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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.
1

A Study of System Performance Measures for Intermodal Transportation

Wang, Haiyuan 08 May 2004 (has links)
In the current literature and practice, no systematic and user-oriented performance measures are available to evaluate intermodal transportation and facilitate mode-choice decision-making. Most existing transportation measures are defined for one specific mode and are not consistent with each other. This research establishes a systematic and user-oriented performance measurement system for intermodal transportation. Five major categories of performance measures are identified: mobility and reliability, safety, environmental impact, long term transportation cost efficiency, and economic impact. For each category, several quantitative measures are given to capture the features of the system and evaluate how well transportation systems can meet the needs of their users, who are investors (including government agents and stakeholders), individuals, industries, and the society (or the public). The proposed measures are scalable so that they can be used to compare systems with different sizes. Since none of them is mode specific, no matter how many modes and what kinds of modes are involved, a transportation system can be evaluated by the measure set. This research tries to avoid any overlap or omission among the measures and distinguish performance measures from factors. A transportation system can be improved through changing some factors, like capacity, but project priority should be decided based on measures rather than factors. The proposed measures are also verified by a survey conducted by this research and some industrial practices. In the thesis, a case study on the State of Mississippi is conducted based on the identified performance measures. The measures with the case study can help to promote transportation intermodalism in the U.S. and quantitatively demonstrate the benefits of intermodal transportation. The proposed measures differ in many aspects from traditional measures. The proposed set of performance measurement system can have a significant impact on development of U.S. transportation system.
2

Hybrid simulation and optimization approach for green intermodal transportation problem with travel time uncertainty

Hrusovsky, Martin, Demir, Emrah, Jammernegg, Werner, van Woensel, Tom 09 1900 (has links) (PDF)
The increasing volumes of road transportation contribute to congestion on road, which leads to delays and other negative impacts on the reliability of transportation. Moreover, transportation is one of the main contributors to the growth of carbon dioxide equivalent emissions, where the impact of road transportation is significant. Therefore, governmental organizations and private commercial companies are looking for greener transportation solutions to eliminate the negative externalities of road transportation. In this paper, we present a novel solution framework to support the operational-level decisions for intermodal transportation networks using a combination of an optimization model and simulation. The simulation model includes stochastic elements in form of uncertain travel times, whereas the optimization model represents a deterministic and linear multi-commodity service network design formulation. The intermodal transportation plan can be optimized according to different objectives, including costs, time and CO2e emissions. The proposed approach is successfully implemented to real-life scenarios where differences in transportation plans for alternative objectives are presented. The solutions for transportation networks with up to 250 services and 20 orders show that the approach is capable of delivering reliable solutions and identifying possible disruptions and alternatives for adapting the unreliable transportation plans.
3

Development of dry ports in Småland, Sweden : Comparing the cases of Nässjö and Vaggeryd

Haak, Frans Willem Gerard, Tamosaityte, Dainora January 2012 (has links)
Problem: Due to several changes in the market, economy, industry and the environment there was an increasing trend in emerging dry ports/inland terminals throughout Sweden. A dry port is still a young term in the transportation field gaining more popularity and attention. The gap in literature was found that the dynamics of dry port evolution is not yet explored. Thus, the development of the layout, services offered and involved actors of dry ports in Småland, Sweden have to be studied. Purpose:  The purpose for this report seeks to reveal how dry ports have evolved from establishment, in the area around Jönköping, and to discover in what form the dry ports can operate and compete. The study was based on the dynamics of three elements: layout, value added services and networks. Theory:  In the theoretical research the dry port concept is described. Due to the variety of descriptions, authors formed a definition for the thesis to clarify the content. Further, the literature analysis contained the characteristics, classifications and reasons of development as well as involved actors, advantages and disadvantages, location, layout, design and performance measurements. Method: The case study method was chosen to cover the identified gap. This qualitative study with semi-structured interviews conducted face-to-face and by telephone was accomplished with fourteen experts. If the authors faced problems regarding phone interviewees, open questions were prepared and sent to the respondent via email. The data gathering phase was followed by the analysis after which the conclusions were drawn. Conclusion:   The thesis proves that the development of dry ports is affected by a large number of internal and external factors. Terminals need to execute a thorough analysis of the market and the location in which they plan to operate. Therefore, the market has to be analysed continuously in order to keep improving their networks and value added services. Furthermore, the layout has to be adjusted for the changes and measurements have to be performed in order to increase the efficiency.
4

Avaliação econômica e energética de alternativas de transportes do etanol destinado à exportação na região Centro-Sul / Economic and energy evaluation of alternative transport ethanol for export in the Central-South

