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A behavioural analysis of modal choice in freight transportJeffs, V. P. January 1985 (has links)
No description available.
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Evaluation of Freight and Transit Signal Priority Strategies for Improving Transportation Operations in Urban CorridorsUnknown Date (has links)
Freight transportation is a significant component of the nation’s economy. However, the augmented volume of the freight movements contributed to continuously increasing congestion on the urban road networks, that affects the timeliness and reliability of freight transportation. In addition, congestion has a negative impact on the transit operations as well. Various studies conducted on multi-modal corridors recognized the importance of the simultaneous performance of freight and transit operations. Thus, Intelligent Transportation System (ITS) components, such as Freight Signal Priority (FSP) and Transit Signal Priority (TSP), present traffic operations strategies "shaped" to give priority, reduce delay and travel time, and overall improve the performance of freight and transit movements, respectively. The primary objective of the thesis refers to evaluate possible improvements in freight mobility, while sustaining good transit services and minimizing congestion on the multi-modal corridor, through simultaneous implementation of the FSP and the TSP. The effectiveness of the newly established criteria was evaluated through real-world case study on a micro-simulation platform. The results showed significant improvements on all the vehicle movements. / Includes bibliography. / Thesis (M.S.)--Florida Atlantic University, 2019. / FAU Electronic Theses and Dissertations Collection
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A Quantitative Framework for Assessing Vulnerability and Redundancy of Freight Transportation NetworksJansuwan, Sarawut 01 May 2013 (has links)
Freight transportation networks are an important component of everyday life in modern society. Disruption to these networks can make peoples’ daily lives extremely difficult as well as seriously cripple economic productivity. This dissertation develops a quantitative framework for assessing vulnerability and redundancy of freight transportation networks. The framework consists of three major contributions: (1) a two- stage approach for estimating a statewide truck origin-destination (O-D) trip table, (2) a decision support tool for assessing vulnerability of freight transportation networks, and (3) a quantitative approach for measuring redundancy of freight transportation networks.The dissertation first proposes a two-stage approach to estimate a statewide truck O-D trip table. The proposed approach is supported by two sequential stages: the first stage estimates a commodity-based truck O-D trip table using the commodity flows derived from the Freight Analysis Framework (FAF) database, and the second stage uses the path flow estimator (PFE) concept to refine the truck trip table obtained from the first stage using the truck counts from the statewide truck count program. The model allows great flexibility of incorporating data at different spatial levels for estimating the truck O- D trip table. The results from the second stage provide us a better understanding of truck flows on the statewide truck routes and corridors, and allow us to better manage the anticipated impacts caused by network disruptions.A decision support tool is developed to facilitate the decision making system through the application of its database management capabilities, graphical user interface, GIS-based visualization, and transportation network vulnerability analysis. The vulnerability assessment focuses on evaluating the statewide truck-freight bottlenecks/chokepoints. This dissertation proposes two quantitative measures: O-D connectivity (or detour route) in terms of distance and freight flow pattern change in terms of vehicle miles traveled (VMT). The case study adopts a “what-if” analysis approach by generating the disruption scenarios of the structurally deficient bridges in Utah due to earthquakes. In addition, the potential impacts of disruptions to multiple bridges in both rural and urban areas are evaluated and compared to the single bridge failure scenarios.This dissertation also proposes an approach to measure the redundancy of freight transportation networks based on two main dimensions: route diversity and network spare capacity. The route diversity dimension is used to evaluate the existence of multiple efficient routes available for users or the degree of connections between a specific O-D pair. The network spare capacity dimension is used to quantify the network- wide spare capacity with an explicit consideration of congestion effect. These two dimensions can complement each other by providing a two-dimensional characterization of freight transportation network redundancy. Case studies of the Utah statewide transportation network and coal multimodal network are conducted to demonstrate the features of the vulnerability and redundancy measures and the applicability of the quantitative assessment methodology.
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CO2 Emission Reduction Practices of Road Freight Transportation that could be implemented in small and medium sized logistics enterprises in LatviaLaursone, Gunita, Dislers, Karlis, Keremet, Maxim January 2011 (has links)
No description available.
