• 제목/요약/키워드: If-Then rule

검색결과 214건 처리시간 0.03초

The Study on Inconsistent Rule Based Fuzzy Logic Control using Neural Network

  • Cho, Jae-Soo;Park, Dong-Jo;Z. Bien
    • 한국지능시스템학회:학술대회논문집
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    • 한국퍼지및지능시스템학회 1997년도 춘계학술대회 학술발표 논문집
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    • pp.145-150
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    • 1997
  • In this paper is studied a method of fuzzy logic control based on possibly inconsistent if-then rules representing uncertain knowledge or imprecise data. In most cases of practical applications adopting fuzzy if-then rule bases, inconsistent rules have been considered as ill-defined rules and, thus, not allowed to be in the same rule base. Note, however, that, in representing uncertain knowledge by using fuzzy if-then rules, the knowledge sometimes can not be represented in literally consistent if-then rules. In this regard, when it is hard to obtain consistent rule base, we propose the weighted rule base fuzzy logic control depending on output performance using neural network and we will derive the weight update algorithm. Computer simulations show the proposed method has good performance to deal with the inconsistent rule base fuzzy logic control. And we discuss the real application problems.

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음의 순수 연관성 규칙 평가 기준의 제안 (Proposition of negatively pure association rule threshold)

  • 박희창
    • Journal of the Korean Data and Information Science Society
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    • 제22권2호
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    • pp.179-188
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    • 2011
  • 연관성 규칙은 방대한 데이터베이스에서 항목간의 관계를 명확히 수치화 함으로써 그들간의 관련성을 표시해주는 기법으로 데이터 마이닝 기법들 중에서 가장 많이 활용되고 있다. 어느 항목이 발생하면 다른 항목도 발생한다는 규칙을 발견하기 위한 기법이 연관성 규칙이라면 음의 연관성 규칙 마이닝은 어느 항목이 발생하면 다른 항목도 발생하지 않는다는 규칙을 찾아내는 기법이다. 기존의 연관성 규칙에 음의 연관성 규칙을 추가하게 되면 어떤 제품을 판매하기 위해서는 그 제품만 마케팅 하는 것 뿐 만 아니라 더 나아가 그 제품이 아닌 어느 제품을 마케팅 하는 것이 필요한지를 판단할 수 있다. 본 논문에서는 음의 연관성 규칙의 단점을 보완할 수 있는 음의 순수 연관성 규칙의 측도들을 제시하고 흥미도 측도가 가져야 할 조건들을 조사하였으며, 예제 데이터를 활용하여 음의 순수 연관성 규칙의 유용성에 대해 살펴보았다.

Effective Design of Inference Rule for Shape Classification

  • Kim, Yoon-Ho;Lee, Sang-Sock;Lee, Joo-Shin
    • 한국지능시스템학회:학술대회논문집
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    • 한국퍼지및지능시스템학회 1998년도 The Third Asian Fuzzy Systems Symposium
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    • pp.417-422
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    • 1998
  • This paper presents a method of object classification from dynamic image based on fuzzy inference algorithm which is suitable for low speed such as, conveyor, uninhabited transportation. At first, by using feature parameters of moving object, fuzzy if - then rule that can be able to adapt the wide variety of surroundings is developed. Secondly, implication function for fuzzy inference are compared with respect the proposed algorithm. Simulation results are presented to testify the performance and applicability of the proposed system.

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음의 연관성 규칙 생성을 위한 음의 기여 순수 신뢰도의 제안 (Negatively attributable and pure confidence for generation of negative association rules)

  • 박희창
    • Journal of the Korean Data and Information Science Society
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    • 제23권5호
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    • pp.939-948
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    • 2012
  • 데이터 마이닝 기법들 중에서 가장 많이 활용되고 있는 연관성 규칙은 방대한 데이터베이스에서 항목간의 관계를 흥미도 측도에 의해 명확히 수치화함으로써 그들간의 관련성을 표시해주는 기법이다. 양의 연관성 규칙 마이닝이 임의의 한 항목이 발생하면 다른 항목도 발생한다는 규칙을 생성하기 위한 기법인 반면에, 음의 연관성 규칙은 어느 항목이 발생하면 다른 항목은 발생하지 않는다는 규칙을 찾아내는 기법이다. 음의 연관성 규칙은 양의 연관성 규칙의 활용과 마찬가지로 고객의 구매 경향 및 마케팅 정책을 제시할 수 있고 교차판매와 매장 진열 등과 같이 타겟 마케팅에 활용 가능하다. 양의 연관성 규칙에 음의 연관성 규칙을 추가하게 되면 어떤 제품을 판매하기 위해서는 그 제품만 마케팅 하는 것뿐만 아니라 더 나아가 그 제품이 아닌 어느 제품을 마케팅 하는것이 필요한지를 판단할 수 있다. 본 논문에서는 기존의 음의 신뢰도의 단점을 보완할 수 있는 음의 기여 순수 신뢰도를 제안한 후, 이에 대해 흥미도 측도가 가져야 할 조건들을 조사하였으며, 예제 데이터를 활용하여 음의 기여 순수 신뢰도의 유용성을 고찰하였다.

