• Water for future
• /
• v.27 no.4
• /
• pp.59-67
• /
• 1994

The objective of this study is to develop a method which can design an optimal pipe network system using nonlinear programming(NLP) technique. The method finds the minimum-cost pipe network while satisfying all the design constraints including hydraulic constraints. The method developed in this study was applied to the Goyang distribution area in Goyang, Kyoungi-do. It has been found in the application and the comparison between the original design and the optimal design of this study that the optimal design method developed in this study does not require the trial-and-error procedure while satisfying the discharge and pressure requirements at the demanding nodes. Therefore, the optimal design method using NLP could be effectively utilized in the practical design considering economic aspect of the pipe network system at the same time.

• Proceedings of the KIEE Conference
• /
• 2006.07a
• /
• pp.311-312
• /
• 2006

본 논문에서는 선로 전력조류제약을 고려한 경제급전(SCED : Security-Constrained economic dispatch)에 내점 선형계획법을 이용하여 최적해를 구하는 문제를 다룬다. 최적전력조류(Optimal Power Flow)식으로부터 선로의 유효전력만을 근사화하여 선로 전력조류 제약을 고려할 경제급전(SCED)의 식을 정식화한다. 선형계획법을 적용하여 최적해를 구하기 위해서 발전기출력과 유효전력, 부하, 손실과의 관계를 이용하여 경제급전의 식을 선형화 하는 알고리즘을 제시한다. 선형화 알고리즘은 목적함수로 계통 발전기의 총 연료비를 취하고 전력수급평형식으로 발전기출력증분에 대한 선로의 증분손실계수를 이용하며, 선로의 제약조건은 일반화발전 분배계수(GGDF : Generalized Generation Distribution Factor)를 이용하여 선형화한다. 최적화 기법으로서 내점법(Interior Point Method)을 적용하고자 하며 사례연구를 통하여 선형계획법 중 가장 많이 사용하는 심플렉스(Simplex)법과의 수렴특성을 비교하여 내점 법의 효용성을 확인하고자 한다.

• Magazine of the Korean Society of Agricultural Engineers
• /
• v.37 no.1
• /
• pp.90-99
• /
• 1995

In this study, the algorithm for the optimum design of cantilever retaining wall was de veloped and solved using Modified Method of Feasible Directions(MMFD), Sequential Linear Programming(SLP) and Sequential Quadratic Programming(SQP). The algorithm was applied to the optimum design of 3-different height cantilever re tairing walls. It was shown that even though the starting points and optimization strategies are dif- ferent, the objective function and optimum design variables converge to within a close range, and consequently the reliability and efficiency of the underlying optimum design algorithm can be verified. It is expected that the optimum design algorithm developed in this study can be utilized efficiently for the optimum design of any scale cantilever retaining wall. Using optimum design method, cantilever retaining wall will be designed more economi- cally and reasonably than using traditional design method.

• Journal of the Korea Society of Computer and Information
• /
• v.15 no.10
• /
• pp.1-9
• /
• 2010

In this paper, we propose a methodology in which a power-delay product of a binary adder is optimized based on the heterogeneous adder architecture. We formulate the power-delay product of the heterogeneous adder by using integer linear programming(ILP). For the use of ILP optimization, we adopt a transformation technique in which the initial non-linear expression for the power-delay product is converted into linear expression. The experimental result shows the superiority of the suggested method compared to the cases in which only conventional adder is used.

• The Korean Journal of Applied Statistics
• /
• v.30 no.6
• /
• pp.931-941
• /
• 2017

Typical Nonparametric methods for randomized block design with replications are two methods proposed by Mack (1981) and Mack and Skillings (1980). This method is likely to cause information loss because it uses the average of repeated observations instead of each repeated observation in the processing of each block. In order to compensate for this, we proposed a test method using linear placement statistics, which is a score function applied to the joint placement method proposed by Chung and Kim (2007). Monte Carlo simulation study is adapted to compare the power with previous methods.

