Search results for "fuzzy"

Fuzzy approach based model of interrelated factors for financial industry client risk assessment

2020

Application of Graded Fuzzy Preconcept Lattices in Risk Analysis

2021

Assessing supply chain risks in the automotive industry through a modified MCDM-based FMECA

2020

Supply chains are complex networks that receive assiduous attention in the literature. Like any complex network, a supply chain is subject to a wide variety of risks that can result in significant economic losses and negative impacts in terms of image and prestige for companies. In circumstances of aggressive competition among companies, effective management of supply chain risks (SCRs) is crucial, and is currently a very active field of research. Failure Mode, Effects and Criticality Analysis (FMECA) has been recently extended to SCR identification and prioritization, aiming at reducing potential losses caused by lack of risk control. This article has a twofold objective. First, SCR assess…

Risk analysis using fuzzy set theory of accidental exposure of medical staff during brachytherapy procedures

2010

Using fuzzy set theory, this paper presents results from risk analyses that explore potential exposure of medical operators working in a high dose rate brachytherapy irradiation plant. In these analyses, the HEART methodology, a first generation method for human reliability analysis, has been employed to evaluate the probability of human error. This technique has been modified on the basis of fuzzy set concepts to take into account, more directly, the uncertainties of the so-called error-promoting factors on which the method is based. Moreover, with regard to some identified accident scenarios, fuzzy potential dose was also evaluated to estimate the relevant risk. The results also provide s…

Fuzzy Metric Approach to Aggregation of Risk Levels

2019

In this paper we propose a special construction of a general aggregation operator. The construction allows to aggregate fuzzy sets taking into account the distance between elements of the universe. We consider the case when fuzzy sets to be aggregated represent the risk level evaluation by several experts. We describe how the proposed construction could be applied for risk level assessment in the case when a strong fuzzy metric is used to characterize the similarity of objects under evaluation.

Fuzzy cognitive maps for knowledge-oriented human risk management in industry

2021

This contribution proposes an integrated approach making use of Fuzzy Cognitive Maps (FCMs) to organise in a flexibleway human knowledge about decision-making (DM) problems of interest in industry. By modelling human reasoning, FCMs allow to represent real phenomena on the basis of spontaneous human brainstorming on relations between pairs of relevant DM elements. Because of its characteristics, the use of FCMs can be effective to model DM problems such as human risk management, particularly critical in the industrial business sector. After identifying human risks in the existing literature, FCMs will be used to define relations among risks, which will be later prioritised by means of a mod…

Modeling risk perception in ATIS context through Fuzzy Logic

2011

Abstract This research is aimed at investigating the effect of accuracy of ATIS (Advanced Traveller Information Systems) in terms of route choices and travellers concordance to informative system. A Stated Preference Experiment has been made by using a Travel Simulator developed at the Technische Universiteit of Delft (The Netherlands). During the experiment respondents have been asked to make repeated route choices in presence of ATIS. Two kinds of information have been tested: descriptive (respondents are provided with the estimated travel times on each route), and prescriptive (respondents are provided with the estimated shortest route). For each kind of information four levels of accura…

On the robust design of unknown inputs Takagi-Sugeno observer

2012

This paper deals with the observer design for Takagi-Sugeno (T-S) fuzzy models subject to unknown inputs and disturbance affecting both states and outputs of the system. Sufficient conditions to design an unknown input T-S observer are given in Linear Matrix Inequalities (LMIs) terms. Relaxations are introduced by using intermediate variables. Numerical example is given to illustrate the effectiveness of the given result.

Parallel Genetic Algorithms for the Tuning of a Fuzzy AQM Controller

2003

This paper presents the results of the application of a parallel Genetic Algorithm (GA) in order to design a Fuzzy Proportional Integral (FPI) controller for active queue management on Internet routers. The Active Queue Management (AQM) policies are those policies of router queue management that allow the detection of network congestion, the notification of such occurrences to the hosts on the network borders, and the adoption of a suitable control policy. Two different parallel implementations of the genetic algorithm are adopted to determine an optimal configuration of the FPI controller parameters. Finally, the results of several experiments carried out on a forty nodes cluster of workst…

Intelligent Traction Control for Wheeled Space Vehicles

2006

This paper presents the SC-MER, safety control for Mars exploration rover, an innovative traction control scheme for wheeled mobile vehicles. The system is thought to be used on space mission rovers and is based on fuzzy logic and competitive neural networks to achieve optimal navigation on rough terrain with variable morphology. The main goal of this research is to minimize the power consumption needed during the navigation and improve the overall stability and safety of the rover itself