• Title/Summary/Keyword: Heuristic approach

검색결과 533건 처리시간 0.029초

a hybrid approach for jobshop scheduling with lot-streaming

  • 김인수;서윤호
    • 한국품질경영학회:학술대회논문집
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    • 한국품질경영학회 2007년도 춘계학술대회
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    • pp.491-497
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    • 2007
  • The planning and scheduling is considered as an important function because it influence to the overall performance of production in manufacturing system for supporting global objectives. In this paper, propose the hybrid approach to solve the problem which considered alternative resources and sequences, a sequence-dependent setups and transportation times. The objective of this problem is minimize the makespan with AGV traveling time. A iterative two heuristic algorithm(PSO, SA) is proposed to obtain the sequence of operations and CPLEX package is used to obtain the optimal sub-lot sizes(OLS) when the sequence of operations and greedy-based AGV dispatching rules are fixed or given. we show that performance of iterative two heuristic algorithms and simple numerical experiment.

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Unsupervised Segmentation of Images Based on Shuffled Frog-Leaping Algorithm

  • Tehami, Amel;Fizazi, Hadria
    • Journal of Information Processing Systems
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    • 제13권2호
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    • pp.370-384
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    • 2017
  • The image segmentation is the most important operation in an image processing system. It is located at the joint between the processing and analysis of the images. Unsupervised segmentation aims to automatically separate the image into natural clusters. However, because of its complexity several methods have been proposed, specifically methods of optimization. In our work we are interested to the technique SFLA (Shuffled Frog-Leaping Algorithm). It's a memetic meta-heuristic algorithm that is based on frog populations in nature searching for food. This paper proposes a new approach of unsupervised image segmentation based on SFLA method. It is implemented and applied to different types of images. To validate the performances of our approach, we performed experiments which were compared to the method of K-means.

공 컨테이너를 고려한 컨테이너 내륙수송에서의 차량배차문제 (A Truck Dispatching Problem in the Inland Container Transportation with Empty Container)

  • 윤원영;안창근;최용석
    • 한국경영과학회지
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    • 제24권4호
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    • pp.63-80
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    • 1999
  • In the container transportation of inland depots the empty container is an important issue. The truck dispatching problem in this paper is considered under restriction about empty containers. When a full container arrives in a depot by truck, after unloading operation the full container is changed to an empty container. After loading operation an empty container is changed to a full container. We suggest an integrated approach to the problem of simultaneously managing empty truck and container movements. We suggest an integrated approach to the problem of simultaneously managing empty truck and container movements. We would like to find the truck dispatching method minimizing empty truck movements and empty container movements. In this paper, a mixed integer programming model is developed to obtain the optimal truck dispatching in container transportation and heuristic is developed to give a good solution in much shorter time. The numerical examples are studied and the proposed heuristic is also compared with the result of numerical examples.

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경험적 접근법과 동역학적 특성에 기반한 4WD 차량의 제어 전략 개발 (Control Strategy Development of 4WD Vehicles based on Heuristic Approach and Dynamic Characteristic)

  • 함형진;이형철
    • 한국자동차공학회논문집
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    • 제21권6호
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    • pp.209-217
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    • 2013
  • This paper presents a control strategy of 4 wheel drive (4WD) vehicles. Proposed control strategy has simple structure and can easily apply to various vehicles with low cost and time. It is consist of feedforward control for traction ability, fedback control for minimizing the wheel speed difference and yaw control for lateral stability. In addition, to integrate the traction and stability control, a blending function is applied. To evaluate the feasibility of the proposed control strategy, actual vehicle experiment is conducted after deciding the tuning parameter through the simulation. The simulation is accomplished by CarSim and Matlab/Simulink and the actual vehicle test is conducted using full size Sports Utility Vehicle (SUV) equipped rear wheel based solenoid type 4WD device.

유전 알고리듬을 이용한 무인운반차시스템의 운반경로 결정 (Determination of Guide Path of AGVs Using Genetic Algorithm)

  • 장석화
    • 산업경영시스템학회지
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    • 제26권4호
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    • pp.23-30
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    • 2003
  • This study develops an efficient heuristic which is based on genetic approach for AGVs flow path layout problem. The suggested solution approach uses a algorithm to replace two 0-1 integer programming models and a branch-and-bound search algorithm. Genetic algorithms are a class of heuristic and optimization techniques that imitate the natural selection and evolutionary process. The solution is to determine the flow direction of line in network AGVs. The encoding of the solutions into binary strings is presented, as well as the genetic operators used by the algorithm. Genetic algorithm procedure is suggested, and a simple illustrative example is shown to explain the procedure.

