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1.
Peter K. Else 《运输评论》2013,33(4):291-309
Governments have rarely been content to leave the provision of public transport services entirely to the market. Competition has been regulated and increasingly services have been subsidized from public funds. However, the criteria for such subsidies have been a continuing source of debate. Economists have tended to emphasize efficiency criteria and advocated the use of cost‐benefit analysis, but, for a variety of reasons, in the U.K. at least, this approach does not seem to have played a major role in the allocation of subsidies. Others have advocated more needs‐based approaches. Whilst these have been tried, they also have their limitations. The first few sections of the paper, therefore, review the development of these approaches in the U.K. and consider their shortcomings from the point of view of deciding on transport subsidies. In the latter part of the paper it is suggested that developments in the appraisal of health care procedures, particularly in the use of cost‐utility techniques, indicate a possible alternative approach. The approach in the health context is outlined and it is demonstrated how it might be applied to the appraisal of local transport services.  相似文献   

2.
In the past few decades much research has been conducted on the increasing numbers of commuters taking up cycling to work. This modal shift has been encouraged by pro-cycling policies to increase the attractiveness of cycling and the construction of new cycling infrastructure. In Dublin, several policies have been applied such as a bike rental scheme, bicycle-purchasing schemes, reducing speed limits and the construction of segregated cycle lanes to promote cycling. This paper seeks to examine what, if any, impact these policies have had on cycling rates in Dublin. This paper compares census data from 2006 and 2011 to determine how cycling rates have changed and if the demographics of cyclists have changed in the city. The results presented in the paper show that cycling rates have increased in Dublin and that a greater percentage of females, those in higher age and socio-economic groups are cycling to work on a regular basis. The analysis presented in this paper identifies groups of individuals that have recently shifted to cycling to work, by identifying who these people are, policymakers can tailor strategies to target these groups to encourage others in these groups to take up cycling.  相似文献   

3.
Several decades of research on transit pricing have provided clear insights into how riders respond to price changes in both the transit and automobile sectors. For the most part, riders are insensitive to changes in either fare levels, structures, or forms of payments, though this varies considerably among user groups and operating environments. Since riders are approximately twice as sensitive to changes in travel time as they are to changes in fares, a compelling argument can be made for operating more premium quality transit services at higher prices. Such programs could be supplemented by vouchers and concessionary programs to reduce the burden of higher fares on low-income users. Also, cross-elasticity research suggests that higher automobile prices would have a significantly greater affect on ridership than lower fares. Most research on transit fare structures shows that the common practice of flat fares is highly inequitable, penalizing short-distance and off-peak users. Free fare programs have proven quite costly for each new transit user attracted and have rarely lured motorists to transit. Free fares limited to downtowns have been more successful than systemwide free fare programs. While prepayment schemes have met with success in the U.S. and Europe, honor fares have suffered from excessive revenue losses in at least one case in the U.S. Some of the more noteworthy fare policy successes in North America have been Bridgeport's combined pass-fare program, Allentown's deep discounts, Ottawa's major fare reduction and differentiation, and Columbus's substantial midday discount. As paratransit and other new transit alternatives to conventional bus continue to emerge, new, more differentiated fare practices can be expected in the future.  相似文献   

4.
A number of states have placed high-speed rail service on their institutional agendas in recent years. Analysis of why some states have been giving serious consideration to the possibility of high-speed rail service while other states have not examined economic and political forces, as well as the transportation problem environment and established transportation commitments. States paying serious attention to high-speed rail service tend to have large populations and large land areas, two of the most fundamental aspects of the transportation task environment.  相似文献   

5.
地下管线测漏仪中数据的采集和预处理   总被引:1,自引:0,他引:1  
在对管线渗漏信号进行分析的基础上 ,利用DSP芯片TMS32 0VC5 40 2和模数转换器CS5 36 0实现了数据的高精度采集。同时设计了基于渗漏信号特征的数字滤波器 ,对采集后的信号进行有效预处理。  相似文献   

