Title :
Interval type-2 fuzzy logic systems: theory and design
Author :
Liang, Qilian ; Mendel, Jerry M.
Author_Institution :
Dept. of Electr. Eng. Syst., Univ. of Southern California, Los Angeles, CA, USA
fDate :
10/1/2000 12:00:00 AM
Abstract :
We present the theory and design of interval type-2 fuzzy logic systems (FLSs). We propose an efficient and simplified method to compute the input and antecedent operations for interval type-2 FLSs: one that is based on a general inference formula for them. We introduce the concept of upper and lower membership functions (MFs) and illustrate our efficient inference method for the case of Gaussian primary MFs. We also propose a method for designing an interval type-2 FLS in which we tune its parameters. Finally, we design type-2 FLSs to perform time-series forecasting when a nonstationary time-series is corrupted by additive noise where SNR is uncertain and demonstrate an improved performance over type-1 FLSs
Keywords :
forecasting theory; fuzzy logic; fuzzy set theory; fuzzy systems; inference mechanisms; time series; forecasting; fuzzy logic systems; fuzzy set theory; inference; membership functions; time-series; Additive noise; Control systems; Design methodology; Engines; Fuzzy logic; Fuzzy sets; Signal processing; Signal to noise ratio; Training data; Uncertainty;
Journal_Title :
Fuzzy Systems, IEEE Transactions on
