• Title/Summary/Keyword: Genetic theory

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Efficient Genetic Algorithm for Resource Constrained Project Scheduling Problem (자원 제약이 있는 프로젝트 스케줄링을 위한 효율적인 유전알고리즘)

  • Lee, Sang-Wook
    • The Journal of the Korea Contents Association
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    • v.11 no.6
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    • pp.59-66
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    • 2011
  • Resource constrained project scheduling problem with multiple resource constraints as well as precedence constraints is well-known as one of the NP-hard problem. Since these problems can't be solved by the deterministic method during reasonable time, the heuristics are generally used for getting a sub-optimal during reasonable time. In this paper, we introduce an efficient genetic algorithm for resource constrained project scheduling problem using crossover which is applying schema theory and real world tournament selection strategy. Experimental results showed that the proposed algorithm is superior to conventional algorithm.

Optimal Structure of Modular Wavelet Network Using Genetic Algorithm (유전 알고리즘을 이용한 모듈라 웨이블릿 신경망의 최적 구조 설계)

  • Seo, Jae-Yong;Cho, Hyun-Chan;Kim, Yong-Taek;Jeon, Hong-Tae
    • Journal of the Institute of Electronics Engineers of Korea SC
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    • v.38 no.5
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    • pp.7-13
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    • 2001
  • Modular wavelet neural network combining wavelet theory and modular concept based on single layer neural network have been proposed as an alternative to conventional wavelet neural network and kind of modular network. In this paper, an effective method to construct an optimal modular wavelet network is proposed using genetic algorithm. Genetic Algorithm is used to determine dilations and translations of wavelet basis functions of wavelet neural network in each module. We apply the proposed algorithm to approximation problem and evaluate the effectiveness of the proposed system and algorithm.

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A Study on Improvement of Genetic Algorithm Operation Using the Restarting Strategy (재시동 조건을 이용한 유전자 알고리즘의 성능향상에 관한 연구)

  • 최정묵;이진식;임오강
    • Journal of the Computational Structural Engineering Institute of Korea
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    • v.15 no.2
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    • pp.305-313
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    • 2002
  • The genetic algorithm(GA), an optimization technique based on the theory of natural selection, has proven to be relatively robust means to search for global optimum. It is converged near to the global optimum point without auxiliary information such as differentiation of function. When studying some optimization problems with continuous variables, it was found that premature saturation was reached that is no further improvement in the object function could be found over a set of iterations. Also, the general GA oscillates in the region of the new global optimum point so that the speed of convergence is decreased. This paper is to propose the concept of restarting and elitist preserving strategy as a measure to overcome this difficulty. Some benchmark examples are studied involving 3-bar truss and cantilever beam with plane stress elements. The modifications to GA improve the speed of convergence.

Optimum Design of Greenhouse Structures Using Continuous and Discrete Optimum Algorithms (연속 및 이산화 최적알고리즘에 의한 단동온실구조의 최적설계)

  • Park, Choon-Wook;Lee, Jong-Won;Lee, Hyun-Woo;Lee, Suk-Gun
    • Journal of Korean Association for Spatial Structures
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    • v.5 no.4 s.18
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    • pp.61-70
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    • 2005
  • In paper the discrete optimum design program was developed using the continuous and discrete optimum algorithms based on the SUMT and genetic algorithms. In this paper, the objective function is the weight of structures and the constraints are limits state design limits method. The design variables are diameter and thick of steel pipe. Design examples are given to show the applicability of the optimum design using the continuous and discrete optimum algorithms based on the SUMT and genetic algorithms of this study.

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Application of multi-objective genetic algorithm for waste load allocation in a river basin (오염부하량 할당에 있어서 다목적 유전알고리즘의 적용 방법에 관한 연구)

  • Cho, Jae-Heon
    • Journal of Environmental Impact Assessment
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    • v.22 no.6
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    • pp.713-724
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    • 2013
  • In terms of waste load allocation, inequality of waste load discharge must be considered as well as economic aspects such as minimization of waste load abatement. The inequality of waste load discharge between areas was calculated with Gini coefficient and was included as one of the objective functions of the multi-objective waste load allocation. In the past, multi-objective functions were usually weighted and then transformed into a single objective optimization problem. Recently, however, due to the difficulties of applying weighting factors, multi-objective genetic algorithms (GA) that require only one execution for optimization is being developed. This study analyzes multi-objective waste load allocation using NSGA-II-aJG that applies Pareto-dominance theory and it's adaptation of jumping gene. A sensitivity analysis was conducted for the parameters that have significant influence on the solution of multi-objective GA such as population size, crossover probability, mutation probability, length of chromosome, jumping gene probability. Among the five aforementioned parameters, mutation probability turned out to be the most sensitive parameter towards the objective function of minimization of waste load abatement. Spacing and maximum spread are indexes that show the distribution and range of optimum solution, and these two values were the optimum or near optimal values for the selected parameter values to minimize waste load abatement.

