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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.
31

Making Sense of Integrated Planning : Challenges to Urban and Transport Planning Processes in Sweden

Tornberg, Patrik January 2011 (has links)
The shaping of spatial structures at the urban, regional and national levels involves numerous kinds of actors and planning activities. In recent years, calls for crosssectoral coordination and integrated planning approaches echo extensively across different fields of planning. However, experiences from planning situations around Sweden and elsewhere reveal great challenges to such ambitions. This thesis explores key conditions for an integrated approach to urban and transport planning, focusing on the relationships between public professional actors and agencies involved in the interface between urban and transport planning and strategy making, at the local and national level in Sweden. The theoretical framework is based on communicative planning theory and theories on sensemaking. The empirical material emanates from the project The Livable City, a collaboration project between three Swedish municipalities and national authorities responsible for transport and urban planning in Sweden. The aim of The Livable City was to develop knowledge about integrated planning of the built environment and transport systems and to develop integrated processes for coordination of different interests, demands and needs. Case studies were conducted, based on document studies, interviews and observations. The results from this study illustrate various aspects of how plans and strategies in a multiperspective environment need to make sense to actors with different perspectives on what planning is all about. A sensemaking perspective on planning suggests that plans and strategies to promote an integrated approach to planning will always be partial and selective despite ambitions for these to be comprehensive or holistic. Commitment, reification and participation have in the cases proven to be useful concepts to understand the sensemaking aspect of planning practice. Interactive processes may inform the shaping of perspectives and can therefore be an element in efforts to promote integrated approaches to urban and transport planning, although the extent to which this may be achieved is highly dependent on contextual conditions and will vary from case to case. / QC 20111125
32

Arterial road travel time estimation and prediction

Lin, Hong-En January 2008 (has links)
In this research, a new approach for arterial road travel time estimation and prediction has been proposed and developed for providing reliable dynamic travel time information for arterial road networks. The results of the research should benefit arterial road traffic management and some travel time related applications. / Thesis (PhD)--University of South Australia, 2008
33

Active transport journey planner methodology

Hu, W. January 2009 (has links)
This research aims to define and develop a methodology to assist an individual traveller to select healthier and more sustainable transport routes and modes among admissible transport options and highlight the trade-offs among multiple objectives in terms of health, economic, social and environmental benefits. It aims to assist an individual traveller with multi-objectives to make more informed decisions in route and mode planning. The objectives in the case study were identified as personal energy expenditure, travel time, travel cost, CO2 emissions and energy resource consumption concerning sustainability. / This research presents procedures for estimating a range of costs and benefits for journeys; procedures for determining the optimal route for an individual’s trip in an urban area based on cost and benefit estimates and preference weights for specific objectives; procedures for undertaking sensitivity analysis for the optimal route; and uses of the cost and benefit estimation and optimal route generation procedures to conduct a case study for a realistic journey in Melbourne. / An active transport journey planner model was developed in MS Excel to allow users to set constraints for most objectives and give their corresponding weightings, respectively. The recommended transport solution (the least total disutility one) and ranking of other options along with their detailed objective-related information are derived. A case study shows that the methodology developed could be applied in selecting more informed transport solutions based on the user’s multi-objective preferences. In addition, transport options incorporating more cycling and walking have the higher probability to deliver healthier and more sustainable solution to users if social, environmental concerns were considered beyond economic issues. Meanwhile, in sensitivity analysis, the tornado diagrams and spiderplots diagrams are used for demonstrating how sensitive each transport option’s disutility is to the weightings of objectives.
34

Arterial road travel time estimation and prediction

Lin, Hong-En January 2008 (has links)
In this research, a new approach for arterial road travel time estimation and prediction has been proposed and developed for providing reliable dynamic travel time information for arterial road networks. The results of the research should benefit arterial road traffic management and some travel time related applications. / Thesis (PhD)--University of South Australia, 2008
35