6.
7.
Unlike school trips, the leisure activities of children and transport to these activities have received relatively little attention. Organized activities have increased and the immediate neighbourhood is not always the most appropriate or desirable area to play in or carry out various leisure activities. This paper presents findings from a nationwide survey in Norway that focus on children’s mobility. The results suggesting that a large proportion of children 6–12 years participate in organized leisure activities – sporting pursuits and music being the most popular and car is the main transport mode to these activities. The car share is higher than for school trips. The analysis indicates that children, particularly in these age groups, have parents with at least one car and who use the car for most purposes. Families who live in the larger cities have less access to a car than families living in other places, and this is reflected in the transport mode when children are escorted to leisure activities. Although distance to activities and children’s age are important for car-use, parents travel habits also have an impact on mode choice for these purposes.  相似文献   

8.
Industrialized countries have extensive experience with various transportation energy conservation measures and have been making steady progress in improving the efficiency of their transport sector. Less Developed Countries (LDCs) have also been making progress, but their experience in many aspects of transportation energy conservation is very limited. Development organizations have funded many transportation projects in developing countries, but the vast majority of these projects were designed to improve the transportation infrastructure. Very few transportation energy conservation projects have been implemented and decision-makers face a scarcity of information on effective strategies. This paper gives an overview of transportation projects in LDCs in order to identify those transportation energy conservation measures that offer the greatest potential for LDCs. Two case studies, from Tunisia and Costa Rica, are given to illustrate the issues involved in implementing transportation energy conservation measures in LDCs. Conclusions are drawn to suggest actions for developing countries and for development organizations.Acronyms DECAT Driver Energy Conservation Awareness Training - DSE Direccion Sectorial de Energia (Costa Rica) - GDP Gross domestic product - km Kilometer - LDCs Less Developed Countries - TOE Metric tonne of oil equivalent - USAID US Agency for International Development  相似文献   

9.
In this work, a sample of vehicles has been instrumented to measure of variables that influence vehicle noise emissions in Madrid. A circuit reproducing a normal travel pattern in large city is traveled by a fleet of vehicle models representing the fleets of cars in a European city. A sample of drivers covers the test track under different traffic conditions. Driving parameters and noise emitted have been recorded in each test and average values have been extracted. These data have been analyzed to define the noise emissions produced by a vehicle in real driving conditions and to identify the noisiest driving behaviors.  相似文献   

10.
Traditionally, many economists have examined the models and economics of urban taxi services under various types of regulation such as entry restriction and price control in an aggregate way. Only recently have we modeled urban taxi services in a network context. A realistic method has been proposed to describe vacant and occupied taxi movements in a road network and taxi drivers' search behavior for customers. A few extensions have been made to deal with demand elasticity and congestion effects together with development of efficient solution algorithms. Calibration and validation of the network taxi service models have been conducted towards their practical applications. This paper presents an overview of the research that has been carried out by the authors to develop network equilibrium models and solution algorithms for urban taxi services, and offers perspectives for future researches.  相似文献   

11.
Z. J. Haritos 《运输评论》2013,33(3):213-229
Abstract

In most economies, the ownership and control of state enterprises has been an important government policy instrument. This has been particularly true in the transportation sector in which governments have intervened extensively through the acquisition and creation of state enterprises. While the genesis of and rationale for transportation state enterprises have varied from country to country and even from time to time within each country, at present, most governments do exercise a significant degree of ownership and control in transportation. Some of these enterprises enjoy monopoly status and others are in competition with and behave similarly to their private sector counterparts.

Consequently, and in recent years, questions have been raised about government intervention in the market‐place as it relates to effective management control and accountability of state enterprises. Questions have also been raised about the continuing need for transportation state enterprises and some governments have promoted some form of divestiture (privatization).

