• Title/Summary/Keyword: Parallel-flow

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Experimental Study on Distally Based Free Flap Using Retrograde Arterial Flow (역행성 동맥 혈류를 이용한 원위 유리피판술의 실험적 연구)

  • Lee, Min-Goo;Minn, Kyung-Won
    • Archives of Reconstructive Microsurgery
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    • v.7 no.1
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    • pp.15-19
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    • 1998
  • Microsurgical free-tissue transfer has allowed surgeons to salvage injured limbs but choosing appropriate healthy recipient vessels has proved to be a difficult problem. Retrograde flow flaps are established in island flaps. Retrograde flow anastomosis could prevent the possible kinking and twisting of the arterial anastomosis. By not interrupting the proximal blood flow to the fracture or soft tissue defect site, the compromise of fracture or wound healing might be prevented. We wished to estabilish an animal model in rat for a retrograde arterial flow based free flap. Nembutal-anesthetized male rats; weighing 250 to 300 gm, were used. The femoral artery and common carotid artery were exposed and divided. The systemic and retrograde arterial pressure were quantified by utilizing a parallel tubing system connected with peripheral arterial line. In this study, the retrograde flow was not pulsatile and the retrograde arterial pressure was 64-65mmHg, with a mean arterial pressure of 106-109mmHg. An epigastiic skin flap, measuring $3{\times}3cm$, was raised with its vascular pedicle. The epigastric free flap was transfered in the same rat from femoral vessels to carotid vessels in end to end fashion. We anastomosed the donor arteries to the distal parts of the divided recipient arteries and the donor veins to the proximal parts of the recipient veins. Twelve experiments were performed and the transplantations succeeded in 75 percent of them. In the remaining 25 percent, the experiments failed due to thrombosis at the site of anastpmosis, or other causes. This animal model represents an excellent example of retrograde arterial flow free flap transfer that is reliable.

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An efficient architecture for motion estimation processor satisfying CCITT H.261 (CCITT H.261를 위한 효율적인 구조의 움직임 추정 프로세서 VLSI 설계)

  • 주락현;김영민
    • Journal of the Korean Institute of Telematics and Electronics B
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    • v.32B no.1
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    • pp.30-38
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    • 1995
  • In this paper, we propose an efficient architecture for motion estimation processor which performs one of essential functions in moving picture coding algorithms. Simple control mechanism of data flow in register array which stores pixel data, parallel processing of pixel data and pipelining scheme in arithmetic umit allow this architecture to process a 352*288 pixel image at the frame rate of 30fs, which is compatable with CCITT standard H.261.

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Dust collector strainer and carbon filter pressure permeation analysis (흡연집진기 내 스트레이너 및 카본필터 압력투과 해석)

  • Lee, Chi-Woo
    • Journal of Power System Engineering
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    • v.19 no.4
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    • pp.5-10
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    • 2015
  • Dust collector is one of the most widely used equipment among the method of separating particles, it filters exhaust gas having various kinds of dusts through several filters installed on parallel. This research investigated the moving characteristic of Honeycomb-type carbon filter in pressure drop of smoking collector's ventilation system. It also compared pressure transmission coefficient through pressure drop according to flow velocity change.

Parallelization of 3-dimensional Multigrid DADI Method (3차원 다중격자 DADI 방법의 병렬처리)

  • Seong Chun-Ho;Park Su-Hyeong;Gwon Jang-Hyeok
    • 한국전산유체공학회:학술대회논문집
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    • 1998.05a
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    • pp.49-54
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    • 1998
  • 3-dimensional Euler solver is parallelized. The spatial discretization method is the 2nd order TVD scheme and DADI method with multigrid is used as a time integration. In order to parallelize this solver, the domain decomposition method with overlapped grid and message passing techniques are used. The informations on the each inter-processor bound-aries are communicated with MPI library. Finally, the parallel performance repsented by calculating the ONERA M6 wing at transonic flow condition using CRAY T3E and C90.

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3D numerical simulation of temperature on Pilot tube

  • Ying Wang;Baogeng Ding
    • 한국전산유체공학회:학술대회논문집
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    • 2006.05a
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    • pp.248-251
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    • 2006
  • Multi-physics problem is considered for the Pitot tube located in uniform freon gas flow with high Mach number and the 3D numerical results of temperature on Pitot tube is given. The model is created by using structural module of ANSYS, the grids are obtained by ICEM, and the problem is solved and the data post-processing is done by CFX.

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An Efficient Distributed Parallel Processing in Optimal Power Flow (최적조류계산의 효율적인 분산병렬처리)

  • Kim, Bal-Ho;Kim, Jin-Ho;Heo, Don
    • Proceedings of the KIEE Conference
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    • 1999.11b
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    • pp.434-437
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    • 1999
  • 본 연구에서는 워크스테이션 상에서 최적조류계산의 효율적인 분산병렬처리 기법을 개발하였다. 본 연구의 결과를 실제로 2587개의 송전선을 포함하는 미국 ERCOT 계통에 대하여 사례 연구한 결과 성능이 뛰어남을 알 수 있었다. 본 연구는 최적 조류계산을 병렬 처리하는 일반적인 방식을 제시해 줄 수 있을 것이라 생각된다.

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THE PROCESS OF THE DEVELOPMENT OF HYPOXIA IN AN ABNORMAL BLOOD FLOW II

  • Kwak, Min-Kyu;Go, Jae-Gwi
    • Journal of the Korean Society for Industrial and Applied Mathematics
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    • v.11 no.2
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    • pp.59-66
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    • 2007
  • The oxygen distribution at steady state is analyzed mathematically in a hexagonal cylinder. The domain is penetrated by parallel cylindrical capillaries of different oxygen squirt. Asymptotic solution is used to determine the effect of axial diffusion. Oxygen concentration profiles are displayed at some positions of capillary-beds. At the venous end some tissue areas suffer from a shortage of oxygen.

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A Development of Distributed Parallel Processing algorithm for Power Flow analysis (유기EL과 무기EL에 관한 연구)

  • Lee, Han-Sung
    • Proceedings of the KIEE Conference
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    • 2001.07e
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    • pp.67-71
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    • 2001
  • Nowdays, we can communicate using Information Technology such as internet, personal computer, mobile phone etc. To protect global environment, it is also reqired to invent products efficiently reduce energy consumption. here, I studied organic EL and inorganic EL because organic EL display is appropriate device as light, thin, energy-saying display following CRT, LCD. As a result, I realized that we are supposed to study more on invention, efficiency and mass-production of materials. Comparing with another display, however, it would be marketable in few years, considering short history of its full-scaled studies.

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