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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.
21

Blockchain Technology in Transportation Management : A case study with Rhenus Logistics AB

Ewald, Lina, Hjortstam, Arvid, Wilén, Jesper January 2021 (has links)
Purpose: In this study, areas of use of blockchain technology in transportation management will be discussed. The purpose is to contribute with theoretical research of advantages and disadvantages of blockchain technology in transportation management before an implementation at Rhenus Logistics.   Methodology: Through interviews and literature, ways of using blockchain in transportation management is researched. A case study is set up, to further analyze the research topic from the view of an individual third-party logistic company.  Findings: Results showed that for a third-party logistic provider to successfully use blockchain technology within transportation management, it is important to have the entire network onboard in the process. If so, functionalities such as track and trace, digital handling of paperwork and smart contracts could be used. The advantages of using blockchain technology for transportation management at Rhenus Logistics were found to be trust, transparency, traceability, efficiency, cost-saving opportunities and the use of smart contacts. Identified disadvantages for Rhenus Logistics was that blockchain is costly, stakeholders are hesitant to get involved, smart contracts are not considerate of blurry lines in real life practice and there is a challenge in finding an accurate blockchain design for their business model.
22

[en] PROPOSAL OF PROCESSES TO ASSIST THE MANAGEMENT OF THE TRANSPORTATION SERVICE CARRIED OUT BY THE CENTRAL TRANSPORTATION OFFICE / [pt] PROPOSTA DE PROCESSOS QUE AUXILIE A GESTÃO DO SERVIÇO DE TRANSPORTE REALIZADO PELO ESTABELECIMENTO CENTRAL DE TRANSPORTES

DIEGO DE CARVALHO 22 January 2018 (has links)
[pt] Esta dissertação tem como finalidade apresentar propostas de processos que apoiam processos de tomadas de decisão atinentes à gestão da atividade de transporte realizada pelo Estabelecimento Central de Transportes (ECT). O estudo permitiu uma identificação precisa do cenário e da situação em que se encontra o ECT, para o cumprimento das operações de transporte impostas pela Base de Apoio Logístico do Exército (Ba Ap Log Ex). Sendo assim, o estudo proposto por meio desta dissertação enfatiza a necessidade de avaliação das atividades desenvolvidase sugere a implementação dos processos de integração das seções, seleção de pessoal, seleção do agente suprido, pagamento de diária ou gratificação de representação e processo de alocação do veículo à carga, que permitirão elevar o nível da gestão das operações logísticas.A pesquisa foi desenvolvida em consonância com as boas práticas transcritas em trabalhos científicos e em diretrizes presentes em leis e regulamentações destinadas à gestão de transporte no âmbito da Força Terrestre. A dissertação não apresenta estudos relacionados à mensuração dos custos envolvidos na gestão do serviço de transporte. Como instrumentos de pesquisas foram utilizados Matriz SWOT, 5W2H, Análises Pós Ação (APA), Diagrama de Causa e Efeito, entrevistas com os gestores, análise documental e o ciclo PDCA nos processos de gestão de transporte. / [en] This dissertation aims to present proposals for processes that support decision-making processes related to the management of the transportation activity carried out by the Estabelecimento Central de Transportes (ECT). The study allowed a precise identification of the scenario and the situation in which the ECT is located, in order to comply with the transport operations imposed by the Base de Apoio Logístico do Exército (Ba Ap Log Ex). Thus, the study proposed through this dissertation emphasizes the need to evaluate the activities developed and suggests the implementation of the processes of integration of the sections, selection of personnel, selection of agent supplied, daily payment or representation bonus and allocation process of the the level of management of logistics operations. The research was developed in line with good practices transcribed in scientific work and in guidelines in laws and regulations for the management of transport within the Land Force. The dissertation does not present studies related to the measurement of the costs involved in the management of the transportation service. SWOT Matrix, 5W2H, Post-Action Analysis (APA), Cause and Effect Diagram, interviews with managers, documentary analysis and the PDCA cycle in the transport management processes were used as research instruments.
23

Understanding and exploiting mobility in wireless networks / Comprendre et exploiter la mobilité dans les réseaux sans fil

