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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

Avaliação técnico-econômica das principais tendências e alternativas do transporte rodoviário nacional sob o ponto de vista energético e ambiental / Technical economical evaluation of the main tendencies and alternatives of the Brazilian on-road transportation under energy and environmental perspectives

Figueiredo, Silvio de Andrade 21 October 2013 (has links)
Ferramentas computacionais, baseadas em modelos de inventários, que consigam predizer, com precisão apropriada, o consumo de combustíveis e as emissões veiculares, principais motivadores do desenvolvimento automotivo atual, são fundamentais para a elaboração de políticas públicas eficazes vinculadas a essas questões. No Brasil, apesar de afetarem significativamente a sociedade, muitas das intervenções governamentais nesse segmento são realizadas sem a adequada avaliação de seus impactos. Isso ocorre ou porque a importância dessas ferramentas nem sempre é reconhecida ou por não se ter ferramentas apropriadas. O objetivo deste trabalho foi o de desenvolver uma ferramenta de prognóstico do consumo de combustíveis e das emissões da frota rodoviária, estatisticamente consistente, que pudesse ser utilizada para esse propósito. Para tanto, inicialmente buscou-se identificar os aspectos relacionados às questões que deveriam ser considerados nesse desenvolvimento, por meio do levantamento das tendências evolutivas e alternativas que estão sendo apresentadas relativas a combustíveis, tecnologia veicular e sistemas de transportes. A seguir foram revistos os principais modelos e ferramentas públicos, nacionais e estrangeiros, dessa natureza. E, diante da constatação que eles não poderiam ser empregados, apesar dos limites impostos pela disponibilidade de dados, foi proposta uma nova abordagem para se atingir esse objetivo. Primeiro foi desenvolvido um conjunto de planilhas integrando todos os dados e cálculos de um modelo bottom-up similar ao utilizado nos inventários de emissões tóxicas nacionais, totalmente interconectado e configurado para facilitar, por meio de um processo iterativo, o ajuste fino das estimativas mais incertas, de forma que os consumos totalizados resultantes do modelo coincidissem tanto quanto possível com os consumos observados no país. A seguir, foram desenvolvidos modelos econométricos, para estimar os consumos totalizados de combustíveis a partir de indicadores econômicos pertinentes. E pela inserção desses modelos econométricos no modelo bottom-up anterior, foi gerado um modelo híbrido que permite inventariar e prognosticar, segregadas por classes, o consumo de combustíveis e as emissões veiculares. Os consumos de combustíveis obtidos por meio desses modelos, quando comparados com valores observados, forneceram resultados estatisticamente robustos, que podem ser, em algumas condições, convertidos na emissão de CO2. O mesmo não é possível afirmar com relação às demais emissões, inclusive em função da dificuldade de vincular as fontes emissoras a indicadores de qualidade do ar, o que não invalida o uso do modelo híbrido para obtenção de resultados comparativos. Finalmente, os modelos foram submetidos a análise sensibilidade e sua aplicabilidade foi verificada para alguns cenários. / Computational tools, based on inventory models, which are able to predict, with the appropriated accuracy, vehicular fuel consumption and emissions, main current drivers of the automotive development, are essentials for the development of effective public policies related to these issues. In Brazil, despite their significantly influence over the society, many government interventions in this segment are undertaken without the adequate assessment of their impacts. This happen because the importance of these tools is not always recognized or because proper tools are not available. The goal of this study was to develop a statistically consistent prognostic tool of road fuel consumption and emissions, which could be used for this purpose. Initially, by surveying the evolutionary trends and known alternatives related to fuels, vehicular technology and transportation systems, it was examined all the aspects that should be considered for this work. Next it was reviewed the main domestic and foreign public models and tools of this sector. Realizing that they could not be used, due to the limits imposed by data availability, it is proposed a new approach to achieve this goal. First it is developed a set of worksheets integrating all data and calculations of a bottom-up model, similar to the ones used in national inventories of toxic emissions. The set was interconnected and configured to facilitate, through an iterative process, the fine tuning of the uncertain estimates, in such way that the model total consumptions as much as possible reproduce the fuel consumptions observed in the country. Next econometric models were developed to estimate total fuel consumptions based on identified relevant economic indicators. And inserting these econometric models in the previous bottom-up model, it was generated a hybrid model that allows inventorying and forecasting of fuel consumptions and vehicular emissions segregated by classes. When compared with the observed fuel consumptions, these models presented statistically robust results. Under some conditions, these results can be converted in CO2 emissions. The same cannot be said with respect to other emissions, partially due to the difficulty to link emission sources to air quality measurements, which does not invalidate the use of the hybrid model to obtain comparative results for these emissions. Finally, the models were submitted to a sensitivity analysis and their applicability was verified for some scenarios.
102

