22,649 research outputs found
Analysis of the Parameters of Transfers in Rapid Transit Network Design
The rapid transit network design problem consists of the location of train alignments and stations in an urban traffic context. The originality of our study is to incorporate into the location model the decisions about the transportation mode and the route, to be chosen for urban trips. This paper proposes a new design model which includes transfers between train lines. The objective of the model is to maximize the number of expected users in the transit network taking limited budgets into consideration, in addition to location and allocation constraints. Furthermore, the transfer costs are considered in the generalized public costs when the users change lines. Waiting time to take the metro and walking time to transfer is included in the formulation of the costs. The analysis of transfer parameters is carried out using a test network. Some computational experience is included in the paper
Analysis of the Parameters of Transfers in Rapid Transit Network Design
The rapid transit network design problem consists of the location
of train alignments and stations in an urban traffic context. The
originality of our study is to incorporate into the location model the
decisions about the transportation mode and the route, to be chosen
for urban trips. This paper proposes a new design model which includes
transfers between train lines. The objective of the model is to maximize
the number of expected users in the transit network taking limited budgets
into consideration, in addition to location and allocation constraints.
Furthermore, the transfer costs are considered in the generalized public
costs when the users change lines. Waiting time to take the metro and
walking time to transfer is included in the formulation of the costs. The
analysis of transfer parameters is carried out using a test network. Some
computational experience is included in the paper.Ministerio de Fomento 2003/1360Ministerio de Ciencia y Tecnología BFM2003-04062/MAT
Understanding Transit Ridership Demand for a Multi-Destination, Multimodal Transit Network in an American Metropolitan Area, Research Report 11-06
This study examines the factors underlying transit demand in the multi-destination, integrated bus and rail transit network for Atlanta, Georgia. Atlanta provides an opportunity to explore the consequences of a multi-destination transit network for bus patrons (largely transit-dependent riders) and rail patrons (who disproportionately illustrate choice rider characteristics). Using data obtained from the 2000 Census, coupled with data obtained from local and regional organizations in the Atlanta metropolitan area, we estimate several statistical models that explain the pattern of transit commute trips across the Atlanta metropolitan area. The models show that bus riders and rail riders are different, with bus riders exhibiting more transit-dependent characteristics and rail riders more choice rider characteristics. However, both types of riders value many of the same attributes of transit service quality (including shorter access and egress times and more direct trips) and their use of transit is influenced by many of the same variables (including population and employment). At the same time, the factors that influence transit demand vary depending on the type of travel destination the rider wishes to reach, including whether it is the central business district (CBD) or a more auto-oriented, suburban destination. The results of the study offer new insights into the nature of transit demand in a multi-destination transit system and provide lessons for agencies seeking to increase ridership among different ridership groups. The results suggest that more direct transit connections to dispersed employment centers, and easier transfers to access such destinations, will lead to higher levels of transit use for both transit-dependent and choice riders. The results also show that the CBD remains an important transit destination for rail riders but not for their bus rider counterparts. Certain types of transit-oriented development (TOD) also serve as significant producers and attractors of rail transit trips
A dynamic ridesharing dispatch and idle vehicle repositioning strategy with integrated transit transfers
We propose a ridesharing strategy with integrated transit in which a private
on-demand mobility service operator may drop off a passenger directly
door-to-door, commit to dropping them at a transit station or picking up from a
transit station, or to both pickup and drop off at two different stations with
different vehicles. We study the effectiveness of online solution algorithms
for this proposed strategy. Queueing-theoretic vehicle dispatch and idle
vehicle relocation algorithms are customized for the problem. Several
experiments are conducted first with a synthetic instance to design and test
the effectiveness of this integrated solution method, the influence of
different model parameters, and measure the benefit of such cooperation.
Results suggest that rideshare vehicle travel time can drop by 40-60%
consistently while passenger journey times can be reduced by 50-60% when demand
is high. A case study of Long Island commuters to New York City (NYC) suggests
having the proposed operating strategy can substantially cut user journey times
and operating costs by up to 54% and 60% each for a range of 10-30 taxis
initiated per zone. This result shows that there are settings where such
service is highly warranted
Improved rapid transit network design model: considering transfer effects
The rail rapid transit network design problem aims at locating train alignments and stations, maximizing demand coverage while competing with the current existing networks.
We present a model formulation for computing tight bounds of the linear relaxation of the problem where transfers are also introduced. The number of transfers within a trip is a decisive attribute for attracting passengers: transferring is annoying and undesirable for passengers. We conduct computational experiments on different networks and show how we are able to solve more efficiently problems that have been already solved; sensitivity analysis on
several model parameters are also performed so as to demonstrate the robustness of the new formulation
Improved rapid transit network design model: considering transfer effects
The rail rapid transit network design problem aims at locating train alignments and stations, maximizing demand coverage while competing with the current existing networks.
