Interval type-2 fuzzy logic systems: theory and design

dc.contributorPh.D. Program in Electrical and Electronic Engineering.
dc.contributor.advisorKaynak, Okyay,
dc.contributor.authorKayacan, Erdal.
dc.date.accessioned2023-03-16T10:25:04Z
dc.date.available2023-03-16T10:25:04Z
dc.date.issued2011.
dc.description.abstractThis Ph.D. dissertation has four main objectives. Firstly, the noise reduction property of type-2 fuzzy logic systems that use a novel type-2 fuzzy membership function is studied. A number of papers exist in literature that claim the performance of type-2 fuzzy logic systems is better than that of type-1 fuzzy logic systems under noisy conditions, and this claim is supported by simulation studies only for some specific systems. In this dissertation, a simpler type-2 fuzzy logic system is considered with the novel membership function proposed in which the effect of input noise in the rule base is shown numerically in a general way. Secondly, fuzzy c-means clustering algorithm is proposed for type-2 fuzzy logic systems to determine the initial places of the membership functions to ensure that the gradient descent algorithm used afterwards converges in a shorter time. Thirdly, Levenberg-Marquardt algorithm is proposed for type-2 fuzzy neural networks. While conventional gradient descent algorithms use only the first order derivative, the proposed algorithm used in this dissertation benefits from the first and the second-order derivatives which makes the training procedure faster. Finally, a novel sliding mode control theory-based learning algorithm is proposed to train the parameters of the type-2 fuzzy neural networks. In the approach, instead of trying to minimize an error function, the weights of the network are tuned by the proposed algorithm in a way that the error is enforced to satisfy a stable equation. The parameter update rules are derived for both Gaussian and triangular type-2 fuzzy membership functions, and the convergence of the weights is proven by Lyapunov stability method. The simulation results indicate that the type-2 fuzzy structure with the proposed learning algorithm results in a better performance than its type-1 fuzzy counterpart.
dc.format.extent30cm.
dc.format.pagesxix, 130 leaves ;
dc.identifier.otherEE 2011 K381 PhD
dc.identifier.urihttps://digitalarchive.library.bogazici.edu.tr/handle/123456789/13102
dc.publisherThesis (Ph.D.)-Bogazici University. Institute for Graduate Studies in Science and Engineering, 2011.
dc.relationIncludes appendices.
dc.relationIncludes appendices.
dc.subject.lcshFuzzy systems.
dc.subject.lcshFuzzy logic.
dc.subject.lcshLogic design -- Computer programs.
dc.titleInterval type-2 fuzzy logic systems: theory and design

Files

Original bundle
Now showing 1 - 1 of 1
Loading...
Thumbnail Image
Name:
b1660319.012369.001.PDF
Size:
4.07 MB
Format:
Adobe Portable Document Format

Collections