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1.
Cycling confers transport, health and environmental benefits, and bicycle sharing systems are an increasingly popular means of promoting urban cycling. Following the launch of the London bicycle sharing system (LBSS) in 2010, women and residents of deprived areas were under-represented among initial users. This paper examines how the profile of users has changed across the scheme’s first 3 years, using total-population registration and usage data. We find that women still make fewer than 20% of all ‘registered-use’ LBSS trips, although evidence from elsewhere suggests that the introduction of ‘casual’ use has encouraged a higher overall female share of trips. The proportion of trips by registered users from ‘highly-deprived areas’ (in the top tenth nationally for income deprivation) rose from 6% to 12%. This was due not only to the 2012 LBSS extension to some of London’s poorest areas, but also to a steadily increasing share of trips by residents of highly-deprived areas in the original LBSS zone. Indirect evidence suggests, however, that the twofold increase in LBSS prices in January 2013 has disproportionately discouraged casual-use trips among residents of poorer areas. We conclude that residents in deprived areas can and do use bicycle sharing systems if these are built in their local areas, and may do so progressively more over time, but only if the schemes remain affordable relative to other modes.  相似文献   

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In the vehicle routing problem, a fleet of vehicles must service the demands of customers in a least-cost way. By allowing multiple vehicles to service the same customer (i.e., splitting deliveries), substantial savings in travel costs are possible. However, split deliveries are often an inconvenience to the customer who would prefer to have demand serviced in a single visit. We consider the vehicle routing problem in which split deliveries are allowed only if a minimum fraction of a customer’s demand is serviced by a vehicle. We develop a heuristic method for solving this problem and report computational results on a wide range of problem sets.  相似文献   

4.
Emerging transportation technologies have the potential to significantly reshape the transportation systems and household vehicle ownership. Key among these transportation technologies are the autonomous vehicles, particularly when introduced in shared vehicle fleets. In this paper, we focus on the potential impact that fleets of shared autonomous vehicles might have on household vehicle ownership. To obtain initial insights into this issue, we asked a sample of university personnel and members of the American Automobile Association as to how likely they would consider relinquishing one of their household's personal vehicles if shared autonomous vehicles were available (thus reducing their household vehicle ownership level by one). For single-vehicle households, this would be relinquishing their only vehicle, and for multivehicle households (households owning two or more vehicles) this would be relinquishing just one of their vehicles. Possible responses to the question about relinquishing a household vehicle if shared autonomous vehicles are present are: extremely unlikely, unlikely, unsure, likely, and extremely likely. To determine the factors that influence this response, random parameters ordered probit models are estimated to account for the likelihood that considerable unobserved heterogeneity is likely to be present in the data. The findings show that a wide range of socioeconomic factors affects people's likelihood of vehicle relinquishment in the presence of shared autonomous vehicles. Key among these are gender effects, generational elements, commuting patterns, and respondents' vehicle crash history and experiences. While people's opinions of shared autonomous vehicles are evolving with the continual introduction of new autonomous vehicle technologies and shifting travel behavior, the results of this study provide important initial insights into the likely effects of shared autonomous vehicles on household vehicle ownership.  相似文献   

5.
Adoption of electric vehicles by transport companies remains limited although major European cities should reach CO2-free city logistics by 2030. This paper explores therefore the vehicle choice behaviour of transport companies through a conjoint-based choice analysis.The results showed that the benefits of battery electric vehicles are less valued than their disadvantages. However, a majority of respondents agrees that authorities should encourage the use of battery electric vehicles. Based on the preferences of transporters, we conclude that the most important measures are to develop a larger charging infrastructure and implement financial incentives through subsidies or tax exemption.  相似文献   

