• 제목/요약/키워드: Cutting Problem

검색결과 426건 처리시간 0.023초

A* 알고리즘을 적용한 금속 그레이팅 생산 공정에서의 절단문제 해결 (Application of A* Algorithm to solve a Cutting Problem in Metal Manufacturing Process)

  • 김진명;조대호
    • 한국시뮬레이션학회논문지
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    • 제14권4호
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    • pp.1-8
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    • 2005
  • In a metal grating manufacturing process, the cutting operation allocates the gratings and cut them out from given panels or a plate sheets. Before the cutting operation an operator generates a cutting plan. The cutting plan should decide how pieces of metal rectangles i.e., gratings, are allocated and cut from the panel. This plan generation is a deal of weight on the production cost. the generation of cutting plan is similar to the general two-dimensional cutting problem. In this paper, we first define cutting problem and Af algorithm of Artificial Intelligence to solve the problem. Also, through a simulation, we compare the proposed cutting algorithm to an existing method in terms of material loss

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개수 제한이 없는 2차원 절단문제를 위한 향상된 최적해법 (An Improved Exact Algorithm for the Unconstrained Two-Dimensional Cutting Problem)

  • 지영근;강맹규
    • 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.

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0-1 혼합정수계획법을 이용한 LCD 패널 절단 문제 최적화 (Optimization of LCD Panel Cutting Problem Using 0-1 Mixed Integer Programming)

  • 김기동;박현지;심윤섭;전태보
    • 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.

3차원 기로틴 3단계 자재절단 방법에 관한 연구 (A study on the 3-stage 3-dimensional guillotine cutting-stock problem)

  • 김상열;박순달
    • 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.

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An experimental study on the development and verification of NCC(new concrete cutting) system

  • Park, Jong-Hyup;Han, Jong-Wook
    • Structural Engineering and Mechanics
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    • 제65권2호
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    • pp.203-211
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    • 2018
  • This paper introduces the development process of NCC(New Concrete Cutting) system and analyzes first verification test. Based on the first verification test results, some problems of NCC system have been newly modified. We carry out the second verification test. We tried to verify cutting performance and dust control efficiency of NCC system through the cutting test of concrete bridge piers. In particular, this verification test strives to solve the problem of concrete dust, which is the biggest problem of dry cutting method. The remaining dust problems in cutting section tried to solve through this verification test. This verification test of the NCC system shows that the dust problem of dry cutting method is closely controlled and solved. In conclusion, the proposed NCC method is superior to the dry cutting method in all aspects, including cutting performance, dust vacuum efficiency and cooling effect. The proposed NCC system is believed to be able to provide eco-friendly cutting technology to various industries, such as the removal of the SOC structures and the dismantling of nuclear plants, which have recently become a hot issue in the field of concrete cutting.

무제한 3차원 절단문제를 위한 새로운 분지 한계법 (A New branch and bound algorithm for unconstrained three-dimensional cutting problems)

  • Young-Jo Seong;Maing-Kyu Kang
    • 한국컴퓨터산업학회논문지
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    • 제5권3호
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    • pp.377-382
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    • 2004
  • 무제한 3차원 절단문제는 커다란 직육면체 자재에서 작은 직육면체 제품을 잘라낼 때, 잘라낸 제품의 가치가 최대가 되도록 하는 절단패턴을 찾는 문제이다. 이 때, 잘려지는 각각의 제품은 고유의 크기와 가치를 갖는다. 두 개의 절단패턴을 결합해서 새로운 절단패턴을 만들어 내는 상향식 접근법은 무제한 3차원 절단문제를 푸는 해법으로 사용할 수 있다. 본 논문에서는, Wang이 제안한, 2차원 문제에서 사용되는 두 가지 결합 외에 새로운 결합을 정의하고, 지 등이 무제한 2차원 절단 문제를 풀기 위해 제안한 분지전략을 3차원 문제에서 사용할 수 있도록 새롭게 재구성한다.

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동적계획법을 이용한 철근가공용 소프트웨어의 구현 (An Implementation of Cutting-Ironbar Manufacturing Software using Dynamic Programming)

  • 김성훈
    • 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.

Branch-and-Cut 알고리즘에서 Lot-Sizing 문제에 대한 Cutting Planes의 전산 성능 연구 (Computational Study of Cutting Planes for a Lot-Sizing Problem in Branch-and-Cut Algorithm)

  • 정광헌
    • 한국경영과학회지
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    • 제40권3호
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    • pp.23-38
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    • 2015
  • In this paper, we evaluate the strength of three families of cutting planes for a lot-sizing problem. Lot-sizing problem is very basic MIP model for production planning and many strong valid inequalities have been developed for a variety of relaxations in the literature. To use three families of cutting planes in Branch-and-Cut framework, we develop separation algorithms for each cut and implement them in CPLEX. Then, we perform computational study to compare the effectiveness of three cuts for randomly generated instances of the lot-sizing problem.

레이저 절단공정에서의 토지경로 생성에 관한 연구 (A Study on Torch Path Generation for Laser Cutting Process)

  • 한국찬;나석주
    • 대한기계학회논문집A
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    • 제20권6호
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    • pp.1827-1835
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    • 1996
  • This paper addresses the problem of a torch path generation for the 2D laser cutting of a stock plate nested with resular or irregular parts. Under the constaint of the relative positions of parts enforced by nesting, the developed torch path algorithm generate feasible cutting path. In this paper, the basic object is a polygon( a many-slide figure) with holes. A part may be represented as a number of line segments connected end-to-end in counterclockwise order, and formed a closed contour as requied for cutting paths. The objective is to tranverse this cutting contours with a minimum path length. This paper proposes a simulated annealing based dtorch path algorithm, that is an improved version of previously suggested TSP models. Since everypiercing point of parts is not fixed in advance, the algorithm solves as relazed optimization problem for the constraint, thich is one of the main features of the proposed algorithm. For aolving the torch path optimization problem, an efficient generation mechanism of neighborhood structure and as annealing shedule were introduced. In this way, a global solution can be obtained in a reasonable time. Seveeral examples are represented to ilustrate the method.

습식워터젯을 채용한 초정밀 절삭 가공시스템의 특허동향조사에 관한 연구 (Research for Patent Application Tendency in the Super Fine Machining System Using the Wet Waterjet)

  • 김성민;고준빈;박희상
    • 한국공작기계학회논문집
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    • 제18권1호
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    • pp.1-12
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    • 2009
  • Presently, the semiconductor industry has the chronic problem. In the semiconductor industry, it has the semiconductor wafer, a package, the optical filter cut by using the saw blade, the mold, a laser etc. The cutting technique has the difficulty due to the rising of the production cost by the wearing of mold, the poor quality problem due to generated heat at the moment of cutting procedure and curve cutting etc. The goal of this time of national research and development project is develop the apparatus for solving the problem that the existing cutting technique has. The technology is so called waterjet abrasive method. This technology will be mainly applied to cut a semiconductor package and a wafer. Two important things to be considered are ripple effect(in other words, the scale of a market) and simplicity of an application.