• Proceedings of the Korean Operations and Management Science Society Conference
• /
• 1995.09a
• /
• pp.189-199
• /
• 1995

내부점 방법에서는 개선 방향을 대칭 양정치 행렬로 이루어지는 선형시스템 의 해를 구해야 하고 단체법에서는 단체 승수나 진입열을 계산하는데 기저 행렬로 이루어지는 선형시스템을 풀게된다. 본 연구는 내부점 기법과 단체법 에서 나타나는 선형시스템을 QR분해를 통해 푸는 방법을 구현하고 이에 대 한 결과를 제시하였다. QR분해 방법으로는 Givens가 제시한 방법을 사용했 으며 단체법에서 rank-one 수정 방법을 사용하였다. QR분해를 적용한 단체 법의 경우는 상.하 분해를 단체법에 비해 많이 느리며 내부점 기법에 적용하 면 촐레스키 분해보다 2-8배 정도 수행시간이 더 소요되었다. 그러나 내부점 기법에서 QR분해 방법이 촐레스키 분해 방법에 비해 보다 수치적으로 보다 정확하였다.

• KIEAE Journal
• /
• v.3 no.2
• /
• pp.17-24
• /
• 2003

The purpose of this study is to present rational methods of multi-criteria optimization of the envelope of buildings. The object is to determine the optimum R-value of the envelope of a building, based on the following criteria: minimum building costs (including the cost of materials and construction) and yearly heating costs. Mathematical model described heat losses and gains in a building during the heating season. It takes into consideration heat losses through wall, roof, floor and windows. Particular attention was paid to have a more detailed description of heat gains due to solar radiation. On the assumption that shape of building is rectangle in order to solve the problem, optimum R-value of the envelope of a building is determined by using non-linear programing methods(Kuhn-Tucker Conditions). The results constitute information for designers on the optimum R-value of a building envelope for energy saving buildings.

• The Korean Journal of Applied Statistics
• /
• v.29 no.7
• /
• pp.1411-1419
• /
• 2016

Nonparametric procedures in randomized block design was proposed by Friedman (1937) as a general alternative. This method is used to find out the difference in treatment effect. It can cause a loss of inter block information using the ranking in each block. This paper proposed nonparametric procedures using an aligned method proposed by Hodges and Lehmann (1962) to reduce block information based on joint placement suggest by Jo and Kim (2013) in a randomized block design. We also compared the power of the test of the proposed procedures and established method through a Monte Carlo simulation.

• Magazine of the Korean Society of Agricultural Engineers
• /
• v.36 no.2
• /
• pp.111-122
• /
• 1994

In this study, an algorithm which can be applied to the optimum design of simple steel plate girders was developed, and efficient optimization strategies for the solution of algorithm were found out. The optimum design algorithm consists of 3-levels of optimization. In the first and second levels of optimization, the absolute maximum bending moment and shearing force are extracted and in the third level of optimization, the optimum cross section of steel plate girder is determined. For the optimum design of cross section, the objective function is formulated as the total area of cross section and constraints are derived in consideration of the various stresses and the minimum dimension of flange and web based on the part of steel bridge in the Korea standard code of road bridge. Sequential unconstrained minimization technique using the exterior penalty function method(SUMT-EP), sequential linear programming(SLP) and sequential quadratic programming (SQP) are proved to be efficient and robust strategies for the optimum design of simple plate girder cross section. From the reliable point of view, SLP is the most efficient and robust strategy and SQP is the most efficient one from the viewpoint of converguency and computing time.

• Proceedings of the Korean Operations and Management Science Society Conference
• /
• 1995.09a
• /
• pp.211-219
• /
• 1995

블록-삼각(Block-angular)구조를 갖는 선형 제약식과 분리되지 않는 콘벡스 목적함수의 대규모 비분리 콘벡스 최적화 문제의 해법으로 번들-분해법 (Bundle Based Decomposition)을 이용한 알고리즘 SQA(Separable Quadratic Approximation)은 비분리 콘벡스 프로그램을 분리가능한 2차계획 법(Separable Quadratic Programming) 문제로 근사화시켜 번들-분해법을 축 차적으로 적용한다. 본 연구는 수렴성(local convergence & global convergence) 및 알고리즘 구현 [1]에 이어 이에 대한 수치적용 결과를 중심 으로 소개한다. 수치 적용은 ANSI C로 작성된 SQA 프로그램을 SUN SPARC II에서 실행하였으며 이때 대규모 비분리 최적화 문제의 비분리 목 적함수와 블록-삼각 구조의 선형 제약식들이 계수들은 ANSI C의 랜덤함수 로부터 임의의 값들을 이용하였다. 이와같은 다양한 비분리 콘벡스 최적화 문제에 대한 수렴성, 반복회수 및 처리시간등의 결과와 함께 GAMS/MINOS 의 최적해를 소개한다.