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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.
81

Improving Analytical Travel Time Estimation for Transportation Planning Models

Lu, Chenxi 19 May 2010 (has links)
This dissertation aimed to improve travel time estimation for the purpose of transportation planning by developing a travel time estimation method that incorporates the effects of signal timing plans, which were difficult to consider in planning models. For this purpose, an analytical model has been developed. The model parameters were calibrated based on data from CORSIM microscopic simulation, with signal timing plans optimized using the TRANSYT-7F software. Independent variables in the model are link length, free-flow speed, and traffic volumes from the competing turning movements. The developed model has three advantages compared to traditional link-based or node-based models. First, the model considers the influence of signal timing plans for a variety of traffic volume combinations without requiring signal timing information as input. Second, the model describes the non-uniform spatial distribution of delay along a link, this being able to estimate the impacts of queues at different upstream locations of an intersection and attribute delays to a subject link and upstream link. Third, the model shows promise of improving the accuracy of travel time prediction. The mean absolute percentage error (MAPE) of the model is 13% for a set of field data from Minnesota Department of Transportation (MDOT); this is close to the MAPE of uniform delay in the HCM 2000 method (11%). The HCM is the industrial accepted analytical model in the existing literature, but it requires signal timing information as input for calculating delays. The developed model also outperforms the HCM 2000 method for a set of Miami-Dade County data that represent congested traffic conditions, with a MAPE of 29%, compared to 31% of the HCM 2000 method. The advantages of the proposed model make it feasible for application to a large network without the burden of signal timing input, while improving the accuracy of travel time estimation. An assignment model with the developed travel time estimation method has been implemented in a South Florida planning model, which improved assignment results.
82

Ktoré faktory sú zodpovedné za rast dopytu po leteckej preprave pasažierov? / Which Factors Drive Growth of Demand for Passenger Air Travelling?

Ondrejová, Zuzana January 2015 (has links)
Is GDP per capita one of the main drivers affecting demand for passenger air travelling? Based on the time series analysis conducted for North American and Middle Eastern region, we have not rejected hypothesis about positive impact of GDP per capita on demand for air travelling. The thesis also analyzes whether the effects observed are weaker for more developed and more saturated markets. The second hypothesis was rejected, as we have found that the effect of the GDP per capita was on average 10% stronger for the North American region than for the Middle Eastern region. Moreover, we have found that for both regions oil prices are the important driver of the passenger air travel demand.
83

An initial implementation of a multi-agent transport simulator for South Africa

Fourie, P.J. (Pieter Jacobus) 24 June 2009 (has links)
Transport demand planning in South Africa is a neglected field of study, using obsolete methods to model an extremely complex, dynamic system composed of an eclectic mix of First and Third World transport technologies, infrastructure and economic participants. We identify agent-based simulation as a viable modelling paradigm capable of capturing the effects emerging from the complex interactions within the South African transport system, and proceed to implement the Multi-Agent Transport Simulation Toolkit (MATSim) for South Africa's economically important Gauteng province. This report describes the procedure followed to transform household travel survey, census and Geographic Information System (GIS) data into an activity-based transport demand description, executed on network graphs derived from GIS shape files. We investigate the influence of network resolution on solution quality and simulation time, by preparing a full network representation and a small version, containing no street-level links. Then we compare the accuracy of our data-derived transport demand with a lower bound solution. Finally the simulation is tested for repeatability and convergence. Comparisons of simulated versus actual traffic counts on important road network links during the morning and afternoon rush hour peaks show a minimum mean relative error of less than 40%. Using the same metric, the small network differs from the full representation by a maximum of 2% during the morning peak hour, but the full network requires three times as much memory to execute, and takes 5.2 times longer to perform a single iteration. Our census- and travel survey-derived demand performs significantly better than uniformly distributed random pairings of home- and work locations, which we took to be analogous to a lower bound solution. The smallest difference in corresponding mean relative error between the two cases comes to more than 50%. We introduce a new counts ratio error metric that removes the bias present in traditional counts comparison error metrics. The new metric shows that the spread (standard deviation) of counts comparison values for the random demand is twice to three times as large as that of our reference case. The simulation proves highly repeatable for different seed values of the pseudo-random number generator. An extended simulation run reveals that full systematic relaxation requires 400 iterations. Departure time histograms show how agents 'learn' to gradually load the network while still complying with activity constraints. The initial implementation has already sparked further research. Current priorities are improving activity assignment, incorporating commercial traffic and public transport, and the development and implementation of the minibus taxi para-transit mode. Copyright / Dissertation (MEng)--University of Pretoria, 2009. / Industrial and Systems Engineering / unrestricted
84

