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The integration of pricing and production planning decisions has attracted many researchers and industry professionals, as these decisions directly affect the highest and lowest levels of a company. In this thesis, an integrated production-price problem for two complementary products is studied. Regarding the negative correlation of the two products, different sales strategies, including unbundling, pure bundling and mixed bundling, are used and three distinct models are proposed for each one. In the models, real and important assumptions such as production capacity limitation, shared resources, and the cost of preparation are considered. The goal of solving these models is to determine the... 

This research aims to develop and propose mathematical models that can be used to facilitate cross-functional coordination between operations and marketing. The researcher has developed a dynamic model for integrating pricing and production decisions of substitutable products in order to maximize the profit of manufacturer in multi periods. The substitution is price-driven, customer-driven and both one-way and two-way directions are considered in two different models. Demand functions are linear, determined and a function of all prices. Due to the existence of substitution between products, the price elasticity is always positive and this parameter is used as a measure of substitution in... 

The rapid growth of e-commerce and home delivery has increased the number of vehicles on the streets. As a result of that, traffic congestion and, in return, air pollution have got worse. To prevent this trend, using electric vehicles is highly suggested, and in recent years, some companies have started using autonomous delivery robots. Since these robots can travel for a limited time, it is better to use them in conjunction with other vehicles, like vans. In this research, we propose a mixed-integer programming model to formulate a two-echelon time-dependent vehicle routing problem with simultaneous pick-up and delivery. In the first echelon, vans travel from a central depot to parking and... 

Kanban inventory system has been applied as a tool of implementing lean production and just in time philosophy since three decades ago. By implementing kanban in supply chain which consist of suppliers , producers , distributors and consumers, real information of demands transfers upstream and materials flows downstream and integrated supply chain can be optained. Therefore a lot of mathematical models for optimizing kanban inventory system in supply chain has been developed to implement just in time philosophy and reduce total inventory cost in supply chain systems this research consist of two main section. In the first section , kanban and supply chain primary concepts are reviewed and... 

Mixed-model production Lines manufacture or assemble more than one product with similar production characteristics or different models of a product on the same line. This level of flexibility in commodities is very important to face diverse customers' expectations. In this article, U-shaped, mixed-model, synchronous lines with stochastic task times are discussed in a cost-oriented perspective. In U-shaped, mixed-model, Simultaneous consideration of line balancing and model sequencing is essential because different models require different tasks with different task times and the sequence of models determine the models which is produced in each station in each cycle. This sequence affects the... 

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... 

Distribution of goods by vehicle routing with split delivery and effective usage of trucks are two important problems which are useful separately and could be applied for different kinds of depots with different trucks to satisfy customers’ demand. Combination of these two NP-hard problems can play a great role to decrease transportation cost. Complexity of this problem is so much that we cannot solve big-size problems by exact methods or branch and bound method in limited time. We introduce metaheuristics methods such as Tabu Search, Simulated Annealing and Ant Colony Optimization which have been presented before, concisely. We present various constraints in routing and distribution,... 

In the intricate realm of supply chains, the ripple effect, akin to an abrupt storm, can jeopardize the stability and efficiency of the entire chain. This research aims to identify and prioritize the causative factors of this disruptive phenomenon, employing the Fuzzy Delphi Method. The Fuzzy Delphi Method is utilized in this investigation, as it possesses the capability of integrating expert knowledge with quantitative analyses. To construct the questionnaire, the results of previous studies were initially examined, and the influencing factors were identified. Subsequently, drawing upon the knowledge and experience of ten prominent experts from the "NAVABEHDASH" Organization (PANBERES), the... 

Managing the supply chain is a competitive necessity in today's global marketplace where differentiation between products and services means providing a total value package that can compete for an increasingly discerning and empowered customer. Today's view is one of integration. Supply chain management is the integrated management of business links, of information flows and of people. This research is based on a study conducted to introduce a reference model for Supply Chain integration. In that study, 10 drivers are introduced as keys for integrity in Supply Chain. The objective of this article is to discuss a method which has been developed to measure objectively and quantify the level of... 

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... 

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,... 

In this study we addressed the problem of separated waste management. Investigating the literature on location routing problem, reverse logistics, waste management, and countries’ performance in the field, we proposed a novel method for gathering household waste that inspired from prosperous metropolises and took into account the particular situations of developing countries. As a matter of fact, the proposed method is an extension of location routing problem; it’s a bi-echelon network of facilities and multi-compartment vehicles connected via reverse cross docks. The problem is formulated using a mixed-integer linear model with 3 economic, social, and environmental functions; with respect... 

This paper studies a multi-product, multi-period location- routing- inventory problem in a three-level supply chain including suppliers, cross-docks and customers. Each cross-dock could be supplied by more than one supplier and each customer could be supplied by more than one cross-dock. In the first phase we find the best locations for the cross-dock and allocate them to customers and suppliers by considering inventory costs. . Then, in the second phase Products are distributed from cross-docks towards customers using Heterogeneous vehicles. In this article the option for split delivery is enabled and furthermore, backlogging is allowable for each customer. The model presented in this... 

This paper studies a multi-product, multi-period, multi-allocation hub location problem based on real case in domestic automotive industry. As 3PL companies spread, using dynamic hubs in a contractual manner becomes passible; So in this paper the hub set is the combination of both static and dynamic hubs. The nodes are suppliers, sites and dealers of a supply chain that have certain demand of each product in each period. In this problem backlogging is allowable and causes penalty. Different transportation modes like road and railroad are usable just in hub network. Direct transmission is possible and candidate hubs are capacitated with multi suggested capacities. A mixed integer programming... 

This thesis studies a multi-commodity, multi-period three layer cross-docking network design problem. It is based on a case study in the automotive industry to optimize the flow of auto-parts from automakers to the production sites. The use of cross-docks as a facility for the aggregation point in the supply chain, allows the rapid separation of goods to be sent to demand nodes. The problem is studied in two phases; the strategic phase for the location-allocation of cross-docks and the tactical phase for the routing of heterogeneous road transportation fleet. A mixed-integer programming formulation is presented for each phase to define the problem. Genetic and harmony search meta-heuristic...