• 대한전기학회논문지:전력기술부문A
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• 제55권11호
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• pp.447-452
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• 2006

This paper presents a scheme to solve the congestion problem with phase-shifting transformer(PST) controls and power generation controls using linear programming method. A good design of PST and power generation control can improve total transfer capability(TTC) in interconnected systems. This paper deals with an application of optimization technique for TTC calculation. Linear programming method is used to maximize power flow of tie line subject to security constraints such as voltage magnitude and real power flow in interconnected systems. The results are compared with that of repeat power flow(RPF) and sequential quadratic programming(SQP). The proposed method is applied to 10 machines 39 buses model systems to show its effectiveness.

• Communications for Statistical Applications and Methods
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• 제8권3호
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• pp.719-729
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• 2001

Overlap Maximization is a sampling technique to reduce survey costs and costs associated with the survey. It was first studied by Keyfitz(1951). Ernst(1998) presented a remarkable procedure for maximizing the overlap when the sampling units can be selected for two identical stratified designs simultaneously, But the approach involves mimicking the behaviour of nonlinear function by linear function and so it is less direct, even though the stratification problem for the overlap corresponds directly to the linear programming problem. furthermore, it uses the controlled selection algorithm that repeatedly needs zero-restricted controlled roundings, which are solutions of capacitated transportation problems. In this paper we suggest a comparatively simple procedure to use linear programming in order to maximize the overlap. We show how this procedure can be implemented practically.

• 대한전기학회:학술대회논문집
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• 대한전기학회 2001년도 하계학술대회 논문집 B
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• pp.590-592
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• 2001

We introduce a technique for designing homogeneous magnets using linear programming. The method has several advantages over existing techniques including: it allows complete flexibility in arbitrary geometric constraints on both the coil locations and the shape of the homogeneous volume; it guarantees a globally optimal solution, and it automatically choose the minimum number of coils necessary for the constraints.

• ETRI Journal
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• 제6권4호
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• pp.31-36
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• 1984

This paper presents an efficient method for real power loss minimization and for improvements in voltage profiles. This method is accomplished by optimal control of reactive power in the system. The problem is formulated as an optimization problem, suitable for solution by linear programming technique. After establishing the objective function for minimizing the system losses with the help of linearised sensitivity relationships of control variables, i. e., the transformer tap position, generator terminal voltages and switchable reactive power sources. The linear programming technique is used to determine the optimal adjustments to the above variables, simultaneously satisfying the constraints. The proposed algorithm has been tested on a sample system and the result is presented and discussed.

• 전기학회논문지
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• 제59권6호
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• pp.1059-1063
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• 2010

Shimming is an important technique in development of nuclear magnetic resonance (NMR) magnets where image resolution is highly dependent on magnetic field homogeneity. Classically, shimming may be categorized into two types: 1) active shimming that incorporates with extra coils and precise tuning of their currents; and 2)passive shimming that incorporates with pieces of steel placed in a bore of a main magnet and their uniform magnetization under homogeneous external fields. Additional magnetic fields, produced by the coils and/or the steel sheets, compensate original magnetic field from the main magnet in such a way that the total field becomes more homogeneous. In this paper, we developed a passive shimming method based on linear programming optimization. Linear programming is well known to be highly efficient to find a global minimum in various linear problems. We firstly confirmed the linearity of magnetization of ferromagnetic pieces under a presence of external magnetic fields. Then, we adopted the linear programming to find optimized allocation of the steel pieces in the inner bore of a main magnet to improve field homogeneity.

• 대한전기학회논문지:전력기술부문A
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• 제48권9호
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• pp.1167-1174
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• 1999

In this paper, we present a new technique for the local decomposition of convex structuring elements for morphological image processing. Local decomposition of a structuring element consists of local structuring elements, in which each structuring element consists of a subset of origin pixel and its eight neighbors. Generally, local decomposition of a structuring element reduces the amount of computation required for morphological operations with the structuring element. A unique feature of our approach is the use of linear integer programming technique to determine optimal local decomposition that guarantees the minimal amount of computation. We defined a digital convex polygon, which, in turn, is defined as a convex structuring element, and formulated the necessary and sufficient conditions to decompose a digital convex polygon into a set of basis digital convex polygons. We used a set of linear equations to represent the relationships between the edges and the positions of the original convex polygon, and those of the basis convex polygons. Further. a cost function was used represent the total processing time required for computation of dilation/erosion with the structuring elements in a decomposition. Then integer linear programming was used to seek an optimal local decomposition, that satisfies the linear equations and simultaneously minimize the cost function.