6.
Docked bike-share programs have proliferated worldwide, but studies find that the distribution of docked stations is geographically unequal. New dockless systems offer more flexibility compared to docked systems, but it remains unclear if dockless systems can address existing geographic inequities. This study examines all 32 US cities with both docked and dockless micromobility (bikeshare and e-scooter) programs and develops three service geography indicators to compare the geographic equity of docked versus dockless systems. We first use Lorenz curves and Gini indices to examine the overall spatial distribution of micromobility; we then use logistic and Tobit regressions to investigate how service geography corresponds to neighborhood characteristics. Results show that the distribution of docked systems is extremely unequal, and that dockless systems greatly reduce geographical inequalities relative to docked. Low-density areas and neighborhoods with low median household incomes, smaller shares of young people, and fewer zero-car households have limited micromobility service. Docked services are less prevalent in communities of color, and the implementation of dockless systems yields mixed outcomes for racial equity. Importantly, designated service areas do not always translate into available micromobility vehicles. Policymakers should use program design and performance metrics to address the mismatch between designated and actual service geographies and to ensure that micromobility services benefit marginalized communities.  相似文献   

7.
The paper examines the travel behaviour of residents in four key metropolitan areas in Ghana with data from 926 respondents including 451 females obtained at intra-commuter vehicle terminals. The analysis of the data showed that the Ghana Private Road Transport Union (GPRTU) continues to dominate in the intra-urban commuter service. Also, in spite of persistent complaints from consumers about the high cost of transport fares, it is rather the cost of food, children’s education, clothing and to some extent personal entertainment which consume a disproportionate share of residents’ disposable incomes. Notwithstanding this finding, respondents’ expectation is to pay less than they are doing now for commuting within the study areas.  相似文献   

8.
Floods are becoming more frequent and the magnitude of direct consequences, relating to destruction of critical infrastructure and loss of life, has highlighted the importance of flood management. This study proposes a methodology for quantifying the impact of predicted and historic flood events on emergency services. The approach moves beyond simple flood inundation mapping by accounting for the relationship between flood depth and vehicular speed. A case study is presented for Calgary, Alberta, where the depths of a predicted 100-year flood and a historic 2013 flood event are modeled. The methodology applies geographic information systems to flood depth mapping, utilizing digital elevation models, flood extents, and hydrological data. Flood depths are then assigned to links comprising the road network, where the maximum vehicle speed is calculated as a function of the standing depth of water on a link. The flooded network is used to derive service areas for several types of emergency services (emergency medical services (EMS), fire, and police), following targeted response times. The results locate and quantify the residential and work populations that no longer meet the targeted response times. During both flood scenarios, EMS is found to have the greatest reduction in accessibility, with 23% and 47% of residents and workers, respectively, not served. Fire services are seen to be more resilient with only 3% and 9% of residents and workers, respectively, not served. The results for police services are similar to fire services. However, the former have a greater range of response times, meaning these areas represent those that are completely isolated during both flood events. Overall, the integrated methodology quantifies vulnerable populations on a partially degraded network, the results of which can be used to develop evacuation plans and emergency response strategies.  相似文献   

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Since public transport deregulation in the UK the provision of solutions to transport demand in areas of dispersed demand has been met by local authorities’ attempts to “fill gaps” in the commercial public transport network, whilst the voluntary sector has addressed the needs of more specialised travel. Over the last five years more innovative solutions have been enabled by the development of Intelligent Transport Systems (ITS), which allow more flexible transport services in terms of time and space. In addition, new ways of thinking about the provision of what might be considered public transport has led to more flexible transport modes becoming available, permitting the general public on education contract services, the use of taxis for shared public transport and the provision of vehicles enabling access to work. However, these innovations tend to operate independently leading to overlap, gaps and misunderstandings about the purpose, delivery and receipt of services. To address these issues, future public transport services will need wider area network planning, greater co-operation between service providers (e.g. in the form of partnerships) and improved understanding of passenger requirements. The case study of Northumberland presented in this paper embodies many of the problems faced by residents in rural areas of the UK to-day and illustrates diverse solutions that have been made to address these challenges.  相似文献   