This paper addresses the accountability and control of transportation state enterprises based on the Canadian experience. It discusses their role and policies related to diversification, financing and divestiture, and the need for development of a performance framework.  相似文献   

12.
This paper describes current light rail transit planning and operation in Canada's major cities and smaller communities. There are ten urban areas in Canada with 250,000 or more people. Two of these have light rail systems in operation, three have lines under construction and nine others are planning LRT systems.  相似文献   

13.
This paper analyses transport energy consumption of conventional and electric vehicles in mountainous roads. A standard round trip in Andorra has been modelled in order to characterise vehicle dynamics in hilly regions. Two conventional diesel vehicles and their electric-equivalent models have been simulated and their performances have been compared. Six scenarios have been simulated to study the effects of factors such as orography, traffic congestion and driving style. The European fuel consumption and emissions test and Artemis urban driving cycles, representative of European driving cycles, have also been included in the comparative analysis. The results show that road grade has a major impact on fuel economy, although it affects consumption in different levels depending on the technology analysed. Electric vehicles are less affected by this factor as opposed to conventional vehicles, increasing the potential energy savings in a hypothetical electrification of the car fleet. However, electric vehicle range in mountainous terrains is lower compared to that estimated by manufacturers, a fact that could adversely affect a massive adoption of electric cars in the short term.  相似文献   

14.
ABSTRACT

The benefits of autonomous vehicles (AVs) are widely acknowledged, but there are concerns about the extent of these benefits and AV risks and unintended consequences. In this article, we first examine AVs and different categories of the technological risks associated with them. We then explore strategies that can be adopted to address these risks, and explore emerging responses by governments for addressing AV risks. Our analyses reveal that, thus far, governments have in most instances avoided stringent measures in order to promote AV developments and the majority of responses are non-binding and focus on creating councils or working groups to better explore AV implications. The US has been active in introducing legislations to address issues related to privacy and cybersecurity. The UK and Germany, in particular, have enacted laws to address liability issues; other countries mostly acknowledge these issues, but have yet to implement specific strategies. To address privacy and cybersecurity risks strategies ranging from introduction or amendment of non-AV specific legislation to creating working groups have been adopted. Much less attention has been paid to issues such as environmental and employment risks, although a few governments have begun programmes to retrain workers who might be negatively affected.  相似文献   

15.
“Can a single car really absorb a traffic jam without making new jams?” In this paper, we focus on this frequently-discussed question, and have succeeded in making a theoretical framework of a driving technique how to absorb a traffic jam by using a minimal microscopic model. Jam-absorption driving comes from Beaty (Beaty, 1998, Beaty, 2013), and it is composed of a sequence of two actions termed the “slow-in” and “fast-out”. The “slow-in” is the action to avoid being captured by a jam and remove it by decelerating and taking a longer headway in advance. The “fast-out” is performed after the “slow-in”, and it is the action to follow the car in front without unnecessary time gaps by accelerating quickly. In our theoretical framework, we have represented the recipe of the actions such as the time–space points and the velocity. Moreover, we have clarified the condition of no secondary jams due to this driving, i.e., the condition that compression and expansion waves caused by this driving meet each other and disappear. Particularly, we have calculated how these waves propagates to the following cars and the point where and when they disappear. Besides, we have analyzed how this point moves in time–space diagrams by varying the timing to start the jam-absorption, and revealed that the pattern of this movement is not constant but changes greatly by the velocity-headway relationships. Furthermore, as a more realistic problem, we have formulated the driving for jam-absorption in two steps of deceleration, which brings rich patterns of collisions among compression and expansion waves.  相似文献   

16.
In this paper (nested) logit models that describe the combined access mode-airport-choice are estimated. A three level nested logit model is rejected. A two level nested logit model with the airport choice at the top level and the access mode choice at the lower level is preferred. From the estimation results, it is concluded that business travelers have a higher value of time than leisure travelers. In the (conditional) access mode choice, leisure travelers have a higher access cost elasticity (in absolute value), while business travelers have a higher access time elasticity (in absolute value). In general, access time is of large importance in the competition between airports in a region.  相似文献   

