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  • About
  • The Global ETD Search service is a free service for researchers to find electronic theses and dissertations. This service is provided by the Networked Digital Library of Theses and Dissertations.
    Our metadata is collected from universities around the world. If you manage a university/consortium/country archive and want to be added, details can be found on the NDLTD website.
61

Optimalizace distribuce velkoobchodního podniku / Optimalization of distribution of a wholesale business company

Breburda, Tomáš January 2017 (has links)
Revision of pre-optimalization state and proposal of possible changes with a focus on lowering the transportation costs, optimizing the routing and also the service level provided to the customers. Optimalization done on several levels, on strategical and on operative level. All this achieved with combination of outputs from a routing software and using intuitive methods. Outcome to be accounted in costs per annum. Based on conditions and demands stated by the logistics manager in the contrary to customers demands, a strategy of warehouse allocation was created. Based on this information a distribution model regarding also the routing issue was created as well.
62

Prise en compte d'objectifs de stabilité pour l'organisation de collectes de déchets / Taking into account the objectives of stability for the organization of waste collection

Baniel, Frédérique 12 November 2009 (has links)
L'étude menée dans cette thèse porte sur la logistique multi-objectif des déchets ménagers. Elle s'est déroulée en partenariat avec une collectivité locale, la Communauté d'Agglomération du Muretain (CAM) située près de Toulouse qui nous a fournit les problématiques et les différents paramètres à prendre en compte pour le développement de l'étude. Cette thèse s'est déroulée au sein de deux équipes, dans l'équipe de Production Automatisé (PA) du Laboratoire de Génie de Production (LGP) de Tarbes ainsi que dans l'équipe de Modélisation d'Optimisation et de Gestion Intégrée de Systèmes d'Activités (MOGISA) du Laboratoire d'Analyse et d'Architecture des Systèmes (LAAS) de Toulouse. Il y a une trentaine d'année, le traitement des déchets se résumait à une simple mise en décharge. Depuis une conscience collective des problématiques environnementales a placé le traitement des déchets au cœur des préoccupations publiques. La gestion qui est faite des déchets ménagers constitue un enjeu environnemental, économique, social et de citoyennetés majeures, directement lié aux modes de consommation et à la société plus généralement. En France, les municipalités ou les collectivités locales, regroupant plusieurs municipalités, ont en charge de collecter et de convoyer les déchets vers leur lieu de traitement. Dans l'étude proposée, nous allons nous intéresser à la partie logistique, et plus précisément à la collecte et au transport des déchets ménagers et assimilés jusqu’à leur point de décharge (déchetteries, centre de transfert ou centre de traitement directement). Le but étant d’optimiser le transport de déchets tout en gardant une bonne qualité de service. Les enjeux mis en relief pour cette problématique sont les enjeux classiques imposés par toute étude visant à améliorer un service publique : un enjeu économique classique (minimiser les coûts de collecte et de transport), un enjeu environnemental évident (diminuer l'impact environnemental), un enjeu de qualité (satisfaire au mieux les usagers) et enfin un enjeu social (satisfaire les conditions de travail des employés). On va donc ici se concentrer sur l’aspect opérationnel journalier de la gestion. Lorsque celui-ci concerne une planification de trajet pour plusieurs véhicules en même temps qui doivent chacun faire leur circuit en livrant une certaine quantité de produit à chaque client cela se nomme le problème de tournées de véhicules (Vehicle Routing Problem). Ce problème pratique est souvent étudié pour des cas réels et se complexifie avec l’ajout de nombreux paramètres et contraintes, comme par exemple des contraintes d'horaire de passage sur certaines parties du réseau ; ou encore par l'ajout de plusieurs critères à optimiser en mêmes temps, comme par exemple les critères représentant les coûts et ceux représentant l'équilibrage de tournées, etc. / The study in this thesis focuses on the multipurpose logistics of household waste.
63

