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1.
Across the globe population structures are ageing and how older men and women interact with the transport system is increasingly important in maintaining a good quality of life and inclusion in society. The paper reviews three issues: the nature of older people’s interaction with the transport system by gender; older people’s attitude to travel; and the involvement of older people as road traffic casualties. Patterns of travel in the UK show that older people are heavily dependent on car use, but in the form of more frequent but shorter journeys than younger people. This is especially so for women over 70 years old who, as passengers, are very reliant on males to drive them. Attitudes suggest that there are few obstacles to public transport use, and most agree that bus travel is good, but convenience means many prefer cars. Involvement of older men and women in serious road traffic accidents show that they have lower killed and seriously injured (KSI) rates than 17–24 year old drivers. However, those aged over 70 years exhibit a trend of increasing KSI rates. Analysis of casualty rates of drivers by type of junction, manoeuvre and environmental conditions found that some gender-age groups are overrepresented in certain accident types, including higher serious accidents rates for men, and over representation of older women when driving in poor conditions and turning right and negotiating roundabouts, crossroads and T, Y and staggered junctions. Improvement in engineering design and driver training are suggested together with the need for a greater understanding of the transportation system needs of old and very old people.  相似文献   

2.
Choosing between the competing approaches to providing enhanced bus services requires the ability to predict the effects on patronage and overall benefits to society in terms of Value of Resources Consumed (VRC) of any proposed change. One common approach uses the Mohring model of 1972 and its successors to optimise one or more aspects of the supply of transit services given various level of demand. This paper simulates the operation of a simple circular bus route using the equations of a basic Mohring type model and a Decision Support System (DSS) to endogenise demand under the assumption that there is a fixed demand for travel but commuters can choose between the bus and private vehicle. The selected approach recognises that demand for a particular mode of travel is predicated on the speed of the vehicle in service which is itself determined by the demand for that vehicle (in this model or boarding and alighting time) rather than being determined exogenously. This creates an iterative feedback mechanism whereby changes to the attributes of the bus and car alter mode choice and the speed in service of the bus which, in turn, alters mode choice. The simulation is used to predict changes to patronage and VRC under scenarios regarding changes to the transport network (in terms of fares and running costs, frequency and spacing of bus stops) using parameters from both a Multinomial Logit (MNL) and a Mixed Multinomial Logit (MMNL). The results demonstrate that there are large differences in the size and, in some cases, direction of predicted changes to patronage, VRC and revenue, depending on whether the parameters of the MNL or MMNL model are used.  相似文献   

3.
国内高速公路养护维修作业区事故是交通管理部门亟待解决的一个问题。文中研究了国外高速公路养护维修作业区的事故规律,通过对国外文献中高速公路作业区事故危险因素分析法的综述,建立完善的作业区危险因素体系。结合事故数据,分析国内作业区事故特点,并有针对性地提出了安全管理对策。  相似文献   

4.
Road transport imposes negative externalities on society. These externalities include environmental and road damage, accidents, congestion, and oil dependence. The cost of these externalities to society is in general not reflected in the current market prices in the road transport sector.An efficient mobility model for the future must take into account the true costs of transport and its regulatory framework will need to create incentives for people to make sustainable transport choices. This paper discusses the use of economic instruments to correct road transport externalities, but gives relatively more weight to the problem of carbon emissions from road transport, as this is particularly challenging, given its global and long-term nature.Economics offers two types of instruments for addressing the problem of transport externalities: command-and-control and incentive-based policies.Command-and-control policies are government regulations which force consumers and producers to change their behaviour. They are the most widely used policy instruments. Examples include vehicle emission and fuel standards in the US as well as driving or parking restrictions in Singapore. The implementation cost of these instruments to the government is small. Although from an economic perspective these policies often fail to achieve an efficient market outcome, the presence of political constraints often make them the preferred option, in terms of feasibility and effectiveness.Economic theory shows how policies, which affect consumption and production incentives, can be used to achieve the optimal outcome in the presence of externalities. Incentive-based policies function within a new or an altered market. We first examine incentive-based policies, which cap the aggregate amount of the externality, such as carbon emissions, by allocating permits or rights to the emitters. The emitters are then free to trade their permits amongst them. The permit allocation mechanism is important-although market efficiency would be satisfied by an auction, political influences usually favour a proportional allocation based on historic emissions. We discuss EU ETS as an example of a cap-and-trade system, however, no such policy for CO2 emissions in road transport has been implemented anywhere in the world to date.Fiscal instruments are, like command-and-control, widely used in road transport, because they are relatively cheap and simple to implement. They include the use of taxes and charges in order to bridge the gap between private and the social costs and, in principle, can lead to an efficient market solution. Registration, ownership, fuel, emissions, usage taxes, and parking and congestion charges have been implemented in many countries around the world. On the other side of the spectrum, subsidies can be given to those scrapping old cars and buying fuel-efficient vehicles. Some cities, such as London, have implemented congestion charges and many states in the United States have introduced high occupancy lanes. Other interesting possibilities include pay-as-you-drive insurance and other usage charges. However, the size and scope of taxes and subsidies are determined by governments, and because of their imperfect knowledge of the market the outcome is still likely to be inefficient.Governments have many effective economic instruments to create a sustainable road transport model. These instruments can be used separately or together, but their implementation will be necessary in the nearest future.  相似文献   

