• Title/Summary/Keyword: Genetic Approach

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Genetic Programming with Weighted Linear Associative Memories and its Application to Engineering Problems (가중 선형 연상기억을 채용한 유전적 프로그래밍과 그 공학적 응용)

  • 연윤석
    • Korean Journal of Computational Design and Engineering
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    • v.3 no.1
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    • pp.57-67
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    • 1998
  • Genetic programming (GP) is an extension of a genetic algoriths paradigm, deals with tree structures representing computer programs as individuals. In recent, there have been many research activities on applications of GP to various engineering problems including system identification, data mining, function approximation, and so forth. However, standard GP suffers from the lack of the estimation techniques for numerical parameters of the GP tree that is an essential element in treating various engineering applications involving real-valued function approximations. Unlike the other research activities, where nonlinear optimization methods are employed, I adopt the use of a weighted linear associative memory for estimation of these parameters under GP algorithm. This approach can significantly reduce computational cost while the reasonable accurate value for parameters can be obtained. Due to the fact that the GP algorithm is likely to fall into a local minimum, the GP algorithm often fails to generate the tree with the desired accuracy. This motivates to devise a group of additive genetic programming trees (GAGPT) which consists of a primary tree and a set of auxiliary trees. The output of the GAGPT is the summation of outputs of the primary tree and all auxiliary trees. The addition of auxiliary trees makes it possible to improve both the teaming and generalization capability of the GAGPT, since the auxiliary tree evolves toward refining the quality of the GAGPT by optimizing its fitness function. The effectiveness of this approach is verified by applying the GAGPT to the estimation of the principal dimensions of bulk cargo ships and engine torque of the passenger car.

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Genetic discrimination as another shadow of biotechnology (생명과학기술의 또 다른 그늘: 유전자차별)

  • Kim, Sang Hyun
    • Journal of Science and Technology Studies
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    • v.14 no.1
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    • pp.59-85
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    • 2014
  • This study aims to highlight the social aspects of genetic discrimination as another shadow that biotechnology can influence on social life. To do so, the definition of "genetic discrimination" and three perspectives (exceptionalism, expressivism, and human right discourse) were reviewed. In addition, the Genetic Information Nondiscrimination Act (GINA) of the United States and the Bioethics and Safety Act of Korea were analyzed. Several social implications for establishing the research and policies of genetic discrimination based on the existing research results of perceived genetic discrimination (the experiences, fears, and coping strategies of genetic discrimination) were suggested. These included public consensus on the definition of genetic discrimination and emphasis on a human rights approach against genetic discrimination; concerns regarding genetic discrimination in both the personal and public domains; raising the consciousness of both health care providers and the public regarding genetic discrimination; and developing psycho-social coping strategies for decreasing the fear of discrimination of asymptomatic people (hereditary carriers).

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Optimal Design of Robust Quantitative Feedback Controllers Using Linear Programming and Genetic Algorithms

  • Bokharaie, Vaheed S.;Khaki-Sedigh, Ali
    • 제어로봇시스템학회:학술대회논문집
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    • 2003.10a
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    • pp.428-432
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    • 2003
  • Quantitative Feedback Theory (QFT) is one of most effective methods of robust controller design and can be considered as a suitable method for systems with parametric uncertainties. Particularly it allows us to obtain controllers less conservative than other methods like $H_{\infty}$ and ${\mu}$-synthesis. In QFT method, we transform all the uncertainties and desired specifications to some boundaries in Nichols chart and then we have to find the nominal loop transfer function such that satisfies the boundaries and has the minimum high frequency gain. The major drawback of the QFT method is that there is no effective and useful method for finding this nominal loop transfer function. The usual approach to this problem involves loop-shaping in the Nichols chart by manipulating the poles and zeros of the nominal loop transfer function. This process now aided by recently developed computer aided design tools proceeds by trial and error and its success often depends heavily on the experience of the loop-shaper. Thus for the novice and First time QFT user, there is a genuine need for an automatic loop-shaping tool to generate a first-cut solution. In this paper, we approach the automatic QFT loop-shaping problem by using an algorithm involving Linear Programming (LP) techniques and Genetic Algorithm (GA).

