E-service evaluation is a complex problem in which many qualitative attributes must be considered. These kinds of attributes make the evaluation process hard and vague. Cost–benefit analyses applied to various areas are usually based on the data under certainty or risk. In case of uncertain, vague, and/or linguistic data, the fuzzy set theory can be used to handle the analysis. In this article,...

A straightforward approach for designing fuzzy logic based controllers in Matlab/Simulink environment is presented in this paper. The approach focuses on the fuzzy rule base construction using the time varying values of control error (e) and its change (∆e) mapped on e-∆e space. In order to show the generalized model simplicity of the proposed approach, a fuzzy logic controller (FLC) is designe...

Countries need to be aware of the stage of their current e-Commerce maturity for choosing the right strategy to move forward. For this purpose, we develop a country-level decision support framework to determine maturation stage of e-Commerce in a country. At first, e-Commerce maturity scores of local e-Markets in each regional e-Market are calculated using a fuzzy bi-level Technique for Order P...

This paper introduces an evaluation methodologies for the e-learners’ behaviour that will be a feedback to the decision makers in e-learning system. Learner's profile plays a crucial role in the evaluation process to improve the e-learning process performance. The work focuses on the clustering of the e-learners based on their behaviour into specific categories that represent the learner's prof...

We show that analogously to classical probability theory the conditional expectation E ( ? ~ X ) of a fuzzy random variable Y w.r.t. a fuzzy random variable X is w.r.t. a suitable metric the best approximation o f ? by measurable functions ofX. Furthermore, several linear regression functions, i.e. best approximation of ? by linear functions o f z and examples for random LR-fuzzy numbers and Ga...

In this paper, the concept of a fuzzy graph structure is introduced based on the concept of graph structure given by E. Sampathkumar, in Bull. Kerala Math. Assoc., Vol 3, No.2 (2006 December), 65123. New concepts like ρi − edge, ρi − path, ρi − cycle, ρi − tree, ρi − forest, fuzzy ρi − cycle, fuzzy ρi − tree, fuzzy ρi − forest etc. are introduced. Some results are obtained. We continue the stud...

I n this paper, we review a new definition of fuzzy functional dependency based on conditional probability and i ts application to approximate data reduction related to operation of projection in classical relational database in order to construct fuzzy integrity constraints [l]. W e introduce the concept of partial fuzzy functional dependency which expresses the fact that a given attribute X d...

The notion of fuzzy function based on many-valued equivalence relations (many-valued similarity relations (equalities) [17, 18, 19], fuzzy equivalence relations [4, 6, 7, 21, 22, 26], similarity relations [1, 2, 3, 15, 28], indistinguishability operators [27], etc.) has been introduced by several authors, and applied to category theory [5], approximate reasoning and fuzzy control theory [8, 10,...

This article deals with the recognition of recurring multivariate time series patterns modelled sample-point-wise by parametric fuzzy sets. An efficient classification-based approach for the online recognition of incompleted developing patterns in streaming time series is being presented. Furthermore, means are introduced to enable users of the recognition system to restrict results to certain ...