Sharif Digital Repository

In this research, we propose a formulated approach to locate and allocate two level of a three-level closed-loop supply chain consist of a number of capable points production facilities, redistribution centers and customer clusters for multiple products in multiple time periods. Also, we consider environmental aspects in this supply chain network by taking into account an objective function, aside from cost objective function, in the template of emitted carbon dioxide. In this research for the first time we consider vehicles’ emitted CO2 different in each period which is a result of gradual depreciation of vehicles. In the end for the sake of validating model’s performance we developed few... 

Environmental problems and the consequent governmental regulations, has led supply chains into reverse and closed-loop supply chains. Application of problems such as "Vehicle Routing Problem” has diminished in the closed-loop supply chain, and instead of them, the problem of "Vehicle Routing Problem with Deliveries and Pickups" has become more important. On the other hand, tendency of supply chains to running information in the chain in a desired way, has led to grow the attention to establishing policies of “Vendor Managed Inventory". It seems that by tending the supply chains to closed-loop supply chains which are utilizing the policy of "Vendor Managed Inventory", application of problems... 

Pooling Lead-time risk by splitting replenishment orders simultaneously among multiple suppliers is a sourcing policy that has attracted the attention of academic researchers for some years. While they consider many different assumptions in their models, they don’t pay attention to deterioration items in order splitting models. In this thesis, we have considered order splitting policy about products with constant deteriorating rate and developed two inventory models. In the first model, it is assumed that the whole requirement supply from only one source, whereas in the second two suppliers are accessible. Then after determining the optimal policy, by numerical search and use of MAPLE... 

In recent years, Supply Chain Management has become one of the most desired concepts for Industrial engineers. In this thesis, specifically, one of the SCM’s aspects, Joint Economic Lot Sizing1, which in literature have been studied by various people with different viewpoints, is considered and a two-stage supply chain facing certain demands is studied. These demands are changing as a function of selling price determined by a supply chain and the goal is to increase the chain’s total profit in comparison of individual policies in which members decide about their profits separately. The optimal amount of selling price varies end-customer demands exponentially and leads to changes in economic... 

Inventory problems are studied for a long time and many authors have investigated models with shortage phenomenon. To reduce inventory holding cost or decaying items we can have a shortage period in witch a part of demand is backordered; Although we pay fines to pending costumers, as shortage period is extended a larger portion of them will refuse to wait until replenishment. So, calculating an optimal duration for on hand inventory and shortage period with respect to inventory costs has became an interesting research field. However, related studies are rarely appeared in supply chain researches, where an integrated inventory model for a supplier and a retailer is proposed; especially when a... 

Locating wireless transmitters is one of the most important issues. That’s why many researchers have worked in this subject recently. Communication Engineers always want to optimize the productivity of wireless transmitters. They prefer to cover a region completely by minimum cost, so they use analytical tools for solving this kind of problems. This type of optimization is very useful for cellular Networks. There is a different kind of wireless services such as high-speed Internet services; their goal is maximizing the covered demand points by minimum cost not covering all of them. Experts use maximal covering location problem for modeling this kind of problems. At first, an extension of one... 

Refer to increasing importance of logistic and influences of it on economy improvements and increasing the number of third party logistic users in all around the world and also lack of such companies in Iran, this thesis is going to discuss about feasibility study for using TPLs in automotive industry. After study and review on literature and statements of the subject and representing features of TPLs compared with other logistic companies and identifying important logistic companies, this thesis is going to identify local and over the seas companies and study them, study current rules and regulations in country and present legal defects for TPL companies. Finally it represent the technical... 

Today, using Radio Frequency Identification (RFID) technology is of a remarkable interest to the industry and services sectors. Application of this technology could result in higher levels of productivity and effectiveness. On the other hand, department stores are increasing in number and size in the country. Application of RFID technology could play an undeniable role in both reducing the time each customer must spend in order to complete their purchase, and accelerating the logistics operations of these stores.
Through literature review, this research studies application of RFID technology instead of other identification technologies such as Bar-Code, reveals strengths and weaknesses... 

The hub networks are applied for commodity flows in the systems, among whose nodes the direct connections are both impossible and expensive. The dependency and interaction of demands are dealt with in this thesis. The dependency of demands are the results of some significant aspects, the most important of which are selecting or not selecting a node as a station, allocating or not allocating a demand to a hub, and associating with a path, to name but a few. Then, the ideas of hub location problem, interaction model, and eventually commodity transportation have been considered together.
In this master thesis, a model having a quadratic and non-linear objective function has been developed.... 

