Impact Factor :
1.025
Q1(Year 2015)
ISSN : 1026-3098
e-ISSN : 2345-3605
Published Issues
Novel properties along with solution methods for permutation flowshop scheduling
2016
Abstract :
This paper deals with permutation flowshop scheduling to minimize makespan. Some novel useful definitions and properties are established. Then, the paper proposes novel solution methods. Particular attention is paid to algorithms based on the orderings of pairs of jobs. The first algorithm is for three-machine problems and gives optimal solution in a certain strict sense in the case of the ordering of two jobs. Moreover, the paper extends the three-machine Johnson’s rule to the general case of m-machine problems.
Keywords :
Scheduling; flowshops; solution methods; pairwise job-ordering, makespan
( 449 Visit ) ( 20 Download )

A two-echelon inventory model with perishable items and lost sales
2016
Abstract :
This article deals with a single perishable item, continuous-review, two-echelon serial inventory system consisting of a warehouse and a retailer. Customer demands at the retailer are assumed to be Poisson. All items have a xed shelf life and start aging on their arrival at the retailer. The demand that cannot be met immediately at the retailer is lost. All transportation times are xed. If there is any stock in the warehouse, the lead time for the retailer would be the transportation time from the warehouse. Otherwise, the retailer orders are met with a delay. In this article, using an approximate technique, we rst present a heuristic for nding cost-e ective base stock policy and then develop a simulation-based neighborhood search procedure to modify the quality of the solution. Also, a numerical experiment is carried out to evaluate e ectiveness and accuracy of the procedures. The results reveal that the approximate model performs rather well.
Keywords :
Inventory; Perishable items; Base stock policy; Lost sales; Two-echelon.
( 98 Visit ) ( 43 Download )

Resilient logistics to mitigate supply chain uncertainty: A case study of an automotive company
2016
Abstract :
Over the years, supply chain management has become more sophisticated. As supply chains become more interconnected and globalized, they also become more vulnerable, with more potential of failure and less margin of error for absorbing delays and disruptions. Since disturbances a ect the normal operation of a supply chain resulting in pro t loss and poor customer satisfaction, therefore, a resilient supply chain is critical to the success of an enterprise. Natural catastrophes and man-made disasters have signi cantly increased over the past decades. The ood in Thailand and the unexpected tsunami/nuclear leak disaster that hit northern Japan in 2011 have resulted in huge nancial losses and a decline in customer satisfaction in the car manufacturing industries in Asia Paci c and North America. To overcome the increasing uncertainty which resulted from these disasters, a study to identify risk mitigation strategies for an automotive industry is timely. Our objective was to reduce the losses due to possible disasters using an automotive industry as a case example.
Keywords :
Process mapping; Program Evaluation and Review Technique (PERT); Resilient; Supply chain management.
( 53 Visit ) ( 11 Download )

Optimal Multi-Products Dynamic Pricing and Inventory Policies for Coordinating Production and Marketing under Fuzzy Environment: Fuzzy Expansion Methods
2016
Abstract :
This paper investigates the optimal multi-products dynamic pricing and inventory policies over a multi-period planning horizon with deteriorating products and a fuzzy demand function. The objective is maximization of the discount profit. A dynamic programming model is presented to determine retail price and replenishment quantities. Also, due to the existence of uncertainties in the parameter values such as cost, deterioration rate, and the optimal strategies in general, it cannot be obtained with high feasibility. So, the concept of fuzzy set theory can be applied to cope whit this issue. Since the presented model is a fuzzy partial differential equation, three novel fuzzy expansion methods including Jacobi polynomials, airfoil polynomials, and fuzzy collocation methods are proposed for solving this problem. Finally, this paper carries out various computational experiments to assess the proposed model and solution approaches.
Keywords :
Dynamic programming; Pricing-inventory policies; Uncertainty; Fuzzy expansion method
( 405 Visit ) ( 38 Download )

