To see the other types of publications on this topic, follow the link: Vehicle routing and scheduling.
Dissertations / Theses on the topic 'Vehicle routing and scheduling'
Create a spot-on reference in APA, MLA, Chicago, Harvard, and other styles
Consult the top 50 dissertations / theses for your research on the topic 'Vehicle routing and scheduling.'
Next to every source in the list of references, there is an 'Add to bibliography' button. Press on it, and we will generate automatically the bibliographic reference to the chosen work in the citation style you need: APA, MLA, Harvard, Chicago, Vancouver, etc.
You can also download the full text of the academic publication as pdf and read online its abstract whenever available in the metadata.
Browse dissertations / theses on a wide variety of disciplines and organise your bibliography correctly.
1
Mu, Qianxin. "Disruption management in vehicle routing and scheduling." Thesis, Lancaster University, 2010. http://ethos.bl.uk/OrderDetails.do?uin=uk.bl.ethos.543984.
Full text
2
Arunapuram, Sundararajan. "Vehicle routing and scheduling with full loads." Case Western Reserve University School of Graduate Studies / OhioLINK, 1993. http://rave.ohiolink.edu/etdc/view?acc_num=case1056646152.
Full text
3
Eibl, Peter G. "Computerised vehicle routing and scheduling in brewery distribution." Thesis, University of South Wales, 1995. https://pure.southwales.ac.uk/en/studentthesis/computerised-vehicle-routing-and-scheduling-in-brewery-distribution(65ecb5ac-c789-4ead-a72a-2605371ca202).html.
Full textAbstract:
Over the past twenty years academics, industry commentators and practitioners in the field of physical distribution have been pre-occupied with the computational and technical side of computerised vehicle routing and scheduling (CVRS). Comparatively little research activity has been carried out on the user or management aspects of the technology. The current study aims to make up for this research deficit by investigating the adoption of CVRS technology in the British road freight industry. Moreover, the study evaluates the success of the software used in a strategic, tactical and operational role. The subject of the empirical analyses is the British brewing industry. The findings highlight the fact that CVRS technology is used by only a relatively small number of organisations despite being an effective means to improve the efficiency of transport operations and to provide substantial intangible benefits. The research also develops and empirically validates a model of CVRS in the organisational context. "Organisational context" means that the focus is on the organisational aspects rather than on the technical aspects of the technology. The model investigates relationships between variables and addresses two major research questions: What are the reasons leading to the apparent lack of CVRS system penetration - the "CVRS user-gap"? What are the key factors of successful implementations and subsequent use of the software? To overcome the "CVRS user-gap", the study suggests appropriate measures focusing on individuals' awareness of and attitudes towards the software rather than on improving the quality of the software. To ensure CVRS success, the potential users of CVRS should have a certain level of technological and organisational maturity. Emphasis needs to be placed on adequate system implementation. Special attention should also be given to three critical success factors: the quality of the software; the system operator's ability to use the software; and the drivers willingness and ability to adhere to the computer-generated route proposals.
4
Kenyon, Astrid Sandrine. "Stochastic vehicle routing problems with random travel times /." Digital version accessible at:, 1998. http://wwwlib.umi.com/cr/utexas/main.
Full text
5
Gurumurthy, Prakash. "Dynamic stochastic vehicle routing model in home healthcare scheduling /." free to MU campus, to others for purchase, 2004. http://wwwlib.umi.com/cr/mo/fullcit?p1426064.
Full text
6
Gutierrez, Bonilla Andres Felipe. "Maintenance Scheduling and Vehicle Routing Optimisation with Stochastic Components." Thesis, Troyes, 2018. http://www.theses.fr/2018TROY0023.
Full textAbstract:
Cette thèse est dédiée aux problèmes de tournées de véhicules stochastiques (SVRP) abordés dans un contexte de planification de tâches de maintenance. Le paradigme de solutions À Priori est choisi pour inclure les incertitudes au moment de la planification. Deux SVRP sont étudiés, d’abord le problème avec demandes stochastiques, qui est résolu par un algorithme mémétique (MA) hybridé avec une procédure de recherche adaptative randomisée. La méthode s’est montrée compétitive en comparaison à d’autres approches disponibles dans la littérature. Ensuite le SVRP avec fenêtre de temps sur le service, et temps de trajets et de services stochastiques est considéré. Un algorithme mémétique parallèle est conçu pour le résoudre efficacement. Un troisième problème traitant de l’ordonnancement de la maintenance pour un parc d’éoliennes est étudié dans cette thèse. D’abord une version déterministe et bi-objective est modélisée sous forme d’un programme linéaire à variables mixtes, puis résolue par une méthode de type epsilon contraintes. Une extension du problème sur un horizon de planification long et considérant les stratégies de maintenance est également proposée, et le problème est résolu par une méthode basée sur la simulation. Les méthodes développées mettent en évidence, pour les deux derniers problèmes, le conflit entre la minimisation des coûts de maintenance et la maximisation de la production énergétiqueThis thesis studies Stochastic Vehicle Routing Problems (SVRPs) in the context of maintenance tasks scheduling. Stochastic programming under an A Priori paradigm is used to incorporate the uncertainties. Two SVRPs are addressed, the first one deals with Stochastic Demands which is solved by a hybrid approach combining a memetic algorithm (MA) and a Greedy Randomized Adaptive Search Procedure (GRASP). The designed hybrid method is shown to be competitive compared to other published approaches. Second, the SVRP with stochastic travel and service times and hard time windows investigated. A parallel Memetic Algorithm is designed to solve efficiently this last problem. A third problem devoted to maintenance scheduling in wind farm context is also studied in this work. First the problem is formulated as a deterministic linear bicriteria mixed integer program, then an epsilon constraint is developed to solve it. An extension to a maintenance planning problem involving a long horizon is also addressed using a simulation approach. This last part also considers maintenance strategies selection. Both developed approaches show the existing conflicts between energy production maximization and maintenance costs minimization
7
Guo, Zigang. "Optimization of stochastic vehicle routing with soft time windows." Click to view the E-thesis via HKUTO, 2006. http://sunzi.lib.hku.hk/hkuto/record/B36758255.
Full text
8
Chen, Yujie. "Optimisation for large-scale maintenance, scheduling and vehicle routing problems." Thesis, University of York, 2017. http://etheses.whiterose.ac.uk/16107/.
Full textAbstract:
Solving real-world combinatorial problems is involved in many industry fields to minimise operational cost or to maximise profit, or both. Along with continuous growth in computing power, many asset management decision-making processes that were originally solved by hand now tend to be based on big data analysis. Larger scale problem can be solved and more detailed operation instructions can be delivered. In this thesis, we investigate models and algorithms to solve large scale Geographically Distributed asset Maintenance Problems (GDMP). Our study of the problem was motivated by our business partner, Gaist solutions Ltd., to optimise scheduling of maintenance actions for a drainage system in an urban area. The models and solution methods proposed in the thesis can be applied to many similar issues arising in other industry fields. The thesis contains three parts. We firstly built a risk driven model considering vehicle routing problems and the asset degradation information. A hyperheuristic method embedded with customised low-level heuristics is employed to solve our real-world drainage maintenance problem in Blackpool. Computational results show that our hyperheuristic approach can, within reasonable CPU time, produce much higher quality solutions than the scheduling strategy currently implemented by Blackpool council. We then attempt to develop more efficient solution approaches to tackle our GDMP. We study various hyperheuristics and propose efficient local search strategies in part II. We present computational results on standard periodic vehicle routing problem instances and our GDMP instances. Based on manifold experimental evidences, we summarise the principles of designing heuristic based solution approaches to solve combinatorial problems. Last bu not least, we investigate a related decision making problem from highway maintenance, that is again of interest to Gaist solutions Ltd. We aim to make a strategical decision to choose a cost effective method of delivering the road inspection at a national scale. We build the analysis based on the Chinese Postman Problem and theoretically proof the modelling feasibility in real-world road inspection situations. We also propose a novel graph reduction process to allow effective computation over very large data sets.
9
Bowden, Zachary E. "Behavioral Logistics and Fatigue Management in Vehicle Routing and Scheduling Problems." Diss., Virginia Tech, 2016. http://hdl.handle.net/10919/79792.