17.
《西部交通科技》2009,(3):47-52
西部地区国道主干线、省际通道已延伸到地形、地质条件复杂的特殊地理气候区和山岭重丘区,如沙漠、黄土、冻土、膨胀土、岩容等特殊地质地区,给交通建设、养护管理和生态环境保护造成极大困难。为解决这些技术难题,西部项目从勘测设计、施工、养护与管理、生态环境等方面开展系统研究,形成了特殊地质地区公路修筑成套技术,此项成果解决了技术难题,降低了工程造价,确保了工程建设的质量与进度。  相似文献   

18.
Abstract

Despite the proliferation of bus rapid transit (BRT) systems over the past few decades across developed and developing world cities, the impacts across these systems on the urban spatial development and property markets have not been comprehensively studied. The current paper attempts to fill this gap in the literature by reviewing the methodologies, underlying theories, and findings presented in the individual academic studies on BRT land-use and price impacts, mostly drawing on those that have focused on Latin American and Asian systems. The review shows that the land-use and value impacts have been less uniform across systems compared to such operational performance metrics as speed and travel time improvements. While predominantly relying on cross-sectional modeling techniques, the approaches used to evaluate land-use changes induced by the transit systems are not uniform either, with only some studies explicitly measuring changes in types of land use as opposed to simply land or rental price. The study also concludes that more rigorous evaluation is needed as to whether the BRT systems have improved accessibility for the populations that inhabited the corridors previously or whether, instead, the desired land value increases have in fact resulted in significant population displacement.  相似文献   

19.
The problems on scheduling and schedule co‐ordination usually have conflicting objectives related to user's cost and operator's cost. Users want to spend less time to wait, transfer and travel by public buses. Operators are interested in profit making by lesser vehicle operating cost and having a minimum number of buses. As far as level of service is concerned users are interested in lesser crowing while operators are concerned with maximizing profit and thus to have higher load factors. In schedule co‐ordination problems transfer time plays an important role. Users are interested in coordinating services with in acceptable waiting time whereas operators prefer to have lesser services and want to meet higher demands, which invariably increases waiting time. These problems have multiple conflicting objectives and constraints. It is difficult to determine optimum solution for such problems with the help of conventional approaches. It is found that Genetic Algorithm performs well for such multi objective problems.  相似文献   

20.
When operated at low speeds, electric and hybrid vehicles have created pedestrian safety concerns in congested areas of various city centers, because these vehicles have relatively silent engines compared to those of internal combustion engine vehicles, resulting in safety issues for pedestrians and cyclists due to the lack of engine noise to warn them of an oncoming electric or hybrid vehicle. However, the driver behavior characteristics have also been considered in many studies, and the high end-prices of electric vehicles indicate that electric vehicle drivers tend to have a higher prosperity index and are more likely to receive a better education, making them more alert while driving and more likely to obey traffic rules. In this paper, the positive and negative factors associated with electric vehicle adoption and the subsequent effects on pedestrian traffic safety are investigated using an agent-based modeling approach, in which a traffic micro-simulation of a real intersection is simulated in 3D using AnyLogic software. First, the interacting agents and dynamic parameters are defined in the agent-based model. Next, a 3D intersection environment is created to integrate the agent-based model into a visual simulation, where the simulation records the number of near-crashes occurring in certain pedestrian crossings throughout the virtual time duration of a year. A sensitivity analysis is also carried out with 9000 subsequent simulations performed in a supercomputer to account for the variation in dynamic parameters (ambient sound level, vehicle sound level, and ambient illumination). According to the analysis, electric vehicles have a 30% higher pedestrian traffic safety risk than internal combustion engine vehicles under high ambient sound levels. At low ambient sound levels, however, electric vehicles have only a 10% higher safety risk for pedestrians. Low levels of ambient illumination also increase the number of pedestrians involved in near-crashes for both electric vehicles and combustion engine vehicles.  相似文献   

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