• 정보처리학회논문지D
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• 제17D권5호
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• pp.337-346
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• 2010

Timing diagram은 시간에 따른 시스템의 행동을 표현하기 용이하고 표현된 행동을 쉽게 인식할 수 있는다는 장점 때문에 널리 사용되고 있다. Timing diagram으로 기술된 시스템을 테스트 하기 위해서는 여러 기술이 필요하다. 그 중의 하나는 테스트 케이스 목표들이 존재할 때, 시스템 모델이 원하는 상태에 도달하도록 하기 위해 입력 값들의 시퀀스를 생성하는 기술이다. 본 논문은 Timing diagram모델에 대한 테스트 케이스 목표로부터 테스트 입력 시퀀스를 자동으로 생성하는 방법을 제안한다. Timing diagram에서 테스트 입력 시퀀스를 자동으로 생성하기 위해서는 입력 waveform과 시간 제약으로 이루어진 시점의 전이 조건을 만족시키는 적절한 입력 집합을 필요로 한다. 이와 같은 문제를 해결하기 위해, 본 논문에서는 선형 계획법을 이용한 접근 방식을 택하였는데, 해결과정은 다음과 같다. 1) Timing diagram 모델을 입력으로 받아 이를 선형 계획 문제로 변형한다. 2)변형된 선형 계획 문제를 선형 문제 해결 도구를 사용하여 해결한다. 3) 선형 계획 문제의 해답으로부터 Timing diagram모델의 테스트 입력 시퀀스를 생성한다. 본 논문에서는 임의의 Timing diagram 모델에 대해 이를 선형 계획법으로 모델링 하는 방법을 형식적으로 기술하였고, 증명을 통해 본 논문의 접근 방법의 타당성을 보였으며, 또한 도구를 구현하여 Timing diagram 예제 모델로부터 테스트 입력 시퀀스를 생성함으로써 본 논문의 유용성을 입증하였다.

• 제어로봇시스템학회논문지
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• 제5권3호
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• pp.249-256
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• 1999

The conventional robot manipulability is decomposed into linear manipulability and angular manipulability so that they may be analysed and visualized in easy way even in the case of 3 dimensional task space with 6 variables. After the Jacobian matrix is decomposed into linear part and angular part, constraint on joint velocities is transformed into linear task velocity and angular task velocity through the decomposed Jacobian matrices. Under the assumption of redundant robot manipulators, several optimization problems which utilize the redundancy are formulated to be solved by linear programming technique or sequential quadratic programming technique. After deriving the solutions of the optimization problems, we give graphical interpretations for the solutions.

• 한국컴퓨터정보학회논문지
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• 제15권10호
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• pp.1-9
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• 2010

본 논문에서는 이종가산기구조에 근거한 이진가산기의 전력-지연시간곱의 최적화 방법론을 제안한다. 정수선형 계획법(Integer Linear Programming)에 의해 이종가산기의 전력-지연시간곱을 공식화하였다. 정수선형계획법의 사용을 위하여 최초의 전력-지연시간곱의 비선형수식을 선형수식으로 변환하는 기법을 채택하였다. 또한, 제안된 방법이 전력지연시간곱(Power-Delay Product)의 척도에서 기존가산기와 비교해 우월함을 실험결과를 통해 확인하였다.

• 한국경영과학회지
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• 제10권1호
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• pp.14-30
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• 1985

Recently, multiple criteria decision making has been well established as a practical approach to seek a satisfactory solution to a decision making problem. Goal programming is one of the most powerful MCDM tools with satisfying operational assumptions that reflect the actual decision making process in real-world situations. In this paper we propose an efficient method implemented on a microcomputer for solving linear goal programming problems. It is an iterative revised goal simplex method using the sparsity technique. We design as interactive software package for microcomputers based on this method. From some computational experiences, we can state that the revised iterative goal simplex method using the sparsity technique is the most efficient one for microcomputer for solving goal programming problems.