Search results for "Fuzzy set"
showing 10 items of 197 documents
Fuzzy modelling of HEART methodology: application in safety analyses of accidental exposure in irradiation plants
2009
The present paper refers to the obtained results by using Fuzzy Fault Tree analyses of accidental scenarios which entail the potential exposure of operators working in irradiation industrial plants. For these analyses the HEART methodology, a first generation of the Human Reliability Analysis method, has been employed to evaluate the probability of human erroneous actions. This technique has been modified by us on the basis of fuzzy set concept to more directly take into account the uncertainties of the so called error-promoting factors, on which the method is grounded. The results allow also to provide some recommendations on procedures and safety equipments to reduce the radiological expo…
A fuzzy programming method for optimization of autonomous logistics objects
2013
Recently several studies have explored the realization of autonomous control in production and logistic operations. In doing so, it has been tried to transmit the merit of decision-making from central controllers with offline decisions to decentralized controllers with local and real-time decision makings. However, this mission has still some drawbacks in practice. Lack of global optimization is one of them, i.e., the lost chain between the autonomous decentralized decisions at operational level and the centralized mathematical optimization with offline manner at tactical and strategic levels. This distinction can be reasonably solved by considering fuzzy parameters in mathematical programm…
Project Selection by Constrained Fuzzy AHP
2004
The selection of a project among a set of possible alternatives is a difficult task decision makers have to face. Difficulties in selecting a project arise because of the different goals involved and because of the large number of attributes to consider. Our approach is based upon a fuzzy extension of the Analytic Hierarchy Process (AHP). This paper focuses on the constraints that have to be considered within fuzzy AHP in order to take in account all the available information. This study demonstrates that by considering all the information deriving from the constraints better results in terms of certainty and reliability can be achieved.
Service quality benchmarking via a novel approach based on fuzzy ELECTRE III and IPA: an empirical case involving the Italian public healthcare conte…
2017
A novel fuzzy-based approach which combines ELECTRE III along with the Importance-Performance Analysis (IPA) is proposed in the present work to comparatively evaluate the service quality in the public healthcare context. Specifically, ELECTRE III is firstly considered to compare the service performance of examined hospitals in a noncompensatory manner. Afterwards, IPA is employed to support the service quality management to point out improvement needs and their priorities. The proposed approach also incorporates features of the Fuzzy Set Theory so as to address the possible uncertainty, subjectivity and vagueness of involved experts in evaluating the service quality. The model is applied to…
Note on the ranking of fuzzy numbers: conditions for a total order relation
1988
It is well-known that the set of fuzzy numbers is not ordered. The author states the conditions which have to be satisfied so that the problem of ranking fuzzy numbers has a solution. In fact, the subset of fuzzy numbers, the elements of which are strictly defined and continuous,is endowed with a total order relation.
Asymmetric modeling of organizational innovation
2015
[EN] This study revisits the theory, data, and analysis in Hervas-Oliver and Sempere-Ripoll (2014) and applies fuzzyset qualitative comparative analysis (fs/QCA) to organizational innovation effects and the influence on them of technological innovations. The influence of technological innovations (product and process) on organizational innovation and its effects is an inconclusive debate. Using fuzzy set comparative qualitative analysis (fs/QCA) on Hervas-Oliver and Sempere-Ripoll’s (2014) 9,369 organizational innovators, the present study offers more complex and nuanced antecedent conditions relating to organizational innovation beyond Hervas-Oliver and Sempere-Ripoll (2014) analysis based…
γ‐Agregation operators and some aspects of generalized aggregation problem
2010
We explore questions related to the aggregation operators and aggregation of fuzzy sets. No preliminary knowledge of the aggregation operators theory and of the fuzzy sets theory are required, because all necessary information is given in Section 2. Later we introduce a new class of γ‐aggregation operators, which “ignore” arguments less than γ. Due to this property γ‐aggregation operators simplify the aggregation process and extend the area of possible applications. The second part of the paper is devoted to the generalized aggregation problem. We use the definition of generalized aggregation operator, introduced by A. Takaci in [7], and study the pointwise extension of a γ‐agop. First publ…
Cyclic Dynamic Evaluation of Logistics Services Stakeholders Based on System with OFN Model
2021
The challenge for enterprises and supply chains is to deliver successful logistics services in compliance with their aims. Logistics services are affected by many stakeholders. Recognizing their impact on the undertaken services is important for the planning and execution of a sufficiently rigorous stakeholder management process. The aim of the paper is to present a new approach to the analysis of stakeholders - cyclic dynamic evaluation, which could be used in service management, such as in logistics services. We present a novel fuzzy inference system based on the mathematical apparatus of Ordered Fuzzy Numbers (OFNs). The evaluation of stakeholders consists in assessing key factors as - f…
SZACOWANIE CZASU REALIZACJI PROJEKTU PRZY NIEPRECYZYJNYCH ZMIENNYCH
2017
Praca przedstawia istotę i znaczenie problemu szacowania czasu realizacji projektów w warunkach niepewności i ryzyka z zastosowaniem skierowanych liczb rozmytych. W pracy przedstawiono autorskie podejście do szacowania czasu realizacji projektów bazujące na rozmytym modelu niepewności czasów czynności projektowych ze skierowaniem. Zaprezentowana rozszerzona metoda ścieżki krytycznej jest nowym podejściem, które do tej pory nie było prezentowane w takim ujęciu w literaturze tematu. W celu weryfikacji poprawności prezentowanego podejścia przedstawiono przykład obliczeniowy ilustrujący dany problem. Przedstawiono zalety proponowanego podejścia. Podejście to może znaleźć zastosowania w praktyce…
Soft ditopological spaces
2015
We introduce the concept of a soft ditopological space as the "soft Generalization" of the concept of a ditopological space as it is defined in the papers by L.M. Brown and co-authors, see e.g. L. M. Brown, R. Ert?rk, ?. Dost, Ditopological texture spaces and fuzzy topology, I. Basic Concepts, Fuzzy Sets and Systems 147 (2) (2004), 171-199. Actually a soft ditopological space is a soft set with two independent structures on it - a soft topology and a soft co-topology. The first one is used to describe openness-type properties of a space while the second one deals with its closedness-type properties. We study basic properties of such spaces and accordingly defined continuous mappings between…