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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

Enhancing the practical usability of dynamic traffic assignment

Pool, Christopher Matthew 04 March 2013 (has links)
A general framework is presented for replacing static traffic assignment with dynamic traffic assignment within the standard four step transportation planning model. Issues including model consistency and the implementation of a proper feedback loop are explored. The new model is compared with the standard four step model in order to highlight the benefits of using dynamic traffic assignment rather than static. The model is then extended to include a term for the difference between experienced and free-flow travel times, which can be used as a proxy for travel time reliability and highlights the benefits of time-dependent DTA. Additionally, a study on improving the quality of convergence for dynamic traffic assignment is conducted in order to help facilitate the usefulness of this modeling approach in practice. A variety of equilibration techniques are tested, and analysis is performed to contrast these techniques with the method of successive averages. / text
2

Development of a forecast model for public transport trips in smaller cities / Utveckling av en prognosmodell för kollektivtrafik i mindre städer

Hedström, Marie, Johansson, Johanna January 2015 (has links)
It has become more important for operators to be able to predict the future number of public transport passengers when consider to place a tender for operating public transport in a city or region, this is due to the new types of operator contracts was introduced quite recently. There are models in use today that can predict this, but they are often time consuming and complex and therefore it can be expensive to perform a forecast. Aside from this, most models in use for Sweden today are adapted for larger cities. Thus, the aim of this thesis is to propose a model that requires minimal input data with a short set up and execution time that can be used to predict a forecast for the public transport system in smaller cities without notably affecting the quality of the result. The developed model is based on a forecast model called LuTrans, which in turn is based on a common method, the four step model. The aim of the model lies within public transportation but it also consider other modes. The input data used by the model mainly consists of socio-economic data, the travel time and distance between all the zones in the network. The model also considers the cost for traveling by car or public transport. The developed model was applied to the Swedish city, Örebro, where a forecast was conducted for a future scenario. It is easily to apply the model to different cities to estimate a forecast for the public transport system. The developed model for the base scenario predicts trips for individual bus lines with an accuracy of 85 % for the city of Örebro. The developed model gave the result that the trips made by public transport in the future scenario of Örebro 2025 will increase annually by 0.94 %. The conclusion is that it is possible to develop a simple model that can be easily applied for a desired city. Although the developed model produced a plausible result for Örebro, further work such as implementation on other cities are required in order to fully evaluate the developed model.
3

Integration of the Transportation Systems Analysis Model for the Small Aircraft Transportation System

Hinze, Nicolas Karlsson 18 August 2005 (has links)
Standalone computer modules for county to county travel demand forecasting have been integrated. The Trip Generation, Trip Distribution and Mode Choice modules have been unified under one Graphical User Interface (GUI). The outputs are automatically mapped using Geographic Information Systems (GIS) technology to allow immediate and spatial analysis. The integrated model allows for faster running times and quicker analysis of the results. The ability to calculate travel time savings for travelers was also included to the final model. The modeling framework developed is known as the Transportation Systems Analysis Model (TSAM). / Master of Science
4

Quelle prise en compte des dynamiques urbaines dans la prévision de la demande de transport ? / How well are urban dynamics taken into account in travel demand forecasting?