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A Genetic Algorithm Based Task Scheduling for Cloud Computing with Fuzzy logic

  • Singh, Avtar;Dutta, Kamlesh
    • IEIE Transactions on Smart Processing and Computing
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    • v.2 no.6
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    • pp.367-372
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    • 2013
  • Cloud computing technology has been developing at an increasing expansion rate. Today most of firms are using this technology, making improving the quality of service one of the most important issues. To achieve this, the system must operate efficiently with less idle time and without deteriorating the customer satisfaction. This paper focuses on enhancing the efficiency of a conventional Genetic Algorithm (GA) for task scheduling in cloud computing using Fuzzy Logic (FL). This study collected a group of task schedules and assessed the quality of each task schedule with the user expectation. The work iterates the best scheduling order genetic operations to make the optimal task schedule. General GA takes considerable time to find the correct scheduling order when all the fitness function parameters are the same. GA is an intuitive approach for solving problems because it covers all possible aspects of the problem. When this approach is combined with fuzzy logic (FL), it behaves like a human brain as a problem solver from an existing database (Memory). The present scheme compares GA with and without FL. Using FL, the proposed system at a 100, 400 and 1000 sample size*5 gave 70%, 57% and 47% better improvement in the task time compared to GA.

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Traffic Signal Control with Fuzzy Membership Functions Generated by Genetic Algorithms (유전 알고리즘에 의해 생성된 퍼지 소속함수를 갖는 교통 신호 제어)

  • Kim, Jong-Wan;Kim, Byeong-Man;Kim, Ju-Youn
    • Journal of the Korean Institute of Intelligent Systems
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    • v.8 no.6
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    • pp.78-84
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    • 1998
  • In this paper, a fuzzy traffic controller using genetic algorithms is presented. Conventional fuzzy traffic controllers use membership functions generated by humans. However, this approach does not guarantee the optimal solution to design the fuzzy controller. Genetic algorithm is a good problem solving method requiring domain-specific knowledge that is often heuristic. To find fuzzy membership functions showing good performance, a fitness function must be defined. However it's not easy in traffic control to define such a function as a numeric expression. Thus, we use simulation approach, namely, the fitness value of a solution is determined by use of a performance measure that is obtained by traffic simulator. The proposed method outperforms the conventional fuzzy controllers.

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A New Approach to Multi-objective Error Correcting Code Design Method (다목적 Error Correcting Code의 새로운 설계방법)

  • Lee, Hee-Sung;Kim, Eun-Tai
    • Journal of the Korean Institute of Intelligent Systems
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    • v.18 no.5
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    • pp.611-616
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    • 2008
  • Error correcting codes (ECCs) are commonly used to protect against the soft errors. Single error correcting and double error detecting (SEC-DED) codes are generally used for this purpose. The proposed approach in this paper selectively reduced power consumption, delay, and area in single-error correcting, double error-detecting checker circuits that perform memory error correction. The multi-objective genetic algorithm is employed to solve the non -linear optimization problem. The proposed method allows that user can choose one of different non-dominated solutions depending on which consideration is important among them. Because we use multi-objective genetic algorithm, we can find various dominated solutions. Therefore, we can choose the ECC according to the important factor of the power, delay and area. The method is applied to odd-column weight Hsiao code which is well- known ECC code and experiments were performed to show the performance of the proposed method.

Design of a Tracking Gain-up Controller for the Vibration Suppression of Tracking Actuator (트랙킹 액추에이터의 진동 억제를 위한 트랙킹 Gain-up 제어기 설계)

  • Lee, Moonnoh;Jin, Kyoung Bog
    • Transactions of the Korean Society for Noise and Vibration Engineering
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    • v.23 no.4
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    • pp.356-364
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    • 2013
  • This paper presents a tracking gain-up controller design method to control effectively the vibration of tracking actuator caused by external shocks and remaining velocity after seek control. A pole placement constraint is considered to assure a desired transient response against the vibration of tracking actuator. A loop gain-up constraint is introduced to hold the tracking gain-up loop gain and control bandwidth within allowable bounds. The pole placement constraint is expressed by a matrix inequality and the loop gain-up constraint is considered as an objective function so that genetic algorithm can be applied. Finally, a tracking gain-up controller is obtained by integrating a genetic algorithm with LMI design approach. The proposed tracking gain-up controller design method is applied to the track-following system of a DVD recording device and its effectiveness is evaluated through the experimental results.

