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311.
This paper develops a comprehensive approach to the definition of transportation analysis zones (TAZ), and therein, presents
a new methodology and algorithm for the definition of TAZ embedded in geographic information systems software, improves the
base algorithm with several local algorithms, and comprehensively analyses the obtained results. The results obtained are
then compared to these presently used in the transportation analysis process of the Lisbon Metropolitan Area. The proposed
algorithm presents a new methodology for TAZ design based on a smoothed density surface of geocoded travel demand data. The
algorithm aims to minimise the loss of information when moving from a continuous representation of the origin and destination
of each trip to their discrete representations through zones, and focuses on the trade-off between the statistical precision,
geographical error, and the percentage of intra-zonal trips of the resulting OD matrix. The results for the Lisbon Metropolitan
Area case study suggest a significant improvement in OD matrix estimates compared to current transportation analysis practises
based on administrative units.
Luis M. Martínez is a Civil Engineer from the Instituto Superior Técnico, Technical University of Lisbon since 2004. After finishing his degree, he started his work as researcher in the CESUR (Civil Engineering & Architecture Department—Instituto Superior Técnico) where he has been working since. In 2006 he completed his Master Thesis at Instituto Superior Técnico on Traffic Analysis Zones modeling and started his PhD studies on the theme: Metropolitan Transportation Systems Financing Using the Value Capture Concept. José Manuel Viegas is Full Professor of Transportation at the Civil Engineering & Architecture Department of the Instituto Superior Técnico, Technical University of Lisbon. He has worked extensively in Modeling, Innovation and Policy in several types of Transport Systems. He was founder and first Director General of Transportnet, a group of eight leading European Universities with Advanced Studies in Transportation, and currently leads the Portuguese side of the Transportation Systems area in the MIT—Portugal program. Elisabete A. Silva is at the University of Cambridge (University Lecturer in Planning at the Department of Land Economy and a Fellow of Robinson College). With more than 100 contributions in peer review journals, books/books chapters, conference proceedings, and a research track record of approximately 16 years, (both at the public and private sector), her research interests are centred on the application of new technologies to spatial planning in particular city and metropolitan dynamic modelling through time. 相似文献
Elisabete A. SilvaEmail: |
Luis M. Martínez is a Civil Engineer from the Instituto Superior Técnico, Technical University of Lisbon since 2004. After finishing his degree, he started his work as researcher in the CESUR (Civil Engineering & Architecture Department—Instituto Superior Técnico) where he has been working since. In 2006 he completed his Master Thesis at Instituto Superior Técnico on Traffic Analysis Zones modeling and started his PhD studies on the theme: Metropolitan Transportation Systems Financing Using the Value Capture Concept. José Manuel Viegas is Full Professor of Transportation at the Civil Engineering & Architecture Department of the Instituto Superior Técnico, Technical University of Lisbon. He has worked extensively in Modeling, Innovation and Policy in several types of Transport Systems. He was founder and first Director General of Transportnet, a group of eight leading European Universities with Advanced Studies in Transportation, and currently leads the Portuguese side of the Transportation Systems area in the MIT—Portugal program. Elisabete A. Silva is at the University of Cambridge (University Lecturer in Planning at the Department of Land Economy and a Fellow of Robinson College). With more than 100 contributions in peer review journals, books/books chapters, conference proceedings, and a research track record of approximately 16 years, (both at the public and private sector), her research interests are centred on the application of new technologies to spatial planning in particular city and metropolitan dynamic modelling through time. 相似文献
312.
