• 한국CDE학회논문집
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• 제6권3호
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• pp.174-183
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• 2001

This study proposes an improved genetic algorithm (GA) to derive solutions for facility layout problems having inner walls and passages. The proposed algorithm models the layout of facilities on a flour-segmented chromosome. Improved solutions are produced by employing genetic operations known as selection, crossover, inversion, mutation, and refinement of these genes for successive generations. All relationships between the facilities and passages are represented as an adjacency graph. The shortest path and distance between two facilities are calculated using Dijkstra's algorithm of graph theory. Comparative testing shows that the proposed algorithm performs better than other existing algorithm for the optimal facility layout design. Finally, the proposed algorithm is applied to ship compartment layout problems with the computational results compared to an actual ship compartment layout.

• 품질경영학회지
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• 제19권1호
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• pp.151-162
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• 1991

The purpose of this study is to propose a facility layout design algorithm based on artificial intelligence concept, and then to develop a computer program which is more practical than any other conventional facility layout design systems. The algorithm is composed of five step layout procedures; knowledge and data input, knowledge interpretation, priority determination, inference of layout design, and evaluation, In the step of priority determination, the algorithm is divided into single row and multi row layout problem. In the step of inference of layout design, alternatives are generated by constraints-directed reasoning and depth first search method based on artificial intelligence concept. Alternatives are evaluated by the moving cost and relationship value by interactive man-machine interface in the step of evaluation. As a case study, analytical considerations over conventional programs such as CRAFT and CORELAP was investigated and compared with algorithm propsed in this study. The proposed algorithm in this study will give useful practical tool for layout planner. The computer progran was written in C language for IBM PC-AT.

• 한국정밀공학회지
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• 제29권4호
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• pp.469-478
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• 2012

This study aims to discover the optimal pipe layout for a ship, which generally needs a lot of time, efforts and experiences. Genetic algorithm was utilized to search for the optimum. Here the optimum stands for the minimum pipe length between two given points. Genetic algorithm is applied to planar pipe layout problems to confirm plausible and efficiency. Sub-programs are written to find optimal layout for the problems. Obstacles are laid in between the starting point and the terminal point. Pipe is supposed to bypass those obstacles. Optimal layout between the specified two points can be found using the genetic algorithm. Each route was searched for three case models in two-dimensional plane. In consequence of this, it discovered the optimum route with the minimized distance in three case models. Through this study, it is possible to apply optimization of ship pipe route to an actual ship using genetic algorithm.

• 한국항해항만학회:학술대회논문집
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• 한국항해항만학회 2000년도 추계학술대회논문집
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• pp.131-142
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• 2000

Facility layout is the early stage of system design that requires a mid-term or long-term plan. Since improper facility layout might incur substantial logistics cost including material handling and re-installment costs, due consideration must be given to decisions on facility layout. Facility layout is concerned with low to arrange equipment necessary for production in a given space. Its objective is to minimize the sum of all the products of each equipment's amount of flow multiplied by distance. Facility layout also is related to the issue of NP-complete, i.e., calculated amounts exponentially increase with the increase of the number of equipment. This study discusses Hybrid GA developed, as an algorithm for facility layout, to solve the above-mentioned problems. The algorithm, which is designed to efficiently place equipment, automatically produces a horizontal passageway by the block, if a designer provides the width and length of the space to be handled. In addition, this study demonstrates the validity of the Algorithm by comparing with existing algorithms that have been developed. We present a Hybrid GA approach to the facility layout problem that improves on existing work in terms of solution quality and method. Experimental results show that the proposed algorithm is able to produce better solution quality and more practical layouts than the ones obtained by applying existing algorithms.

• Industrial Engineering and Management Systems
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• 제3권2호
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• pp.123-128
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• 2004

A tree structure model has been proposed for representing the unequal-area facility layout. Each facility has a different rectangular shape specified by its area and aspect ratio. In this layout problem, based on the assumption that the shop floor has enough space for laying out the facilities, no constraint is considered for a shop floor. Objectives are minimizing total part movement between facilities and total rectangular layout area where all facilities and dead spaces are enclosed. Using the genetic code corresponding to two kinds of information, facility sequence and branching positions in the tree structure model, a genetic algorithm has been applied for finding non-dominated solutions in the two-objective layout problem. We use three kinds of crossover (PMX, OX, CX) for the former part of the chromosome and one-point crossover for the latter part. Two kinds of layout problems have been tested by the proposed method. The results demonstrate that the presented algorithm is able to find good solutions in enough short time.

• 대한전자공학회:학술대회논문집
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• 대한전자공학회 2002년도 ITC-CSCC -3
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• pp.1654-1657
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• 2002

This paper presents a system for facility layout problem using an expert system and a genetic algorithm. The practical facility layout design can be effected by characteristics of constructing model, slicing tree model, closeness weight metric and expert system. The genetic algorithm searches the result layout. An experimental system is implemented and produced desired layout.

• 대한기계학회논문집
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• 제17권12호
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• pp.3063-3072
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• 1993

The layout is an important and difficult problem in industrial applications like sheet metal manufacturing, garment making, circuit layout, plant layout, and land development. The module layout problem is known to be non-deterministic polynomial time complete(NP-complete). To efficiently find an optimal layout from a large number of candidate layout configuration a heuristic algorithm could be used. In recent years, a number of researchers have investigated the combinatorial optimization problems by using neural network principles such as traveling salesman problem, placement and routing in circuit design. This paper describes the application of Self-organizing Feature Maps(SOM) of the Kohonen network and Simulated Annealing Algorithm(SAA) to the layout problem of the two-dimensional rectangular shapes.

• 해양환경안전학회지
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• 제19권3호
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• pp.277-284
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• 2013

To ensure that the production system of a factory is efficient, the factory layout design should consider the location and material flow plans of facilities, workshops, and storage areas. Highly productive factories need to have an optimized layout planning process, and a customized design methodology of the production system is a necessity for feasible layout planning. This paper presents a method for designing a layout module's size and shape and provides a heuristic location-allocation algorithm for the modules. The method is implemented and validated using a rich internet application-based platform. The layout design method is based on the leisure ship production process; this method can be used for designing the layout of a new factory or remodeling an existing factory and its production system. In contrast to existing layout methods, the inputs required for the proposed method, such as target products, production processes, and human-resource plans, are simple. This layout design method provides a useful solution for the initial stage of factory design.

• 대한기계학회논문집A
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• 제27권9호
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• pp.1546-1554
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• 2003

Efficient layout in a fixed work volume reduces build time when multiple parts are built at once in stereolithography systems. An efficient algorithm is developed for 3D layout planning. And it reduces build time and increases efficiency of SLA system. Genetic algorithm is implemented to locate as many parts as possible in the fixed work volume. A 3D collision detection algorithm, k-DOPs Tree, is implemented for the fast evaluation of a layout plan.

• 산업경영시스템학회지
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• 제34권4호
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• pp.129-137
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• 2011

To date, facility layout problems has been solved and applied for job shop situations. Since flow shop has more restrictions, the solution space is much smaller than job shop. An efficient heuristic algorithm for facility layout problems for flow shop layouts is needed to be developed. In this thesis, a heuristic algorithm for rectangular bay layouts in a flow shop situation is presented. The proposed algorithm is developed by using slicing tree representation and applied to various flow shop layout problems. The effectiveness of the proposed algorithm in terms of exploration rate and objective function value are shown by comparing our results to simulated annealing.