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1.
Transportation - Urban growth originates multiscale spatial patterns, such as those of transportation networks. Here, the public transportation network (PTN) of the city of Lisbon is analysed from... 相似文献
2.
The application of public–private partnerships (P3’s) in the transportation sector has grown in popularity worldwide. Despite this important shift in the provision of transportation service, there are clear gaps in knowledge about the impacts of P3 projects, especially on emissions from transportation systems as a whole. Not only should policy makers evaluate the emissions impacts from P3 projects, but they should also think about innovative models that address or charge for emissions into P3 contracts. This addition to P3 contracts could provide a new solution to the long-existing property right paradox: who owns (is responsible for) emissions from transportation systems? This study attempts to fill the research gap by analyzing these innovative models. Using the road network of Fresno, California, as our case study, we offer a number of interesting insights for policy makers. First, average peak emissions costs range from 1.37 cents per mile (the do-nothing case) to 1.20 cents per mile (profit-maximizing cases) per vehicle. Although emissions costs from the P3 projects are lowest for the profit-maximizing cases, the system-wide emissions costs of these cases are highest because of spillover effects. Second, charging project owners for the emissions costs of P3 projects is not an effective way to reduce emissions or the total costs of travel, especially on a VMT basis. Instead, the public sector should implement emissions-included social cost-based price ceilings. When employing these limits, project owners could still be charged for the emissions costs. Finally, using total travel time as the only objective function for evaluating P3 projects can be misleading. Several P3 projects have shown better outcomes using total travel cost with the inclusion of emissions and fuel consumption costs, instead of using total travel time as the only objective function. 相似文献
3.
This paper has two objectives: (i) to introduce a new approach in order to gain widespread support for road pricing; and (ii) to develop a detailed social welfare analysis for road pricing schemes. We first describe our novel approach that stimulates public support for road pricing, which we refer to as an investment public–private partnership, or IP3. This approach returns a significant portion of the economic value created by road pricing back to the citizens who own the newly priced facility. We then present a social welfare framework that estimates the benefits and costs of using the IP3 approach on an urban transportation network. A P3 project’s impact on overall social welfare provides a more comprehensive evaluation criterion than the often-used Value for Money (VfM) analysis. Apart from several theoretical studies, a detailed social welfare analysis that includes all major P3 project stakeholders is absent from the literature. We use Fresno, California as our case study in order to conduct a welfare analysis on IP3s. Our results show that system-optimal tolling favors average users, but that government—and consequently taxpayers—should pay for costly tolling systems (negative profits). In contrast, unlimited profit-maximizing tolls raise substantial profits for government, for the infrastructure’s citizen-owners, and for the private sector, but the average user is worse off. From a social-welfare perspective, one should search for a Pareto improvement under which all major stakeholders are better off. Our estimates indicate that a mixed public and private tolling scheme offers such an improvement. 相似文献
4.
In the last decades, due to the population increase and the relative need of new land to cultivate, expand urban centers and develop transportation networks, most of the Italian natural protected areas are subject to different typologies of human pressures that generally cause habitat fragmentation. This process represents a major concern for biodiversity conservation and a key driver of species loss.The main purpose of this paper was to investigate levels of natural habitat fragmentation due to roads and railways networks in the Italian National Parks (INP S) through the use of an Infrastructural Fragmentation Index (IFI).All the operations (geospatial analysis, image classification, and fragmentation analysis) were performed using a Geographic Information System (GIS) software for elaborating a national database. The obtained results include an IFI value for each natural territorial unit inside any INP. Moreover, in order to highlight which are the INP S characterized by higher infrastructural fragmentations, an IFI weighted mean was calculated for each INP. These results represent important indicators for the prioritization of biodiversity conservation interventions and the planning of a INP S sustainable management. 相似文献
6.
