共查询到20条相似文献,搜索用时 15 毫秒
1.
Kenneth F.D. Hughey Geoffrey N. Kerr Ross Cullen 《Transportation Research Part D: Transport and Environment》2011,16(8):575-578
Based on a public survey of registered voters, we explore four options for internalising the social and environmental costs of road transport. The options were presented together with generalised factual information about their benefits and costs. Respondents are highly supportive of fuel use efficiency standards and exhaust gas quality standards, with lesser support for proposed initiatives of road user charges and speed reduction. Demographic analysis of responses enables identification of those who might favour or oppose particular options. In this case women are identified as being strongly supportive of the speed reduction option. 相似文献
2.
The paper reports the results of a series of studies conducted to enable the London Planning Advisory Committee to provide advice on strategic transport policy for London. The analytical approach combined the use of an area-based, multi-modal strategic model (LAM) and professional judgment. The performance of LAM as a basis for providing rapid advice on complex issues in transport policy is assessed.The resulting policy advice advocated a coherent approach, involving new infrastructure, particularly for rail; improved management of the road and public transport networks; the use of subsidy to enhance public transport service levels; and road user charges to reduce the impact of private vehicles on congestion and the environment. Road user charges emerged as the pivotal issue in the policy; the paper discusses their role, and the questions which still need to be resolved before they can be implemented.The main message of the study is that no one element of transport policy can tackle London's problems alone; an integrated policy in which infrastructure provision, management and pricing are used to complement one another is shown to be far more effective. 相似文献
3.
文章分析了工程项目成本管理存在的问题,从管理人员、成本控制要素、人工费、材料费、机械使用费、项目管理费等方面提出健全项目成本管理体制的措施。 相似文献
4.
Le Minh Kieu Ashish Bhaskar Paulo E. M. Almeida Nasser R. Sabar Edward Chung 《先进运输杂志》2016,50(8):1972-1989
Timed transfer coordination in public transit reduces passenger transfer time by providing seamless interconnected transfers. The problem arises when a Receiving Vehicle (RV) arrives to the transfer stop before a Feeding Vehicle (FV) carrying transferring passengers. Timed transfer coordination in operational control dynamically decides whether a RV is held at the transfer stop to allow transfers, or departs as scheduled. While transfer demand is essential for implementing timed transfer coordination, this variable is generally not available in public transit because of the lack of passenger transfer plans. The problem of acquiring this variable in real‐time has also received limited attention in the related literature. This paper proposes a new method to dynamically predict the transfer demand. We anticipate the transferring probability from each individual passenger by examining historical travel itineraries. Three different types of models (simple analytical, statistical, and computation intelligence model) are developed to forecast the number of transferring passengers. Numerical experiments using observed Automatic Vehicle Location and Automatic Fare Collection data from South East Queensland, Australia show the accuracy and applicability of the proposed models in timed transfer coordination. Copyright © 2017 John Wiley & Sons, Ltd. 相似文献
5.
ABSTRACTCost overruns are an endemic feature of the provision of transport infrastructure worldwide. In recent decades, a considerable amount of studies has been devoted to assessing the magnitude and determinants of cost overruns in the transportation sector. However, the empirical findings are scattered between different strands of literature, ranging from the fields of construction engineering and management to that of applied economics. To shed light on the determinants of cost overruns in the execution of transport infrastructure projects, we conduct a systematic review of the empirical literature on the topic. Of the 945 articles retrieved, 26 articles published between 2000 and 2016 meet our inclusion criteria. For them, we describe the different empirical approaches, we provide a classification of the determinants employed in the analyses and summarise their impact on cost overruns. Finally, we suggest some directions for further research in the field. 相似文献
6.
AbstractThe European railway market has gone through a period of liberalization over the last two decades. The liberalization of the railway market has also affected port-related railway transport. Efficient port-related transport chains are key in the competition among ports, however providing this efficiency is to a large extent a coordination challenge. Many forms of coordination are needed to ensure that the railway chain operates efficiently, including the bundling of cargo, and good organization between railway companies, terminal operators and the infrastructure managers to realize an efficient use of assets. From the literature, it appears that less attention has been paid to the economic organization of port-related railway transport in general, and specifically in the new liberalized institutional environment. The goal of this paper is to come up with a framework to better understand the issue of coordination in port-related railway chains in a liberalized institutional environment. This paper presents a conceptual framework rooted in Transaction Cost Economics (TCE). Based on an in-depth study into coordination in liberalized container railway market at the Port of Rotterdam, empirical illustrations are used to adjust the TCE approach toward a dynamic model influenced by Douglas North's theory on economic and institutional change. Empirics from the port of Rotterdam show that new players have entered the railway market and their role has changed. This paper shows that coordination of railway operations has become more complex after the regime change. From a port perspective, liberalization does not lead to an optimal allocation of resources in a process that is highly operationally interdependent. In the liberalized environment, coordination arrangements are necessary to enable efficient coordination of railway operations in Rotterdam. 相似文献
7.
