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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.
101

An investigation into the efficiency of the port / rail interface at the Port of Durban

Foolchand, Paris 30 June 2006 (has links)
Trade liberalization and resultantly globalization has led to the relative free flow of goods, services, capital and people. The transport system in South Africa must be highly reliable and rapid to contribute to economic development. The focus of this research study is on the Port/Rail Interface in the Port of Durban which critically assesses the transfer of goods particularly from rail transport to and from vessels within the port precinct. Some of the major constraints identified in the study related to poor infrastructure, operations and levels of services; lack of maintenance, availability of rolling stock, locomotives and cargo stacking space. Transnet's role is pivotal in providing efficient port and rail operations and is currently upgrading infrastructure, operations and capacity of the port and rail services. One of the main objectives of the study is to present recommendations to Transnet management that arise out of the shortcomings identified during the course of the research study. / Transport Economics / M. Comm.
102

Le rôle et la responsabilité des “Achats de Transport" dans la prise en compte des critères environnementaux et des émissions CO2 en France / The role of transportation procurement in achieving greener road freight transport : a case study of French companies

Touratier-Muller, Nathalie 12 September 2018 (has links)
Cette thèse de doctorat s’inscrit dans le cadre d’analyse du processus d'achat de transport. Plusieurs dispositifs gouvernementaux français ont été introduits pour sensibiliser les entreprises (chargeurs et transporteurs) vis-à-vis des émissions CO2 induites par le transport de marchandises. Le travail réalisé pendant cette thèse se sert de ces dispositifs comme « terrain d’études » pour comprendre quels leviers peuvent être mobilisés pour conduire les chargeurs (entreprises clientes) à mieux prendre en compte les contraintes environnementales. / This doctoral thesis forms part of the transportation purchasing process analysis. Several French government schemes have been introduced to raise companies’ awareness (shippers and carriers) regarding the CO2 emissions inducedby the transport of goods. The work achieved during this thesis uses these schemes as a "field study" to explore the impact of public policies and identifies levers that encourage shippers (client companies) to take the environmental footprint of products being transported into greater account. / Esta tesis doctoral se inscribe en el proceso de compra de transporte de mercancías y productos. El análisis se centra en el caso francés, ya que, durante los últimos años, el gobierno de dicha nación implantó y propulsó varios programas parasensibilizar a las empresas (cargadores y transportistas) con respecto a las emisiones de gases efecto invernadero y otros perjuicios medioambientales derivados del transporte de mercancías. A lo largo de la tesis doctoral, se realizan varios estudios de caso para explorar el impacto de las políticas públicas de contratación sostenible e identificar las medidas que podrían motivar a los cargadores (empresas clientes) a tener más en cuenta la huella medioambiental de los productos transportados.
103

Planejamento urbano e transporte urbano de carga: investigação de modelos de integração e aplicação do modelo Freturb em um recorte urbano em São Paulo. / Urban planning and urban freight: integrated moddeling investigation and the application of Freturb Model in an urban area in the city of São Paulo.

