• Title/Summary/Keyword: Inference system

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Structure Identification of Nonlinear System Using Adaptive Neuro-Fuzzy Inference Technique (적응 뉴로 퍼지추론 기법에 의한 비선형 시스템의 구조 동정에 관한 연구)

  • 이준탁;정형환;심영진;김형배;박영식
    • Proceedings of the Korean Institute of Intelligent Systems Conference
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    • 1996.10a
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    • pp.298-301
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    • 1996
  • This paper describes the structure Identification of nonlinear function using Adaptive Neuro-Fuzzy Inference Technique(ANFIS). Nonlinear mapping relationship between inputs and outputs were modeled by Sugeno-Takaki's Fuzzy Inference Method. Specially, the consequent parts were identified using a series of 1st order equations and the antecedent parts using triangular type membership function or bell type ones. According to learning Rules of ANFIS, adjustable parameters were converged rapidly and accurately.

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A hierarchical fuzzy controller using structured Takagi-Sugeno type fuzzy inference engine

  • Moon G. Joo;Lee, Jin S.
    • 제어로봇시스템학회:학술대회논문집
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    • 1998.10a
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    • pp.179-184
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    • 1998
  • In this paper, a new hierarchical fuzzy inference system (HFIS) using structured Takagi-Sugeno type fuzzy inference units(FIUs) is proposed. The proposed HFIS not only solves the rule explosion problem in conventional HFIS, but also overcomes the readability problem caused by the structure where outputs of previous level FIUs are used as input variables directly. Gradient descent algorithm is used for adaptation of fuzzy rules. The ball and beam control is performed in computer simulation to illustrate the performance of the proposed controller.

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Determination of dosing rate for water treatment using fusion of genetic algorithms and fuzzy inference system (유전알고리즘과 퍼지추론시스템의 합성을 이용한 정수처리공정의 약품주입률 결정)

  • 김용열;강이석
    • 제어로봇시스템학회:학술대회논문집
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    • 1996.10b
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    • pp.952-955
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    • 1996
  • It is difficult to determine the feeding rate of coagulant in water treatment process, due to nonlinearity, multivariables and slow response characteristics etc. To deal with this difficulty, the fusion of genetic algorithms and fuzzy inference system was used in determining of feeding rate of coagulant. The genetic algorithms are excellently robust in complex operation problems, since it uses randomized operators and searches for the best chromosome without auxiliary information from a population consists of codings of parameter set. To apply this algorithms, we made the look up table and membership function from the actual operation data of water treatment process. We determined optimum dosages of coagulant (PAC, LAS etc.) by the fuzzy operation, and compared it with the feeding rate of the actual operation data.

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Prototyping of Knowledge-Based Systems for Field Inspection and Safety Assessment of RC Bridges (RC 교량의 현장 안전진단을 위한 지식기반시스템의 원형개발)

  • Hwang, Jin-Ha;Park, Jong-Hoi;An, Seoung-Su;Kim, Ki-Hyun
    • Journal of the Korea institute for structural maintenance and inspection
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    • v.6 no.3
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    • pp.185-192
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    • 2002
  • Prototyping for field inspection safety assessment expert system of bridge structures is presented in this paper. Knowledgebase with production rules is constructed using the semiautomatic method on the basis of bridge inspection manuals and working reports of the related agency. Backward inference method is taken with the aids of external shells as a inference engine of knowledge-based systems. Implementation of the developed prototype system on MS Windows98 will shows inspiring aspects useful to guide and standardize the field works. In the case to be reinforced with abundant knowledge bases, this will be expected to be educate the practicing engineers.

Fuzzy inference based cover thickness estimation of reinforced concrete structure quantitatively considering salty environment impact

  • Do, Jeong-Yun
    • Computers and Concrete
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    • v.3 no.2_3
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    • pp.145-161
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    • 2006
  • This article involves architecting prototype-fuzzy expert system for designing the nominal cover thickness by means of fuzzy inference for quantitatively representing the environment affecting factor to reinforced concrete in chloride-induced corrosion environment. In this work, nominal cover thickness to reinforcement in concrete was determined by the sum of minimum cover thickness and tolerance to that defined from skill level, constructability and the significance of member. Several variables defining the quality of concrete and environment affecting factor (EAF) including relative humidity, temperature, cyclic wet and dry, and the distance from coast were treated as fuzzy variables. To qualify EAF the environment conditions of cycle degree of wet-dry, relative humidity, distance from coast and temperature were used as input variables. To determine the nominal cover thickness a qualified EAF, concrete grade, and watercement ratio were used. The membership functions of each fuzzy variable were generated from the engineering knowledge and intuition based on some references as well as some international codes of practice.