5.
Road safety policies and automobile insurance contracts often use incentive mechanisms based on traffic violations and accidents to promote safe driving. Can these mechanisms improve road safety efficiently? Do they reduce asymmetric information between drivers and insurers and regulators? In other words, is there residual asymmetric information in observed distributions of accidents and infractions? We answer these questions in this article by reviewing recent theoretical and empirical results that rest on various data and methodologies. We present recent tests related to the identification of residual asymmetric information in road safety management and in automobile insurance contracting. We also propose a theoretical analysis of the foundations of point-record driver's licenses observed around the world.  相似文献   

6.
China’s Belt and Road (BR) initiative is expected to facilitate international trade between the countries involved. In this study, we review the special requirements of wine logistics and the market growth potential of wine consumption in China. A model minimizing generalized logistical costs is developed and applied to wine imports in China, so that the best candidate cities in which to locate transport gateways and distribution centers can be identified. Our analysis suggests that the most preferred gateways are Shanghai, Tianjin, Guangzhou, and Hong Kong, which all have similar delivery costs. In comparison, Beijing and Chongqing have much higher delivery costs, mainly because they do not have good access to marine transport and/or efficient domestic distribution networks. For long-distance intercontinental transport of large volumes of wine, marine shipping remains the only viable delivery mode. However, wine distribution within China extensively uses air, road, and water transport. Therefore, cities with excellent multi-modal transport services are better positioned to become wine logistics gateways. Our study also highlights the importance of value-added services and good government support, which are important factors that influence distribution costs and quality.  相似文献   

7.
对嵌入式实时系统VxWorks中的设备驱动程序开发进行了简要的介绍,讨论了VxWorks操作系统下的I/O系统和设备驱动程序、应用程序之间的关系。另外,结合作者开发PCI9054时统卡驱动程序的实际,讨论了VxWorks下PCI设备驱动程序的框架,并详细介绍了各个模块的具体实现。  相似文献   

8.
This chapter, following the results of the case studies analyzed in the Enact project, will identify and analyze the implications of the possible application of SMCP in PPP’s in the road sector. The main issues analyzed include SMCP revenue formation and its ability to finance the PPP. The paper will focus on market and competition issues like: 1) the problems due to mispriced substitutes; 2) the interdependencies between the tolls and the capacity of different road infrastructures when these are competing for the same demand; 3) since short run social marginal costs do not repay for the investments costs (except in special cases), in the case tolls should cover also the investment costs this will lead to totally different pricing schemes between roads in a same area, with problem of demand shift toward cheaper existing infrastructures, therefore increasing the problem of cost recovery. The incentives caused by the introduction of prices based on SMC’s are also investigated.  相似文献   

9.
Economic assessment of universally designed transport projects has not been studied in depth in the transport planning literature. Universal Design (UD) refers to the design of transport systems in a way that they are accessible to all users, irrespective of the users’ abilities. This definition of UD has not yet gained roots in the transport economic literature. The conventional thinking is that UD is for the few, i.e., the impaired, and given that they are few in numbers, UD projects will generally be unprofitable from a socioeconomic point of view because benefits will be low while investment costs will be too high. The objective of this paper is to prove the opposite: UD projects benefit all users of the facility, whether impaired or not, and the additional costs of implementing them are generally low; hence, their net present values are high and positive. We build on collaborative work between the Norwegian Public Roads Administration (NPRA) and the Institute of Transport Economics (TOI) aimed at creating guidelines for assessing the economic merits of UD projects. Therefore, in this paper, we: (1) define how UD is to be understood in the context of road and public transport; (2) describe the types of benefits and costs that accrue to users if UD projects are implemented; (3) address how the benefits and cost can be valued in monetary terms; and (4) using three different types of projects, demonstrate that UD projects are surprisingly profitable from a socioeconomic point of view. Finally, we address the implications of our findings and explain why governments need to be concerned with UD of transport systems.  相似文献   