Thiago Canhos Montmorency Silva 16 June 2016 (has links)
A efervescência da cidade moderna somente é possível devido ao deslocamento contínuo de pessoas e mercadorias. A movimentação de bens é trivial para a realização das atividades comerciais, industriais e de prestação de serviços. Sua demanda, entretanto, é condicionada pelos padrões de uso e ocupação do solo e adensamento urbano. Esta pesquisa aborda aspectos da relação entre o transporte urbano de carga e a estruturação das áreas urbanas no Brasil. O principal objetivo é analisar a influência mútua entre a logística urbana e o uso e ocupação do solo no desenvolvimento de áreas urbanas no Município de São Paulo. Dessa forma, foram identificados, selecionados e analisados abordagens, metodologias e modelos aplicáveis à análise e proposição de diretrizes que integrem os condicionantes de desenvolvimento urbano e de transporte urbano de carga. Um modelo selecionado, o Freturb, foi aplicado em um recorte urbano do Município de São Paulo. Localizada na região de Santa Cecília e Higienópolis, a área de estudo foi modelada, primeiramente, de acordo com a sua configuração urbana atual e, em seguida, com as suas predições urbanas para os anos de 2025 e 2030, conforme os parâmetros urbanísticos do novo Plano Diretor Estratégico de São Paulo, em vigor desde 2014. Os resultados da modelagem foram abordados, qualitativamente, sob três categorias, que organizam parâmetros de planejamento e que se inter-relacionam no ambiente urbano: Aspectos do Uso e Ocupação do Solo, Aspectos da Logística e Aspectos do Tráfego Urbano. O trabalhou comparou, ainda, os resultados da configuração urbana atual do recorte urbano de São Paulo, com áreas urbanas francesas, selecionadas no Centro de Lyon e no 4o. Arrondissement de Paris. Essa comparação permitiu analisar a relação entre a empregabilidade e a densidade de movimentos da carga, nas três regiões urbanas. O estudo revelou que a área estudada em São Paulo necessita de mais movimentação de carga e exige mais do viário urbano e/ou é suprida por sistemas logísticos menos organizados, em relação às duas áreas francesas. Ainda, o porte e o perfil do estabelecimento podem incrementar o tempo de carga e descarga em uma área urbana. Finalmente, as predições urbanas, de 2025 e 2030, motivadas pelo novo Plano Diretor Estratégico do Município de São Paulo, permitiram avaliar e compreender os possíveis impactos do adensamento populacional e de empregos na demanda por transporte urbano de carga. E, verificar os possíveis impactos associados, tais como incremento em paradas em \"fila-dupla\" e ocupação viária por veículos de carga. / The effervescence of the modern city is only possible due to the continuous movement of people and goods. The movement of goods is trivial for of commercial, industrial and service activities. However, it is conditioned by the patterns of land use and urban density. This research approaches aspects of the relation between the urban freight transport and the structuring of urban areas in Brazil. The main objective is to analyze the mutual relationship among urban logistics and urban land use parameters on developing urban areas in São Paulo. Thus, applicable approaches, methodologies and models were identified, selected and analyzed, in light of their potential to support the integration of urban development and urban freight transport conditions. A selected model, the Freturb, was applied in an urban area in the city of São Paulo. Located in the region of Santa Cecilia and Higienopolis, the case study area was modeled, firstly, according to its current urban setting and then with their urban predictions for the years 2025 and 2030, according the new parameters of Master Plan of São Paulo, approved in 2014. The modeling results were classified and discussed accordingly to three aspects: Land Use Aspects, Logistics Aspects and Urban Traffic Aspects. The research also compared the results of the case study area located in São Paulo with other French urban areas, selected in the Center of Lyon and 4th. Arrondissement of Paris. Such a comparison allowed analyzing the relationship between the employability and the density of freight movements, in the three urban areas. The research revealed that the area in São Paulo requires more freight movement and urban road space and/or is supplied by less organized logistics systems, with regard to the latter two French areas. Also, the size and profile of the establishment can increase the loading and unloading time of operation in an urban area. Finally, the urban predictions, 2025 and 2030, motivated by the new Master Plan of São Paulo, allowed evaluating and understanding the possible impacts of population density and employment in demand for urban freight transport. And, they also allowed verifing the possible associated impacts, such as the increase in stops at \"double-park\" and road occupancy by goods vehicles.
104

Nätanslutning av en framtida elväg : En kartläggning av anslutningsmöjligheter för E4an mellan Gävle och Stockholm / Grid connection of a future electric road

Ekström, Amelie, Wänlund, Jessica January 2021 (has links)
The transport sector accounts for a third of Sweden’s total greenhouse gas emissions where cars and heavy trucks dominate the use of fossil fuels. The Swedish government is now intensifying the work for an electrified transport sector where electric roads could be an important part. Electric roads enable heavy vehicles to charge their batteries while driving, which is expected to contribute to environmentally friendly and time-efficient freight transports. To implement electric roads, availability of electric power along the electric roads will be required. This study presents a plan for connecting an electric road to the electricity grid in the electricity network area of Vattenfall Eldistribution. From the results, the idea was to present general conclusions from the experiences of the study, that could contribute in further implementation of electric roads.  The road that has been selected for the study was the E4 between Gävle and Stockholm. A model for calculating the power demand along the electric road has been modeled and connection possibilities to transformer stations has been investigated. The analysis was based on three scenarios where different degrees of strengthening of the existing electricity network were assumed. In addition, a forecast for 2030 and a cost estimation for each scenario has been carried out. The result of the study indicates that for road sections close to larger cities, there are a larger number of connection options in comparison to rural areas. Furthermore, the designed solution in the study required strengthening of the electricity grid and the investment cost was 362 million Swedish crowns.
105