Full textAbstract:
The vehicle routing problem (VRP), is a classic optimization problem that aims to determine the optimal set of routes for a fleet of vehicles to meet the demands of a set of customers. The VRP has been studied for many decades and as such, there are many variants and extensions to the original problem. The research presented here focuses on two different types of vehicle routing and scheduling planning problems: car shipping and fatigue-aware scheduling. In addition to modeling and solving the car shipping problem, this research presents a novel way for ways in which drivers can describe their route preferences in a decision support system. This work also introduces the first fatigue-aware vehicle scheduling problem called the Truck Driver Scheduling Problem with Fatigue Management (TDSPFM). The TDSPFM is utilized to produce schedules that keep the drivers more alert than existing commercial vehicle regulations. Finally, this work analyzes the effect of the starting alertness level on driver alertness for the remainder of the work week and examines a critical shortcoming in existing regulations.Ph. D.
10
Guo, Zigang, and 郭自剛. "Optimization of stochastic vehicle routing with soft time windows." Thesis, The University of Hong Kong (Pokfulam, Hong Kong), 2006. http://hub.hku.hk/bib/B36758255.
Full text
11
Hashimoto, Hideki. "Studies on local search-based approaches for vehicle routing and scheduling problems." 京都大学 (Kyoto University), 2008. http://hdl.handle.net/2433/93466.
Full text
12
Moser, Huey D. "Scheduling and routing Tactical Aerial Reconnaissance Vehicles." Thesis, Monterey, California : Naval Postgraduate School, 1990. http://handle.dtic.mil/100.2/ADA239523.
Full textAbstract:
Thesis (M.S. in Operations Research)--Naval Postgraduate School, September 1990.Thesis Advisor(s): Rosenthal, Richard E. Second Reader: Bloch, Paul S. "September 1990." Description based on title screen as viewed on March 19, 2010. DTIC Identifier(s): Unmanned Aaerial Vehicles. Author(s) subject terms: Heuristic Programming, Traveling Salesman Problem, Routing with time windows, Unmanned Aerial Vehicle. Includes bibliographical references (p. 56-57). Also available in print.
13
Brandao, Jose Carlos Soares. "A decision support system and algorithms for the vehicle routing and scheduling problem." Thesis, Lancaster University, 1994. http://ethos.bl.uk/OrderDetails.do?uin=uk.bl.ethos.238909.
Full text
14
Wing, Michael Antony. "Artificial intelligence techniques in the scheduling and routing of automated guided vehicle systems." Thesis, Kingston University, 1990. http://eprints.kingston.ac.uk/20546/.
Full textAbstract:
This dissertation examines the problems of scheduling and routing automated guided vehicles (AGVs). AGVs are unmanned vehicles following a network of guide paths controlled by a supervisory controller. They represent a highly flexible material moving system well suited to the developing technologies of advanced manufacturing. The research in this area is motivated by the importance of AGVs in modern factories and the inadequacies of current methods of control. These inadequacies include the lack of adequate temporal reasoning, production of vehicle schedules that support automated guided vehicle system (AGVS) rather than global manufacturing objectives, the inability to produce quickest routes for vehicles and the lack of dynamic replanning. Unlike conventional controllers of AGVs the AGV scheduler presented in this dissertation (PRISMM - Planner for Reactive Intelligent Scheduling of Material Movement) considers global manufacturing objectives as well as local AGVS objectives when generating AGV schedules. It exploits novel techniques for routing vehicles that uniquely allow the integration of the shortest or the quickest routes into a timetable of vehicle movements. The techniques guarantee to find a route if one exists and will allow the imposition of deadlines. Algorithms to find a fast route through large or extremely busy route networks have also been derived. These methods will guarantee to find a route between two points as long as the vehicle begins its journey from a reserved parking space. A replanning technique has been proposed for dealing with most common errors of AGV schedule execution. A new method for the most commonly encountered problem requires no reordering of plan steps.
15
Seixas, Michel Povlovitsch. "Heuristic and exact methods applied to a rich vehicle routing and scheduling problem." Universidade de São Paulo, 2013. http://www.teses.usp.br/teses/disponiveis/3/3135/tde-09072014-111258/.
Full textAbstract:
This study considers a vehicle routing problem with time windows, accessibility restrictions on customers and a fleet that is heterogeneous with regard to capacity, average speed and cost. A vehicle can perform multiple routes per day, all starting and ending at a single depot, and it is assigned to a single driver, whose total work hours are limited. The available fleet is divided into an owned fleet, for which a variable cost is incurred, and a chartered fleet, for which only a fixed cost is incurred for each vehicle used. A column generation algorithm embedded in a branch-and-bound framework is proposed. The column generation pricing subproblem required a specific elementary shortest path problem with resource constraints algorithm to address the possibility for each vehicle performing multiple routes per day and to address the need to determine the workdays start time within the planning horizon. To make the algorithm efficient, a constructive heuristic and a learning metaheuristic algorithm based on tabu search were also developed. Both were used on branch-and-bound tree nodes to generate a good initial solution to the linear restricted master problem; particularly, to find a good initial primal bound to the branch-and-bound tree.Este estudo aborda um problema de roteirização de veículos com janelas de tempo, restrições de acessibilidade nos clientes e uma frota que é heterogênea em relação à capacidade de carga, velocidade média de deslocamento e custo. Um veículo pode percorrer múltiplas rotas por dia, todas começando e terminando em um mesmo depósito, e está designado a um único motorista, cujo total de horas trabalhadas no dia está limitado a um valor máximo. A frota disponível é dividida em uma frota própria, para a qual um custo variável é incorrido, e uma frota de freteiros, para a qual apenas um custo fixo é incorrido para cada veículo utilizado. Um algoritmo baseado em geração de colunas, integrado a um procedimento de branch-and-bound, é proposto neste estudo. O subproblema de precificação da geração de colunas requereu um algoritmo específico para o problema do caminho mínimo elementar com restrições sobre recursos capaz de lidar com a possibilidade de cada veículo percorrer múltiplas rotas por dia e capaz de lidar com a necessidade de determinar o instante de início do dia de trabalho do motorista dentro do horizonte de planejamento. Para tornar o algoritmo eficiente, uma heurística construtiva e uma heurística de melhoria baseada em busca tabu também foram desenvolvidos. Ambos são utilizados nos nós da árvore de branch-and-bound para gerar boas soluções iniciais para o problema mestre restrito da geração de colunas; particularmente, para encontrar um bom limitante primal inicial para a árvore de branch-and-bound.
16
Pillac, Victor. "Dynamic vehicle routing : solution methods and computational tools." Phd thesis, Ecole des Mines de Nantes, 2012. http://tel.archives-ouvertes.fr/tel-00742706.
Full textAbstract:
Within the wide scope of logistics management,transportation plays a central role and is a crucialactivity in both production and service industry.Among others, it allows for the timely distributionof goods and services between suppliers, productionunits, warehouses, retailers, and final customers.More specifically, Vehicle Routing Problems(VRPs) deal with the design of a set of minimal costroutes that serve the demand for goods orservices of a set of geographically spread customers,satisfying a group of operational constraints.While it was traditionally a static problem, recenttechnological advances provide organizations withthe right tools to manage their vehicle fleet in realtime. Nonetheless, these new technologies alsointroduce more complexity in fleet managementtasks, unveiling the need for decision support systemsdedicated to dynamic vehicle routing. In thiscontext, the contributions of this Ph.D. thesis arethreefold : (i) it presents a comprehensive reviewof the literature on dynamic vehicle routing ; (ii)it introduces flexible optimization frameworks thatcan cope with a wide variety of dynamic vehiclerouting problems ; (iii) it defines a new vehicle routingproblem with numerous applications.
17
Qiu, Shengli. "Airline crew pairing optimization problems and capacitated vehicle routing problems." Diss., Georgia Institute of Technology, 2012. http://hdl.handle.net/1853/51717.