In decentralized Supply Chains, each member decides based on his own interests. Conflict of interests results in suboptimal decisions and poor performance for entire supply chains, as well seriously harms credibly information sharing across them. In this thesis, coordination of decisions in supply chains in the context of Capacity Procurement problem are studied in different situations in form of three models. In first model, a dyadic supply chain with stochastic demand and exogenous price is investigated by taking various costs into account. PARD and RCRS contracts are designed and proposed in order for coordination of decisions respectively in full and partial information updating... 

Logistics includes the flow of goods, information and other sources between production and consumption node to meet the demand of customers. Basically, Logistics includes the integration of information, transportation and inventory. This study is in association with how to phase-out the old product when the new one is developed, and also is about how to manage the remaining inventory in a phase-out period focusing on such decisions as time and discount amount. Often in retailing system, old products have been phased out with an introduction of a new one by distributors. In order to sell this amount of products in a specific time period retailers need to create a mechanisim to phase-out the... 

This study aimed to develop a green network design for a multi-echelon multi-product supply chain with a focus on bottleneck points as the means of enhancing unutilized capacities to maintain the optimal levels of flexibility. Two different models were developed to compare different approaches of flexible capacity planning by minimizing the total cost of facility establishment as well as their utilization and transportation cost. The proposed mixed-integer linear programming model was characterized by its novelty in taking bottleneck points into account to build a platform for flexible capacity planning required for responding to uncertainties such as fluctuations in demand and new product... 

Nowadays, increasing of difficulties in production and procurement conditions such as competitiveness among manufacturing firms, variety of products, rapidly changing of customer tastes, shortening of product lifetime and complexity of demand forecasting on one hand, and key role of consumers and deteriorating products on countries revenue on the other hand, make replenishment policies of deteriorating products challenging and also interesting for both researchers and corporate managers.In this dissertation several novel models on replenishment policies for deteriorating products are proposed under uncertainty by the help of single or multi objective mathematical models. One important... 

Single floor facility layout problem (FLP) is related to finding the arrangement of a given number of departments within a facility; in multi-floor FLP, the departments should be imbedded on some floors which are inside the facility. The significant influence of layout design on effectiveness of any organization has made FLP an important issue. This paper presents a three (two) stage mathematical programming method to find competitive solutions for multi (single) floor problems. The first stage assigns the departments to the floors by using a mixed integer programming model (the single floor version does not require this stage). The second stage uses a nonlinear programming model to specify... 

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... 

This thesis studies a multi-product location-routing-inventory problem in which location-allocation, inventory and routing decisions are to be taken in a three-level supply chain including suppliers, depots and customers. Each product for each depot could be supplied by more than one supplier and each supplier has a limited supplying capacity per period. Products are distributed from depots to customers by a homogeneous fleet of vehicles. Backlogging is allowable for each customer on the condition of not exceeding a fraction of customer’s demand. A mixed-integer programming formulation is presented to describe the problem then a new hybrid heuristic algorithm based on the simulated annealing... 

Success in a business will be met by the different factors, of which one of the most important is design and execution of a good business model upon the inauguration of each company. Indicating the commercialization of innovations and innovative commercial ideas, it shows the productivity of innovation. Outsourcing the Training management in organizations is an issue the world pioneer organizations feel its necessity. Training systems in organizations have limited resources, don't have the required knowledge and financial sufficiency for effective execution of all Training processes. Therefore, Training management outsourcing may be a good alternative for meeting perspective and facilitating... 

In this thesis, two Inventory-Routing Problem models, under vendor managed inventory policy are presented. In the first proposed model, despite the previous researches, transshipments between retailers are permitted and the problem is modeled by the assumption of reverse flow in the distribution network. Based on the first model, we also formulate a new model for the Pallet managing problem. Since the inventory routing problem is known as NP-Hard, genetic and variable neighborhood search algorithm has been applied to determine an acceptable upper bound for the first model in different instances. In the next step a Lagrangian relaxation method is developed for finding a near optimal solution... 

Logistics activities and matters related to supply chain management play an important role in the success of supply chain in today’s competitive business environment. The success of an organization depends on the proper functioning of the whole supply chain organization. SCOR model as a reference model for supply chain management is a suitable framework to manage all aspects of the supply chain and enables the creation of an appropriate and efficient structure in supply chains. In this thesis the Procurement department of a petrochemical company is examined and the current state of the supply chain is explained and then based on the SCOR model, in 4 areas: Performance (indices), Processes,...