In Whose Interest? A Critical Approach to Southeast Asia’s Urban Transport Dynamics

townsend@alcor.concordia.ca, Craig Townsend January 2003 (has links)
During recent decades, urban transport systems in Southeast Asia’s industrialising high growth economies were transformed. The ownership and use of privatelyowned cars and motorcycles grew in all cities, simultaneous to the introduction of new forms of public transportation including rail rapid transit in the larger metropolises. While these cities all experienced dynamic change, the relative rate and direction of the changes to urban transport systems varied greatly as did levels of success. Singapore emerged as a highly efficient transit metropolis whilst Bangkok and other cities gained notoriety as some of the world’s great traffic disasters. Why these differences emerged, particularly given a regional and global context of increasing interaction and exchange of ideas and of capital flows, presents a compelling question largely unanswered by previous research. A review of the general state of knowledge about urban transport worldwide reveals fundamental disagreements over basic questions such as the social value of motorisation, the relative merits of specific modes and technologies, and prescriptions for change. However, there is a general consensus that interest groups or rent-seekers influence urban transport, which can not be understand in solely technical or value-free terms. A literature review focused on Southeast Asian cities finds that in contrast to theoretical perspectives on cities of the industrialised world, there is less acknowledgement of interests and values and more emphasis on instrumental knowledge which can be used to address immediate problems such as rapid growth in motorisation, traffic congestion, and pollution. Questions such as who wins and who loses from changes to urban transport systems are not systematically examined in the existing literature on Southeast Asian cities. In order to address this gap, a case study analysis of three key cities, Bangkok, Kuala Lumpur, and Singapore is undertaken. This analysis utilises policy and planning documents, monographs and academic works, newspapers and archival materials, discussions with key informants, and participant observation, to reveal the significant actors and processes which shape urban transport. The study finds that the presence or absence of actors and complexions of interests in the development of urban land, urban transport equipment, infrastructure construction and operation, and local environmental improvements are linked to specific urban transport outcomes. The findings provide a basis for future research, particularly in cities of the developing world characterised by economic growth, rapid motorisation of urban transport systems, and substantial inequalities of wealth and power.
36

A importância da variabilidade do tempo de viagem no acesso terrestre a aeroportos: estudo de caso do Aeroporto Internacional André Franco Montoro. / The importance of travel time variability in airport ground access: study case - André Franco Montoro International Airport.