Full textAbstract:
Crew pairing and vehicle routing are combinatorial optimization problems that have been studied for many years by researchers worldwide. The aim of this research work is to investigate effective methods for solving large scale crew pairing problems and vehicle routing problems. In the airline industry, to address the complex nature of crew pairing problems, we propose a duty tree method followed by a primal-dual subproblem simplex method. The duty tree approach captures the constraints that apply to crew pairings and generate candidate pairings taking advantage of various proposed strategies. A huge number of legal pairings are stored in the duty tree and can be enumerated. A set partitioning formulation is then constructed, and the problem is solved using a primal-dual subproblem simplex method tailored to the duty tree approach. Computational experiments are conducted to show the effectiveness of the methods. We also present our efforts addressing the capacitated vehicle routing problem (CVRP) that is the basic version of many other variants of the problem. We do not attempt to solve the CVRP instances that have been solved to optimality. Instead, we focus on investigating good solutions for large CVRP instances, with particular emphasis on those benchmark problems from the public online library that have not yet been solved to optimality by other researchers and determine whether we can find new best-known solutions. In this research, we propose a route network that can store a huge number of routes with all routes being legal, a set partitioning formulation that can handle many columns, and the primal-dual subproblem simplex method to find a solution. The computational results show that our proposed methods can achieve better solutions than the existing best-known solutions for some difficult instances. Upon convergence of the primal-dual subproblem simplex method on the giant-tour based networks, we use the near optimal primal and dual solution as well as solve the elementary shortest path problem with resource constraints to achieve the linear programming relaxation global optimal solution.
18
Manasanan, Titapunyapat. "A GENETIC APPROACH FOR TWO-ECHELON CAPACITATED VEHICLE ROUTING AND SCHEDULING PROBLEM WITH TIME WINDOWS." 京都大学 (Kyoto University), 2015. http://hdl.handle.net/2433/202695.
Full text
19
Qureshi, Ali Gul. "A COLUMN GENERATION BASED EXACT SOLUTION FOR VEHICLE ROUTING AND SCHEDULING PROBLEM WITH SOFT TIME WINDOWS." 京都大学 (Kyoto University), 2008. http://hdl.handle.net/2433/124490.
Full text
20
Aguayo, Bustos Maichel Miguel. "Modeling, Analysis, and Exact Algorithms for Some Biomass Logistics Supply Chain Design and Routing Problems." Diss., Virginia Tech, 2016. http://hdl.handle.net/10919/81878.
Full textAbstract:
This dissertation focuses on supply chain design and logistics problems with emphasis on biomass logistics and routing problems. In biomass logistics, we have studied problems arising in a switchgrass-based bio-ethanol supply chain encountered in the Southeast, and a corn stover harvest scheduling problem faced in the Midwest Unites States, both pertaining to the production of cellulosic ethanol. The main contributions of our work have been in introducing new problems to the literature that lie at the interface of the lot-sizing and routing problems, and in developing effective exact algorithms for their solution.
In the routing area, we have addressed extensions of the well-known traveling salesman and vehicle routing problems. We have proposed new formulations and have developed exact algorithms for the single and multiple asymmetric traveling salesmen problems (ATSP and mATP), the high-multiplicity asymmetric traveling salesman problem (HMATSP) and its extensions, and the fixed-destination multi-depot traveling salesman problem with load balancing (FD-MTSPB). Furthermore, we have introduced a new strategy to reduce routing cost in the classical vehicle routing problem (VRP).Ph. D.
21
Bhusiri, Narath. "EXACT SOLUTIONS FOR VEHICLE ROUTING AND SCHEDULING PROBLEMS WITH FULL SOFT TIME WINDOWS USING COLUMN GENERATION AND LABELING ALGORITHMS." 京都大学 (Kyoto University), 2013. http://hdl.handle.net/2433/180484.
Full text
22
Daniel, Aang. "Routing and Scheduling with Time Windows: Models and Algorithms for Tramp Sea Cargos and Rail Car-Blocks." Diss., Atlanta, Ga. : Georgia Institute of Technology, 2006. http://hdl.handle.net/1853/19698.
Full textAbstract:
Thesis (Ph.D)--Industrial and Systems Engineering, Georgia Institute of Technology, 2007.Committee Chair: Al-Khayyal, Faiz; Committee Member: Barnes, Earl; Committee Member: Johnson, Ellis; Committee Member: Karimi, IA; Committee Member: Sokol, Joel.
23
Shi, Yong. "Modeling and Solving Home Health Care Routing and Scheduling Problem with Consideration of Uncertainties." Thesis, Bourgogne Franche-Comté, 2018. http://www.theses.fr/2018UBFCA027.
Full textAbstract:
Les soins de santé à domicile (HHC) sont un large éventail de services de santé pouvant être dispensés à domicile pour une maladie ou une blessure. Ces dernières années, le secteur des soins de santé est devenu l'un des plus grands secteurs de l'économie des pays développés. L'un des défis les plus importants dans le domaine des HHC consiste à affecter plus efficacement les ressources en main-d'œuvre et les équipements sous des ressources limitées. Étant donné que le coût du transport est l’une des dépenses les plus critiques dans les activités de l’entreprise, il est très important d’optimiser le problème de routage des véhicules pour les sociétés HHC.Cependant, la majorité des travaux existants ne prennent en compte que le modèle déterministe. Dans la pratique de HHC, le décideur et les aidants rencontrent souvent des incertitudes. Il est donc essentiel d'intégrer l'incertitude dans le modèle pour établir un calendrier raisonnable pour la société HHC. Cette thèse aborde le problème du routage et de la planification HHC en prenant en compte respectivement la demande non déterministe, le service et le temps de parcours. Le corps principal de la thèse est composé de trois œuvres indépendantes.(1) Sur la base de la théorie de la crédibilité floue, nous avons proposé un modèle de programmation par contraintes de hasard flou (FCCP) pour le problème de routage HHC avec une demande floue. Ce modèle présente à la fois des caractéristiques d'optimisation combinatoire et de FCCP. Pour faire face au problème à grande échelle, nous avons développé un algorithme génétique hybride avec la simulation de Monte Carlo. Trois séries d'expériences ont été menées pour valider les performances du modèle et de l'algorithme proposés. Enfin, l’analyse de sensibilité a également porté sur l’observation du paramètre variable impliqué dans la prise de décision floue.(2) En fonction de l'activité des soignants de HHC, nous avons proposé un modèle de programmation stochastique en deux étapes avec recours (SPR) pour la livraison et la reprise simultanées avec des temps de trajet et de service stochastiques dans HHC. Pour résoudre le modèle, nous avons d’une part réduit le modèle au cas déterministe. Le solveur de Gurobi, le recuit simulé (SA), l’algorithme de chauve-souris, l’algorithme de luciole ont été proposés pour résoudre le modèle déterministe pour 56 instances respectivement. Enfin, le SA a été adopté pour traiter le modèle SPR. Une comparaison entre les solutions obtenues par les deux modèles a également été réalisée pour mettre en évidence la prise en compte des temps de parcours et de service stochastiques.(3) Pour garantir la qualité du service, sur la base d’un budget de la théorie de l’incertitude, nous avons proposé un modèle d’optimisation robuste (RO) pour HHC Routing, prenant en compte les exigences en termes de temps de déplacement et de service. La vérification de la solution réalisable a été réécrite en tant que fonction récursive complexe. Recherche tabou, SA, Recherche de voisinage variable sont également adaptés pour résoudre le modèle. Un grand nombre d'expériences ont été réalisées pour évaluer le modèle déterministe et le modèle RO. Une analyse de sensibilité des paramètres a également été effectuéeHome health care (HHC) is a wide range of healthcare services that can be given in one's home for an illness or injury. In recent years, the healthcare industry has become one of the largest sectors of the economy in developed countries. One of the most significant challenges in HHC domain is to assign the labor resources and equipment more efficiently under limited resources. Since the transportation cost is one of the most critical spendings in the company activities, it is of great significance to optimize the vehicle routing problem for HHC companies.However, a majority of the existing work only considers the deterministic model. In the practical of HHC, the decision-makers and caregivers often encounter with uncertainties. So, it is essential to incorporate the uncertainty into the model to make a reasonable and robust schedule for HHC company. This thesis addresses the HHC routing and scheduling problem with taking into account the non-deterministic demand, uncertain service and travel time respectively. The main body the thesis is composed of three independent works.(1) Based on the Fuzzy Credibility Theory, we proposed a fuzzy chance constraint programming (FCCP) model for HHC routing problem with fuzzy demand. This model has both characteristics of combinatorial optimization and FCCP. To deal with the large-scale problem, we developed a Hybrid Genetic Algorithm with the Monte Carlo simulation. Three series of experiments were conducted to validate the performance of the proposed model and algorithm. At last the sensitivity analysis was also carried out the observe the variable parameter involved in the fuzzy decision-making.(2) According to the activity of the caregivers in HHC, we proposed a two-stage stochastic programming model with recourse (SPR) for the simultaneous delivery and pick-up with stochastic travel and service times in HHC. To solve the model, firstly, we reduced the model to the deterministic one. Gurobi Solver, Simulated Annealing (SA), Bat Algorithm (BA), Firefly Algorithm (FA) were proposed to solve the deterministic model for 56 instances respectively. At last the SA was adopted to address the SPR model. Comparison between the solutions obtained by the two models was also conducted to highlight the consideration of the stochastic travel and service times.(3) To guarantee the service quality, based on a budget of uncertainty theory, we proposed a Robust Optimization (RO) model for HHC Routing with considering skill requirements under travel and service times uncertainty. The feasible solution check was rewritten as a complex recursive function. Tabu Search, SA, Variable Neighborhood Search are adapted to solve the model. A large number of experiments had been performed to evaluate the deterministic model and the RO model
24
Ta, Quang-Chieu. "Matheuristic algorithms for minimizing total tardiness in flow shop scheduling problems." Thesis, Tours, 2015. http://www.theses.fr/2015TOUR4002/document.