작업순서를 고려한 효율적인 제조셀 형성방법 (An Efficient Cell Formation Approach for a Cellular Manufacturing System Considering Operation Sequences)

  • 정병희;최동순
    • 산업공학
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    • 제10권3호
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    • pp.189-196
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    • 1997
  • This paper presents a cell formation approach for a cellular manufacturing system to minimize the inter-cell moves considering operation sequences. Two new factors are introduced: (1)flow-similarity(FS) for integrating direct/indirect inter-machine flow and similarity (2)machine cell-part moves (CPM) for exactly computing inter-cell moves. FS is used for combining machines and CPM is used for assigning the parts to the preliminary machine cells. In addition, we develop an aggregated heuristic algorithm to form manufacturing machine cells and assign the parts to those cells based on these concepts. We use performance criterion called total inter-cell moves(TICM), which is the total material flow between internal cells and external cells. Results of computational tests on a number of randomly generated test problems show that the suggested heuristic is superior to existing methods.

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Multi-objective Capacitor Allocations in Distribution Networks using Artificial Bee Colony Algorithm

  • El-Fergany, Attia;Abdelaziz, A.Y.
    • Journal of Electrical Engineering and Technology
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    • 제9권2호
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    • pp.441-451
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    • 2014
  • This article addresses an efficient heuristic-based approach to assign static shunt capacitors along radial distribution networks using the artificial bee colony algorithm. The objective function is adapted to enhance the overall system static voltage stability index and to achieve maximum net yearly savings. Load variations have been considered to optimally scope the fixed and switched capacitors required. The numerical results are compared with those obtained using recent heuristic methods and show that the proposed approach is capable of generating high-grade solutions and validated viability.

Building a Model(s) to Examine the Interdependency of Content Knowledge and Reasoning as Resources for Learning

  • Cikmaz, Ali;Hwang, Jihyun;Hand, Brian
    • 한국수학교육학회지시리즈D:수학교육연구
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    • 제25권2호
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    • pp.135-158
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    • 2022
  • This study aimed to building models to understand the relationships between reasoning resources and content knowledge. We applied Support Vector Machine and linear models to the data including fifth graders' scores in the Cornel Critical Thinking Test and the Iowa Assessments, demographic information, and learning science approach (a student-centered approach to learning called the Science Writing Heuristic [SWH] or traditional). The SWH model showing the relationships between critical thinking domains and academic achievement at grade 5 was developed, and its validity was tested across different learning environments. We also evaluated the stability of the model by applying the SWH models to the data of the grade levels. The findings can help mathematics educators understand how critical thinking and achievement relate to each other. Furthermore, the findings suggested that reasoning in mathematics classrooms can promote performance on standardized tests.

가격할인이 있는 단일품목 동적 재고모델의 발주정책을 위한 발견적 기법 (A Heuristic Method for Ordering in the Dynamic Inventory System with Quantity Discounts)

  • 이영조;강맹규
    • 대한산업공학회지
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    • 제12권2호
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    • pp.77-87
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    • 1986
  • This paper presents a heuristic method for solving the discrete-time ordering problem with quantity discounts and deterministic, time-varying demand. This algorithm utilizes a variation of the incremental cost approach(ICA) to determine a near optimal solution. The ICA is the method which reduces the total cost with reduction of the number of orders by one. In order to reduce the number of orders, if the incremental cost for one of the periods is negative, the demand of the period should be purchased in its immediate preceding period. In order to test the performance of this algorithm, an experiment is conducted that involves a large number of test problems covering a wide variety of situations. The result of the experiment shows that the proposed algorithm has 80.5% better solutions than the adjusted part period algorithm(APPA), which is known to be the best heuristic method.

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개미 군집 최적화 기법을 활용한 최대 독립 마디 문제에 관한 해법 (An Ant Colony Optimization Approach for the Maximum Independent Set Problem)

  • 최화용;안남수;박성수
    • 대한산업공학회지
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    • 제33권4호
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    • pp.447-456
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    • 2007
  • The ant colony optimization (ACO) is a probabilistic Meta-heuristic algorithm which has been developed in recent years. Originally ACO was used for solving the well-known Traveling Salesperson Problem. More recently, ACO has been used to solve many difficult problems. In this paper, we develop an ant colony optimization method to solve the maximum independent set problem, which is known to be NP-hard. In this paper, we suggest a new method for local information of ACO. Parameters of the ACO algorithm are tuned by evolutionary operations which have been used in forecasting and time series analysis. To show the performance of the ACO algorithm, the set of instances from discrete mathematics and computer science (DIMACS)benchmark graphs are tested, and computational results are compared with a previously developed ACO algorithm and other heuristic algorithms.