• 제목/요약/키워드: Re-order point

검색결과 141건 처리시간 0.026초

LNG 증발기체의 재액화 사이클에 대한 열역학 해석 (Thermodynamic Analysis of Re-liquefaction Cycle of LNG Boil-off Gas)

  • 진영욱;문정우;이윤표;장호명
    • 설비공학논문집
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    • 제19권7호
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    • pp.485-490
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    • 2007
  • The LNG BOG re-liquefaction system for LNG carriers was designed based on the Claude refrigeration cycle and the thermodynamic analysis was carried out in order to find the design point of the three heat exchangers constituting the system. The thermodynamic analysis revealed that the system state could be defined by the three cold endpoint temperatures of the three-pass heat exchanger. Hence the iso-lines of the specific liquefaction work, taken as the performance indicator, were presented in terms of those three temperatures and discussed. The system was found most economical when those three temperatures approached a single temperature of $-140^{\circ}C$ and thus this system state could be taken as the design point for the heat exchangers.

유리섬유 보강 플래스틱 Re-Bar 다발로 보강된 1방향 콘크리트 슬래브의 휨거동에 관한 실험적 연구 (Experimental Investigations on the Flexural Behavior of One-Way Concrete Slabs Reinforced with GFRP Re-Bar Bundle)

  • 윤순종;김병석;유성근;정재호;정상균
    • Composites Research
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    • 제16권3호
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    • pp.32-40
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    • 2003
  • 최근 철근의 부식과 관련된 철관콘크리트 바닥판의 내구성에 대한 문제점이 증가되면서 부식에 대한 저항성이 크며, 기존 구조용 재료에 비해 여러 가지 물리적, 역학적 장점을 가진 섬유보강플래스틱을 사용한 보강재의 사용성이 증가되고 있다. 본 연구는 GFRP Re-Bar 다발로 보강된 1방향 슬래브의 휨거동에 관한 실험적 연구로서, 국내에서 개발된 GFRP Re-bar의 인장시험을 수행하였으며, GFRP Re-Bar의 보강량을 증가시켜가며 단위 폭을 갖는 1방향 슬래브 실험체를 제작하고 3등분점 재하실험을 수행하였다. 각 실험체에 대한 이론적인 해석은 철근콘크리트 휨부재의 해석 및 설계방법을 수정, 보완하여 개발된 ACI Committee 440에 따라 수행하였으며, 실험결과와 이론적 해석결과를 비교, 분석하였다. 연구결과 ACI Committee 440에 의해 추정한 각 실험체의 하중­처짐 거동은 실험결과와 비교적 잘 일치함을 알 수 있었으며, FRP Re-Bar로 보강된 콘크리트 바닥판의 설계규준을 확립하기 위해서는 강도에 대한 한계상태뿐만 아니라 처짐 등 사용성에 대한 한계상태가 결정되어야 할 것이라 생각된다.

제주지역의 국가 기준점 정확도 분석 (Analysis of National Control Points in Jeju Area)

  • 정영동;양영보
    • 한국측량학회지
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    • 제23권3호
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    • pp.273-282
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    • 2005
  • 인공위성기술의 비약적인 발전은 각종 공간정보의 취득과 이를 응용하는 다양한분야에 광범위하게 이용되고 있다. 특히 GPS를 이용한 위치결정은 국가 기준계가 세계좌표계로 전환되는 시점을 맞이하여 더욱 활성화 될 전망이다. 현재 국토지리 정보원에서 발급하는 삼각점에 대한 성과는 신성과와 구성과로 구분하고 있고 2007년부터는 전면 세계좌표계로 전환할 예정에 있다. 현재 제주지역의 삼각점은 최초, 복구 또는 재설한 삼각점 성과 차이로 인해 측량자 들이 그 성과를 이용함에 있어 많은 혼란을 초래하고 있다. 따라서 본 연구는 제주지역의 현행삼각점간 부합관계를 점검하기 위해 1, 2등 삼각점을 기준으로 최초 측량 당시의 측지망을 재 구성하여 GPS 관측을 수행하였다. 관측 후 성과분석을 통해 삼각점간 부합되는 안정점을 추출하고 제주지역에 적합한 측지기준망을 구축하고 그 활용방안을 제시하였다. .