A Load Balancing Technique Combined with Mean-Field Annealing and Genetic Algorithms (평균장 어닐링과 유전자 알고리즘을 결합한 부하균형기법)

  • Hong Chul-Eui;Park Kyeong-Mo
    • Journal of KIISE:Computer Systems and Theory
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    • v.33 no.8
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    • pp.486-494
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    • 2006
  • In this paper, we introduce a new solution for the load balancing problem, an important issue in parallel processing. Our heuristic load balancing technique called MGA effectively combines the benefit of both mean-field annealing (MFA) and genetic algorithms (GA). We compare the proposed MGA algorithm with other mapping algorithms (MFA, GA-l, and GA-2). A multiprocessor mapping algorithm simulation has been developed to measure performance improvement ratio of these algorithms. Our experimental results show that our new technique, the composition of heuristic mapping methods improves performance over the conventional ones, in terms of solution quality with a longer run time.

The Navigation Control for Intelligent Robot Using Genetic Algorithms (유전알고리즘을 이용한 지능형 로봇의 주행 제어)

  • Joo, Young-Hoon;Cho, Sang-Kyun
    • Journal of the Korean Institute of Intelligent Systems
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    • v.15 no.4
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    • pp.451-456
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    • 2005
  • In this paper, we propose the navigation control method for intelligent robot using messy genetic algorithm. The fuzzy controller design for navigation of the intelligent robot was dependant on expert's knowledge. But, the parameters of the fuzzy logic controller obtained from expert's control action may not be outimal. In this paper, to solve the above problem, we propose the identification method to automatically tune the number of fuzzy rule and parameters of memberships of fuzzy controller using mGA. Finally, to show and evaluate the generality and feasibility of the proposed method, we provides some simulations for wall following navigation of intelligent robot.

Design of Genetic Algorithm Processor(GAP) for Evolvable Hardware (진화하드웨어를 위한 유전자 알고리즘 프로세서(GAP) 설계)

  • Sim, Kwee-Bo;Kim, Tae-Hoon
    • Journal of the Korean Institute of Intelligent Systems
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    • v.12 no.5
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    • pp.462-466
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    • 2002
  • Genetic Algorithm (GA) which imitates the process of nature evolution is applied to various fields because it is simple to theory and easy to application. Recently applying GA to hardware, it is to proceed the research of Evolvable Hardware(EHW) developing the structure of hardware and reconstructing it. And it is growing a necessity of GAP that embodies the computation of GA to the hardware. Evolving by GA don't act in the software but in the hardware(GAP) will be necessary for the design of independent EHW. This paper shows the design GAP for fast reconfiguration of EHW.

SIMMER extension for multigroup energy structure search using genetic algorithm with different fitness functions

  • Massone, Mattia;Gabrielli, Fabrizio;Rineiski, Andrei
    • Nuclear Engineering and Technology
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    • v.49 no.6
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    • pp.1250-1258
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    • 2017
  • The multigroup transport theory is the basis for many neutronics modules. A significant point of the cross-section (XS) generation procedure is the choice of the energy groups' boundaries in the XS libraries, which must be carefully selected as an unsuitable energy meshing can easily lead to inaccurate results. This decision can require considerable effort and is particularly difficult for the common user, especially if not well-versed in reactor physics. This work investigates a genetic algorithm-based tool which selects an appropriate XS energy structure (ES) specific for the considered problem, to be used for the condensation of a fine multigroup library. The procedure is accelerated by results storage and fitness calculation speedup and can be easily parallelized. The extension is applied to the coupled code SIMMER and tested on the European Sustainable Nuclear Industrial Initiative (ESNII+) Advanced Sodium Technological Reactor for Industrial Demonstration (ASTRID)-like reactor system with different fitness functions. The results show that, when the libraries are condensed based on the ESs suggested by the algorithm, the code actually returns the correct multiplication factor, in both reference and voided conditions. The computational effort reduction obtained by using the condensed library rather than the fine one is assessed and is much higher than the time required for the ES search.

Initial Design Domain Reset Method for Genetic Algorithm with Parallel Processing

  • Lim, O-Kaung;Hong, Keum-Shik;Lee, Hyuk-Soo;Park, Eun-Ho
    • Journal of Mechanical Science and Technology
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    • v.18 no.7
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    • pp.1121-1130
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    • 2004
  • The Genetic Algorithm (GA), an optimization technique based on the theory of natural selection, has proven to be a relatively robust means of searching for global optimum. It converges to the global optimum point without auxiliary information such as differentiation of function. In the case of a complex problem, the GA involves a large population number and requires a lot of computing time. To improve the process, this research used parallel processing with several personal computers. Parallel process technique is classified into two methods according to subpopulation's size and number. One is the fine-grained method (FGM), and the other is the coarse-grained method (CGM). This study selected the CGM as a parallel process technique because the load is equally divided among several computers. The given design domain should be reduced according to the degree of feasibility, because mechanical system problems have constraints. The reduced domain is used as an initial design domain. It is consistent with the feasible domain and the infeasible domain around feasible domain boundary. This parallel process used the Message Passing Interface library.