• Title/Summary/Keyword: Multiple constraints

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The Generalized Continuous Multiple-Choice Linear Knapsack Problem with Generalized Lower Bound Constraints (일반하한제약을 갖는 일반연속 다중선택 선형배낭문제의 해법연구)

  • 원중연
    • Journal of Korean Society of Industrial and Systems Engineering
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    • v.21 no.45
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    • pp.291-299
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    • 1998
  • We present a variant for the generalized continuous multiple-choice knapsack problem[1], which additionally has the well-known generalized lower bound constraints. The presented problem is characterized by some variables which only belong to the simple upper bound constraints and the others which are partitioned into both the continuous multiple-choice constraints and the generalized lower bound constraints. By exploiting some extended structural properties, an efficient algorithm of order Ο($n^2$1og n) is developed, where n is the total number of variables. A numerical example is presented.

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PARALLEL OPTIMAL CONTROL WITH MULTIPLE SHOOTING, CONSTRAINTS AGGREGATION AND ADJOINT METHODS

  • Jeon, Moon-Gu
    • Journal of applied mathematics & informatics
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    • v.19 no.1_2
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    • pp.215-229
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    • 2005
  • In this paper, constraint aggregation is combined with the adjoint and multiple shooting strategies for optimal control of differential algebraic equations (DAE) systems. The approach retains the inherent parallelism of the conventional multiple shooting method, while also being much more efficient for large scale problems. Constraint aggregation is employed to reduce the number of nonlinear continuity constraints in each multiple shooting interval, and its derivatives are computed by the adjoint DAE solver DASPKADJOINT together with ADIFOR and TAMC, the automatic differentiation software for forward and reverse mode, respectively. Numerical experiments demonstrate the effectiveness of the approach.

Optimal Period and Priority Assignment Using Task & Message-Based Scheduling in Distributed Control Systems (분산 제어 시스템에서의 태스크와 메시지 기반 스케줄링을 이용한 최적 주기와 우선순위 할당)

  • 김형육;이철민;박홍성
    • Journal of Institute of Control, Robotics and Systems
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    • v.8 no.6
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    • pp.506-513
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    • 2002
  • Distributed control systems(DCS) using fieldbus such as CAN have been applied to process systems but it is very difficult to design the DCS while guaranteeing the given end-to-end constraints such as precedence constraints, time constraints, and periods and priorities of tasks and messages. This paper presents a scheduling method to guarantee the given end-to-end constraints. The presented scheduling method is the integrated one considering both tasks executed in each node and messages transmitted via the network and is designed to be applied to a general DCS that has multiple loops with several types of constraints, where each loop consists of sensor nodes with multiple sensors, actuator nodes with multiple actuators and controller nodes with multiple tasks. An assignment method of the optimal period of each loop and a heuristic assignment rule of each message's priority are proposed and the integrated scheduling method is developed based on them.

End-to-End Scheduling Method Considering 3-type RT-Data in Distributed Control Systems (분산 제어시스템에서 3가지 형태의 실시간 데이터를 고려하는 양극단 스케줄링 방법)

  • Kim, Hyoung-Yuk;Park, Hong-Seong
    • Proceedings of the KIEE Conference
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    • 2003.11b
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    • pp.311-314
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    • 2003
  • In recent years, distributed control systems(DCS) using fieldbus such as CAN have been applied to process systems but it is very difficult to design the DCS while guaranteeing the given end-to-end constraints such as precedence constraints, time constraints, and periods and priorities of tasks and messages. This paper presents a scheduling method to guarantee the given end-to-end constraints considering aperiodic, periodic and non-real-time message and task simultaneously. The presented scheduling method is the integrated one considering both tasks executed in each node and messages transmitted via the network and is designed to be applied to a general DCS that has multiple loops with several types of constraints, where each loop consists of sensor nodes with multiple sensors, actuator nodes with multiple actuators and controller nodes with multiple tasks.

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Cooperative Localization for Multiple Mobile Robots using Constraints Propagation Techniques on Intervals (제약 전파 기법을 적용한 다중 이동 로봇의 상호 협동 위치 추정)

  • Jo, Kyoung-Hwan;Jang, Choul-Soo;Lee, Ji-Hong
    • Journal of Institute of Control, Robotics and Systems
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    • v.14 no.3
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    • pp.273-283
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    • 2008
  • This article describes a cooperative localization technique of multiple robots sharing position information of each robot. In case of conventional methods such as EKF, they need to linearization process. Consequently, they are not able to guarantee that their result is range containing true value. In this paper, we propose a method to merge the data of redundant sensors based on constraints propagation techniques on intervals. The proposed method has a merit guaranteeing true value. Especially, we apply the constraints propagation technique fusing wheel encoders, a gyro, and an inexpensive GPS receiver. In addition, we utilize the correlation between GPS data in common workspace to improve localization performance for multiple robots. Simulation results show that proposed method improve considerably localization performance of multiple robots.