Full textAbstract:
Nous considérons dans cette thèse un problème d’ordonnancement de flow-shop de permutation où un ensemble de travaux doit être ordonnancé sur un ensemble de machines. Les travaux doivent être ordonnancés sur les machines dans le même ordre. L’objectif est de minimiser le retard total. Nous proposons des algorithmes heuristiques et des nouvelles matheuristiques pour ce problème. Les matheuristiques sont un nouveau type d’algorithmes approchés qui ont été proposés pour résoudre des problèmes d’optimisation combinatoire. Les méthodes importent de la résolution exacte au sein des approches (méta) heuristiques. Ce type de méthode de résolution a reçu un grand intérêt en raison de leurs très bonnes performances pour résoudre des problèmes difficiles. Nous présentons d’abord les concepts de base d’un problème d’ordonnancement. Nous donnons aussi une brève introduction à la théorie de l’ordonnancement et nous présentons un panel de méthodes de résolution. Enfin, nous considérons un problème où un flow shop de permutation à m-machine et un problème de tournées de véhicules sont intégrés, avec pour objectif la minimisation de la somme des retards. Nous proposons un codage direct d’une solution et une méthode de voisinage. Les résultats montrent que l’algorithme Tabou améliore grandement la solution initiale donnée par EDD et où chaque voyage ne délivre qu’un travailWe consider in this thesis a permutation flow shop scheduling problem where a set of jobs have to be scheduled on a set of machines. The jobs have to be processed on the machines in the same order. The objective is to minimize the total tardiness. We propose heuristic algorithms and many new matheuristic algorithms for this problem. The matheuristic methods are a new type of approximated algorithms that have been proposed for solving combinatorial optimization problems. These methods embed exact resolution into (meta)heuristic approaches. This type of resolution method has received a great interest because of their very good performances for solving some difficult problems. We present the basic concepts and components of a scheduling problem and the aspects related to these components. We also give a brief introduction to the theory of scheduling and present an overview of resolution methods. Finally, we consider a problem where m-machine permutation flow shop scheduling problem and a vehicle routing problem are integrated and the objective is to minimize the total tardiness. We introduce a direct coding for a complete solution and a Tabu search for finding a sequence and trips. The results show that the TS greatly improves the initial solution given by EDD heuristic where each trip serves only one job at a time
25
Palmer, Andrew. "The development of an integrated routing and carbon dioxide emissions model for goods vehicles." Thesis, Cranfield University, 2007. http://hdl.handle.net/1826/2547.
Full textAbstract:
The issues of global warming and climate change are a worldwide concern
and the UK government has committed itself to major reductions in CO2
emissions, the most significant of the six greenhouse gases. Road transport
currently accounts for about 22% of total UK emissions of CO2, and has been
steadily rising. Therefore, initiatives are required to try and reduce the gas
emissions in this sector.
The aim of this research has been to develop a computer based vehicle
routing model that calculates the overall amount of CO2 emitted from road
journeys, as well as time and distance. The model has been used to examine
a number of delivery strategies to assess how CO2 emissions vary. The aim
has not been to produce new mathematical theories, but to produce an
innovative basis for routing which will provide new information and knowledge
about how CO2 emissions vary for different minimisation and congestion
criteria.
The approach used in this research brings together elements from
transportation planning and environmental modelling combined with logistics
based vehicle routing techniques. The model uses a digitised road network
containing predicted traffic volumes, to which speed flow formulae are applied
so that a good representation of speed can be generated on each of the
roads. This means that the model is uniquely able to address the issue of
congestion in the context of freight vehicle routing. It uses driving cycle data to
apply variability to the generated speeds to reflect acceleration and
deceleration so that fuel consumption, and therefore CO2, can be estimated.
Integrated within the model are vehicle routing heuristics to enable routes to
be produced which minimise the specified criterion of time, distance or CO2.
The results produced by the model show that there is a potential to reduce
CO2 emissions by about 5%. However, when other transport externalities are
considered overall benefits are dependent on road traffic volumes.
26
Afroze, Tonima, and Gardell Moa Rosén. "Algorithm Construction for Efficient Scheduling of Advanced Health Care at Home." Thesis, KTH, Skolan för teknik och hälsa (STH), 2015. http://urn.kb.se/resolve?urn=urn:nbn:se:kth:diva-170392.
Full textAbstract:
Providing advanced health care at home rather than in a hospital creates a greater quality of life for patients and their families. It also lowers the risk of hospital-acquired infections and accelerates recovery. The overall cost of care per patient is decreased. Manual scheduling of patient visits by health care professionals (HCPs) has become a bottleneck for increased patient capacity at SABH, a ward providing advanced pediatric health care at home (“Sjukhusansluten Avancerad Barnsjukvård i Hemmet” in Swedish), since many parameters need to be taken into account during scheduling. This thesis aims to increase the efficiency of SABH’s daily scheduling of personnel and resources by designing an automated scheduler that constructs a daily schedule and incorporates changes in it when needed in order to remove scheduling as a limitation for increased patient capacity. Requirements on a feasible schedule are identified in cooperation with SABH and literature is investigated about similar areas where the scheduling process has been automated. The scheduling is formulated as a computerized problem and investigated from the perspective of theoretical computer science. We show that the scheduling problem is NP-hard and can therefore not be expected to be solved optimally. The algorithm for scheduling the visits minimizes violations of time windows and travel times, and maximizes person continuity and workload balancing. The algorithm constructs an initial solution that fulfills time constraints using a greedy approach and then uses local search, simulated annealing, and tabu search to iteratively improve the solution. We present an exact rescheduling algorithm that incorporates additional visits after the original schedule has been set. The scheduling algorithm was implemented and tested on real data from SABH. Although we found the algorithm to be efficient, automatic transfer of data from the patient journal system is an imperative for the scheduler to be adopted.Barn som får avancerad sjukvård hemma istället för på sjukhus tillfrisknar ofta snabbare och risken för vårdrelaterade infektioner minskar. Barnen och deras familjer blir mer välmående av att få vistas i sin hemmiljö. På Astrid Lingrens barnsjukhus i Stockholm erbjuds avancerad hemsjukvård av avdelningen Sjukhusansluten Avancerad Barnsjukvård i Hemmet (SABH). För att schemalägga när patienterna ska besökas av sjukvårdspersonalen behöver många olika faktorer beaktas, detta sker idag helt manuellt. Den manuella schemaläggningen utgör en naturlig begränsning av SABHs patientkapacitet. Denna uppsats syftar till att effektivisera schemaläggningsprocessen hos SABH genom att föreslå en automatiserad lösning som hanterar koordinering av personal och resurser och dem förändringar som behöver göras i schemat under dagen, för att få bort schemaläggningsprocessen som ett hinder mot ökad patientkapacitet. Krav på schemaläggningen identifieras i diskussion med SABH och genom att studera litteratur kring liknande områden där schemaläggning lösts automatiserat. Vi formulerar schemaläggningen som ett datologiskt problem och analyserar det med utgångspunkt i teoretisk datalogi. Vi visar att problemet är NP-svårt och därför inte kan förväntas lösas optimalt inom rimlig tid. Vår lösning approximerar istället fram ett rimligt svar, där fokus hos algoritmen är att patienterna ska besökas de tider de behöver, personalens restider ska vara så korta som möjligt samtidigt som arbetsbördan hos personalen ska vara så lika fördelad som möjligt och patienterna ska, i den mån det är möjligt, få vård av samma personal. Med en girig algoritm konstrueras ett initialt schema som uppfyller de grundläggande kraven, detta schema förbättras med lokalsökning, simulated annealing och tabusökning. En exakt lösning framställs för uppdatering av schemat. Algoritmen för att lägga ett dagligt schema (utan uppdateringar) implementerades och testades med riktigt data från SABH. Vår algoritm visade sig vara effektiv, men för att kunna göra hela schemaläggningsprocessen effektiv behöver den integreras med journalsystemet.