Kapacitní problém listonoše / Capacitated Arc Routing Problem

Franc, Zdeněk January 2014 (has links)
The Capacitated Arc Routing Problem has many applications in real life. The aim of this problem is to minimize the total cost at fulfilment of the requirements of arcs. The Capacitated Arc Routing Problem is an extension of the Chinese Postman Problem, which is a special type of the Vehicle Routing Problems. In this thesis is explained the issue of the Chinese Postman Problem and its extensions at first. Subsequently the applications of mathematical models are illustrated on a model example. However these mathematical models, which are searching the optimal solution, do not use so much in reality. Therefore the randomized heuristic algorithm for solving these problems is suggested and programmed in this thesis. Subsequently this heuristic was applied to case study of garbage collection in Podebrady city.
64

Aplikace heuristických metod v reálném rozvozním problému / Application of heuristic methods in real vehicle routing problem

Slavíková, Monika January 2014 (has links)
This thesis is continuation of the bachelor thesis "Model of delivery routes and placement logistics centers with opportunities of their optimization". It is about distribution problems and specifically a vehicle routing problem. The aim of this thesis is finding a solution of the vehicle routing problem which will be used repeatedly in the firm. The main task is achieving the lowest costs (total kilometers) with maximum utilization of vehicle capacity; in such conditions that all requirements of logistics centers will be satisfied and maximal capacity of vehicle will be tolerated. For calculation was used a solver Gurobi 6.0.3 in system MPL for Windows 4.2, which won't, however, provide the optimal solution and problem solving takes too long time. Next for calculation was used heuristics insert method and is written by VBA (Visual Basic for Applications) in MS Excel. Finally, there is a comparison of these methods with the original solution of the vehicle routing plan and solution of the bachelor thesis. Then the computational experiment was done, which tested effect to result, if other distribution center (starting point) will be bulit. The computational experiment was consist from heuristic insert method, solver Gurobi and heuristic saving algorithm from bachelor thesis.
65

Metody optimalizace plánování nákladní přepravy / Optimizations Methods for Freight Transportation

Gabonay, Michal January 2020 (has links)
The following work concerns the study of the evolutionary algorithm, which optimizes freight transport planning. The demand for freight transport is constantly increasing nowadays and with creating, implementing and using proper route planning we are able to significantly reduce transportation costs. However, it is preferably to implement it in companies with large numbers of served customers and with a sufficiently large fleet of vehicles.   The study starts by defining what fright transport planning problem is and by characterizing its existing specifications and variants. My work proceeds to give a background of the possible solutions to the multifaceted aspects of the problem. The specific subproblem I choose to focus on is the Vehicle routing problem with Pickup and Delivery for which I apply the optimization solution. In the main body of my thesis, I will elaborate on the chosen optimization solution which encompasses the genetic algorithm and evolutionary strategy. The aim of the study is to measure the suitability of the algorithms and techniques used, for which reason the final part of my work will deal with the analysis and evaluation of the experiments.
66

Portace nástroje OptaPlanner na Android / Port of OptaPlanner on Android

David, Tomáš January 2015 (has links)
This thesis deals with portation of the OptaPlanner tool to the Android operating system. The OptaPlanner is used for solving planning problems and it is completely written in the Java programming language which is also used for application development of the Android operating system. However, Android does not contain all of the Java Standard Edition Application Programming Interface libraries and porting of OptaPlanner to Android thus causes dependency problems. The result of the thesis is solution design and implementation of the problems mentioned above and model Android Vehicle Routing Problem application which uses ported OptaPlanner tool.
67

A New Approach for Solving the Disruption in Vehicle Routing Problem During the Delivery : A Comparative Analysis of VRP Meta-Heuristics