An improvement of LEM2 algorithm

  • The, Anh-Pham;Lee, Young-Koo;Lee, Sung-Young
    • 한국정보과학회:학술대회논문집
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    • 한국정보과학회 2011년도 한국컴퓨터종합학술대회논문집 Vol.38 No.1(A)
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    • pp.302-304
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    • 2011
  • Rule based machine learning techniques are very important in our real world now. We can list out some important application which we can apply rule based machine learning algorithm such as medical data mining, business transaction mining. The different between rules based machine learning and model based machine learning is that model based machine learning out put some models, which often are very difficult to understand by expert or human. But rule based techniques output are the rule sets which is in IF THEN format. For example IF blood pressure=90 and kidney problem=yes then take this drug. By this way, medical doctor can easy modify and update some usable rule. This is the scenario in medical decision support system. Currently, Rough set is one of the most famous theory which can be used for produce the rule. LEM2 is the algorithm use this theory and can produce the small set of rule on the database. In this paper, we present an improvement of LEM2 algorithm which incorporates the variable precision techniques.

퍼지-뉴럴 네트워크를 이용한 심전도 패턴 분류시스템 설계 (Design of ECG Pattern Classification System Using Fuzzy-Neural Network)

  • 김민수;이승로;서희돈
    • 대한전자공학회:학술대회논문집
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    • 대한전자공학회 2002년도 하계종합학술대회 논문집(5)
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    • pp.273-276
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    • 2002
  • This paper has design of ECG pattern classification system using decision of fuzzy IF-THEN rules and neural network. each fuzzy IF-THEN rule in our classification system has antecedent lingustic values and a single consequent class. we use a fuzzy reasoning method based on a single winner rule in the classification phase. this paper in, the MIT/BIH arrhythmia database for the source of input signal is used in order to evaluate the performance of the proposed system. From the simulation results, we can effectively pattern classification by application of learned from neural networks.

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퍼지 ID3를 이용한 지속가능경영의 패턴분석에 관한 연구 (A Study on Pattern Analysis of Sustainability Management Using Fuzzy ID3)

  • 김홍진;황승국
    • 한국지능시스템학회논문지
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    • 제18권5호
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    • pp.700-705
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    • 2008
  • 본 논문에서는 중소기업의 지속가능경영을 평가하기 위한 평가모델을 제안하였다. 또한, 퍼지 ID3에 의하여 구해진 패턴분석에 대한 if-then 룰과 의사결정트리를 보여준다. 본 논문에서 제안한 평가모델은 중소기업의 경쟁력 향상의 평가도구로서 사용이 가능하다. 중소기업이 퍼지 ID3를 이용한 지속가능경영의 패턴분석에 사용된 평가 룰을 사전에 알 수 있다면 중소기업들의 자체 평가에 효과적으로 사용될 수 있으리라 기대된다.

ERROR BOUNDS OF TRAPEZOIDAL RULE ON SUBINTERVALS USING DISTRIBUTION

  • Hong, Bum-Il;Hahm, Nahm-Woo
    • 호남수학학술지
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    • 제29권2호
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    • pp.245-257
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    • 2007
  • We showed in [2] that if $r\leq2$, then the average error between simple Trapezoidal rule and the composite Trapezoidal rule on two consecutive subintervals is proportional to $h^{2r+3}$ using zero mean Gaussian distribution under the assumption that we have subintervals (for simplicity equal length) partitioning and that each subinterval has the length. In this paper, if $r\geq3$, we show that zero mean Gaussian distribution of average error between simple Trapezoidal rule and the composite Trapezoidal rule on two consecutive subintervals is bounded by $Ch^8$.