27
Goel, Asvin. "Legal aspects in road transport optimization in Europe." Elsevier, 2018. https://publish.fid-move.qucosa.de/id/qucosa%3A72189.
Full textAbstract:
Road freight transportation is subject to several legal requirements having direct impact on the practical applicability of routes and schedules. The vast majority of vehicle routing literature, so far, has largely focused on physical constraints such as capacity limits, or customer requirements such as time windows for pickups and deliveries. This paper studies legal requirements for long-distance haulage in the European Union, identifies some major gaps in the current state-of-the-art in vehicle routing, presents approaches for overcoming this gap, and analyzes the impact of the legal requirements studied.
28
Sucupira, Igor Ribeiro. "Um Estudo Empírico de Hiper-Heurísticas." Universidade de São Paulo, 2007. http://www.teses.usp.br/teses/disponiveis/45/45134/tde-15012008-001809/.
Full textAbstract:
Uma hiper-heurística é uma heurística que pode ser utilizada para lidar com qualquer problema de otimização, desde que a ela sejam fornecidos alguns parâmetros, como estruturas e abstrações, relacionados ao problema considerado. As hiper-heurísticas têm sido aplicadas a alguns problemas práticos e apresentadas como métodos de grande potencial, no que diz respeito à capacidade de possibilitar o desenvolvimento, em tempo bastante reduzido, de algoritmos capazes de lidar satisfatoriamente, do ponto de vista prático, com problemas de otimização complexos e pouco conhecidos. No entanto, é difícil situar as hiper-heurísticas em algum nível de qualidade e avaliar a robustez dessas abordagens caso não as apliquemos a problemas para os quais existam diversas instâncias disponíveis publicamente e já experimentadas por algoritmos relevantes. Este trabalho procura dar alguns passos importantes rumo a essas avaliações, além de ampliar o conjunto das hiper-heurísticas, compreender o impacto de algumas alternativas naturais de desenvolvimento e estabelecer comparações entre os resultados obtidos por diferentes métodos, o que ainda nos permite confrontar as duas diferentes classes de hiper-heurísticas que identificamos. Com essas finalidades em mente, desenvolvemos 3 novas hiper-heurísticas e implementamos 2 das hiper-heurísticas mais importantes criadas por outros autores. Para estas últimas, experimentamos ainda algumas extensões e modificações. Os dois métodos hiper-heurísticos selecionados podem ser vistos como respectivos representantes de duas classes distintas, que aparentemente englobam todas as hiper-heurísticas já desenvolvidas e nos permitem denominar cada um desses métodos como \"hiper-heurística de busca direta por entornos\" ou como \"hiper-heurística evolutiva indireta\". Implementamos cada hiper-heurística como uma biblioteca (em linguagem C), de forma a evidenciar e estimular a independência entre o nível em que se encontra a hiper-heurística e aquele onde se apresentam as estruturas e abstrações diretamente relacionadas ao problema considerado. Naturalmente, essa separação é de ingente importância para possibilitar a reutilização imediata das hiper-heurísticas e garantir que nelas haja total ausência de informações relativas a um problema de otimização específico.A hyperheuristic is a heuristic that can be used to handle any optimization problem, provided that the algorithm is fed with some parameters, as structures and abstractions, related to the problem at hand. Hyperheuristics have been applied to some practical problems and presented as methods with great potential to allow the quick development of algorithms that are able to successfully deal, from a practical standpoint, with complex ill-known optimization problems. However, it\'s difficult to position hyperheuristics at some quality level and evaluate their robustness without applying them to problems for which there are many instances available in the public domain and already attacked by worthy algorithms. This work aims to give some important steps towards that process of evaluation, additionally increasing the number of available hyperheuristics, studying the impact of some natural development alternatives and comparing the results obtained by different methods, what also enables us to confront the two classes of hyperheuristics that we have identified. With those purposes in mind, we have developed 3 original hyperheuristics and implemented 2 of the most important hyperheuristics created by other authors. For those latter two approaches, we have also experimented with some modifications and extensions. The two methods we have chosen for implementation may be seen as respectively representing two distinct classes, which seem to contain all hyperheuristics developed so far and that allow us to classify any of these methods as either being a \"direct neighbourhood search hyperheuristic\" or an \"indirect evolutive hyperheuristic\". We have implemented each hyperheuristic as a library (in the C language), so as to clearly show and estimulate the independence between the level where the hyperheuristic is and that to which the structures and abstractions directly related to the problem at hand belong. Obviously, this separation of concerns is extremely important to make the immediate reuse of hyperheuristics possible and enforce in them the complete absence of information from a specific optimization problem.
29
Barbosa, Juliana Maria Rangel. "Aplicação de uma abordagem adaptativa de busca tabu a problemas de roteirização e programação de veículos." Universidade Federal de São Carlos, 2005. https://repositorio.ufscar.br/handle/ufscar/3799.
Full textAbstract:
Made available in DSpace on 2016-06-02T19:52:13Z (GMT). No. of bitstreams: 1
DissJMRB.pdf: 944400 bytes, checksum: b37a0f175baab577681e6785f305edee (MD5)
Previous issue date: 2005-06-23This project consists in the refinement of the tabu search adaptive approach HTSA (PUREZA, 1996) and the analysis of its performance when applied to the classical Vehicle Routing Problem and to the Vehicle Routing Problem with Time Windows. HTSA promotes the integration of intensification and diversification strategies through the systematic variation of the values of selected tabu parameters, mostly based on the analysis of search trajectory patterns. The development of new implementations based on tabu search (GLOVER, 1989; GLOVER & LAGUNA, 1997) is an interesting avenue of research since tabu search has offered new marks on solution quality in routing problems, usually outperforming other methods. The results obtained with the application of HTSA approach to a set of classical routing instances and to a set of routing with times windows instances indicate quality solutions within reasonable computational times when compared to the results provided by competitive methods in the literature.
O corrente projeto tem como objetivo o refinamento da abordagem adaptativa de busca tabu HTSA (PUREZA, 1996) e a verificação de seu desempenho quando aplicada ao Problema de Roteirização de Veículos clássico e ao Problema de Roteirização com Janelas de Tempo. A abordagem HTSA tem como objetivo a integração de estratégias de intensificação e diversificação, consistindo na variação sistemática de valores de parâmetros tabu selecionados e apoiada principalmente na análise de padrões da trajetória da busca. O desenvolvimento de novas abordagens baseadas na meta-heurística busca tabu (GLOVER, 1989; GLOVER & LAGUNA, 1997) é uma linha de pesquisa interessante uma vez que a busca tabu tem oferecido novas marcas em qualidade da solução em problemas de Roteirização de veículos e suas variantes, geralmente superando outros métodos. Os resultados obtidos com a aplicação da abordagem HTSA a instâncias de roteirização de veículos clássicas e com janela de tempo indicam soluções de qualidade em tempos computacionais razoáveis quando comparadas aos resultados de métodos competitivos da literatura.
30
Williams, Matthew J. "A Heuristic Solution to the Pickup and Delivery Problem with Applications to the Outsized Cargo Market." Ohio University / OhioLINK, 2009. http://rave.ohiolink.edu/etdc/view?acc_num=ohiou1238514369.
Full text
31
Namboothiri, Rajeev. "Planning Container Drayage Operations at Congested Seaports." Diss., Georgia Institute of Technology, 2006. http://hdl.handle.net/1853/11482.