10.
Dry port plays increasingly an important role in the integration of inland regions with seaports, and cross-border inland ports especially in the context of Belt and Road Initiative (BRI) originally proposed by China. This paper studies a logistics network connecting the inland regions by dry ports based on a two-stage logistical gravity model. First, a basic logistical gravity model is developed to analyze the radiated inland regions from dry ports, where the logistical quality of dry ports is calculated by principal component analysis. Second, considering mutual impacts among dry ports, seaports and cross-border inland ports, the influence of logistical gravity on the network is examined by using a coefficient based on the Ordered Weighted Averaging Operator in multi-attribute decision theory. An improved logistical gravity model is further developed to investigate the logistical connections among various ports (e.g. dry ports, seaports and cross-border inland ports; hub and feeder ports). Then, a hub-and-spoke network can be established. Dry ports are potential to connect to the Silk Road Economic Belt and the 21st-Century Maritime Silk Road. So a Chinese case is used to verify the proposed method. The strategies of embedding inland regions in the BRI are discussed based on the experimental studies.  相似文献   

11.
为定量评估交通运输方式转换对区域节能减排的贡献,以内河航道能力提升为重点,运用Logit模型计算内河航道能力提升后对铁路和公路货运量的分担率。根据能耗和排放相关参数分别确定运输方式转换前后所需能耗和所产生的CO_2排放量,对比分析内河航道能力提升对区域节能减排的贡献。以山东省小清河复航工程为例,采用所构建的计算模型进行分析,结果显示该项目的节能和CO_2减排量达32. 10%,表明内河航道能力提升对区域交通系统的节能减排效果显著。  相似文献   

12.
Despite European Union (EU) political support to identify the most feasible Motorways of the Sea, the final decision can only be made by Private Shipping Companies, which are operators of a unique stretch of the intermodal chain. This paper provides a multi-criteria decision method to identify the most suitable Motorways of the Sea taking into account the competitiveness of whole intermodal routes versus the alternative of road transport from the loader’s perspective. The analysis is carried out assuming a ‘many-to-many’ transport model. Firstly indexes of time and cost were defined and evaluated for every available route in the model in accordance with a multi-criteria decision matrix. Secondly, through a Monte Carlo simulation a sensitivity analysis was carried out in order to evaluate the influence on the results of the forecast assumed to construct the matrix. The results obtained are not only quantitative, but also qualitative. The development of intermodal routes via Motorways of the Sea is especially relevant for the peripheral EU countries. Due to the relevance of the freight flow between France and Spain and the congestion of their connections through the Pyrenees, the method proposed was applied to the analysis of this particular case  相似文献   

13.
Traditional economic analysis techniques used in the assessment of Public Private Partnership (PPP) projects are based upon the assumption that future cash flows are fully deterministic in nature and are not designed to account for risks involved in the assessment of future returns. In reality, many of these infrastructure projects are associated with significant risks stemming from the lack of knowledge about future cost and benefit streams. The fundamental premise of the PPP concept is to efficiently allocate risks between the public and the private partner. The return based on deterministic analysis may not depict a true picture of future economic outcomes of a PPP project for the multiple agencies involved. This deficiency underscores the importance of risk-based economic analysis for such projects. In this paper, the authors present the concept of Value-at-Risk (VaR) as a measure of effectiveness (MOE) to assess the risk share for the public and private entity in a PPP project. Bootstrap simulation is used to generate the risk profile savings in vehicle operating cost, and in travel time resulting from demand-responsive traffic. The VaR for Internal Rate of Return (IRR) is determined for public and private entity. The methodology is applied to a case study involving such a joint venture in India, the Mumbai Pune Expressway/National Highway 4 (MPEW/NH4), and fiscal implications from the perspective of the public and the private entities are examined. A comparison between deterministic and risk based economic analysis for MPEW/NH4 is presented. Risk analysis provides insightful results on the economic and financial implications from each participant's viewpoint.  相似文献   

