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1.
Book reviews     
The European Community Transport Policy: Towards a Common Transport Policy. By Jurgen Erdmenger (Gower Publishing Co. 1984) [Pp. 155.] £14.50.

Transport Reform: Changing the Rules. By Stephen Plowden. P.S.I. No. 642 (London: Institute, 1985.) [Pp. 250.] £6.50. ISBN 0–85374–258–8.

The Atlas of British Railway History. By Michael Freeman and Derek Aldcroft (London: Croom Helm, 1985.) [Pp. 128.] £12.95.

Losing Track. By Kerry Hamilton and Stephen Potter (Routledge & Kegan Paul in association with Channel Four, 1985.) [Pp. viii + 152.] £7.95. Paperback.  相似文献   
2.
It is about 20 years since the rail reform process in Europe began with the separation of infrastructure from operations in Sweden. This paper reviews the entire process, examining the objectives of reform, the different models adopted, and the key elements of separation of infrastructure from operations, competition both through open access and franchising and regulation and infrastructure charging. It is concluded that separation of infrastructure from operations involves costs, but is the most effective way of achieving within mode competition. Where operations do not greatly overlap and open access passenger and freight are unimportant, leasing infrastructure to passenger franchisees may be effective, but the model of vertical integration as separate subsidiaries within a holding company structure makes it difficult to ensure a level playing field for new entrants and is only effective where the vertically integrated operator remains dominant.  相似文献   
3.
In Britain, capacity charges are levied on train operators to cover the costs imposed by increased reactionary delays – i.e. the delay that an already late train causes to a following train. These charges are based on the link between capacity utilisation and the level of reactionary delay. An established method for measuring capacity utilisation was adopted called The Capacity Utilisation Index (CUI). In this paper, we propose an alternative methodology based on the theory that the level of reactionary delay will be determined by the minimum gaps that exist between trains. We test this measure with a new data-set for the East Coast Main Line and show that it performs better than CUI. Finally, we comment on the implications of this finding for charging and for the construction of timetables.  相似文献   
4.
5.
Ed Kase 《现代隧道技术》2004,12(Z2):352-363
Unforeseen, variable subsurface ground conditions present the greatest challenge to the heavy construction and civil engineering industry in the design, construction, and maintenance of large projects. A detailed, accurate site investigation will reduce project risk, improve construction performance and safety, prolong the life of the tunnel or structure,and prevent waste in over - design. Presently, site characterization and geotechnical engineering are limited by the inability to adequately describe these subsurface ground conditions.NSA Geotechnical Services has successfully applied seismic tomography and holography ground imaging technologies on tunneling and heavy civil excavations worldwide. Seismic signal waveforms traveling through a complex medium consist of various arrivals from refractions, reflections, scattering, and dispersion. Tomography and holography are proven inversion technologies for estimating location and extent of material property variations causing changes in signal waveforms.ent attenuation rates and velocities. Seismic waves will travel faster through competent material and be generally less attenuated than through broken/fractured ground or voids.encounters an interface between ground zones possessing different seismic properties. Most geologic structures, anomalies,and changes in lithology provide detectable seismic reflections if they are within a reasonable distance of the seismic source.This paper will present various applications of these technologies, illustrating how seismic imaging can provide accurate information regarding ground conditions associated with tunneling projects. With this information, engineers can complete projects safely, within time and budget constraints.  相似文献   
6.
There has long been conflict over the degree to which railways should follow commercial or social investment criteria. This paper outlines the components of a comprehensive social cost‐benefit analysis of railway investment, and then describes the current approach in Britain. British Rail investment proposals are subject to a purely financial appraisal, although in the subsidized sectors of the railway this is subject to the proviso that a ‘broadly comparable’ level of service should be maintained. Local authorities and private operators are able to apply for a central government grant towards the cost of schemes they sponsor. But grant is only payable in respect of external benefits—that is, benefits other than to public transport users. Sponsors are also expected to seek contributions from private developers wherever possible. The difficulties to which this approach leads are discussed, and illustrated with two case studies of actual schemes. In one, it appears that failing to consider disbenefits to bus operators (and in turn to users of bus services) could lead to investments being undertaken which are not justified. In the other, a scheme which yields a high Net Present Value could not go ahead, in the form that we evaluated, because there is no way of recouping enough of the user benefits as revenue. Both are examples of the sort of distorting effect on decision‐making the current regime may have.  相似文献   
7.