Full textAbstract:
This dissertation considers daily operations management for a fleet of trucks providing container pickup and delivery service to a port. Truck congestion at access points for ports may lead to serious inefficiencies in drayage operations, and the resultant cost impact to the intermodal supply chain can be significant. Recognizing that port congestion is likely to continue to be a major problem for drayage operations given the growing volume of international containerized trade, this research seeks to develop optimization approaches for maximizing the productivity of drayage firms operating at congested seaports. Specifically, this dissertation addresses two daily drayage routing and scheduling problems.
In the first half of this dissertation, we study the problem of managing a fleet of trucks providing container pickup and delivery service to a port facility that experiences different access wait
times depending on the time of day. For this research, we assume that the wait time can be estimated by a deterministic function. We develop a time-constrained routing and scheduling model for the problem that incorporates the time-dependent congestion delay function. The model objective is to find routes and schedules for drayage vehicles with minimum total travel time, including the waiting time at the entry to the port due to congestion. We consider both exact and heuristic solution approaches for this difficult optimization problem. Finally, we use the framework to develop an understanding of the potential impact of congestion delays on drayage operations, and the value of planning with accurate delay information.
In the second half of this dissertation, we study methods for managing a drayage fleet serving a port with an appointment-based access control system. Responding to growing access congestion and its resultant impacts, many U.S. port terminals have implemented appointment systems, but little is known about the impact of such systems on drayage productivity. To address this knowledge gap, we
develop a drayage operations optimization approach based on a column generation integer programming heuristic that explicitly models a time-slot port access control system. The approach determines pickup and delivery sequences with minimum transportation cost. We use the framework to develop an understanding of the potential efficiency impacts of access appointment systems on drayage operations. Findings indicate that the set of feasible drayage tasks and the fleet size required to complete them can be quite sensitive to small changes in time-slot access capacities at the port.
32
Mendes, André Bergsten. "Programação de frota de apoio a operações \'offshore\' sujeita à requisição de múltiplas embarcações para uma mesma tarefa." Universidade de São Paulo, 2007. http://www.teses.usp.br/teses/disponiveis/3/3135/tde-14012008-171216/.
Full textAbstract:
A presente pesquisa aborda um problema de roteirização e programação de veículos incorporando uma nova restrição operacional: a requisição simultânea de múltiplos veículos para atendimento da demanda. Trata-se de uma característica encontrada em operações de apoio à exploração de petróleo \"offshore\", em que mais de uma embarcação é requerida para executar tarefas de reboque e lançamento de linhas de ancoragem. Esta imposição, somada às restrições de janela de tempo, precedência entre tarefas, autonomia das embarcações e atendimento integral da demanda, configuram este problema. A programação é orientada pela minimização dos custos variáveis da operação e dos custos associados ao nível de serviço no atendimento. Este problema é uma variação do problema clássico de roteirização e programação de veículos com janela de tempo, de classe NP-Difícil. Nesta pesquisa, propõe-se modelar e resolver o problema em escala real por meio do algoritmo \"branch and cut\" acoplado às heurísticas de busca em vizinhança \"local branching\" e \"variable neighborhood search\". Para gerar as soluções iniciais será empregado o método \"feasibility pump\" e uma heurística construtiva.This research focuses a fleet scheduling problem with new operational constraints: each task requiring multiple types of vehicles simultaneously. This kind of operation occurs in offshore exploitation and production sites, when more than one vessel is needed to accomplish the tugging and mooring of oil platforms. Other constraints are maintained such as time windows, precedence between tasks, route duration and the demand attendance. The solution schedules are cost oriented, which encompasses the routing variable costs and the customer service costs. This is a variation of the classical fleet routing and scheduling, which is an NP-Hard problem. This research aims to solve the real scale problem through a combined use of branch and cut strategy with local search algorithms such as local branching and variable neighborhood search. An efficient heuristic rule will be used in order to generate initial solutions using the feasibility pump method.
33
Gamba, Giorgia. "Modellazione di un sistema dinamico di order picking e material handling gestito da unmanned aerial vehicles." Master's thesis, Alma Mater Studiorum - Università di Bologna, 2017.
Find full textAbstract:
Il settore logistico sta attraversando un periodo di transizione: lo sviluppo dell’e-commerce e la mancanza di manodopera di alto livello sono i principali fattori che spingono le imprese a orientarsi verso l’automazione della logistica, pilastro di Industria 4.0. In uno scenario evoluto, dove i dettami della Lean Production sono sempre più seguiti, la movimentazione veloce e flessibile di merce inter e intra reparto si prospetta la sfida per gli anni a venire. Gli Unmanned Aerial Vehicles rappresentano, oggi, una delle soluzioni più interessanti per il settore logistico, tanto da essere ritenuti main actor del business futuro. Questo studio si inserisce perfettamente nello scenario delineato e fornisce una possibile soluzione al problema relativo all’automatizzazione dei tradizionali sistemi manuali di order picking. Lo scopo consiste nel progettare un modello dinamico di order picking e material handling gestito esclusivamente da UAV. Particolare attenzione è rivolta all’algoritmo di dispatching dei velivoli, fondamentale al fine di trasformare gli ordini in arrivo al sistema in un task schedule.
L’elaborato si apre con una breve panoramica del settore logistico e di come la robotica ne guidi lo sviluppo. A seguire, si inquadrano il problema ed i principali obiettivi. Terminata la revisione della letteratura inerente i due macro-temi trattati, droni e sistemi di picking, si entra nel vivo dell’elaborato. Il processo di costruzione del modello si articola in fasi consecutive: definizione degli input, realizzazione del modello concettuale e codifica di quest’ultimo in linguaggio di programmazione MATLAB sono i prerequisiti per procedere all’esecuzione di run simulativi, responsabili, non solo di testare la validità del modello, ma anche, di determinarne le performance. Conclude la tesi la fase di analisi degli output, significativo punto di partenza per futuri sviluppi del modello progettato.
34
Thorpe, J. C. "Vehicle scheduling." Thesis, University of Manchester, 1992. http://ethos.bl.uk/OrderDetails.do?uin=uk.bl.ethos.488397.
Full text
35
Rodrigues, Vinícius Picanço. "Uma abordagem de otimização para a roteirização e programação de navios: um estudo de caso na indústria petrolífera." Universidade Federal de São Carlos, 2014. https://repositorio.ufscar.br/handle/ufscar/3761.
Full textAbstract:
Made available in DSpace on 2016-06-02T19:52:05Z (GMT). No. of bitstreams: 1
6045.pdf: 14667118 bytes, checksum: f13a2c0983ea271f2e60ed298b158806 (MD5)
Previous issue date: 2014-05-26Agência Nacional de Petróleo
This work studies the ship routing and scheduling problem in oil transportation from offshore platforms to inland terminals. It is motivated by a real situation in a Brazilian oil company. Brazil is one of the world's greatest oil producers and has around 80% of its oil explored in offshore mode. Thus, transportation costs play an important role in achieving operational excellence, and the recent growth trends for oil exploration in Brazil has transformed its operations and demanded agile and effective decision support systems for addressing the oil sector dynamism. This work's goal consists in developing and applying an optimization-based approach using a mixed integer linear programming model in real decision-making situations, along with a solution method based on mathematical programming (MIP-heuristics) in order to solve the model, such as relax-and-fix. The proposed model is inspired in a problem formulation for pickup and delivery with time windows (PDPTW) and heterogeneous fleet, where costs incurred for fuel consumption and fleet contracts is the objective function to be minimized. The pickup and delivery pairs are predetermined and the model's main decision refers to ship allocation to these pairs compounding a route. Furthermore, some additional constraints are modeled and proposed, such as terminal access and platform mooring limitation according to ship types, as well as product blend incompatibility. The model was implemented in a modeling language along with an optimizarion software. Computational experiments with the model and the heuristics are presented for different data sets supplied by the case study company. These experiments show the potential benefits of this approach for finding good solutions for the problem as well as the dificulty in finding solutions for realistic instances due to its NP-hard characteristics.