Akzeptanz von Straßenbenutzungsgebühren: Entwicklung und Überprüfung eines Modells

Schade, Jens 27 October 2005 (has links)
Several research projects all over the world have considered transport pricing measures and policies as promising attempts to solve urgent traffic problems in urban areas. One important precondition for the successful implementation of pricing strategies is public acceptability. However, empirical findings have shown that the acceptability of such strategies in general is very low. Aim of this dissertation is to analyse the reasons for the low acceptability of road pricing. The dissertation is organized as follows: Firstly, the problems related to transport and the measures to cope with these problems are outlined. The focus is thereby on economic measures such as road user fees, whose economic and traffic-related assumptions are discussed. Then, a definition of the terms used is given and main European results concerning the current acceptability level of various travel demand management (TDM) strategies are reported. Moreover, a theoretical framework is developed which attempts to identify the essential factors determining transport pricing acceptability. In two empirical studies (N1 = 923, N2 = 667), it is investigated whether and to what extent these factors contribute to the explanation of acceptability. Finally, conclusions are drawn and some recommendations for future research are given. / Straßenbenutzungsgebühren für den privaten Autoverkehr sind vielfach als sinnvoll und wünschenswert vor allem zur Lösung der zahlreichen Verkehrsprobleme in städtischen Ballungsräumen begründet worden. Bisher ist es jedoch nicht zu einer nennenswerten Umsetzung dieser Maßnahmen gekommen. Es herrscht in der Literatur Einigkeit, daß die geringe Akzeptanz von Straßenbenutzungsgebühren in der Bevölkerung und die deutliche Ablehnung bei den betroffenen Autofahrern die wesentlichen Gründe für den fehlenden politischen Willen sind, road pricing einzuführen. Ziel dieser Arbeit war es, die Ursachen und Bedingungen für die mangelnde Akzeptanz von Straßenbenutzungsgebühren bei den betroffenen Autofahrern zu untersuchen. Die Arbeit ist wie folgt aufgebaut: Im ersten Abschnitt wird die Ausgangslage und der Problemhintergrund dargestellt. Es wird erläutert, welche negativen Konsequenzen des motorisierten Individualverkehrs vorliegen, und mit welchen Maßnahmen ihnen begegnet werden kann. Der Fokus liegt dabei auf preispolitischen Maßnahmen wie Straßenbenutzungsgebühren, dessen ökonomische und verkehrswissenschaftliche Annahmen dargestellt werden. Dem gegenübergestellt wird die gesellschaftspolitische Realität: zum einen in Form der massiven Ablehnung von Straßenbenutzungsgebühren durch Bevölkerung und betroffene Autofahrer und zum anderen in Form der zahlreichen, erfolglosen und gescheiterten Versuche, Straßenbenutzungsgebühren einzuführen. Dies mündet in die Ableitung erster Forschungsfragen und in die Entwicklung des Untersuchungsansatzes. Im darauf folgenden Abschnitt werden die theoretischen Grundlagen zur Untersuchung der Akzeptanz von Straßenbenutzungsgebühren gelegt. Dabei wird zunächst geklärt, wie sich der Begriff "Akzeptanz" definieren läßt und in welche relevanten psychologischen Theorien er sich einordnet. Im Anschluß wird das Modell zur Akzeptanz von Schlag vorgestellt und analysiert. Darauf aufbauend werden die zentralen Variablen des Modells auf ihre theoretische und empirische Relevanz und unter Berücksichtigung potentiell konkurrierender Ansätze dargestellt und untersucht. Ziel ist die Klärung der logischen und kausalen Struktur des Modells und der Beziehungen der Variablen untereinander. Dies führt schließlich in die Ableitung überprüfbarer Hypothesen in Form eines erweiterten Akzeptanzmodells. Zur Überprüfung des Modells, der aufgestellten Hypothesen und Forschungsfragen werden zwei Untersuchungen berichtet (N1 = 923, N2 = 667), die inhaltlich aufeinander aufbauen. Diese wurden im Rahmen der EU-Forschungsprojekte TransPrice und AFFORD durchgeführt. Generelles Ziel ist die Validierung der Modellkonstrukte und ihrer angenommenen Beziehungen. Im letzten Abschnitt werden zusammenfassend und basierend auf den beiden Studien die wesentlichen Ergebnisse rekapituliert, sowie offene Forschungsfragen und Anforderungen abgeleitet, die sich zukünftigen Studien stellen. Schließlich wird diskutiert, welche Implikationen sich aus dieser Untersuchung ziehen lassen und welche Aspekte zu berücksichtigen sind, wenn Straßenbenutzungsgebühren der Öffentlichkeit präsentiert werden. - Die Druckexemplare enthalten jeweils eine CD-ROM als Anlagenteil: 490 KB - Nutzung: Referat Informationsvermittlung der SLUB
85