Bianca Bianchi Alves 26 September 2005 (has links)
Esta dissertação discute as questões de acesso terrestre a aeroportos. Em particular, estima a influência do fator de variabilidade do tempo de viagem na escolha modal de acesso terrestre ao Aeroporto Internacional André Franco Montoro, em Guarulhos, Região Metropolitana da Cidade de São Paulo (RMSP). Para isso, foi aplicada uma pesquisa de preferência declarada com 108 viajantes aéreos, realizada nas salas de embarque do referido aeroporto. Foram entrevistados apenas residentes da RMSP e predominantemente viajantes aéreos internacionais. Foram coletados também dados revelados: dados do indivíduo, do acesso terrestre realizado e da sua viagem aérea. Para a coleta dos dados de preferência declarada foi elaborado um experimento fatorial ortogonal de escolha. Cada indivíduo era questionado a proceder à ordenação de conjuntos de 4 alternativas, uma para cada modo considerado: automóvel, táxi e o serviço de ônibus existente, e um novo serviço proposto, um trem expresso ligando o aeroporto ao centro da cidade de São Paulo. As alternativas foram descritas pelos atributos de custo, tempo de viagem médio e variabilidade do tempo de viagem, expressa através de uma margem de segurança. Todos os atributos foram apresentados em 3 níveis. Com os dados coletados foram estimados modelos do tipo Logit Multinomial para diversos segmentos da amostra, estratificados por motivo de viagem (lazer ou trabalho), gênero, modo utilizado no acesso (carro ou táxi) e freqüência de viagens aéreas (alta ou baixa). Foram estimados modelos estatisticamente significativos para o segmento dos homens que viajaram nas sextas-feiras e para o segmento dos homens que utilizaram táxi no acesso ao aeroporto. Para estes casos, os coeficientes de margem de segurança e custo foram significativos, permitindo a estimação do valor de se melhorar a confiabilidade do tempo de viagem. A metodologia empregada neste trabalho pode ser estendida para incluir os outros segmentos dos usuários do aeroporto e permite uma melhor estimação da demanda para o trem expresso proposto. / The dissertation discusses and analyzes issues relating to ground access to airports, focusing on the importance of travel time reliability on the choice of transport mode for access to the André Franco Montoro International Airport of São Paulo, in Guarulhos. A stated preference survey was conducted with 108 air travelers waiting for departure at the André Franco Montoro Airport. Passengers interviewed had to be residents of the Metropolitan Regions of São Paulo; most individuals in the sample were traveling to international destinations. Revealed preference data about the trip to the airport as well as data about the air travel and other passenger attributes were collected. The stated preference survey was based on an orthogonal factorial design choice experiment. Each individual was asked to perform a ranking exercise on sets of 4 alternatives, one for each of the modes considered: auto, taxi and the existing bus service, and a new proposed express train linking the airport to the central area of São Paulo. Attributes describing each mode were cost, average travel time and a measure of travel time reliability, expressed as a safety margin, all factors presented in three levels. Multinomial Logit Models were estimated for several segments of the sample, stratified by purpose (leisure or work), gender, access mode (auto or taxi) and frequency of air travel (high or low). In general, average travel time and travel time reliability (safety margin) could not be jointly included in the models. Models segmented by trip purpose, gender or trip frequency did not present significant coefficients for safety margin or cost attributes. Valid and interesting models were estimated for the segment of men traveling on Fridays and for men using taxi as the access mode to the airport. In these cases, safety margin and travel cost coefficients were significant, allowing the estimation of the value of improving reliability of travel time. The methodology applied can be extended to include other segments of airport users and improve demand estimation for the proposed airport express train.
37

Identificação e caracterização de grupos de indivíduos segundo padrões de seqüências de atividades multidimensionais. / Identification and characterization of groups of individuals according to patterns of multidimensional activity sequences.