Este trabalho estuda o problema de roteirização e programação de navios que realizam o escoamento de petróleo das plataformas marítimas para terminais terrestres, motivado por uma situação real de uma empresa brasileira da indústria petrolífera. O Brasil é um dos maiores produtores mundiais de petróleo, e cerca de 80% de seu petróleo é explorado no mar. Dentro deste contexto, os custos de transporte desempenham um papel importante na busca pela excelência operacional e as tendências de crescimento da exploração de petróleo no Brasil têm tornado as operações mais complexas e demandantes de sistemas de apoio à decisão ágeis e eficazes que contemplem o dinamismo do setor petrolífero. O objetivo deste trabalho consiste em desenvolver e aplicar uma abordagem de otimização baseada em um modelo de programação linear inteira mista em situações reais de tomada de decisão, em conjunto com métodos de solução baseados em programação matemática (MIP-Heuristics) para resolver o modelo, como relax-and-fix. O modelo proposto é inspirado em uma formulação de problemas de coleta e entrega com janelas de tempo (pickup and delivery with time windows PDPTW) e frota heterogênea, no qual busca-se minimizar os custos decorrentes do consumo de combustível dos navios e contratos de afretamento. O modelo é do tipo origem-destino, no qual os pares coleta/entrega são pré-determinados e a decisão do modelo refere-se à alocação de navios para os diferentes pares, compondo uma rota. Além disso, são propostas restrições adicionais que contemplam limitações de acesso a terminais e de atracação em plataformas de acordo com os tipos de navio, além da incompatibilidade de mistura de produtos, entre outros. O modelo foi implementado utilizando uma linguagem de modelagem em conjunto com um software de otimização. Experimentos computacionais com o modelo e as heurísticas são apresentados para diferentes conjuntos de dados fornecidos pela empresa e comprovam o potencial das abordagens para encontrar boas soluções para o problema, mas também suas dificuldades para encontrar soluções para exemplares de tamanho realista, por tratar-se de um problema NP-difícil do ponto de vista de teoria de complexidade.
36
Zhang, Xinglong. "Network vehicle routing problems." Diss., Georgia Institute of Technology, 1998. http://hdl.handle.net/1853/21710.
Full text
37
Jézéquel, Antoine. "Probabilistic vehicle routing problems." Thesis, Massachusetts Institute of Technology, 1985. http://hdl.handle.net/1721.1/15318.
Full textAbstract:
Thesis (M.S.)--Massachusetts Institute of Technology, Dept. of Civil Engineering, 1985.MICROFICHE COPY AVAILABLE IN ARCHIVES AND ENGINEERING.
Bibliography: leaves 78-79.
by Antoine Jézéquel.
M.S.
38
Mourgaya, Virapatrin Magalie. "The periodic vehicle routing problem : planning before routing." Bordeaux 1, 2004. http://www.theses.fr/2004BOR12843.
Full textAbstract:
Le problème de tournées de véhicules multipériodiques consisté à planifier des visites client sur un horizon de temps donné en les affectant à des tournées de véhicule. Les fréquences de visites ou espacement entre elles sont prescrits. Ces contraintes peuvent prendre la forme de scénarios de visites admissibles. Nous étudions les différentes variantes de ce problème et proposons une classification. Nous présentons ensuite un algorithme heuristique pour un modèle de planification tactique qui optimise la répartition de la charge et la régionalisation des tournées. L'objectif traditionnel de minimisation des distances parcourues est reporté au niveau des décisions opérationnelles. Cette approche nous a permis d'obtenir des solutions pratiques pour un problème industriel avec 16658 visites à planifier sur un horizon de 20 jours. Nous proposons enfin un heuristique d'arrondi basé sur la méthode de génération de colonnes. Cette méthode basée sur l'optimisation globale permet d'obtenir des solutions de meilleure qualité pour les problèmes de planification à court terme avec de l'ordre de 50 clients.
39
Sheasby, Janice. "Lagrangean heuristics for vehicle routing." Thesis, Coventry University, 1996. http://ethos.bl.uk/OrderDetails.do?uin=uk.bl.ethos.320251.
Full text
40
Hung, Hing-fai Daniel, and 孔慶輝. "Vehicle routing for heterogeneous fleet." Thesis, The University of Hong Kong (Pokfulam, Hong Kong), 1992. http://hub.hku.hk/bib/B31210326.
Full text
41
Hung, Hing-fai Daniel. "Vehicle routing for heterogeneous fleet." [Hong Kong : University of Hong Kong], 1992. http://sunzi.lib.hku.hk/hkuto/record.jsp?B1332701X.
Full text
42
Cattaruzza, Diego. "Vehicle Routing for City Logistics." Thesis, Saint-Etienne, EMSE, 2014. http://www.theses.fr/2014EMSE0737/document.
Full textAbstract:
Le transport de marchandises dans les zones urbaines est un sujet important de nos jours. Le transport est une activité vitale pour les villes, mais implique pollution, congestion, accidents. La logistique urbaine vise à optimiser les processus logistiques et de transports urbains en tenant compte des aspects environnementaux et sociaux. Cette thèse traite de cette thématique et fait partie du projet MODUM.MODUM vise à étudier un système de livraison basé sur des centres de distribution urbains. Nous présentons une classification et une analyse des mouvements de marchandises et des problèmes de tournées de véhicules (VRP) associés.La deuxième partie propose une revue complète des travaux de recherche traitant des problème VRP avec excursions multiples (MTVRP). Le MTVRP est une extension du VRP où les véhicules sont autorisés à effectuer plusieurs tournées. Nous proposons une heuristique pour le MTVRP qui est par la suite adaptée pour un problème plus riche, le MTVRP avec fenêtres de temps et dates de disponibilité. Il s'agit d'une variante du MTVRP où à chaque client est associée une fenêtre de temps et à chaque marchandise une date de disponibilité qui représente l'instant où elle devient disponible au dépôt.Par la suite, nous étudions une variante du MTVRP où les marchandises sont classées par types de produits qui ne peuvent pas être transportés dans le même véhicule. Une analyse est effectuée pour montrer l’avantage des tournées multiples pour le problème de dimensionnement des flottes.Enfin, nous décrivons le problème de tournées qui se pose dans MODUM et le simulateur qui est développé pour évaluation du systèmeTransportation of merchandise in urban areas has become an important nowadays topic. In fact, transportation is a vital activity for each city, but entail pollution, congestion, accidents.City logistics aims at optimizing the whole urban logistics and transportation process, taking into account environmental and social aspects. This thesis, that is part of the MODUM project, finds its location in this area of research. In particular, MODUM aims at studying a delivery system based on City Distribution Centers.We first present a classification and an analysis of urban good movements and routing problems peculiar to metropolitan areas. A second survey proposes a complete collection of articles that has been done on the Multi Trip Vehicle Routing Problem (MTVRP). The MTVRP is an extension of the Vehicle Routing Problem (VRP) where vehicles are allowed to perform several trips.We propose an efficient heuristic for the MTVRP that is, in a subsequent step, adapted to a new routing problem, the MTVRP with Time Windows and Release Dates (MTVRPTWR). It is a variant of the MTVRP where each customer is associated with a time window and each merchandise is associated with a release date that represents the instant it becomes available at the depot.We, then, study a variant of the MTVRP where goods belong to different commodities that cannot be transported at the same time by the same vehicle. An analysis is conducted on the benefits of the multi-trip aspect in fleet dimensioning problems.Finally we describe the complex routing problem that arises in MODUM and the simulator that is developed to evaluate the performances of the system
43
Villegas, Juan Guillermo. "Vehicle routing problems with trailers." Troyes, 2010. http://www.theses.fr/2010TROY0027.
