• 제목/요약/키워드: Dwell Time

검색결과 240건 처리시간 0.026초

건축학적(建築學的) 해석(解析)에 의한 성막건축(聖幕建築)의 재현설계(再現設計) 기준설정(基準說定)에 관한 연구(硏究) (A Study on the Standard Requirements of the Tabernacle's Representation Drawings through Architectural Analysis)

  • 오태주;이상호
    • 한국실내디자인학회논문집
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    • 제16권1호
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    • pp.108-118
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    • 2007
  • The tabernacle architecture is the paradigm of the new testaments and the modern church, and has been from the temples to synagogues, the Old Testaments to the New Testaments, and from present to future. Nevertheless, research on the Tabernacles has never been studied architecturally but has only been researched Biblically or partially. This would be because people interested in the tabernacle lack in architectural knowledge, and architects would be limited theologically. Furthermore, the start of church architecture until now was the architecture of the Roman-court style and the Greece Temple as the exterior, such as the Basilica, a non-Christian, strangely styled piece of architecture, which was seen as the basis of the church architectural style, which is a great mistake, due to the effect of modern architectural educational system with the central figure of humanism and western styled architecture. The measurement and the pattern of the Tabernacle architecture were not recorded in the Bible in order to produce the shape of the Tabernacle. The 'Architecture of God' was designed for the very first time on Earth so that He could dwell among His people.

부산 컨테이너 부두의 효율적인 운영방안에 관하여 (On Improving the Productivity of Busan Container Terminal)

  • 이병국;이철영
    • 한국항해학회지
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    • 제11권1호
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    • pp.39-65
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    • 1987
  • Since the middle of 1950's, containerization has been rapidly spread over the world in virtue of great merits providing to interensts, and the fundamental changes in port management and prot operations are resulted. As the container terminal is a complex system which is consisted of various subsystems, the treatment for improving the productivity is required in a comprehensive fashion, both in each of its parts and as an integrated system. This paper aims to make an intensive analysis of the Busan Container Terminal system, especially focusing on its subsystems such as ship operation system, storage system and transfer system. First of all, the intrinsic capacity of various subsystems is calculated and it is checked whether the current operation is being performed effectively through the formal analysis. Secondly, the suggestion is presented to improve the operation by considering the throughput that the port of Busan will have to accept in the near future. The results are as follows; 1) As the inefficiency is due to the imbalance between various subsystems at Busan terminal, transfer equipment level must be up to 31% for straddle carrier and 67% transfer crane above all. 2) The yard capacity must be increased by reducing the free dwell time of containers in order to accept the traffic volume smoothly in the near future. 3) The better way to reduce the port congestion is to change berthing rule from the FIFP to the Pre-allocated system by considering the ship arrival pattern.

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연료전지 집전판용 주석도금 동판의 열 열화에 따른 금속간화합물 성장 및 비저항 변화 (Resistivity Changes and Intermetallic Growth After Thermal Aging of Matte Tin-Plated Copper Sheet for Current Collector in Fuel Cell)

  • 김재훈;김주한;한상옥;구경완;금영범;정귀성;고행진
    • 대한전기학회:학술대회논문집
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    • 대한전기학회 2009년도 제40회 하계학술대회
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    • pp.2067_2068
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    • 2009
  • Resistivity changes and intermetallic growth after thermal aging of Matter tin-plated copper sheet for current collector in fuel cell were investigated to survey the diffusion of Cu into Sn in interface and surface. The results show that the intermetallic growth and resistivity depended on thermal aging temperature and dwell time. In Sn plate on a Cu substrate, $Cu_6Sn_5({\mu})$ and $Cu_3Sn({\varepsilon})$ intermetallics layer were formed at plate/substrate interface. $Cu_6Sn_5({\mu})$ intermetallics layer gradually changed $Cu_3Sn({\varepsilon})$. Moreover Cu get through Sn layer and it was diffused in the surface at $200^{\circ}C$. On the other hand, only $Cu_3Sn({\varepsilon})$ intermetallics layer were formed at plate/substrate interface at $300^{\circ}C$. Consequently, the intermetallics formation, thermal condition and oxidation of surface, causes increase in the resistivity of Tin-plated copper sheet.

