• 제목/요약/키워드: Chimera

검색결과 141건 처리시간 0.024초

비정상 Euler 방정식을 이용한 Chimera 기법의 병렬처리에 관한 연구 (A Study of Parallel Implementations of the Chimera Method using Unsteady Euler Equations)

  • 조금원;권장혁;이승수
    • 한국전산유체공학회지
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    • 제4권3호
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    • pp.52-62
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    • 1999
  • The development of a parallelized aerodynamic simulation process involving moving bodies is presented. The implementation of this process is demonstrated using a fully systemized Chimera methodology for steady and unsteady problems. This methodology consists of a Chimera hole-cutting, a new cut-paste algorithm for optimal mesh interface generation and a two-step search method for donor cell identification. It is fully automated and requires minimal user input. All procedures of the Chimera technique are parallelized on the Cray T3E using the MPI library. Two and three-dimensional examples are chosen to demonstrate the effectiveness and parallel performance of this procedure.

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재조합 대장균을 이용한 GFP-AFP Chimera 단백질 과량발현 및 특성 파악연구 (Overexpression of GFP-AFP Chimera Protein using Recombinant Escherichia coli and Analysis of Anti-freezing Characteristics)

  • 고지선;홍순호
    • KSBB Journal
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    • 제28권5호
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    • pp.310-314
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    • 2013
  • Antifreeze peptide from Myoxocephalus octodecemspinosus was overexpressed and purified in Escherichia coli. Green fluorescence protein-AFP chimera was constructed by integrating gfp and afp genes. Produced GFP-AFP chimera protein was purified using polyhistidine tag which was inserted at C-terminus. By addition of GFP-AFP chimera protein, freezing point of elution buffer was decreased from $-13^{\circ}C$ to $-20^{\circ}C$. This result suggested that GFP-AFP chimera can be considered as a potential candidate of novel inhibitor for gas hydrates.

Chimera 격자기법을 이용한 자동차 주위의 유동장 해석 (Analysis of the flow field around an automobile with Chimera grid technique)

  • 안민기;박원규
    • 한국전산유체공학회지
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    • 제3권2호
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    • pp.39-51
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    • 1998
  • This paper describes the analysis of flow field around an automobile. The governing equations of the 3-D unsteady incompressible Navier-Stokes equations are solved by the iterative time marching scheme. The Chimera grid technique has been applied to efficiently simulate the flow around the side-view mirror. To validate the capability of simulating the flow around a ground vehicle, the flows around the Ahmed body with 12.5$^{\circ}$ and 30$^{\circ}$ of slant angles are simulated and good agreements with experiment and other numerical results are achieved. To validate Chimera grid technique, the flow field around a cylinder was also calculated. The computed results are also well agreed with other numerical results and experiment. After code validations, the flow phenomena around the ground vehicle are evidently shown. The flow around the side-view mirror is also well simulated using the Chimera grid technique.

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Chimera 격자계를 이용한 Euler/Navier-Stokes Solver의 개발 (Development of Euler/Navier-Stokes Solver using Chimera Grid Method)

  • 이승수;박민우;조금원;권장혁
    • 한국전산유체공학회:학술대회논문집
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    • 한국전산유체공학회 1998년도 추계 학술대회논문집
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    • pp.141-146
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    • 1998
  • An Euler/Navier Stokes solver has been developed for the analysis of steady and unsteady flows. The $q-{\omega}$ turbulent model has been incorporated into the solver in strongly coupled manner for stability and robustness. A new Chimera hole cutting algorithm, Cut-paste algorithm, has been devised for automatic Chimera hole cutting. Number of viscous/inviscid numerical computations demonstrate the accuracy and the versatility of the solver.

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Chimera 기법의 병렬처리에 관한 연구 (A Study of Parallel Implementations of the Chimera Method)

  • 조금원;권장혁;이승수
    • 한국전산유체공학회:학술대회논문집
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    • 한국전산유체공학회 1999년도 춘계 학술대회논문집
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    • pp.35-47
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    • 1999
  • The development of a parallelized aerodynamic simulation process involving moving bodies is presented. The implementation of this process is demonstrated using a fully systemized Chimera methodology for steady and unsteady problems. This methodology consist of a Chimera hole-cutting, a new cut-paste algorithm for optimal mesh. interface generation and a two-step search method for donor cell identification. It is fully automated and requires minimal user input. All procedures of the Chimera technique are parallelized on the Cray T3E using the MPI library. Two and three-dimensional examples are chosen to demonstate the effectiveness and parallel performance of this procedure.