Power infrastructure requirements for road transport electrification

Nicolaides, Doros January 2018 (has links)
Deep decarbonisation of road transportation is challenging. One of the most potentially beneficial approaches is electrification which is the subject of this PhD thesis. A widespread penetration of electric vehicles (EVs) across a large proportion of road transport demand is needed to realise the benefits of an electrified transport sector. However, this is dependent on overcoming significant barriers. This study performs a systematic analysis of how proven power charging technologies could be used to unlock the barriers to widespread electrification of road transportation. Various road transport sectors and type of journeys are explored including aspects of autonomous operations and novel wireless power transfer technologies. For each operation, a framework is proposed that allows the exploitation of current and potential future electrification technologies to enable shifting towards EVs. Based on that, simulation tools and methods are developed to calculate the power requirements of EVs and determine a suitable charging infrastructure. The additional power demand, electric load and the implications for the electricity supply network are explored. The total expenditure needed and the CO2 emission savings are also calculated for each investigated operation. Transitional strategies include the electrification of bus routes, refuse collection functions, home deliveries and aspects of autonomous operations for public transportation within the boundaries of the cities. In the long-term, focus is given on passenger cars and freight vehicles for both urban and inter-urban journeys. A nationwide adoption of all electrification strategies proposed in this thesis would increase the peak power demand of Great Britain by approximately 38 GW (72% of the current peak) and the electricity consumption by 180 TWh per year (45% of current consumption). The total capital cost required is calculated at £225 billion which is similar to the cost of other large infrastructure projects of the country. The impact would be a significant aggregate saving of approximately 2,000 MtCO2 between the numbers calculated for today's norms (2018) and those calculated for 2050.
103

Nutzungsmöglichkeiten von Floating Car Data zur Verkehrsflussoptimierung

Körner, Matthias 13 August 2012 (has links) (PDF)
Floating Car Data (FCD) besitzen eine sehr breite Palette an Anwendungsmöglichkeiten, die aber teilweise noch keine massenhafte Verbreitung gefunden haben, auch wenn das Innovationspotenzial als sehr hoch eingeschätzt wird. Dies begründet sich in erster Linie durch die meist relativ großen Erfassungsintervalle bei der derzeitigen FCD-Erfassung. In Dresden ist ein Taxi-FCD-System in Betrieb, welches sich durch eine sehr hohe Detektionsdichte auszeichnet. Die Fahrzeugpositionen werden mindestens alle 5 Sekunden aufgezeichnet. Damit bestehen ausgezeichnete Möglichkeiten, mögliche Mehrwerte zu prüfen und Prototypen zu etablieren. Getestet wurde u. a. die Generierung von Straßennetzabbildern. Im Dauerbetrieb befindet sich die FCD-basierte Verkehrslageermittlung.
104

A Framework to Measure the Socio-Economic Impact of Development Programs Using Malmquist Index