14.
The starting point of this paper is that the collection costs of urban road pricing have turned out to be unexpectedly high. A comparative cost analysis of the congestion charging system of London, Stockholm, Oslo and Singapore also shows that there are large collection cost differences. The most striking difference is between Oslo and London. Oslo, like Stockholm has the necessary, natural, qualities for a central city toll ring with a limited number of entrances; just 18 and 19 tollgates are required. For large historic cities like London with hundreds of inlets to the central city, tollgates at every entrance would involve high investment costs and be very obtrusive in the street scene. The problem is, however, that the present London charging system, with no tollgates, shows high running costs, ten times higher than in Oslo, in spite of the fact that the charged number of vehicles is the same in the two cities. This is a formidable obstacle to alleviating urban traffic congestion in many big cities.The charging technology could hopefully be developed, however, another approach is to develop and combine other measures including traffic regulation, parking policy and public transport subsidisation, which would be only second-best in a hypothetical situation where road pricing is without costs. This paper focuses on parking policy. Two strands of parking policy reform are discussed; fringe benefit taxation of free workplace parking which has recently been introduced in Sweden and a two-part tariff at parking meters, which is suggested as an extension of congestion charging to all day traffic within the central city.  相似文献   

15.
This paper presents a methodological disaggregated approach to analyze the impact of interventions on road safety. The model aims to describe the accident rates of an individual using mileage as a measure of risk exposure. The model is formulated as a system of equations that takes into account interactions between the mileage of a given individual and the other drivers. Once estimated, the model acts as a simulator allowing us to measure the performance of policy interventions to increase road safety.  相似文献   

16.
我国现行的道路养护主要采取矫正性养护方式,往往错过了最佳养护时机,导致养护工程量大,费用高,周期长,对交通影响大,社会反响强烈。根据效果费用比最大原则确定预防性养护时机,阐述了基于生命周期费用分析的预防性养护费用的组成与计算方法,对预防性养护效果进行定量分析,根据效果费用比的计算结果确定公路沥青路面预防性养护的最佳时机。  相似文献   

17.
During the last 20 years, the reefer shipping sector has been characterised by a gradual changing process, leading from specialised vessels to reefer containers. In fact, the reefer bulk fleet has experienced an irreversible decline, while the reefer container fleet has shown a continuous growth. This article investigates the current major factors shaping the reefer shipping industry, in order to understand the economic drivers inducing competition between bulk and containers. Therefore, a twofold analysis has been performed. First, an overview of the reefer market, including the cold chain, the demand for refrigerated products and the supply of reefer capacity given both by containership fleet and by conventional reefer fleet. Second, a specific case of the banana trade has been carried out for evaluating the revenues of each player involved in the banana cold chain followed by a cost analysis. The results reveal the market tendencies, focusing on the main sources of competition for bulk versus container.  相似文献   

18.
This paper presents the results of applying DRAG methodology to the identification of the main factors of influence on the number of injury and fatal accidents occurring on Spain’s interurban network. Nineteen independent variables have been included in the model grouped together under ten categories: exposure, infrastructure, weather, drivers, economic variables, vehicle stock, surveillance, speed and legislative measures. Highly interesting conclusions can be reached from the results on the basis of the different effects of a single variable on each of the accident types according to severity. The greatest influence revealed by the results is exposure, which together with inexperienced drivers, speed and an ageing vehicle stock, have a negative effect, while the increased surveillance on roads, the improvement in the technological features of vehicles and the proportion of high capacity networks have a positive effect, since the results obtained show a significant drop in accidents.  相似文献   

19.
滩海路是为了开发丰富的滩海石油资源而修筑的联系陆地与人工岛的纽带.浅海滩涂地带受潮汐影响,水陆界伸缩很大,这就造成了滩海路建设具有费用高、风险大、工期长、维修费用高的特点.堤高是影响滩海路堤工程建设总费用的关键因素,其合理确定对于保证滩海路通行天数、降低工程建设总费用是至关重要的.基于遗传算法,结合全寿命周期成本理论,建立了滩海路堤堤高多目标优化设计模型,并对渤海海域某工程地的滩海路堤进行优化设计,同原设计比较表明:利用该方法具有优越性,可以节省工程建设资金.  相似文献   

20.
结合塑料排水板加固软土路堤的工程实例,对比分析了排水板间距、堆载预压时间及堆载预压荷载对软土固结度、残余沉降的影响。总结出在工期允许的情况下,适当增加排水板间距并延长堆载时间,可有效减少工程造价并达到与较小排水板间距时相近的处理效果。在工期紧张的情况下,可通过减小排水板间距并结合超载预压,加快施工期沉降速率,满足残余沉降要求。  相似文献   

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