There are recent evidence that air transport demand may not have a perfectly reversible relationship with income and jet fuel prices, as is assumed in most demand models. However, it is not known if the imperfectly reversible effects of jet fuel price are a result of asymmetries in the supply side, i.e., asymmetries in cost pass through from fuel prices to air fare, or of demand side behavioral asymmetries whereby people value gains and losses differently. This paper uses US time series data and decomposes air fare and fuel price into three component series to develop an econometric model of air transport demand that is capable of capturing the potential imperfectly reversible relationships and test for the presence or absence of reversibility. We find that air transport demand shows asymmetry with respect to air fare, indicating potential imperfect reversibility in consumer behavior. We also find evidence of asymmetry and hysteresis in cost pass-through from jet fuel prices to air fare, showing rapid increases in airfare when fuel prices increases but a slower response in the opposite direction. 相似文献
8.
Public Transport (PT) systems rely more and more on online information extracted from both operator’s intelligent equipment and user’s smartphone applications. This allows for a better fit between supply and demand of the multimodal PT system, especially through the use of PT real-time control actions/tactics. In doing so there is also an opportunity to consider environmental-related issues to approach energy saving and reduced pollution. This study investigates and analyses the benefits of using real-time PT operational tactics in reducing the undesirable environmental impacts. A tactic-based control (TBC) optimization model is used to minimize total passenger travel time and maximize direct transfers (without waiting). The model consists of a control policy built upon a combination of three tactics: holding, skip-stops, and boarding limit. The environmental-related measure is the global warming potential (GWP) using the life cycle assessment technique. The methodology developed is applied to a real life case study in Auckland, New Zealand. Results show that TBC could reduce the GWP by means of reduction of total passenger travel times and vehicle travel cycle time. That is, the TBC model results in a 5.6% reduction in total GWP per day compared with an existing no-tactic scenario. This study supports the use of real-time control actions to maintain a reliable PT service, reducing greenhouse gas emissions and subsequently moving towards greener PT systems. 相似文献
9.
This paper is part of ongoing research on incorporating environmental aspects in microscopic integrated land use/transport models. The long-term goal is to add scenario sensitivity for noise emissions in a new modeling suite. Therefore, as a first step, the influence of simulated car traffic noise on real rent prices in the study area in question is analyzed and compared to existing studies. It is shown that modeled noise values from the transportation model are able to explain significant impacts on rent prices when using a hedonic pricing regression. When using noise as a continuous variable, price discounts of 0.4% per dB(A) are found. A discount of up to 9.6% for particularly loud locations is estimated when noise is used as a categorical variable. Care should be taken when controlling for accessibilities that may correlate with noise. The results are in line with results of previous studies and confirm that environmental aspects can and should be considered in integrated models. 相似文献
10.
In many cities of the world, road space is increasingly contested. Growing vehicle numbers, traffic calming and the development of new infrastructure for more sustainable transport modes such as bicycles have all contributed to pressure on available space and conflicts over the allocation of space. This paper provides the first assessment of urban transport infrastructure space distribution, distinguishing motorized individual transport, public transport, cycling and walking. To calculate area allocation, an assessment methodology was developed using high-resolution digital satellite images in combination with a geographical information system to derive area measurements. This methodology was applied to four distinctly different city quarters in Freiburg, Germany. Results indicate that space is unevenly distributed, with motorized individual transport being the favoured transport mode. Findings also show that if trip number to space allocation ratios are calculated, one of the most sustainable transport modes, the bicycle, is the most disadvantaged. This suggests that area allocation deserves greater attention in the planning and implementation of more sustainable urban transport designs. 相似文献
11.