Nicola, Andrea Oliveira 10 December 2014 (has links)
O crescente interesse por fontes alternativas de energia, sobretudo por aquelas que consigam mitigar as emissões de gases causadores do efeito estufa (GEE), tem feito com que a produção de biocombustíveis aumentasse significativamente. Neste cenário o etanol produzido a partir da cana de açúcar, tem apresentado vantagem em relação a outros biocombustíveis, uma vez que a energia produzida é relativamente alta quando comparada com a consumida em seu processo produtivo. Neste contexto, as exportações brasileiras, principalmente as da região Centro-Sul, tentam suprir as necessidades mundiais através da produção excedente de etanol no país. No entanto, há gargalos logísticos na distribuição deste produto e isso tem feito que o transporte rodoviário fosse excessivamente utilizado na movimentação do etanol desde a usina até o porto. Diante destes aspectos, esta pesquisa busca investigar alternativas intermodais para a movimentação do etanol destinado à exportação, considerando a viabilidade econômica e energética empregada na cadeia logística deste biocombustível. Para isso, foram gerados quatro cenários utilizando os modos rodoviário, ferroviário, dutoviário e hidroviário. Através dos resultados obtidos, o cenário rodo-ferroviário apresentou uma estimativa de custo da ordem de R$ 654 milhões, valor da mesma ordem de grandeza do cenário rodoviário de referência, que foi de R$ 653 milhões. Já os cenários rodo-dutoviário e rodo-hidro-dutoviário, apresentaram custos maiores, respectivamente da ordem de R$ 661 milhões e R$ 674 milhões respectivamente. Em contrapartida, na análise de mínimo consumo energético o cenário rodo-hidro-dutoviário apresentou um gasto de energia da ordem de 533 mil MJ, cerca de 60% a menos que o consumido no cenário rodoviário, estimado em 1,45 milhões de MJ. Para o cenário rodo-dutoviário obteve-se uma estimativa de 680 mil MJ e para o cenário rodo-ferroviário de 764 mil MJ. Em relação ao porto de destino, São Sebastião foi o que apresentou sistematicamente, a melhor opção para quase todos os cenários analisados. / The growing interest in alternative energy sources, especially for those who can mitigate the emissions of gases causing the greenhouse gases (GHG), has made the production of biofuels increased significantly. In this scenario the ethanol produced from cane sugar, has shown advantages over other biofuels, since the energy generated is relatively high when compared with the consumed in the production process. In this context, brazilian exports, especially the South-Central region, try to supply the global requirements through ethanol production surplus in the country. However, there are logistical bottlenecks in the distribution of this product and it has done that the road transport were excessively used in the ethanol transportation from the plant to the port. Considering these aspects, this research seeks to investigate alternatives to the intermodal transportation of ethanol for export, considering the economic viability and energy used in this biofuel chain logistics. For this, four scenarios were generated using road, rail, pipeline and waterway modes. From the results obtained, the road-rail scenario presented an estimated cost of R$ 654 million, the same order of magnitude of road reference scenario, which was R$ 653 million. Already, the scenarios road-pipeline and road-hydro-pipeline, had higher costs respectively in the order of R$ 661 million and R$ 674 million respectively. In contrast, the analysis of minimum energy consumption the road-hydro-pipeline scenario presented an energy expenditure of approximately 533 thousand MJ, about 60% unless consumed in road scenario, estimated at 1.45 million MJ. For road-pipeline scenario yielded an estimate of 680 thousand MJ and the road-rail scenario of 764 thousand MJ. In relation to the port of destination, São Sebastião was systematically presented, the best option for almost all scenarios analyzed.
5

Avaliação econômica e energética de alternativas de transportes do etanol destinado à exportação na região Centro-Sul / Economic and energy evaluation of alternative transport ethanol for export in the Central-South