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Investigation of risks and value with services used by transporters : A case study within the road freight transportation industryWästerlund, Elin, Yurtkulu, Emine Zehra January 2012 (has links)
The transportation industry is a rapidly changing business. As a result of the increased demand for transportation and the tougher demands on transportation companies’ performance, it is important that they have good and reliable processes that are able to live up to those demands in a highly competitive market. Increased performance is important for transportation companies in order to create value for its customers and steps that can help them to achieve this can be seen as valuable. In Sweden, vehicle manufacturers offer extended services in order to respond to the changes on the transportation market. However, there is a knowledge gap about the experiences of using a product together with extended services that has a more service dominant logic compared to buying and using only the product. This research is conducted as a multiple-case study with five companies within the freight transportation industry to investigate their experiences of using extended services regarding risk and value concepts. To be able to conduct this research, literature and empirical study has been conducted through the collection of secondary- and primary data such as face-to- face interviews. The result of this study shows that there are several determining factors, which the case companies consider when determining how to resolve the issues of extended services such as financial aspects, location of workshop, flexibility, size of transporter, and control. Fur- thermore was advantages of using extended services offered by vehicle manufacturers found that related to financial advantages, increased customer service levels, assurance that best service will be provided, and increased up-time. In addition to that it was found that these services could help transportation companies to reduce some risks related to the financial- and goods/physical risk categories. In contrast were advantages of not using extended services offered by vehicle manufacturers found such as financial benefits, possibilities to cooperate, flexibility, increased up-time as a result of location, and control. The loss of control was a risk found that could be decreased if not using vehicle manufacturers extended services.
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Simulation framework of port operation and recovery planningMeng, Si 30 April 2011 (has links)
This study proposes a framework of simulation tool suites for ports to evaluate their response to disaster crisis and port security policies. The focus is containerized cargos that are imported through ports in the U.S. with final destinations also in the U.S. A crisis, such as a man-made or natural disaster, may cause a delay at the seaport. The down time of ports may result in severe economic losses. Thus, when a seaport cannot normally operate, it is important to minimize the impact caused by the disrupted freight flow. Port security policies also have a significant impact on the port operation efficiency. This model developed in this study evaluates the performance of re-routing strategies under different crisis scenarios and can help the user to find an effective re-routing decision and analyze security policies of a port. This model also analyzes security policies of the simulation port.
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Transportation Service Provider Collaboration Problem: Potential Benefits and Solution ApproachesRoesch, Robert Steven 28 February 2017 (has links)
Truck-based freight transportation continues to play a vital role in the delivery of goods in the United States. Despite its size and importance, the truck transportation industry continues to struggle with fulfilling transportation requests in an efficient and sustainable manner. One potential solution to alleviate many of the current truck industry problems is for transportation service providers (TSPs) to collaborate by sharing volume, resources, and facilities. This research introduces the Transportation Service Provider Collaboration Problem (TSP-CP) to demonstrate the benefits of using optimal freight routing and consolidation decisions for collaborating TSPs. A mathematical model for the TSP-CP is introduced to describe the problem in detail. Additionally, two separate adaptive large neighborhood search (ALNS) heuristics are developed to provide solutions to industry representative problem instances. Finally, the benefits and insights achieved by enabling collaboration between TSPs using the TSP-CP are identified using industry representative data sets.
The representative data sets were derived from actual freight data provided by a freight pooling company that manages collaboration among TSPs. Carriers were chosen from the industry data to evaluate collaborative partnerships and to gain insights on the effects of partnership characteristics on overall benefit as well as the benefits obtained by individual carriers. The computational results suggested collaboration among TSPs offers the potential for substantial reductions in the total distance required to deliver all loads, in the number miles that were traveled completely empty, and the number of containers required for delivery compared to individual performance. Additionally, collaboration increased delivery resource capacity utilization as measured by the percentage of weighted full miles. Detailed analysis of the results from the TSP-CP revealed new insights into the collaboration between full truckload and less-than truckload carriers that have not been quantified or highlighted in previous research. These insights included the effect that an individual carrier's type and size had on the amount of benefit received to each carrier. Finally, the results highlighted the importance of building collaborative partnerships that consider a carrier's geographic location. / Ph. D.
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Indicadores de desempenho do transporte rodoviário de cargas / Performance indicators of road freight transportationSilva, Alexandre Lima Marques da 26 March 1999 (has links)
É de fundamental importância que as empresas do setor de transporte rodoviário de cargas mantenham um processo contínuo de avaliação da sua produtividade. Tendo em vista que o setor é bastante competitivo, as empresas de transporte de carga necessitam rever suas políticas operacionais e de marketing, oferecendo serviços de qualidade e otimizando a utilização de seus recursos e insumos. O objetivo deste trabalho é propor um conjunto de indicadores de desempenho relacionados à produtividade que possa ser utilizado pelas empresas de transporte de carga. Com base na literatura técnica e em questionários aplicados a algumas empresas, é proposto um conjunto de indicadores de desempenho, segundo seu grau de importância e de facilidade de implantação. O resultado deste trabalho revela que as empresas utilizam de forma parcial as medidas de desempenho, que são fundamentais no processo de redução de custos e aumento na produtividade global. / lt is of fundamental importance that road freight transportation enterprises maintaining a continuous evaluation process of their productivity. As such sector is excessively competitive, freight transportation enterprises need to verify their operational and marketing policies, offering services of good quality and optimizing the utilization of their resources and inputs. The aim of this study is to propose a set of performance indicators related with productivity which can be used by freight transportation enterprises. From technical literature index collections and questionnaires sent by their enterprises, a set of performance indicators is proposed, according to importance level and implementation facility. The result of this research reveals that currently few enterprises use in a controlled way these performance indicators that are fundamental in the cost reduction process and increasing the global productivity.