David Watling David MilneStephen Clark 《Transportation Research Part A: Policy and Practice》2012,46(1):167-189
In spite of their widespread use in policy design and evaluation, relatively little evidence has been reported on how well traffic equilibrium models predict real network impacts. Here we present what we believe to be the first paper that together analyses the explicit impacts on observed route choice of an actual network intervention and compares this with the before-and-after predictions of a network equilibrium model. The analysis is based on the findings of an empirical study of the travel time and route choice impacts of a road capacity reduction. Time-stamped, partial licence plates were recorded across a series of locations, over a period of days both with and without the capacity reduction, and the data were ‘matched’ between locations using special-purpose statistical methods. Hypothesis tests were used to identify statistically significant changes in travel times and route choice, between the periods of days with and without the capacity reduction. A traffic network equilibrium model was then independently applied to the same scenarios, and its predictions compared with the empirical findings. From a comparison of route choice patterns, a particularly influential spatial effect was revealed of the parameter specifying the relative values of distance and travel time assumed in the generalised cost equations. When this parameter was ‘fitted’ to the data without the capacity reduction, the network model broadly predicted the route choice impacts of the capacity reduction, but with other values it was seen to perform poorly. The paper concludes by discussing the wider practical and research implications of the study’s findings. 相似文献
313.
314.
ABSTRACTThe main goal of this study is the development of an aggregate air itinerary market share model. In order to achieve this, multinomial logit models are applied to distribute the city-pair passenger demand across the available itineraries. The models are developed at an aggregate level using open-source booking data for a large group of city-pairs within the US air transport system. Although there is a growing trend in the use of discrete choice models in the aviation industry, existing air itinerary share models are mostly focused on supporting carrier decision-making. Consequently, those studies define itineraries at a more disaggregate level using variables describing airlines and time preferences. In this study, we define itineraries at a more aggregate level, i.e. as a combination of flight segments between an origin and destination, without further insight into service preferences. Although results show some potential for this approach, there are challenges associated with prediction performance and computational intensity. 相似文献
315.
316.
IntroductionReasonably accurate mathematical modeling oftraffic engineering is needed not only for better un-derstanding of the collective behavior of traffic,but also for analyzing flow conditions, designingefficient control strategies, and etc[1]. For the pastfew decades, many researchers made studies of thissubject and a wide range of traffic flow theoriesand models have been developed. According to thelevel-of-detail with which the traffic flow is de-scribed, these traffic models were clas… 相似文献
317.
Neelu Seetaram 《Research in Transportation Economics》2010,26(1):27-36
Airfare elasticities are crucial for policy instruments for the stakeholders of tourism industry. Modellers attempting to estimate these elasticities face several challenges in the absence of microeconomic data on consumer preferences. The aim of this paper is to offer a critical analysis of the practice of computing airfare elasticities from tourism demand studies. It identifies and discusses potential sources of measurement errors in the data and drawbacks that investigators face and assesses their implications for the estimated parameters in the respective models. The use of price of crude oil and distance between origin and destination as proxies for transportation costs are evaluated. It is recommended that authors be more systematic in reporting their results. They need to comment on the limitations of their elasticity estimates since these have repercussions on policy recommendations made based on their results. 相似文献
318.
This paper explores the temporal stability of activity type-choice models and models of travelers' home-stay duration. To empirically evaluate this stability, a nested logit model of activity-type choice and a proportional hazards model of home-stay duration are estimated using data from two-day travel diaries collected in the fall of 1989 and again, from the same individuals, in the fall of 1990. The results show that the models are not temporally stable over the one year time period separating the two travel-diary samples. A number of possible reasons for this instability are discussed. 相似文献
319.
320.
For the planning and design of walking infrastructure, characterized by the fact that the pedestrians can choose their paths freely in two‐dimensional space, applicability of traditional discrete network models is limited. This contribution puts forward an approach for user‐optimal dynamic assignment in continuous time and space for analyzing for instance walking infrastructure in a two‐dimensional space. Contrary to network‐based approaches, the theory allows the traffic units to choose from an infinite non‐countable set of paths through the considered space. The approach first determines the continuous paths using a path choice model. Then, origin‐destination flows are assigned and traffic conditions are calculated. The approach to determine a user‐optimal assignment is heuristic and consists of a sequence of all‐or‐nothing assignments. An application example is presented, showing dynamic user equilibrium traffic flows through a realistic transfer station. The example is aimed at illustrating the dynamic aspects of the modeling approach, such as anticipation on expected flow conditions, and predicted behavior upon catching or missing a connection. 相似文献