Double Gate MOSFET Modeling Based on Adaptive Neuro-Fuzzy Inference System for Nanoscale Circuit Simulation

  • Hayati, Mohsen;Seifi, Majid;Rezaei, Abbas
    • ETRI Journal
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    • v.32 no.4
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    • pp.530-539
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    • 2010
  • As the conventional silicon metal-oxide-semiconductor field-effect transistor (MOSFET) approaches its scaling limits, quantum mechanical effects are expected to become more and more important. Accurate quantum transport simulators are required to explore the essential device physics as a design aid. However, because of the complexity of the analysis, it has been necessary to simulate the quantum mechanical model with high speed and accuracy. In this paper, the modeling of double gate MOSFET based on an adaptive neuro-fuzzy inference system (ANFIS) is presented. The ANFIS model reduces the computational time while keeping the accuracy of physics-based models, like non-equilibrium Green's function formalism. Finally, we import the ANFIS model into the circuit simulator software as a subcircuit. The results show that the compact model based on ANFIS is an efficient tool for the simulation of nanoscale circuits.

Study on Mobile Robot's Navigation Problem Using Jacobian and Fuzzy Inference System (자코비안과 퍼지 추론 시스템을 이용한 이동로봇의 주행문제에 관한 연구)

  • Choi Gyu-Jong;Ahn Doo-Sung
    • Journal of Institute of Control, Robotics and Systems
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    • v.12 no.6
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    • pp.554-560
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    • 2006
  • In this paper, we propose the topological map building method about unknown environment using the ultrasonic sensors. An ultrasonic sensor inherently has the range error due to the specular reflection. To decrease this error, we estimate the obstacle states(position and velocity) using the local minimum sensor values and Jacobian. Estimated states are used to avoid the obstacles and build the topological map similar to the type that human being memorizes an environment. When a mobile robot is faced with three problems(comer way, cross way and dead end), it senses the movable directions using FIS(Fuzzy Inference System). Among these directions, it can select the target direction using binary decision tree(Turn Side Selector). Proposed algorithm has been verified with three simulations and three implementations.

A Nutrition Evaluation System Based on Hierarchical Fuzzy Approach

  • Son, Chang-S.;Jeong, Gu-Beom
    • International Journal of Fuzzy Logic and Intelligent Systems
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    • v.8 no.2
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    • pp.87-93
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    • 2008
  • In this paper, we propose a hierarchical fuzzy based nutrition evaluation system that can analyze the individuals' nutrition status through the inference results generated by each layer. Moreover, a method to minimize the uncertainty of inference in the evaluated nutrition status is discussed. To show the effect of the uncertainty in fuzzy inference, we compared the results of nutrition evaluation with/without the certainty factor of rules on 132 people over the age of 65. From the experimental results, we can see that the evaluation method with the modified certainty factor provides better reliability than that of the general evaluation method without the certainty factor.

A study on Adaptive Dynamic Matirx Control of a Boiler-Turbine System (보일러 터빈 시스템의 적응 동역학 행렬 제어에 관한 연구)

  • Oh, Seok-Ho;Moon, Un-Chul;Lee, Seung-Chul
    • Proceedings of the KIEE Conference
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    • 2007.07a
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    • pp.1638-1639
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    • 2007
  • This paper proposes an adaptive Dynamic Matrix Control (DMC) using Fuzzy Inference and its application to boiler-turbine system. Nine Step Response Models (SRM) at various operating points are represented as fuzzy inference rules. On-line fuzzy inference is performed at every sampling step to find the suitable SRM. Therefore, the proposed adaptive DMC can consider the nonlinearity of boiler-turbine system.

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Rule-based Named Entity (NE) Recognition from Speech (음성 자료에 대한 규칙 기반 Named Entity 인식)

  • Kim Ji-Hwan
    • MALSORI
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    • no.58
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    • pp.45-66
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    • 2006
  • In this paper, a rule-based (transformation-based) NE recognition system is proposed. This system uses Brill's rule inference approach. The performance of the rule-based system and IdentiFinder, one of most successful stochastic systems, are compared. In the baseline case (no punctuation and no capitalisation), both systems show almost equal performance. They also have similar performance in the case of additional information such as punctuation, capitalisation and name lists. The performances of both systems degrade linearly with the number of speech recognition errors, and their rates of degradation are almost equal. These results show that automatic rule inference is a viable alternative to the HMM-based approach to NE recognition, but it retains the advantages of a rule-based approach.

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