Hardware Approach to Fuzzy Inference―ASIC and RISC―

  • Watanabe, Hiroyuki
    • 한국지능시스템학회:학술대회논문집
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    • 한국퍼지및지능시스템학회 1993년도 Fifth International Fuzzy Systems Association World Congress 93
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    • pp.975-976
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    • 1993
  • This talk presents the overview of the author's research and development activities on fuzzy inference hardware. We involved it with two distinct approaches. The first approach is to use application specific integrated circuits (ASIC) technology. The fuzzy inference method is directly implemented in silicon. The second approach, which is in its preliminary stage, is to use more conventional microprocessor architecture. Here, we use a quantitative technique used by designer of reduced instruction set computer (RISC) to modify an architecture of a microprocessor. In the ASIC approach, we implemented the most widely used fuzzy inference mechanism directly on silicon. The mechanism is beaded on a max-min compositional rule of inference, and Mandami's method of fuzzy implication. The two VLSI fuzzy inference chips are designed, fabricated, and fully tested. Both used a full-custom CMOS technology. The second and more claborate chip was designed at the University of North Carolina(U C) in cooperation with MCNC. Both VLSI chips had muliple datapaths for rule digital fuzzy inference chips had multiple datapaths for rule evaluation, and they executed multiple fuzzy if-then rules in parallel. The AT & T chip is the first digital fuzzy inference chip in the world. It ran with a 20 MHz clock cycle and achieved an approximately 80.000 Fuzzy Logical inferences Per Second (FLIPS). It stored and executed 16 fuzzy if-then rules. Since it was designed as a proof of concept prototype chip, it had minimal amount of peripheral logic for system integration. UNC/MCNC chip consists of 688,131 transistors of which 476,160 are used for RAM memory. It ran with a 10 MHz clock cycle. The chip has a 3-staged pipeline and initiates a computation of new inference every 64 cycle. This chip achieved an approximately 160,000 FLIPS. The new architecture have the following important improvements from the AT & T chip: Programmable rule set memory (RAM). On-chip fuzzification operation by a table lookup method. On-chip defuzzification operation by a centroid method. Reconfigurable architecture for processing two rule formats. RAM/datapath redundancy for higher yield It can store and execute 51 if-then rule of the following format: IF A and B and C and D Then Do E, and Then Do F. With this format, the chip takes four inputs and produces two outputs. By software reconfiguration, it can store and execute 102 if-then rules of the following simpler format using the same datapath: IF A and B Then Do E. With this format the chip takes two inputs and produces one outputs. We have built two VME-bus board systems based on this chip for Oak Ridge National Laboratory (ORNL). The board is now installed in a robot at ORNL. Researchers uses this board for experiment in autonomous robot navigation. The Fuzzy Logic system board places the Fuzzy chip into a VMEbus environment. High level C language functions hide the operational details of the board from the applications programme . The programmer treats rule memories and fuzzification function memories as local structures passed as parameters to the C functions. ASIC fuzzy inference hardware is extremely fast, but they are limited in generality. Many aspects of the design are limited or fixed. We have proposed to designing a are limited or fixed. We have proposed to designing a fuzzy information processor as an application specific processor using a quantitative approach. The quantitative approach was developed by RISC designers. In effect, we are interested in evaluating the effectiveness of a specialized RISC processor for fuzzy information processing. As the first step, we measured the possible speed-up of a fuzzy inference program based on if-then rules by an introduction of specialized instructions, i.e., min and max instructions. The minimum and maximum operations are heavily used in fuzzy logic applications as fuzzy intersection and union. We performed measurements using a MIPS R3000 as a base micropro essor. The initial result is encouraging. We can achieve as high as a 2.5 increase in inference speed if the R3000 had min and max instructions. Also, they are useful for speeding up other fuzzy operations such as bounded product and bounded sum. The embedded processor's main task is to control some device or process. It usually runs a single or a embedded processer to create an embedded processor for fuzzy control is very effective. Table I shows the measured speed of the inference by a MIPS R3000 microprocessor, a fictitious MIPS R3000 microprocessor with min and max instructions, and a UNC/MCNC ASIC fuzzy inference chip. The software that used on microprocessors is a simulator of the ASIC chip. The first row is the computation time in seconds of 6000 inferences using 51 rules where each fuzzy set is represented by an array of 64 elements. The second row is the time required to perform a single inference. The last row is the fuzzy logical inferences per second (FLIPS) measured for ach device. There is a large gap in run time between the ASIC and software approaches even if we resort to a specialized fuzzy microprocessor. As for design time and cost, these two approaches represent two extremes. An ASIC approach is extremely expensive. It is, therefore, an important research topic to design a specialized computing architecture for fuzzy applications that falls between these two extremes both in run time and design time/cost. TABLEI INFERENCE TIME BY 51 RULES {{{{Time }}{{MIPS R3000 }}{{ASIC }}{{Regular }}{{With min/mix }}{{6000 inference 1 inference FLIPS }}{{125s 20.8ms 48 }}{{49s 8.2ms 122 }}{{0.0038s 6.4㎲ 156,250 }} }}

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판정궤환이 있는 복소 LMS 퍼지 적응 등화기 (Complex LMS Fuzzy Adaptive Equalizer with Decision Feedback)

  • 이상연;김재범;이기용;이충웅
    • 한국통신학회논문지
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    • 제21권10호
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    • pp.2579-2585
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    • 1996
  • In this paper, a complex fuzzy adaptive decision feedback equalizer(CFADFE) based on the LMS algorithm is proposed. The propoed equalizer is based on the complex fuzzy adaptive equalizer. The CFADFE isconstructed from a set of changeable complex fuzzy IF-THEN rules, where the 'IF' part of the rule is characterized by the state from a set of changealble complex fuzzy IF-THEN rules, where the 'IF' part of the rule is characterized by the state of the desision feedback. the role of decision feedback is to reduce the computational complexity. Computer simulation of the decision feedback. The role of decision feedback is to reduce the computational complexity. Computer simulation shosw that the CFADFE notonly reduces the computational complexity but also improves the performance compared with the conventional complex fuzzy adaptive equalizers. We also show that the adaptation speed is greatly improved by incorporating some linguistic information about the channel into the equalzer. It is applied to M-ary QAM digital communication system with linear and nonlinear complex channel characteristics.

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