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We will introduce and study different fuzzy-set oriented computational models of neurons. The generic topologies of the neurons emerging there are significantly influenced by basic logic operators(AND, OR, NOT) encountered in the theory of fuzzy sets. The logical flavor of the proposed constructs is expressed in terms of operators used in their formalization and a way of their superposition in the neurons. The two broad categories of neurons embrace basic aggregation neurons (named AND and OR neurons) and referential processing units (such as matching, dominance, inclusion neurons). The specific features of the neurons are flexibly modeled with the aid of triangular norms. The inhibitory and excitatory characteristics are captured by embodying direct and complemented (negated) input signals. We will propose various topologies of neural networks put together with the use of these neurons and demonstrate straightforward relationships coming off between the problem specificity and the resulting architecture of the network. This limpid way of mapping the domain knowledge onto the structure of the network contributes significantly toward enhancements in learning processes in the network and substantially facilitates its interpretation.< <ETX xmlns:mml="http://www.w3.org/1998/Math/MathML" xmlns:xlink="http://www.w3.org/1999/xlink">></ETX>
Nowadays fuzzy modeling is dominated by data-driven constructs.The resulting granular constructs (say, fuzzy rules) are developed on a basis of numeric data.The genuine challenge arises when the available data become very limited and/or noisy so that it becomes evident that the quality of the constructed model could be quite low.If some domain knowledge has been acquired in the past and becomes now available in the form of some fuzzy models, its prudent usage could be highly advantageous.In this study, we assume that such domain knowledge is captured in the form of some other rule-based topologies constructed on a basis of some previously available data sets (which however cannot be accessed explicitly).To emphasize the very nature of system modeling being guided by this form of the reconciliation mechanism, we refer to the resulting methodology as experience-consistent fuzzy system identification.By coming up with a certain augmentation of the optimized performance index, it is demonstrated that the domain knowledge captured by the individual rule-based models play a similar role as a regularization component typically encountered in system identification.Detailed algorithmic considerations embrace several design scenarios in which we apply the mechanism of experience consistency at the level of conditions and conclusions of the rules.We also show that a level of achieved experience-driven consistency can be quantified through fuzzy sets (fuzzy numbers) of the parameters of the local models standing in the conclusion parts of the rules this leading to the emergence of granular constructs of fuzzy modeling.
Fuzzy models are constructs relying heavily on a qualitative domain knowledge and diverse optimization techniques. What makes them different from other models is their inherent embedding in the context of nonnumeric set or fuzzy set-oriented information. One can also look at the development of the fuzzy models from the perspective of data mining-a prudent and user-oriented sifting of data, qualitative observations and calibration of commonsense rules in an attempt to establish meaningful and useful relationships between system's variables. Having accepted this point of view, we analyze various methods of fuzzy clustering and make them uniform enough so that they can constitute a viable design platform. Several fuzzy clustering methods (especially Fuzzy C-Means) have been already exploited in the context of fuzzy modelling. Our claim is that these methods need some conceptual shift that makes them possible to cope with a notion of "directionality" of any model, namely its ability to determine the values of the output variable(s) given the actual values of the inputs and state variables. This aspect of directionality along with the assumed specificity of modelling, is addressed in depth and leads to a series of detailed algorithms.
Transfer learning has emerged as a solution for the cases where little or no labeled data are available in the training process. It leverages the previously acquired knowledge (a source domain with a large amount of labeled data) to facilitate solving the current tasks (a target domain with little labeled data). Many transfer learning methods have been proposed, and especially fuzzy transfer learning method, which is based on fuzzy systems, has been developed because of its capability to deal with the uncertainty in transfer learning. However, there is one issue with fuzzy transfer learning that has not yet been resolved: the domain selection problem, which is heavily depended on the knowledge transfer method and the applied prediction model. In this work, we explore the domain selection problem in TakagiSugeno fuzzy model when multiple source domains are accessible, and define the similarity between the source and target domains to provide guidance for the domain selection. The experiments on synthetic datasets are designed to simulate the situations of multiple sources in transfer learning, and demonstrate the rationality of the proposed similarity in selecting the source domain for the target domain. Further, the real-world datasets are used to validate the proposed domain adaptation method, and verify its capability in solving practical situations.
Energy saving becomes a central issue in the design of wireless sensor networks routing algorithms. The objective of this study is to maximize the survival time of wireless sensor networks routing with a sink node by developing an efficient routing algorithm based on the elite hybrid metaheuristic optimization algorithm. The proposed algorithm comes as an original method that innovatively brings together the global search abilities of the particle swarm optimization algorithm, difference operator of differential algorithm and pheromones of ant-colony optimization algorithm in order to avoid local search and retain diversity of the population. As a result, the method quickly finds an optimal solution. A novel routing algorithm based on the proposed elite hybrid metaheuristic optimization algorithm is designed. Comprehensive simulation studies show that the proposed algorithm can increase maximum lifetime of wireless sensor networks by 38% in comparison with the results being produced with the state-of-the art algorithm routing algorithms based on other population-based optimization algorithms.
It is known that bisymmetry generalizes the simultaneous commutativity and associativity in the framework of the unit interval. In this work, we will completely characterize two classes of bisymmetric aggregation operators: one with a neutral element and the other with the vertical and horizontal sections of the idempotent elements being smooth on a finite chain, but not necessarily smooth and commutative. Thus, the previous results, based on the smoothness that is known as a very restrictive condition, are improved. For example, there is only one smooth Archimedean t-norm on a finite chain. In this paper, the discrete bisymmetric aggregation operators are explored without the limit of the smoothness. As a by-product, it is deduced that for smooth aggregation operators on a finite chain, the bisymmetry is equivalent to the commutativity and associativity, which improves the conclusion obtained by Mas et al. that associativity and bisymmetry are equivalent for commutative smooth aggregation operators on a finite chain.
Abstract Quantitative software engineering is aimed at designing models describing software processes and products. While being noticeably dominated by statistical regression models, this area also embraces advanced techniques of computational intelligence and knowledge-based engineering including rule-based models, fuzzy models, and neural networks. The rationale behind their usage in the setting of Software Engineering is threefold: (a) the underlying distributions of datasets may not adhere to general assumptions that are usually made in the setting of linear regression models: (b) it is beneficial to build interpretable models that in some sense are user-friendly; (c) the models should be advanced and computationally appealing so that they exhibit some nonlinear characteristics as well as are fully equipped with learning abilities. The proposed architecture comprises alogic-based skeleton (blueprint) and an array of generic perceptrons as being commonly encountered in neurocomputing. The hybrid nature...