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vehicle-routing-problems
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A new approach to solve MDVRP in lower computation time
, Article 29th Iranian Conference on Electrical Engineering, ICEE 2021, 18 May 2021 through 20 May 2021 ; 2021 , Pages 632-636 ; 9781665433655 (ISBN) ; Zajkani, M. A ; Haeri, M ; Sharif University of Technology
Institute of Electrical and Electronics Engineers Inc
2021
Abstract
Vehicle routing problem is one of the complex and NP-hard problems, which plays a crucial role in this hectic world regarding people's lifestyle. Nowadays, many people provide their stuff online, so a logistic problem has been outstripped for companies to reduce their transportation costs. In this article, a novel approach has been introduced, which can solve the multi-depot vehicle routing problem in shorter time. By using clustering and decomposing the main problem into smaller ones, solution time has been dropped dramatically. In addition, this approach obtains a reasonable cost, which can be considered as fuel consumption, distance, or so forth. This method could reduce the solution time...
Approximation Algorithms for the Heterogeneous Vehicle Routing Problem
, M.Sc. Thesis Sharif University of Technology ; Zarrabi-Zadeh, Hamid (Supervisor)
Abstract
In this thesis, we study the heterogeneous vehicles routing problem, which is a general-ization of the well-known travelling salesperson problem. In this problem, we are given a set of heterogeneous vehicles located in specific depots, along with a set of customers in the form of a graph. The vertices of the graph represent clients and depots, and the weight of edges represents the cost of travel between vertices of the graph. The goal is to find a subgraph for each vehicle so that the union of the subgraphs contain all customers and the total travel cost is minimized. The heterogeneity here means that the cost of traversing edges for each vehicle might be different. In this work, we briefly...
A heuristic approach for periodic vehicle routing problem: A case study
, Article International Journal of Logistics Systems and Management ; Volume 8, Issue 4 , 2011 , Pages 425-443 ; 17427967 (ISSN) ; Safaei, N ; Assadi, P ; Sharif University of Technology
Abstract
A heuristic approach is proposed to solve a real Periodic Vehicle Routing Problem (PVRP) that aims at extending the market share with the minimum transportation cost. In PVRP, vehicles are assigned to routes in different workdays to satisfy the frequency of visiting customers. The objective is to determine the scheduling and routing policies of the vehicles to minimise the fleet size and to maximise the selling benefits. The vehicle capacity and the trip time are the main constraints. The proposed approach is verified by real data and obtained results imply a significant improvement as compared to the current status
A fuzzy mathematical model for supplier selection and order allocation considering green vehicle routing problem
, Article International Journal of Logistics Systems and Management ; Volume 27, Issue 2 , 2017 , Pages 151-163 ; 17427967 (ISSN) ; Kianfar, F ; Sharif University of Technology
Inderscience Enterprises Ltd
2017
Abstract
Recently, with the expansion of environmental issues and raising of customers' awareness, companies are experiencing huge pressure from shareholders and the government for greater compatibility with their environment. Companies and industry owners must implement green operations in their daily activities to be able to keep up with the competitive atmosphere of the environment. One of the most important operations to be implemented is cooperating with green suppliers. In this study, a multi-objective mathematical model is proposed to select suppliers and allocate optimal orders to them in a two-echelon supply chain, including supply and distribution echelons. The proposed model focuses on the...
A Multisource Location-routing-inventory Problem with Backlogging
, M.Sc. Thesis Sharif University of Technology ; Akbari Jokar, Mohammad Reza (Supervisor)
Abstract
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...
Disaster Relief Routing Under Uncertainty: a Robust Optimization Approach
, M.Sc. Thesis Sharif University of Technology ; Mahdavi Amiri, Nezamoddin (Supervisor)
Abstract
In this thesis, we consider the capacitated vehicle routing problem (CVRP) and the split delivery vehicle routing problem (SDVRP), with uncertain travel times and demands in the process of planning vehicle routes for delivering critical supplies to the affected population in need after a disaster. A robust optimization approach, introduced in the literature, is used for CVRP and SDVRP, in which, as Li and Chung have done, five objective functions are considered: minimization of the total number of vehicles deployed (minV), the total travel time/travel cost (minT), the summation of arrival times (minS), the summation of demand-weighted arrival times (minD), and the latest arrival time...
Multi Commodity Three Layer Cross-docking Network Design Problem
, M.Sc. Thesis Sharif University of Technology ; Akbari Jokar, Mohammad Reza (Supervisor)
Abstract
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...