Devaraj, H January 2015 (has links) (PDF)
The main objective of this research is to evaluate the socio economic impact of the development programs like MGNREGA, JnNURM and development of Roads project, on the intended target area. The entire thesis can be divided in to two parts; (1) developing method to evaluate the socio economic impact assessment and (2) case studies. Two different techniques were used to evaluate the change in the productivity. Initially the change is measure by calculating the difference in the efficiencies between two time period using base period and current period production technologies. To illustrate this method a case study of MGNREGA has been considered to evaluate the impact of seventeen districts of the country. From the results it is found that there is difficult in comparing the two efficiencies due to the scaling issue of two production technologies. Further Data Envelopment Analysis is used to evaluate the distance function in the calculation of Malmquist index (MI). MI gives the productivity change between two time periods and is calculated as the geometric mean of two ratios measured with reference to the time period and time period respectively. A new approach is presented by interpreting the two ratios of MI separately using the distance functions to identify the productivity change between two time periods. Three different regions were identified to determine the productivity change; improvement region which observe improvement in the productivity between two time periods, deterioration region which indicate deterioration in the productivity and status quo region suggesting the stagnation region. Two case studies i.e. Bangalore Metropolitan Transport Corporation and development of roads under the name “5054-Decongestion of Roads project” were considered. The impact of Jawaharlal Nehru National Urban Renewal Mission (JnNURM) funds on the performance of Bangalore Metropolitan Transport Corporation (BMTC) is studied using the proposed method. The results suggest that for 50 percent of the overall productivity have improved due to the intervention. The deterioration is mainly because of the addition input surplus in terms of number of buses and output slack in terms of reduced load factor, effective distance travelled, operational costs and increase in number of breakdown and accident rates for these DMU’s. The socio economic impact of the roads developed by Government of Karnataka under the name of “5054-Decongestion of Roads project” in and around Bangalore was also studied using this method and the results shows that out of five DMU’s four DMU’s show improvement in the productivity.
105

Avaliação técnico-econômica das principais tendências e alternativas do transporte rodoviário nacional sob o ponto de vista energético e ambiental / Technical economical evaluation of the main tendencies and alternatives of the Brazilian on-road transportation under energy and environmental perspectives

Silvio de Andrade Figueiredo 21 October 2013 (has links)
Ferramentas computacionais, baseadas em modelos de inventários, que consigam predizer, com precisão apropriada, o consumo de combustíveis e as emissões veiculares, principais motivadores do desenvolvimento automotivo atual, são fundamentais para a elaboração de políticas públicas eficazes vinculadas a essas questões. No Brasil, apesar de afetarem significativamente a sociedade, muitas das intervenções governamentais nesse segmento são realizadas sem a adequada avaliação de seus impactos. Isso ocorre ou porque a importância dessas ferramentas nem sempre é reconhecida ou por não se ter ferramentas apropriadas. O objetivo deste trabalho foi o de desenvolver uma ferramenta de prognóstico do consumo de combustíveis e das emissões da frota rodoviária, estatisticamente consistente, que pudesse ser utilizada para esse propósito. Para tanto, inicialmente buscou-se identificar os aspectos relacionados às questões que deveriam ser considerados nesse desenvolvimento, por meio do levantamento das tendências evolutivas e alternativas que estão sendo apresentadas relativas a combustíveis, tecnologia veicular e sistemas de transportes. A seguir foram revistos os principais modelos e ferramentas públicos, nacionais e estrangeiros, dessa natureza. E, diante da constatação que eles não poderiam ser empregados, apesar dos limites impostos pela disponibilidade de dados, foi proposta uma nova abordagem para se atingir esse objetivo. Primeiro foi desenvolvido um conjunto de planilhas integrando todos os dados e cálculos de um modelo bottom-up similar ao utilizado nos inventários de emissões tóxicas nacionais, totalmente interconectado e configurado para facilitar, por meio de um processo iterativo, o ajuste fino das estimativas mais incertas, de forma que os consumos totalizados resultantes do modelo coincidissem tanto quanto possível com os consumos observados no país. A seguir, foram desenvolvidos modelos econométricos, para estimar os consumos totalizados de combustíveis a partir de indicadores econômicos pertinentes. E pela inserção desses modelos econométricos no modelo bottom-up anterior, foi gerado um modelo híbrido que permite inventariar e prognosticar, segregadas por classes, o consumo de combustíveis e as emissões veiculares. Os consumos de combustíveis obtidos por meio desses modelos, quando comparados com valores observados, forneceram resultados estatisticamente robustos, que podem ser, em algumas condições, convertidos na emissão de CO2. O mesmo não é possível afirmar com relação às demais emissões, inclusive em função da dificuldade de vincular as fontes emissoras a indicadores de qualidade do ar, o que não invalida o uso do modelo híbrido para obtenção de resultados comparativos. Finalmente, os modelos foram submetidos a análise sensibilidade e sua aplicabilidade foi verificada para alguns cenários. / Computational tools, based on inventory models, which are able to predict, with the appropriated accuracy, vehicular fuel consumption and emissions, main current drivers of the automotive development, are essentials for the development of effective public policies related to these issues. In Brazil, despite their significantly influence over the society, many government interventions in this segment are undertaken without the adequate assessment of their impacts. This happen because the importance of these tools is not always recognized or because proper tools are not available. The goal of this study was to develop a statistically consistent prognostic tool of road fuel consumption and emissions, which could be used for this purpose. Initially, by surveying the evolutionary trends and known alternatives related to fuels, vehicular technology and transportation systems, it was examined all the aspects that should be considered for this work. Next it was reviewed the main domestic and foreign public models and tools of this sector. Realizing that they could not be used, due to the limits imposed by data availability, it is proposed a new approach to achieve this goal. First it is developed a set of worksheets integrating all data and calculations of a bottom-up model, similar to the ones used in national inventories of toxic emissions. The set was interconnected and configured to facilitate, through an iterative process, the fine tuning of the uncertain estimates, in such way that the model total consumptions as much as possible reproduce the fuel consumptions observed in the country. Next econometric models were developed to estimate total fuel consumptions based on identified relevant economic indicators. And inserting these econometric models in the previous bottom-up model, it was generated a hybrid model that allows inventorying and forecasting of fuel consumptions and vehicular emissions segregated by classes. When compared with the observed fuel consumptions, these models presented statistically robust results. Under some conditions, these results can be converted in CO2 emissions. The same cannot be said with respect to other emissions, partially due to the difficulty to link emission sources to air quality measurements, which does not invalidate the use of the hybrid model to obtain comparative results for these emissions. Finally, the models were submitted to a sensitivity analysis and their applicability was verified for some scenarios.
106

