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Felix Caicedo 《Transportation Research Part D: Transport and Environment》2010,15(4):228-234
The time spent searching for free parking spaces can produce considerable environmental pollution. Information on parking availability can be a powerful instrument for reducing these search costs. This paper develops a demand assignment model to evaluate the benefits of manipulating information with the objective of reducing the time and distances involved in finding a parking-place; including the walking distances involved. Using the full search procedure it was found that improvements of some 10% in efficiency could be achieved, but only at high computational costs. A genetic algorithm was programmed that increases the possibility of finding the optimum information conditions that can be translated into lower emissions of toxic greenhouse gases. 相似文献
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Maarten Messagie Nele Sergeant Surendraprabu Rangaraju Javier San Felix Forner Luis Oliveira Thierry Coosemans 《运输规划与技术》2015,38(3):335-346
The European Clean Vehicle Directive was introduced in 2009 to create an obligation on public authorities to take into account the impact of energy consumption, carbon dioxide (CO2) emissions and pollutant emissions into their purchasing decisions for road transport vehicles. This should stimulate the market for clean and energy-efficient vehicles and improve transport's impact on environment, climate change and energy use. Therefore the so-called ‘Operational Lifetime Cost’ of a vehicle is calculated, divided into the cost for energy consumption, CO2 and pollutant (nitrous oxide, particulate matter, non-methane hydrocarbons) emissions. In Belgium, a different methodology has been developed to calculate the environmental impact of a vehicle, called ‘Ecoscore’, based on a well-to-wheel approach. More pollutants are included compared to the Clean Vehicle methodology, but also indirect emissions are taken into account. In this paper, both methodologies are compared and used to analyze the environmental performance of passenger cars with different fuel types and from different vehicle segments. Similar rankings between both methodologies are obtained; however, the large impact of energy use (and CO2 emissions) in the Clean Vehicle methodology disadvantages compressed natural gas cars, as well as diesel cars equipped with particulate filters, compared to the Ecoscore methodology. 相似文献
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Felix Creutzig Dongquan He 《Transportation Research Part D: Transport and Environment》2009,14(2):120-131
Urban car transportation is a cause of climate change but is also associated with additional burdens such as traffic congestion and air pollution. Studies of external costs and potential impacts of travel demand management help to define policy instruments that mitigate the damaging impact of transportation. Here, we analyze different externalities of car transportation in Beijing and show that social costs induced by motorized transportation are equivalent to about 7.5–15.0% of Beijing’s GDP. Congestion and air pollution contribute the most with climate change costs being the most uncertain. We show that a road charge could not only address congestion but also has environmental benefits. The paper investigates the role of demand elasticities and demonstrates that joint demand and supply-side policies provide considerable synergies. 相似文献
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Felix Creutzig 《运输评论》2016,36(3):341-360
Scenarios of low-carbon transport demonstrate that a vast range of different outcomes is possible and contingent on policy, technology and cultural developments. But a closer look indicates that different schools of thought suggest possible pathways diverging in their fine structure. This perspective reveals how three different scientific communities — integrated assessment modelers, transport-sector modelers, and place-based modelers — emphasize distinct solution domains. While integrated assessment models focus on fuel composition, transport-sector models put slightly higher emphasis on efficiency measures; in turn place-based research specifies idiosyncratic behavioral and infrastructural mitigation options that are likely to be beneficial in realizing local co-benefits. These specific local approaches could mitigate urban transport emissions by 20–50%, higher than that revealed in aggregate global models. We discuss differences in approach, possibilities for reconciliation, and the implications of normative assumptions. Targeted three-directional interactions would foster comprehensive understanding of possible low-carbon transportation futures. 相似文献
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Ali Asadi Lari Davood Younesian Felix Schmid 《Vehicle System Dynamics: International Journal of Vehicle Mechanics and Mobility》2007,45(4):359-373
A range of tangential forces is generated within the contact patch when a wheelset moves on the rail. These forces are intensified when incorporating curved tracks and motored axle rail vehicles [Arrus, P., de Pater, A.D. and Meyers, P., 2002, The stationary motion of a one-axle vehicle along a circular curve with real rail and wheel profiles. Vehicle System Dynamics, 37(1), 29-58]. The wheelset is subject to flange contact if an unbalanced force remains in a curve towards the high rail gauge face. The resultant force in the transverse direction includes the lateral force, the radial force, and the creep forces in addition to the effect of the frequent wheelset displacement due to the kinematic oscillation [Iwnicki, S., 2003, Simulation of wheel-rail contact forces. Fatigue Fracture Engineering Material Structure, 26, 887-900]. This article has focused on a potential variation in some of the forces cited when the wheelset is subject to backward and forward movements. A severe wear rate observed within the wheel flange region in Iranian Railways was investigated by operating a test bogie on a curvaceous track. An obvious improvement in the wear rate and wear pattern of the wheels was attained when the second test bogie encountered a bogie direction reversal procedure. This enhancement is considered in this article from the force analysis standpoint. 相似文献
