• Title, Summary, Keyword: Constraint

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CBAbench: An AutoCAD-based Dynamic Geometric Constraint System

  • Gong, Xiong;Wang, Bo-Xing;Chen, Li-Ping
    • International Journal of CAD/CAM
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    • v.6 no.1
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    • pp.173-181
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    • 2006
  • In this paper, an integration framework of Geometric Constraint Solving Engine and AutoCAD is presented, and a dynamic geometric constraint system is introduced. According to inherent orientation features of geometric entities and various Object Snap results of AutoCAD, the' proposed system can automatically construct an under-constrained geometric constraint model during interactive drawing. And then the directed constraint graph in a geometric constraint model is realtime modified in order to produce an optimal constraint solving sequence. Due to the open object-oriented characteristics of AutoCAD, a set of user-defined entities including basic geometric elements and graphics constraint relations are defined through derivation. And the custom-made Object Reactor and Command Reactor are also constructed. Several powerful characteristics are achieved based on these user-defined entities and reactors, including synchronously processing geometric constraint information while saving and opening DWG files, visual constraint relations, and full adaptability to Undo/Redo operations. These characteristics of the proposed system can help the designers more easily manage geometric entities and constraint relations between them.

Constraint Satisfaction Algorithm in Constraint Network using Simulated Annealing Method (Simulated Annealing을 이용한 제약 네트워크에서의 제약 충족방식에 관한 연구)

  • 차주헌;이인호;김재정
    • Proceedings of the Korean Society of Precision Engineering Conference
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    • pp.589-594
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    • 1997
  • We have already presented the constraint satisfaction algorithm which could solve the losed loop problem in constraint network by using local constraint propagation, variable elimination and constraint modularization. With this algorithm, we have implemented a knowledge-based system (intelligent CAD) for supporting machine design interactively. In this paper, we present newer constraint satisfaction algorithm which can solve inequalities or under-constrained problems in constraint network, interactively and efficiently. This algorithm is a hybrid type of using both declarative description (constraint represention) and optimization algorithm (Simulated Annealing), simultaneously. The under-constrained problems are represented by constraint networks and satisfied completely with this algorithm. The usefulness of our algorithm will be illustrated by the application to a gear design.

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Constraint Data Modeling for Spatiotemporal Data Application (시공간 데이터 응용을 위한 제약 데이터 모델링)

  • Jung, Hun Jo;Woo, Sung Koo
    • Journal of the Korea Society of Digital Industry and Information Management
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    • v.6 no.4
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    • pp.45-56
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    • 2010
  • This paper suggests constraint data modeling based on constraint data presentation techniques to perform complex spatial database operation naturally. We were able to identify the limitation of extendibility of dimension and non-equal framework via relevant research for former schema of spatial database and query processing. Therefore we described generalized tuple of spatial data and the definition of suggested constraint data modeling. Also we selected MLPQ/PReSTO tool among constraint database prototype and compare standard functionality of ARC/VIEW. Then we design scenario for spatial operation using MLPQ/PReSTO and we suggested application effect after query processing. Based on above explanation, we were able to identify that we can process spatial data naturally and effectively using simple constraint routine on same framework via constraint data modeling.

Analysis and Evaluation for Constraint Enforcement System (제한 시스템의 분석 및 평가)

  • Hong, Min;Park, Doo-Soon;Choi, Yoo-Joo
    • Journal of the Korea Society for Simulation
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    • v.18 no.2
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    • pp.57-64
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    • 2009
  • Stable and effective constraint enforcement system is one of the crucial components for physically-based dynamic simulations. This paper presents analysis and evaluation for traditional constraint enforcement systems(Lagrange Multiplier method, Baumgarte stabilization method, Post-stabilization method, Implicit constraint enforcement method, Fast projection method) to provide a guideline to users who need to integrate a suitable constraint enforcement system into their dynamic simulations. The mathematical formulations for traditional constraint enforcement systems are presented in this paper. This paper describes a summary of evaluation which consists of constraint error comparison, computational cost, and dynamic behavior analysis to verify the efficiency of each traditional constraint enforcement system.

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Energy constraint control in numerical simulation of constrained dynamic system

  • 윤석준
    • 제어로봇시스템학회:학술대회논문집
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    • pp.376-382
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    • 1991
  • In the analysis of constrained holonomic systems, the Lagange multiplier method yields a system of second-order ordinary differential equations of motion and algebraic constraint equations. Conventional holonomic or nonholonomic constraints are defined as geometric constraints in this paper. Previous works concentrate on the geometric constraints. However, if the total energy of a dynamic system can be computed from the initial energy plus the time integral of the energy input rate due to external or internal forces, then the total energy can be artificially treated as a constraint. The violation of the total energy constraint due to numerical errors can be used as information to control these errors. It is a necessary condition for accurate simulation that both geometric and energy constraints be satisfied. When geometric constraint control is combined with energy constraint control, numerical simulation of a constrained dynamic system becomes more accurate. A new convenient and effective method to implement energy constraint control in numerical simulation is developed based on the geometric interpretation of the relation between constraints in the phase space. Several combinations of energy constraint control with either Baumgarte's Constraint Violation Stabilization Method (CVSM) are also addressed.

