Search results for "fuzzy"
showing 10 items of 747 documents
A fuzzy ServQual based method for reliable measurements of education quality in Italian higher education area
2013
In recent years, the attention that the European Community has focused on the education sector has produced a new university commitment addressed to quality aspects for all education related services. In fact, a quality oriented service requires excellence in the design and planning of service activities, as well as during its delivering and also for the adopted service performance evaluation method. However, considering that service performance evaluations are deeply based on stakeholders' judgments, they can be characterized by possible uncertainties related to incompleteness for partial ignorance, imprecision for subjectivity and even vagueness. Therefore, under these conditions, unrelia…
A fuzzy methodology to alleviate information overload in elearning
2013
Some aspects of eLearning experience can be en- hanced in a very natural way by using the basic tools offered by fuzzy logic. As a matter of exam- ple, consider the uncontrolled growth of informa- tion produced in a collaborative-oriented context, in which each participant (e.g. students, teachers) is able to insert and share new contents (e.g. com- ments, texts) concerning a university course. All the incrementally added pieces of information can be evaluated in several ways: by the intervention of a “dictator” (e.g. the teacher), using a rating form, or even according to the frequency of access. As contents rapidly become unusable for the effects of information overload, basic tools of fu…
A fuzzy framework to evaluate service quality in the healthcare industry: An empirical case of public hospital service evaluation in Sicily
2016
A novel fuzzy framework is considered to analyze healthcare service quality.The fundamental quality structure of healthcare service delivered in Sicily is described.The public healthcare in Sicily (Italy) is strategically analyzed.Strategic stakeholders' oriented implications for healthcare improvements are given. A novel fuzzy evaluation framework is applied in this study to evaluate service quality in the public healthcare sector. In particular, the proposed framework is based on the ServQual disconfirmation paradigm and incorporates the Analytic Hierarchy Process (AHP) method to elicit reliable estimations of service quality expectations. Moreover, degrees of uncertainty, subjectivity an…
A sizing approach for stand-alone hybrid photovoltaic-wind-battery systems: A Sicilian case study
2018
Abstract Solar and wind energy are the two most available renewable energy resources in the world. In this paper, a high-resolution analysis that allows sizing a hybrid photovoltaic-wind turbine-battery banks has been carried out. The analysis aims to minimize the annualized cost of the systems satisfying two reliability constraints. The solution has been obtained numerically by means of an iterative technique. The decision variables are the photovoltaic area, wind turbine radius, and battery capacity. A high-resolution model, based on fuzzy logic inference system, has been developed to evaluate the number of active occupants and the domestic electricity consumption. In order to allow a mor…
Fuzzifying topology induced by a strong fuzzy metric
2016
A construction of a fuzzifying topology induced by a strong fuzzy metric is presented. Properties of this fuzzifying topology, in particular, its convergence structure are studied. Our special interest is in the study of the relations between products of fuzzy metrics and the products of the induced fuzzifying topologies.
Ideal-valued topological structures
2010
With L a complete lattice and M a continuous lattice, this paper demonstrates an adjunction between M -valued L-topological spaces (i.e. (L,M )-topological spaces) and Idl(M )-valued L-topological spaces where Idl(M ) is the complete lattice of all ideals of M . It is shown that the right adjoint functor provides a procedure of generating (L,M )-topologies from antitone families of (L,M )-topologies. This procedure is then applied to give an internal characterization of joins in the complete lattice of all (L,M )-topologies on a given set.
Probabilistic and fuzzy logic in clinical diagnosis
2007
In this study I have compared classic and fuzzy logic and their usefulness in clinical diagnosis. The theory of probability is often considered a device to protect the classical two-valued logic from the evidence of its inadequacy to understand and show the complexity of world [1]. This can be true, but it is not possible to discard the theory of probability. I will argue that the problems and the application fields of the theory of probability are very different from those of fuzzy logic. After the introduction on the theoretical bases of fuzzy approach to logic, I have reported some diagnostic argumentations employing fuzzy logic. The state of normality and the state of disease often figh…
A construction of a fuzzy topology from a strong fuzzy metric
2016
<p>After the inception of the concept of a fuzzy metric by I. Kramosil and J. Michalek, and especially after its revision by A. George and G. Veeramani, the attention of many researches was attracted to the topology induced by a fuzzy metric. In most of the works devoted to this subject the resulting topology is an ordinary, that is a crisp one. Recently some researchers showed interest in the fuzzy-type topologies induced by fuzzy metrics. In particular, in the paper (J.J. Mi\~{n}ana, A. \v{S}ostak, {\it Fuzzifying topology induced by a strong fuzzy metric}, Fuzzy Sets and Systems, 6938 DOI information: 10.1016/j.fss.2015.11.005.) a fuzzifying topology ${\mathcal T}:2^X \to [0,1]$ …
Finite-Time Hâ Filtering for T-S Fuzzy Discrete-Time Systems with Time-Varying Delay and Norm-Bounded Uncertainties
2015
In this paper, we investigate the filtering problem of discrete-time Takagi–Sugeno (T–S) fuzzy uncertain systems subject to time-varying delays. A reduced-order filter is designed. With the augmentation technique, a filtering error system with delayed states is obtained. In order to deal with time delays in system states, the filtering error system is first transformed into two interconnected subsystems. By using a two-term approximation for the time-varying delay, sufficient delay-dependent conditions of finite-time boundedness and $H_{\infty }$ performance of the filtering error system are derived with the Lyapunov function. Based on these conditions, the filter design methods are propose…
Neural Petri Control: an application on a mobile robot
2006
In the present work, an innovative nonlinear controller of nonholonomic mechanical systems, characterized by a dynamic not well known model a priori, using a new neural model obtained by the combination of a Petri net with a neural network, is proposed. The performances of the control algorithm are evaluated for tasks of tracking of time trajectories. The study of the stability of the total system to closed loop is based on the Lyapunov theory. Simulation experiments, made taking into consideration a nonholonomic mobile robot, to two wheels, allowed to verify the theoretical results.