Andrea Oliveira Nicola 10 December 2014 (has links)
O crescente interesse por fontes alternativas de energia, sobretudo por aquelas que consigam mitigar as emissões de gases causadores do efeito estufa (GEE), tem feito com que a produção de biocombustíveis aumentasse significativamente. Neste cenário o etanol produzido a partir da cana de açúcar, tem apresentado vantagem em relação a outros biocombustíveis, uma vez que a energia produzida é relativamente alta quando comparada com a consumida em seu processo produtivo. Neste contexto, as exportações brasileiras, principalmente as da região Centro-Sul, tentam suprir as necessidades mundiais através da produção excedente de etanol no país. No entanto, há gargalos logísticos na distribuição deste produto e isso tem feito que o transporte rodoviário fosse excessivamente utilizado na movimentação do etanol desde a usina até o porto. Diante destes aspectos, esta pesquisa busca investigar alternativas intermodais para a movimentação do etanol destinado à exportação, considerando a viabilidade econômica e energética empregada na cadeia logística deste biocombustível. Para isso, foram gerados quatro cenários utilizando os modos rodoviário, ferroviário, dutoviário e hidroviário. Através dos resultados obtidos, o cenário rodo-ferroviário apresentou uma estimativa de custo da ordem de R$ 654 milhões, valor da mesma ordem de grandeza do cenário rodoviário de referência, que foi de R$ 653 milhões. Já os cenários rodo-dutoviário e rodo-hidro-dutoviário, apresentaram custos maiores, respectivamente da ordem de R$ 661 milhões e R$ 674 milhões respectivamente. Em contrapartida, na análise de mínimo consumo energético o cenário rodo-hidro-dutoviário apresentou um gasto de energia da ordem de 533 mil MJ, cerca de 60% a menos que o consumido no cenário rodoviário, estimado em 1,45 milhões de MJ. Para o cenário rodo-dutoviário obteve-se uma estimativa de 680 mil MJ e para o cenário rodo-ferroviário de 764 mil MJ. Em relação ao porto de destino, São Sebastião foi o que apresentou sistematicamente, a melhor opção para quase todos os cenários analisados. / The growing interest in alternative energy sources, especially for those who can mitigate the emissions of gases causing the greenhouse gases (GHG), has made the production of biofuels increased significantly. In this scenario the ethanol produced from cane sugar, has shown advantages over other biofuels, since the energy generated is relatively high when compared with the consumed in the production process. In this context, brazilian exports, especially the South-Central region, try to supply the global requirements through ethanol production surplus in the country. However, there are logistical bottlenecks in the distribution of this product and it has done that the road transport were excessively used in the ethanol transportation from the plant to the port. Considering these aspects, this research seeks to investigate alternatives to the intermodal transportation of ethanol for export, considering the economic viability and energy used in this biofuel chain logistics. For this, four scenarios were generated using road, rail, pipeline and waterway modes. From the results obtained, the road-rail scenario presented an estimated cost of R$ 654 million, the same order of magnitude of road reference scenario, which was R$ 653 million. Already, the scenarios road-pipeline and road-hydro-pipeline, had higher costs respectively in the order of R$ 661 million and R$ 674 million respectively. In contrast, the analysis of minimum energy consumption the road-hydro-pipeline scenario presented an energy expenditure of approximately 533 thousand MJ, about 60% unless consumed in road scenario, estimated at 1.45 million MJ. For road-pipeline scenario yielded an estimate of 680 thousand MJ and the road-rail scenario of 764 thousand MJ. In relation to the port of destination, São Sebastião was systematically presented, the best option for almost all scenarios analyzed.
6

Green intermodal freight transportation: bi-objective modelling and analysis

Demir, Emrah, Hrusovsky, Martin, Jammernegg, Werner, Van Woensel, Tom January 2019 (has links) (PDF)
Efficient planning of freight transportation requires a comprehensive look at wide range of factors in the operation and man- agement of any transportation mode to achieve safe, fast, and environmentally suitable movement of goods. In this regard, a combination of transportation modes offers flexible and environmentally friendly alternatives to transport high volumes of goods over long distances. In order to reflect the advantages of each transportation mode, it is the challenge to develop models and algorithms in Transport Management System software packages. This paper discusses the principles of green logistics required in designing such models and algorithms which truly represent multiple modes and their characteristics. Thus, this research provides a unique practical contribution to green logistics literature by advancing our understanding of the multi-objective planning in intermodal freight transportation. Analysis based on a case study from hinterland intermodal transportation in Europe is therefore intended to make contributions to the literature about the potential benefits from com bining economic and environmental criteria in transportation planning. An insight derived from the experiments conducted shows that there is no need to greatly compromise on transportation costs in order to achieve a significant reduction in carbon-related emissions.
7

The international networking between European logistical operators

Ludvigsen, Johanna January 2000 (has links)
This thesis explores the temporal development of a strategic alliance formed by seven logistical firms from the Nordic region and European mainland. The analytical spotlight focuses on a decade long transition from a loose collaborative association to a formal consortium. By applying five levels of analysis, the study produced several insights and contributions of conceptual, theoretical, analytical and managerial art. Conceptually, the explanatory viability of several theories has been verified while conceptual inadequacy of several other propositions have been established. Theoretically, the study bridges the network-based conceptualizations of strategic alliances with other scientific fields such as international management, business process redesign, logistical systems evolution, intercultural communication and cross-cultural decision-making, and integrates research outcomes into an empirically validated model of the alliance’s systemic fit. Analytically, the "black box" of alliance’s evolution has been unpacked using a longitudinal, multivariate research method. By identifying several inversely related causal motors that concurrently and interchangeably shaped the alliance transition, the study demonstrates that over a ten-year period the forces of collaboration overpowered the relational and cultural diversity, and contributed to intra-alliance match. Managerial relevance derives from the fact that the alliance became Pan-European logistical service supplier, benefited from network enlargement, realized economies of scope, higher customer density, joint operational governance and intimate knowledge of demand specifics. These inputs have been translated into discernible competitive advantage by both, the multi-domestic and transnational output supply strategies that seldom are employed in parallel by orthodox corporate systems. The multi-domestic style of operations allowed the alliance partners creating a complete value chain in their home markets. This enabled the alliance to cope with demand heterogeneity in the European market and compete with other internationals through a broad market-service spectrum. On the other hand, by producing different elements of its value chain in different countries, the alliance created a transnational distribution system that could serve global customers, realize economies of international standardization and participate in global rivalry. By showing that single-modal freight supply solutions should be customized to meet international demand diversity, while intermodal distribution measures should be standardized to secure uniform quality standard throughout the entire distribution channel, these findings provided empirically tested knowledge on viable scope of integration for operators in complex international markets. These latter insights may represent valuable utility to managers seeking to match the supply structure with demand postulates from international users. / Diss. Stockholm : Handelshögsk., 2001
8