Verkehrsnachfragemodellierung am Beispiel der Stadt Brandenburg an der Havel

Schwarz, Matthias 12 February 2018 (has links)
Das Thema der vorliegenden Bachelorarbeit ist, das Vier-Stufen-Modell der Verkehrsnachfrage nach Lohse, auch als Kennwertmodell bekannt, auf die Stadt Brandenburg an der Havel anzuwenden, um die Verkehrserzeugung, die Verkehrsverteilung und die Verkehrsmittelwahl zu berechnen. Dies ist für alle Leser interessant, die damit beginnen, sich mit der integrierten Verkehrsplanung zu beschäftigen, denn diese Arbeit stellt das theoretische, rechnerische und praktische Vorgehen formal vor. Die Berechnungen wurden mit dem Programm „Excel 2013“ realisiert. Zudem ist der Arbeit ein USB-Stick beigelegt, aus dem Sie die formalen Rechnungen aus der Bachelorarbeit besser nachvollziehen können, da auf dem USB-Stick alle Rechnungen hinterlegt sind, die dem Verfahren zugrunde liegen. Zusätzlich enthält der USB-Stick einige Grafiken, welche die Verteilung der Verkehrsmittel in der Stadt Brandenburg an der Havel darstellen.
86

The usage of location based big data and trip planning services for the estimation of a long-distance travel demand model. Predicting the impacts of a new high speed rail corridor

Llorca, Carlos, Ji, Joanna, Molloy, Joseph, Moeckel, Rolf 24 September 2020 (has links)
Travel demand models are a useful tool to assess transportation projects. Within travel demand, long-distance trips represent a significant amount of the total vehicle-kilometers travelled, in contrast to commuting trips. Consequently, they pay a relevant role in the economic, social and environmental impacts of transportation. This paper describes the development of a microscopic long-distance travel demand model for the Province of Ontario (Canada) and analyzes the sensitivity to the implementation of a new high speed rail corridor. Trip generation, destination choice and mode choice models were developed for this research. Multinomial logit models were estimated and calibrated using the Travel Survey for Residents in Canada (TSRC). It was complemented with location-based social network data from Foursquare, improving the description of activities and diverse land uses at the destinations. Level of service of the transit network was defined by downloading trip time, frequency and fare using the planning service Rome2rio. New scenarios were generated to simulate the impacts of a new high speed rail corridor by varying rail travel times, frequencies and fares of the rail services. As a result, a significant increase of rail modal shares was measured, directly proportional to speed and frequency and inversely proportional to price.
87

Delineation of Traffic Analysis Zone for Public Transportation OD Matrix Estimation Based on Socio-spatial Practices

Moghaddam, S. M. Hassan Mahdavi, Ameli, Mostafa, Rao, K. Ramachandra, Tiwari, Geetam 23 June 2023 (has links)
This paper aims to develop and validate an efficient method for delineation of public transit analysis zones (PTTAZ), particularly for origin-destination (OD) matrix prediction for transit operation planning. Existing methods have a problem in reflecting the level of spatial precision, travel characteristics, travel demand growth, access to transit stations, and most importantly, the direction of transit routes. This study proposes a new methodology to redelineate existing traffic analysis zones (TAZ) to create PTTAZ in order to allocate travel demand to transit stops. We aim to achieve an accurate prediction of the OD matrix for public transportation (PT). The matrix should reflect the passenger accessibility in the socioeconomic and socio-spatial characterization of PTTAZ and minimize intrazonal trips. The proposed methodology transforms TAZ-based to PTTAZ-based data with sequential steps through multiple statistical methods. In short, the generation of PTTAZ establishes homogeneous sub-zones representing the relationship between passenger flow, network structure, land use, population, socio-economic characteristics, and, most importantly, existing bus transit infrastructure. To validate the proposed scheme, we implement the framework for India’s Vishakhapatnam bus network and compare the results with the household survey. The results show that the PTTAZ-based OD matrix represents a realistic scenario for PT demand.
88

Transport Choices and Vehicle Ownership with Autonomous Vehicles : A modelling effort on car ownership, transport mode choice and travel demand with Driverless Technology. / Transportval och bilinnehav med autonoma fordon : En modellering av bilinnehav, transportval och reseefterfrågan med självkörande teknik.

