• 제목/요약/키워드: Dividing flow

검색결과 153건 처리시간 0.029초

복합상영관 화재에 대한 화재모델링의 적용 (A Study on the Application of Fire Modeling for Multiplex Cinema Theater)

  • 허준호;김종훈;노삼규;김운형
    • 한국화재소방학회논문지
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    • 제18권1호
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    • pp.42-48
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    • 2004
  • 다중이용시설의 화재 시 온도분포 및 연기유동 모델링은 결정론적 모델(Deterministic Model)인 존모델 (Zone Model)과 필드모델(Field Model)이 주로 사용되고 있다. 존모델은 공간을 두개의 지역으로 구분하여 화재현상을 분석하고, 필드모델은 공간을 다수의 Cell로 구분하여 분석하고 있으나 두 모델의 비교치에 대해서는 효용성 검증에 어려움을 겪고 있다. 따라서 화재현상의 모델링에 따른 수치적 이해와 관련자료의 검증을 통하여 실 상황에 보다 근접한 새로운 모델의 개발이 요구된다. 본 논문에서는 두 모델을 복합상영관의 실내공간에 적용하여 그 효용성을 분석해본 결과 공간 평균분포도에서는 존모델이, 세부적 공간현상에서는 필드모델의 적용이 적절한 것으로 판단된다. 또한 구체적인 화재의 성상과 감지기의 위치선정, 연기제어를 위한 제연설비의 검토를 위해서는 필드모델의 활용이 더욱 효과적이다.

High Performance QoS Traffic Transmission Scheme for Real-Time Multimedia Services in Wireless Networks

  • Kang, Moonsik
    • IEIE Transactions on Smart Processing and Computing
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    • 제1권3호
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    • pp.182-191
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    • 2012
  • This paper proposes a high performance QoS (Quality of Service) traffic transmission scheme to provide real-time multimedia services in wireless networks. This scheme is based on both a traffic estimation of the mean rate and a header compression method by dividing this network model into two parts, core RTP/UDP/IP network and wireless access parts, using the IEEE 802.11 WLAN. The improvement achieved by the scheme means that it can be designed to include a means of provisioning the high performance QoS strategy according to the requirements of each particular traffic flow by adapting the header compression for real-time multimedia data. A performance evaluation was carried out to show the effectiveness of the proposed traffic transmission scheme.

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2-방정식 난류모델을 이용한 스포일러 천이적 공력특성의 파라메트릭 연구 (Parametric Study of Transient Spoiler Aerodynamics with Two-Equation Turbulence Models)

  • 최성욱;장근식;옥호남
    • 한국전산유체공학회:학술대회논문집
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    • 한국전산유체공학회 2000년도 추계 학술대회논문집
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    • pp.15-24
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    • 2000
  • The transient response of an airfoil to a rapidly deploying spoiler is numerically investigated using the turbulent compressible Navier-Stokes equations in two dimensions. Algebraic Baldwin-Lomax model, Wilcox $\kappa-\omega$ model, and SST $\kappa-\omega$ turbulence model are used to calculate the unsteady separated flow due to the rapid spoiler deployment. The spoiler motion relative to a stationary airfoil is treated by an overset grid hounded by a Dynamic Domain-Dividing Line which has been devised by the authors. The adverse effects of the spoiler influenced by the spoiler location and the hinge gap are expounded. The numerical results are in reasonably good agreement with the existing experimental data.

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박용 대형 저속 디젤기관 연료분사계통의 시뮬레이션에 관한 연구 (A Study on the Simulation of the Fuel Injection System in a Large Low-speed marine Diesel Engine)

  • 이창식
    • 한국마린엔지니어링학회:학술대회논문집
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    • 한국마린엔지니어링학회 2000년도 춘계학술대회 논문집(Proceeding of the KOSME 2000 Spring Annual Meeting)
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    • pp.36-44
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    • 2000
  • In his study the simulation was carried out by simplifing and modeling dividing into fuel injectioin pump high pressure pipe and fuel injection valve in the fuel injection system of a low speed marine diesel engine. A computer simulation model was developed using the method of characteristics to analyze the unsteady flow in the fuel injection system considering cavitation and variation of fuel density and bulk modulus. Comparison was commenced between the calculated data and experimental data of pressure and injection quantity at the high pressure distributor in fuel injection system for the training ship "M/V hanara" the effects of the high pressure pipe length diameter plunger diameter nozzle openning pressure were also investigated by simulating results.g results.