One of the biggest unresolved problems regarding the completion of the free internal transport market within the European community is the problem of harmonization of taxation on the road haulage industry. As the highest tax country, Britain might be expected to have to reduce its level of taxes as part of any harmonization.

This paper considers the current methodology of the British Department of Transport regarding the allocation of the track and external costs of road transport, in the light of developments in methodology and experience elsewhere in Western Europe and North America. We find a number of reasons for believing that, far from overstating the marginal social cost of use of roads by the road haulage industry, the current British approach actually understates it. Thus any move towards harmonizing tax levels may reduce taxes in Britain at a time when they should be increasing.  相似文献   
8.
In our critique for the Buses White Paper, we argued that ‘competition for licences’ could achieve most of the benefits of competition without the major disadvantages of ‘competition on the road’. In response to the comments of Beesley and Glaister, we explain how comprehensive franchising of good and bad routes alike would encourage effective competition, whilst providing conditions for the transparent continuation of cross‐subsidy where that was the choice of the local authority in question. We correct their misrepresentation of our arguments on the desirability of cross‐subsidy and on the case for minibuses, and explain why we believe that such cost savings as are achieved will be mainly at the expense of staff or customer service. Finally, we restate the case for believing that a unified planned timetable will provide a better service for a given level of resources than will uncoordinated competitive services.  相似文献   
9.
C. A. Nash 《运输评论》2013,33(3):269-282
This paper compares the major role played by suburban rail (S‐Bahn) systems in West German cities with the much more limited role of rail in the British conurbations. Clearly, the difference owes much to the institutional and financial arrangements in the two countries. In West Germany, large amounts of earmarked funds have been available for rail investment, whilst the Federal government has been willing to shoulder much of the burden of operating subsidies. The Verkehrsverbund has emerged as a highly effective way of coordinating fares and services without direct ownership of any mode of transport. By contrast in Britain funds for rail investment have been much more limited. Progress with integration has been far slower, and is threatened by current government policies regarding both bus deregulation and the abolition of the Metropolitan county councils. Whilst rail is firmly established in German cities, its future in Britain looks bleak.  相似文献   
10.
在大型工程项目的设计、施工和维护阶段,复杂多变的地下岩土工程条件对大型建筑和土木工程产业带来的巨大挑战令人难以想象.具体而言,通过准确的现场勘察可以降低工程风险,改善施工作业,确保施工安全,延长隧道或建筑结构的使用寿命,防止超设计的浪费.显然,由于缺乏对地下岩土工程地质条件进行合理描述的手段,限制了工程现场地质条件的表征和岩土工程技术的发展.NSA大地工程有限公司成功地将地震层析成像及全息岩土成像技术应用于隧道工程和大型土木工程开挖领域.经复杂介质传播的记录地震信号是由折射、反射、散射、弥散等多类波形所组成,层析成像和全息成像是常用的利用信号波形变化来估计介质性质变化的位置和范围的反演技术.·岩石三维图像(Rock Vision3DTM)技术的基本原理是基于地震能量在不同种类介质中以不同的衰减率和速度传播.通常,与破碎或裂隙发育的岩土体或空洞条件相比,地震波在完整坚硬的介质中传播时,具有更高的传播速度和更低的衰减.·TRTTM技术的基本原理是利用了地震波在岩土体中传播过程中遇到具有不同震动特性的岩土区带间的界面时部分地震波能量将产生反射的特性.绝大多数地质结构异常及岩性变化,在地震信号可及的距离范围内,均可形成可探测的地震反射.文章介绍了上述技术的各种应用条件,分析了地震成像技术在隧道工程施工中所能提供的与隧道工程施工有关的岩土工程地质条件方面的准确信息.根据这些信息,工程建设者可以按期在预定计划内安全地完成工程施工.  相似文献   
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