• Title/Summary/Keyword: fuzzy subsets

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Fuzzy linguistic control of arc welding process (퍼지 논리 제어기를 이용한 아크용접 공정제어)

  • 부광석;양완행;조형석
    • 제어로봇시스템학회:학술대회논문집
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    • 1990.10a
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    • pp.356-361
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    • 1990
  • This paper presents a new self organizing fuzzy linguistic control (SOFLC) strategy for application to an arc welding process control. The proposed SOFLC is based on on-line modification of the control rules according to the extent of deviation of the one step ahead predictive output of the process from the desired output. The Predictive output of the process is estimated by a fuzzy predictor which is updated from the input and output data of the process. The rule base of the fuzzy subsets describing the control rules is modified by the improving mechanism based on the hill climbing approach. Simulation results show that this proposed SOFLC improves the response of the process in presence of the variation of the process dynamic characteristics.

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On a Novel Way of Processing Data that Uses Fuzzy Sets for Later Use in Rule-Based Regression and Pattern Classification

  • Mendel, Jerry M.
    • International Journal of Fuzzy Logic and Intelligent Systems
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    • v.14 no.1
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    • pp.1-7
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    • 2014
  • This paper presents a novel method for simultaneously and automatically choosing the nonlinear structures of regressors or discriminant functions, as well as the number of terms to include in a rule-based regression model or pattern classifier. Variables are first partitioned into subsets each of which has a linguistic term (called a causal condition) associated with it; fuzzy sets are used to model the terms. Candidate interconnections (causal combinations) of either a term or its complement are formed, where the connecting word is AND which is modeled using the minimum operation. The data establishes which of the candidate causal combinations survive. A novel theoretical result leads to an exponential speedup in establishing this.

A Fuzzy Continuous Petri Net Model for Helper T cell Differentiation

  • Park, In-Ho;Na, Do-Kyun;Lee, Kwang-H.;Lee, Do-Heon
    • Proceedings of the Korean Society for Bioinformatics Conference
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    • 2005.09a
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    • pp.344-347
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    • 2005
  • Helper T(Th) cells regulate immune response by producing various kinds of cytokines in response to antigen stimulation. The regulatory functions of Th cells are promoted by their differentiation into two distinct subsets, Th1 and Th2 cells. Th1 cells are involved in inducing cellular immune response by activating cytotoxic T cells. Th2 cells trigger B cells to produce antibodies, protective proteins used by the immune system to identify and neutralize foreign substances. Because cellular and humoral immune responses have quite different roles in protecting the host from foreign substances, Th cell differentiation is a crucial event in the immune response. The destiny of a naive Th cell is mainly controlled by cytokines such as IL-4, IL-12, and IFN-${\gamma}$. To understand the mechanism of Th cell differentiation, many mathematical models have been proposed. One of the most difficult problems in mathematical modeling is to find appropriate kinetic parameters needed to complete a model. However, it is relatively easy to get qualitative or linguistic knowledge of a model dynamics. To incorporate such knowledge into a model, we propose a novel approach, fuzzy continuous Petri nets extending traditional continuous Petri net by adding new types of places and transitions called fuzzy places and fuzzy transitions. This extension makes it possible to perform fuzzy inference with fuzzy places and fuzzy transitions acting as kinetic parameters and fuzzy inference systems between input and output places, respectively.

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INTUITIONISTIC FUZZY IDEALS IN ORDERED SEMIGROUPS

  • Khan, Asghar;Khan, Madad;Hussain, Saqib
    • Journal of applied mathematics & informatics
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    • v.28 no.1_2
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    • pp.311-324
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    • 2010
  • We prove that a regular ordered semigroup S is left simple if and only if every intuitionistic fuzzy left ideal of S is a constant function. We also show that an ordered semigroup S is left (resp. right) regular if and only if for every intuitionistic fuzzy left(resp. right) ideal A = <$\mu_A$, $\gamma_A$> of S we have $\mu_A(a)\;=\;\mu_A(a^2)$, $\gamma_A(a)\;=\;\gamma_A(a^2)$ for every $a\;{\in}\;S$. Further, we characterize some semilattices of ordered semigroups in terms of intuitionistic fuzzy left(resp. right) ideals. In this respect, we prove that an ordered semigroup S is a semilattice of left (resp. right) simple semigroups if and only if for every intuitionistic fuzzy left (resp. right) ideal A = <$\mu_A$, $\gamma_A$> of S we have $\mu_A(a)\;=\;\mu_A(a^2)$, $\gamma_A(a)\;=\;\gamma_A(a^2)$ and $\mu_A(ab)\;=\;\mu_A(ba)$, $\gamma_A(ab)\;=\;\gamma_A(ba)$ for all a, $b\;{\in}\;S$.

FUZZY SUBRINGS OF FUNDAMENTAL RINGS

  • Davvaz, B.
    • The Pure and Applied Mathematics
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    • v.11 no.2
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    • pp.127-132
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    • 2004
  • $H_v$-rings first were introduced by Vougiouklis in 1990. The largest class of algebraic systems satisfying ring-like axioms is the $H_v$-ring. Let R be an $H_v$-ring and ${\gamma}_R$ the smallest equivalence relation on R such that the quotient $R/{\gamma}_R$, the set of all equivalence classes, is a ring. In this case $R/{\gamma}_R$ is called the fundamental ring. In this short communication, we study the fundamental rings with respect to the product of two fuzzy subsets.

