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Social Equity Impacts of Congestion Management Strategies
This white paper examines the social equity impacts of various congestion management strategies. The paper includes a comprehensive list of 30 congestion management strategies and a discussion of equity implications related to each strategy. The authors analyze existing literature and incorporate findings from 12 expert interviews from academic, non-governmental organization (NGO), public, and private sector respondents to strengthen results and fill gaps in understanding. The literature review applies the Spatial â Temporal â Economic â Physiological â Social (STEPS) Equity Framework (Shaheen et al., 2017) to identify impacts and classify whether social equity barriers are reduced, exacerbated, or both by a particular congestion mitigation measure. The congestion management strategies discussed are grouped into six main categories, including: 1) pricing, 2) parking and curb policies, 3) operational strategies, 4) infrastructure changes, 5) transportation services and strategies, and 6) conventional taxation. The findings show that the social equity impacts of certain congestion management strategies are not well understood, at present, and further empirical research is needed. Congestion mitigation measures have the potential to affect travel costs, commute times, housing, and accessibility in ways that are distinctly positive or negative for different populations. For these reasons, social equity implications of congestion management strategies should be understood and mitigated for in planning and implementation of these strategies
TOOLS TO SUPPORT TRANSPORTATION EMISSIONS REDUCTION EFFORTS: A MULTIFACETED APPROACH
The transportation sector is a significant contributor to current global climatic problems, one of the most prominent problems that today's society faces. In this dissertation, three complementary problems are addressed to support emissions reduction efforts by providing tools to help reduce demand for fossil fuels. The first problem addresses alternative fuel vehicle (AFV) fleet operations considering limited infrastructure availability and vehicle characteristics that contribute to emission reduction efforts by: supporting alternative fuel use and reducing carbon-intensive freight activity. A Green Vehicle Routing Problem (G-VRP) is formulated and techniques are proposed for its solution. These techniques will aid organizations with AFV fleets in overcoming difficulties that exist as a result of limited refueling infrastructure and will allow companies considering conversion to a fleet of AFVs to understand the potential impact of their decision on daily operations and costs. The second problem is aimed at supporting SOV commute trip reduction efforts through alternative transportation options. This problem contributes to emission reduction efforts by supporting reduction of carbon-intensive travel activity. Following a descriptive analysis of commuter survey data obtained from the University of Maryland, College Park campus, ordered-response models were developed to investigate the market for vanpooling. The model results show that demand for vanpooling in the role of passenger and driver have differences and the factors affecting these demands are not necessarily the same. Factors considered include: status, willingness-to-pay, distance, residential location, commuting habits, demographics and service characteristics. The third problem focuses on providing essential input data, origin-destination (OD) demand, for analysis of various strategies, to address emission reduction by helping to improve system efficiency and reducing carbon-intensive travel activity. A two-stage subarea OD demand estimation procedure is proposed to construct and update important time-dependent OD demand input for subarea analysis in an effort to overcome the computational limits of Dynamic Traffic Assignment (DTA) methodologies. The proposed method in conjunction with path-based simulation-assignment systems can provide an evolving platform for integrating operational considerations in planning models for effective decision support for agencies that are considering strategies for transportation emissions reduction
Reshaped Urban Mobility
The application of novel solutions in vehicle and information technologies and the need for sustainability result in significant change in urban mobility. Moreover, autonomous vehicles (AVs) are expected to contribute to this alteration as well. The mobility is considered not only a single trip from A to B anymore but a comprehensive service. Shared and demand-driven services are more and more available besides traditional transportation modes. Modes are presented, evaluated, and compared, giving a realistic scenario for upcoming changes and opportunities. The development of the passenger transportation system requires an integrated approach considering user expectations. It is facilitated by the concept of Mobility-as-a-Service (MaaS), in which improvement of the quality has higher relevance than before. The impacts of the alteration are also summarized
Assessing the Efficiency of Mass Transit Systems in the United States
Frustrated with increased parking problems, unstable gasoline prices, and stifling traffic congestion, a growing number of metropolitan city dwellers consider utilizing the mass transit system. Reflecting this sentiment, a ridership of the mass transit system across the United States has been on the rise for the past several years. A growing demand for the mass transit system, however, necessitates the expansion of service offerings, the improvement of basic infrastructure/routes, and the additional employment of mass transit workers, including drivers and maintenance crews. Such a need requires the optimal allocation of financial and human resources to the mass transit system in times of shrinking budgets and government downsizing. Thus, the public transit authority is faced with the dilemma of âdoing more with less.â That is to say, the public transit authority needs to develop a âleanâ strategy which can maximize transit services with the minimum expenses. To help the public transit authority develop such a lean strategy, this report identifies the best-in-class practices in the U.S. transit service sector and proposes transit policy guidelines that can best exploit lean principles built upon best-in-class practices
Towards Understanding the Benefits and Challenges of Demand Responsive Public Transit- A Case Study in the City of Charlotte, NC
Access to adequate public transportation plays a critical role in inequity