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벽식(壁式) 아파트의 택트공정(工程)계획의 성공요인 분석에 관(關)한 연구(硏究) (The Success Factors of Scheduling Using the TACT Technique in Wall Type Apartment House Construction)

  • 김준호;김광희;조형근
    • 한국건축시공학회지
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    • 제6권1호
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    • pp.79-86
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    • 2006
  • Recently, the construction companies show lots of interest in reducing the construction duration of apartment housing project in Korea. Therefore, the purpose of this study is to investigate the success factors of scheduling using the TACT technique in wall type apartment house construction for managing the construction schedule effectively. For appling the tact scheduling technique to wall type apartment house construction, the success factors can be summarized as follows : (1) zoning the horizontal and vortical work area properly, (2) preparing the flow chart of finishing works, (3) minimizing the undefined activity like chipping off the concrete wall, (4) reordering the construction activities for keeping up the continuity of works in winter season, (5) dividing the amount of work for minimizing the delay time of any activity, etc.

LIGA process를 이용한 micro CPL(Capillary Pumped Loop)제작 (manufacturing micro CPL (Capillary Pumped Loop)by using LIGA process)

  • 조진우;정석원;박준식;박순섭
    • 대한전기학회:학술대회논문집
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    • 대한전기학회 2001년도 하계학술대회 논문집 C
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    • pp.1881-1883
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    • 2001
  • We manufactured a micro CPL by LlGA process, a new conceptual ultra-fine and precise forming method, using X-ray lithography process. We fabricated a BN X-ray mask having properties of good X-ray transmittance and large mechanical strength. Micro CPL was manufactured by dividing into an upper plate and a low plate. Each of plates was bonded by Ag paste screen printing. The upper plate was fabricated on glass wafer to observe flow and phase transformation of cooling solution. The lower plate was manufactured by Cu electroplating for good heat transmission. Precision of inner Parts, micro pin and micro channel, of manufactured micro CPL is under ${\pm}2{\mu}m$.

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진공청소기용 팬모터의 소음 및 진동모드 분석을 위한 3차원 레이저 진동측정 (3-D Laser Vibration Measurement for Nose and Vibrating Mode Analysis of Fan Motor in a Vacuum Cleaner)

  • 김재열;곽이구;송경석;안재신;이창선;윤성운
    • 한국정밀공학회:학술대회논문집
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    • 한국정밀공학회 2003년도 춘계학술대회 논문집
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    • pp.942-945
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    • 2003
  • Noise cause is dividing to fluid noise by exhaust flow of fan and vibration noise by rotational vibration of motor. Until now, measuring method has been used to measure vibration by the accelerometer, this method has been not measured for the vibration in some parts of brush and commutator because of motor construction. This research was purposed on the accurate analysis. using laser vibration analyzer, of noise cause against the difficult part in old times. By using this measured data, we would like to use for the design of silent motor.

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3차원 레이저 진동측정기를 이용한 고속회전 모터의 진동특성 분석 (Vibrating Characteristics Analyze of High Revolrution Motor by 3-D Laser Vibration Analyzer)

  • 김재열;김창현;송경석;양동조;곽이구;이창선
    • 한국공작기계학회:학술대회논문집
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    • 한국공작기계학회 2003년도 춘계학술대회 논문집
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    • pp.179-184
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    • 2003
  • Noise cause is dividing to fluid noise by exhaust flow of fm and vibration noise by rotational vibration of motor. Until now, measuring method has been used to measure vibration by the accelerometer, this method has been not measured for the vibration in some parts of brush and commutator because of motor construction. This research was purposed on the accurate analysis, using laser vibration analyzer, of noise cause against the difficult part in old times. By using this measured data, we would like to use for the design of silent motor.

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Optimal design of Natural Fiber Composite Structure for Automobile

  • Lee, Haseung;Kong, Changduk;Park, Hyunbum
    • International Journal of Aerospace System Engineering
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    • 제3권1호
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    • pp.21-24
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    • 2016
  • In this study, a optimal design on the hood automotive using eco-friendly natural fiber composites is performed. The hood of an automobile is determined by dividing the Inner panel shape through optimization phase to outer panel and inner panel. It was performed to optimize the size of the thickness of the inner panel and the outer panel by applying a flax/epoxy composite materials. The optimized shape was evaluated for weight-lightening, stability and the pedestrian collision safety. Through the resin flow analysis are confirmed to molding possibility judgment of product.

Let-List로 부터 Schematic Diagram 자동 생성기의 배치 알고리즘 (Placement Algorithm for Automatic Generator of Schematic Diagram Using Net-List)

  • 김환석;이천희
    • 대한전자공학회논문지
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    • 제26권12호
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    • pp.2039-2045
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    • 1989
  • In this paper, we developed placement algorithm for drafting logic schmeatics. The algorithm of this system is to base placement on signal flow as opposed to connectivity. The key idea of this algorithm is that by dividing the schematic into simpler acyclic, uni-directional graphs, called tree. Then the components of tree and their interconnections have the characteristics that they can be laid out symmetrically without any crossovers. The interconnectivity between the trees are analyzed and a placement scheme is determined for them. Also, the trees are expended into their respective components. This algorithm is divided into four main phases: Initiate, Divide, Merge, Placement.

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