• Title/Summary/Keyword: 강선

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Technical Trends of Launch Complex of Neighboring Countries of Korean Peninsula - Russia and China (한반도 주변국의 우주발사체 발사대 현황 소개 - 러시아 및 중국 사례)

  • Kang, Sunil
    • Proceedings of the Korean Society of Propulsion Engineers Conference
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    • 2017.05a
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    • pp.41-46
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    • 2017
  • The three neighbors of Korean peninsula, Japan, China, Russia are leading countries of the world as national power and economic power. They are also leading the field of science, particularly top class in the space development. In comparison, our country, Korea, has been going on develop new launch vehicle and building new launch complex in accordance with national space program. In this paper, examining the technical trends of launch complex of Russia and China which based on Russian rocket technologies and it will make a reference for KSLV-II and future space program through this information.

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Night-Time Pedestrian Detection Techniques by Using Thermal Images (적외선 이미지 기반 야간 보행자 인식)

  • Lee, Jongkyu;Kang, Sun;Piao, Jingchun;Shin, Hyunchul
    • Proceedings of the Korean Society of Computer Information Conference
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    • 2012.07a
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    • pp.83-86
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    • 2012
  • 본 논문에서는 야간에 보행자인식의 성능 향상을 위한 효율적인 인식 방법을 제안한다. 이 논문은 야간에 차량에 비치 된 Thermal Camera를 이용하여 적외선 영상을 얻은 후, 적응적 thresholding, Histogram Equalization, Morphology Operation, Labelling, HOG및 SVM Training 방법을 사용하여 보행자의 인식율을 높이도록 하였다. 3830개의 training 영상을 사용하였으며 실험결과 우수한 인식 결과를 얻었다.

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Analytical Model for Transfer Bond Performance of Prestressing Strands (PS 강선의 정착부착성능에 관한 해석 모델)

  • 유승룡
    • Magazine of the Korea Concrete Institute
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    • v.6 no.4
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    • pp.92-101
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    • 1994
  • A new analytical model is proposed to better understand the transfer bond performance in a prestressed pretensioned concrete beam. The transfer length is divided into an elastic and a plas tic zones in this model. The bond stress is assumed t.o increase proportionally with the slip t.o the lirnit of maximum bond stress within the elastic zone and remains at a constant maximum value wthin the plastic zone. Four main stress patterns: bond stress, slip, steel stress, and concrete stress distributions within the transfer length are obtained precisely. The total transfer length al\ulcornerd free-end slip obtained here give a close comparison to the test results by Cousins et al.

Development of the Prefabricated Anchoring Device for External Strengthening (외부 강선 보강용 조립식 정착장치 개발 연구)

  • Han Man-Yop;Lee Sang-Wook
    • Proceedings of the Korea Concrete Institute Conference
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    • 2004.11a
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    • pp.461-464
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    • 2004
  • External prestressing method is the most papular method to strengthen concrete structures. The key parts of external prestressing method is an anchoring device which holds the prestressing cables. The most popular anchoring devices is an end bearing type, which has to be welded at site to assamble the anchor. The welding at site has a significant Quality problem. In this paper, new anchoring system has been developed, which needs no site welding. A design method for the new anchor has been proposed and developed to optimize the anchoring system. The developed anchors are very efficient, small, and compact, which have two types, one for abutment section and the other one for pier section. The anchors are expected to be used very widely, because of its convinience.

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An Experimental study of External Prestress Strengthening Method for continuous bridges (외부강선을 이용한 연속교 보강공법의 실험적 연구)

  • Han, Man-Yup;Shin, Jae-Woo;Kang, Tae-Heon;Jin, Kyung-Suk;Kang, Sang-Hun
    • Proceedings of the Korea Concrete Institute Conference
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    • 2006.11a
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    • pp.117-120
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    • 2006
  • This study is for the strengthening method of continuous bridge through external tendon strengthening that is the most general and effective among concrete bridge's strengthening method. Recently, it is numerous that slab's parts between spans have continuity for improving trafficable ability. However, in this case, slab would have a crack; bridge's durability would be damaged, and also it is too difficult to manage and maintain bridge due to the tensile strength of negative moment. Therefore, the purpose of this study is to demonstrate load-carrying through experiments and develop new external pre-stressing strengthening method for reinforcing continuous bridge.

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Behavior of Multiple Vinyl House Frames Reinforced by Steel Wire (강선으로 보강된 연동형 비닐하우스 골조의 구조거동)

  • Jung, Dong Jo;Kim, Jin;Seo, Yun Soo
    • Journal of the Korean Institute of Rural Architecture
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    • v.18 no.3
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    • pp.35-42
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    • 2016
  • For the reason of economy, farmers and structural engineers prefer the vinyl house frame members that have the lightest cross sections. Therefore, in order to reach this aim, rod bracing system is the best method for multiple vinyl house frames. In this study, wire rods (tension members) are used to be bracing members in multiple vinyl house frames. The effects of additional wire rods in the frames are investigated by the variations of the bending moments, axial forces, displacements and combined stresses in the main frames that are reinforced by different shapes of rod bracing system. Vinyl house frames are usually made by steel pipe members and collapsed by the excessive wind and snow loads. Two kinds of bracing models are used for wind and snow loads separately in this study. The effective bracing models for each load are finally figured out.

