• 한국조경학회지
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• 제28권1호
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• pp.29-36
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• 2000

Leisure constraints mean the factor to constrain individual's leisure activity. Leisure constraints are composed of interpersonal constraints, interpersonal constraints and structural constraints. The purposes of this study are to show that intrapersonal leisure constraints have a strong effect on leisure preference, and leisure constraints are sequential and hierachical process. Intrapersonal constraints effect on leisure constraints in first step. And then interpersonal constraints and structural constraints effect on leisure participation. Those three leisure constraints are all linked together and come out step by step. Regarding adults as a population, who are more than 20-year-old and live in Seoul, 9 dongs were chose after dividing into upper and lower classes according to the value of their residence. The questionnaire consists of 4 parts: intrapersonal constraints, interpersonal constraints, structural constraints, and demographic characteristics. Results of this paper is that people who have strong intrapersonal constraints normally have problems caused from social structure. Intrapersonal constraints and structural constrains come out not seperately but together. Then, it can be said that structural constraints have an influence over intrapersonal constraints. So, it's necessary to solve structural problems to increase preferences and participations of them.

• 산업공학
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• 제25권3호
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• pp.300-308
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• 2012

For convenient business process modeling we propose a mathematical approach to obtain appropriate process structures. In this paper, we define business process structural constraints, on which basis, using Social Network Analysis (SNA), we analyze the frequency of handover occurrences among performers in social network. We here present, therefrom, a new, mathematical approach to business process modeling that proceeds by identifying the social relations among activities.

• 한국전산구조공학회:학술대회논문집
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• 한국전산구조공학회 1997년도 가을 학술발표회 논문집
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• pp.189-196
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• 1997

The development of computer integrated systems for structural design requires models to describe and organize information and activities involved in design. An entity-based integrated design model involves a number of product and process entities. Product entities and process entities describe design information and design activities, respectively. One type of relationships among entities is interaction relationships, which describe interdependencies among design information. The interaction relationships can be represented as constraints. Types of constraints include demand constraints, dependency constraints, and interaction constraints. The concepts of representing and processing demand constraints in an entity-based integrated design model are presented.

• 한국전산구조공학회:학술대회논문집
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• 한국전산구조공학회 1998년도 봄 학술발표회 논문집
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• pp.191-198
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• 1998

An entity-based integrated design model can be used to organize and represent information and activities involved in design. The model involves a number of product and process entities. Product entities describe design information, and process entities describe design activities. The relationships among entities Includes organizational, interaction, and sequence relationships. The paper focuses interaction relationships among design information. The interaction relationships can be represented as constraints. Types of constraints includes demand constraints, dependency constraints, and interaction constraints. The paper describes dependency and Interaction constraints. The concepts of representing and processing dependency and interaction constraints in an entity-based integrated design model are presented.

• 한국전산구조공학회:학술대회논문집
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• 한국전산구조공학회 1995년도 가을 학술발표회 논문집
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• pp.1-8
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• 1995

This work presents a new method to deal with buckling constraints. The mathematical optimization process of truss structures proposed earlier by the author has been proved to be the most rigorous method. The inclusion of buckling constraints, however, gives rise to a new problem The allowable compression stress of a member changes from one design iteration to another. This changing stress limit creates a good deal of noise in selecting active constraints and makes the solution process unstable. This problem can be overcome by introducing relaxation parameters. This work, however, aims at establishing a more rigorous method by containing the allowable compression stress in the left hand side of the associated constraint.

• Structural Engineering and Mechanics
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• 제62권3호
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• pp.297-302
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• 2017

Structural reanalysis is frequently utilized to reduce the computational cost so that the process of design or optimization can be accelerated. The supports can be regarded as the design variables and may be modified in various types of structural optimization problems. The location, number, and type of supports can make a great impact on the performance of the structure. This paper presents a unified method for structural static reanalysis with imposition or relaxation of some support constraints. The information from the initial analysis has been fully utilized and the computational time can be significantly reduced. Numerical examples are used to validate the effectiveness of the proposed method.

• Structural Engineering and Mechanics
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• 제7권3호
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• pp.241-257
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• 1999

This paper presents a procedure to minimize the cost of materials of cable-stayed bridges with composite box girder and concrete tower. Two sets of iterations are included in the proposed procedure. The first set of iteration performs the structural analysis for a cable-stayed bridge. The second set of iteration performs the optimization process. The design is formulated as a general mathematical problem with the cost of the bridge as the objective function and bending forces, shear forces, fatigue stresses, buckling and deflection as constraints. The constraints are developed based on the Canadian National Standard CAN/CSA-S6-88. The finite element method is employed to perform the complicated nonlinear structural analysis of the cable-stayed bridges. The internal penalty function method is used in the optimization process. The limit states design method is used to determine the load capacity of the bridge. A computer program written in FORTRAN 77 is developed and its validity is verified by several practical-sized designs.

• Structural Engineering and Mechanics
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• 제43권3호
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• pp.273-285
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• 2012

Structural reanalysis is frequently used to reduce the computational cost during the process of design or optimization. The supports can be regarded as the design variables in various types of structural optimization problems. The location, number, and type of supports may be varied in order to yield a more effective design. The paper is focused on structural static reanalysis problem with added supports where some node displacements along axes of the global coordinate system are specified. A new approach is proposed and exact solutions can be provided by the approach. Thus, it belongs to the direct reanalysis methods. The information from the initial analysis has been fully exploited. Numerical examples show that the exact results can be achieved and the computational time can be significantly reduced by the proposed method.

• Structural Engineering and Mechanics
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• 제17권3_4호
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• pp.593-609
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• 2004

Peak response is a more suitable index than mean response in the light of structural safety. In this study, a controller optimization method is proposed to restrict peak responses of building structures subject to earthquake excitations, which are modeled as partially stationary stochastic process. The constraints are given with specified failure probabilities of peak responses. LQR is chosen to assure stability in numerical process of optimization. Optimization problem is formulated with weightings on controlled outputs as design variables and gradients of objective and constraint functions are derived. Full state feedback controllers designed by the proposed method satisfy various design objectives and output feedback controllers using LQG also yield similar results without significant performance deterioration.

• Structural Engineering and Mechanics
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• 제52권6호
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• pp.1121-1134
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• 2014

Structural design is usually an optimization process. Numerous parameters such as the member shapes and sizes, the elasticity modulus of material, the locations of nodes and the support constraints can be selected as design variables. These variables are progressively revised in order to obtain a satisfactory structure. Each modification requires a fresh analysis for the displacements and stresses, and reanalysis can be employed to reduce the computational cost. This paper is focused on static reanalysis problem with modification of deleting some supports. An efficient reanalysis method is proposed. The method makes full use of the initial information and preserves the ease of implementation. Numerical examples show that the calculated results of the proposed method are the identical as those of the direct analysis, while the computational time is remarkably reduced.