This paper investigates a fuzzy multi-objective vendor selection program under lean procurement based on cost minimization, delivery schedule violation minimization, and maximizing the quality level of the purchased quantity. Specifically, the paper incorporates the vendor production capacity uncertainty into the model to identify an appropriate selection policy for vendors under practical oper...

We propose a robust method for estimating the time-varying spectrum of a non-stationary random process. Our approach extends Thomson's powerful multiple window spectrum estimation scheme to the time-frequency and timescale planes. The method reenes previous extensions of Thomson's method through optimally concentrated window and wavelet functions and a statistical test for extracting chirping l...

window analysis is a known technique to evaluate performance during the time periods based on data envelopment analysis. in application of window analysis is assumed that efficient frontier have not changed during the periods in the study. unlike the window analysis, malmquist index tries to identify difference between efficient frontiers and separated them. but the means of different frontier ...

This survey paper shows different mechanisms for controlling congestion in ATM network and some suggested solution for the existing mechanism to be modified using fuzzy logic. Different mechanisms are Jump Window (JW), Exponentially Weighted Moving Average (EWMA), and traditional Leaky Bucket (LB) and Fuzzy Leaky Bucket Algorithm. The Fuzzy Leaky Bucket (FLB) modifies the token rate according t...

The competitive vehicle routing problem is one of the important issues in transportation area. In this paper a new method for competitive VRP with time windows and stochastic demand is introduced. In the presented method a three time bounds are given and the probability of arrival time between each time bound is assumed to be uniform. The demands of each customer are different in each time wind...

Image enhancement is an important stage in the image-processing domain. The most known image enhancement method is the histogram equalization. This method is an automated one, and realizes a simultaneous modification for brightness and contrast in the case of monochrome images and for brightness, contrast, saturation and hue in the case of color images. Simple and efficient methods can be obtai...

Network management and control is a complex problem that requires intelligent, control methodologies to obtain satisfactory performance. Round trip time (RTT) scaling mechanism has been introduced for changing congestion window and to perform congestion control satisfactorily in all circumstances. This paper presents a fuzzy RTT scaling (FRTTS) scheme that performs RTT scaling and RTT schedulin...

This study introduces a green location, routing and inventory problem with customer satisfaction, backup distribution centers and risk of routes in the form of a non-linear mixed integer programming model. In this regard, time window is considered to increase the customer satisfaction of the model and transportation risks is taken into account for the reliability of the system. In addition, dif...

Aimed at fuzzy clustering based on the generalized entropy, an image segmentation algorithm by joining space information of image is presented in this paper. For solving the optimization problem with generalized entropy’s fuzzy clustering, both Hopfield neural network and multi-synapse neural network are used in order to obtain cluster centers and fuzzy membership degrees. In addition, to impro...