Some scholars consider that today’s market conditions are in favor of the Northern Sea Route (NSR) rather than the Suez Canal Route (SCR). However, the number of bulk carriers using the NSR remains extremely limited, despite higher fuel prices since 2009 and subsequent significant fuel savings. In 2013, there were 53 transits via the Arctic, out of which 27 by oil tankers and 6 by bulk carriers. In this article we show that this result might be attributable to a factor, which is not considered in most studies: the spot freight rate to fuel ratio which governs ship owners’ decisions regarding the sailing speed. Due to a low ratio since 2011, the speed of vessels on the SCR is at its lowest level, and potential NSR fuel savings are too limited to provide a viable alternative. We further argue that, contrary to most studies, internalizing NSR environmental benefits marginally improves the attractiveness of the NSR. 相似文献
12.
This paper reports the insights into environmental impacts of the ongoing transformative land use and transport developments in Greater Beijing, from a new suite of dynamic land use, spatial equilibrium and strategic transport models that is calibrated for medium to long term land use and transport predictions. The model tests are focused on urban passenger travel demand and associated emissions within the municipality of Beijing, accounting for Beijing’s land use and transport interactions with Tianjin, Hebei and beyond. The findings suggests that background trends of urbanization, economic growth and income rises will continue to be very powerful drivers for urban passenger travel demand across all main modes of transport beyond 2030. In order to achieve the dual policy aims for a moderately affluent and equitable nation and reducing the absolute levels of urban transport emissions by 2030, road charging and careful micro-level coordination between land use, built form and public transport provision may need to be considered together for policy implementation in the near future. 相似文献
13.
Western literature abounds with powerful imagery of mobility and travel, extolling the richness of experience and learning that can only happen along the way. The more common policy and research contexts consider travel and mobility as an important means to an end, valued relative to the destination activity. This review builds on the research that considers on-the-way benefits in order to expand this perspective as a part of transport studies. The question posed is if there is a place to evaluate mobility as a life-enhancing activity in its own right, directly contributing to the capacity for autonomy and freedom of choice that are central elements of personal well-being. Motility or mobility capital, defined as the capacity for mobility, offers a theoretical context for this purpose. The literature has adopted motility for its ability to broaden the understanding of mobility choices, by structuring a role for material, human, social and cultural capital as contributing to an individual’s capacity for mobility. The context of individual capital implies that motility holds value not only as an input to mobility choices, but also through its exchange value with other forms of capital, thereby promoting broader contexts for human flourishing. Therefore, motility has value as a policy objective for its contribution to individual well-being and this article further argues that it is through mobility experiences that this type of capital can be advanced. 相似文献
14.
A common policy for reducing particulate matter concentrations in the European Union is the introduction of Low Emission Zones (LEZs), which may only be entered by vehicles meeting predefined emission standards. This paper examines the effectiveness of LEZs for reducing PM10 levels in urban areas in Germany and quantifies the associated health impacts from reduced air pollution within the zones. We employ a fixed effects panel data model for daily observations of PM10 concentrations from 2000 to 2009 and control, inter alia, for local meteorological conditions and traffic volume. We apply the regression outputs to a concentration response function derived from the epidemiological literature to calculate associated health impacts of the introduction of LEZs in 25 German cities with 3.96 million inhabitants. Associated uncertainties are accounted for in Monte-Carlo simulations. It is found that the introduction of LEZs has significantly reduced inner city PM10 levels. We estimate the total mean health impact from reduced air pollution in 2010 due to the introduction of stage 1 zones to be ∼760 million EUR in the 25 LEZ cities in the sample, whereas total mean health benefits are ∼2.4 billion EUR for the more stringent stage 2 zones when applied in the same cities. 相似文献
15.
Much Ado about Nothing? - An analysis of economic impacts and ecologic effects of the EU-emission trading scheme in the aviation industry 总被引:1,自引:0,他引:1
Jan Vespermann Andreas Wald 《Transportation Research Part A: Policy and Practice》2011,45(10):1066-1076
From 2012 on, all CO2 emissions from flights departing from or arriving at airports within the European Union have to be offset. We analyze the economic and ecological impacts that are caused by an inclusion of the aviation industry into the proposed emissions trading scheme (ETS). Building on the now fixed system design we employ a simulation model to estimate the impacts of the scheme. Our results indicate that financial impacts are highly dependant on external settings, such as allowance prices and demand growth. We show that the financial burden on the aviation industry will be rather modest in the first years after the introduction of the system and therefore induce only low competition distortions. Likewise, emission reductions within air transportation will be comparably low. While aviation will induce a decline of emissions in other sectors, significant absolute reductions within air transportation can only be reached by a more restrictive system design. 相似文献
16.