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A Design and Implementation of the Intelligent Diagnosis System for Diseases associated with Acute Abdominal Pain Based on Fuzzy Relational Products (퍼지관계곱 기반 급성복통과 관련된 지능형 질환 진단시스템의 설계 및 구현)

  • Hyun, Woo-Seok
    • The KIPS Transactions:PartB
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    • v.10B no.2
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    • pp.197-204
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    • 2003
  • Because most conventional systems of medical diagnosis focus on small subsets of classes of diseases of particular human organs, it is difficult to diagnosis when dealing with symptoms are related to many diseases. The author proposes an intelligent diagnosis system for diseases associated with acute abdominal pain based on fuzzy relational products (IDS-DAAP) to implement conventional system (DS-DAAP). Compared with DS-DAAP, new approach with IDS-DAAP shows that the system proposed here improves diagnosis rate and reduces diagnosis time.

Fuzzy Decision Making-based Recommendation Channel System using the Social Network Database (소셜 네트워크 데이터베이스를 이용한 퍼지 결정 기반의 추천 채널 시스템)

  • Ma, Linh Van;Park, Sanghyun;Jang, Jong-hyun;Park, Jaehyung;Kim, Jinsul
    • Journal of Digital Contents Society
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    • v.17 no.5
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    • pp.307-316
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    • 2016
  • A user usually gets the same suggesting results as everyone else in most of the multimedia social services, nowadays. To address the challenging problem of personalization in the social network, we propose a method which exploits user's activities, user's moods, and user's friend relationships from the social network to build a decision-making system. Depending on a current state of the user's mood, this system infers the most appropriated video for the user. In the system, the user evaluates a set of the given recommendation methods which extract from the user's database social network and assigns a vague value to each method by a weight. Then, we find the fuzzy collection solution for the system and classify the set of methods into subsets, and order the subsets based on its local dominance to choose the best appropriate method. Finally, we conduct an experiment using the YouTube API with a lot of video types. The experiment result shows that the channel recommendation system appropriately affords the user's character, it is more satisfying than the current YouTube based on an evaluation of several users.

Ordinary Smooth Topological Spaces

  • Lim, Pyung-Ki;Ryoo, Byeong-Guk;Hur, Kul
    • International Journal of Fuzzy Logic and Intelligent Systems
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    • v.12 no.1
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    • pp.66-76
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    • 2012
  • In this paper, we introduce the concept of ordinary smooth topology on a set X by considering the gradation of openness of ordinary subsets of X. And we obtain the result [Corollary 2.13] : An ordinary smooth topology is fully determined its decomposition in classical topologies. Also we introduce the notion of ordinary smooth [resp. strong and weak] continuity and study some its properties. Also we introduce the concepts of a base and a subbase in an ordinary smooth topological space and study their properties. Finally, we investigate some properties of an ordinary smooth subspace.

The application of fuzzy spatial overlay method to the site selection using GSIS (GSIS를 이용한 입지선정에 있어 퍼지공간중첩기법의 적용에 관한 연구)

  • 임승현;조기성
    • Journal of the Korean Society of Surveying, Geodesy, Photogrammetry and Cartography
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    • v.17 no.2
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    • pp.177-187
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    • 1999
  • Up to date, in many application fields of GSIS, we usually have used vector-based spatial overlay or grid-based spatial algebra for extraction and analysis of spatial data. But, because these methods are based on traditional crisp set, concept which is used these methods. shows that many kinds of spatial data are partitioned with sharp boundary. That is not agree with spatial distribution pattern of data in the real world. Therefore, it has a error that a region or object is restricted within only one attribution (One-Entity-one-value). In this study, for improving previous methods that deal with spatial data based on crisp set, we are suggested to apply into spatial overlay process the concept of fuzzy set which is good for expressing the boundary vagueness or ambiguity of spatial data. two methods be given. First method is a fuzzy interval partition by fuzzy subsets in case of spatially continuous data, and second method is fuzzy boundary set applied on categorical data. with a case study to get a land suitability map for the development site selection of new town, we compared results between Boolean analysis method and fuzzy spatial overlay method. And as a result, we could find out that suitability map using fuzzy spatial overlay method provide more reasonable information about development site of new town, and is more adequate type in the aspect of presentation.

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Generation of Efficient Fuzzy Classification Rules Using Evolutionary Algorithm with Data Partition Evaluation (데이터 분할 평가 진화알고리즘을 이용한 효율적인 퍼지 분류규칙의 생성)

  • Ryu, Joung-Woo;Kim, Sung-Eun;Kim, Myung-Won
    • Journal of the Korean Institute of Intelligent Systems
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    • v.18 no.1
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    • pp.32-40
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    • 2008
  • Fuzzy rules are very useful and efficient to describe classification rules especially when the attribute values are continuous and fuzzy in nature. However, it is generally difficult to determine membership functions for generating efficient fuzzy classification rules. In this paper, we propose a method of automatic generation of efficient fuzzy classification rules using evolutionary algorithm. In our method we generate a set of initial membership functions for evolutionary algorithm by supervised clustering the training data set and we evolve the set of initial membership functions in order to generate fuzzy classification rules taking into consideration both classification accuracy and rule comprehensibility. To reduce time to evaluate an individual we also propose an evolutionary algorithm with data partition evaluation in which the training data set is partitioned into a number of subsets and individuals are evaluated using a randomly selected subset of data at a time instead of the whole training data set. We experimented our algorithm with the UCI learning data sets, the experiment results showed that our method was more efficient at average compared with the existing algorithms. For the evolutionary algorithm with data partition evaluation, we experimented with our method over the intrusion detection data of KDD'99 Cup, and confirmed that evaluation time was reduced by about 70%. Compared with the KDD'99 Cup winner, the accuracy was increased by 1.54% while the cost was reduced by 20.8%.