11.
Carsharing is considered one of the solutions to urban transport problems. As a new mode in the urban transport system in China, there are still initial questions of how carsharing will perform and what the impacts will be. Accordingly, this study considers battery electric vehicle sharing and investigates its potential demand, with Beijing as the case study. A nested logit model is established and calibrated to analyze mode choice behavior. Further, real trip data is used to estimate the potential demand for battery electric vehicle sharing. In addition, the temporal and spatial distribution of potential demand, the impact of battery electric vehicle sharing on the mode split, and the impact of pricing strategies are analyzed. The results show that an optimistic mode split of battery electric vehicle sharing is 4.23% when the average distance between travelers and stations is 0.5 km. The main source of potential demand is public transport. However, the substitution effect of battery electric vehicle sharing for private vehicles is weak. The potential trips are concentrated in the morning peak period, mainly starting in residential or integrative areas, and ending in commercial areas or green spaces. Commuting and long-distance trips are more sensitive to decreases in price, such that they are more likely to be completed as battery electric vehicle sharing trips. This price decrease could also increase the potential trip ratio during the evening peak period. These findings are useful to governments and operators for implementing policies such as station planning, relocation, and pricing strategies.  相似文献   

12.
The recent growth of new mobility services such as car-sharing (ZipCar, Car2Go) and ride-hailing (Uber, Lyft) has interesting implications for new vehicle technologies. We explore the users of the services and their relation to electric vehicles preferences by analyzing two large-scale mobility service surveys. A number of categories (car-share usage, ride-hail usage, commute mode, demographics, current vehicle attributes, environmental attitudes, technology attitudes, and life-stage information) are examined in order to determine the likelihood a respondent considers purchasing an electric vehicle in the future. Survey respondents explicitly expressed that exposure to ride-hailing did not increase their propensity for wanting to purchase an electric vehicle in the future. However, we run a full suite of cross-validation models and find that in addition to the typical factors used in modeling preferences, the use of new mobility services statistically increases the predictive power of our model to identify preferences for electric vehicles.  相似文献   

13.
Bus Rapid Transit (BRT) systems are an increasingly popular public transport option internationally. They provide rail-like quality for bus services for a fraction of the cost of fixed rail. Many claims of high and increasing ridership have resulted from BRT system development; however, it is unclear exactly which aspects of BRT system design drive this. This paper explores whether BRT design features, among other influences, significantly increase ridership above and beyond the impact of service levels. It does so using a series of regression models undertaken on 77 BRT and non-BRT bus routes in Australia which is known for its diversity in BRT route design. Explanatory variables used included service level, frequency, speed, stop spacing, share of segregated right of way, vehicle accessibility, employment and residential density, car ownership levels and BRT infrastructure quality. Five models explored the role of these variables. Two models found that service level dominates predictions of boardings per route km although they suffer from endogeneity. Further models control for this influence by modelling boardings per vehicle km. Overall results suggest that some BRT infrastructure treatments such as right of way have a significant impact on ridership but the influence of infrastructure is within the context of high service levels. The role of accessible vehicles has also been highlighted in this research, although more research is needed to clarify this influence. The paper concludes with a discussion of the various influences on ridership and recommendations for existing policy and future research.  相似文献   

14.
Although the need for more environmentally friendly vehicles was recognized some decades ago, this new market has not yet established itself. Consumer behavior needs to be studied to ascertain when people will decide to purchase hybrid or electric vehicles rather than conventional ones. An in-depth review of the state-of-the-art has identified existing deficiencies and these are addressed in this paper, proposing a new approach that is applied to the case of Santander in Spain. Emphasis is placed on the role of citizens in researching the local market and their requirements with respect to such vehicles; our model assumes variability in user preferences, an utmost requirement as concluded from the literature review. Results suggest that the highest demand for cleaner vehicles would be achieved in two ways: firstly, by penalizing conventional vehicles in terms of costs/km; secondly, by providing incentives directed at lowering the purchasing price of hybrid and electric vehicles. Finally, as demand becomes more elastic, the preferred strategy should initially focus on hybrid vehicles.  相似文献   

