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We probably can say all people that are familiar with industrial engineering, have some information about supply chain management. Of course some people have more information about it and some have less. However, it is expected that they have some information about logistics because logistics is one of the most important elements in supply chain management. But it is sure that they have no information or less information about reverse logistics. That is why I have chosen this subject as my thesis. I have presented an optimization model with a numerical example  

Logistics performance is one of important factors in economic growth of a country. Many firms in all over the world outsourcing their logistics activities to third party logistics companies (3PL) in order to gain higher performance and reduce time and cost of logistics services. Important role of 3PL companies and lack of them in Iran’s logistics industry were the main drives of this of this thesis. In this thesis after introduction and literature review, the main question of thesis will be defined this is about advantages of using 3PLs in Iran logistics industry and structure of them. To find the answer, based on information and statistical reports from world bank, Iran logistics... 

In this thesis, an inventory- location model considering capacity constraints and coverage radius is described in which the capacity is determined based on the maximum accumulation inventory. This model, through minimizing the sum of the fixed facility location costs, transportation costs and safety stock and working inventory costs, concurrently, determines warehouse location, assignment of retailers to warehouses, shipment sizes from the plant to warehouses, working inventory and safety stock levels at the warehouses. This problem can be formulated as a nonlinear mixed integer program in which the objective function is neither concave nor convex. Lagrangian relaxation is incorporated for... 

Using the cross docking is a strategy that plays inventory coordinating role in the supply chain. At the cross docking, products of inbound trucks are unloaded, sorted, moved and loaded onto outbound trucks for delivery to different destinations. In this concept, coordination between inbound and outbound trucks considering a cross-dock system with multiple receiving and shipping dock doors. Moreover, due to justifiability of all trucks to carry multiple product types, product assignment from inbound trucks to outbound trucks is determined simultaneous to scheduling. As an exact solution approach a MIP model is presented and since the problem is shown to be NP-hard, it can only be used to... 

Cross-docking is an innovative logistic strategy which brings significant advantages in-cluding little or no inventory in the warehouse. In this concept, coordination between in-bound and outbound trucks is quite important. This research studies the scheduling prob-lem of inbound and outbound trucks considering a cross-dock system with multiple receiv-ing and shipping dock doors. Moreover, due to justifiability of all trucks to carry multiple product types, product assignment from inbound trucks to outbound trucks is determined simultaneous to scheduling. As an exact solution approach a MIP model is presented and since the problem is shown to be NP-hard, it can only be used to solve small... 

Optimizing multi-period modern distribution system is a challenging task due to high costs of constructions in urban areas and importance of fast and cheap goods delivery to customers. Various logistic techniques have been proposed to solve this issue. In this study, a new method is suggested to convert the strategic problem of finding depot location into a tactical problem. In addition, a vehicle routing method for multi-period distribution systems in high demand periods have been developed. For modeling this location-routing problem two objective functions have been considered as fallows minimizing the total time in the system to satisfy customer demand and operating costs. To solve this... 

The main purpose of this Thesis is to study logistics situation of L90 production site at Iran khodro Co. and improving it to achieve the project and investment goals. Some proposals in the fields of plant layout redesign, inbound logistics, material flow analysis, and Kanban and synchrony systems development are offered. Plant layout optimization based on allowing facilities parting into more than one section is studied and its mathematical model is developed. A heuristic alogorithm for this type of FLP’s has been offered which optimizes a given solution. The propsed methodology is applied on a real case-Iran khdro L90 site and the obtained solution indicates good results of the algorithm.... 

The growth of road freight transport in recent years, in addition to positive effects, has also left negative externalities. Part of the negative effects such as environmental pollution and damage to infrastructure is exacerbated by the lack of capable transport companies and the low productivity of transportation systems. The government intervenes through regulatory scenarios such as restrictions and tolls to reduce the negative effects on the road transport market. But which scenario is more effective in improving the productivity of the current transportation structure and what will be the consequences? This paper introduces an agent-based micro-simulation to model domestic trucking... 

Regarding to emergence of the globalization concepts in manufacturing, technology and information technology has come to aid of the organizations to expand communication across the globe, in order that companies can overcome many of their deficiencies in this way. To achieve this goal, Cloud Manufacturing (CMfg) system have been investigated, while today the CMfg is a new manufacturing paradigm and is one of the dominant concepts in manufacturing industries. Regarding to the nature of the cloud, the resources used to meet the customer demands are not necessarily concentrated in a specific geographic location, or the demand of a customer may not be satisfied with a distinct service, as a...