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801.
This chapter offers a theoretical examination of the following questions: what are the issues that arise when Social Marginal Cost Pricing is to be incorporated in Public-Private Partnerships (PPPs); and how may these issues be dealt with?We first briefly discuss Public-Private Partnerships in transport: what are the defining characteristics and what are the main types that exist in the different modes of transport? Next we consider the economics of Public-Private Partnerships, in particular from the viewpoint of incentives. Subsequently we identify and examine the issues that arise when Social Marginal Cost Pricing is to be incorporated in PPPs as a regulation with regard to pricing in the transport sector. Lastly, we investigate the possibilities of resolving these issues.  相似文献   
802.
Kulsreshtha  Mudit  Nag  Barnali 《Transportation》2000,27(2):221-241
In this paper we derive long run structural relationships for all the three classes, viz. upper, second and ordinary second class, of non-suburban long distance passenger transport demand for Indian railways using annual time series data for 1970–1995. We employ some of the recent developments in multivariate dynamic econometric time series modeling including estimation of long-run structural cointegrating relationships, short-run dynamics and measurement of the effects of shocks and their persistence on evolution of the dynamic passenger transport demand system. The models are estimated using a cointegrating vector autoregressive (VAR) modeling framework, which allows for endogeneity of regressors. The demand systems are found to be stable for all the classes in the long run and they converge to equilibrium in a period of around 2–4 years after a typical system-wide shock. Any disequilibrium in the short-run is corrected in the long-run with adjustments in passenger transport demand and the price variable, i.e. real rate charged per passenger kilometer. Results show that travel demand in all classes would rise with income, although the rise is less than proportionate in the case of ordinary class. High price elasticity in long-run and short-run impulse responses indicate that passenger fare hike could lead to substantial decline in travel demand leading to decline in revenue earnings of the railways. This revised version was published online in June 2006 with corrections to the Cover Date.  相似文献   
803.
科学发展观是我国的一项重要的发展战略,而教育是我们社会大系统中的一分子,对于社会的建设和发展有着不可估量的作用,在国家发展、时代进步之际,我们必须以科学发展观为指导来审视教育、指导教育、统筹教育,使其全面、协调、可持续的发展。  相似文献   
804.
杨绍清 《中国铁路》2006,(12):10-15
陇海线西宝段作为西部路网惟一的200km/h提速改造工程,使西安铁路局站到了既有线提速改造的先进技术最前沿。西宝段在线路基础、电务设备、牵引供电设备、车辆等方面还不能适应开行200km/h动车组的需要。在提速改造工程中,西安铁路局注重引进消化吸收,从线路基础、电务系统、牵引供电系统以及动车组检测设备等方面采用了大量的先进技术,为解决开行200km/h动车组条件下的运输组织、调度指挥、车流调整、接发列车、旅客乘降组织,制定了陇海线西宝段提速改造工程的重点推进计划,确保提速改造工程的顺利实施。  相似文献   
805.
刘拥成 《中国铁路》2006,(12):25-28
在加拿大和美国,铁路客货运输公司全部市场化运作,铁路客运分别主要由VIA公司和AMTRAK公司承担。政府为了维护铁路公益性运输,对长期严重亏损的铁路客运业务进行补贴。借鉴两国经验,解决我国铁路的公益性问题,必须从国情出发,将市场和政策相结合。立法先行,明确我国铁路公益性运输的界限,补贴主体和补贴对象,并制定分类投资政策,实行分层决策制度。  相似文献   
806.
The economic and political reunification of Germany in 1990 unleashed a transportation revolution in Eastern Germany. After forty years of public transport dominance under socialism, auto ownership and use skyrocketed with the transition to capitalism. In only three years, ridership on public transport fell by almost 50%, and auto registrations per 1,000 population rose by almost 60%. The main reason for the sudden shift in modal split is the large increase in real per-capita incomes of Eastern Germans. Their purchasing power rose dramatically thanks to massive financial aid from Western Germany and access to hard currency for the first time. In addition, the relative cost of auto use has fallen sharply since reunification because public transport fares rose ten-fold, while gasoline prices and auto prices fell. The massive shift from public transport to the auto has caused severe problems of pollution, safety, equity, and congestion in Eastern German cities, partly because of the suddenness of the modal shift. Urban transport policy in Eastern Germany should adopt some of the strategies used for years in Western Germany to tame the automobile, while at the same time allowing high levels of auto ownership. Such strategies include auto-free zones, traffic calming, extensive bicycle pathways, vehicle emission standards, and parking restrictions. Finally, large investments will have to be made in Eastern Germany's dilapidated roadway and public transport infrastructure.  相似文献   
807.
研究目的:根据青海省引大济湟调水总干渠引水隧洞工程采用双护盾TBM快速施工和长距离运输的特点,研究如何通过调度集中控制系统对隧洞内的有轨运输车辆实施远距离集中自动调度控制,从而保证隧洞内运输车辆安全、快速、连续、有效运转,提高运输效率。研究方法:在分析研究轨道施工运输特点和铁路信号闭塞设备的基础上,通过调度集中控制系统对隧洞内的有轨运输车辆实施远距离集中自动调度控制。确定了特长隧洞采用单线运输轨线,并根据进度目标所需的运输量及运输系统的能力,每隔一定里程设一固定会车站来完成运输作业。研究结果:总结了特长隧洞施工有轨运输车辆调度控制系统的设备组成、控制原理及车站联锁控制与道岔转换实现区间闭塞的技术;提出了列车进路控制和区间闭塞接发车控制两种控制模式,提出了采用光缆传输、计算机联锁、PLC控制的现场总线式分布控制系统的方案。研究结论:特长隧洞施工有轨运输车辆调度控制系统可极大地提高单线运输轨线的运输能力和效率。  相似文献   
808.
本文研究了波浪对斜坡堤前沙质海底的冲刷作用,在部分立波的作用下,沙底呈现两种基本冲刷形态,其间又有一种过渡形态。可以通过本文定义的无量纲参数u′,确定冲刷形态。冲刷位置、深度、长度可按文中公式估算。文中不规则波的试验结果可用等效规则波,如T_(1/3)、H_(1/3)来表达。  相似文献   
809.
The concept of mobility-as-a-service (MaaS) was conceived in Finland, and it is characteristically user-oriented. Interest in MaaS has quickly spread across Europe along with the rapid advances in information and communications technology and the internet of things in recent years, as the realization of MaaS is consistent with the policy directions of the EU member states promoting the use of public transport.This paper describes the MaaS concept in EU, the birth of the concept in Finland and its background, and EU-wide policy level initiatives and their characteristics.  相似文献   
810.
对江海直达船首部砰击引起的鞭击振动进行了仿真分析,采用瞬态动力学模态分析法,计算过程中考虑附连水的作用。分析参数有砰击压力峰值和连续砰击次数,对比分析仿真结果,得出不同压力峰值和连续砰击次数的影响规律。  相似文献   
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