Richter, Vide January 2018 (has links)
Transport is one of the basic needs of a functioning society. Unfortunately, transport also pollutes our cities and release greenhouses gases. Driverless technology is a technology predicted to disrupt the future transport system, and perhaps change how we travel from private cars to shared vehicles. This study focuses on the aspect of privately owned versus shared driverless vehicles, to create more knowledge of how the future transport system will look. A utility-based demand model is used to find the demand for private and shared transport when driverless vehicles are available. The utility of different transport options is estimated by looking at earlier studies about the performance of driverless cars, driverless buses and shared driverless taxis, which is used as input for the utility model. The results indicate that driverless technology will not be a catalyst that makes transport go from private to shared. While driverless buses can improve public transport, and shared driverless taxis outcompete current taxis, driverless technology will also improve private vehicles. The results in this study imply that the sustainability improvements earlier reports have predicted with a high use of shared driverless transportation might not materialise unless efforts are done to increase use of shared transportation. / Transport är ett av de grundläggande behoven för ett välfungerande samhälle. På samma gång släpper transporter ut både växthusgaser och skadliga partiklar. Självkörande teknik är något som förväntas revolutionera framtidens transportsystem, förhoppningen är att de ska förändra hur folk reser från privata bilar till delade transporter. Denna studie fokuserar på den förhoppningen. Kommer framtidens transporter ske i privata självkörande fordon eller delade självkörande fordon och vad i sin tur betyder det för framtidens transportsystem? Med en nyttobaserad efterfråge- och bilinnehavsmodell modelleras efterfrågan av självkörande delade taxis, självkörande bussar och självkörande privatbilar. Resultaten indikerar att självkörande teknik inte nödvändigtvis kommer vara en katalysator som får människor att sluta äga och använda privatbilar. Självkörande bussar kan göra kollektivtrafiken bättre, och självkörande delade taxibilar kommer troligtvis användas mer än dagens taxis. Men självkörande privatbilar kommer också ha många fördelar, och de som äger dem kommer dessutom troligtvis köra längre sträckor än dagens bilister. Resultatet av denna rapport indikerar därför att de stora förväntningarna som finns på självkörande teknik gällande delade transporter kan vara felaktiga, om inte andra åtgärder också görs för att öka delning. Att delningen inte ökar gör också att de hållbarhetsförbättringar som vissa tidigare rapporter förutspått inte nödvändigtvis kommer ske.
89

Telecommuting Travel Behavior: Examining the Influence of Work Status on Distance and Mode Choice in the National Capital Region

Garden, Benjamin W.C. 10 1900 (has links)
<p>This study explores telecommuter travel behaviour by examining discretionary travel distance and mode choice. The study utilizes data obtained from the 2005 origin-destination survey conducted by TRANS, a joint transportation planning committee serving the National Capital Region of Canada. The study compares and explains the discretionary travel behavior of teleworkers relative to other population groups and identifies that the average teleworker travels 3 times farther than regular workers and 1.7 times farther than non-workers for discretionary purposes. Regression indicates that dependent children, vehicle accessibility, housing type, residential distance to the urban core, land-use mix, residence within a Greenbelt region and day of the week all positively affect travel distance. Conversely, age, proximity to shopping centers and inclement weather demonstrate significant negative effects. Then, through binary logistic regression, the study confirms that work status significantly influences mode choice. Similarly, the following predictor variables demonstrate a significant positive effect towards active mode choice: teleworker work status, larger household size, greater income, warmer temperature, closer proximity to shopping centers, apartment housing type, trips for recreational and restaurant purposes, taking subsequent trips in a day, and travel between 8:00 A.M. and 4:00 P.M. On the contrary, increased entropy, trips within the Greenbelt region, dependent children under 16 years old, increased vehicle accessibility and trips for transporting someone or for shopping purposes all reduce the probability of active travel mode choice.</p> / Master of Arts (MA)
90

An analysis of urban transport demand in Windhoek : a case study of the Katatura and Khomsdal residential areas

Oherein, Daniel Lee Asikhia 11 1900 (has links)
Existing travel patterns in Windhoek are influenced by the past land use policy of restricted urban development in the former townships ofKatutura and Khomasdal. Thus residents in these townships are faced with longer distances to reach quality urban servtces. This thesis examined the impact on travel demand of changes in land use policies aimed at stimulating growth in the two areas using the HLFM computer model. The results showed that, policy induced land use changes may stimulate population and employment growth in the neglected areas, but with no effects on the present travel patterns. The model needs to be refined to fit the peculiarity of the study area. Nevertheless, information provided in the thesis could be used in assessing areas where development trends will go if any ofthe land use policy tested in the study is adopted. / Geography / M.A. (Geography)

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