• 제목/요약/키워드: Genetic techniques

검색결과 744건 처리시간 0.025초

Handwritten Digit Recognition with Softcomputing Techniques

  • Cho, Sung-Bae
    • 한국지능시스템학회:학술대회논문집
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    • 한국퍼지및지능시스템학회 1998년도 The Third Asian Fuzzy Systems Symposium
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    • pp.707-712
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    • 1998
  • This paper presents several softcomputing techniques such as neural networks, fuzzy logic and genetic algorithms : Neural networks as brain metaphor provide fundamental structure, fuzzy logic gives a possibility to utilize top-down knowledge from designer, and genetic algorithms as evolution metaphor determine several system parameters with the process of bottom up development. With these techniques, we develop a pattern recognizer which consists of multiple neural networks aggregated by fuzzy integral in which genetic algorithms determine the fuzzy density values. The experimental results with the problem of recognizing totally unconstrained handwritten numeral show that the performance of the proposed method is superior to that of conventional methods.

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A brief review of penalty methods in genetic algorithms for optimization

  • Gen, Mitsuo;Cheng, Runwei
    • 한국경영과학회:학술대회논문집
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    • 대한산업공학회/한국경영과학회 1996년도 춘계공동학술대회논문집; 공군사관학교, 청주; 26-27 Apr. 1996
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    • pp.30-35
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    • 1996
  • Penalty technique perhaps is the most common technique used in the genetic algorithms for constrained optimization problems. In recent years, several techniques have been proposed in the area of evolutionary computation. However, there is no general guideline on designing penalty function and constructing an efficient penalty function is quite problem-dependent. The purpose of the paper is to give a tutorial survey of recent works on penalty techniques used in genetic algorithms and to give a better classification on exisitng works, which may be helpful for revealing the intrinsic relationship among them and for providing some hints for further studies on penalty techniques.

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유전자 알고리즘 기반의 기업부실예측 통합모형 (Integrated Corporate Bankruptcy Prediction Model Using Genetic Algorithms)

  • 옥중경;김경재
    • 지능정보연구
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    • 제15권4호
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    • pp.99-121
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    • 2009
  • 최근 데이터마이닝 기법을 이용하여 기업의 부실을 예측하고자 하는 연구가 많이 이루어져 왔다. 여러 연구자들에 의해 다양한 데이터마이닝 기법이 연구되었으나 각 방법론이 장단점을 가지고 있기에 이를 보완적으로 사용하고자하는 결합기법에 대한 연구도 꾸준하게 발표되고 있다. 본 연구에서는 데이터마이닝 기법을 각 기법의 특성을 바탕으로 4가지 형태로 구분하고 각 형태의 대표적인 기법을 선택하여 이를 유전자알고리즘을 통하여 통합하는 기법을 제안한다. 유전자알고리즘은 전역최적화기법으로 다양한 기법의 결과를 유기적으로 통합하여 최적해 또는 유사최적해를 찾게 해 줄 것이다. 본 연구에서는 기업부실예측에서 유용한 모형을 찾기 위하여 단일모형, 기존의 통합모형과 본 연구에서 제안하는 유전자알고리즘 통합기법의 결과를 비교한다.

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An Efficient Low Complexity Blind Equalization Using Micro-Genetic Algorithm

  • Kim, Sung-Soo;Kang, Jee-Hye
    • International Journal of Fuzzy Logic and Intelligent Systems
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    • 제4권3호
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    • pp.283-287
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    • 2004
  • In this paper, a method of designing the efficient batch blind equalization with low complexity using a micro genetic algorithm (GA), is presented. In general, the blind equalization techniques that are focused on the complexity reduction might be carried out with minor effect on the performance. Among the advanced various subjects in the field of GAs, a micro genetic algorithm is employed to identity the unknown channel impulse response in order to reduce the search space effectively. A new cost function with respect to the constant modulus criterion is suggested considering its relation to the Wiener criterion. We provide simulation results to show the superiority of the proposed techniques compared to other existing techniques.

Genetic Manipulation and Transformation Methods for Aspergillus spp.

  • Son, Ye-Eun;Park, Hee-Soo
    • Mycobiology
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    • 제49권2호
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    • pp.95-104
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    • 2021
  • Species of the genus Aspergillus have a variety of effects on humans and have been considered industrial cell factories due to their prominent ability for manufacturing several products such as heterologous proteins, secondary metabolites, and organic acids. Scientists are trying to improve fungal strains and re-design metabolic processes through advanced genetic manipulation techniques and gene delivery systems to enhance their industrial efficiency and utility. In this review, we describe the current status of the genetic manipulation techniques and transformation methods for species of the genus Aspergillus. The host strains, selective markers, and experimental materials required for the genetic manipulation and fungal transformation are described in detail. Furthermore, the advantages and disadvantages of these techniques are described.

Comparison of Particle Swarm Optimization and the Genetic Algorithm in the Improvement of Power System Stability by an SSSC-based Controller

  • Peyvandi, M.;Zafarani, M.;Nasr, E.
    • Journal of Electrical Engineering and Technology
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    • 제6권2호
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    • pp.182-191
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    • 2011
  • Genetic algorithms (GA) and particle swarm optimization (PSO) are the most famous optimization techniques among various modern heuristic optimization techniques. These two approaches identify the solution to a given objective function, but they employ different strategies and computational effort; therefore, a comparison of their performance is needed. This paper presents the application and performance comparison of the PSO and GA optimization techniques for a static synchronous series compensator-based controller design. The design objective is to enhance power system stability. The design problem of the FACTS-based controller is formulated as an optimization problem, and both PSO and GA optimization techniques are employed to search for the optimal controller parameters.