15.
This paper addresses the planning of recyclable waste collection systems while accounting for economic and environmental concerns. Service areas and vehicle routes are defined for logistics networks with multiple depots where different products are collected. The problem is modeled as a multi-product, multi-depot vehicle routing problem with two objective functions: distance and CO2 emissions minimization. A decomposition solution method is developed and applied to a real case study. Six scenarios regarding different service areas and objective functions are studied. Savings of up to 22% in distance and 27% in CO2 emissions are achieved, exceeding economic and environmental goals.  相似文献   

16.
The improvement of rural people's mobility in developing countries has informed many policies. Still, debates remain on which policies are efficient, for instance, building more roads, providing public transport or promoting car ownership. The empirical evidence for these debates at the national level remains scarce. As a result, this paper aims to provide fresh evidence for discussions by examining residents' mobility in China using nationwide survey data with 12,524 respondents from 119 rural towns. The results of the analysis show car ownership is the most significant factor influencing rural people's mobility than other factors. Higher car ownership relates to a higher travel frequency to counties or cities. Other kinds of transport vehicles (i.e. electric cars, motorcycles and electric bikes) also have positive but relatively weaker impacts on rural mobility. For public transport, it is more accessible to access bus stops, which encourages travel to higher-order centres rather than increasing the frequency of county bus services. The accessibility of high-quality road systems tends to have a negative influence and has combined effects with levels of local services. People from towns with insufficient local services and poor access to highways travel the most frequently to higher-order centres. This study highlights the critical role of road investments and car ownership enhancement policies in improving mobility. Moreover, this study also underscores the supplemental role of public transport services given the current low car ownership rates in rural towns of China and the global consensus on sustainable green transport development. It highlights the importance of engaging eco-friendly and locally adaptive transport alternatives, such as electric cars and electric bikes. It also calls for a rational distribution of bus stops and more flexible, convenient, and physically accessible public transport and carshare modes in rural China.  相似文献   

17.
The green vehicle routing and scheduling problem (GVRSP) aims to minimize green-house gas emissions in logistics systems through better planning of deliveries/pickups made by a fleet of vehicles. We define a new mixed integer liner programming (MIP) model which considers heterogeneous vehicles, time-varying traffic congestion, customer/vehicle time window constraints, the impact of vehicle loads on emissions, and vehicle capacity/range constraints in the GVRSP. The proposed model allows vehicles to stop on arcs, which is shown to reduce emissions up to additional 8% on simulated data. A hybrid algorithm of MIP and iterated neighborhood search is proposed to solve the problem.  相似文献   

18.
This paper develops a mathematical model for the optimal stopping design of limited-stop bus service, which allows each bus vehicle to skip some stops. To better reflect the reality, this paper considers the vehicle capacity and stochastic travel time. Also, vehicles are all allowed to skip stops whereas any stop is not allowed to be skipped by two consecutive vehicles. A hybrid artificial bee colony (ABC) and Monte Carlo method is developed to solve the optimal stopping strategy. Finally, the model and solution method are validated by a numerical example, and a sensitivity analysis is performed on the passenger demand.  相似文献   

19.
Bus Rapid Transit (BRT) is being implemented as a neoliberal project, but it creates contradictions that challenge the premise of neoliberalism. BRT projects are affordable rapid transit infrastructure, but they are also an impetus to restructure the urban bus sector in developing cities with informal mass transport. The dominant model of BRT implementation creates a market for bus service from large private companies where the government takes on the risk and brands the service as part of the city's attempt to be a ‘world class’ city that can attract mobile capital. However, BRT and the formalization of the bus sector can increase the power of urban residents by firmly putting transport in the public sphere; workers by increasing the incentives for collective action; and bus riders by prioritizing space for buses over cars. But these are only openings that require action to take advantage of the contradictions.  相似文献   

20.
A Norwegian White Paper on public transport paved the way for performance-based contracts for passenger rail. In order to estimate socially optimal economic incentives, we have calibrated and used a model which optimises public transport services and subsequently allows us to design incentives for operators that will induce them to provide the proper level of service. Our recommendations for intercity services have been implemented in the 2003 contract between the Norwegian State Railways and the Ministry of Transport and Communications.  相似文献   

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