• The Transactions of the Korean Institute of Electrical Engineers A
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• v.52 no.7
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• pp.355-362
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• 2003

The fault analysis problem of a distribution network has many difficulties comes from the unbalance of loads or networks and the lacks of load information. The unbalance of loads or networks make the fault location difficult when it use the classical sequence transformation. Moreover the amount of load in the distribution networks fluctuates with time. This paper introduces a recent fault location algorithm using iterative method which handle the unbalance of the problem. But, the fault location errors comes from the load fluctuations still left. For the real application of the new fault location algorithm in distribution networks, this paper studied the effect of the load fluctuations in the algorithm.

• Industrial Engineering and Management Systems
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• v.14 no.1
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• pp.11-21
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• 2015

The purpose of this research is to develop algorithms using the Differential Evolution Algorithm (DE) to solve a multi-objective, sources and stages location-allocation problem. The development process starts from the design of a standard DE, then modifies the recombination process of the DE in order improve the efficiency of the standard DE. The modified algorithm is called modified DE. The proposed algorithms have been tested with one real case study (large size problem) and 2 randomly selected data sets (small and medium size problems). The computational results show that the modified DE gives better solutions and uses less computational time than the standard DE. The proposed heuristics can find solutions 0 to 3.56% different from the optimal solution in small test instances, while differences are 1.4-3.5% higher than that of the lower bound generated by optimization software in medium and large test instances, while using more than 99% less computational time than the optimization software.

• Journal of the Korea Safety Management & Science
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• v.12 no.1
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• pp.97-104
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• 2010

Expanded muti-source Weber problem (EWP), which introduced in this paper, is a reverse logistics network design problem to minimize the total transportation cost from customers thorough regional center to central center. Decision factor of EWP are the locations of regional centers and a central center. We introduce a GRASP heuristics for the EWP. In the suggested GRASP, an expanded iterative location allocation method (EILA) is introduced based on the Cooper's iterative location allocation method[3]. For the initial solution of GRASP, allocation first seed (AFSeed) and location first seed (LFSeed) are developed. The computational experiment for the objective value shows that the LFSeed is better than the AFSeed. Also the calculating time of the LFSeed is better than that of the AFSeed.

• Journal of the Korea Society of Computer and Information
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• v.21 no.3
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• pp.57-64
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• 2016

This paper deals with the PCB assembly time minimization problem that the PAP (pick-and-placement) machine pickup the K-weighted group of N-components, loading, and place into the PCB placement location. This problem considers the rotational turret velocity according to component weight group and moving velocity of distance in two component placement locations in PCB. This paper suggest heavy-weight component group first pick-and-place strategy that the feeder sequence fit to the placement location Hamiltonean cycle sequence. This algorithm applies the quadratic assignment problem (QAP) that considers feeder sequence and location sequence, and the linear assignment problem (LAP) that considers only feeder sequence. The proposed algorithm shorten the assembly time than iATMA for QAP, and same result as iATMA that shorten the assembly time than ATMA.

• IE interfaces
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• v.21 no.3
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• pp.262-273
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• 2008

In Korean peninsular, Air Defense with SAM(Surface-to-Air Missile) is very important, because of threatening by North Korea's theater ballistic missiles installed with nuclear or biochemistry. Effective and successful defense operation largely depends on two factors, SAM's location and the number of SAM for each target based on missile's availability in each SAM's location. However, most previous papers have handled only the former. In this paper, we developed Multi-heuristic algorithm which can handle both factors simultaneously for solving allocation problem of the batteries and missile assignment problem in each battery. To solve allocation problem, genetic algorithm is used to decide location of the batteries. To solve missile assignment problem, a heuristic algorithm is applied to determine the number of SAM for each target. If the proposed model is applied to allocation of SAM, it will improve the effectiveness of missile defense operations.

• Industrial Engineering and Management Systems
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• v.8 no.1
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• pp.29-36
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• 2009

We present two local-search based metaheuristics for the multi-source capacitated facility location problem. In such a problem, each customer's demand can be supplied by one or more facilities. The problem is NP-hard and the number of locations in the optimal solution is unknown. To keep the search process effective, the proposed methods adopt the following features: (1) a multi-exchange neighborhood structure, (2) a tabu list that keeps track of recently visited solutions, and (3) a multi-start to enhance the diversified search paths. The transportation simplex method is applied in an efficient manner to obtain the optimal solutions to neighbors of the current solution under the algorithm framework. Two in-and-out selection rules are also proposed in the algorithms with the purpose of finding promising solutions in a short computational time. Our computational results for some of the benchmark instances, as well as some instances generated using a method in the literature, have demonstrated the effectiveness of this approach.

• Journal of Korean Society of Industrial and Systems Engineering
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• v.7 no.10
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• pp.1-16
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• 1984

The purpose of this paper is to develop rational layout model for small and medium scale industry in Korea. The methodology of this paper is to light the importance of small and medium scale company. Moreover, to overcome the problem of layout in non-massing jobbing production shop this paper is proposed four techniques. So proposed layout model is obtained analytically in single, multiple facility location problem The result of this paper is as follows : First, alternatives to overcome abnormal layout in small and medium company are 1) GT (Group Technology) 2) SLP (Systematic Layout Planning) 3) OR (Operations Research) 4) Computer Second, in single facility location problem, Gradient method and square weighted average method are studied. Lastly in multiple facility location problem, heuristic method is obtained.

• Journal of Korean Society of Industrial and Systems Engineering
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• v.19 no.37
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• pp.263-269
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• 1996

The cost and customer service level of a logistics system depend primarily on the system design of the physical supply system and physical distribution system. The study presents the mathematical model and a huristic solution method of a combined location - vehicle routing problem(LVRP). In LVRP the objective is to determine the number and location of the distribution centers, the allocation of customers to distribution centers, and the vehicle delivery routes, so as to minimize the logistics total cost and satisfy the customer.

• Journal of Korean Society of Industrial and Systems Engineering
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• v.14 no.23
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• pp.1-6
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• 1991

The physical distribution service(PDS) is essential to evaluate the business logistics system. The PDS combines the inventory service with the lead time to deliver. This paper is presented to model Mixed Zero-One integer programming which is to determine distribution center location and to allocation products, considering delivery lead time, from given candidate locations to given customer markets. A numerical example is given to demonstrate the applicability of Mixed Zero-One integer programming for Distribution-Location problem.

• Industrial Engineering and Management Systems
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• v.8 no.4
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• pp.228-238
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• 2009

This paper first presents two supply chain design problems: 1) a factory location setting and factory selection problem, and 2) a factory location setting and factory/supplier selection problem. The first involves a number of location known retailers choosing one factory to supply their demands from a number of factories whose locations are to be determined. The goal is to minimize the transportation and manufacturing cost to satisfy the demands. The problem is then augmented into the second problem, where the procurement cost of the raw materials from a chosen material supplier (from a number of suppliers) is considered for each factory. Economic beneficial is taken into account in the cost evaluation. Therefore, the partner selections will influence the cost of the supply chain significantly. To solve these problems, an agent gaming and genetic algorithm hybrid method (AGGAHM) is proposed. The AGGAHM consecutively and alternatively enable and disable the advancement of agent gaming and the evolution of genetic computation. Computation results on solving a number of examples by the AGGAHM were compared with those from methods of a general genetic algorithm and a mutual frozen genetic algorithm. Results showed that the AGGAHM outperforms the methods solely using genetic algorithms. In addition, various parameter settings are tested and discussed to facilitate the supply chain designs.