Search results for "fuzzy"
showing 10 items of 747 documents
Quantifying stenosis in renal arteriograms: a fuzzy syntactic analysis.
1999
AbstractThe introduction of fuzzy logic improves a system for the automatic quantification of renal artery lesions seen in digital subtraction angiograms. A two-step approach has been followed. An earlier system based on non-fuzzy syntactic analysis provided a clear symbolic description of the stenotic lesions. Although this system worked correctly, it did not take into account the variability and uncertainty inherent to image processing and to knowledge on the reference diameter. This system has been improved by the introduction of fuzzy logic in the representation of the reference diameter. It provides a description of the stenosis in terms of fuzzy quantities. To illustrate the benefits …
Longitudinal Study on Sustained Attention to Response Task (SART): Clustering Approach for Mobility and Cognitive Decline
2022
The Sustained Attention to Response Task (SART) is a computer-based go/no-go task to measure neurocognitive function in older adults. However, simplified average features of this complex dataset lead to loss of primary information and fail to express associations between test performance and clinically meaningful outcomes. Here, we combine a novel method to visualise individual trial (raw) information obtained from the SART test in a large population-based study of ageing in Ireland and an automatic clustering technique. We employed a thresholding method, based on the individual trial number of mistakes, to identify poorer SART performances and a fuzzy clusters algorithm to partition the da…
A fuzzy multi-criteria decision-making methodology to optimise olive agro-engineering processes based on geo-spatial technologies
2016
In southern Italy, the olive oil sector is an important part of the primary sector and its development requires support from research to ensure its sustainability. This work proposes the first step for set up a decision support system (DSS) for establishing mechanisation in agricultural operations for different olive groves. To contribute to this goal researches have been carried out to test the ability of remote sensing (RS) and geographic information system (GIS) to map olive groves and their agronomic characteristics. In detail, this study aimed to classify olives grove areas in terms of agronomic suitability and detect horticultural characteristics of olive groves in order to develop a …
Benchmarking of airports service quality by a new fuzzy MCDM approach
2015
Recent approaches to the service quality evaluation problem are focused on the employment of multi-criteria decisionmaking (MCDM) procedures, since processes related to service quality evaluation presentmeaningful communality elements to MCDM ones. Based on such assumption, in the present paper a new fuzzy MCDMapproach is developed tocomparatively evaluate passenger service quality of the international airports inSicily (Italy). In particular, by incorporating the respondents confidence level and degree of optimism on fuzzy assessments, quality scores of main airport service criteria are estimated, whereas ELECTRE multi criteria decision support methodis proposed to point out theservices qu…
Fixed point theorems for fuzzy mappings and applications to ordinary fuzzy differential equations
2014
Abstract Ran and Reurings (Proc. Am. Math. Soc. 132(5):1435-1443, 2004) proved an analog of the Banach contraction principle in metric spaces endowed with a partial order and discussed some applications to matrix equations. The main novelty in the paper of Ran and Reurings involved combining the ideas in the contraction principle with those in the monotone iterative technique. Motivated by this, we present some common fixed point results for a pair of fuzzy mappings satisfying an almost generalized contractive condition in partially ordered complete metric spaces. Also we give some examples and an application to illustrate our results. MSC:46S40, 47H10, 34A70, 54E50.
Bornological structures on many-valued sets
2017
Conditioning on MV-algebras and additive measures —I
1997
Abstract We present a lattice-ordered semigroup approach for the foundation of conditional events which covers the special situations where the underlying (unconditional) events are Boolean or fuzzy, respectively. Our proposal is quite different from other, ring theoretical, approaches. The problem of extending additivity of uncertainty measures from unconditional to conditional events will be discussed.
Upper and lower generalized factoraggregations based on fuzzy equivalence relation
2014
We develop the concept of a general factoraggre-gation operator introduced by the authors on the basis of an equivalence relation and applied in two recent papers for analysis of bilevel linear programming solving parameters. In the paper this concept is generalized by using a fuzzy equivalence relation instead of the crisp one. By using a left-continuous t-norm and its residuum we define and investigate two modifications of such generalized construction: upper and lower generalized factoraggregations. These generalized factoraggregations can be used for construction of extensional fuzzy sets.
Fuzzy Relational Mathematical Morphology: Erosion and Dilation
2020
In the recent years, the subject if fuzzy mathematical morphology entered the field of interest of many researchers. In our recent paper [23], we have developed the basis of the (unstructured) L-fuzzy relation mathematical morphology where L is a quantale. In this paper we extend it to the structured case. We introduce structured L-fuzzy relational erosion and dilation operators, study their basic properties, show that under some conditions these operators are dual and form an adjunction pair. Basing on the topological interpretation of these operators, we introduce the category of L-fuzzy relational morphological spaces and their continuous transformations.
On Extensional Fuzzy Sets Generated by Factoraggregation
2014
We develop the concept of a general factoraggregation operator introduced by the authors on the basis of an equivalence relation and applied in two recent papers for analysis of bilevel linear programming solving parameters. In the paper this concept is generalized by using a fuzzy equivalence relation instead of the crisp one. We show how the generalized factoraggregation can be used for construction of extensional fuzzy sets and consider approximations of arbitrary fuzzy sets by extensional ones.