro-heater wit the SOI membrane is 280$\^{C}$ at input power 0.9W; for the SOI membrane with 10 trenches, it is 580$\^{C}$ due to reduction of the external thermal loss. Therefore, the micro-heater with trenches in SOI membrane rim provides a powerful and versatile alternative technology for improving the performance of micro-thermal sensors and actuators.

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A STUDY ON SIMPLE TIME VARYING FEEDFORWARD COMPENSATOR

  • Kwon, Byung-Moon;Son, Won-Kee;Kwon, Oh-Kyu
    • 제어로봇시스템학회:학술대회논문집
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    • 제어로봇시스템학회 2000년도 제15차 학술회의논문집
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    • pp.500-500
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    • 2000
  • In this paper, we deal wit,11 a simple tim varying feedforward compensator in order to decrease the amount of undershoots and overshoots on the step response. This compensator makes the step type input be a ramp input with saturation for 0 $\leq$ t < $\alpha$. It will be shown that the system with the feedforward compensator has small amount of undershoot and overshoot at the price of rise time. Also, provided the system properly stable, the influence of the design parameter $\alpha$ on the step response of the system with the feedforward compensator is investigated in the current paper.

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