Uppoor, Sandesh 29 November 2013 (has links)
Le degré de pénétration du marché des appareils intelligents tels que les smartphones et les tablettes avec les technologies de communication embarquées comme le WiFi, 3G et LTE a explosé en moins d’une décennie. En complément de cette tendance technologique, les applications des réseaux sociaux ont virtuellement connectées une grande partie de la popula- tion, en génerant une demande croissante de trafic de données vers et depuis l’infrastructure de communication. Les communications pervasives ont aussi acquis une importance dans l’industrie automobile. L’émergence d’une gamme impressionnante d’appareils intelligents dans les véhicules a permis des services tels que : l’assistante au conducteur, l’infotainment, le suivi à distance du véhicule, et la connectivité aux réseaux sociaux même en déplacement La demande exponentielle de connectivité a encore défié les fournisseurs de services de télé- communications pour répondre aux attentes des utilisateurs.L’objectif de cette thèse est de modéliser et comprendre la mobilité dynamique des utilisateurs à grande vitesse et leurs effets sur les architectures de réseau sans fil. Compte tenu de l’ importance du développement de notre étude sur une représentation réal- iste de la mobilité des véhicules, nous étudions tout d’abord les approches les plus populaires pour la génération de trafic routier synthétique et discutons les caractéristiques des ensem- bles de données accessibles au public qui décrivent des mobilités véhiculaires. En utilisant l’information des déplacements de la population dans une région métropolitaine, les données détaillées du réseau routier et les modèles réalistes des conduites microscopiques, nous pro- posons un jeu de données de mobilité véhiculaire original qui redéfinit l’état de l’art et qui replie la circulation routière de façon réaliste dans le temps et dans l’espace. Nous étudions ensuite l’impact des dynamiques des mobilité du point de vue de la couverture cellulaire en présence d’un déploiement réel des stations de base. En outre, en examinant les effets de la mobilité des véhicules sur les réseaux autonomes, nous voyons des possibilités pour les futurs paradigmes de réseaux hétérogènes. Motivés par l’évolution dynamique dans le temps, de la mobilité des véhicules observée dans notre jeux de données, nous proposons également une approche en ligne pour prédire les flux de trafic macroscopiques. Nous analysons les paramètres affectant la prédiction de la mobilité en milieu urbain. Nous dévoilons quand et où la gestion des ressources réseaux est la plus cruciale pour accueillir le trafic généré par les utilisateurs à bord. Ces études révèlent de multiples opportunités de gestion intelligente des transports, soit pour construire de nouvelles routes, soit pour l’installation de bornes de recharge électriques, ou pour la conception de systèmes de feux de circulation intelligents, contribuant ainsi à la planification urbaine. / The market penetration of smart devices like smartphones and tablets with embedded communication technologies like WiFi, 3G and LTE has exploded in less than a decade. Complementing this technological trend, social networking applications have virtually connected a large portion of the population generating an ever-growing data traffic demand on the communication infrastructure. Pervasive communications have gained significance in the automobile industry as well, with the emergence of an impressive range of in-vehicle smart devices enabling driver assistance, infotainment, over-the-air vehicle monitoring, and even social connectivity on the move. This surge in the demand for connectivity has further challenged telecommunication service providers to meet the expectations of high-speed network users. The goal of this thesis is to model and understand the mobility dynamics of high-speed users and their effect on wireless network architectures. Given the importance of developing our study on a realistic representation of vehicular mobility, we first survey the most popular approaches for the generation of synthetic road traffic and discuss the features of publicly available vehicular mobility datasets. Using original travel demand information of the population of a metropolitan area, detailed road network data and realistic microscopic driving models, we propose a novel state-of-art vehicular mobility dataset that closely mimics the real-world road traffic dynamics in both time and space. We then study the impact of such mobility dynamics from the perspective of wireless cellular network architecture in presence of a real-world base station deployment. In addition, by discussing the effects of vehicular mobility on autonomous network architecture, we hint at the opportunities for future heterogenous network paradigms. Motivated by the time-evolving mobility dynamics observed in our original dataset, we also propose an online approach to predict near-future macroscopic traffic flows. We analyze the parameters affecting the mobility prediction in an urban environment and unveil when and where network resource management is more crucial to accommodate the traffic generated by users onboard. Such studies unveil multiple opportunities in transportation management either for building new roads, installing electric charging points, or for designing intelligent traffic light systems, thereby contributing to urban planning.
24

