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991.
Without questioning the fact that to achieve efficiency emitters should pay for the true costs of their actions (a core principle of economic policies such as pollution taxes), we find sufficient evidence in the literature to demonstrate that many other policy instruments can be used in combination with taxes and permits to ensure that the transport needs of the present generation can be met without compromising the ability of future generations to meet any needs of their own.The policies and policy aspects considered in this paper broadly fall into three categories: physical policies, soft policies, and knowledge policies. All three aim to bring about changes in consumers’ and firms’ behaviour, but in different ways. The first category includes policies with a physical infrastructure element: public transport, land use, walking and cycling, road construction, and freight transport. We also consider the particular challenges for mobility in developing countries, and how these may be addressed. Soft policies, on the other hand, are non-tangible aiming to bring about behavioural change by informing actors about the consequences of their transport choices, and potentially persuading them to change their behaviour. These measures include car sharing and car pooling, teleworking and teleshopping, eco-driving, as well as general information and advertising campaigns. Finally, knowledge policies emphasise the important role of investment in research and development for a sustainable model of mobility for the future.The main findings can be summarised as follows.

Physical policies

An increase in the use of public transport, combined with a decrease in the use of private cars, can reduce traffic congestion and, more importantly, carbon dioxide (CO2) emissions, as public transport generally causes lower CO2 emissions per passenger kilometre than private cars. Public transport fares are subsidised in most places, which can be justified by economies of scale and by the fact that public transport can reduce total road transport externalities. London, Singapore, Portland and Curitiba are all examples of good practice at government level, having achieved reliable, frequent and integrated public transport.Policies to increase public transport use must be part of an integrated policy. Integrated policy refers to integration across different modes of transport, different government objectives (such as the economy, health and the environment), considering the needs of different social groups, and coordinating action between the relevant government institutions. There is evidence that a lack of coordination can jeopardise the achievement of policy objectives.A sustainable model for transport policy also requires integration with land-use policies. These may be somewhat limited within the bounds of existing cities, but as cities grow and new cities are built, urban planners must put more emphasis on land use for sustainable transport in order to reduce congestion and CO2 emissions. Sustainable land-use policy can direct urban development towards a form that allows public transport as well as walking and cycling to be at the core of urban mobility.Walking and cycling, which improve general health and produce no tailpipe emissions, constitute an excellent alternative to motorised transport on short-distance trips within towns and cities. The policies which can incentivise walking and cycling include crime reduction to make streets safer, well-maintained and clean pavements, attractive street furniture, safe crossings with shorter waiting times, dedicated cycle paths, showers in offices, and lower speed limits, to name but a few.Road construction and expansion used to be seen as one of the most promising ways to reduce traffic congestion. However, in the mid-1990s, the issue was reassessed and it was found that building and expanding roads, increased, rather than decreased, congestion, and ultimately induced higher levels of travel demand. The reason for this is that the extra capacity reduces the general cost of travelling and the less expensive the travel, the more it will be demanded. Regarding freight modal shift, road transport is much more polluting than rail per tonne-km of goods transported and therefore a shift towards greater use of rail in freight transport is desirable. Inadequate infrastructure is the main obstacle preventing this modal shift taking place.Developing countries face great mobility challenges: rural areas are often extremely poorly connected to transport infrastructure, such that, in contrast to the situation in developed countries, the benefits of road construction can strongly outweigh the total costs (including environmental ones). The main challenge, however, is to develop a solution to the problems arising from the combination of urbanisation and motorisation. Integration of transport and land-use policy will be key to rising to this challenge.

Soft policies

Car sharing and car clubs can also potentially reduce CO2 emissions, although the aggregate reduction in congestion and emissions has not been measured with an adequate degree of precision in the literature. Teleworking and teleshopping can potentially reduce congestion and also CO2 emissions. However, the evidence for this reduction is rather mixed, as it is unclear whether these measures lead to overall reductions in road transport.Eco-driving campaigns aim to inform and educate drivers in order to induce them to drive in a fuel-efficient and thus environmentally friendly way. There seems to be some consensus in the literature that eco-driving could lead to reductions in CO2 emissions of around 10 per cent.Information and education policies have often been advocated as instruments which may affect behavioural change. We find in this paper that these types of measures are necessary, but not sufficient for behavioural change. Advertising and marketing may go a long way in changing peoples’ behaviour. In California, for example, Kahn (2007) finds the “Prius” effect: the Toyota Prius is preferred by consumers relative to other similarly green vehicles, probably due to extensive marketing and celebrity endorsements. Family life changes are also found to trigger changes in behaviour ( [Goodwin, 1989] and [106]). People whose lives are being changed by some important development (birth of a child, retirement, etc) tend to respond more to changes in the relative attractiveness of different transport modes. Advertising campaigns promoting a modal shift towards public transport, for instance, may thus be more successful if targeted at people in the process of important life transitions.