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시효처리된 연료전지 집전판용 Matte 주석도금 동판의 고온열화 거동과 비저항변화 (Degradation Behavior and Resistivity Changes After Thermal Aging of Matte Tin-Plated Copper Sheet for Current Collector in Fuel Cell)

  • 김주한;김재훈;구경완;금영범;정귀성;고행진;한상옥
    • 전기학회논문지
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    • 제58권8호
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    • pp.1559-1565
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    • 2009
  • Resistivity changes and intermetallic growth after thermal aging of Matter tin-plated copper sheet for current collector in fuel cell were investigated to survey the diffusion of Cu into Sn in interface and surface. The results show that the intermetallic growth and resistivity depended on thermal aging temperature and dwell time. In Sn plate on a Cu substrate, Cu6Sn5(${\mu}$) and Cu3Sn(${\varepsilon}$) intermetallics layer were formed at plate/substrate interface. Cu6Sn5(${\mu}$) intermetallics layer gradually changed Cu3Sn(${\varepsilon}$). Moreover Cu get through Sn layer and it was diffused in the surface at $200^{\circ}C$. On the other hand, only Cu3Sn(${\varepsilon}$) intermetallics layer were formed at plate/substrate interface at $300^{\circ}C$. Consequently, the intermetallics formation, thermal condition and oxidation of surface, causes increase in the resistivity of Tin-plated copper sheet.

가시화를 이용한 정적연소기에서 점화장치가 화염전파에 미치는 영향에 관한 연구 (A Visualization Study on the Effects of Ignition Systems on the Flame Propagation in a Constant Volume Combustion Chamber)

  • 송정훈;선우명호
    • 대한기계학회논문집B
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    • 제24권12호
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    • pp.1652-1661
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    • 2000
  • A visualization study using the schlieren method is adopted in an optically-accessible, cylindrical constant volume combustion chamber to identify the mechanism of ignition energy and ignition system interaction in spark ignited, lean gasoline-air mixture. In order to research the effects of ignition system on flame propagation, two kinds of ignition system are designed, and several kinds of spark plugs are tested and evaluated. To control the discharge energy, the dwell time is varied. The initial flame development is quantified in terms of 2-D images which provides information about the projected flame area and development velocity as a function of ignition system and discharge energy. The results show that high ignition energy and extended spark plug gap can shorten the combustion duration in lean mixtures. The material, diameter and configuration of electrodes the flame development by changing the transfer efficiency from electrical energy to chemical energy and discharge energy. However these factors do not affect of flame development as much a ignition energy or extended gap does.

WC-Ni-Si-B4C계 초경합금 제조 및 스테인레스 스틸과의 확산접합 (Fabrication of WC-Ni-Si-B4C Composite and Diffusion Bonding with Stainless Steel)

  • 원종운
    • 한국생산제조학회지
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    • 제24권6호
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    • pp.594-598
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    • 2015
  • The effects of Ni on the mechanical properties of WC-Xwt.%Ni-1.5wt.%Si-1.1wt.%$B_4C$ composite (X = 21.6, 23.6, 25.6 and 27.6 wt.%) were investigated in order to replace Co with Ni as the binder metal for hard materials based on WC-Co system. Using X-ray diffraction, optical microscopy, field-emission scanning electron microscopy results, the microstructure, pore distribution and grain size of the composites sintered at $1,150^{\circ}C$ were examined with different fraction (X = 21.6, 23.6, 25.6 and 27.6 wt.%) of binder metal Ni. The average WC grain size of the $WC-Ni-Si-B_4C$ composites was about $1{\mu}m$. The Rockwell hardness : A (HRA) and transverse rupture strength were about 88HRA and $110kgf/mm^2$, respectively. The obtained sample was bonded with SM45C at a temperature of $1,050^{\circ}C$. The thickness and mechanical properties of the bonded area were investigated with different dwell time at a bonding temperature of $1,050^{\circ}C$.