Ricardo Curvello Dalmaso 30 April 2009 (has links)
O presente estudo procura identificar grupos homogêneos de indivíduos quanto aos padrões de seqüências de atividades diárias que estes realizam. As atividades são caracterizadas por múltiplos atributos, fazendo com que as seqüências sejam multidimensionais. Como atributos, ou características, são considerados a natureza da atividade realizada, ou motivo da viagem, e o período de realização da mesma, ambos separados em categorias. É estudado o efeito da inclusão da forma de acesso à atividade, ou modo de viagem, como uma terceira dimensão. Este atributo, entretanto, dados os resultados obtidos, não é utilizado nas análises finais. É também considerada a adoção de diferentes categorizações para a dimensão motivo. São usados dados da pesquisa Origem e Destino realizada em 1997, na Região Metropolitana de São Paulo. No trabalho são considerados os indivíduos com 12 anos ou mais, com pelo menos duas viagens diárias e com seqüência de viagens iniciada e terminada em sua residência, sem inconsistências internas. O número de indivíduos que atende a estes critérios é 49.616. A classificação, ou agrupamento, das seqüências de atividades em classes ou grupos é feita considerando uma medida de distância ou dissimilaridade calculada entre as seqüências, que é baseada no esforço necessário para igualá-las. Esta medida é chamada de OT-MDSAM (uni-dimensional Optimum Trajectories-based MultiDimensional Sequence Alignment Method). A partir da matriz de dissimilaridades é executado um processo estatístico de agrupamento hierárquico aglomerativo usando o Método de Ward. Os grupos de seqüências formados são analisados considerando características das próprias seqüências e atributos sóciodemográficas e econômicas dos indivíduos que os compõem, e usados em um modelo de segmentação do tipo árvore de decisão, usando o CHAID (Chi-square Automatic Interaction Detector). Resultados indicam que os grupos formados são bastante homogêneos quanto aos padrões de seqüências de atividades que representam e aos indivíduos associados a eles. / The main objective of the dissertation is to identify homogeneous groups of individuals, with regard to the daily activity/travel sequences performed in a weekday. Activities are characterized by multiple attributes, thus generating mutidimensional seguences. In this study, the nature of the activity (travel purpose) and the starting period of engagement in the activity (ending time of a trip) were the dimensions considered in the characterization of activities. Access mode to the activity was also considered as a third dimension, but the results had led to the decision not to include it in the final analysis. Alternative categorizations of the activity nature dimension were also studied, that resulted in further disaggregation than adopted in previous analyses of the same data. The study used data from the 1997 Origin-Destination household survey of the Sao Paulo Metropolitan Area. The analysis considered all individuals aged 12 or over that conducted two or more trips (starting and ending at home) on the survey day, resulting in a sample of 49,616 individuals. A sequence alignment method - OT-MDSUM (uni-dimensional Optimum Trajectories-based MultiDimensional Sequence Alignment Method) - was used to compare and calculate distances between pairs of different activity/travel sequences. These distances were then fed into a Ward hierarchical clustering algorithm to create classes of groups of activity/travel patterns. These groups were then analyzed according to the characteristics of the activity/travel sequences included and to the sociodemographic and economic characteristics of individuals who performed these patterns. The data were then utilized to develop a decision tree model using CHAID - Chi-Squared Automatic Interaction Detector, having the group of activity/travel sequences as the response variable and the characteristics of individuals and their families as independent variables. The results indicate that the groups formed through this procedure present a good degree of homogeneity regarding the activity patterns they represent and that they can be clearly associated to the characteristics of the individuals which perform these patterns.
38