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Felix Caicedo 《Transportation Research Part C: Emerging Technologies》2009,17(1):56-68
Two different ways to manage availability information in parking facilities were evaluated in this article. First, in level 4 PARC systems (Parking Access and Revenue Control), when occupancy percentages for all garage levels are above 90% and 95%, the information on variable message sign (VMS) panel will indicate that there are no free spaces – censoring information. In this article, zoning is understood as the second information management tool; it consists of placing vehicle detection systems at intermediary points around the facility in such a way as to separate it into internal zones. It is a variation applicable to facilities with level 2 PARC systems, such as those in shopping centres, where a modification of the vehicle counting algorithm in the main program of the PARC system allows the determination of the number of free spaces in specific zones within the parking facility. According to the simulations that were carried out after testing an existing choice model, level 4 PARC systems are sufficiently effective in small facilities; the option of preparing “false” information when 5 or 10 free spaces are left on a garage level in order to influence user decisions has few practical repercussions. However, the separation into internal zones proposed for level 2 PARC systems shows a 16.2% reduction in search time. 相似文献
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Due to the potential of automated vehicles to offer a multitude of advantages to the travelers and therefore influence their daily routines, it is essential to monitor the public’s opinion on this particular technological development. The goal of a number of surveys in recent years was therefore not only to elicit the general acceptance of the technology but to additionally explore when, how and why respondents were inclined to make use of it. This is the first literature review on surveys regarding automated vehicles with the intention to investigate the various methods currently being applied and the conclusions they lead to. In addition to comparing the general results in terms of the distributions of the response variables, the surveyed explanatory variables are categorized and analyzed according to their influence in different experiments. Based on these investigations, this review identifies research gaps that can be addressed in future experiments. 相似文献
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AbstractThe aim of this paper is to measure ‘overall’ success of a public private partnership (PPP) transport projects using four case studies. All four case studies are PPP toll roads from four different EU countries (UK, Spain, Portugal and Greece). The case studies have been analysed using a manual Qualitative Comparative Analysis approach. According to the paper, three different perspectives have been used to measure the success of a project, that is, project management perspective, stakeholder perspective and contract management perspective. The ‘overall’ success has then been deduced by bringing these three perspectives together as a holistic approach. The findings are presented in the form of a matrix and the final outcome of the paper shows a simple methodological approach that can be used to measure success of a PPP transport project. Since the study takes more of a qualitative approach, researcher bias and perceptions have a major role to play in the final outcome. However, to reduce ‘biasness’, quantitative measures have also been used to quantify the Key Performance Indicators and performance measures in the case studies. It is hoped that the study makes a valid contribution to the areas of transport PPPs and performance measurement. 相似文献
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Hans Michiels Inge Mayeres Luc Int Panis Leo De Nocker Felix Deutsch Wouter Lefebvre 《Transportation Research Part D: Transport and Environment》2012,17(8):569-577
This article employs an optimized impact pathway approach to marginal external health costs that relies on high-resolution dispersion models calibrated for Belgium and the surrounding areas. Per tonne, the MEHCPM2.5 is found to be many times larger than MEHCNOx, which is currently negative. Further, the impact of Belgian PM2.5 emissions in the immediate area of generation is significantly larger than the impact on more distant areas; the opposite is true for NOx. The MEHCs of both pollutants are predicted to increase in the coming years. Further analysis of the impacts of PM2.5 and NOx reveals that, on average, modern gasoline vehicles outperform their diesel counterparts as far as future emissions are concerned. This contrasts with findings for 2007, which suggested that Euro 5 diesels had fewer associated health costs because of the potential for ozone reduction offered by their NOx emissions. 相似文献
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