Advanced Simulation Methodologies For Crashworthiness And Occupant Safety Assessment Of An Indian Railways Passenger Coach

Prabhune, Prajakta Vinayak 07 1900 (has links) (PDF)
Accidents involving passenger trains happen regularly in India. The reasons for such accidents could be many; such as weather and flooding, faulty tracks, bridge collapse, collisions caused by signaling errors, mechanical failures, driver error, sabotage etc. The annual accident-related deaths as a percentage of the total number of passengers carried by Indian Railway may seem to be negligible, but the aim should be to achieve zero fatality as every single person killed is an irreplaceable loss to his/her family. It needs to be mentioned that in addition to fatalities for which exact numbers are not available, serious injuries and permanent disabilities caused by train accidents in India at present stand completely unaccounted for. In the absence of a large scale renovation and crash avoidance measures coupled with the propensity to increase the number of trains every year, enhancing passive safety is crucial i.e. crashworthiness and occupant safety of passenger coaches of Indian trains. In the current work, crashworthiness and occupant safety of the existing typical three-tier cabin passenger coach of Indian Railway in an event of collision accident are assessed with the aid of a finite element analysis. In the light of the published work on research in railroad equipment crashworthiness, the current work is intended to envisage the methodology to assess the Indian Railway passenger coach from the point of view of the crashworthiness and occupant safety using CAE (Computer aided engineering) based approach. It is involved with an extensive study of the structural crush behavior of an individual passenger coach car and its effect on the interaction between occupants and the coach interior. Here the structural crush behavior of a typical three-tier cabin passenger coach is evaluated for the head-on impact against a fixed and rigid barrier. The occupant response for the same scenario is also studied which can be viewed as a component of the actual occupant response due to the structural crush behavior of the passenger coach. This can give useful estimates of injury severity and fatalities that may occur in actual accidents. An FE model of the passenger coach structure was built and validated using International Railway Union (UIC) specified code OR 567-design requirements in terms of static loads constituting structural proof cases. These proof cases specify the static load values the coach body structure should withstand without any permanent deformation or failure when applied at the specified locations on the structural ends across the longitudinal axis. In addition, a favorable correlation between the simulation and actual experiment for drop impact behavior of the open section specimens, namely C-section and I-section, was obtained to validate the simulation methodology. LS-DYNA a nonlinear dynamic explicit FE solver was used to carry out all the dynamic impact simulations involved in the current work. The material modeling takes into account the strain rate effect which is essential for the material impact behavior study. The contact modeling was done using penalty contact method. The degrading effect of the buffer on the structural crush patterns which induced the undesirable global bending and jackknifing of the whole coach structure was demonstrated with the help of dynamic impact simulations of the coach structure. The quantification of occupant injury was done by occupant safety simulations using the Hybrid III 50th percentile male dummy FE model. The dummy having been designed for simulating automobile accident scenarios, its contacts had to be adapted to suit the excessive mobility conditions in the coach interior. The dummy was revalidated successfully for the head drop test, pendulum chest impact test, neck flexion and extension test and knee impact test. Impact simulations for three different speeds were performed by positioning the dummy close to the impact point. Injury criteria such as Head Injury Criterion, Chest Deceleration, Knee force level and Neck extension-flexion moments were used to estimate the injury severity level and fatality rate.
107