Estimating urban mobility with mobile network geolocation data mining / Estimation de la mobilité urbaine par l'exploitation des données de géolocalisation de téléphonie mobile

Bachir, Danya 25 January 2019 (has links)
Dans les prochaines décennies, la circulation et les temps de trajets augmenteront drastiquement en raison du fort taux d'accroissement de la population urbaine. L'augmentation grandissante de la congestion sur les réseaux de transports menace le bon fonctionnement des villes à plusieurs niveaux, tels que le bien-être des citoyens, la santé, l'économie, le tourisme ou la pollution.Ainsi, il est urgent, pour les autorités locales et nationales, de promouvoir l'innovation pour la planification urbaine, à l'aide d'une politique de soutien à l'innovation et de prises de mesures radicales.Pour guider les processus de décisions, il est crucial d'estimer, analyser et comprendre la mobilité urbaine au quotidien.Traditionnellement, les informations sur les déplacements des populations était collectées via des rapports nationaux et locaux, tels que les recensements et les enquêtes. Toutefois, ces derniers ont un coût important, induisant une très faible fréquence de mise-à-jour, ainsi qu'une temporalité restreinte des données.En parallèle, les technologies de l'information et de la communication fournissent une quantité de données de mobilité sans précédent, au jour le jour, toutes catégories de population confondues. En particulier, les téléphones portables accompagnent désormais la majorité des citoyens lors de leurs déplacements et activités du quotidien. Dans cette thèse, nous estimons la mobilité urbaine par l'exploration des données du réseau mobile, qui sont collectées en temps réel, sans coût additionnel, par les opérateurs télécoms. Le traitement des données brutes est non-trivial en raison de leur nature sporadique et de la faible précision spatiale couplée à un bruit complexe.La thèse adresse deux problématiques via un schéma d'apprentissage faiblement supervisé (i.e., utilisant très peu de données labellisées) combinant plusieurs sources de données de mobilité. Dans un premier temps, nous estimons les densités de population et le nombre de visiteurs au cours du temps, à une échelle spatio-temporelle relativement fine.Dans un second temps, nous construisons les matrices Origine-Destination qui représentent les flux totaux de déplacements au cours du temps, pour différents modes de transports.Ces estimations sont validées par une comparaison avec des données de mobilité externes, avec lesquelles de fortes corrélations et de faibles erreurs sont obtenues.Les modèles proposés sont robustes au bruit et à la faible fréquence des données, bien que la performance des modèles soit fortement dépendante de l'échelle spatiale.Pour atteindre une performance optimale, la calibration des modèles doit également prendre en compte la zone d'étude et le mode de transport. Cette étape est nécessaire pour réduire les biais générés par une densité urbaine hétérogène et les différents comportements utilisateur.Ces travaux sont les premiers à estimer les flux totaux de voyageurs routiers et ferrés dans le temps, à l'échelle intra-régionale.Bien qu'une validation plus approfondie des modèles soit requise pour les renforcer, nos résultats mettent en évidence l'énorme potentiel de la science des données de réseaux mobiles appliquées à la planification urbaine / In the upcoming decades, traffic and travel times are expected to skyrocket, following tremendous population growth in urban territories. The increasing congestion on transport networks threatens cities efficiency at several levels such as citizens well-being, health, economy, tourism and pollution. Thus, local and national authorities are urged to promote urban planning innovation by adopting supportive policies leading to effective and radical measures. Prior to decision making processes, it is crucial to estimate, analyze and understand daily urban mobility. Traditionally, the information on population movements has been gathered through national and local reports such as census and surveys. Still, such materials are constrained by their important cost, inducing extremely low-update frequency and lack of temporal variability. On the meantime, information and communications technologies are providing an unprecedented quantity of up-to-date mobility data, across all categories of population. In particular, most individuals carry their mobile phone everywhere through their daily trips and activities. In this thesis, we estimate urban mobility by mining mobile network data, which are collected in real-time by mobile phone providers at no extra-cost. Processing the raw data is non-trivial as one must deal with temporal sparsity, coarse spatial precision and complex spatial noise. The thesis addresses two problematics through a weakly supervised learning scheme (i.e., using few labeled data) combining several mobility data sources. First, we estimate population densities and number of visitors over time, at fine spatio-temporal resolutions. Second, we derive Origin-Destination matrices representing total travel flows over time, per transport modes. All estimates are exhaustively validated against external mobility data, with high correlations and small errors. Overall, the proposed models are robust to noise and sparse data yet the performance highly depends on the choice of the spatial resolution. In addition, reaching optimal model performance requires extra-calibration specific to the case study region and to the transportation mode. This step is necessary to account for the bias induced by the joined effect of heterogeneous urban density and user behavior. Our work is the first successful attempt to characterize total road and rail passenger flows over time, at the intra-region level.Although additional in-depth validation is required to strengthen this statement, our findings highlight the huge potential of mobile network data mining for urban planning applications
39

Three essays on transport CBA uncertainty

Almström, Peter January 2015 (has links)
Cost Benefit Analysis (CBA) has for a long time been used in transport planning, but it is often questioned. One main argument against CBA is that the results depend largely on assumptions regarding one or a few input factors, as for example the future fuel price or valuation of CO2 emissions. The three papers included in this thesis investigate some aspects of uncertainty in transport CBA calculations. The two first papers explore how changes in input data assumptions affect the CBA ranking of six rail and road investments in Stockholm. The first paper deals with the effect of different land-use assumptions while the second deals with the influence of economic growth, driving cost and public transport fare. The third paper investigates how alternative formulations of the public transport mode choice and route choice affect travel flows, ticket revenues and consumer surplus. These are important factors previously known to affect CBA results. The findings of the first two papers suggest that CBA results are robust concerning different land-use scenarios and single input factors. No change in rank between a road and a rail object is observed in the performed model calculations, and only one change between two road objects. The fact that CBA results seem robust regarding input assumptions supports the use CBA as a tool for selecting transport investments. The results in the third paper indicate that if there is detailed interest in, for example, number of boardings and ticket income from a certain transit line, or the total benefit of a price change, a more detailed formulation of the public transport mode choice and route choice will provide more reliable results. On the other hand, this formulation requires substantially more data on the transit line and price structure than the conventional formulation used in Swedish transport planning, especially in areas with many different pricing systems. / <p>QC 20150414</p>
40

