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Development of a Simulation-Based Intelligent Decision Support System for the Adaptive Real-Time Control of Flexible Manufacturing Systems

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Journal of Software Engineering and Applications 2010年第7期3卷 661-673页

作者： Babak Shirazi iraj mahdavi Maghsud Solimanpur 不详

This paper describes a simulation-based intelligent decision support system (IDSS) for real time control of a flexible manufacturing system (FMS) with machine and tool flexibility. The manufacturing processes involved in FMS are complicated since each operation may be done by several machining centers. The system design approach is built around the theory of dynamic supervisory control based on a rule-based expert system. The paper considers flexibility in operation assignment and scheduling of multi-purpose machining centers which have different tools with their own efficiency. The architecture of the proposed controller consists of a simulator module coordinated with an IDSS via a real time event handler for implementing inter-process synchronization. The controller’s performance is validated by benchmark test problem.

关键词： Intelligent Decision Support System Real Time Control Flexible Manufacturing System Multi-Purpose Machining Centers

The Capacitated Location-Allocation Problem in the Presence of <i>k</i>Connections

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Applied Mathematics 2011年第8期2卷 947-952页

作者： Saber Shiripour Mehdi Amiri-Aref iraj mahdavi 不详

We consider a capacitated location-allocation problem in the presence of k connections on the horizontal line barrier. The objective is to locate a set of new facilities among a set of existing facilities and to allocate an optimal number of existing facilities to each new facility in order to satisfy their demands such that the summation of the weighted rectilinear barrier distances from new facilities to existing facilities is minimized. The proposed problem is designed as a mixed-integer nonlinear programming model. To show the efficiency of the model, a numerical example is provided. It is worth noting that the global optimal solution is obtained.

关键词： Capacitated Location-Allocation Problem Line Barrier Mixed Integer Nonlinear Programming

Fuzzy Least-Squares Linear Regression Approach to Ascertain Stochastic Demand in the Vehicle Routing Problem

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Applied Mathematics 2011年第1期2卷 64-73页

作者： Fatemeh Torfi Reza Zanjirani Farahani iraj mahdavi 不详

Estimation of stochastic demand in physical distribution in general and efficient transport routs management in particular is emerging as a crucial factor in urban planning domain. It is particularly important in some municipalities such as Tehran where a sound demand management calls for a realistic analysis of the routing system. The methodology involved critically investigating a fuzzy least-squares linear regression approach (FLLRs) to estimate the stochastic demands in the vehicle routing problem (VRP) bearing in mind the customer's preferences order. A FLLR method is proposed in solving the VRP with stochastic demands: approximate-distance fuzzy least-squares (ADFL) estimator ADFL estimator is applied to original data taken from a case study. The SSR values of the ADFL estimator and real demand are obtained and then compared to SSR values of the nominal demand and real demand. Empirical results showed that the proposed method can be viable in solving problems under circumstances of having vague and imprecise performance ratings. The results further proved that application of the ADFL was realistic and efficient estimator to face the sto- chastic demand challenges in vehicle routing system management and solve relevant problems.

关键词： Fuzzy Least-Squares Stochastic Location Routing Problems

A Novel Approach for Finding a Shortest Path in a Mixed Fuzzy Network

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Wireless Sensor Network 2010年第2期2卷 148-160页

作者： Ali Tajdin iraj mahdavi Nezam mahdavi-Amiri Bahram Sadeghpour-Gildeh Reza Hassanzadeh 不详

We present a novel approach for computing a shortest path in a mixed fuzzy network, network having various fuzzy arc lengths. First, we develop a new technique for the addition of various fuzzy numbers in a path using -cuts. Then, we present a dynamic programming method for finding a shortest path in the network. For this, we apply a recently proposed distance function for comparison of fuzzy numbers. Four examples are worked out to illustrate the applicability of the proposed approach as compared to two other methods in the literature as well as demonstrate the novel feature offered by our algorithm to find a fuzzy shortest path in mixed fuzzy networks with various settings for the fuzzy arc lengths.

关键词： Fuzzy Numbers -Cut Shortest Path Dynamic Programming

Heuristic Approaches for Cell Formation in Cellular Manufacturing

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Journal of Software Engineering and Applications 2010年第7期3卷 674-682页

作者： Shahram Saeedi Maghsud Solimanpur iraj mahdavi Nikbakhsh Javadian 不详

Cellular Manufacturing System (CMS) is an application of Group Technology (GT) that allows decomposing a manu-facturing system into subsystems. Grouping the machines and parts in a cellular manufacturing system, based on simi-larities is known as cell formation problem (CFP) which is an NP-hard problem. In this paper, a mathematical model is proposed for CFP and is solved using the Ant Colony Optimization (ACO), Genetic Algorithm (GA) and Simulated Annealing (SA) meta-heuristic methods and the results are compared. The computational results show that the GA method is more effective in solving the model.

关键词： Cell Formation Problem Ant Colony Optimization Genetic Algorithm Simulated Annealing Sequence Data Production Volume