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CHIMERA 격자기법을 이용한 고속전철 주위의 전산유동해석 (Numerical Flow Simulations Around High Speed Train Using CHIMERA Grid Technique)

  • 최성욱;김인선
    • 한국전산유체공학회지
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    • 제1권1호
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    • pp.81-87
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    • 1996
  • The aerodynamic charateristics of high speed train can be improved by well-designing of its fore-body shape. In this paper, as a way of the design a fore-body shape which has optimal aerodynamic charasteristics, 9 models of fore-body shapes are proposed and the change of aerodynamic charateristics is studied through calculations of flow field around high speed train for each fore-body shape. The flow field around high speed trains are calculated using Thin-Layer Navier-Stokes equation and Chimera grid technique. The application of Chimera grid technique to these flow calculations over high speed train which has ground plane under the train makes grid generation easily. As a computaional algorithm, Pulliam and Chaussee's Diagonal algorithm, the modified form of the Beam and Warming's AF scheme which operates on block-tridiagonal matrices, is selected to reduce computaional time. Introducing hole points flag concept to this Diagonal algorithm. a algorithm for Chimera grid is generated. The variational trends of aerodynamic characteristics are studied from the results of flow calculations around high speed trains for 9 fore-body shapes.

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Characteristics of 'Hongrou Taoye', a Grafted Chimera in Sweet Orange and Satsuma Mandarin

  • Zhang, Min;Xie, Zongzhou;Deng, Xiuxin;Liao, Shengcai;Song, Wenhua;Tan, Yong
    • 원예과학기술지
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    • 제33권3호
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    • pp.390-395
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    • 2015
  • The synthesis of chimeras is a breeding approach for horticultural crops. In our breeding program, a new diploid citrus chimera, named 'Hongrou Taoye' (Citrus sinensis [L.] Osbeck + Citrus unshiu Marc.), was found arising at the junction where a 'Taoye' sweet orange (C. sinensis) scion was grafted onto Satsuma mandarin (C. unshiu). As an artificial chimera, its fruit traits derived from the L1 cell layer, with juice color and carotenoid complement, in which ${\beta}$-cryptoxanthin accumulated predominantly, similar to those of Satsuma mandarin. By contrast, traits originating from the L2/L3 cell layer, including pollen, seed, and rind aroma characteristics, were the same as those of 'Taoye' sweet orange (the scion). SSR and cpSSR analyses showed that both nuclear and chloroplast genomes of the chimera were a combination of both donor parents. 'Hongrou Taoye' thus combined the valuable traits of both donor plants, and therefore has good potential in citrus fresh market.

병렬화된 Chimera 격자 기법을 이용한 다단 로켓의 단분리 운동 해석 (Numerical Analysis on Separation Dynamics of Multi-stage Rocket System Using Parallelized Chimera Grid Scheme)

  • 고순흠;최성진;김종암;노오현;박정주
    • 한국전산유체공학회:학술대회논문집
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    • 한국전산유체공학회 2002년도 춘계 학술대회논문집
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    • pp.47-52
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    • 2002
  • The supersonic flow around multi-stage rocket system is analyzed using 3-D compressible unsteady flow solver. A Chimera overset grid technique is used for the calculation of present configuration and grid around the core rocket is composed of 3 zones to represent fins in the core rocket. Flow solver is parallelized to reduce the computation time, and an efficient parallelization algorithm for Chimera grid technique is proposed. AUSMPW+ scheme is used for the spatial discretization and LU-SGS for the time integration. The flow field around multi-stage rocket was analyzed using this developed solver, and the results were compared with that of a sequential solver The speed-up ratio and the efficiency were measured in several processors. As a result, the computing speed with 12 processors was about 10 times faster than that of a sequential solver. Developed flow solver is used to predict the trajectory of booster in separation stage. From the analyses, booster collides against core rocket in free separation case. So, additional jettisoning forces and moments needed for a safe separation are examined.

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장착하중 예측을 통한 UMSAPv에 적용된 중첩 격자 기법 검증 (Validation of Chimera Grid Method Applied to UMSAPv With Prediction of Carriage Load)

  • 강선욱;안계현;이승수
    • 한국항공우주학회지
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    • 제50권10호
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    • pp.669-676
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    • 2022
  • 본 논문에서는 비정렬 CFD 해석자 UMSAPv에 적용된 중첩 격자 기법의 검증을 위하여 항공기에 장착된 store의 장착하중을 구하였다. 먼저, 잘 알려진 Eglin Wing/Pylon/Finned store 문제에 대해 UMSAPv의 중첩 격자 기법을 검증하였다. 다음으로 F/A-18C clean 형상에서 대하여 받음각에 따른 아음속 유동해석을 수행하였다. 계산 결과를 정렬 CFD 해석자인 MSAPv을 사용한 선행연구결과와 비교하여 Umsapv의 해석능력을 검증하였다. 마지막으로 F/A-18C/JDAM의 장착하중은 중첩 격자와 단일 격자로 수행하였다. 계산된 결과는 다른 CFD결과, 실험 및 비행시험과 비교하였다.