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The Effect of Leisure Constraint on Leisure Attitude of Workers (직장인들의 여가제약이 여가태도에 미치는 영향)

  • Yoon So-Young;Moon Sook-Jae;Yoo Soo-Hyun
    • Korean Family Resource Management Association
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    • v.9 no.1
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    • pp.59-73
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    • 2005
  • The purpose of this study was to understand which factors affect on the leisure constraint and leisure attitude of workers, to observe how the factors of leisure constraints affect on the leisure attitude. The subjects of this study were 267 urban workers who are older than 20 years old and resident in Seoul. The periods of this study was from November 15 to December 5. The modified versions of leisure constraint scale and leisure attitude scale were utilized for this study. The results of this study are as follows : First, as a result to compare the average of leisure constraint factors, intrapersonal constraint, which are individual mental status as interest, self-consciousness, uneasiness et at., was founded generally less than interpersonal constraints as personal relationship for leisure activity, or structural constraints as financial, time, information et at., Secondly, it was found that interpersonal constraint was statistically different in age, and that structural constraint was statistically different in sex, education, health status, marital status, income, and career. Thirdly, there were statistically different in cognitive leisure attitude, feeling leisure attitude, and behavioral leisure attitude according to the average monthly income and career. But, it was found that marital status and the five-day workweek system were not statistically different in 3 leisure attitude factors. Finally, 3 leisure constraint factors(intrapersonal, interpersonal, structural) had statistically significant effect on cognitive leisure attitude. Also, intrapersonal leisure constraint and interpersonal leisure constraint had statistically significant effect on feeling leisure attitude and behavioral leisure attitude

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Efficient Spatial Query Processing in Constraint Databases (제약 데이터베이스에서의 효율적인 공간질의 처리)

  • Woo, Sung-Koo;Ryu, Keun-Ho
    • Journal of Korea Spatial Information System Society
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    • v.11 no.1
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    • pp.79-86
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    • 2009
  • The tuple of constraint database consists of constraint logical formula and it could process the presentation and query of the constraint database simply. Query operation processing shall include the constraint formula between related tuple such as selection, union, intersection of spatial data through the constraint database. However, this could produce the increasing of duplicated or unnecessary data. Hence, it will drive up the cost as per quality. This paper identified problems regarding query processing result in the constraint database. Also this paper suggested the tuple minimization summary method for result relation and analyzed the effects for efficient query processing. We were able to identify that the effectiveness of the query processing was enhanced by eliminating unnecessary constraint formula of constraint relation using the tuple minimization method.

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A Study on the Residual Stress Distribution of Pure Titanium Welding Material (순수티타늄 용접재의 잔류응력분포에 관한 연구)

  • 최병기;권택용
    • Proceedings of the Korean Society of Machine Tool Engineers Conference
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    • pp.70-75
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    • 2002
  • It is generally applied constraint welding condition to structure manufacture in the industry field. But it is thinkable that the residual stress of the construction and specimens for experiment is different because not constraint welding but non-constraint welding are applied for experiment. To apply the constraint welding condition as the industry field and compare and evaluate the welding residual stress distribution, the TlG welding of the pure titanium was carried out under constraint and non-constraint welding conditions

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

  • Choi, J.H.;Kim, K.J.;Jeon, D.H.;Rhim, C.H.;Lee, B.R.;Han, H.G.
    • Proceedings of the KIEE Conference
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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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A Formulation of the Differential Equation on the Equations of Motion and Dynamic Analysis for the Constrained Multibody Systems (구속된 다물체 시스템에 대한 운동 방정식의 미분 방정식화 및 동역학 해석)

  • 이동찬;이상호;한창수
    • Transactions of the Korean Society of Automotive Engineers
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    • v.5 no.1
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    • pp.154-161
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    • 1997
  • This paper presents the method to eliminate the constraint reaction in the Lagrange multiplier form equation of motion by using a generalized coordinate driveder from the velocity constraint equation. This method introduces a matrix method by considering the m dimensional space spanned by the rows of the constraint jacobian matrix. The orthogonal vectors defining the constraint manifold are projected to null vectors by the tangential vectors defined on the constraint manifold. Therefore the orthogonal projection matrix is defined by the tangential vectors. For correcting the generalized position coordinate, the optimization problem is formulated. And this correction process is analyzed by the quasi Newton method. Finally this method is verified through 3 dimensional vehicle model.

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