Nätanslutning av en framtida elväg : En kartläggning av anslutningsmöjligheter för E4an mellan Gävle och Stockholm / Grid connection of a future electric road

Wänlund, Jessica, Ekström, Amelie January 2021 (has links)
The transport sector accounts for a third of Sweden’s total greenhouse gas emissions where cars and heavy trucks dominate the use of fossil fuels. The Swedish government is now intensifying the work for an electrified transport sector where electric roads could be an important part. Electric roads enable heavy vehicles to charge their batteries while driving, which is expected to contribute to environmentally friendly and time-efficient freight transports. To implement electric roads, availability of electric power along the electric roads will be required. This study presents a plan for connecting an electric road to the electricity grid in the electricity network area of Vattenfall Eldistribution. From the results, the idea was to present general conclusions from the experiences of the study, that could contribute in further implementation of electric roads. The road that has been selected for the study was the E4 between Gävle and Stockholm. A model for calculating the power demand along the electric road has been modeled and connection possibilities to transformer stations has been investigated. The analysis was based on three scenarios where different degrees of strengthening of the existing electricity network were assumed. In addition, a forecast for 2030 and a cost estimation for each scenario has been carried out. The result of the study indicates that for road sections close to larger cities, there are a larger number of connection options in comparison to rural areas. Furthermore, the designed solution in the study required strengthening of the electricity grid and the investment cost was 362 million Swedish crowns.
106

Affärsmodellspåverkan vid införande av HCT i Sverige : Implikationer för fordonstillverkare vid förändrade villkor för styckegodstransporter / Business model implications of HCT introduction in Sweden

Tham, Henrik, Mogard, Caroline January 2014 (has links)
Syfte – Studiens syfte är att öka kunskapen om hur fordonstillverkares affärsmodeller påverkas vid förändring av statliga regelverk genom att studera ett framtida införande av HCT i Sverige. HCT, High Capacity Transports, är ett samlingsnamn för lastbilar som är tyngre och/eller längre än vad gällande lagstiftning tillåter. Regelförändringen övervägs för att sänka kostnader och miljöpåverkan.  Metod – Arbetet har genomförts i form av en case-studie. För att studera påverkan på både fordonstillverkares och åkeriers affärsmodeller har intervjuer genomförts med varuägare, åkerier och förare inom fjärrtransporter av styckegods. Detta har kompletterats med löpande kontakt med uppdragsgivande fordonstillverkare samt deltagande i konferenser inom ramen för det nationella HCT-arbetet.  Resultat – Inget större modalskifte mellan järnvägs- och landsvägstransporter förväntas eftersom järnvägens infrastruktur styr transportvalet och inte påverkas av ett HCT-tillåtande. Vidare riskerar fordonstillverkare att sälja färre lastbilar vid ett tillåtande av HCT men genom anpassning av affärsmodellen kan de öka värdet per fordon. Detta värde kan ökas genom att sänka kundernas driftkostnad, maximera fordonens drifttid och föra kundens talan mot myndigheter.  Praktiskt bidrag – Studien har resulterat i ett nytt affärsmodellsramverk för fordonstillverkare vid införande av HCT. Ramverket visar att samtliga nuvarande värdeområden bör inkluderas i kommande affärsmodell och att flertalet får ökad betydelse. På grund av nya förutsättningar blir vissa av dessa områden dessutom svårare att uppnå samtidigt som nya områden kan läggas till.  Vetenskapligt bidrag – Genom att öka kunskapen om affärsmodellspåverkan vid förändring av statliga regelverk utvidgar studien befintlig teori om förändringar av affärsmodeller. Studien belyser även vikten av att studera hela leverantörskedjan vid sådana förändringar. Detta eftersom statliga regelverk styr förutsättningarna för flera aktörer med starka inbördes relationer. Därmed sprider sig effekterna av en regelverksförändring till övriga aktörer i kedjan. / Purpose – The purpose of this study is to increase the knowledge about how legislative changes affect the business model of vehicle manufactures by studying a future allowance of HCT in Sweden. HCT, High Capacity Transports, is a generic term for trucks exceeding today’s weight and/or length regulations. Reasons for implementing HCT include reducing costs and environmental consequences. Method – Effects of legislative changes have been studied through a case-study of how HCT would affect the Swedish transport system. In order to study business model implications for both vehicle manufactures and hauliers, interviews have been held with transport buyers, hauliers and drivers within long distance haulage of break bulk cargo. This has been complemented by continuous contact with the commissioning vehicle manufacturer and participation in HCT conferences. Findings – Findings indicate that there will be no major modal shift between railway and road since the railway infrastructure determines the modal choice and is unaffected by HCT. Furthermore findings show that vehicle manufactures risk to sell fewer vehicles in case of HCT allowance but a business model adaption can increase the value per vehicle. This can be achieved by reducing customer operating costs, increasing vehicle uptime and being the voice of the customer against authorities. Practical implications – The study has resulted in a HCT business model framework for vehicle manufactures. The framework shows that all present value areas should be included in a future business model and that several areas will increase in importance. In the effect of new conditions several areas will become more difficult to fulfill. Furthermore new areas will be added. Theoretical implications – This study expands current theories within business model changes by increasing knowledge about how legislative changes affect business models. Furthermore this study highlights the importance of studying the whole supply chain in the event of these changes. The reason for this is that legislations affect the conditions for several players with strong peer relationships. Thereby effects due to changed legislations will spread to other players in the chain.
107