Although inevitably there are grey areas, a distinction may be drawn between environmental disbenefits arising from vehicles which cause annoyance, such as noise, or loss of peace and quiet, vibration, visual intrusion, severance, and those which endanger life and limb. Legislation implemented to reduce either category will inevitably generate costs.It is suggested that in evaluating legislation relating to environmental nuisance, attempts should be made carefully to measure the benefits, while for legislation when life and limb is involved a cost-effectiveness approach should be adopted. Methods currently available to measure environmental nuisance arising from vehicles, for example opinion surveys, observing the effect of changes in some independent indicator, and simulation exercises are critically examined. Using evidence from the Urban Motorway Committee Reports, Noise Advisory Council, Transport and Road Research Laboratory surveys on the effect of traffic in selected High Streets, and the Realistic Environment Assessment Laboratory, Social and Community Planning Research ping-pong technique, studies of house price differentials, and estimates of willingness-to-pay for exclusion facilities, an attempt is made to highlight the dilemma that while benefits of environmental nuisance legislation should be carefully weighed against the anti-pollution costs, techniques currently available for measuring such benefits are very underdeveloped.Paradoxically there is a far more clear-cut procedure for valuing benefits of policies affecting life and limb. Official accident evaluation policy in the U.K. is described, and legislation affecting life and limb is examined.Finally, difficulties of effectively enforcing legislation of both environmental nuisance and life and limb categories are illustrated. 相似文献
7.
Urban green spaces provide various social and environmental benefits that strongly improve the quality of life in a city. Municipalities are responsible for maintaining their green spaces in order to preserve these potentials. This paper supports municipalities in planning the transportation and disposal logistics of the green waste that is produced by the maintenance activities. The approach combines ecological issues like the seasonality of green waste generation and different types of biomass with economically driven decision making. We show how to determine cost efficient transportation plans for the disposal logistics and how to capture the seasonality of green waste generation when booking capacities at disposal facilities. It is also shown how a municipality can select the disposal facilities to cooperate with in a competitive environment where facilities offer capacities at differing conditions, as is the case for disposal sites that dump the green waste and for conversion plants that use the biomass for producing renewable energy. We illustrate the approach using case data of a major city in Germany. 相似文献
8.
Advances in Information and Communication Technologies (ICT) allow the transportation community to foresee dramatic improvements for the incoming years in terms of a more efficient, environmental friendly and safe traffic management. In that context, new ITS paradigms like Cooperative Systems (C-ITS) enable an efficient traffic state estimation and traffic control. C-ITS refers to three levels of cooperation between vehicles and infrastructure: (i) equipped vehicles with Advanced Driver Assistance Systems (ADAS) adjusting their motion to surrounding traffic conditions; (ii) information exchange with the infrastructure; (iii) vehicle-to-vehicle communication. Therefore, C-ITS makes it possible to go a step further in providing real time information and tailored control strategies to specific drivers. As a response to an expected increasing penetration rate of these systems, traffic managers and researchers have to come up with new methodologies that override the classic methods of traffic modeling and control. In this paper, we discuss some potentialities of C-ITS for traffic management with the methodological issues following the expansion of such systems. Cooperative traffic models are introduced into an open-source traffic simulator. The resulting simulation framework is robust and able to assess potential benefits of cooperative traffic control strategies in different traffic configurations. 相似文献
9.
Transportation planning continues to expand beyond traditional engineering and economic performance measures toward a broader scope of impacts across space and society. However, the attitudes of transportation planners as they balance their expert knowledge against public insights are not well-understood. We test a two-dimensional attitudinal framework using survey data from 311 U.S. and Canadian transportation planners. We reveal four attitudinal categories using principal component analysis, and hypothesis testing shows significant differences in personal and institutional attributes across these categories. We discuss what our results mean for training and regulatory measures striving to influence planner attitudes before proposing future directions for research. 相似文献
10.
Abstract In this paper, a methodology for capturing the transit passenger’s point of view by using both rating and choice options is proposed. For this purpose, some discrete choice logit models are introduced; the models allow the probability of choice of some alternative transit services to be calculated, and the importance of each service aspect to be determined. The models are calibrated by using data collected by a survey in which a stated preferences experiment was proposed to a sample of passengers, and some judgements were expressed by them about their transit services, in terms of perceptions and expectations. The introduced methodology provides a relevant contribution from a practical viewpoint because it allows the identification of the most important aspects on overall service quality; it is useful to the transit operators for measuring service quality and for investing on the various service aspects in order to effectively improve transit services. 相似文献
11.