Recent progress in using Drosophila as a platform for human genetic disease research

  • Wan Hee Yoon
    • Journal of Genetic Medicine
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    • 제20권2호
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    • pp.39-45
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    • 2023
  • As advanced sequencing technologies continue to uncover an increasing number of variants in genes associated with human genetic diseases, there is a growing demand for systematic approaches to assess the impact of these variants on human development, health, and disease. While in silico analyses have provided valuable insights, it is essential to complement these findings with model organism studies to determine the functional consequences of genetic variants in vivo. Drosophila melanogaster is an excellent genetic model for such functional studies due to its efficient genetic technologies, high gene conservation with humans, accessibility to mutant fly resources, short life cycles, and cost-effectiveness. The traditional GAL4-UAS system, allowing precise control of gene expression through binary regulation, is frequently employed to assess the effects of monoallelic variants. Recombinase medicated cassette exchange or CRISPR-Cas9-mediated GAL4 insertion within coding introns or substitution of gene body with Kozak-Gal4 result in the loss-of-function of the target gene. This GAL4 insertion strategy also enables the expression of reference complementary DNA (cDNA) or cDNA carrying genetic variants under the control of endogenous regulatory cis elements. Furthermore, the CRISPR-Cas9-directed tissue-specific knockout and cDNA rescue system provides the flexibility to investigate candidate variants in a tissue-specific and/or developmental-timing dependent manner. In this review, we will delve into the diverse genetic techniques available in Drosophila and their applications in diagnosing and studying numerous undiagnosed diseases over the past decade.

Optimizing SVM Ensembles Using Genetic Algorithms in Bankruptcy Prediction

  • Kim, Myoung-Jong;Kim, Hong-Bae;Kang, Dae-Ki
    • Journal of information and communication convergence engineering
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    • 제8권4호
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    • pp.370-376
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    • 2010
  • Ensemble learning is a method for improving the performance of classification and prediction algorithms. However, its performance can be degraded due to multicollinearity problem where multiple classifiers of an ensemble are highly correlated with. This paper proposes genetic algorithm-based optimization techniques of SVM ensemble to solve multicollinearity problem. Empirical results with bankruptcy prediction on Korea firms indicate that the proposed optimization techniques can improve the performance of SVM ensemble.

유전과 기울기 최적화기법을 이용한 퍼지 파라메터의 자동 생성 (Automatic generation of Fuzzy Parameters Using Genetic and gradient Optimization Techniques)

  • 유동완;라경택;전순용;서보혁
    • 대한전기학회:학술대회논문집
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    • 대한전기학회 1998년도 하계학술대회 논문집 B
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    • pp.515-518
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    • 1998
  • This paper proposes a new hybrid algorithm for auto-tuning fuzzy controllers improving the performance. The presented algorithm estimates automatically the optimal values of membership functions, fuzzy rules, and scaling factors for fuzzy controllers, using a genetic-MGM algorithm. The object of the proposed algorithm is to promote search efficiency by a genetic and modified gradient optimization techniques. The proposed genetic and MGM algorithm is based on both the standard genetic algorithm and a gradient method. If a maximum point don't be changed around an optimal value at the end of performance during given generation, the genetic-MGM algorithm searches for an optimal value using the initial value which has maximum point by converting the genetic algorithms into the MGM(Modified Gradient Method) algorithms that reduced the number of variables. Using this algorithm is not only that the computing time is faster than genetic algorithm as reducing the number of variables, but also that can overcome the disadvantage of genetic algorithms. Simulation results verify the validity of the presented method.

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Prediction of the price for stock index futures using integrated artificial intelligence techniques with categorical preprocessing

  • Kim, Kyoung-jae;Han, Ingoo
    • 한국경영과학회:학술대회논문집
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    • 한국경영과학회 1997년도 추계학술대회발표논문집; 홍익대학교, 서울; 1 Nov. 1997
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    • pp.105-108
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    • 1997
  • Previous studies in stock market predictions using artificial intelligence techniques such as artificial neural networks and case-based reasoning, have focused mainly on spot market prediction. Korea launched trading in index futures market (KOSPI 200) on May 3, 1996, then more people became attracted to this market. Thus, this research intends to predict the daily up/down fluctuant direction of the price for KOSPI 200 index futures to meet this recent surge of interest. The forecasting methodologies employed in this research are the integration of genetic algorithm and artificial neural network (GAANN) and the integration of genetic algorithm and case-based reasoning (GACBR). Genetic algorithm was mainly used to select relevant input variables. This study adopts the categorical data preprocessing based on expert's knowledge as well as traditional data preprocessing. The experimental results of each forecasting method with each data preprocessing method are compared and statistically tested. Artificial neural network and case-based reasoning methods with best performance are integrated. Out-of-the Model Integration and In-Model Integration are presented as the integration methodology. The research outcomes are as follows; First, genetic algorithms are useful and effective method to select input variables for Al techniques. Second, the results of the experiment with categorical data preprocessing significantly outperform that with traditional data preprocessing in forecasting up/down fluctuant direction of index futures price. Third, the integration of genetic algorithm and case-based reasoning (GACBR) outperforms the integration of genetic algorithm and artificial neural network (GAANN). Forth, the integration of genetic algorithm, case-based reasoning and artificial neural network (GAANN-GACBR, GACBRNN and GANNCBR) provide worse results than GACBR.

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