The Development of ACNR Conductor( I ) - Mechanical Properties (ACNR가공송전선의 개발( I ) - 기계적 특성)

  • Kim, Shang-Shu;Kim, Byung-Geol;Lee, Hee-Woong;Park, Joo-Hwan
    • Proceedings of the Korean Institute of Electrical and Electronic Material Engineers Conference
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    • 2005.07a
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    • pp.635-636
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    • 2005
  • 최근에 미국이나 러시아를 중심으로 가공승전선의 승전효율을 증대시키고자 하는 연구가 활발히 이루어지고 있으며 어느 정도 성과를 거두고 있다. ACSR가공송전선에서 교류전류의 흐름에 의하여 코어 (Core)에 자기장이 발생되어 투자율이 증가되고 이로 인하여 알루미늄층에서 전류밀도의 재 분포, skin effect 등으로 인하여 전력손실이 발생된다. 본 연구에서는 기존의 ACSR가공송전선의 코어 (Core)인 고탄소강선 대신에 비자성이면서 고강도인 새로운 강선을 코어재료로 채택한 ACNR(Aluminum Conductor Nonmagnetic Steel Reinforced)가공송전선을 개발하여 전력손실을 감소시켰다.

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Effect of Kimchi ingredients on the growth of pathogenic and lactic acid bacteria (김치부재료의 유산균 증식 및 유해균 억제효과)

  • Kang, Sun-Yi;Han, Myung-Joo
    • Korean journal of food and cookery science
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    • v.21 no.6 s.90
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    • pp.838-843
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    • 2005
  • When ingredients of Kimchi were mixed and stored in $18^{\circ}C$, lactic acid bacteria, such as Leuconostoc mesenteroides and Lactobacillus plantarum, were selectively grown up. Herefore, to understand why lactic acid bacteria were selectively cultured in Kimchi, antibacterial activities of Kimchi ingredients against some pathogens and Kinlchi lactic acid bacteria were investigated. Kimchi mixed with all ingredients significantly inhibited the growth of all tested pathogens: S. typhimurium, S. sonnei, and E. coli. Kimchi without green onion, garlic or ginger inhibited the growth of S. typhimurium, but did not E. coli and S. sonnei. However, Kimchi without red pepper powder did not inhibit the growth of all tested pathogens. All ingredients of Kimchi did not inhibit the growth of L. plantarum and L. mesenteroides. These results suggest that Kimchi ingredients can synergistically inhibit the growth of pathogens and Kimchi may be a selective medium for lactic acid bacteria.

Basic Design of fire protection system for Naro Space Center (나로우주센터 발사대 소화설비 기본 설계)

  • Kim, Sang-Heon;Yoon, Suk-Hwan;Bershadskiy, V.A.;Jung, Young-Suk;Kang, Sun-Il;Oh, Seung-Hyub
    • Proceedings of the Korea Institute of Fire Science and Engineering Conference
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    • 2010.10a
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    • pp.199-202
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    • 2010
  • 우주발사체를 운용하는 발사장은 화재나 폭발의 위험에 많이 노출 되어 있다. 발사장은 비행시험전 발사체의 모든 상태를 점검 하고, 비행시험을 수행하는 곳이다. 또, 유사시에는 대량의 산화제와 연료가 누출 되어 화재 및 폭발사고로 이어질 가능성이 있는 곳이다. 나로우주센터에서 운용하는 우주발사체 나로호는 연료로 케로신(kerosene)을 사용하고, 산화제로 액화산소(LOX)를 사용한다. 발사대의 소화설비는 화재발생시 원격제어를 통해서 소화수와 소화약제를 분사하여 진화하는 방식으로 구성 되어 있다.

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Development of KSR-III Propulsion Feeding System (KSR-III 추진기관 공급계 개발)

  • 이대성;조인현;정태규;강선일;김용욱;정영석;권오성;정동호;오승협
    • Journal of the Korean Society of Propulsion Engineers
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    • v.6 no.4
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    • pp.37-45
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    • 2002
  • The development process of KSR-III propulsion feeding system is subscripted. The purpose of propulsion feeding system is to feed a certain amount of propellant from propellant tank to engine by the end of combustion. Pressure-fed liquid rocket, KSR-III has the unique characteristics of both pressure regulator and cavitation venturi as a passive flow control device. Main parameters of feeding system are confirmed by both water test and CFD(전산유체) technique. Flow control effect with venturi is confirmed by water test. Initial stabilization characteristic of pressure regulator is confirmed by real propellant test. And, to avoid the effect of resonance between rocket and feeding system, this article deal with POGO(포고) analysis to the feeding system.