Kaja, Sai Chandana January 2020 (has links)
Context. The purpose of this research paper is to describe a new approach for solving the disruption in the vehicle routing problem (DVRP) which deals with the disturbance that will occur unexpectedly within the distribution area when executing the original VRP plan. The paper then focuses further on the foremost common and usual problem in real-time scenarios i.e., vehicle-breakdown part. Therefore, the research needs to be accomplished to deal with these major disruption in routing problems in transportation. Objectives. The study first investigates to find suitable and efficient metaheuristic techniques for solving real-time vehicle routing problems than an experiment is performed with the chosen algorithms which might produce near-optimal solutions. Evaluate the performance of those selected algorithms and compare the results among each other. Methods. To answer research questions, firstly, a literature review has been performed to search out suitable meta-heuristic techniques for solving vehicle routing problems. Then based on the findings an experiment is performed to evaluate the performance of selected meta-heuristic algorithms. Results. Results from the literature review showed that the meta-heuristic approaches such as. Tabu Search, Ant Colony Optimization, and Genetic Algorithmare suitable and efficient algorithms for solving real-time vehicle routing problems. The performance of those algorithms has been calculated and compared with one another with standard benchmarks. Conclusions. The performance of a Tabu Search algorithm is best among the other algorithms, followed by Ant Colony Optimization and Genetic Algorithm. Therefore, it has been concluded that the Tabu Search is the best algorithm for solving real-time disruption problems in VRP. The results are similar to the performance comparison of the selected algorithms and standard benchmarks are presented within the research.
68

Propuesta de mejora para reducir los tiempos de retraso en proyectos eléctricos en baja tensión para una empresa de servicios localizada en Lima aplicando Last Planner System, Vehicle Routing Problem y Workforce Management / Improvement proposal to reduce delay times in low voltaje electrical projects for a service company located in Lima by applying Last Planner System, Vehicle Routing Problem and Workforce Management

Avila Narvaez, Juan Agustin, Barriga Salas, Leonardo Abad 10 November 2019 (has links)
El presente estudio versa sobre la ejecución proyectos eléctricos en baja tensión, los cuales son ejecutados por una empresa de servicios cuyas operaciones se realizan en Lima. El capítulo 1 presenta la literatura asociada a la solución del problema, en donde se desarrolla el marco teórico de las metodologías propuestas. El capítulo 2 muestra el uso de las herramientas de la ingeniería industrial a efectos de identificar el problema: “retrasos en la ejecución de proyectos de baja tensión con reforma”. Esta problemática genera una pérdida anual de 381 miles de soles y un déficit de capital de trabajo de 11,500 miles de soles correspondiente al año 2017. El capítulo 3 plantea la solución de la problemática expuesta, para lo cual se definen dos etapas. La primera permite la eliminación del backlog acumulado hasta el mes de setiembre de 2018. La segunda se refiere al desarrollo de las metodologías: Last Planner System, Vehicle Routing Problem y Workforce Management. En el capítulo 4 se realiza la validación de las propuestas de las mejoras planteadas. En la primera etapa se contrataron 210 personas para eliminar el backlog y se validó una utilidad de 104 miles de soles. Para la segunda etapa, se implementó el proyecto cuadrillas propias y se utilizaron las metodologías Last Planner System y Vehicle Routing Problem.. Finalmente, se integró ambas metodologías con la incorporación de tecnología del tipo Workforce Management. Los resultados muestran una TIR del 20% y un VAN de 229 miles de soles. / The present research is about the implementation of low voltage electrical projects, which are performed by an utility company whose area of operations is the city of Lima. Chapter 1 describes the literature associated with the solution of the problem, where the theoretical framework of the above mentioned methodologies is developed. Chapter 2 describes the results obtained through the utilization of industrial engineering tools, with which the problem is identified as: "delays in the implementation of low voltage projects with reform". This problem generates an annual loss of 381 thousand soles and a working capital deficit of 11,500 thousand soles corresponding to year 2017. Chapter 3 proposes the solution of the exposed problem, for which two stages are defined. The first one allows the elimination of the accumulated backlog until September 2018. The second one refers to the development of the methodologies: Last Planner System, Vehicle Routing Problem and Workforce Management. Chapter 4 validates the proposed improvements. In the first stage, 210 people were hired to eliminate the backlog and as a result there was a profit of 104 thousand soles for the period within July and September. For the second stage, the project of own crews was implemented and there were used Last Planner System and the Vehicle Routing Problem as methodologies in order to optimize the route of the crews. Finally, both methodologies were integrated with the incorporation of the Workforce Management technology. The results show an IRR of 20% and a NPV of 229 thousand soles. / Trabajo de Suficiencia Profesional
69