This paper sets out the rationale and structure of a tool for assisting policy-makers and practitioners to understand behavioural challenges and open up thinking on the design of effective ‘behaviour change’ interventions. The ‘Four Dimensions of Behaviour’ (4DB) framework is based on the theoretical and empirical research in a range of policy domains including transport and pro-environmental behaviour more generally. The 4DB framework characterises multifaceted behaviours along dimensions of actor, domain, durability and scope. Its application in workshop or structured settings opens up diverse and non-exclusive discussion on designing interventions to match salient behavioural characteristics. The use of the 4DB framework in the transport domain is demonstrated for travel behaviours of interest to policy-makers using examples of buying plug-in vehicles (PiVs), commuting by bicycle, eco-driving and making business trips by train. 相似文献
12.
Transportation - Public–private partnership (PPP) has been well acknowledged by many as an innovative approach to the procurement of public projects. In their long-term concession periods,... 相似文献
13.
The role of transport disadvantage in the social exclusion of low income and marginalised households and communities has received
increasing academic and policy interest over the last 10 years or so. Against a backdrop of studies that have predominantly
considered this issue within various national contexts, this paper offers a unique opportunity to compare different national context. The paper is informed by a commissioned study for the State of Victoria Department of Transport (Lucas,
Study of transport exclusion in the state of Victoria: It doesn’t have to be this way, 2008), which wished to draw lessons from the United Kingdom in order to promote a similar policy agenda for the State. It is the
authors’ contention that the issue of transport-related social exclusion is likely receive growing international policy recognition
in the context of global recession, associated local job losses and reduced disposable incomes, as well as the ageing structure
of most Western societies. The paper seeks to disseminate the important findings of our study about the potential for policy
transfer to other national and local contexts to a wider academic, policy and practitioner audience. 相似文献
14.
This study examines the adoption of a travel behaviour modification programme to encourage sustainable mobility and public bus usage. Students from four schools in Penang Island were recruited and divided into two groups: Group 1 (without incentives) and Group 2 (with incentives). In the experiment, after having a motivation session about sustainable transport, the respondents were asked to design their travel patterns for seven days. The next session gathered data about their actual travel and asked for feedback regarding the programme. The results demonstrate that incentives encouraged respondents to follow their plans for travel behaviour and public bus usage. The results highlight that their commitment to follow their travel plans were influenced by ethnicity, distance from home to school, travel time, and household income. The study offers some discussion regarding the implications of the results for strengthening sustainable mobility and encouraging public bus use among adolescents. 相似文献
15.
Abstract This paper develops a royalty negotiation model based on the operating quantity of Build, Operate, and Transfer (BOT) projects for both government and the private sector using a bi-level programming (BLP) approach. The royalty negotiation is one of many critical negotiation items of a concession contract. This study develops a royalty negotiation model to simulate the negotiation behavior of two parties, and derives the heuristic algorithm for the BLP problem. A number of factors are incorporated into this algorithm including the concession rate, the time value discount rate, the learning rate, and the number of negotiations. The paper includes a case study of the Taipei Port Container Logistic BOT Project. The results show that the two parties involved completed royalty negotiation at the sixth negotiation stage. The findings show that the government can receive a royalty from the concessionaire, calculated at 0.00386% of the operating quantity of this BOT project. Therefore, the royalty negotiation model developed here could be employed to explain negotiation behavior. 相似文献
16.