Cabrera Delgado, Jorge 01 July 2013 (has links)
Dans la pratique de la planification urbaine, la prévision de la demande de transport fait en général appel au modèle à quatre étapes (génération, distribution, répartition modale et affectation), malgré des avancées théoriques considérables dans le domaine. Cette persistance s’explique par une facilité relative de mise en oeuvre, liée notamment à la forme des données disponibles et susceptibles d’alimenter les modèles. Cependant, la nature statique de l’approche pose des interrogations quant à sa pertinence pour faire des prévisions de moyen-long terme. Cette thèse étudie, la validité de l’hypothèse de stabilité temporelle des trois premières étapes du modèle de prévision. Pour ce faire, en prenant l’agglomération lyonnaise comme terrain d’étude, nous avons codifié des réseaux routiers et de transports en commun à différentes dates (1985, 1995 et 2006). Cette donne, généralement indisponible, combinée aux enquêtes ménages déplacements correspondantes, nous permet de calibrer les trois premières étapes du modèle traditionnel et de tester leur capacité prédictive. Pour les modèles de génération, on note des prévisions acceptables à un horizon de 10 ans. À 20 ans, certaines évolutions dans les styles de vie se sont traduites par une baisse du nombre moyen de sorties pour le motif travail, que les modèles traditionnels ne permettent pas de prévoir complètement. Au niveau de la distribution, l’allongement des distances entre lieux de réalisation de certaines activités et le lieu de domicile peut être relativement bien reproduit par des modèles gravitaires avec des paramètres stables dans le temps. Au niveau de la répartition modale, les paramètres ne sont pas stables et les modèles estimés n’auraient pas permis de prévoir le regain de parts de marché des transports en commun observé ces dernières années. / In the practice of urban planning, travel demand forecasts are generally obtained by using the four-step model (generation, distribution, modal split and assignment), despite considerable theoretical advances in the field. This persistence can be explained by the relative ease of implementation of the four-step modelling sequence, which is related, in particular, to the kind of data available that could be used as an input in a model. However, the static nature of the approach raises questions as it pertains to its relevance in producing medium and long range forecasts. This thesis investigates the validity of the hypothesis of temporal stability of the parameters of the first three stages of the traditional forecasting sequence. To do this, taking the Lyon conurbation as our case study, we coded the road and transit networks at different points in time (1985, 1995 and 2006). We then combine this temporal data, which is generally unavailable, with the corresponding household travel surveys in order to calibrate the first three steps of the traditional model and test their predictive ability. For the generation models tested, we note acceptable performance for a 10-year forecast. For a 20-year forecast, some changes in lifestyles have resulted in a decrease in the average number of work trips that traditional models do not predict accurately. Regarding trip distribution, the increase in travel distances observed for certain purposes is reproduced fairly well by the gravity model. At the modal split level, the parameters are not stable and the estimated models would be unable to predict accurately the recent increase in the market share of public transport.
5

Using public transport tap-in data to improve a travel demand model: A Norrköping case study

Drageryd, Lars January 2018 (has links)
With reliable models to forecast travel demand, traffic planners and decision-makers can be assisted in choosing the best solutions to obtain traffic performance goals. Practitioners have traditionally been relying on infrequent, costly and respondent pressurized travel surveys as their main source of data for these models. The drawbacks of the data collection method highlight a need to search for alternative sources of data used for the purpose. One such source is public transport “tap-in” data. This thesis executed a case study with the target of improving the travel demand model of Norrköping via public transport data. An algorithm that estimates the alighting station of travellers was applied to a data set provided by the public transport operator of the city. By allocating the OD-demand from stations to the traffic analysis zones used in the model a straightforward integration method using the tap-in estimate as a reference matrix could be used. The target with the method was to redistribute the demand in such a way that the public transport demand approached the tap-in estimate but that the total demand for all modes for the OD-pair remained unchanged. The results gave some indication that the integration of tap-in data improved the model performance from the perspective of public transports. In a regression analysis comparing the number of entries per station the integration of tap-in data increased the correlation coefficient from 0,845 to 0,864. Further was the performance for other transport modes seemingly not worsened by the integration of tap-in data. Finding an allocation procedure that was generic but still accurate proved complex. Further were drawbacks with the integration procedure highlighted where the method executed affected the results of the model, not its behaviour. The consequence of this is that, though the model might be an accurate representation of the current state of traffic, it is difficult to execute the same procedure when investigating future states. Still, the thesis stressed some of the potential for public transport data in modelling contexts, where the role of the data, given the procedure executed, still is of complementary character to travel surveys.
6

Modelling Effects of Car Sharing on Travel Behaviour

Söder, Isabelle January 2019 (has links)
Shared modes of transport, including car sharing, have been pointed out as one way of reducing private car use, contributing to an efficient transportation system that fulfills societal and environmental goals.Previous studies show that a share of car sharing users sells or refrains from acquire a new vehicle, when entering car sharing. Also, on average, car sharing has been shown to reduce Vehicle Kilometers Traveled (VKT) by car among the users.This study is conducted in three parts. First, a literature review of the effects of car sharing on travel behavior and car ownership is presented. Second, an implementation of car sharing in an existing transport model is described and the estimated effects are analyzed in relation to the findings in the literature study. In the final part, the car sharing module is reformulated to model a station-based car sharing system, where the distances to car sharing vehicles are used to distribute the effect of car sharing on car ownership spatially.This work contributes to the field by connecting the results from previous research about car sharing with practical transport modelling. The model of the station-based car sharing system is a useful tool for planners when considering the placement of car sharing stations. Also, this study provides an updated literature review covering findings of the effects of car sharing on travel behaviour and car ownership.Keywords: car sharing, station-based car sharing, travel demand modelling, vehicle ownership modelling, four-step model
7

