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161.
While some countries have made progress in encouraging more sustainable transport and travel patterns, there are limits as to how far this can be taken simply by looking at the decarbonisation of transport systems, since most travel is a derived demand and hence is strongly influenced by decisions taken by public and private sector agencies in different sectors. The paper first identifies some of the major non-transport sector influences on different aspects of travel behaviour. It then looks in more detail at changing patterns of grocery shopping over the last half century, and how these changes have been associated with new non-transport technologies and accompanying developments in business and social practices. Next, a simple visual spreadsheet tool is presented, that has been used by agencies to explore the main cross sector impacts (both positive and negative) of their major location and operating decisions. Finally, the paper proposes three ways in which cross sector synergies can be encouraged: (i) by giving each sector or major organisation responsibility for all CO2 emissions associated with its activities, including those generated by the travel of its staff, customers, suppliers, etc.; (ii) by making major policy making within government a cross sector activity; and (iii) by developing a common, cross sector appraisal methodology for assessing the full range of impacts of policy proposals. 相似文献
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沥青路面因降水或冬季雨雪结冰变得湿滑,会严重威胁车辆行驶的动力性及安全性。研究提高路面冬季防冻及抗滑性能的关键技术势在必行。采用以SMA沥青混合料作路面磨耗层、发热管加热系统融雪化冰、温控介质调控温度的研究思路和技术途径,有望制备出能够自动加热融雪除冰,防冻抗滑功能兼备的沥青路面。 相似文献
165.
新媒体传播技术发展趋势研究 总被引:1,自引:0,他引:1
蒋宏 《上海交通大学学报(哲学社会科学版)》2008,16(6)
本文针对新媒体技术的应用趋势及其已经或者可能对社会产生的影响,分别从新媒体技术的突破和发展对媒体乃至社会环境的影响和作用、对信息传播精准效果的行为认知测定、对人际间的信息交流与家庭生活空间、气氛的智能调节的交互性、对新媒体搜索技术和自身潜能挖掘等方面进行了分析与探索,加深了对新媒体技术应用与社会活动关系的分析与研究,提出了新媒体如何走向“人性化”的问题方向。 相似文献
166.
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
167.
The application of social marginal cost pricing (SMCP) in PPP's in the railway sector faces several challenges. We examine in detail the practical applicability of SMCP in railway PPPs from the perspectives of cost accounting and effectiveness of SMCP towards the allocative efficiency goal, addressing the likely drawbacks in conciliating the welfare objectives of SMCP with the objectives of project financing (cost recovery) and value for money that justify the realization of PPP's. To this end, we combine theoretical analysis with the observation of empirical results of a case study. We split the analysis per type of private service provision, which can be for service operation or infrastructure management. For infrastructure management, we recommend splitting the operator remuneration and the track access charges. For service operation, we argue that the correct decision on source of funding of the service operator should depend on the characteristics of the contract. 相似文献
168.
IntroductionWDM passive optical network (PON) is an at-tractive solution for future broadband access net-work in that it offers the potential of large capaci-ty, network security and data transparency[1]WDM PON connects the optical line terminal( OLT ) with multiple optical network units(ONU) through a splitter. The OLT has an arrayof m fixed-tuned transceivers, each tuned to a dif-ferent wavelength. Each ONU is equipped withone fixed transmitter (control channel) and onetunable trans… 相似文献
169.
在自媒体时代,加强大学生网络舆情现状调查研究,有助于增强高校在网络舆情视域下思想政治教育工作的实效性.以W学院为例,探讨大学生网络舆情新的时代特点,探析网络舆情引导工作存在的问题,提出大学生网络舆情引导的策略. 相似文献
170.
Lu Honglun 《西南交通大学学报(英文版)》1999,7(1)
With a porous medium regarded as an immiscible mixture of multiphase and each phase as a miscible mixture of multi-constituent, a systematical research on the kinematics and field equations for porous media is carried out from the point of view of mixture theory. It is shown that the motion of each phase is the mathematical average of the motions of all constituents in the phase, and that the motion of porous media may be described as the motion of the skeleton and the relative motion of each phase with respect to the skeleton. The influence of mass exchange between different constituents in each phase and the influence of mass exchange of same constituent between different phases in porous media are considered in field equations which are self-consistent in theory. All the field equations in the references are special cases of the equations proposed in this paper. 相似文献