Knowledge policies

Research and Development is crucial for developing sustainable and low-carbon transport for the future, and it is essential that governments provide incentives to undertake R&D, so that new low-carbon technologies in the transport sector can be demonstrated and applied at a large scale.Finally, we consider the issue of policy combination and integration. There is evidence that the combination and integration of policies can lead to positive side-effects and synergies. Policy integration is crucial in order to rise to the challenges we face in moving towards a sustainable mobility model. We conclude that classical economic policies may be successfully combined with a number of policy measures discussed in this paper in order to achieve sustainability in transport.  相似文献   
992.
Developing countries and countries in transition represent between 85% and 90% of the world’s population and face unique public transport challenges that are not necessarily present in developed countries. Issues such as the affordability and accessibility of public transport, funding support and capacity to implement are some of the challenges these countries face. Barriers to strategy implementation in these countries could be a failure to understand the broader business and social environment, poor leadership, a lack of inter-disciplinary and inter-implementer collaboration, and weak monitoring and feedback loops. Weak institutional frameworks are evidenced in inappropriate structures often resulting in institutional inertia and conflict. Over-promising of potential impacts and benefits together with a failure to develop sustainable funding mechanisms often lead to a lack of implementation. The workshop argued that different competition and ownership solutions are needed for a range of factors. This poses a challenge to the THREDBO community as it could mean that the traditional concepts are either not relevant or not usable in the majority of the world’s developing countries, or that the traditional approaches are relevant in many respects but need to be substantially extended and adapted to be applicable and usable in the rest of the world.  相似文献   
993.
This paper presents a number of reasons that are responsible for the disappointment of authorities in their operators’ efforts to develop public transport (PT) to the advantage of their travellers. The lessons drawn in this paper are based upon the competitive tendering experience of the authors and upon the results of meetings organised with parties involved in competitive tendering and aimed at exchanging lessons. There appears to be three main causes: (1) there is freedom for the operator, but the contract is bad; (2) there is freedom for the operator, there is a good contract, but there is no market; and (3) there is freedom for the operator, but the operator is not able to use it. The paper concludes with a few perspectives for improvement.  相似文献   
994.
This study aimed to investigate and analyse the internal pre-purchase transport choice behaviour of Chinese and Australian tourists in Scotland. A literature review was carried out to explore the pre-purchase internal transport choice behaviour of tourists. A questionnaire was designed based on the findings of the literature review. A convenience sampling plan was developed to achieve a valid and statistically significant sample size for the two selected markets: Chinese and Australian tourists. Surveys were distributed directly within the Highlands and indirectly through tour operators. A number of significant differences in pre-purchase transport choice behaviour were found between independent and tour travellers and between Chinese and Australian tourists. A number of other variables including English language capabilities, country of residence, education levels and previous travel experience were also found to have significant influences on the process. A number of recommendations relating to market analysis and research, promotion and product development were made to Scottish tourism transport providers based on the findings.  相似文献   
995.
瓯江河口挟沙力公式研究   总被引:1,自引:0,他引:1  
借鉴两种河口区常见的公式形式,考虑到挟沙力主要与水流流速u,水深h,泥沙沉降速度ω,以及重力加速度g有关.进而运用峰值法、半潮平均及全潮平均法处理瓯江口1999年以及2005年水文实测资料,并用不同方法对资料进行处理后,分别作出垂线平均含沙量S随v2/(gh)和v3/(ghw)的变化图,进行相关分析,得出在全潮平均时S与v2/(gh)的相关系数最好.最后用matlab进行回归分析,得到相关系数较好的瓯江河口挟沙力公式.  相似文献   
996.
介绍了"基于广州交通模型的交通影响评估方法"体系,阐述了应用广州交通模型把握研究项目宏观出行特征,并在此基础上建立了细部模型的技术步骤,提出了基于城市整体模型的交通影响评估方法。  相似文献   
997.
介绍了采用基于组合公钥(CPK)技术的认证原理,提出一种简化或取消第三方CA机构或证明,减少庞大的支持机构和维护量,从而达到简化IPSec协议的实现过程和提高认证效率。  相似文献   
998.
道路危险货物运输企业安全管理问题的探讨   总被引:1,自引:1,他引:0  
分析了道路危险货物运输企业的发展现状,指出道路危险货物运输企业安全管理存在的不足,提出了加强道路危险货物运输企业安全管理的措施。  相似文献   
999.
基于蚁群优化算法与出租车GPS数据的公众出行路径优化   总被引:1,自引:0,他引:1  
以出租车GPS采集的浮动车数据为依据,研究出租车驾驶员路径选择的认知及类蚂蚁的行为特征。根据城市道路功能等级与出租车的通行频率等信息素,建立出租车驾驶员路径选择信息素等级路网,并以此作为路网初始信息素,综合考虑路径通行时间、通行距离、路径信息素等级等多个因素,提出了基于蚁群优化算法的公众出行路径规划优化算法。以武汉市路网和浮动车为试验数据,将模型规划的道路与浮动车数据库中的轨迹进行了比较。结果表明:基于蚁群优化算法与出租车GPS数据的公众出行路径同出租车驾驶员选择的出行路径相似度很高,能为公众出行提供出租车驾驶员选择的行车路径。  相似文献   
1000.
城市轨道交通项目合同全过程管理   总被引:3,自引:1,他引:2  
轨道交通项目建设机构在建设过程中对整个项目的全过程的合同管理,大致可分为招标策划、资格预审、招标与定标、合同执行、合同总结与后评估、合同管理培训等六大阶段。介绍了每个阶段合同管理的重要性,并提炼出全过程管理中各阶段的关键控制点。  相似文献   
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