Optimisation des problèmes de transport multimodal / Optimization of multimodal transportation problems

Oudani, Mustapha 21 May 2016 (has links)
Cette thèse est une contribution aux travaux de recherche sur l’optimisation des problèmes du transport multimodal. Les principaux concepts clé de la multimodalité dans les réseaux du transport intermodal et l’état de l’art des travaux scientifique du domaine y sont présentés. Le problème de la localisation des terminaux du transport combiné est ensuite étudié. Nous proposons un algorithme génétique à codage mixte pour la résolution de ce problème et nous comparons nos résultats avec ceux de la littérature. Un ensemble de problèmes posés dans le cadre de notre travail sur le projet DCAS (Direct Cargo Axe Seine), porté par le Grand Port Maritime du Havre, y est décrit et modélisé par des outils de programmation mathématique. Ainsi, nous avons étudié le problème du transfert de navettes ferroviaires qui consiste à optimiser le transfert d’un ensemble de conteneurs entre des terminaux maritimes et un terminal multimodal. Ensuite, nous avons modélisé le problème d’ordonnancement des trains de grandes de lignes pour le placement sur les voies de la cour ferroviaire du terminal multimodal du Havre. Ces problèmes sont résolus en utilisant une approche combinée optimisation-simulation. Une première application est basée sur un algorithme génétique couplé avec la simulation multi agents pour l’affectation des voies aux trains. Une deuxième, consiste à optimiser la manutention des conteneurs lors d’un transbordement rail-rail en utilisant un algorithme de colonie de fourmis intégré dans le modèle de simulation et une stratégie de collaboration agents pour minimiser les temps d’attente des portiques et ainsi augmenter leurs productivités. / This thesis is a contribution to research on the optimization of multimodal transport problems. The main key concepts of multimodality in the intermodal transportation networks and the state of the art of scientific works in the field are presented. The intermodal terminal location problem is then studied. We propose a genetic algorithm with mixed encoding for solving this problem and we compare our results with those of literature. A set of problems in the framework of our work on the project DCAS (Direct Cargo Axe Seine), carried by the Grand Port Maritime du Havre, are described and modeled by mathematical programming tools. Thus, we studied the problem of the transfer of rail shuttles which is to optimize the transfer of a set of containers between maritime terminals and a multimodal terminal. We then modeled the scheduling problem of freight trains for placement on rail tracks. These problems are solved by using combined optimization simulation approaches. A first application is based on a genetic algorithm coupled with the multi agent’s simulation. A second is to optimize a rail-rail transshipment of containers using an ant colony algorithm embedded in the simulation model and an agent’s collaboration strategy to minimize waiting times and increase cranes productivity.541 ##‎$a@Optimization of multimodal transportation problems
9

Skládací kontejnery a jejich využití v intermodální přepravě / Foldable Containers and their utilization in Intermodal Transport

Pernikář, Jan January 2013 (has links)
The aim of the thesis is to characterize the folding containers as one of the potential solutions to the problem of the repositioning of empty containers and to evaluate the possibility of their practical use in intermodal transport. The theoretical part characterizes contemporary development in international trade, intermodal transportation, the issue of empty containers and also characterizes foldable containers together with the assumptions of their successful introduction to the market. The practical part deals with current concepts of foldable containers, there is also an example for comparing the costs of transport when using standard or foldable containers and the opinion of a representative of one of the leading shipping companies on use foldable containers in practice. To obtain information used in the practical part of the thesis a secondary research was carried out, where most information comes from research papers and websites, and also primary research was done in the form of an interview with a representative of the shipping company. In conclusion is the evaluation of the possibility of using foldable containers in practice which is based on the information obtained through research.
10

Stabilizace trhu námořní kontejnerové přepravy v kontextu České republiky / Container Transportation by Sea

Kamlar, Petr January 2008 (has links)
Container Transportation by Sea

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