[pt] AVALIAÇÃO DE CENÁRIOS DE INVESTIMENTOS NO SISTEMA DE TRANSPORTE DO RIO DE JANEIRO COM O SOFTWARE EMME / [en] EVALUATION OF INVESTMENT SCENARIOS IN THE TRANSPORT SYSTEM OF RIO DE JANEIRO WITH EMME SOFTWARE

JESSICA RODRIGUES DE OLIVEIRA 29 September 2020 (has links)
[pt] A mobilidade em médias e grandes cidades brasileiras como o Rio de Janeiro tem se caracterizado pela utilização ineficiente do espaço público, juntamente com a redução da utilização do transporte coletivo. Qualquer mudança nas rotas e frequências de linhas no transporte coletivo assim como o surgimento de novas tecnologias e variação das tarifas geram efeitos sobre a distribuição de fluxos de passageiros. Juntando-se a esse contexto, há a atual conjuntura econômica do Rio de Janeiro onde acaba não sobrando recursos para investir em estudos e na implementação de melhoria da mobilidade urbana da cidade. Este trabalho apresenta uma análise de alternativas de cenários focados no metrô e em conexões do BRT com trens por já terem uma infraestrutura pré-existente o que facilitaria a construção dessas obras. Esta pesquisa mostra como as obras incluídas nos cenários propostos para 2016 e 2021 no Plano Diretor de Transportes do Rio de Janeiro estão discrepantes com a rede de transporte no ano de 2019 e por consequência o fluxo de passageiros na rede é diferente do previsto. Com o auxílio do software EMME e utilizando uma rede de transporte simplificada e mais atualizada da Região Metropolitana do Rio de Janeiro, foi realizada a alocação do transporte coletivo baseado no modelo de estratégias ótimas de Spiess (1983), contido no EMME. Dessa forma verificou-se como a construção dessas novas infraestruturas de transporte alteraria o fluxo de passageiros. A partir desses resultados pode-se concluir que investir em conexões entre os modos e em obras que sejam capazes de retirar uma quantidade significativa de veículos da rede é um caminho chave para a Região Metropolitana já que esses investimentos deixam a rede de transporte menos congestionada e melhoram a qualidade de vida da população, além de seguir a apelo pelo desenvolvimento mais sustentável dos sistemas de transportes. / [en] Mobility in medium and large Brazilian cities such as Rio de Janeiro has been characterized by the inefficient use of public space, together with the reduction in the use of public transport. Any change in routes and line frequencies in public transport, as well as the emergence of new technologies and variation of fares, have an effect on the distribution of passenger flows. Adding to this context, there is the current economic situation in Rio de Janeiro, where there are no resources left to invest in studies and in the implementation of improving the city s urban mobility. This work presents an analysis of alternative scenarios focused on the trains and on BRT connections, as they already have a pre-existing infrastructure, which would facilitate the construction of these works. This research shows how the works included in the scenarios proposed for 2016 and 2021 in the Rio de Janeiro Transport Master Plan are discrepant with the transport network in 2019 and, consequently, the flow of passengers on the network is different from the forecast. With the aid of the EMME software and using a simplified and more up-to-date transportation network in the Metropolitan Region of Rio de Janeiro, public transportation was allocated based on the optimal strategies model of Spiess (1983), contained in the EMME. Thus, it was verified how the construction of these new transport infrastructures would alter the flow of passengers. From these results, it can be concluded that investing in connections between modes and in works that are capable of removing a significant number of vehicles from the network is a key path for the metropolitan region as these investments make the transportation network less congested and improve the population s quality of life, in addition to following the call for more sustainable development of transport systems.
8

How to make the most of open data? A travel demand and supply model for regional bicycle paths / Hur får man ut det mesta av öppna data? En modell för utbud och efterfrågan för planering av regionala cykelvägar