We present a model formulation for computing tight bounds of the linear relaxation of the problem where transfers are also introduced. The number of transfers within a trip is a decisive attribute for attracting passengers: transferring is annoying and undesirable for passengers. We conduct computational experiments on different networks and show how we are able to solve more efficiently problems that have been already solved; sensitivity analysis on
several model parameters are also performed so as to demonstrate the robustness of the new formulation
Bus rapid transit
Effective public transit is central to development. For the vast majority of developing city residents, public transit is the only practical means to access employment, education, and public services, especially when such services are beyond the viable distance of walking or cycling. Unfortunately, the current state of public transit services in developing cities often does little to serve the actual mobility needs of the population. Bus services are too often unreliable, inconvenient and dangerous.
In response, transport planners and public officials have sometimes turned to extremely costly mass transit alternatives such as rail-based metros. Due to the high costs of rail infrastructure, cities can only construct such systems over a few kilometres in a few limited corridors. The result is a system that does not meet the broader transport needs of the population. Nevertheless, the municipality ends up with a long-term debt that can affect investment in more pressing areas such as health, education, water, and sanitation.
However, there is an alternative between poor public transit service and high municipal debt. Bus Rapid Transit (BRT) can provide high-quality, metro-like transit service at a fraction of the cost of other options. This document provides municipal officials, non-governmental organizations, consultants, and others with an introduction to the concept of BRT as well as a step-by-step process for successfully planning a BRT system
Automated Transit Networks (ATN): A Review of the State of the Industry and Prospects for the Future, MTI Report 12-31
The concept of Automated Transit Networks (ATN) - in which fully automated vehicles on exclusive, grade-separated guideways provide on-demand, primarily non-stop, origin-to-destination service over an area network – has been around since the 1950s. However, only a few systems are in current operation around the world. ATN does not appear “on the radar” of urban planners, transit professionals, or policy makers when it comes to designing solutions for current transit problems in urban areas. This study explains ATN technology, setting it in the larger context of Automated Guideway Transit (AGT); looks at the current status of ATN suppliers, the status of the ATN industry, and the prospects of a U.S.-based ATN industry; summarizes and organizes proceedings from the seven Podcar City conferences that have been held since 2006; documents the U.S./Sweden Memorandum of Understanding on Sustainable Transport; discusses how ATN could expand the coverage of existing transit systems; explains the opportunities and challenges in planning and funding ATN systems and approaches for procuring ATN systems; and concludes with a summary of the existing challenges and opportunities for ATN technology. The study is intended to be an informative tool for planners, urban designers, and those involved in public policy, especially for urban transit, to provide a reference for history and background on ATN, and to use for policy development and research
Redesigning Large-Scale Multimodal Transit Networks with Shared Autonomous Mobility Services
Public transit systems have faced challenges and opportunities from emerging
Shared Autonomous Mobility Services (SAMS). This study addresses a city-scale
multimodal transit network design problem, with shared autonomous vehicles as
both transit feeders and a direct interzonal mode. The framework captures
spatial demand and modal characteristics, considers intermodal transfers and
express services, determines transit infrastructure investment and path flows,
and designs transit routes. A system-optimal multimodal transit network is
designed with minimum total door-to-door generalized costs of users and
operators, while satisfying existing transit origin-destination demand within a
pre-set infrastructure budget. Firstly, the geography, demand, and modes in
each clustered zone are characterized with continuous approximation. Afterward,
the decisions of network link investment and multimodal path flows in zonal
connection optimization are formulated as a minimum-cost multi-commodity
network flow (MCNF) problem and solved efficiently with a mixed-integer linear
programming (MILP) solver. Subsequently, the route generation problem is solved
by expanding the MCNF formulation to minimize intramodal transfers. To
demonstrate the framework efficiency, this study uses transit demand from the
Chicago metropolitan area to redesign a multimodal transit network. The
computational results present savings in travelers' journey time and operators'
costs, demonstrating the potential benefits of collaboration between multimodal
transit systems and SAMS.Comment: 44 pages, 15 figures, under review for the 25th International
Symposium on Transportation and Traffic Theory (ISTTT25
International Lessons for Promoting Transit Connections to High-Speed Rail Systems
As the California High-Speed Rail (HSR) project becomes reality, many communities involved in, or affected by, the California HSR project have considered how to connect the new HSR passenger services to local urban transportation systems – such as bus and light rail systems – and how they can take advantage of HSR accessibility and speed throughout the state. European and other overseas systems have decades of experience in forging connections between HSR and various transportation options. This study examines international HSR stations and identifies patterns in transit connections associated with stations on the basis of size, population levels, and other characteristics. Additionally, a closer examination is made of the lessons that can be learned from a strategic sample of overseas HSR stations, correlated to similar cities in the planned California system. Generally, the findings from the comparison suggest that California cities must make significant strides to approach the level of integration and ease of access to other modes that systems outside the U.S. now enjoy
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