فهرست مطالب

Iranian Journal Of Operations Research
Volume:7 Issue: 1, 2016

  • تاریخ انتشار: 1395/01/30
  • تعداد عناوین: 6
|
  • Abdollah Arasteh Dr * Page 1
    Here, issues connected with characteristic stochastic practices are considered. In the first part, the plausibility of covering the arrangements of an improvement issue on subjective subgraphs is studied. The impulse for this strategy is a state where an advancement issue must be settled as often as possible for discretionary illustrations. Then, a preprocessing stage is considered that would quicken ensuing inquiries by discovering a settled scattered subgraph covering the answer for an arbitrary subgraph with a high likelihood. This outcome is grown to the basic instance of matroids, in addition to advancement issues taking into account the briefest way and resource covering sets. Next, a stochastic improvement model is considered where an answer is sequentially finished by picking an accumulation of “points”. Our crucial idea is the profit of adaptivity, which is investigated for an extraordinary sort of an issue. For the stochastic knapsack issue, the industrious upper and lower cutoff points of the “adaptivity hole” between ideal adaptive and non-adaptive methodologies are checked. Also, an algorithm is described that accomplishes a close ideal estimate. Finally, complicational results are shown to verify the optimal adaptive approaches.
    Keywords: Stochastic optimization, Probabilistic methods, Stochastic knapsack, Matroids
  • Kourosh Eshghi *., Mohsen Salarrezaei Page 2
    First, an integer programming model is proposed to find an α-labeling for quadratic graphs. Then, a Tabu search algorithm is developed to solve large scale problems. The proposed approach can generate α-labeling for special classes of quadratic graphs, not previously reported in the literature. Then, the main theorem of the paper is presented. We show how a problem in graph theory can be modeled and solved by an integer programming model and a metaheuristic approach.
    Keywords: Graph labeling, α-labeling, Quadratic graphs, Integer programming, Tabu search algorithm
  • Saiedeh Gholami Dr *, Mahdi Jalalian, Reza Ramezanian Dr Page 3
    In the past decade, fuel consumption and CO2 emission have increased in the airline industry. Large CO2 footprint has a damaging effect on the environment. Global concerns over this issue has made the airline industry to be greener. Most efforts of the green airline industry are improving the fuel consumption to reduce the CO2 emission and its environmental damage. Here, we use cruise speed control to control the fuel consumption and CO2 emission. Each aircraft has a different speed level needing a different fuel consumption. Service quality is studied besides the energy consumption. We investigate two objectives including total energy consumption (TEC) and passenger service level (PSL). TEC and PSL are conflicting in nature. We develop a mixed-integer nonlinear programming model to integrate schedule design, aircraft assignment and maintenance routing problems. We make use of the augmented ε-constraint method to solve the problem. To evaluate the model, a real data based on the Emirates airline flights is used. The results are compared using four different scenarios
    Keywords: green airline, CO2 emission, cruise speed control, schedule design, aircraft assignment, maintenance routing
  • Mahdi Shafiei *, Mohammad Modarres Page 4
    We develop a new coordination contract of manufacturer-retailer in a distribution system. A revenue sharing contract based on retail price is modelled, which is more practical to handle channel conflict. We also integrate two concepts of CSR (Corporate Sociality Responsible) and Semi-TDPD (Semi Third Degree Price Discrimination) into our model. Semi-TDPD strategy makes it possible to exploit the opportunity of customer behavior, by adopting a price discrimination strategy. According to this strategy, some customers who cannot or are not willing to pay the posted price, are allowed to purchase at lower prices through bargaining. To illustrate the proposed approach, we present some numerical examples. Through these examples, we investigate the impact of CSR and Semi-TDPD on decisions and also the good performance of this coordination.
    Keywords: Revenue sharing, Distribution channel, Pricing, CSR, Semi-TDPD, Stackelberg game model
  • Davood Shishebori Dr * Page 5
    We consider the reliable multi configuration capacitated logistics network design problem (RMCLNDP) with system disruptions, concerned with facilities locating, transportation links constructing, and also allocating their limited capacities to the customers in order to satisfy their demands with a minimum expected total cost (including locating costs, link constructing costs, as well as expected transshipment costs in usual and disruption conditions). The motivating application of this class of problem is in capacitated logistics network design with multi configuration (including multi-product, multi-vehicle, and multi-type link) regarding system disruptions simultaneously. The problem is modelled as a mixed integer program. Also, a hybrid heuristic algorithm is proposed. The algorithm, as an efficient approach, is a hybridization of sample average approximation, the LP relaxation, and a two stage decomposing heuristic. The results of a detailed comprehensive computational analysis are also reported. Computational experiments illustrate that the provided algorithm is able to substantially outperform the integer programming approach in terms of both finding and verifying the efficient optimal (or near optimal) solutions at reasonable processing times.
    Keywords: Multi-product, Multi-type transportation links, Multi-vehicles, Multi configuration, Capacitated logistic network design, Disruptions, Reliability, Two stage decomposing heuristic, LP relaxation, Sample average approximation (SAA)
  • Ata Allah Taleizadeh Dr *, Hossein Salehi, Luis Augusto San-JosE Page 6
    We consider a three-level distribution network involving a raw material supplier with imperfect quality, a manufacturer and several retailers. A production-inventory model accompanied by a partial backlogging approach is developed by considering random disruptions. Any batch received from the supplier is inspected by the manufacturer and if any flaw is visited, all the goods in the inspected batch are rejected. The aim is to minimize the total cost. A heuristic algorithm is presented to compute the optimal policy.
    Keywords: Inventory management, EPQ, Partial backlogging, Disruption, Supply chain