Full textAbstract:
Les problèmes de tournées de véhicules forment une classe de problèmes d’optimisation combinatoire avec des applications dans de nombreux domaines comme la distribution de marchandises et l’exécution de services. Cette thèse en trois parties étudie des problèmes de tournées où la capacité des véhicules peut être augmentée par des remorques détachables. La première partie est consacrée à un problème noté STTRPSD, dans lequel un camion avec une remorque détachable doit visiter à partir d’un dépôt des clients accessibles par le camion sans sa remorque. La remorque doit donc être laissée temporairement sur certains nœuds du réseau. Pour ce problème, nous avons développé trois heuristiques, deux métaheuristiques de type GRASP et recherche locale évolutionnaire, et une méthode exacte de type branchement et coupes. La deuxième partie traite un problème nommé TTRP, qui étend le STTRPSD à plusieurs véhicules hétérogènes et à des clients accessibles ou non avec les remorques. Pour le résoudre, nous avons conçu deux méthodes : (i) une métaheuristique hybride combinant un GRASP, une recherche à voisinage variable et un « path relinking » ; et (ii) une matheuristique qui utilise les optimal locaux produits par un GRASP/VNS pour résoudre un problème de partitionnement à l’aide d’un solveur commercial. Enfin, la troisième partie présente une librairie orientée objet pour le prototypage rapide de méthodes heuristiques basées sur le principe « route-first, cluster-second ». Cette librairie fournit des composants logiciels réutilisables qui peuvent être adaptés pour gérer différentes extensionsVehicle routing problems (VRPs) are a class of combinatorial optimization problems with application in many different domains ranging from the distribution of goods to the delivery of ser-vices. In this thesis we have studied VRPs in which the capacity of the vehicles is increased with the use of detachable trailers. This thesis comprises three parts. The first part is devoted to the single truck and trailer routing problem with satellite depots (STTRPSD), where a single truck with a detach-able trailer based at a depot serves the demand of a set of customers accessible only by truck. For this problem we have developed three heuristics, two metaheuristics based on GRASP and evolutionary local search, and an exact branch-and-cut algorithm. The second part addresses the truck and trailer routing problem (TTRP) that models the multi-vehicle case, where a heterogeneous fixed fleet of trucks and trailers is used to serve the demand of a set of customers, some of them with accessibility restrictions. To solve the TTRP we have developed two methods: (i) a hybrid metaheuristic combining GRASP, variable neighborhood search (VNS) and path relinking; and (ii) a matheuristic that uses the routes of the local optima produced by a GRASP/VNS to solve a set-partitioning formulation of the TTRP with a commercial optimizer. Finally, the third part presents an object-oriented framework for the rapid prototyping of heuristic methods based on the route-first, cluster-second principle. This framework provides a set of reusable components that can be adapted to tackle different VRP extensions
44
Pereira, Victor Caon. "Vehicle Routing for Emergency Evacuations." Diss., Virginia Tech, 2013. http://hdl.handle.net/10919/52361.
Full textAbstract:
This dissertation introduces and analyzes the Bus Evacuation Problem (BEP), a unique Vehicle Routing Problem motivated both by its humanitarian significance and by the routing and scheduling challenges of planning transit-based, regional evacuations. First, a variant where evacuees arrive at constant, location-specific rates is introduced. In this problem, a fleet of capacitated buses must transport all evacuees to a depot/shelter such that the last scheduled pick-up and the end of the evacuee arrival process occurs at a location-specific time. The problem seeks to minimize their accumulated waiting time, restricts the number of pick-ups on each location, and exploits efficiencies from service choice and from allowing buses to unload evacuees at the depot multiple times. It is shown that, depending on the problem instance, increasing the maximum number of pick-ups allowed may reduce both the fleet size requirement and the evacuee waiting time, and that, past a certain threshold, there exist a range of values that guarantees an efficient usage of the available fleet and equitable reductions in waiting time across pick-up locations. Second, an extension of the Ritter (1967) Relaxation Algorithm, which explores the inherent structure of problems with complicating variables and constraints, such as the aforementioned BEP variant, is presented. The modified algorithm allows problems with linear, integer, or mixed-integer subproblems and with linear or quadratic objective functions to be solved to optimality. Empirical studies demonstrate the algorithm viability to solve large optimization problems. Finally, a two-stage stochastic formulation for the BEP is presented. Such variant assumes that all evacuees are at the pick-up locations at the onset of the evacuation, that the set of possible demands is provided, and, more importantly, that the actual demands become known once buses visit the pick-up locations for the first time. The effect of exploratory visits (sampling) and symmetry is explored, and the resulting insights used to develop an improved formulation for the problem. An iterative (dynamic) solution algorithm is proposed.Ph. D.
45
Andrews, Matthew. "Scheduling techniques for packet routing, load, balancing and disk scheduling." Thesis, Massachusetts Institute of Technology, 1997. http://hdl.handle.net/1721.1/42692.
Full text
46
Schwarz, Cornelius [Verfasser]. "Integrated Routing & Scheduling / Cornelius Schwarz." München : Verlag Dr. Hut, 2012. http://d-nb.info/1020299231/34.
Full text
47
Lücking, Thomas. "Analyzing models for scheduling and routing." [S.l. : s.n.], 2005. http://deposit.ddb.de/cgi-bin/dokserv?idn=976817896.
Full text
48
Chaundy, Duncan John Forfar Carleton University Dissertation Computer Science. "Rural school bus routing and scheduling." Ottawa, 1990.
Find full text
49
Wagner, Michael R. (Michael Robert) 1978. "Online optimization in routing and scheduling." Thesis, Massachusetts Institute of Technology, 2006. http://hdl.handle.net/1721.1/36225.
Full textAbstract:
Thesis (Ph. D.)--Massachusetts Institute of Technology, Sloan School of Management, Operations Research Center, 2006.Includes bibliographical references (leaves 169-176).
In this thesis we study online optimization problems in routing and scheduling. An online problem is one where the problem instance is revealed incrementally. Decisions can (and sometimes must) be made before all information is available. We design and analyze (polynomial-time) online algorithms for a variety of problems. We utilize worst-case competitive ratio (and relaxations thereof), asymptotic and Monte Carlo simulation analyses in our study of these algorithms. The focus of this thesis is on online routing problems in arbitrary metric spaces. We begin our study with online versions of the Traveling Salesman Problem (TSP) and the Traveling Repairman Problem (TRP). We then generalize these basic problems to allow for precedence constraints, capacity constraints and multiple vehicles. We give the first competitive ratio results for many new online routing problems. We then consider resource augmentation, where we give the online algorithm additional resources: faster servers, larger capacities, more servers, less restrictive constraints and advanced information. We derive new worst-case bounds that are relaxations of the competitive ratio.
(cont.) We also study the (stochastic) asymptotic properties of these algorithms - introducing stochastic structure to the problem data, unknown and unused by the online algorithm. In a variety of situations we show that many online routing algorithms are (quickly) asymptotically optimal, almost surely, and we characterize the rates of convergence. We also study classic machine sequencing problems in an online setting. Specifically, we look at deterministic and randomized algorithms for the problems of scheduling jobs with release dates on single and parallel machines, with and without preemption, to minimize the sum of weighted completion times. We derive improved competitive ratio bounds and we show that many well-known machine scheduling algorithms are almost surely asymptotically optimal under general stochastic assumptions. For both routing and sequencing problems, we complement these theoretical derivations with Monte Carlo simulation results.
by Michael Robert Wagner.
Ph.D.
50
Rincon, Garcia Nicolas. "Freight transport, routing software and time-dependent vehicle routing models." Thesis, University of Southampton, 2016. https://eprints.soton.ac.uk/397141/.
Full textAbstract:
Routing and scheduling software is part of the Information and Technology systems available to support the transport industry, and uses complex algorithms along with geographical representations of the road network to allow better planning of daily collection and delivery schedules. This research reviews the evolution of routing and scheduling software, the algorithms used along with reported barriers to wider take-up and potential industry driven improvements that could be made. A survey of transport companies in the United Kingdom was conducted in order to validate and prioritize the software capabilities that require the most development according to the new challenges that the industry is facing. Responses suggested that companies required improved route optimization to tackle congestion based on time-dependent data and models, and greater accuracy in the representation of the road network. Not considering congestion leads to the underestimation of travel times and the production of inaccurate schedules. Literature shows that operational research techniques are available to solve problems that represent real world conditions, but research into the relative merits of using time-dependent models needs to be undertaken. Although exact methods have been developed to solve the Vehicle Routing Problem, they cannot cope with large instances and rich variants that are required by the industry. Therefore, metaheuristic algorithms are usually implemented in routing software. A reported barrier in metaheuristic algorithms is the lack of accuracy (the difference between optimal or best-known values and the result of the proposed algorithm). In this research an algorithm was developed using elements of Large Neighbourhood Search that is capable to substantially improve the state of the art for the time-dependent Vehicle Routing Problem. Comparison of results with available test instances shows that the proposed algorithm is capable of obtaining a reduction in the number of vehicles (4.15%), travel distance (10.88%) and travel time (12.00%) compared to previous implementations in reasonable time. A variant that considers the Rules on Drivers’ hours required in the scheduling of vehicles over 3.5 tons in the European Union and the UK is also introduced. Analysis of results show result improvements in number of vehicles (19.0%), travel distance (17.7%) and route duration (4.4%) compared to previous implementations.