The Multi-Depot Traveling Purchaser Problem with Shared Resources
, Ph.D. Dissertation Sharif University of Technology ; Eshghi, Kourosh (Supervisor) ; Rafiee, Majid (Supervisor)
Abstract
The Multi-Depot Traveling Purchaser Problem under Shared Resources (MDTPPSR) is a new variant of the Traveling Purchaser Problem (TPP). In this problem, each depot can purchase its products using the shared resources of other depots, and vehicles do not have to return to their starting depots. The routing of this problem is a Multi-Trip, Open Vehicle Routing Problem. A tailored integer programming model is formulated to minimize the total purchasers’ costs. Considering the complexity of the model, we have presented a decomposition-based algorithm that breaks down the problem into two phases. In the first phase, tactical decisions regarding supplier selection and the type of collaboration are...
Distribution Problem Considering Effective Usage of Trucks
, M.Sc. Thesis Sharif University of Technology ; Akbari, Mohammad Reza (Supervisor)
Abstract
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,...
Adaptive Modelling and Solution of Drone Logistic Service Composition in Cloud Supply Chain Considering Dynamic Condition
, M.Sc. Thesis Sharif University of Technology ; Hoshmand, Mahmoud (Supervisor)
Abstract
globalization has let suppliers to geographically distribute across the globe, and for accomplishing the final product resources need to be gathered. So, Cloud manufacturing is a new paradigm which provides ubiquitous, convenient, on-demand network access to a shared pool of configurable manufacturing resources distributed across the globe. On the other hand, in recent years the product delivery system has faced a significant amount of changes with reducing cost and waiting time of last-mile delivery. Unmanned aerial vehicles, or drones, have the potential to deal with these issues effectively. This research developed a mathematical formulation to investigate the optimum routing and...
A New Model for Vehicle Routing Problem (VRP) Considering Cross Docking Services in Cloud Manufacturing Systems
, M.Sc. Thesis Sharif University of Technology ; Fatahi Valilai, Omid (Supervisor)
Abstract
Nowadays, the modern manufacturing dramatically has changed due to the intense global competition and the globalization of economics, resources, and rapid progress in manufacturing systems, information, computer and information management. Cloud manufacturing systems are a new network-based manufacturing paradigm which by utilizing cloud computing and service generation enables technologies to transfer manufacturing resources into manufacturing services. Moreover, recent researches have shown that security, reliability, and quality are enhanced by cloud computing systems. In cloud manufacturing systems, resources that are located in different geographic points enable the distribution of...
Vehicle Routing Problem with Environmental Considerations
, M.Sc. Thesis Sharif University of Technology ; Eshghi, Kourosh (Supervisor)
Abstract
Transportation services enable economic growth of countries and account as a major part of Gross National Product (GNP) but on the other hand have negative environmental impacts including Greenhouse Gas (GHG) emissions, noise pollution and toxic effects on the ecosystem such as acid rain. The traditional objective of distribution management is usually minimizing economic costs. Given the existing environmental problems, ecological and social effects of transportation should be considered in addition to the conventional economic costs. In this study, a special type of Vehicle Routing Problem (VRP) with a heterogeneous vehicle fleet that in which environmental and traffic considerations taken...
Vehicle and Drone Routing for Relief Operations
, M.Sc. Thesis Sharif University of Technology ; Haji, Alireza (Supervisor)
Abstract
The use of drones in various fields is increasing. One of the applications that can be mentioned for drones is humanitarian areas can include drug supply chains, blood supply chains, relief chains, and the like. The use of these unmanned vehicles in humanitarian areas poses legal challenges compared to other areas. This study aimed to investigate drones following a disaster, the essential role of UAVs, and a vehicle to carry out relief operations. Following a disaster, infrastructure can be severely damaged, and the destruction of infrastructure can reduce the efficiency of land vehicles. In this research, “drone and vehicle routing problem” have been done to provide relief and minimize the...
Solving a Flexible, Multi-Objective Multi-Depot VRP and IRP Considering 3DP and Sustainability with Several Levels in the Transportation Network
, M.Sc. Thesis Sharif University of Technology ; Haji, Alireza (Supervisor) ; Fatahi Valilai, Omid (Supervisor)
Abstract
A sustainable supply chain requires constant sustainable changes in the design and performance of its steps. The main characteristic of sustainability is the consideration of social, environmental and economic criteria in strategic and operational decisions. Due to the great importance of the sustainability in transportation network, proper planning and careful design for this issue in recent years has been considered and welcomed by relevant researchers. In this research we want to provide an integrated frame work for transportation network design toward sustainability. In this regard, we also use 3D printing technology as our innovation in operations. Our main issue is the Inventory...
