• Title/Summary/Keyword: Fuzzy Logic Model

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Temeperature control method of refrigerator using fuzzy logic controller (퍼지 로직 제어기를 이용한 냉장고 온도 제어 방법)

  • 최병준;한상완;홍석교
    • 제어로봇시스템학회:학술대회논문집
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    • 1997.10a
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    • pp.28-31
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    • 1997
  • This paper describes the quick and precise controlling method for home-applied refrigerator. The proposed controller is based on the fuzzy logic control method and is designed for better performance in maintaining the constant temperature of the refrigerator. The temperature of the refrigerator is controlled by the cooling air blowing fan motor which is put on, off according to fuzzy logic controller. Finally, I study the performance of the proposed controller through the computer simulation about the approximated model of the refrigerator.

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Traffic Fuzzy Control : Software and Hardware Implementations

  • Jamshidi, M.;Kelsey, R.;Bisset, K.
    • Proceedings of the Korean Institute of Intelligent Systems Conference
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    • 1993.06a
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    • pp.907-910
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    • 1993
  • This paper describes the use of fuzzy control and decision making to simulate the control of traffic flow at an intersection. To show the value of fuzzy logic as an alternative method for control of traffic environments. A traffic environment includes the lanes to and from an intersection, the intersection, vehicle traffic, and signal lights in the intersection. To test the fuzzy logic controller, a computer simulation was constructed to model a traffic environment. A typical cross intersection was chosen for the traffic environment, and the performance of the fuzzy logic controller was compared with the performance of two different types of conventional control. In the hardware verifications, fuzzy logic was used to control acceleration of a model train on a circular path. For the software experiment, the fuzzy logic controller proved better than conventional control methods, especially in the case of highly uneven traffic flow between different directions. On the hardware si e of the research, the fuzzy acceleration control system showed a marked improvement in smoothness of ride over crisp control.

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Adaptive Fuzzy Control for High Performance Speed Controller in PMSM Drive (PMSM 드라이브의 고성능 속도제어를 위한 적응 퍼지제어기)

  • Chung, Dong-Hwa;Lee, Jung-Chul;Lee, Hong-Gyun;Jung, Tack-Gi
    • Proceedings of the KIEE Conference
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    • 2002.04a
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    • pp.79-81
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    • 2002
  • This paper develops a adaptive fuzzy controller based fuzzy logic control for high performance speed controller in permanent magnet synchronous motor(PMSM) drives. In the proposed system, fuzzy control is used to implement the direct controller as well as the adaptation mechanism. The operation of the direct fuzzy controller and the fuzzy logic based adaptation mechanism is studied. A model reference adaptive scheme is proposed in which the adaptation mechanism is executed by fuzzy logic based on the error and change of error measured between the motor speed and output of a reference model. The control performance of the adaptive fuzzy controller is evaluated by simulation for various operating conditions. The validity of the proposed adaptive fuzzy controller is confirmed by performance results for PMSM drive system.

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Fuzzy Logic in Nuclear Safety Issues

  • Ruan, Da
    • Journal of the Korean Institute of Intelligent Systems
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    • v.7 no.1
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    • pp.34-44
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    • 1997
  • The Belgian Nuclear Research Centre(SCK${\cdot}$CEN) has been a pioneer of the peaceful uses of nuclear energy after over forty years of existence. Recently, SCK${\cdot}$CEN's financial support of doctoral and postdoctoral research in close collaboration with universities has been a vital ingredient for securing a quality profile committed to the pursuit of execllence. FLINS, Fuzzy Logic and Intelligent technologies in Nuclear Science, was initially built within one of the postdoctoral research project at SCK${\cdot}$CEN. Among SCK${\cdot}$CEN's activities which will have an important impact on its scientific future, the application of fuzzy logic and intelligent technologies in nuclear science and engineering opens new domains in radiation protection, safety assessment, human reliability, nuclear reactor control, waste and disposal, etc. In this paper, we review the available literature on fuzzy logic in nuclear applications. We then present the initiative of R&D on fuzzy logic applications at SCK${\cdot}$CEN, namely, (1) safety control for a nuclear reactor, and (2) a safety evaluation model for nuclear transmission lines. By these two examples of nuclear applications, we illustrate the potential use of fuzzy logic in nuclear safety issues.

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Fuzzy logic model for the prediction of concrete compressive strength by incorporating green foundry sand

  • Rashid, Khuram;Rashid, Tabasam
    • Computers and Concrete
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    • v.19 no.6
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    • pp.617-623
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    • 2017
  • This work is conducted with the aim of using waste material to reserve the natural resources. The objective is accomplished by conducting experimentation and verify by modeling based on fuzzy logic. In experimentation, concrete is casted by using natural/river sand as fine aggregate and termed as control specimen. Natural sand is conserved by replacing it with used foundry sand (UFS) by an amount of 10, 20 and 30% by weight. Fresh and hardened properties of concrete are investigated at different ages. It is observed that compressive strength and modulus of elasticity reduced with the increase in amount of UFS. Furthermore, concrete compressive strength is predicted by using fuzzy logic model and verified at different replacement ratio and age with experimental observations.