The objective of this study was to examine the psychological predictors of the intention to use public transport for three travel purposes: work or study, shopping, and leisure. An expanded version of the theory of planned behaviour (TPB) which contains overall image and past behaviour is used. Data were gathered through the survey of 392 residents living in the central parts of Kuala Lumpur in Malaysia. These data were analysed using the partial least squares technique. The results indicate that attitude and perceived behavioural control are significant predictors of the intention to use public transportation for various purposes. Further, they explain between 34.6% and 49.8% of the intention variance. By adding the overall image and past behaviour to the original predictors in the TPB, the explained variance, with regard to work or study, shopping, and leisure purposes, increased by 5.6%, 5.1%, and 6.8%, respectively. 相似文献
17.
Transportation - In the online published article, in figure 2 a value is missing in column 4. The correct figure is given in this correction. The original article has been corrected. 相似文献
18.
Air traffic in the UK has increased rapidly in the past two decades and is forecast to grow at a rate of 4.3% per annum between 1998 and 2020. The failure to develop the air traffic system in order to cope with this growth has had undesirable consequences, e.g. a rise in flight delays and near misses. Given the investment required in air traffic control systems to cater for this growth, the UK government in 2000 part privatized the National Air Traffic Services (NATS), the body in charge of the UK's airspace in a public–private partnership (PPP). The UK Airline Group acquired 46% of NATS and effective operational control, though the government retains a share in NATS and safety regulation is in the public sector. However, serious doubts about safety were raised during the debate on the PPP. Similar moves towards a commercial operation (i.e. corporatization) of air navigation services have been made in New Zealand and Canada over the past decade and these provide useful insights into the results of the corporatization process. This paper analyses the main issues surrounding the part privatization of NATS. First, it highlights the experience from New Zealand and Canada of the major issues involved in corporatized air navigation services in six different categories: funding, new technology and project management, safety, pricing regime, international opportunities, and customer responsiveness. The likely impacts for NATS given the lessons from New Zealand and Canada are considered. The UK government's provisions for the PPP and their implementation in the post‐PPP NATS are then outlined for these six categories. Finally, the 11 September 2001 terrorist attacks have had major impacts on air travel and their consequences for NATS in the six categories are highlighted. This paper concludes with some of the issues that need to be addressed to ensure the success of the PPP for NATS. 相似文献
19.
Rising levels of childhood obesity in the United States and a 75% decline in the proportion of children walking to school
in the past 30 years have focused attention on school travel. This paper uses data from the US Department of Transportation’s
2001 National Household Travel Survey to analyze the factors affecting mode choice for elementary and middle school children.
The analysis shows that walk travel time is the most policy-relevant factor affecting the decision to walk to school with
an estimated direct elasticity of −0.75. If policymakers want to increase walking rates, these findings suggest that current
policies, such as Safe Routes to School, which do not affect the spatial distribution of schools and residences will not be
enough to change travel behavior. The final part of the paper uses the mode choice model to test how a land use strategy—community
schools—might affect walking to school. The results show that community schools have the potential to increase walking rates
but would require large changes from current land use, school, and transportation planning practices.
Noreen C. McDonald
is an Assistant Professor at the University of North Carolina at Chapel Hill. Her research focuses on how the environment
affects children’s travel behavior. 相似文献
20.
A hybrid predictive control formulation based on evolutionary multi-objective optimization to optimize real-time operations of public transport systems is presented. The state space model includes bus position, expected load and arrival time at stops. The system is based on discrete events, and the possible operator control actions are: holding vehicles at stations and skipping some stations. The controller (operator) pursues the minimization of a dynamic objective function to generate better operational decisions under uncertain demand at bus stops. In this work, a multi-objective approach is conducted to include different goals in the optimization process that could be opposite. In this case, the optimization was defined in terms of two objectives: waiting time minimization on one side, and impact of the strategies on the other. A genetic algorithm method is proposed to solve the multi-objective dynamic problem. From the conducted experiments considering a single bus line corridor, we found that the two objectives are opposite but with a certain degree of overlapping, in the sense that in all cases both objectives significantly improve the level of service with respect to the open-loop scenario by regularizing the headways. On average, the observed trade-off validates the proposed multi-objective methodology for the studied system, allowing dynamically finding the pseudo-optimal Pareto front and making real-time decisions based on different optimization criteria reflected in the proposed objective function compounds. 相似文献
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