Document Type : Research Paper
Authors
1 Mechanical Engineering Department, Amirkabir University of Technology (Tehran Polytechnic).
2 Department of Statistics, Faculty of Basic Science, University of Kurdistan, Sanandaj.
Abstract
Traditional TSK system employs standard membership functions with adjustable crisp parameters in the IF part and linear combinations of input variables in the THEN part, which leads to loss of data fuzziness. Moreover, linear THEN part of this system restricts the number of learning parameters. On the other hand, parameters of the system are tuned to meet a predefined error threshold, but the system does not necessarily display actual structure of data, which impairs its interpretability. This work proposes modifications to the TSK system to tackle these issues and improve its performance. Extended TSK System (ETSK) is presented by replacing crisp parameters of membership functions with fuzzy numbers and adopting arbitrary functions in THEN part of the system. In addition, a Clustering-based TSK system (CTSK) is proposed, which is established from fuzzy clustering algorithms and represents structures and patterns of the data. CTSK has no IF part parameters to tune, which makes the system much faster, but its THEN part is the same as ETSK. Finally, CETSK system is presented as a combination of CTSK and ETSK to study the possibility of further improvements of the systems. The IF parts of TSK, ETSK, and CETSK are tuned by genetic algorithms and their THEN parts are adjusted by the least-squares estimate method. Performance of the systems are studied using 22 datasets in terms of accuracy and runtime. On average, CTSK is 10.82% and 4.84% more accurate than TSK and CETSK; and 91.58% and 92.21% faster than these systems, respectively. CETSK is 6.27% more accurate than TSK, but 6.91% slower because fuzzy clustering and genetic algorithms are jointly employed to tune its IF part whereas only genetic algorithms is used in TSK for this purpose.
Keywords: Fuzzy systems, fuzzy clustering, genetic algorithms, gradient descent algorithm, particle swarm optimization, least-squares estimate method, TSK system, fuzzy numbers.
Keywords
- Fuzzy systems
- fuzzy clustering
- genetic algorithms
- gradient descent algorithm
- particle swarm optimization
- least-squares estimate method
- TSK system
- fuzzy numbers
Main Subjects
(2025), 87-101. https://doi.org/10.22111/ijfs.2025.51386.9078
Aspects, 30 (2017), 1391-1400. https://doi.org/10.5829/idosi.ije.2017.30.09c.12
outliers: Review and development, Expert Systems with Applications, 165 (2021), 113856. https://doi.org/10.
1016/j.eswa.2020.113856
10.1007/s41066-020-00230-6
Expert Systems with Applications, 42 (2015), 2121-2135. https://doi.org/10.1016/j.eswa.2014.09.036
series using linear combinations of independent variables, Applied Soft Computing, 35 (2015), 151-160. https:
//doi.org/10.1016/j.asoc.2015.06.028
gas consumptions using genetic fuzzy systems, Energy, 83 (2015), 252-266. https://doi.org/10.1016/j.energy.
2015.02.020
for clustering noisy data, Applied Soft Computing, 53 (2017), 262-283. https://doi.org/10.1016/j.asoc.2016.
12.049
https://doi.org/10.1016/j.asoc.2020.106332
clustering noisy data and its convergence proof, Neurocomputing, 219 (2017), 186-202. https://doi.org/10.1016/
j.neucom.2016.09.025
(2011), 62-82. https://doi.org/10.1016/j.fss.2011.05.003
imbalanced data, Information Fusion, 98 (2023), 101845. https://doi.org/10.1016/j.inffus.2023.101845
in Electrical and Computer Engineering, 17 (2017), 3-10. https://doi.org/10.4316/AECE.2017.04001
fuzzy knowledge bases, Advances in Fuzzy Systems–Applications and Theory, World Scientific, 19 (2001). https:
//doi.org/10.1142/4177
and adaptive control of nonlinear systems, Applied Soft Computing, 137 (2023), 110161. https://doi.org/10.
1016/j.asoc.2023.110161
Information Sciences, 582 (2022), 243-257. https://doi.org/10.1016/j.ins.2021.09.015
in genetic fuzzy rule-based classification systems: Accuracy-complexity trade-off, Knowledge-Based Systems,
54 (2013), 32-41. https://doi.org/10.1016/j.knosys.2013.07.011
learning method, Neurocomputing, 473 (2022), 54-67. https://doi.org/10.1016/j.neucom.2021.12.011
on Systems, Man, and Cybernetics, 34 (2004), 1478-1489. https://doi.org/10.1109/TSMCB.2004.825938
Information Science and Technology, 26 (2023), 351-364. https://doi.org/10.59277/ROMJIST.2023.3-4.08
fuzzy model, Information Sciences, 652 (2024), 119740. https://doi.org/10.1016/j.ins.2023.119740
systems for medical diagnosis, Scientific African, 20 (2023), e01610. https://doi.org/10.1016/j.sciaf.
2023.e01610
fuzzy based inverter for power quality improvement in grid-tied PV systems, Measurement: Sensors, 25 (2023),
100638. https://doi.org/10.1016/j.measen.2022.100638
Journal of Systems Science, 55 (2024), 771-813. https://doi.org/10.1080/00207721.2023.2293486
learning algorithm of TSK fuzzy classifier, Applied Soft Computing, 127 (2022), 109410. https://doi.org/10.
1016/j.asoc.2022.109410
fuzzy numbers based on the concept of magnitude, Iranian Journal of Fuzzy Systems, 20 (2023), 137-153. https:
//doi.org/10.22111/ijfs.2023.43939.7738
Computing, 151 (2024), 111151. https://doi.org/10.1016/j.asoc.2023.111151
//doi.org/10.1016/j.fss.2021.07.009
56-78. https://doi.org/10.1016/j.fss.2022.03.001
//doi.org/10.1016/0165-0114(88)90113-3
1 (1993), 1-24. https://doi.org/10.1109/TFUZZ.1993.390281
on Systems, Man, and Cybernetics, SMC-15, (1985), 116-132. https://doi.org/10.1109/TSMC.1985.
6313399
10 (2010), 481-489. https://doi.org/10.1016/j.asoc.2009.08.034
Transactions on Fuzzy Systems, 15 (2007), 1145-1161. https://doi.org/10.1109/TFUZZ.2007.896325
Knowledge-Based Systems, 241 (2022), 108203. https://doi.org/10.1016/j.knosys.2022.108203
and its application on color image segmentation, Expert Systems with Applications, 241 (2024), 122270. https:
//doi.org/10.1016/j.eswa.2023.122270
Knowledge-Based Systems, 263 (2023), 110292. https://doi.org/10.1016/j.knosys.2023.110292
classification, Information Fusion, 92 (2023), 350-362. https://doi.org/10.1016/j.inffus.2022.12.014
fuzzy system fusion: A survey at hierarchical, wide and stacked levels, Information Fusion, 101 (2024), 101977.
https://doi.org/10.1016/j.inffus.2023.101977