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891.
This paper presents estimates of the rebound effect and other elasticities for the Canadian light-duty vehicle fleet using panel data at the provincial level from 1990 to 2004. We estimate a simultaneous three-equation model of aggregate demand for vehicle kilometers traveled, vehicle stock and fuel efficiency. Price and income elasticities obtained are broadly consistent with those reported in the literature. Among other results, an increase in the fuel price of 10% would reduce driving by ~2% in the long term and by 1% the average fuel consumption rate. Estimates of the short- and long-term rebound effects are ~8 and 20%, respectively. We also find that an increase in the gross domestic product per capita of 10% would cause an increase in driving distance of 2–3% and an increase of up to 4% in vehicle stock per adult. In terms of policy implications, our results suggest that: (1) the effectiveness of new fuel efficiency standards will be somewhat mitigated by the rebound effect and (2) fuel price increases have limited impacts on gasoline demand.
Philippe BarlaEmail:

Philippe Barla   is full professor at the economics department of Université Laval. He is currently the director of the research center GREEN and is a member of CDAT. He is conducting theoretical and empirical research on energy efficiency in the transportation sector. Bernard Lamonde   obtained his MA in economics in 2007 working on this project. He is working as an economist for Agence de l’efficacité énergique du Québec. Luis Miranda-Moreno   is professor at McGill Department of Civil Engineering and Applied Mechanics. He was post-doctoral student at CDAT when this research was carried out. His research interests include road safety, travel behaviour and demand modeling. Nathalie Boucher   holds a PhD in economics from Queens’ University. She is the executive director the CDAT a research center dedicated to improving knowledge about energy use in the Canadian private and commercial transportation sector.  相似文献   
892.
Dynamic traffic simulation models are frequently used to support decisions when planning an evacuation. This contribution reviews the different (mathematical) model formulations underlying these traffic simulation models used in evacuation studies and the behavioural assumptions that are made. The appropriateness of these behavioural assumptions is elaborated on in light of the current consensus on evacuation travel behaviour, based on the view from the social sciences as well as empirical studies on evacuation behaviour. The focus lies on how travellers’ decisions are predicted through simulation regarding the choice to evacuate, departure time choice, destination choice, and route choice. For the evacuation participation and departure time choice we argue in favour of the simultaneous approach to dynamic evacuation demand prediction using the repeated binary logit model. For the destination choice we show how further research is needed to generalize the current preliminary findings on the location-type specific destination choice models. For the evacuation route choice we argue in favour of hybrid route choice models that enable both following instructed routes and en-route switches. Within each of these discussions, we point at current limitations and make corresponding suggestions on promising future research directions.  相似文献   
893.
Agent-based microsimulation models of transportation, land use or other socioeconomic processes require an initial synthetic population derived from census data, conventionally created using the iterative proportional fitting (IPF) procedure. This paper introduces a novel computational method that allows the synthesis of many more attributes and finer attribute categories than previous approaches, both of which are long-standing limitations discussed in the literature. Additionally, a new approach is used to fit household and person zonal attribute distributions simultaneously. This technique was first adopted to address limitations specific to Canadian census data, but could also be useful in U.S. and other applications. The results of each new method are evaluated empirically in terms of goodness-of-fit.  相似文献   
894.
On the capacity of isolated, curbside bus stops   总被引:2,自引:0,他引:2  
The maximal rates that buses can discharge from bus stops are examined. Models were developed to estimate these capacities for curbside stops that are isolated from the effects of traffic signals. The models account for key features of the stops, including their target service levels assigned to them by a transit agency. Among other things, the models predict that adding bus berths to a stop can sometimes return disproportionally high gains in capacity. This and other of our findings are at odds with information furnished in professional handbooks.  相似文献   
895.
