• Title/Summary/Keyword: fuzzy 추론

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Obesity Evaluation System using Fuzzy Inference (퍼지추론을 이용한 비만평가 시스템)

  • Jeong Gu-Beom;Kim Doo-Ywan
    • Journal of Internet Computing and Services
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    • v.4 no.2
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    • pp.61-67
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    • 2003
  • It has recently become known that the social issue of obesity, caused by increased caloric intake and lack of exercise, is a risk factor in the cause of various adult diseases. Above all, to prevent or cure obesity, we must accurately evaluate the degree of obesity, and we have used BML, WHR, and waist measurements for this purpose. In this paper, we propose an obesity evaluation system based on fuzzy inference using BML and waist measurement. For this purpose, we decided reasoning rule and membership function about BML and waist measurements. The inference result is presented in a descriptive sentence.

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The Method of Effective Inference Using Rough Set and Fuzzy Naive Bayes Theory (러프집합과 퍼지 네이브 베이스 이론을 이용한 효율적인 추론 방법)

  • Hwang Jeong-Sik;Son Chang-Sik;Chung Hwan-Mook
    • Proceedings of the Korean Institute of Intelligent Systems Conference
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    • 2005.11a
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    • pp.117-120
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    • 2005
  • 퍼지 규칙 기반 시스템에서 분류 및 경계를 결정하기 위한 방법으로 퍼지 규칙을 학습하는 다양한 방법들이 제안되고 있다. 그리고 추론 규칙간의 상관성을 고려하여 불필요한 속성을 제거함으로써 좀 더 효율적인 추론 결과를 얻을 수 있다. 따라서 본 논문에서는 퍼지 규칙 기반 시스템에서 각 규칙에 따른 결정 테이블를 작성하고 러프집합을 이용하여 불필요한 속성을 제거하였으며 규칙의 확신도에 퍼지 네이브 베이스 이론을 적용한 추론 방법을 제안한다.

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Fuzzy-Inference Control of a PWM Inverter for 400 Hz AC Voltage Regulation (400 Hz AC 전압용 PWM 인버터의 퍼지추론 제어)

  • Lee, Man Hee;Song, Jae Ik;Lee, Kang Woong
    • Journal of Advanced Navigation Technology
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    • v.3 no.1
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    • pp.44-51
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    • 1999
  • In this paper we proposed an output voltage regulation scheme of a single-phase PWM inverter used to obtain a 400 Hz sinusoidal AC voltage for an aircraft. The fuzzy-inference control scheme is designed to achieve good output voltage tracking in the presence of load change or parameter variations. The PWM gate signals are determined by the fuzzy-inference controller using the error between the reference voltage and the feedback voltage and the derivative of error. The tracking performance of.

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Comparison of Fuzzy Implication Operators using Automated Reasoning (자동화된 추론을 이용한 퍼지 조건연산자의 비교 분석)

  • 김용기
    • Journal of the Korean Institute of Intelligent Systems
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    • v.5 no.4
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    • pp.18-32
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    • 1995
  • Fuzzy rules, developed by experts thus far, may be often inconsistent and incomplete. This paper proposes a new methodology for automatic generation of fuzzy rules which are nearly complete and not inconsistent. This is accomplished by simulating a knowledge gathering process of humans from control experiences. This method is simpler and more efficient than existing ones. It is shown through simulation that our method even generates better rules than those generated by experts, under fine tuned parameters.

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Implementation of a Fuzzy PI+PD Controller for DC Servo Systems (직류 서보시스템 제어용 퍼지 PI+PD 제어기 로직회로 구현)

  • Hong, Soon-Ill;Hong, Jeng-Pyo;Jung, Sung-Hwan
    • Journal of Advanced Marine Engineering and Technology
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    • v.33 no.8
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    • pp.1246-1253
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    • 2009
  • This paper presents derived a calculating form of fuzzy inference, based on decomposition of $\alpha$-level sets. Based on the calculating form it is propose that fuzzy logic circuits of PI+PD controller are a body from fuzzy inference to defuzzificaion in cases where the command variable u directly is generated PWM. The effect of quantization on $\alpha$-levels is investigated. with input/out characteristics of fuzzy controller by simulation. It is concluded that 4 quantization levels are sufficient result for fuzzy control performance of DC servo system. Simulation and experimental results demonstrated that the hardware implementation of the proposed controller can successfully provide good performance on the position control of DC servo system.

