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Fuzzy Systems, IEEE Transactions on

Issue 1 • Date Feb 1999

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Displaying Results 1 - 10 of 10
  • Functional dependencies with null values, fuzzy values, and crisp values

    Publication Year: 1999 , Page(s): 97 - 103
    Cited by:  Papers (16)
    Save to Project icon | Request Permissions | Click to expandAbstract | PDF file iconPDF (292 KB)  

    Based on the concepts of the semantic proximity, we present a definition of the fuzzy functional dependency, We show that the inference rules for fuzzy functional dependencies, which are the same as Armstrong's axioms for the crisp case, are correct and complete. We also show that dependent constraints with dull values constitute a lattice. Functional dependencies in classical relational databases... View full abstract»

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  • Choquet fuzzy integral-based hierarchical networks for decision analysis

    Publication Year: 1999 , Page(s): 63 - 71
    Cited by:  Papers (40)
    Save to Project icon | Request Permissions | Click to expandAbstract | PDF file iconPDF (248 KB)  

    A Choquet fuzzy integral-based approach to hierarchical network implementation is investigated. In this approach, we generalized the fuzzy integral as an excellent component for decision analysis. The generalization involves replacing the max (or min) operator in information aggregation with a fuzzy integral-based neuron, resulting in increased flexibility. The characteristics of the Choquet fuzzy... View full abstract»

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  • An improved stable adaptive fuzzy control method

    Publication Year: 1999 , Page(s): 27 - 40
    Cited by:  Papers (93)
    Save to Project icon | Request Permissions | Click to expandAbstract | PDF file iconPDF (512 KB)  

    Stable adaptive fuzzy control is a self-tuning concept for fuzzy controllers that uses a Lyapunov-based learning algorithm, thus guaranteeing stability of the system plant-controller-learning algorithm and convergence of the plant output to a given reference signal. In the paper, two new methods for stable adaptive fuzzy control are presented. The first method is an extension of an existing concep... View full abstract»

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  • A characterization of the ordered weighted averaging functions based on the ordered bisymmetry property

    Publication Year: 1999 , Page(s): 93 - 96
    Cited by:  Papers (3)
    Save to Project icon | Request Permissions | Click to expandAbstract | PDF file iconPDF (184 KB)  

    This paper deals with the characterization of a class of aggregation operators. This class concerns operators that are symmetric, increasing, stable for the same positive linear transformations, and present a property close to the bisymmetry property: the ordered bisymmetry property. It is proved that the class investigated contains exactly the ordered weighted averaging operators introduced by Ya... View full abstract»

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  • Fuzzy control design for the trajectory tracking on uncertain nonlinear systems

    Publication Year: 1999 , Page(s): 53 - 62
    Cited by:  Papers (36)
    Save to Project icon | Request Permissions | Click to expandAbstract | PDF file iconPDF (476 KB)  

    Based on the concept of sliding-mode control (SMC), the paper designs fuzzy logic controls to achieve the prespecified trajectory tracking for an uncertain nonlinear system. The prespecified trajectory is composed of several nonisoclinal segments in the phase plane and is regarded as the piecewise sliding surface. First, let the uncertain system be approximated by a linguistic fuzzy rule base, the... View full abstract»

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  • Application of simulated annealing fuzzy model tuning to umbilical cord acid-base interpretation

    Publication Year: 1999 , Page(s): 72 - 84
    Cited by:  Papers (26)
    Save to Project icon | Request Permissions | Click to expandAbstract | PDF file iconPDF (360 KB)  

    Fuzzy logic and fuzzy set theory provide an important framework for representing and managing imprecision and uncertainty in medical expert systems, but the need remains to optimize such systems to enhance performance. The paper presents a general technique for optimizing fuzzy models in fuzzy expert systems (FESs) by simulated annealing (SA) and N-dimensional hill climbing simplex method. The app... View full abstract»

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  • Fuzzy control of queueing systems with heterogeneous servers

    Publication Year: 1999 , Page(s): 17 - 26
    Cited by:  Papers (19)
    Save to Project icon | Request Permissions | Click to expandAbstract | PDF file iconPDF (276 KB)  

    We consider the problem of optimal control of queueing systems with heterogeneous servers in parallel. The system objective is to assign customers dynamically to idle servers based on the state of the system so as to minimize the average cost of holding customers. Three cases, either known in the literature or new, are studied in detail: queueing systems with server heterogeneity in-service rates,... View full abstract»

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  • A robust self-tuning scheme for PI- and PD-type fuzzy controllers

    Publication Year: 1999 , Page(s): 2 - 16
    Cited by:  Papers (124)
    Save to Project icon | Request Permissions | Click to expandAbstract | PDF file iconPDF (492 KB)  

    Proposes a simple but robust model independent self-tuning scheme for fuzzy logic controllers (FLCs). Here, the output scaling factor (SF) is adjusted online by fuzzy rules according to the current trend of the controlled process. The rule-base for tuning the output SF is defined on error (e) and change of error (Δe) of the controlled variable using the most natural and unbiased membership f... View full abstract»

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  • A supervisory fuzzy neural network control system for tracking periodic inputs

    Publication Year: 1999 , Page(s): 41 - 52
    Cited by:  Papers (103)
    Save to Project icon | Request Permissions | Click to expandAbstract | PDF file iconPDF (372 KB)  

    A supervisory fuzzy neural network (FNN) control system is designed to track periodic reference inputs in this study. The control system is composed of a permanent magnet (PM) synchronous servo motor drive with a supervisory FNN position controller. The supervisory FNN controller comprises a supervisory controller, which is designed to stabilize the system states around a defined bound region and ... View full abstract»

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  • Consequences of the digitization on the performance of a fuzzy logic controller

    Publication Year: 1999 , Page(s): 85 - 92
    Cited by:  Papers (6)
    Save to Project icon | Request Permissions | Click to expandAbstract | PDF file iconPDF (192 KB)  

    The consequences of the finite wordlength on the performance of a digital fuzzy logic controller (FLC) based on Mamdani's inference algorithm are investigated. Digital implementations of FLCs involve three main types of errors due to the finiteness of the wordlength: analog-to-digital errors, membership function errors, and arithmetic errors. First, a statistical evaluation of the consequences of ... View full abstract»

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Aims & Scope

The IEEE Transactions on Fuzzy Systems (TFS) is published quarterly. TFS will consider papers that deal with the theory, design or an application of fuzzy systems ranging from hardware to software.

Full Aims & Scope

Meet Our Editors

Editor-in-Chief
Chin-Teng Lin
National Chiao-Tung University