• 제목/요약/키워드: responsible engineers

검색결과 293건 처리시간 0.027초

3 차원 주화성 모델 개발을 통한 흡착형 세포의 동적특성 연구

  • 송지환;김동철
    • 대한기계학회:학술대회논문집
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    • 대한기계학회 2008년도 추계학술대회A
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    • pp.1638-1642
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    • 2008
  • Cell migration is one of the essential mechanisms responsible for complex biological processes. Intensive researches have begun to elucidate the mechanisms and search intriguing conditions for efficient control of cell migration. One general mechanism which is widely applicable for cells including neutrophil, Escherichia coli and endothelial cell is chemotaxis. Especially, understanding the chemotactic mechanics of cell crawling has important implications for various medical and biological applications. The single cell study for chemotaxis has an advantage over studies with the population of cells in providing a clearer observation of cell migration, which leads to more accurate assessments of chemotaxis. In this paper, we propose a three-dimensional model considering a single crawling cell to study its chemotaxis. The semi-implicit Fourier spectral method is applied for high efficiency and numerical stability. The simulation results reveal rich dynamics of cell.

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요철이 설치된 회전하는 채널 내부의 유동 및 열전달의 큰에디모사 (Large Eddy Simulation of Flow and Heat Transfer in a Rotating Ribbed Channel)

  • 안준;최해천;이준식
    • 대한기계학회:학술대회논문집
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    • 대한기계학회 2003년도 추계학술대회
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    • pp.193-198
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    • 2003
  • A gas turbine blade has an internal cooling passage equipped with ribs, which can be modeled as a ribbed channel. We have studied a flow inside a ribbed channel using large eddy simulaton (LES) with a dynamic subgrid-scale model. The simulation results are compared with the experimental ones. The turbulence intensity and local heat transfer near the rib have not been well captured by the conventional Reynolds averaged Navier-Stokes simulation (RANS). However, these variables obtained by the present LES agree well with those from experiments. From the instantaneous velocity and temperature fields, we explain the mechanisms responsible for the local peaks in the heat transfer distribution along the channel wall. We have also investigated the effect of rotation on the flow and heat transfer in the ribbed channel.

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구동방법에 따른 TFT-LCD 화소 특성 시뮬레이션 (Simulations of TFT-LCD Pixel Characteristics with Different Driving Methods)

  • 흥성진;최종선;이신두
    • 대한전기학회:학술대회논문집
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    • 대한전기학회 2002년도 하계학술대회 논문집 C
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    • pp.1603-1605
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    • 2002
  • TFT-LCD is widely used for flat panel display. The large-size TFT-LCD panel requires a high speed driving and various driving methods because of signal delay, which is responsible for the shading effects. In this work, the floating and double driving methods are applied to Pixel Design Array Simulation Tool(PDAST) and the pixel characteristics of TFT-LCD array is simulated. Also, we have implemented the semi-empirical TFT model to PDAST, which makes to obtain a more accurate pixel characteristics.

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기술사마당_기술해설 - 베트남 락지아(Rach Gia) 우회도로 사업 실시설계소개 (Introduction of Detailed Design of Rach Gia Bypass Project in Vietnam)

  • 강희철
    • 기술사
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    • 제43권4호
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    • pp.44-49
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    • 2010
  • Th Rach Gia Bypass Project, to be implemented under EDCF Loan VNM-12, constitutes a strategically important part of the Greater Mekong Sub-region Southern Coastal Corridor Project(the GMS-SCCP). The main goal of the GMS strategy is to promote sustainable economic growth, improve employment, and achieve poverty reduction by tapping the comparative advantages of Vietnam, Cambodia and Thailand. As a project manager who once took a responsible position for the completion of RGBP's detailed design, I would like to briefly introduce what our design team including the local sub-contractors had performed for the D/Design of this Project last year, especially in the field of highway, bridge and soft soil treatment method widely used in Mekong Delta area. With the performance of nearly two Projects due to the V.O. in one year on the prescribed time, it was a hard year but a rewarding one. To expand our horizon more about overseas projects, several recommendations for the brighter future of overseas projects are shown herein this paper.

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폴리알킬시오펜의 전자 및 흡광특성 (Optical and Electronic Properties of Polyalkylthiophene)

  • 박대희
    • E2M - 전기 전자와 첨단 소재
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    • 제10권8호
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    • pp.778-782
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    • 1997
  • In this paper the electronic and optical properties of various poly(3-alkylthiophene)s differing in alkyl chain length were investigated. And their dependence on temperature were also investigated. The electrical conductivity decreased with the increase of alkyl chain length. In addition optical properties were changed due to the shift of edge energy which was caused by the change of the alkyl chain length and rise of temperature. The conformational change of poly(3-alkylthionphene) depending on the alkyl chain length is believed to be responsible to the change of electronic and optical properties of materials.