Cazor, Laurent January 2021 (has links)
Detta examensarbete syftar till att svara på ett av Trafikverket fastställt problem: en gemensam regional cykelplanerings process skulle göra dem billigare och mer jämförbara. De erbjuder för närvarande planerarna en modell som utvecklades av Kågeson 2007. Denna modell har formen av en rapport som ger råd om när man ska bygga en cykelväg mellan städer eller platser i en region. Ändå används den bara i endast 6 av de 21 svenska länen. Trafikverket kräver ett nytt planeringsstödverktyg, mer interaktivt och komplett än Kågeson-modellen. Några nya önskade funktioner är separationen av efterfrågan per syfte, införandet av e-cyklar, olika resesyfte och en prioritering av investeringarna.  Examensarbetet är att designa och implementera det här verktyget, även kallat Planning Support System (PSS), som syftar till att jämföra utbud och efterfrågan på cykelväg till prioritering av infrastrukturförbättringar. En huvudbegränsning för modellen är att den måste vara billig datavis, men så komplett och exakt som möjligt. Det baseras på flera öppna dataleverantörer, till exempel OpenStreetMap, den svenska nationella vägdatabasen (NVDB) eller reseundersökningar från Sverige och Nederländerna. Resultatet är en modell, uppdelad efter turändamål och typ av cykel.  Del för efterfrågeuppskattning anpassar en klassisk fyrsteg transportmodell till cykelplanering och begränsad data. För olika resändamål genereras och distribueras resor tack vare en ursprungs begränsad gravitationsmodell. Valet av cykelläge är anpassat till det faktiska resebeteendet genom logistisk regression med en binär logit-modell. Resorna tilldelas sedan nätverket med tilldelnings metoden "allt-eller-ingenting" genom Dijkstras algoritm. För att utvärdera cykelförsörjningen använde vi ett mått som heter Level of Traffic Stress (LTS), som uppskattar den potentiella användningen av en nätverkslänk för olika delar av befolkningen som en funktion av vägnätvariablerna. Prioriteringsrankningen är då förhållandet mellan mått på efterfrågan och utbud.  Detta nya verktyg implementeras med opensource Geographic Information System (GIS) som heter QGIS och med Python 3 och testas i Södermanlands län / This Master Thesis main objective is to answer a problem set by the Swedish Transport Administration: a common regional bicycle planning process would them cheaper and more comparable. They currently offer the planners a model developed by Kågeson in 2007. This model takes the form of a report which advises on when to build a bicycle path between cities or places of a region. Still, it is only used in only 6 of the 21 Swedish counties. Trafikverket requires a new planning support tool, more interactive and complete than the Kågeson model. Some new desired features are the separation of demand per purpose, the inclusion of e-bikes, different trip purposes, and a prioritization of the investments.  The Degree Project work is to design and implement this tool, also called Planning Support System (PSS), which compares supply and demand for bicycle path to prioritizing infrastructure improvements. A main constraint for the model is that it needs to be cheap data-wise, but as complete and precise as possible. It bases on several open data providers, such as OpenStreetMap, the Swedish National Road Database (NVDB), or Travel Surveys from Sweden and the Netherlands. The result is a model, disaggregated by trip purpose and type of bicycle.  The demand estimation part adapts a classic four-step transportation model to bicycle planning and limited data. For different trip purposes, trips are generated and distributed thanks to an origin-constrained gravity model. Bicycle mode choice is fit to actual travel behaviour through logistic regression with a binary logit model. The trips are then assigned to the network using the "all-or-nothing" assignment method through the Dijkstra algorithm. To evaluate bicycle supply, we used a metric called Level of Traffic Stress (LTS), which estimates the potential use of a network link by different parts of the population as a function of the road network variables. The prioritization ranking is then the ratio between demand and supply metrics.  This new tool is implemented with the opensource Geographic Information System (GIS) called QGIS and with Python 3, and it is tested on Södermanland County.
9

Raumstrukturelle Einflüsse auf das Verkehrsverhalten - Nutzbarkeit der Ergebnisse großräumiger und lokaler Haushaltsbefragungen für makroskopische Verkehrsplanungsmodelle