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Uma abordagem de resolução integrada para os problemas de roteirização e carregamento de veículosAraújo, Rafael Roco de January 2010 (has links)
O transporte de cargas desempenha um papel fundamental nos sistemas logísticos uma vez que possibilita o fluxo de produtos entre os elementos dos canais de distribuição, além de representar um elevado percentual de participação nos custos logísticos totais. Desse modo, a eficiência dos serviços de transporte depende diretamente de um adequado processo de planejamento em nível estratégico, tático e operacional. O transporte rodoviário, em particular, apresenta em nível operacional, problemas de elevada complexidade como a roteirização e o carregamento de veículos. Durante os últimos 50 anos estes problemas vêm sendo objeto de intensos estudos e desenvolvimentos, porém de forma separada, conduzindo a resultados difíceis de serem implementados nas situações práticas, devido à grande interdependência existente entre roteirização e carregamento de veículos. A resolução integrada destes dois problemas é recente na literatura, o que abre um campo bastante promissor para novos desenvolvimentos. Assim, esta tese tem como objetivo propor uma abordagem integrada de resolução para o problema de roteirização e carregamento de veículos onde, além das restrições de carregamento tridimensionais, as restrições de tempo de ciclo e distribuição de peso nos eixos são consideradas. Este modelo adota uma abordagem aproximativa que combina o uso de heurísticas para construção dos carregamentos com a metaheurística de Busca Tabu para melhoria dos roteiros de entrega. Para execução dos testes computacionais é proposto um conjunto de 12 instâncias que buscam simular situações práticas encontradas nas operações de entrega feitas por empresas de transporte e prestadores de serviços logísticos. A partir desse conjunto de instâncias são construídos cenários que avaliam o uso de diferentes tipos de veículos e os respectivos custos operacionais. Testes complementares realizados com um conjunto de 27 instâncias disponíveis na literatura, demonstram a capacidade do modelo proposto de atingir boas soluções em um tempo de processamento aceitável. / Freight transportation plays a fundamental role in logistics systems, once it enables the product flow between distribution channels elements, besides to represents a high percentage of participation on the total logistics costs. In this way, transport service efficiency depends directly of a suitable process of planning in strategic, tactical and operational level. The road transportation, in particular, shows in operational level high complexity problems as routing and loading of vehicles. During the last 50 years, these problems has been object of deep studies and developments, but in a separate manner, leading to results that are difficult to implement in practical situation due to the interdependence between routing and loading of vehicles. The integrated resolution of these two problems is recent in the literature, what opens a quite promising field for new developments. Thus, this thesis has as objective to propose an integrated resolution approach for the vehicle routing and loading where, besides the three-dimensional loading constraints, constraints, the time cicle and the distribution load over de axles are considered. This model adopts an approximated approach that combines the use of heuristics for loading construction with Tabu Search metaheuristics to improve the delivery routes. For computational tests execution is proposed a 12 instances set that tries to simulate practical situation found in delivery operations made by freight firms and thirty party logistics. From this instance set, it is built scenarios that evaluate the use of different vehicle types and the respectives operational costs. Complementary tests made with a 27 instances set available in literature show the capacity of proposed model to get good solutions in an acceptable computational time.
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An Inventory Model With Two Truckload Transportation and Quantity DiscountsSanthanam, Ramesh T 28 October 2005 (has links)
Transportation plays a vital role in the movement of raw materials and finished goods from one place to another. Trucks play a vital role in the movement of materials and are indispensable part of almost every shipment, both domestic and international. On the average, thirty-nine percent of the total logistics cost is spent on transportation. Therefore reducing the transportation cost may significantly reduce the total logistics cost.
The total annual logistics cost considered in this research includes ordering cost, material cost, transportation cost and inventory holding cost. The main objective of this research is to develop algorithms for finding the optimal ordering quantity that minimizes total annual logistics cost, when the suppliers offer No quantity discounts All-unit quantity discounts Incremental quantity discounts
This research considers truckload transportation where two truck sizes are available. The algorithm developed in this research will identify the optimum ordering quantity and the optimum number of trucks required to ship the ordering quantity. MATLAB programming of the algorithm will analyze the factors that affect that the total annual logistics cost.
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