Perceived Accessibility : Capturing the Traveller Perspective

Lättman, Katrin January 2016 (has links)
The main purpose of this thesis is introducing and proposing perceived accessibility as an important and so far overseen complement to conventional, objective accessibility in sustainable transport. Perceived accessibility is defined as the possibilities and ease of engaging in preferred activities using different transport modes. Implications for sustainable transport planning along with possible social outcomes related to perceived accessibility are also discussed.   The thesis comprises two empirical studies. In Study I a psychometric measure (PAC) that captures perceived accessibility was developed and validated in three different datasets by exploratory and confirmatory factor analyses. All data was collected in Karlstad, Sweden in 2013 and 2014 with a total of 750 participants (bus travelers). Perceived accessibility is suggested as a complement to objective accessibility by contributing with the traveler perspective.  Study II aimed at examining determinants of perceived accessibility focusing on service quality aspects, feelings of safety, age, and trip frequency. Study II used the same data as Study I in a conditional process model to look at the relations between perceived accessibility and its proposed determinants. Service quality and feelings of safety were found important predictors of perceived accessibility, and safety also explains part of the effect of quality on perceived accessibility. These relationships were not dependent on trip frequency (as in how often one travels by public transport). Age also predicted perceived accessibility, and a follow-up cluster analysis showed that elderly and people in their thirties experience significantly lower perceived accessibility than other age groups. / Denna licentiatuppsats behandlar upplevd tillgänglighet, det vill säga resenärsperspektivet på tillgänglighet, som ett viktigt komplement till konventionell (objektiv) tillgänglighet inom hållbart resande. Uppsatsen introducerar upplevd tillgänglighet och dess nytta och plats i forskningen samt implikationer för planering och utvärdering av hållbara transporter. Vidare behandlas påverkansfaktorer för upplevd tillgänglighet samt relaterade individuella utfall som subjektivt välbefinnande och social exkludering/inkludering utifrån teori och empiri.   Uppsatsen innefattar två empiriska studier. Studie I utvecklar och testar ett psykometriskt mätinstrument för upplevd tillgänglighet med data från tre enkät-tillfällen (n= 750) i Karlstad. Dataset 1 analyserades med explorativ faktoranalys för att få fram ett instrument som fångar upplevd tillgänglighet (PAC) och validerades därefter i två dataset. Studie II avsåg att undersöka vad som bidrar till upplevd tillgänglighet med fokus på kvalitetsattribut i resan (service quality), resenärens upplevda trygghet, samt ålder och resvana. Samma data som i studie I användes i en conditional process model för att undersöka sambanden, samt i en klusteranalys för att ytterligare undersöka skillnader i resultatet mellan olika grupper av resenärer. Resultatet visar att upplevd tillgänglighet kan ha betydelse som komplement till befintliga mätningar och utvärderingar av tillgänglighet genom att bidra med resenärsperspektivet. Ett antal påverkansfaktorer för upplevd tillgänglighet kan konstateras, däribland kvalitet samt resenärens upplevda känsla av trygghet. Betydelsen av kvalitet för tillgänglighet är densamma oavsett hur ofta man reser, däremot upplever de som reser ofta en signifikant högre tillgänglighet än de som reser sällan. Äldre resenärer och resenärer i 30-årsåldern påvisar signifikant lägre upplevd tillgänglighet. / This thesis proposes perceived accessibility as a complement to conventional accessibility in sustainable transport planning and evaluation. Perceived accessibility is defined as the possibilities and ease of engaging in preferred activities using different transport modes and captures the traveller experience and perspective of accessibility. The thesis introduces an instrument for measuring perceived accessibility (PAC) along with determinants for perceived accessibility, such as feelings of safety, age, and perceived quality. Related social outcomes such as social inclusion and subjective well-being are discussed, along with possible implications for transport planning and suggestions for future research.

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