Effective Recognition of Land Registration Map Using Fuzzy Inference (퍼지추론 기반의 효율적인 지적도면 인식)

  • Kim, Yoon-Ho
    • Journal of Advanced Navigation Technology
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    • v.11 no.3
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    • pp.343-349
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    • 2007
  • This paper addressed a recognition method of land registration map based on fuzzy inference scheme, which is able to solve the time complexity problem of typical method [Fig. 2]. Not only line color, thickness but also number, character are used as a fuzzy input parameter. It concentrated on generation of fuzzy association map, and useful informations are extracted result from fuzzy inference. These results are precedent process for estimating the construction space and restoring 3D automatic modeling. It can also utilize to the internet service acceleration propulsion business such as u-Gov based land registration service.

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A Study on Reasoning and Learning of Fuzzy Rules Using Neural Networks (신경회로망을 이용한 퍼지룰의 추론과 학습에 관한 연구)

  • 이계호;임영철;김이곤;조경영
    • The Journal of Korean Institute of Communications and Information Sciences
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    • v.18 no.2
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    • pp.231-238
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    • 1993
  • A rules of fuzzy control is to represent an expert‘s and engineer‘s ambiguous control knowledge of system with some lingustic rules. This rule is very difficult to represent perfectly because expert‘s knowledge is not precise and the rule is not perfect. We propose the fuzzy reasoning and learning to upgrade precision of imperfect rules successively after system running. In the proposed method, the precision of the backward part of a fuzzy rule is improved by back propagation learning method. Also, the method reasons the compatibility degree of the forward part of fuzzy rule by associative memory method. This method this is successfully applied to design auto-parking fuzzy controller in which expert‘s technology and knowledge are required in the limited area.

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Learning and inference of fuzzy inference system with fuzzy neural network (퍼지 신경망을 이용한 퍼지 추론 시스템의 학습 및 추론)

  • 장대식;최형일
    • Journal of the Korean Institute of Telematics and Electronics B
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    • v.33B no.2
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    • pp.118-130
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    • 1996
  • Fuzzy inference is very useful in expressing ambiguous problems quantitatively and solving them. But like the most of the knowledge based inference systems. It has many difficulties in constructing rules and no learning capability is available. In this paper, we proposed a fuzzy inference system based on fuzy associative memory to solve such problems. The inference system proposed in this paper is mainly composed of learning phase and inference phase. In the learning phase, the system initializes it's basic structure by determining fuzzy membership functions, and constructs fuzzy rules in the form of weights using learning function of fuzzy associative memory. In the inference phase, the system conducts actual inference using the constructed fuzzy rules. We applied the fuzzy inference system proposed in this paper to a pattern classification problem and show the results in the experiment.

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Development of Fuzzy Inference Systems for Protection to Electrical Accidents of Laboratory (연구실 전기사고방지를 위한 퍼지 추론 시스템 개발)

  • Park, Keon-Jun;Lee, Dong-Yoon
    • Journal of the Korea Academia-Industrial cooperation Society
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    • v.12 no.8
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    • pp.3636-3643
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    • 2011
  • To prevent the electrical accidents in the laboratory, we identify problems for periodic inspections of the electric field and develop a fuzzy inference system that can be practically applied to check items. Focusing on electrical safety in the lab environment, we draw check items that can be applied in common and develop a standard checklist that is consistent with the laboratory electrical safety and the periodic inspections. Using the standard checklist we select the items that may contain a linguistic ambiguity and define the membership functions for these items. We also have a safety rating defined by the membership function. Using these fuzzy variables we form the fuzzy rules in the form of 'If-Then' and develop a fuzzy inference system through the fuzzy engine. From this, electrical accidents could be prevented in advance continuously by managing the intelligent and efficient inspection and electrical safety to prevent the electrical accidents in the laboratory.

Integrity Assessment Models for Bridge Structures Using Fuzzy Decision-Making (퍼지의사결정을 이용한 교량 구조물의 건전성평가 모델)

  • 안영기;김성칠
    • Journal of the Korea Concrete Institute
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    • v.14 no.6
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    • pp.1022-1031
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    • 2002
  • This paper presents efficient models for bridge structures using CART-ANFIS (classification and regression tree-adaptive neuro fuzzy inference system). A fuzzy decision tree partitions the input space of a data set into mutually exclusive regions, each region is assigned a label, a value, or an action to characterize its data points. Fuzzy decision trees used for classification problems are often called fuzzy classification trees, and each terminal node contains a label that indicates the predicted class of a given feature vector. In the same vein, decision trees used for regression problems are often called fuzzy regression trees, and the terminal node labels may be constants or equations that specify the predicted output value of a given input vector. Note that CART can select relevant inputs and do tree partitioning of the input space, while ANFIS refines the regression and makes it continuous and smooth everywhere. Thus it can be seen that CART and ANFIS are complementary and their combination constitutes a solid approach to fuzzy modeling.