Optimal replenishment policy with variable deterioration for fixed lifetime products
2016
Abstract :
This model illustrates an inventory model to obtain the retailers optimal replenishment policy for deteriorating items with fixed lifetime, shortages, and time- dependent backlogging rate. The backlogging rate is considered as non-increasing function of waiting time up to the next replenishment. Our intention is to minimize the total relevant cost of the system. Further, the necessary and sufficient conditions are derived for the existence and uniqueness of the optimal solution. Finally, some numerical examples, sensitivity analysis along with graphical representations are provided to illustrate the proposed model. From the numerical example, we prove more savings than Wu et al. (2006).
Keywords :
Inventory; time-varying deterioration; variable demand; partial backlogging.
( 40 Visit ) ( 4 Download )

Supply chain coordination via two-way cooperative advertising contract considering competing retailers
2016
Abstract :
This article addresses an optimization problem using Game Theory in an advertising environment where decisions regarding the advertising expenditure of a supply chain members must be determined. We study a cooperative (Co-op) advertising problem in a channel comprising of one manufacturer and two competing/cooperating retailers. The manufacturer leads the channel and Stackelberg game is played between the echelons. Moreover, the retailers in the downstream echelon can adopt either Collusion or Stackelberg behavior. The possibility of coordination via a two-way subsidy strategy is discussed under two scenarios in which either the participation rates are exogenously specified or the members endogenously decide on these rates. It is shown that the perfect coordination of the channel is obtained via two-way subsidy strategyin the exogenous scenario;furthermore, under the endogenous scenario, with the whole system point of view, the two-way subsidy strategyis superior to the traditional one-way strategy.
Keywords :
cooperative advertising; coordination; contract design; competing retailers; game theory
( 702 Visit ) ( 52 Download )

A bi-objective mathematical model for dynamic cell formation problem considering learning e ect, human issues, and worker assignment
2016
Abstract :
One of the important aspects neglected in the literature related to cell formation problem is human issues. In this study, a bi-objective mathematical model is developed in which human issues and dynamic cell formation are taken into consideration simultaneously. The rst objective function deals with costs associated with machines and human issues. The costs of human issues relate to salary, hiring, ring, reward/penalty policy, and worker assignment. The second objective function takes into account labor utilization as a criterion for reward/penalty policy. Since the available time in di erent real conditions is not constant, we include learning e ect to consider the real workers time. The nature of dynamic cell formation problem is NP-hard, and thus a Linear Programming embedded Genetic Algorithm (LP-GA) is employed to solve the model. In order to improve the performance of the applied GA, its parameters are tuned by means of Central Composite Design (CCD) method. Moreover, to validate the LP-GA, some test problems are solved and the results are compared with those obtained from an exact method and GA. The computational results show that the near optimal solutions yielded by LP-GA are better than GA in large-sized problems.
Keywords :
Dynamic cell formation; Human issues; Linear programming; Genetic algorithm; Central composite design.
( 57 Visit ) ( 24 Download )

A Novel Interval Type-2 Fuzzy AHP-TOPSIS Approach For Ranking Reviewers in online communities
2016
Abstract :
Online product review websites have become excellent platforms for customers to share their opinions about a variety of products and services in the form of online reviews. Despite being an invaluable source of information for both consumers and firms, the quality of online reviews varies greatly. To tackle the problem of low quality reviews, in this paper, we address reviewer credibility problem and propose a novel framework for ranking reviewers in terms of credibility based on interval type-2 fuzzy analytical hierarchy (IT2 FAHP) and technique for order performance by similarity to ideal solution (TOPSIS). The novel IT2 FAHP is used to determine weights of features representing reviewers where the interval type-2 trapezoidal fuzzy numbers are used predominantly and TOPSIS method is used to obtain final ranking of reviewers. To illustrate an application of the proposed framework, we conducted an experimental study using real data crawled from Epinions. This proposed framework provides a more effective and systematic approach especially for firms to find high-credible reviewers and to select their reviews and opinions for opinion mining.
Keywords :
Customer Review; Reviewer Credibility; Fuzzy AHP; Interval type-2 Fuzzy AHP; TOPSIS
( 701 Visit ) ( 41 Download )