A Construction of Fuzzy Inference Network based on Neural Logic Network and its Search Strategy

  • Lee, Mal-rey
    • Proceedings of the Korea Society for Industrial Systems Conference
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    • 2000.11a
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    • pp.375-389
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    • 2000
  • Fuzzy logic ignores some information in the reasoning process. Neural networks are powerful tools for the pattern processing, but, not appropriate for the logical reasoning. To model human knowledge, besides pattern processing capability, the logical reasoning capability is equally important. Another new neural network called neural logic network is able to do the logical reasoning. Because the fuzzy inference is a fuzzy logical reasoning, we construct fuzzy inference network based on the neural logic network, extending the existing rule- inference. network. And the traditional propagation rule is modified. For the search strategies to find out the belief value of a conclusion in the fuzzy inference network, we conduct a simulation to evaluate the search costs for searching sequentially and searching by means of search priorities.

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Fuzzy Servo Design for Electromechanical System

  • Lee, Han-Sik
    • Journal of the Korean Institute of Intelligent Systems
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    • v.5 no.2
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    • pp.79-85
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    • 1995
  • In this paper, a fuzzy logic is applied to a model-following control(MFC) to form a fuzzy model following control(FMFC). The feedback gain the MFC is adjusted continuously through the fuzzy logic rule. The proposed fuzzy-MFC is applied to synthesize controllers for linear time inveriant(LTI) systems with parameter uncertainties, and the robustness results of the proposed designs are compared.

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Control of Glucose Concentration in a Fed-Batch Cultivation of Scutellaria baicalensis G. Plant Cells a Self-Organizing Fuzzy Logic Controller

  • Choi, Jeong-Woo;Cho, Jin-Man;Kim, Young-Kee;Park, Soo-Yong;Kim, Ik-Hwan
    • Journal of Microbiology and Biotechnology
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    • v.11 no.5
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    • pp.739-748
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    • 2001
  • A self-organizing fuzzy logic controller using a genetic algorithm is described, which controlled the glucose concentration for the enhancement of flavonoid production in a fed-batch cultivation of Scutellaria baicalensis G. plant cells. The substrate feeding strategy in a fed-batch culture was to increase the flavonoid production by using the proposed kinetic model. For the two-stage culture, the substrate feeding strategy consisted of a first period with 28 g/I of glucose to promote cell growth, followed by a second period with 5 g/I of glucose to promote flavonoid production. A simple fuzzy logic controller and the self-organizing fuzzy logic controller using a genetic algorithm was constructed to control the glucose concentration in a fed-batch culture. The designed fuzzy logic controllers were applied to maintain the glucose concentration at given set-points of the two-stage culture in fed-batch cultivation. The experimental results showed that the self-organizing fuzzy logic controller improved the controller\`s performance, compared with that of the simple fuzzy logic controller. The specific production yield and productivity of flavonoids in the two-stage culture were higher than those in the batch culture.

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Incorporation of Fuzzy Theory with Heavyweight Ontology and Its Application on Vague Information Retrieval for Decision Making

  • Bukhari, Ahmad C.;Kim, Yong-Gi
    • International Journal of Fuzzy Logic and Intelligent Systems
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    • v.11 no.3
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    • pp.171-177
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    • 2011
  • The decision making process is based on accurate and timely available information. To obtain precise information from the internet is becoming more difficult due to the continuous increase in vagueness and uncertainty from online information resources. This also poses a problem for blind people who desire the full use from online resources available to other users for decision making in their daily life. Ontology is considered as one of the emerging technology of knowledge representation and information sharing today. Fuzzy logic is a very popular technique of artificial intelligence which deals with imprecision and uncertainty. The classical ontology can deal ideally with crisp data but cannot give sufficient support to handle the imprecise data or information. In this paper, we incorporate fuzzy logic with heavyweight ontology to solve the imprecise information extraction problem from heterogeneous misty sources. Fuzzy ontology consists of fuzzy rules, fuzzy classes and their properties with axioms. We use Fuzzy OWL plug-in of Protege to model the fuzzy ontology. A prototype is developed which is based on OWL-2 (Web Ontology Language-2), PAL (Protege Axiom Language), and fuzzy logic in order to examine the effectiveness of the proposed system.

A Study on the Optimal Design Fuzzy Type Stabilizing Controller Using Genetic Algorithm (유전 알고리즘을 이용한 퍼지형 안정화 제어기의 최적설계에 관한 연구)

  • Lee, Heung-Jae;Lim, Chan-Ho;Yoon, Byong-Gyu
    • Proceedings of the KIEE Conference
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    • 1998.11a
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    • pp.326-328
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    • 1998
  • This paper presents an optimal fuzzy power system stabilizer to damp out low frequency oscillation. The fuzzy logic controllers has been applied to a power system stabilizing controllers. But the design of a fuzzy logic power system stabilizer relies on empirical and heuristic knowledge of human experts as well as many trial-and-errors in general. This paper presents the optimal design method of the fuzzy logic stabilizer using the genetic algorithm, which is the optimization method based on the mechanics of natural selection and natural genetics. The proposed method tunes the parameters of the fuzzy logic stabilizer in order to minimize the consuming time during the design process. In this paper, the proposed method tunes the shape of membership function of the fuzzy variables. The proposed system is applied to the one-machine infinite-bus model of a power system. Through the case study, the efficiency of the fuzzy stabilizing controller tuned by genetic algorithm is verified.

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