Estimating the load weight of freight trains using machine learning

Kongpachith, Erik January 2023 (has links)
Accurate estimation of the load weight of freight trains is crucial for ensuring safe, efficient and sustainable rail freight transports. Traditional methods for estimating load weight often suffer from limitations in accuracy and efficiency. In recent years, machine learning algorithms have gained significant attention and use cases within the railway industry due to their strong predictive capabilities for classification and regression tasks. This study aims to present a proof of concept in the form of a comparative analysis of five machine learning regression algorithms: Polynomial Regression, K-Nearest Neighbors, Regression Trees, Random Forest Regression, and Support Vector Regression for estimating the load weight of freight trains using simulation data. The study utilizes two comprehensive datasets derived from train simulations in GENSYS, a simulation software for modeling rail vehicles. The datasets encompasses various driving condition factors such as train speed, track conditions and running gear configurations. The algorithms are trained and evaluated on these datasets and their performance is evaluated based on the root mean squared error and R2 metrics. Results from the experiments demonstrate that all five machine learning algorithms show promising performance for estimating the load weight. Polynomial regression achieves the best result for both of the datasets when using many features of the datasets are considered. Random forest regression achieves the best result for both of the data sets when a small number features of the datasets are considered. Furthermore, it is suggested that the methodical approach of this study is examined on real world data from operating freight trains to assert the proof of concept in a real world setting. / Noggrann uppskattning av godstågens lastvikt är avgörande för att säkerställa säkra, effektiva och hållbara godstransporter via järnväg. Traditionella metoder för att uppskatta lastvikt lider ofta av begränsningar i noggrannhet och effektivitet. Under de senaste åren har maskininlärningsalgoritmer fått betydande uppmärksamhet och användningsfall inom järnvägsindustrin på grund av deras starka prediktiva förmåga för klassificerings- och regressionsproblem. Denna studie syftar till att presentera en proof of concept i form av en jämförande analys av fem maskininlärningalgoritmer för regression: Polynom regression, K-Nearest Neighbors, Regression träd, Random Forest Regression och Support Vector Regression för att uppskatta lastvikten för godståg med hjälp av simuleringsdata. Studien använder två omfattande dataset konstruerade från tågsimuleringar i GENSYS, en simuleringsprogramvara för modellering av järnvägsfordon. Dataseten omfattar olika körfaktorer såsom tåghastighet, spårförhållanden och vagns konfigurationer. Algoritmerna tränas och utvärderas på dessa dataset och deras prestanda utvärderas baserat på root mean squared error och R2 måtten. Resultat från experimenten visar att alla fem maskininlärningsalgoritmerna visar lovande prestanda för att uppskatta lastvikten. Polynom regression uppnår det bästa resultatet för båda dataset när många variabler i datan beaktas. Random Forest Regression ger det bästa resultatet för båda dataset när ett mindre antal variabler i datan beaktas. Det föreslås det att det metodiska tillvägagångssättet för denna studie undersöks på verklig data från aktiva godståg för att fastställa en proof of concept på en verklig världsbild.

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