The multi-depot traveling purchaser problem with shared resources
, Article Sustainability (Switzerland) ; Volume 14, Issue 16 , 2022 ; 20711050 (ISSN) ; Eshghi, K ; Rafiee, M ; Van Woensel, T ; Sharif University of Technology
MDPI
2022
Abstract
Using shared resources has created better opportunities in the field of sustainable logistics and procurement. The Multi-Depot Traveling Purchaser Problem under Shared Resources (MDTPPSR) is a new variant of the Traveling Purchaser Problem (TPP) in sustainable inbound logistics. In this problem, each depot can purchase its products using the shared resources of other depots, and vehicles do not have to return to their starting depots. The routing of this problem is a Multi-Trip, Open Vehicle Routing Problem. A tailored integer programming model is formulated to minimize the total purchasers’ costs. Considering the complexity of the model, we have presented a decomposition-based algorithm...
Multi-depot Vehicle Routing Using Predictive Distributed Cooperative Method
, M.Sc. Thesis Sharif University of Technology ; Haeri, Mohammad (Supervisor)
Abstract
Due to conspicuous increases in shopping and goods transportation in this unbridled world, a significant part of companies’ final interest and final cost are related to their distributions of goods. Meanwhile, because of practical constraints of service hours and service distances, logistics companies usually build multiple depots to serve a great number of dispersed customers. Hence, multi-depot vehicle routing problems (MDVRP) win more and more engineers’ and companies’ attention to thrift their cost by using optimization methods. Considering NP-hardness of MDVRP and the lack of optimal solution derived by heuristic and meta-heuristic approaches in the large scale problems, in this...
Vehicle Routing Problem with Simultaneous Pickup and Delivery and Maximum Tour Time Length Constraint
, M.Sc. Thesis Sharif University of Technology ; Akbari Jokar, Mohammad Reza (Supervisor)
Abstract
The Vehicle Routing Problem with Simultaneous Pick-up and Delivery (VRPSPD) and maximum time for traversing of each tour is a variant of the classical vehicle routing problem (VRP) where clients require simultaneous delivery and pick-up. Deliveries are supplied from a single depot at the beginning of the vehicle’s service, while pick-up loads are taken to the same depot at the conclusion of the service. Also the required time for traversing each route should not encroach the specified limit.
In this research, the aforesaid problem was introduced and a mixed integer programming model developed for it. Because of being NP-Hard and impossibility of solving it in the large instances, two...
In this research, the aforesaid problem was introduced and a mixed integer programming model developed for it. Because of being NP-Hard and impossibility of solving it in the large instances, two...
Distribution Problem in Heterogeneous Networks with the Assumption of Flexibility in the Delivery of Goods
, M.Sc. Thesis Sharif University of Technology ; Shavandi, Hasan (Supervisor)
Abstract
In this research, we consider a network of distiribution channels and a central warehouse to deliver the products to distribution centers. We assume the price of products are fixed and the central warehouse is authorized to change the delivery amount for each DC in a reasonable interval. The main idea is authorizing the central warehouse to be flexible in delivery of ordered amounts of DCs in a reasonable interval in order to reduce the transportation cost and then maximizing the profit.
The problem is formulated as a linear integer programming model and the properties of optimal solution is analyzed. Based on the properties of the model a solution algorithm is developed to solve the...
The problem is formulated as a linear integer programming model and the properties of optimal solution is analyzed. Based on the properties of the model a solution algorithm is developed to solve the...
Designing a Maritime Passenger’s Transportation Network in Persian Gulf
, M.Sc. Thesis Sharif University of Technology ; Akbari Jokar, Mohammad Reza (Supervisor)
Abstract
Persian Gulf with 21 Iranian islands and various ports from Makran’s coast in the south east of the country to Khorramshahr port in the southwest with significant potential for promotion of tourism industry and transportation of marine passengers between the coastal provinces of the country and the neighboring countries of the southern border of the Persian Gulf. The shipping of the sea includes different types of floats with different passenger capacities and strokes that the floating right selection is appropriate to the type of trip and the number of passengers which including the various costs.In summary, what we are looking for in this research are:
1.Select location or locations as...
1.Select location or locations as...
Optimization in Vehicle Routing Problem (VRP)in Servicing Customers, by Considering the Customer's Physical Location is not Fixed
, M.Sc. Thesis Sharif University of Technology ; Akbari Jokar, Mohammad Reza (Supervisor)
Abstract
Due to the expansion and development of traffic routes, expecting customers to stay at a place for a long time would rise dissatisfaction and so on in this present study we are going to consider classical vehicle routing problem with simultaneous pick-up and delivery. Vehicles are allowed to have multiple trips and to improve customer’s flexibility and improving service level, different potential locations for each customer are considered. This type of problems in the literature are called vehicle routing problem with roaming deliveries and we expand it with some strong assumption to make the problem more real.In the proposed model there is an objective function that minimizes both variable...