곡 블록 자동화를 위한 지능형 용접 캐리지 개발 (Development of a Intelligent Welding Carriage for Automation of Curved Block)

  • 최희병;문종현;전완열;김세환
    • 대한조선학회 특별논문집
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    • 대한조선학회 2005년도 특별논문집
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    • pp.171-176
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    • 2005
  • This paper presents a novel Intelligent-Welding-Carriage (IWC) for automation of curved block in shipbuilding. The curved block is usually used in both front and back side of the ship. In curved block root gap is big, 1-7 (mm) and inclination, 0-30 (deg). Since available conventional carriage type is limited to use below root gap of 3 (mm), only manual welding is employed in curved block. To adopt an IWC in curved block, it requires control of the welding conditions, i.e., voltage. current, weaving speed, dwell time and travel speed, with respect to root gap and inclination to achieve good welding qualify. In this paper, an IWC is developed for automization of welding operation to accommodate gap and inclination. Kinematics model and dynamics using Lagrangian formulation of the manipulator is introduced. IWC utilizes a database to perform accurate welding. The database is programmed based on numerous experimental test results with respect to gap, inclination, material, travel speed, weaving condition, voltage, and current. Finally, experimental result using PID control is addressed for verifying the trajectory tracking accuracy of end-effector.

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실험계획법을 이용한 탄소섬유/페놀수지의 강화 cycle연구

  • 하헌승;이진용;조동환;윤병일
    • 한국재료학회지
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    • 제3권5호
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    • pp.514-520
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    • 1993
  • 다구찌의 실험계획기법을 이용하여 탄소섬유/페놀수지의 결화싸이클을 연구하였다. 본 연구에서는 1인자 2수준과 7인자 3수준으로 구성된 $L_{18}(2^1 \times 3_7)$ 직교배열표를 사용하였고, 특성치로 굴곡강도와 기공률을 선정하여 실험하였다. 실험계획법의 압축성형 인자로는 8개의 성형인자(승온속도, 가압온도, 성형압력, 경화온도, 경화온도에서의 유지시간, 냉각속도 및 탈기포)가 고려되었으며, 이들 성형인자가 탄소섬유/페놀수지 복합재료의 물성에 미치는 영향을 고찰하였다. 분산분석법으로 실험결과를 분석한 결과, 탄소섬유/패놀수지 복합재료의 굴곡강도에 가장 큰 영향을 미치는 성형인자는 성형압력이고, 기공률에 가장 큰 영향을 미치는 성형인자는 경화온도임이 밝혀졌다.

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Effects of Healing Agent on Crack Propagation Behavior in Thermal Barrier Coatings

  • Jeon, Soo-Hyeok;Jung, Sung-Hoon;Jung, Yeon-Gil
    • 한국세라믹학회지
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    • 제54권6호
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    • pp.492-498
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    • 2017
  • A thermal barrier coating (TBC) with self-healing property for cracks was proposed to improve reliability during gas turbine operation, including structural design. Effect of healing agent on crack propagation behavior in TBCs with and without buffer layer was investigated through furnace cyclic test (FCT). Molybdenum disilicide ($MoSi_2$) was used as the healing agent; it was encapsulated using a mixture of tetraethyl orthosilicate and sodium methoxide. Buffer layers with composition ratios of 90 : 10 and 80 : 20 wt%, using yttria stabilized zirconia and $MoSi_2$, respectively, were prepared by air plasma spray process. After generating artificial cracks in TBC samples by using Vickers indentation, FCTs were conducted at $1100^{\circ}C$ for a dwell time of 40 min., followed by natural air cooling for 20 min. at room temperature. The cracks were healed in the buffer layer with the healing agent of $MoSi_2$, and it was found that the thermal reliability of TBC can be enhanced by introducing the buffer layer with healing agent in the top coat.

복수적분 시구간 직렬탐색 시스템에서 부분 상관기를 이용한 Kronecker 부호의 특성 분석 (Analysis of Kronecker Sequence with Partial-Period Correlation in a Multiple-dwell Serical Serarch System)

  • 임연주;박상규
    • 한국통신학회논문지
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    • 제25권8B호
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    • pp.1333-1340
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    • 2000
  • 본 논문에서는 고속의 초기동기가 가능한 Kronecker 부호를 DS/CDMA 시스템의 확산부호로 하여 패킷 무선 데이터 통신에서의 사용을 위한 타당성을 보인다 먼저 Kronecker 부호의 생성방법 상관특성을 보여 대체적인 부호의 특성을 밝히고 부분 상관기를 이용할 수 있음을 보인다 더 나아가 PN 부호와 같은 평균 초기동기획득 시간을 가질 때의 Kronecker 부호의 오경보 확률과 실패 확률을 구하여 Kronecker 부호가 PN 부호보다 더 높은 동기 확률을 가짐을 보임으로써 패킷 통신에서 Kronecker 부호를 사용할 수 있는 가능성을 확인한다.

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