Pracovní podmínky řidičů v MKD / Working conditions of drivers in the international transport

Fronk, Tomáš January 2009 (has links)
The main aim of the thesis is a comlex description and explanation of legislative concernig the working conditions of drivers in branch of international transport. It provides the reader general overview of the whole field including function of the digital tachograph system and current development of EU legislative. In the practical part, there are described some actual problems, which occur in this area - it's especially the question of road controls and fines. The opinions of drivers concernig this matter are included as well.
108

Mýtný systém Itálie / Italy toll system

Šmíd, Milan January 2010 (has links)
The toll system selected countries, taxes of road transport in Italy, legislation, used technology, compatibility, taxes of vehicles, repair and system organization, next fiscal arrangements in the area road transport, payment methods, Telepass, contractual and technical interoperability.
109

Doprava v EU: současné trendy v železniční a silniční dopravě / EU Transport: current trends of rail and road transport

Šuhajová, Martina January 2013 (has links)
This thesis is devoted to the EU Common transport policy with a focus on rail and road transport. The first chapter briefly describes the historical development of transport and ultimately defines its basic concepts. The following chapter is exclusively focused on the basic characteristics of the critical areas of selected transport sectors, which in the context of the integration of European transport systems play a crucial role. The third chapter deals with the characteristics of three Transport White Papers and defines the objectives of the Common Transport Policy and TEN-T policy. Another part deals with the Trans-European transport network and the evaluation of the success of the construction of TEN-T. The last chapter analyzes the success of the objectives of the EU Common Transport Policy defined in the third chapter.
110

Určení zdrojů rizik při přepravě nebezpečných látek na silnicích a návrh opatření na snížení ztrát a škod na veřejných aktivech / Identifying the Sources of Risk Related to Road Transport of Hazardous Substances and a Proposal of Measures for Reducing Losses on Public Assets

Poul, Adam January 2020 (has links)
The master‘s thesis focuses on the risks of transporting dangerous goods by road. The introductory part deals with related legislation of the Czech Republic is analyzed, followed by international legislation. In the European Union, the transport of dangerous goods is regulated primarily by the European agreement concerning the International carriage of dangerous goods by road (ADR). Between 2002 and 2019, master‘s thesis analyzes and describes the statistics of traffic accidents with the presence of dangerous goods. Furthermore, this master‘s thesis also analyzes the characteristics of the sources of traffic accident risks, and when activating the risk, the possible effects of traffic accidents and subsequent leakage of dangerous goods are described. In fulfilling the aims of the master‘s thesis, agreement was found in the causes of traffic accidents in statistics and in the literature in the fact that in 80% it is the fault of the human factor. Analysis of a set of 10 large accidents with the presence of dangerous goods using a modified "What, if" method identified impacts on public assets. Based on these identified impacts, measures were proposed that would be appropriate to apply in the public interest.

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