GPS에 의한 제주지역의 측지기준망 정확도 분석 (Accuracy Analysis on Geodetic Network in Jeju area using GPS)

  • 강상구;정영동;양영보
    • 대한공간정보학회지
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    • 제14권1호
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    • pp.65-74
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    • 2006
  • 인공위성기술의 비약적인 발전은 각종 공간정보의 취득과 이를 응용하는 다양한 분야에 광범위하게 이용되고 있다. 특히 GPS를 이용한 위치결정은 국가 기준계가 세계좌표계로 전환되는 시점을 맞이하여 더욱 활성화 될 전망이다. 현재 국토지리 정보원에서 발급하는 삼각점에 대한 성과는 신성과와 구성과로 구분하고 있고 2007년 부터는 전면 세계좌표계로 전환할 예정에 있다. 현재 제주지역의 삼각점은 최초, 복구 또는 재설한 삼각점 성과 차이로 인해 측량자 들이 그 성과를 이용함에 있어 많은 혼란을 초래하고 있다. 따라서 본 연구는 제주지역의 현행삼각점간 부합관계를 점검하기 위해 1, 2등 삼각점을 기준으로 최초 측량 당시의 재 구성하여 GPS 관측을 수행하였다. 관측 후 성과분석을 통해 삼각점간 부합되는 안정점을 추출하고 제주지역에 적합한 측지기준망을 구축하고 그 활용 가능성를 제시하였다.

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음식쓰레기를 활용한 비탈면 녹화기술의 식생기반재 배합비율에 관한 연구 (A Study on the Mixing Ratio of Food Waste on Slope Re-vegetation Base Materials)

  • 조동길;전기성;심윤진;김덕호;도종남;박미영
    • 한국환경복원기술학회지
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    • 제18권6호
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    • pp.215-226
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    • 2015
  • This study introduced food waste into re-vegetation base materials for surface loss recovery of carry-away highway cut slope. The object of this study is to derive the mixing ratio of food waste by conducting a test installation, monitoring, analysis and evaluation for recovery of carry-away highway cut slope. The following items were investigated and analyzed each experimental zone to draw mixing ratio of re-vegetation base materials and food waste : the physical and chemical properties of the vegetation base materials, soil-hardness, soil-humidity, left out and the collapsed point, established number of trees, species richness of grass species and tree species, coverage, pest status, and invasion of disturbance species. The re-vegetation method was evaluated by each experiment zone which has different mixing ratio. As a result, experiment zone A was rated 45 points out of 60 rating points as the best re-vegetation method. However, this study result has been derived from one construction and short-term monitoring. In order to derive the suitable and dependable mixing ratio, conducting an objective re-vegetation method evaluation and long-term experiment and monitoring is required.

라파엘전파와 감각적인 것의 나눔 (Pre-Raphaelites and The Distribution of the Sensible)

  • 이택광
    • 영어영문학
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    • 제55권2호
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    • pp.241-257
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    • 2009
  • The essay discusses the way in which the aesthetic of Pre-Raphaelites reformulates the habitual system of knowledge in the Victorian age by adapting $Ranci{\acute{e}}re^{\prime}s$ concept of aesthetics. $Ranci{\acute{e}}re$ develops an original theory of aesthetics, a regime of knowledge which enables to perceive and reflect art as such. In this way, aesthetics turns to be the logical system by which the consensus idea of the beautiful comes to exist. For $Ranci{\acute{e}}re$, aesthetics is an agreed system of the sensible and reproduces the habitual knowledge of the world. Therefore, a new aesthetic movement means an attempt to break the given aesthetics and reorients the new distribution of the sensible. The important point of $Ranci{\acute{e}}re^{\prime}s$ argument is that he does not presuppose the dimension beyond the present unlike Frankfurt School. What $Ranci{\acute{e}}re$ claims is that there is no such the aesthetic which can correct the instrumental reason, but rather an indifferent moment in which a worker finds out himself as a creator who can give rise to the new regime of the sensible and feels free from what he must work for. From this perspective, the essay explores the aesthetic of Pre-Raphaelites and its meaning in nineteenth century Britain. Pre-Raphaelites was an artist group who railed against a so-called academic style of paintings and created a new aesthetic criterion to describe the truth of the natural world. The essay examines the interrelationship between Pre-Raphaelites and photography that would enable them to re-distribute the sensible and produce a new way of seeing the order of things. This is related to the birth of a modern gaze as in the case of landscape paintings. What is crucial is that the distribution of the sensible is always-already doubled with the political. In short, Pre-Raphaeltes is not only an aesthetic movement but also a political pursuit to achieve a disenchanted perception of nineteenth century industrial capitalism.

