• 센서학회지
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• 제26권4호
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• pp.274-279
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• 2017

LCD(Liquid Crystal Display) panel cutting problem is a sort of two dimensional cutting stock problem. A cutting stock problem is problem that it minimizes the loss of the stock when a stock is cut into various parts. In the most research of the two dimensional cutting stock problem, it is supposed that the relative angle of a stock and parts is not important. Usually the angle is regarded as horizontal or perpendicular. In the manufacturing of polarizing film of LCD, the relative angle should be maintained at some specific angle because of the physical and/or chemical characteristics of raw material. We propose a mathematical model for solving this problem, a two-dimensional non-Guillotine cutting stock problem that is restricted by an arranged angle. Some example problems are solved by the C++ program using ILOG CPLEX classes. We could get the verification and validation of the suggested model based on the solutions.

• 한국경영과학회:학술대회논문집
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• 대한산업공학회/한국경영과학회 1996년도 춘계공동학술대회논문집; 공군사관학교, 청주; 26-27 Apr. 1996
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• pp.276-279
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• 1996

This paper deals with the method providing an exact solution to the 3-dimensional guillotine cutting stock problem. We suggest a 3-stage sutting method using the property that cubic material has to be cut into 2-dimensional planes firstly. This method requires more stocks that the general guillotine cutting methods but can save work force. By using the 1-dimensional dynamic programming, we reduce the computational time and the memory requirement in the 3-stage guillotine cutting method.

• 산업경영시스템학회지
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• 제18권35호
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• pp.47-52
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• 1995

The aim of this paper is to suggest the cutting stock problems which are two-dimensional in form, but can be treated as the optimization methods for one-dimensional cutting stock problem by exploiting the length requirement of the products. The solution method consists of two stages. The first calculates the number of roll pieces of each size. Next, 1-dimensional cutting stock model is set up. One heuristic method to calculate the number of each roll is suggested. The trim loss minization criteria are used to design the objective function. This model can be solved by the conventional cutting stock procedures based on enumerating the possible cutting patterns.

• 대한산업공학회지
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• 제22권4호
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• pp.741-751
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• 1996

The three dimensional cutting-stock problem is to maximize the total value of pieces which are smaller cubics-cut from a original cubic stock. This paper suggests a method to maximize the total value of different size cut pieces using the orthogonal non-guillotine cut technique. We first formulated a zero-one integer programming, then developed a Lagrangeon relaxation method far the problem. The solutions were given by using a brunch-end-bound technique associates with Lagrangean relaxation, which guarantees an optimal solution.

• 대한산업공학회지
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• 제27권4호
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• pp.424-431
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• 2001

This paper is concerned with the unconstrained two-dimensional cutting problem of cutting small rectangles (products), each of which has its own profit and size, from a large rectangle (material) to maximize the profit-sum of products. Since this problem is used as a sub-problem to generate a cutting pattern in the algorithms for the two-dimensional cutting stock problem, most of researches for the two-dimensional cutting stock problem have been concentrated on solving this sub-problem more efficiently. This paper improves Hifi and Zissimopoulos's recursive algorithm, which is known as the most efficient exact algorithm, by applying newly proposed upper bound and searching strategy. The experimental results show that the proposed algorithm has been improved significantly in the computational amount of time as compared with the Hifi and Zissimopulos's algorithm.

• 산업공학
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• 제8권2호
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• pp.151-159
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• 1995

Two-dimensional cutting stock problem is to find a waste-minimizing method of cutting a single rectangular plane into a number of smaller pieces of known dimensions. In practice, besides wastes, setup cost taken during adjusting is of an important concern. We suggest 2-phased guillotine cutting method as a solution to the problem which minimize wastes and setup costs. Also, in order to reduce the computing time we apply techniques of discretization, cutoff, median. Experimental results show good performance of our algorithm.