A Case Study of Human Resource Allocation for Effective Hotel Management

  • Murakami, Kayoko;Tasan, Seren Ozmehmet;Gen, Mitsuo;Oyabu, Takashi
    • Industrial Engineering and Management Systems
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    • v.10 no.1
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    • pp.54-64
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    • 2011
  • The purpose of this study is to optimally allocate the human resources to tasks while minimizing the total daily human resource costs and smoothing the human resource usage. The human resource allocation problem (hRAP) under consideration contains two kinds of special constraints, i.e. operational precedence and skill constraints in addition to the ordinary constraints. To deal with the multiple objectives and the special constraints, first we designed this hRAP as a network problem and then proposed a Pareto multistage decisionbased genetic algorithm (P-mdGA). During the evolutionary process of P-mdGA, a Pareto evaluation procedure called generalized Pareto-based scale-independent fitness function approach is used to evaluate the solutions. Additionally, in order to improve the performance of P-mdGA, we use fuzzy logic controller for fine-tuning of genetic parameters. Finally, in order to demonstrate the applicability and to evaluate the performance of the proposed approach, P-mdGA is applied to solve a case study in a hotel, where the managers usually need helpful automatic support for effectively allocating hotel staff to hotel tasks.

Dual Response Surface Optimization using Multiple Objective Genetic Algorithms (다목적 유전 알고리즘을 이용한 쌍대반응표면최적화)

  • Lee, Dong-Hee;Kim, Bo-Ra;Yang, Jin-Kyung;Oh, Seon-Hye
    • Journal of Korean Institute of Industrial Engineers
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    • v.43 no.3
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    • pp.164-175
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    • 2017
  • Dual response surface optimization (DRSO) attempts to optimize mean and variability of a process response variable using a response surface methodology. In general, mean and variability of the response variable are often in conflict. In such a case, the process engineer need to understand the tradeoffs between the mean and variability in order to obtain a satisfactory solution. Recently, a Posterior preference articulation approach to DRSO (P-DRSO) has been proposed. P-DRSO generates a number of non-dominated solutions and allows the process engineer to select the most preferred solution. By observing the non-dominated solutions, the DM can explore and better understand the trade-offs between the mean and variability. However, the non-dominated solutions generated by the existing P-DRSO is often incomprehensive and unevenly distributed which limits the practicability of the method. In this regard, we propose a modified P-DRSO using multiple objective genetic algorithms. The proposed method has an advantage in that it generates comprehensive and evenly distributed non-dominated solutions.

Optimization of Case-based Reasoning Systems using Genetic Algorithms: Application to Korean Stock Market (유전자 알고리즘을 이용한 사례기반추론 시스템의 최적화: 주식시장에의 응용)

  • Kim, Kyoung-Jae;Ahn, Hyun-Chul;Han, In-Goo
    • Asia pacific journal of information systems
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    • v.16 no.1
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    • pp.71-84
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    • 2006
  • Case-based reasoning (CBR) is a reasoning technique that reuses past cases to find a solution to the new problem. It often shows significant promise for improving effectiveness of complex and unstructured decision making. It has been applied to various problem-solving areas including manufacturing, finance and marketing for the reason. However, the design of appropriate case indexing and retrieval mechanisms to improve the performance of CBR is still a challenging issue. Most of the previous studies on CBR have focused on the similarity function or optimization of case features and their weights. According to some of the prior research, however, finding the optimal k parameter for the k-nearest neighbor (k-NN) is also crucial for improving the performance of the CBR system. In spite of the fact, there have been few attempts to optimize the number of neighbors, especially using artificial intelligence (AI) techniques. In this study, we introduce a genetic algorithm (GA) to optimize the number of neighbors to combine. This study applies the novel approach to Korean stock market. Experimental results show that the GA-optimized k-NN approach outperforms other AI techniques for stock market prediction.