• Title/Summary/Keyword: constraint

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균열선단 근방 변위측정 위치에 따른 구속효과 $A_{2}$ (Experimental Constraint Effect $A_{2}$, Values depending on Displacement according to measuring Positions near Crack Front.)

  • 한민수;장석기;이돈출;김성종
    • 대한기계학회:학술대회논문집
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    • 대한기계학회 2004년도 추계학술대회
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    • pp.25-30
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    • 2004
  • The magnitude of constraint effect $A_{2}$ values were experimentally estimated using displacement according to measuring positions on the non-linear elastic plastic fracture toughness estimate. For 25.4 mm thickness SS400 steel CT specimen, constraint effect $A_{2}$ values we re dependent on specimen configuration and on measured displacement near crack front. Commonly, Estimating constraint effect $A_{2}$ measuring position for displacement should be existed inside plastic region. Therefore, the ${\delta}_{5}$ method was not reliable for evaluation of constraint effect $A_{2}$ values because measuring position for displacement is in elastic region at crack growth initiation in this paper.

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APPLICATION OF CONSTRAINT LOGIC PROGRAMMING TO JOB SEQUENCING

  • Ko, Jesuk;Ku, Jaejung
    • 한국경영과학회:학술대회논문집
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    • 대한산업공학회/한국경영과학회 2000년도 춘계공동학술대회 논문집
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    • pp.617-620
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    • 2000
  • In this paper, we show an application of constraint logic programming to the operation scheduling on machines in a job shop. Constraint logic programming is a new genre of programming technique combining the declarative aspect of logic programming with the efficiency of constraint manipulation and solving mechanisms. Due to the latter feature, combinatorial search problems like scheduling may be resolved efficiently. In this study, the jobs that consist of a set of related operations are supposed to be constrained by precedence and resource availability. We also explore how the constraint solving mechanisms can be defined over a scheduling domain. Thus the scheduling approach presented here has two benefits: the flexibility that can be expected from an artificial intelligence tool by simplifying greatly the problem; and the efficiency that stems from the capability of constraint logic programming to manipulate constraints to prune the search space in an a priori manner.

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받침의 구속과 편기를 갖는 경사지게 설치된 PSCI빔의 안전성 평가 (Safety Evaluation for PSCI-Beam by Tilt-Constructed with Constraint and Deviation of Bearings)

  • 박창호;신재인;이병주;서상길
    • 한국콘크리트학회:학술대회논문집
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    • 한국콘크리트학회 2006년도 춘계학술발표회 논문집(I)
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    • pp.346-349
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    • 2006
  • Superstructure of reinforced concrete bridges are shortened or elongated due to creep, drying shrinkage, temperature and so on. Most of bridge superstructures are free to shortening and elongation without constraint and stresses will not be induced by creep, drying shrinkage and temperature. But if bridge superstructure are constraint due to wrong setting and functional defects of bridge bearing, very large constraint forces can be induced. In this study, PSCI-Beam by tilt-constructed with constraint and deviation of bearings are presented and the effects of time-dependent constraint stress and temperature loads are investigated.

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제약 조건 만족과 불확실한 지식의 처리 (Constraint Satisfaction and Uncertain Knowledge)

  • 신양규
    • Journal of the Korean Data and Information Science Society
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    • 제6권2호
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    • pp.17-27
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    • 1995
  • 제약 조건 만족의 관점에서 불확실한 지식을 표현하고 처리하는 방법을 제안하였다. 등식이나 부등식은 만족되어야 할 제약 조건들이며, 제약 조건들은 수리 논리식으로 표현될 수 있는데 이들은 주어진 수리 논리식들의 집합에 대한 만족성을 계산하는 제약 조건 해결 프로그램에 의해 답을 얻을 수 있다. 불확실성을 포함한 규칙 기반 시스템들은 확률론의 초보적인 내용을 응용하여 표현되는데, 이 경우 제약 조건 해결 프로그램으로 효율적인 결과를 얻을 수 있다.

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Optical Flow 추정을 위한 Fuzzy constraint Line Clustering에 관한 연구 (A study on fuzzy constraint line clustering for optical flow estimation)

  • 김현주;강해석;이상홍;김문현
    • 전자공학회논문지B
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    • 제31B권9호
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    • pp.150-158
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    • 1994
  • In this paepr, Fuzzy Constraint Line Clustering (FCLC) method for optical flow estimation is proposed. FCLC represents the spatical and temporal gradients as fuzzy sets. Based on these sets, several constraint lines with different membership values are generated for the poxed whose velocity is to be estimated. We describe the process for obtaining the membership values of the spatial and temporal gradients and that of the corresponding constraint line. We also show the process for deciding the tightest cluster of point formalated by intersection between constraint lines. For the synthetic and real images, the results of FCLC are compared with of CLC.