Bayesian analysis of type-I right censored data using the 3-component mixture of Burr distributions
2016
Abstract :
This study is concerned with the problem of estimating the parameters of a 3-component mixture of Burr distributions using type-I right censored data.The closed form expressions for the Bayes estimators and their posterior risks assuming the non-informative (uniform and Jeffreys’) priors under squared error loss function, precautionary loss function and DeGroot loss function are derived.Performance of the Bayes estimators for different sample sizes, test termination times(a point of time after which all other tests are terminated)and parametric values under different loss functions is investigated. The posterior predictive distribution for a future observation and the Bayesian predictive interval are constructed. In addition, the limiting expressions for the Bayes estimatorsand posterior risks are derived.Simulated data sets are designed for thecomparisons and the model is finally illustrated using the real data.
Keywords :
Bayesian analysis; Burr distribution; Uniform and Jeffreys’ priors; Posterior risk; Predictive interval; Censored data
( 644 Visit ) ( 123 Download )

A differential Stackelberg game for pricing on a freight transportation network with one dominant shipper and multiple oligopolistic carriers
2016
Abstract :
This paper studies dynamic pricing and freight network equilibrium problem on a system consisting of one dominant producer called the shipper and multiple oligopolistic carriers who serve the shipper’s origin-destination orders. The shipper sells a homogeneous commodity to spatially separated demand markets. The demand received by the shipper is price sensitive while the prices set for each market is influenced by the pricing strategies of the oligopolistic carriers. We formulate the problem as a differential Stackelberg-Nash game to find the equilibrium production, price and routing decisions over a planning horizon. A finite dimensional discretization method and a penalty function algorithm are proposed to solve the model. The existence and uniqueness properties are also explored. Finally, some numerical examples are presented and a comprehensive sensitivity analysis on the critical parameters is conducted to show the efficiency of the proposed model and solution method.
Keywords :
Dynamic pricing, Differential game, Stackelberg-Nash equilibrium, Bi-level programming, Freight network equilibrium
( 366 Visit ) ( 63 Download )

Pricing and Ordering under Trade Promotion, Brand Competition and Demand Uncertainty
2016
Abstract :
In practice,many manufacturers offer trade promotion to retailers to induce demand. It is also common for a retailer to sell products from competing manufacturers. This paper considers a two-echelon supply chain where two manufacturers provide a trade promotion to a retailer and the retailer faces uncertain and price-dependent demand.In the model, the manufacturers determine wholesale prices and the retailer determines retail price and order quantity to maximize their own profits. An algorithm based on nonlinear optimization is provided to solve the problem. We compare three trade promotions under brand competition: off-invoice, scan-back and buy-back policies, and discuss the effects of trade promotions on decisions and profits.The results indicate that the manufacturers and retailer prefer the buy-back policy over the off-invoice and scan-back policies. The retailer’s profit will increase and the manufacturers’ profits will decrease as the brand substitution effect increases. Also, the manufacturers will raise their wholesale prices but the retailer will reduce the retail price and order quantity when the brand substitution rate increases.
Keywords :
pricing; inventory;brand competition; demand uncertainty; piecewise nonlinear
( 601 Visit ) ( 25 Download )

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Published Issues
2016
2015
Transactions on Civil Engineering
Transactions on Mechanical Engineering
Transactions on Chemistry and Chemical Engineering
Transactions on Computer Science & Engineering and Electrical Engineering
Transactions on Industrial Engineering
Transactions on Nanotechnology
2014
Transactions on Civil Engineering
Transactions on Mechanical Engineering
Transactions on Chemistry and Chemical Engineering
Transactions on Computer Science & Engineering and Electrical Engineering
Transactions on Industrial Engineering
Transactions on Nanotechnology
2013
Transactions on Civil Engineering
Transactions on Mechanical Engineering
Transactions on Chemistry and Chemical Engineering
Transactions on Computer Science & Engineering and Electrical Engineering
Transactions on Industrial Engineering
Transactions on Nanotechnology

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