文章基于当前广西公路勘察设计质量和工程造价现状,分析了公路工程勘察设计质量和造价控制方面存在的主要问题,提出了提高勘察设计质量、控制工程造价的对策。 相似文献
17.
The interdisciplinary research project AviClim (Including Aviation in International Protocols for Climate Protection) has explored the feasibility for including aviation’s full climate impact, i.e., both long-lived CO2 and short-lived non-CO2 effects, in international protocols for climate protection and has investigated the economic impacts. Short-lived non-CO2 effects of aviation are NOx emissions, H2O emissions or contrail cirrus, for instance.Four geopolitical scenarios have been designed which differ concerning the level of international support for climate protecting measures. These scenarios have been combined alternatively with an emissions trading scheme on CO2 and non-CO2 species, a climate tax and a NOx emission charge combined with CO2 trading and operational measures (such as lower flight altitudes). Modelling results indicate that a global emissions trading scheme for both CO2 and non-CO2 emissions would be the best solution from an economic and environmental point of view. Costs and impacts on competition could be kept at a relatively moderate level and effects on employment are moderate, too. At the same time, environmental benefits are noticeable. 相似文献
18.
A bi-objective bi-level signal control optimization for hazardous material (hazmat) transport is considered to assess trade-offs between travel cost and environment impacts such as public risk exposure. A least maxi-sum risk model with explicit signal delay is presented to determine generalized travel cost for hazmat carriers. Since the bi-level signal control problem is generally a non-convex program, a bundle method using generalized gradients is proposed. A bounding strategy is developed to stabilize solutions of the bi-level program and reduce relative gaps between iterations. Numerical comparisons are made with other risk-averse models. The results indicate that the proposed bi-objective bi-level model becomes even amiable to signal control policy makers since provides flexible solutions whilst is acceptable to carriers since takes account of travel delay at signal-controlled junctions. Moreover, the trade-offs between public risk and generalized travel costs are empirically investigated among different risk models with a variety of weights. As a result, the proposed model consistently exhibits highly considerable advantage on mitigation of public risk whilst incurred less cost loss as compared to other alternatives. 相似文献
19.
Starting from the intuition that people with high environmental concern have a better perception of public transport and therefore a better perception of the utility of public transport, we construct a theoretical model in which the effect of environmental concern on mode choice habits is mediated by the indirect utility of travel. Travel procures the direct utility of providing access to activities, but it also offers an indirect utility that is inherently personal and perceptual. We approach the indirect utility of public transport by measuring perceptions of time and feelings. The indirect utility of the car is approached by measuring affective and symbolic motives. Taking into account car use habits and habits of public transport use, the results show that people who have a high environmental concern perceive public transport use as easier, more useful and more pleasurable than people who do not have that environmental motivation. Such positive attitudes foster public transport use. Conversely, low environmental concern generates non-instrumental motives for car use, such as affective and symbolic motives. However, the relationship between affective and symbolic motives and car use habits is not robust. We can conclude that environmental concern influences mode choice habits and that the effect is partially mediated by perceptions and feelings towards public transport but not significantly by affective and symbolic motives for car use. 相似文献
20.
Internalisation of the external costs of transport is currently the subject of much debate. Estimation of costs such as those of pollution and congestion is a primary element in any strategy involving policies for use in the internalisation of these costs. The objective of the TRENEN II STRAN project, funded by the EU, was to develop a methodology for estimation of the marginal external costs of transport. The model developed during the project was used in a series of case studies. One of the case studies, that conducted for Dublin, is reported in this paper. A brief summary of the TRENEN approach is presented followed by the results for Dublin produced from policies such as Do Nothing, Uniform pricing (internalising external costs by means of fuel taxation), Congestion Pricing (cordon pricing) and a first-best policy, the Full Optimum where one assumes that the policy maker has perfect pricing instruments available. As one would expect, the model shows that the greatest reduction in traffic level and external costs would occur if it were possible to introduce a highly differentiated and sophisticated pricing system. Increased taxation on fuel is not an efficient policy as it does not address the marginal external costs of congestion in a way that time-differentiated road-use pricing would. The results from testing of the different measures are interesting particularly those relating to parking and the way in which residents within the CBD and commuters to the CBD are dealt with. This revised version was published online in June 2006 with corrections to the Cover Date. 相似文献