점접촉 탄성 유체 윤활에서의 띠 무의 강도에 의한 유막 두께 측정 (Measurement of Film Thickness by Fringe Intensity Analysis in Point Contact Elastohydrodynamic Lubrication)

  • 장시열;최언진
    • 한국윤활학회:학술대회논문집
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    • 한국윤활학회 1999년도 제30회 추계학술대회
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    • pp.103-113
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    • 1999
  • Point contact film thickness in elastohydrodynamic lubrication (EHL) is analyzed by the image processing method for the monochromatic incident light. Interference between the reflected lights both on Cr coating of glass disk and on super finished ball makes circular fringes, which are regarded as film thickness together with numbering of fringe order. In this study, we developed technology to measure the film thickness by analyzing dark and bright intensity waves which results from monochrome green light. Two typical fringe patterns only with intensity values 3re examined for the measurement of point contact EHL film thickness. We expect that this technology will give valuable clue to improve color image processing analysis for high resolution of EHL film thickness with white incident light.

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Intervenient Stackelberg Game based Bandwidth Allocation Scheme for Hierarchical Wireless Networks

  • Kim, Sungwook
    • KSII Transactions on Internet and Information Systems (TIIS)
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    • 제8권12호
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    • pp.4293-4304
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    • 2014
  • In order to ensure the wireless connectivity and seamless service to mobile users, the next generation network system will be an integration of multiple wireless access networks. In a heterogeneous wireless access system, bandwidth allocation becomes crucial for load balancing to avoid network congestion and improve system utilization efficiency. In this article, we propose a new dynamic bandwidth allocation scheme for hierarchical wireless network systems. First, we derive a multi-objective decision criterion for each access point. Second, a bargaining strategy selection algorithm is developed for the dynamic bandwidth re-allocation. Based on the intervenient Stackelberg game model, the proposed scheme effectively formulates the competitive interaction situation between several access points. The system performance of proposed scheme is evaluated by using extensive simulations. With a simulation study, it is confirmed that the proposed scheme can achieve better performance than other existing schemes under widely diverse network environments.

Cycle Analysis on LNG Boil-off Gas Re-Liquefaction Plant

  • Chin, Y.W.
    • 한국초전도ㆍ저온공학회논문지
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    • 제8권4호
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    • pp.34-38
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    • 2006
  • Cycle analysis was performed in order to find the optimum design point of the LNG Boil-off gas re-liquefaction system. Thermodynamic analysis revealed the system could be defined by three state variables. Thus the system performance could be described by the three cold endpoint temperatures of the three-pass heat exchanger. This enabled us to investigate the cycle performance in terms of the heat exchanger parameters. To get access to the cycle states of higher system performances, larger heat exchangers were found necessary. Also the thermal pinch in cryogenic heat exchangers was found to act as a limiting factor to the system performance.

초고층 건축공사의 특수성을 고려한 최적 자재 재고 관리 방안에 관한 연구 -철근공사를 중심으로- (An optimal inventory management system for high-rise building -Focused on Re-bar Works-)

  • 김근환;이수환;윤정숙;박경모;김창덕
    • KIEAE Journal
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    • 제13권1호
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    • pp.151-157
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    • 2013
  • Since high-rise building construction sites are usually located in crowded city areas, sufficient spaces for the inventories of key materials are rarely available. This spatial constraints have been one of the critical challenge that may cause productivity loss and increasing costs of the high-rise building construction projects. The proper material inventory management is certaing a key to the success of high-rise building construction projects as it handles difficulty of securing material stock yards, changes in demands, uncertain delivery time through integrating the construction schedules and actively responding to the key materials attributes. In this light, this research analyzes the latest inventory model, (Q,r) model, in accordance with the high rise building characteristics. This research suggests an optimal inventory management of re-bar considering various demands and lead times. The case study is also presented with regard to the re-bar inventory management.