Search results for "Fuzzy"
showing 10 items of 747 documents
Fixed point theory for cyclic weak ϕ-contraction in fuzzy metric spaces
2012
In this paper, we introduce cyclic weak $\phi-$contractions in fuzzy metric spaces and utilize the same to prove some results on existence and uniqueness of fixed point in fuzzy metric spaces. Some related results are also proved besides furnishing illustrative examples.
Set-valued mappings in partially ordered fuzzy metric spaces
2014
Abstract In this paper, we provide coincidence point and fixed point theorems satisfying an implicit relation, which extends and generalizes the result of Gregori and Sapena, for set-valued mappings in complete partially ordered fuzzy metric spaces. Also we prove a fixed point theorem for set-valued mappings on complete partially ordered fuzzy metric spaces which generalizes results of Mihet and Tirado. MSC:54E40, 54E35, 54H25.
Modello fuzzy di calcolo della distanza di visibilità per il sorpasso su strade extraurbane ad unica carreggiata bidirezionale
2002
Lo studio di modelli teorici che ben rappresentino, nella loro articolazione, le manovre di guida in sede stradale è da sempre un esercizio tanto praticato quanto complesso. La difficoltà di delineare compiutamente tali manovre, di definirne l’interazione cinematica dei veicoli coinvolti è comprovata dalla varietà di modelli presenti in letteratura. Con il presente lavoro ci si propone di pervenire alla formulazione di un modello originale di calcolo della distanza di visibilità per il sorpasso su strade bidirezionali ad unica carreggiata, il quale tenga debitamente conto del coacervo delle variabili cinematiche, meccaniche, geometriche, ambientali e di traffico, così come del comportamento…
On Fuzzy Stochastic Integral Equations—A Martingale Problem Approach
2011
In the paper we consider fuzzy stochastic integral equations using the methods of stochastic inclusions. The idea is to consider an associated martingale problem and its solutions in order to obtain a solution to the fuzzy stochastic equation.
Optimal Control Under Fuzzy Conditions for Dynamical Systems Associated with the Second Order Linear Differential Equations
2020
This paper is devoted to an optimal trajectory planning problem with uncertainty in location conditions considered as a problem of constrained optimal control for dynamical systems. Fuzzy numbers are used to incorporate uncertainty of constraints into the classical setting of the problem under consideration. The proposed approach applied to dynamical systems associated with the second order linear differential equations allows to find an optimal control law at each \(\alpha \)-level using spline-based methods developed in the framework of the theory of splines in convex sets. The solution technique is illustrated by numerical examples.
The fall and the fragmentation of national clusters: Cluster evolution in the paper and pulp industry
2012
Abstract A common expectation in evolutionary cluster studies is that national clusters engage in competitive interactions that lead to a continuous stream of changes in global dominance. Our fuzzy-set analysis on the evolution of the paper and pulp industry demonstrates that globalization has dramatically changed this situation. National clusters have largely faded away; the value chain dominance is now held by technology suppliers who are global hubs in majority of identifiable business activities in the focal industry. Our results imply that when industrial decline is accentuated by industrial concentration in some part of the value chain the national clusters may lose their importance.
Survival causal patterns of social and commercial entrepreneurial initiatives in Spain
2021
This research aims at analysing the influence of a holistic configuration of factors related to industry and the characteristics of the entrepreneur and the business, on the survival of social and commercial entrepreneurial initiatives in both, new and consolidated companies. The sample ranges from 2,851 to 2,109 firms, according to the period considered, and has been obtained from the reports of the projects submitted to the Assistance Programme to Young Entrepreneurs, promoted by the Valencian Institute of Youth. Other sources of information have been the Institute’s own reports and the Chambers of Commerce. A configurational analysis is performed using the Fuzzy-Set Qualitative Comparati…
Revisiting bank failure in the United States: a fuzzy-set analysis
2020
Past financial crises have illustrated the importance of recognising the combinations of factors that can cause financial distress in the banking industry. Accordingly, this study uses fuzzy-set qualitative comparative analysis (fsQCA) to identify the combinations of factors that lead to bank failure. The data consist of 30 annual financial ratio series for 156 U.S. banks over a 15-year period (2001–2015). Identifying combinations of conditions that can produce bank failure is crucial to help regulators and bank managers. The fsQCA presented in this paper sheds light on the relationships between combinations of conditions and bank failure, providing a solution comprising two sufficient and …
Prioritization of students’ needs for education service design and development by embedding AHP and fuzzy set theory: A case study
2015
Student satisfaction represents a strategic factor for many universities towards increasing competition concerning students recruitment. Thus, nowadays many universities take into account typical customer-oriented industry’s approaches for the education service design and development. In such a condition, prioritization of students’ needs represents a crucial step to appropriately adopt these approaches. This paper proposes an effective way to evaluate importance of students’ needs based on the Analytic Hierarchy Process (AHP) method, in which linguistic variables are parameterized by means of triangular fuzzy numbers, to deal with uncertainty, subjectivity and vagueness. Finally, a case st…
Speed control design for a vehicle system using fuzzy logic and PID controller
2015
This paper consists of designing fuzzy and PID controllers for controlling the vehicle speed. The dynamic of the system is modeled to provide a transfer function for the plant. Fuzzy and PID controller are designed for linear model. The external disturbances such road grade is considered to stabilizing the system. Both controllers are modeled using MATLAB Simulink software. Finally, a comparative assessment of each simulated result is done based on the response characteristics.