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직류전기철도의 누설전류 방지대책에 대한 고찰(2) 일본 (A review on the stray current countermeasures of DC electric railways(2) Japan)

  • 하윤철;배정효;하태현;이현구;김대경
    • 대한전기학회:학술대회논문집
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    • 대한전기학회 2006년도 제37회 하계학술대회 논문집 B
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    • pp.1083-1084
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    • 2006
  • The wide spread of DC electric railway systems such as urban rapid transits including heavy rail and light rail transits has significant ramification as the stray currents from return conductor rails can cause the electrochemical interference, that is, the electrolytic corrosion of both rails and outside underground metallic infrastructures. The immature understanding of either the railway authority who is responsible for establishing the necessary provisions at the design stage or the affected parties makes it difficult to prepare the optimum range of solutions for the long-pending interference problem. In Japan, however, numerous assessment studies have been carried out on the stray current interference, by which protective guidelines are provided by "Electrolysis Committee". In this paper, we review a guide book from "Tokyo Electrolysis Committee", namely, "Protective Methods for Stray Current Corrosion".

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Mini-MAP을 채택한 토큰-패싱 버스 네트워크의 MAC계층 구현에 관한 연구 (A Study on the Implementation of MAC Layer of Token-passing Bus Network Based on Mini-MAP)

  • 강문식;조병선;박민용;이상배
    • 전자공학회논문지B
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    • 제28B권5호
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    • pp.404-410
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    • 1991
  • In this paper,a network interface unit of token-passing bus network and its driving software are implemented based on Mini-MAP. This network interface unit performs the function of MAC layer which is responsible for transmission and reception of frames as well as the management of logical ring. The driving software performs the management of data buffer and the report of errors, if ocoured, to the higher layer. Motorola MC68824 of is used as a TBC(Token Bus Controller) and Intel80186 as a CPU for network interface unit. The operation of network interface unit is verified by self-test which checks the functioning of TBC and CPU. In addition each module of driving software is tested to check the functions regarding transmission and reception of frames.

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환형관에서 파형튜브가 압력강하에 미치는 효과 (Effects of the Corrugated Tubes on Pressure Drop in Concentric Annuli)

  • 안수환;손강필
    • 설비공학논문집
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    • 제13권9호
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    • pp.803-809
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    • 2001
  • The present paper presents the experimental results of pressure drip of water flow in annuli with spirally corrugated inner tubes in the turbulent flow regime. To understand the underlying physical phenomena responsible for heat transfer enhancement, pressure drop data documented elsewhere are combined to compare with those obtained from the present experiment for the Reynolds numbers of 1,000 to 8,000. Friction factors were found to be functions of trough depth, pitch and angle, and the annulus radius ratio. Friction factor increases in the spirally fluted tubes were larger than those in the corrugated tubes.

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VoIP Service 제공을 위한 Differentiated Service 와 MPLS (VoIP service support on Differentiated Service and MPLS)

  • 서진원;이병호
    • 한국정보과학회:학술대회논문집
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    • 한국정보과학회 2002년도 가을 학술발표논문집 Vol.29 No.2 (3)
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    • pp.124-126
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    • 2002
  • Voice over Internet Protocol(VoIP) is expected to be a major application on the Internet in the future This paper propose an approach to VoIP that uses Differentiated Service and Multi-protocol Label Switching(MPLS) to provide quantitative QoS guarantees over an IP network. An algorithm that determines QoS-constrained routes is proposed and a framework that uses such an algorithm for traffic engineering is outlined. the key component of this framework is a Centralize Resource Manager(CRM) responsible for monitoring and managing resources within the network and making all decisions to route/reroute traffic according to QoS requirement

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PCS를 위한 분산 호 처리 구조(DCPA)에서 캐쉬를 이용한 위치 추적 (Location tracking using cache in distributed call processing architecture for PCS)

  • 박선영;이원열;한기준
    • 전자공학회논문지S
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    • 제34S권8호
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    • pp.27-36
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    • 1997
  • In this paper, we propose a locating strategy using a cache based on the distributed call processing stucture. In our stategy, each originating call server, withc is responsible for call setup, has a cache to memorize the service ratio of call server which serves the called terminal.We present performance comparison of the proposed strategy with the existing strategy via simulation. We can reduce the cost for call setup because the originating call server can simpley establish a call without tracing the location of the called terminal. The proposed strategy also reduceds network loads caused by signaling at call setup time and lessens the frequency of queries for the database systems which can be a bottleneck when it serves many subscriber.

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