Search results for "Fuzzy Logic."

Expression of cell cycle markers and human papillomavirus infection in oral squamous cell carcinoma: use of fuzzy neural networks.

2005

Our aim was to evaluate in oral squamous cell carcinoma (OSCC) the relationship between some cell cycle markers and HPV infection, conditionally to age, gender and certain habits of patients, and to assess the ability of fuzzy neural networks (FNNs) in building up an adequate predictive model based on logic inference rules. Eighteen cases of OSCC were examined by immunohistochemistry for MIB-1, PCNA and survivin expression; presence of HPV DNA was investigated in exfoliated oral mucosa cells by nested PCR (nPCR, MY09-MY11/GP5-GP6), and HPV genotype was determined by direct DNA sequencing. Data were analyzed by traditional statistics (TS) and FNNs. HPV DNA was found in 9/18 OSCCs (50.0 %) wi…

A Fuzzy Chance-constraint Programming Model for a Home Health Care Routing Problem with Fuzzy Demand

2017

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.

Pricing Policies of Excess Capacity in Make to Order Production Systems

2014

The research concerns a make to order manufacturing environment and two classes of customers who submit orders. The core customers have a contract with the firm at fixed services level (price and due date). The short-term customers submit the orders based on the price set by the firm. In this paper, it is proposed a pricing policy based on fuzzy logic to set the price for the short-term customers. The fuzzy approach captures the state of the manufacturing systems in terms of congestion in order to set the price. The policy proposed is compared to a fixed price, and to a state-dependent policy based on three levels of price. A discrete event simulation environment is used to test the propose…

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…

On the importance of perspective and flexibility for efficiency measurement: effects on the ranking of decision-making units

2017

[EN] The efficiency of a firm can be assessed from several perspectives and using a variety of methodologies. Data envelopment analysis (DEA) is one of the most commonly used methodologies. Conventional DEA analyses or models allow one to classify decision-making units (DMUs) into efficient and inefficient ones based on their efficiency scores, which could also be used for ranking DMUs; however, such rankings generally show many ties. Super-efficiency DEA analyses have been proposed to address the tie issue. On the other hand, conventional DEA analyses only take account of a single perspective in estimating efficiency scores. Cross-efficiency DEA analyses provide an alternative that takes a…

Optimal design of tube hydroforming processes: A fuzzy-logic-based approach

2004

In recent years, tube hydroforming has become an economic and industrially suitable alternative to various traditional stamping processes, in particular for small batch production. In the present paper, an artificial intelligence system based on fuzzy logic was implemented for tube hydroforming process design. The aim was to achieve a process design procedure able to prevent forming defects and guarantee the achievement of the desired final shape of the component. In particular, the process design concerns the internal pressure history and the axial feeding. The fuzzy system is able to provide optimal trajectories for both the controlled parameters, producing a defect-free final part.

Probabilistic Fuzzy Approach to Evaluation of Logistics Service Effectiveness

2014

Received: 9 September 2014 Abstract Accepted: 11 October 2014 Logistics service providers offer a whole or partial logistics business service over a certain time period. Between such companies, the effectiveness of specific logistics services can vary. Logistics service providers seek the effective performance of logistics service. The purpose of this paper is to present a new approach for the evaluation of logistics service effectiveness, along with a specific computer system implementing the proposed approach – a sophisticated inference system, an extension of the Mamdani probabilistic fuzzy system. The paper presents specific knowledge concerning the relationships between effectiveness i…

Fuzzy selecting local region level set algorithm

2015

In this work, we introduced a novel localized region based level set model which is simultaneously effective for heterogeneous object or/and background and robust against noise. As such, we propose to minimize an energy functional based on a selective local average, i.e., when computing the local average, instead to use the intensity of all the pixels surrounding a given pixel, we first give a local Gaussian fuzzy membership to be a background or an object pixel to each of these surrounding pixels and then, we use the fuzzy weighted local average of these pixels to replace the traditional local average. With the graphics processing units' acceleration, the local lattice Boltzmann method is …