Large Neighborhood Search for rich VRP with multiple pickup and delivery locations

Goel, Asvin, Gruhn, Volker 17 January 2019 (has links)
In this paper we consider a rich vehicle routing problem where transportation requests are characterised by multiple pickup and delivery locations. The problem is a combined load acceptance and generalised vehicle routing problem incorporating a diversity of practical complexities. Among those are time window restrictions, a heterogeneous vehicle fleet with different travel times, travel costs and capacity, multi-dimensional capacity constraints, order/vehicle compatibility constraints, and different start and end locations for vehicles. We propose iterative improvement approaches based on Large Neighborhood Search and a relatedness measure for transportation requests with multiple pickup and delivery locations. Our algorithms are characterised by very fast response times and thus, can be used within dynamic routing systems where input data can change at any time.
70

Robust Vehicle Routing in an Urban Setting / Robust fordonsruttning i en urban miljö

Lundkvist, Henrik January 2016 (has links)
In this thesis, the vehicle routing problem with stochastic, and time dependent, travel times is studied. The stochastic travel times are estimated from historical drive data. The variation of the drive times, as well as that of the variance, during the day was modeled.   The purpose of the thesis was to propose a method of handling the congestion related traffic impediments in an urban setting. Since the majority of times of delivery in the empirical test cases studied correlate with the time period of high traffic load, an efficient and robust handling of such traffic scenarios is of high importance.  It is shown that the stochastic models will shift the estimated arrivals to customers from the more volatile early and late extremes to more central regions of the time window. Previously delivered routes were evaluated both with the standard algorithm and the proposed stochastic algorithm. The difference between the actual drive times and the calculated drive times were analyzed by studying the correlation of the drive times between each customer in the route. It was shown that the routes of the proposed stochastic method increased this correlation. The drive times between nodes where also perturbed with a Gamma distributed noise. The results from the stochastic algorithm showed higher resilience to this disturbance than did the deterministic models. / I detta examensarbete har fordonsruttningsproblemet, VRP, med stokastiska och tidsberonds körtider behandlöats. De stokastiska körtiderna har estimerats från tidigare insamlad hasighetsdata. Modeller för körtidernas och variansernas förändring under dagen har tagits fram.   Syftet med examensarbetet var att föreslå en metod för hur påverkan på körtider av förutsägbar trafikträngsel i en urban trafikmiljö kan hanteras. Eftersom huvuddelen av alla leveranser sammanfaller med de tider på dygnet då trafikbelastning är som högst, ar är en effektiv och robust metod för att hantera sådana störningar av stor vikt. Det visas att den stokastiska modellen kommer att förflyttar ankomster från början och slutet av tidsfönstret till den mer okänsliga mittregionen. Tidigare, utförda leveranser studerades både med den ursprungliga deterministiska modellen och här framtagna stokastiska modellen. Skillnaden mellan de två analyserades genom att studera korrelationen mellan körtiderna som de beräknats av de två modellerna och de upmätta tiderna som de loggats av leveransfordonen. Det visas att korrelationen mellan körtiderna mellan de stokastiska körtiderna och de verkliga körtiderna är högre än korrelationen mellan de deterministiska körtiderna och de verkliga. Rutterna som föreslagits av den stokastiska modellen var också mer tlig mot störningar.

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