and socio-economic mobility, particularly in low-income communities. Low-income
workers who rely heavily on public transportation face a spatial disparity
between home and work, which leads to higher unemployment, longer job searches,
and longer commute times. The overarching goal of this study is to get initial
data that would result in creating a connected, coordinated, demand-responsive,
and efficient public bus system that minimizes transit gaps for low-income,
transit-dependent communities. To create equitable metropolitan public
transportation, this paper evaluates existing CATS mobile applications that
assist passengers in finding bus routes and arrival times. Our community survey
methodology includes filling out questionnaires on Charlotte's current bus
system on specific bus lines and determining user acceptance for a future novel
smart technology. We have also collected data on the demand and transit gap for
a real-world pilot study, Sprinter bus line, Bus line 7, Bus line 9, and Bus
lines 97-99. These lines connect all of Charlotte City's main areas and are the
most important bus lines in the system. On the studied routes, the primary
survey results indicate that the current bus system has many flaws, the major
one being the lack of proper timing to meet the needs of passengers. The most
common problems are long commutes and long waiting times at stations. Moreover,
the existing application provides inaccurate information, and on average, 80
percent of travelers and respondents are inclined to use new technology.Comment: 22 pages, 54 figure
Bus timetable optimization model in response to the diverse and uncertain requirements of passengers for travel comfort
Most existing public transit systems have a fixed dispatching and service mode, which cannot effectively allocate resources from the perspective of the interests of all participants, resulting in resource waste and dissatisfaction. Low passenger satisfaction leads to a considerable loss of bus passengers and further reduces the income of bus operators. This study develops an optimization model for bus schedules that considers vehicle types and offers two service levels based on heterogeneous passenger demands. In this process, passenger satisfaction, bus company income, and government subsidies are considered. A bilevel model is proposed with a lower-level passenger ride simulation model and an upper-level multiobjective optimization model to maximize the interests of bus companies, passengers, and the government. To verify the effectiveness of the proposed methodology, a real-world case from Guangzhou is presented and analyzed using the nondominated sorting genetic algorithm-II (NSGA-II), and the related Pareto front is obtained. The results show that the proposed bus operation system can effectively increase the benefits for bus companies, passengers, and the governmen
Overview of Infrastructure Charging, part 4, IMPROVERAIL Project Deliverable 9, âImproved Data Background to Support Current and Future Infrastructure Charging Systemsâ
Improverail aims are to further support the establishment of railway infrastructure management in accordance with Directive 91/440, as well as the new railway infrastructure directives, by developing the necessary tools for modelling the management of railway infrastructure; by evaluating improved methods for capacity and resources management, which allow the improvement of the Life Cycle Costs (LCC) calculating methods, including elements related to vehicle - infrastructure interaction and external costs; and by improving data background in support of charging for use of railway infrastructure. To achieve these objectives, Improverail is organised along 8 workpackages, with specific objectives, responding to the requirements of the task 2.2.1/10 of the 2nd call made in the 5th RTD Framework Programme in December 1999.This part is the task 7.1 (Review of infrastructure charging systems) to the workpackage 7 (Analysis of the relation between infrastructure cost variation and diversity of infrastructure charging systems).Before explaining the economic characteristics of railway and his basic pricing principles, authors must specify the objectives of railways infrastructure charging.principle of pricing ; rail infrastructure charging ; public service obligation ; rail charging practice ; Europe ; Improverail
Concept of Advanced Personal Rapid Transit at Airports
The increase in air transportation demand implies challenges on airport ground access. Using private transportation mode to reach the airport is a typical practice which results in the vast demand for parking facilities. These facilities are located farther from the terminal, increasing the access time. This research aimed to develop the concept of an advance airport Personal Rapid Transit (PRT) that connects parking facilities to the terminal as a shuttle service, and provides on-board integrated flight-related services, such as check-in and baggage handling. The system architecture and operational models were developed, thus all relevant components and functions were identified, especially focusing on information management tasks. A questionnaire survey was performed and conducted at Budapest Airport to reveal the user expectations towards an advanced PRT service at the airport. Moreover, a layout selection method was developed which was applied to Budapest Airport as a case study. The proposed PRT service provides a seamless transit by access to airport terminals from remote parking facilities conveniently and the time consumption of flight-related activities is significantly reduced too
Welfare consequences of request stops at transport services with low demand
Background: Demand-responsive transport is an alternative to fixed-route, fixed-scheduled transport services in low-demand areas.
Objective: This paper discusses the welfare and distributional consequences of the implementation of request stops (RSs) on a scheduled fixed-stop transport service.
Method: The discussion is based on a general welfare model. The focus is on discussing how the magnitudes of the welfare effects on different groups of travellers are influenced by travel patterns and the characteristics of the travellers involved.
Results: The effects of implementing RSs are critically dependent on the booking procedure, the variation in demand throughout the day, and the travellersâ time values per hour when on the mode and when arriving at the destinations before having any appointments. Moreover, the benefits for the operators and the authorities depend strongly on the risk profile in the tendering contract.publishedVersio
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