A topology optimization method of multiple load cases and constraints based on element independent nodal density

  • Yi, Jijun;Rong, Jianhua;Zeng, Tao;Huang, X.
    • Structural Engineering and Mechanics
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    • v.45 no.6
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    • pp.759-777
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    • 2013
  • In this paper, a topology optimization method based on the element independent nodal density (EIND) is developed for continuum solids with multiple load cases and multiple constraints. The optimization problem is formulated ad minimizing the volume subject to displacement constraints. Nodal densities of the finite element mesh are used a the design variable. The nodal densities are interpolated into any point in the design domain by the Shepard interpolation scheme and the Heaviside function. Without using additional constraints (such ad the filtering technique), mesh-independent, checkerboard-free, distinct optimal topology can be obtained. Adopting the rational approximation for material properties (RAMP), the topology optimization procedure is implemented using a solid isotropic material with penalization (SIMP) method and a dual programming optimization algorithm. The computational efficiency is greatly improved by multithread parallel computing with OpenMP to run parallel programs for the shared-memory model of parallel computation. Finally, several examples are presented to demonstrate the effectiveness of the developed techniques.

An Efficient Algorithm for the Generalized Continuous Multiple Choice linear Knapsack Problem (일반연속 다중선택 선형배낭문제의 효율적인 해법연구)

  • Won, Joong-Yeon
    • Journal of Korean Institute of Industrial Engineers
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    • v.23 no.4
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    • pp.661-667
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    • 1997
  • We consider a generalized problem of the continuous multiple choice knapsack problem and study on the LP relaxation of the candidate problems which are generated in the branch and bound algorithm for solving the generalized problem. The LP relaxed candidate problem is called the generalized continuous multiple choice linear knapsack problem and characterized by some variables which are partitioned into continuous multiple choice constraints and the others which only belong to simple upper bound constraints. An efficient algorithm of order O($n^2logn$) is developed by exploiting some structural properties and applying binary search to ordered solution sets, where n is the total number of variables. A numerical example is presented.

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A Study on the Effect of Situational Constraints of Negotiation affects Outcomes: Focus on the Conditions of Trade Contracts (협상의 상황적 제약이 협상성과에 미치는 영향에 관한 연구 - 무역계약 상황을 중심으로 -)

  • Kim, Ji-Yong
    • International Commerce and Information Review
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    • v.11 no.2
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    • pp.329-342
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    • 2009
  • The purpose of this study was to identify the issues which how situational constraints of negotiation affect outcomes. To achieve the purpose of this research, a multiple regression model was set up to identify the relationships between situational constraints of negotiation and negotiation outcome on international trade contracts. To implement the study, empirical questionnaires were collected from Korean business men who have actually conducted international trade with foreign firms. Reliability analysis and factor analysis were used to assess the reliability and validity of research variables. and multiple regression analysis were used for testing the relationships between situational constraints of negotiation and negotiation outcome. From this study, following results were identified; i) situational constraints of negotiation effects on negotiation outcomes ii) arbitrary and continuous situations affect significantly positive on negotiation outcomes iii) submissive situations affect significantly negative effects on negotiation outcomes In conclusion, participant of negotiation and their managers try to promote negotiation situation toward to arbitrary and continuous situations if they have any availability.

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Using multiple point constraints in finite element analysis of two dimensional contact problems

  • Liu, C.H.;Cheng, I.;Tsai, An-Chi;Wang, Lo-Jung;Hsu, J.Y.
    • Structural Engineering and Mechanics
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    • v.36 no.1
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    • pp.95-110
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    • 2010
  • Two-dimensional elastic contact problems, including normal, tangential, and rolling contacts, are treated with the finite element method in this study. Stress boundary conditions and kinematic conditions are transformed into multiple point constraints for nodal displacements in the finite element method. Upon imposing these constraints into the finite element system equations, the calculated nodal stresses and nodal displacements satisfy stress and displacement contact conditions exactly. Frictional and frictionless contacts between elastically identical as well as elastically dissimilar materials are treated in this study. The contact lengths, sizes of slip and stick regions, the normal and the shear stresses can be found.

Bayesian Inference with Inequality Constraints (부등 제한 조건하에서의 베이지안 추론)

  • Oh, Man-Suk
    • The Korean Journal of Applied Statistics
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    • v.27 no.6
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    • pp.909-922
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    • 2014
  • This paper reviews Bayesian inference with inequality constraints. It focuses on ⅰ) comparison of models with various inequality/equality constraints on parameters, ⅱ) multiple tests on equalities of parameters when parameters are under inequality constraints, ⅲ) multiple test on equalities of score parameters in models for contingency tables with ordinal categorical variables.