Two-stage combinatorial optimization framework for air traffic flow management under constrained capacity

Kim, Bosung 08 June 2015 (has links)
Air traffic flow management is a critical component of air transport operations because at some point in time, often very frequently, one of more of the critical resources in the air transportation network has significantly reduced capacity, resulting in congestion and delay for airlines and other entities and individuals who use the network. Typically, these “bottlenecks” are noticed at a given airport or terminal area, but they also occur in en route airspace. The two-stage combinatorial optimization framework for air traffic flow management under constrained capacity that is presented in this thesis, represents a important step towards the full consideration of the combinatorial nature of air traffic flow management decision that is often ignored or dealt with via priority-based schemes. It also illustrates the similarities between two traffic flow management problems that heretofore were considered to be quite distinct. The runway systems at major airports are highly constrained resources. From the perspective of arrivals, unnecessary delays and emissions may occur during peak periods when one or more runways at an airport are in great demand while other runways at the same airport are operating under their capacity. The primary cause of this imbalance in runway utilization is that the traffic flow into and out of the terminal areas is asymmetric (as a result of airline scheduling practices), and arrivals are typically assigned to the runway nearest the fix through which they enter the terminal areas. From the perspective of departures, delays and emissions occur because arrivals take precedence over departures with regard to the utilization of runways (despite the absence of binding safety constraints), and because arrival trajectories often include level segments that ensure “procedural separation” from arriving traffic while planes are not allowed to climb unrestricted along the most direct path to their destination. Similar to the runway systems, the terminal radar approach control facilities (TRACON) boundary fixes are also constrained resources of the terminal airspace. Because some arrival traffic from different airports merges at an arrival fix, a queue for the terminal areas generally starts to form at the arrival fix, which are caused by delays due to heavy arriving traffic streams. The arrivals must then absorb these delays by path stretching and adjusting their speed, resulting in unplanned fuel consumption. However, these delays are often not distributed evenly. As a result, some arrival fixes experience severe delays while, similar to the runway systems, the other arrival fixes might experience no delays at all. The goal of this thesis is to develop a combined optimization approach for terminal airspace flow management that assigns a TRACON boundary fix and a runway to each flight while minimizing the required fuel burn and emissions. The approach lessens the severity of terminal capacity shortage caused by and imbalance of traffic demand by shunting flights from current positions to alternate runways. This is done by considering every possible path combination. To attempt to solve the congestion of the terminal airspace at both runways and arrival fixes, this research focuses on two sequential optimizations. The fix assignments are dealt with by considering, simultaneously, the capacity constraints of fixes and runways as well as the fuel consumption and emissions of each flight. The research also develops runway assignments with runway scheduling such that the total emissions produced in the terminal area and on the airport surface are minimized. The two-stage sequential framework is also extended to en route airspace. When en route airspace loses its capacity for any reason, e.g. severe weather condition, air traffic controllers and flight operators plan flight schedules together based on the given capacity limit, thereby maximizing en route throughput and minimizing flight operators' costs. However, the current methods have limitations due to the lacks of consideration of the combinatorial nature of air traffic flow management decision. One of the initial attempts to overcome these limitations is the Collaborative Trajectory Options Program (CTOP), which will be initiated soon by the Federal Aviation Administration (FAA). The developed two-stage combinatorial optimization framework fits this CTOP perfectly from the flight operator's perspective. The first stage is used to find an optimal slot allocation for flights under satisfying the ration by schedule (RBS) algorithm of the FAA. To solve the formulated first stage problem efficiently, two different solution methodologies, a heuristic algorithm and a modified branch and bound algorithm, are presented. Then, flights are assigned to the resulting optimized slots in the second stage so as to minimize the flight operator's costs.

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