• Journal of information and communication convergence engineering
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• 제8권1호
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• pp.13-18
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• 2010

The composite stock cutting problem is defined as allocating rectangular and irregular patterns onto a large composite stock sheet of finite dimensions in such a way that the resulting scrap will be minimized. In this paper, we introduce a novel approach to hybrid optimization algorithm called MGA in MPI (Message Passing Interface) environments. The proposed MGA combines the benefit of rapid convergence property of Mean Field Annealing and the effective genetic operations. This paper also proposes the efficient data structures for pattern related information.

• 한국컴퓨터정보학회논문지
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• 제14권4호
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• pp.1-8
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• 2009

이 논문에서는 철근 절단 작업의 계획 문제를 동적 계획법으로 해결하여 근사 최적의 절단 계획을 생성하도록 하는 소프트웨어의 구현을 다룬다. 일반적으로 실제 절단 작업에 요구되는 제약사항을 반영하여 최적의 자재 절단문제의 해를 얻는 알고리듬의 설계가 필요하다. 하지만, 이것은 다중 규격의 1차원 자재 절단 문제를 풀어야 하는 것으로, 최적의 해를 얻는 선형계획법은 폭발적인 계산량과 기억용량의 한계로 적용하기 어렵다. 이러한 한계를 해결하기 위하여, 동적계획법에 근거하며 자재 절단 문제를 재구성하고, 휴리스틱을 적용하여 유한 범위의 조합 열에서도 근사 최적의 해를 찾을 수 있는 탐색 기법을 사용한 자재 절단 계획 알고리듬을 제시하였다. 그리고, 자동화된 철근 가공 산업용 소프트웨어는 작업 환경에 맞게 사용이 편리한 그래픽 화면과 사용자 인터페이스가 요구되는데, 공개 소프트웨어를 활용한 GUI 라이브러리 툴킷인 GTK+를 활용하여 이를 구현하였다. 개발된 소프트웨어는 철근 가공의 현장 지식을 바탕으로 휴리스틱 지식을 획득하여 동적계획법에 적용시킨 것으로, 지역 전통 산업과 첨단 IT 산업이 접목된 융합 IT를 시도한 사례 연구이다.

• 한국정보과학회논문지:소프트웨어및응용
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• 제29권1_2호
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• pp.20-29
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• 2002

복합 재료로 구성된 원판으로부터 여러 가지 패턴을 버려지는 부분이 최소화되게 배치시킨 후 절단하는 문제를 복합 재료 재단 문제라 부른다. 본 논문은 목적 함수의 비용 오류를 감내하는 영역 분할 분산 시뮬레이티드 어닐링 알고리즘을 MPI 환경하에서 복합 재료 재단 문제에 적용한다. 비용 오류 감내기법은 최적해 접근 특성을 유지하기 위하여 스트림 길이를 동적으로 변화하며 상태변환을 비동기적으로 수행한다. 또한 복합 재료 재단 도구 개발을 위한 여러 가지 모양을 가진 패턴의 정보 및 친화도 생성, 목적함수, 상태변환 방법, 어닐링 스케줄 및 이를 위한 효율적인 자료 구조에 대하여 정의한다. 배치될 패턴은 정형이나 convex 다각형으로 제한되어 있지 않고 어떠한 모양도 가능하며 원판은 복합 재료의 성격상 2 또는 4 방향으로 고정되어 있다.

• 산업경영시스템학회지
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• 제33권3호
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• pp.30-39
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• 2010

This paper considers a problem of optimizing torch paths to cut stock plates nested with open contours. For each contour, one of the two ending points is to be selected as a starting point of cutting with the other being the exit point. A torch path is composed of a single depot and a series of starting and ending points of contours to be cut. The torch path optimization problem is shown to be formulated as an extended version of the standard travelling salesman problem. To solve the problem, a hybrid genetic algorithm with the local search of torch paths is proposed. The genetic algorithm is tested for hypothetical problems whose optimal solutions are known in advance due to the special structure of them. The computational results show that the algorithm generates very near optimal solutions for most cases of the test problems, which verifies the validity of the algorithms.