Wittwer, Rico 23 January 2008 (has links) (PDF)
Für die Verkehrsnachfragemodellierung stehen dem Planer sehr differenzierte Modellansätze zur Verfügung. Ein wesentliches Unterscheidungskriterium stellt dabei der Modellierungsgegenstand dar. Der Fokus der vorliegenden Arbeit ist auf makroskopische Verkehrsplanungsmodelle gerichtet. Es wird der Frage nachgegangen, in welcher Form die Ergebnisse großräumiger und lokaler Haushaltsbefragungen effizient bzw. sich gegenseitig ergänzend in Modellierungsaufgaben Einsatz finden können. Im Mittelpunkt der empirischen Datenanalyse steht die Frage, ob ein Unterschied in der Ausprägung zentraler modellierungsrelevanter Kenngrößen differenziert nach Raumtypen statistisch belegbar und planungspraktisch bedeutsam ist. Vor diesem Hintergrund wird auch die Auswirkung der komplexen Stichprobenpläne von MiD 2002 und SrV 2003 auf die Varianz der Parameterschätzung berücksichtigt. Ein in dieser Arbeit entwickelter, mehrstufiger Bewertungsalgorithmus, der dem Signifikanz-Relevanz-Problem hinreichend Rechnung trägt, bildet die Grundlage der Hypothesenprüfung. Er verbindet das Standardvorgehen (Signifikanztest) mit normativ gesetzten Effektgrößen und dem schätzerbasierten Vorgehen (Konfidenzintervalle). Eine besonders hohe Transparenz und Entscheidungskonsistenz erlangt der Ansatz dadurch, dass die Hypothesenprüfung auf Basis zweier voneinander unabhängig erhobener Untersuchungsgruppen (MiD, SrV) erfolgt. Die intensive Arbeit mit den Datengrundlagen MiD und SrV liefert eine Vielzahl von Erkenntnissen zur weiteren Qualifizierung des Erhebungsinstrumentes „Mobilität in Städten – SrV“. In Vorbereitung der im Jahre 2008 anstehenden Neuauflage der Erhebungsreihe wird nach Ansicht des Autors mit der Arbeit ein wesentlicher Impuls zur Weiterentwicklung der Methodik gegeben.
10

Raumstrukturelle Einflüsse auf das Verkehrsverhalten - Nutzbarkeit der Ergebnisse großräumiger und lokaler Haushaltsbefragungen für makroskopische Verkehrsplanungsmodelle

Wittwer, Rico 18 January 2008 (has links)
Für die Verkehrsnachfragemodellierung stehen dem Planer sehr differenzierte Modellansätze zur Verfügung. Ein wesentliches Unterscheidungskriterium stellt dabei der Modellierungsgegenstand dar. Der Fokus der vorliegenden Arbeit ist auf makroskopische Verkehrsplanungsmodelle gerichtet. Es wird der Frage nachgegangen, in welcher Form die Ergebnisse großräumiger und lokaler Haushaltsbefragungen effizient bzw. sich gegenseitig ergänzend in Modellierungsaufgaben Einsatz finden können. Im Mittelpunkt der empirischen Datenanalyse steht die Frage, ob ein Unterschied in der Ausprägung zentraler modellierungsrelevanter Kenngrößen differenziert nach Raumtypen statistisch belegbar und planungspraktisch bedeutsam ist. Vor diesem Hintergrund wird auch die Auswirkung der komplexen Stichprobenpläne von MiD 2002 und SrV 2003 auf die Varianz der Parameterschätzung berücksichtigt. Ein in dieser Arbeit entwickelter, mehrstufiger Bewertungsalgorithmus, der dem Signifikanz-Relevanz-Problem hinreichend Rechnung trägt, bildet die Grundlage der Hypothesenprüfung. Er verbindet das Standardvorgehen (Signifikanztest) mit normativ gesetzten Effektgrößen und dem schätzerbasierten Vorgehen (Konfidenzintervalle). Eine besonders hohe Transparenz und Entscheidungskonsistenz erlangt der Ansatz dadurch, dass die Hypothesenprüfung auf Basis zweier voneinander unabhängig erhobener Untersuchungsgruppen (MiD, SrV) erfolgt. Die intensive Arbeit mit den Datengrundlagen MiD und SrV liefert eine Vielzahl von Erkenntnissen zur weiteren Qualifizierung des Erhebungsinstrumentes „Mobilität in Städten – SrV“. In Vorbereitung der im Jahre 2008 anstehenden Neuauflage der Erhebungsreihe wird nach Ansicht des Autors mit der Arbeit ein wesentlicher Impuls zur Weiterentwicklung der Methodik gegeben.

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