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부등호 제약조건의 등호제약조건화를 통한 OPF해석 알고리즘 (OPF Algorithm of changing inequality constraint to equality constraint)

  • 최장흠;김건중;전동훈;임종호;이병일;한현규
    • 대한전기학회:학술대회논문집
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    • 대한전기학회 1999년도 추계학술대회 논문집 학회본부 A
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    • pp.197-199
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    • 1999
  • This paper deals with optimal power flow, which is optimal problem with equality constraint and inequality constraint. A algorithm of changing two constraints problem to one constraint - equality constraint problem - that make it analytical access for optimal power flow is presented.

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구속조건의 가용성을 보장하는 신경망기반 근사최적설계 (BPN Based Approximate Optimization for Constraint Feasibility)

  • 이종수;정희석;곽노성
    • 한국전산구조공학회:학술대회논문집
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    • 한국전산구조공학회 2007년도 정기 학술대회 논문집
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    • pp.141-144
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    • 2007
  • Given a number of training data, a traditional BPN is normally trained by minimizing the absolute difference between target outputs and approximate outputs. When BPN is used as a meta-model for inequality constraint function, approximate optimal solutions are sometimes actually infeasible in a case where they are active at the constraint boundary. The paper describes the development of the efficient BPN based meta-model that enhances the constraint feasibility of approximate optimal solution. The modified BPN based meta-model is obtained by including the decision condition between lower/upper bounds of a constraint and an approximate value. The proposed approach is verified through a simple mathematical function and a ten-bar planar truss problem.

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A Geometric Constraint Solver for Parametric Modeling

  • Jae Yeol Lee;Kwangsoo Kim
    • 한국CDE학회논문집
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    • 제3권4호
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    • pp.211-222
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    • 1998
  • Parametric design is an important modeling paradigm in CAD/CAM applications, enabling efficient design modifications and variations. One of the major issues in parametric design is to develop a geometric constraint solver that can handle a large set of geometric configurations efficiently and robustly. In this appear, we propose a new approach to geometric constraint solving that employs a graph-based method to solve the ruler-and-compass constructible configurations and a numerical method to solve the ruler-and-compass non-constructible configurations, in a way that combines the advantages of both methods. The geometric constraint solving process consists of two phases: 1) planning phase and 2) execution phase. In the planning phase, a sequence of construction steps is generated by clustering the constrained geometric entities and reducing the constraint graph in sequence. in the execution phase, each construction step is evaluated to determine the geometric entities, using both approaches. By combining the advantages of the graph-based constructive approach with the universality of the numerical approach, the proposed approach can maximize the efficiency, robustness, and extensibility of geometric constraint solver.

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동시성공학 모형의 계층적 제약식 네트워크 표현 방법론 (Hierarchical Constraint Network Representation of Concurrent Engineering Models)

  • 김영호
    • 대한산업공학회지
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    • 제22권3호
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    • pp.427-440
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    • 1996
  • Constraint networks are a major approach to knowledge representation in Concurrent Engineering (CE) systems. The networks model various factors in CE as constraints linked by shared variables. Many systems have been developed to assist constraint network processing. While these systems can be useful, their underlying assumption that a solution must simultaneously satisfy all the constraints is often unrealistic and hard to achieve. Proposed in this paper is a hierarchical representation of constraint networks using priorities, namely Prioritized Constraint Network (PCN). A mechanism to propagate priorities is developed, and a new satisfiability definition taking into account the priorities is described. Strength of constraint supporters can be derived from the propagated priorities. Several properties useful for investigating PCN's and finding effective solving strategies ore developed.

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트랙좌표계를 이용한 철도차량의 동역학 해석에 관한 연구 (A Study on the Dynamic Analysis of Railway Vehicle by Using Track Coordinate System)

  • 강주석
    • 한국자동차공학회논문집
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    • 제21권2호
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    • pp.122-130
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    • 2013
  • Rail geometries such as cant, grade and curvature can be easily represented by means of a track coordinate system. In this analysis, in order to derive a dynamic and constraint equation of a wheelset, the track coordinate system is used as an intermediate stage. Dynamic and constraint equations of railway vehicle bodies except the wheelset are written in the Cartesian coordinate system as a conventional method. Therefore, whole dynamic equations of a railway vehicle are derived by combining wheelset dynamic equations and dynamic equations of railway vehicle bodies. Constraint equations and constraint Jacobians are newly derived for the track coordinate system. A process for numerical analysis is suggested for the derived dynamic and constraint equations of a railway vehicle. The proposed dynamic analysis of a railway vehicle is validated by comparison against results obtained from VI-RAIL analysis.