This paper analyses whether the decision to commute by car is influenced by built environment characteristics of residential neighbourhoods and, more especially, of work locations, taking into account interdependencies between household partners. It shows that the residential environment only affects car use among single-earners. Conversely, for all commuters, but in particular for dual-earners, characteristics of the work location affect whether they commute by car. Even in dual-earner households with two cars, work environment plays a role. We found that in cases of dual-earners with only one car, the partners with the longest commuting distances and the lowest density work locations are most likely to commute by car. Moreover, in households with young children, men are more inclined to leave the car at home. Other features relating to work also affect car commuting, including work flexibility and, especially, possession of a company car. We conclude that future policies aimed at reducing car use should place greater focus on work factors.  相似文献   
896.
A Traction Control System (TCS) is used to avoid excessive wheel-slip via adjusting active brake pressure and engine torque when vehicle starts fiercely. The split friction and slope of the road are complicated conditions for TCS. Once operated under these conditions, the traction control performance of the vehicle might be deteriorated and the vehicle might lack drive capability or lose lateral stability, if the regulated active brake pressure and engine torque can’t match up promptly and effectively. In order to solve this problem, a novel coordinated algorithm for TCS is brought forward. Firstly, two brake controllers, including a basic controller based on the friction difference between the two drive wheels for compensating this difference and a fuzzy logic controller for assisting the engine torque controller to adjust wheel-slip, are presented for brake control together. And then two engine torque controllers, containing a basic PID controller for wheel-slip control and a fuzzy logic controller for compensating torque needed by the road slope, are built for engine torque control together. Due to the simultaneous and accurate coordination of the two regulated variables the controlled vehicle can start smoothly. The vehicle test and simulation results on various road conditions have testified that the proposed method is effective and robust.  相似文献   
897.
Vehicle Dynamics Estimation Using Kalman Filters   总被引:1,自引:0,他引:1  
This paper deals with the application of stochastic state estimators in vehicle dynamics control. It is often unrealistic to assume that all vehicle states and the disturbances acting on it can be measured. System states that cannot be measured directly, can be estimated by a Kalman Filter. The idea of the Kalman filter is to implement a model of the real system in an on-board computer in parallel with the system itself. This paper will give 3 examples of this principle applied to automotive systems.  相似文献   
898.
Application of Optimal Control Theory to Inverse Simulation of Car Handling   总被引:5,自引:0,他引:5  
The application of Optimal Control Theory to time-optimal inverse simulation of car handling was investigated. Time-optimal inverse simulation of car handling involves the calculation of driver actions required to perform specified manoeuvres, in as short a time as possible. Driver actions consist of time-histories of front wheel steer rate and longitudinal force. Optimal time-histories of these quantities were calculated using the Gradient method after formulating the problem as one of optimal control. Simulation results are presented for two different cars performing similar lane-changes. These results show significant differences in necessary driver actions for different cars and demonstrate the suitability of the approach taken.  相似文献   
899.
This paper examines what is becoming the new order of maritime shipping, the transnational corporation. By combining the flags of convenience with crews of convenience, these corporations have become entiitcs with an existence above and beyond the nation-state in which they operate. Factors contributing to and problems resulting from this maritime structure are discussed. Possible resons for scholarly neglect of this area in the U.S.A. are suggested.  相似文献   
900.
Between 1980 and 1989 container TEUs handled at all world ports increased by a factor of 2.11. On the East Coast of North America, the growth factor was only 1.69; on the West Coast, 2.23. These growth factors, when multiplied by the 1980 TEU volume at individual North American ports, give 1989 expected performance levels for the ports. Comparing the expected performance to the actual, it is found in the Canadian context that the big winner is Vancouver; the big loser is Saint John. Halifax and Montreal have outperformed their nearest US East Coast rivals but have not performed as well as southern ports on the Altantic Seaboard. These and other comparisons are made in order to describe how Canadian container ports have performed in the decade of the 1980s. The paper then speculates on how the ports will do in the future, based on a discussion of five factors: port facilities; inland transportation connections; shipping lines serving the ports; demand for container shipping; and legal arrangements between the United States and Canada.  相似文献   
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