• 제목/요약/키워드: Mixed approach

검색결과 887건 처리시간 0.031초

비선형 유한요소법에 의한 탄성받침의 이차원 해석 (2 Dimensional Nonlinear Finite Element Analysis for Layered Elastomeric Bearings)

  • 박문호;김진규;이성준
    • 한국산업융합학회 논문집
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    • 제3권4호
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    • pp.329-336
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    • 2000
  • A geometric and material nonlinear finite element analysis is developed for the layered elastomeric bearings. In this study, a mixed variational approach with separate variables is used to describe the displacement and volume change of rubber. To represent finely deformed behavior, Kirchoff stress tensors are used and converted Eulerian stress tensors to describe real physical meanings. Newton's method is utilized to solve the governing nonlinear finite element equations. Numerical test are performed in the case of compression and shear to verify the theory and to illustrate the application of this analysis. And the results of this study were compared to the results of Moore's discrete finite element analysis.

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다자게임에서 발전력제약이 복합전략 내쉬균형에 미치는 영향 (Effect of Generation Capacity Constraints on a Mixed Strategy Nash Equilibrium in a Multi-Player Game)

  • 이광호
    • 전기학회논문지
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    • 제57권1호
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    • pp.34-39
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    • 2008
  • Nash Equilibrium(NE) is essential to investigate a participant's bidding strategy in a competitive electricity market. Congestion on a transmission line makes it difficult to compute the NE due to causing a mixed strategy. In order to compute the NE of a multi-player game, some heuristics are proposed with concepts of a key player and power transfer distribution factor in other studies. However, generation capacity constraints are not considered and make it more difficult to compute the NE in the heuristics approach. This paper addresses an effect of generation capacity limits on the NE, and suggest a solution technique for the mixed strategy NE including generation capacity constraints as two heuristic rules. It is reported in this paper that a role of the key player who controls congestion in a NE can be transferred to other player depending on the generation capacity of the key player. The suggested heuristic rules are verified to compute the mixed strategy NE with a consideration of generation capacity constraints, and the effect of the generation constraints on the mixed strategy NE is analyzed in simulations of IEEE 30 bus systems.

Enhancing CO2/CH4 separation performance and mechanical strength of mixed-matrix membrane via combined use of graphene oxide and ZIF-8

  • Li, Wen;Samarasinghe, S.A.S.C.;Bae, Tae-Hyun
    • Journal of Industrial and Engineering Chemistry
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    • 제67권
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    • pp.156-163
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    • 2018
  • High-performance mixed-matrix membranes that comprise both zeolitic imidazolate framework-8 (ZIF-8) and graphene oxide (GO) were synthesized with a solution casting technique to realize excellent $CO_2/CH_4$ separation. The incorporation of ZIF-8 nanocrystals alone in ODPA-TMPDA polyimide can be used to significantly enhance $CO_2$ permeability compared with that of pure ODPA-TMPDA. Meanwhile, the addition of a GO nanostack alone in ODPA-TMPDA contributes to improved $CO_2/CH_4$ selectivity. Hence, a composite membrane that contains both fillers displays significant enhancements in $CO_2$ permeability (up to 60%) and $CO_2/CH_4$ selectivity (up to 28%) compared with those of pure polymeric membrane. Furthermore, in contrast to the ZIF-8 mixed-matrix membrane, which showed decreased mechanical stability, it was found that the incorporation of GO could improve the mechanical strength of mixed-matrix membranes. Overall, the synergistic effects of the use of both fillers together are successfully demonstrated in this paper. Such significant improvements in the mixed-matrix membrane's $CO_2/CH_4$ separation performance and mechanical strength suggest a feasible and effective approach for potential biogas upgrading and natural gas purification.

다중 혼합기 난류 비예혼합 연소시스템에 대한 수치모델링 (Two Conserved Scalar Approach for the Turbulent Nonpremixed Flames)

  • 김군홍;강성모;김용모;안국영
    • 한국연소학회:학술대회논문집
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    • 대한연소학회 2003년도 제27회 KOSCO SYMPOSIUM 논문집
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    • pp.57-61
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    • 2003
  • In the combustion modeling of non-premixed flames, the mixture fraction conserved scalar approach is widely utilized because reactants are mixed at the molecular level before burning and atomic elements are conserved in chemical reactions. In the mixture fraction approach, combustion process is simplified to a mixing problem and the interaction between chemistry and turbulence could be modelled by many sophisticated combustion models including the flamelet model and CMC. However, most of the mixture fraction approach is restricted to one mixture system. In this study, the flamelet model based on the two-feed system is extended to the multiple fuel-feeding systems by the two mixture fraction conserved scalar approach.

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혼합이진정수목표계획법(混合二進整数目標計劃法)을 이용(利用)한 다수목표(多数目標)의 설비입지선정(設備立地選定) 및 해당문제(該當問題)에 관(関)한 연구(硏究) (A Mixed Zero-One Integer Goal programming Approach to Facility Location-Allocation Problem with Multiple Objectives)

  • 강인선;윤덕균
    • 대한산업공학회지
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    • 제10권2호
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    • pp.45-50
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    • 1984
  • This paper is concerned with the facility location-allocation problem (FLAP) with multiple objectives. A branch-and-bound procedure is presented to solve the mixed zero-one integer goal programming problem which is to determine facility locations from given candidate locations and to allocate facility capacity to given customer markets simultaneously. A numercial example is given to illustrate this procedure.

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준비시간이 있는 혼합모델 조립라인의 제품투입순서 결정 : Tabu Search 기법 적용 (Sequencing in Mixed Model Assembly Lines with Setup Time : A Tabu Search Approach)

  • 김여근;현철주
    • 경영과학
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    • 제13권1호
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    • pp.13-27
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    • 1996
  • This paper considers the sequencing problem in mixed model assembly lines with hybrid workstation types and sequence-dependent setup times. Computation time is often a critical factor in choosing a method of determining the sequence. We develop a mathematical formulation of the problem to minimize the overall length of a line, and present a tabu search technique which can provide a near optimal solution in real time. The proposed technique is compared with a genetic algorithm and a branch-and-bound method. Experimental results are reported to demonstrate the efficiency of the technique.

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혼합주도 협력을 위한 상호 스크립트 접근 방법 (Joint Script Approach for Mixed-initiative Collaboration)

  • 강동엽;최호진
    • 한국정보처리학회:학술대회논문집
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    • 한국정보처리학회 2007년도 춘계학술발표대회
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    • pp.453-456
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    • 2007
  • 노인 복지 환경에서 혼합주도 협력(mixed-initiative collaboration)이 가능한 로봇의 지능 개발이 본 연구의 궁극적인 목표이다. 본 논문에서는 다양한 담화(discourse)으로부터 협력 과정들을 분석하여 상호 주도 협력을 위한 이슈들을 찾아내고, 이러한 주요 요소를 바탕으로 상대 인지시스템의 사용자 모델(user model)을 포함할 수 있는 상호 스크립트 모형(joint script model)을 제안하고 이를 이용한 로봇 계획법(robot planning)의 방법론과 실험에 대한 접근법을 제시한다.

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