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1.
近年来,重庆市逐步建成了沿江化工产业带,内河航道运输成为重庆市危化品运输的重要方式之一。为提升重庆市内河航运危化品安全,本文分析了重庆市内河航运危化品的种类,阐述了重庆市内河航运危化品典型事故案例,指出了重庆市内河航运危化品运输存在的问题,研究了相应的处置技术,从政府和企业角度提出了重庆市内河航运危化品应急处置的对策与建议。  相似文献   

2.
公路施工关系到我国交通运输业的发展,而公路中关键部位的施工技术更是关系到我国的公路交通安全,所以一定要保证关键部位施工的安全性和稳定性,促进我国公路施工质量。针对我国公路关键部位的施工,文章提出了关键部位施工所遇到的问题,对关键部位的施工技术进行分析和探讨,希望可以有效的提高我国公路施工质量,促进我国交通运输业的发展。  相似文献   

3.
This paper analyzes some of the changes that took place in the structure of energy use for passenger travel in industrialized countries. Data is presented on energy use and travel activity for the four major modes of travel — automobile, bus, rail and air — for eight OECD countries: the United States, Japan, the United Kingdom, West Germany, France, Italy, Sweden, and Norway. We use the Laspeyres and Divisia indices to analyze the causes of the change in energy use between 1970 and 1987. The total change in energy use for travel is explained by changes in domestic passenger transport volumes, the mix of modes of travel, and the energy intensities of each mode. We have found two important effects that have a fundamental impact on energy use for travel since 1970. First, shifts among modes of transport towards more energy-intensive ones and large increases in volumes of travel (measured in passenger-kilometers) increased energy use for travel in many OECD countries, often more rapidly than the overall growth in GDP. Second, energy intensities, measured in mJ/passenger-kilometer, of passenger transport fell only in a few countries between 1970 and 1987. Even though individual automobiles have become more energy-efficient, greater size, power, and weight, worsening traffic conditions in Japan and Europe, and fewer people in cars restrained or even offset efficiency improvements. Particularly notable are the increases in intensities in Japan and Germany. The most important exception to this trend was the United States, but the intensities of land-based travel remain higher there than in most other countries. These findings lead to a pessimistic outlook for future energy use for travel. After all, if little or no energy was saved during the decades of high fuel prices, what can be expected in the 1990s?  相似文献   

4.
Changes in the commuting structure of the Toronto CMA are examined using 1971 and 1981 census journey to work data. There have been important changes in household structure, the employment base and the associated location decisions which in turn have created significant changes in commuting structure. The proportions of one‐ and two‐person households increased sharply over the decade and many of these smaller‐sized, high occupational status households were located in the older inner residential areas. The bulk of the larger‐sized households continued to be located on the developing fringe where housing prices are much lower. The structure of the employment base shifted over the decade with a reduction in the proportion of manufacturing jobs and growths in the proportions of jobs in finance and services, with the bulk of these office‐based jobs located in the Yonge Street transit corridor. Job growth in the suburbs was dominated by employment in manufacturing, transportation, trade and services. The addition of some 100000 jobs in the Yonge Street corridor resulted in strong commuting growth from the inner suburbs as well as from the newly developing outer suburbs. About half of the labour force living in the outer suburbs in the decade found local jobs, with the remainder of the labour force commuting to jobs in Metropolitan Toronto, principally along the high‐mobility transit and freeway corridors.  相似文献   

5.
Nash  C.A. 《Transportation》1974,3(3):225-242
There are two ways in which new road schemes may influence capital expenditure on vehicles. Firstly, by improving utilisation of existing vehicles, the size of fleet needed to perform a given volume of work may be reduced. This will clearly reduce the amount of capital tied up in motor vehicles at any point in time, and to the extent that vehicle life is determined by age rather than mileage run, will also yield savings in terms of investment in new vehicles. Secondly, by generating additional road traffic, road schemes may lead to an increase in the stock of vehicles in use.This paper argues that the current treatment of vehicle depreciation and interest charges in U.K. cost data fails to allow correctly for either of these items. Errors of logic occur in the way in which the capital stock of vehicles is valued, and in the fact that certain overheads are ignored even when fleet size changes. Moreover, the empirical evidence supporting the current partitioning of depreciation into overhead and running cost components, and the assumption of constant hours in service after an increase in journey speed seems of doubtful validity.An alternative method of calculating vehicle capital costs, based on the concept of annual capital charge, and making explicit the assumptions with respect to vehicle utilisation, is advocated, and the sensitivity of results to the view taken of the latter is demonstrated by means of specimen calculations.  相似文献   

6.
利用3D-σ有限元程序对近距离平行隧道的三种典型开挖方式进行了三维数值模拟;分析了在三种不同开挖方式下地面沉降槽形状及发展、土体和隧道的位移特征、岩体横向位移、衬砌内部应力;同时对相向同步开挖的各施工步进行了位移分析。数值分析结果表明,近距离平行隧道采用相向同步开挖对岩层扰动相对较小、地表及隧道位移量较低、衬砌时的应力较小。相向同步开挖与同向开挖时地表沉降槽的形状明显不同。  相似文献   

7.
Michael Roe 《运输评论》2013,33(3):229-243

This review emerged from an opportunity provided in 1988 to the author to study the process of Hungarian transport planning in general, and that of the major regional city of Pécs in particular.

It begins by outlining the difficulties of obtaining detailed information on transport policy‐making and planning in Eastern Europe, and then goes on to analyse the situation in Hungary as a whole since the early 1960s. The specific situation in Pécs is then discussed in relation to national transport planning, with detailed case studies drawn from problems on the local and regional road network, the growth in car ownership and usage, the development of local and inter‐regional rail services, the provision of adequate local bus services, and the growth of local taxi services.

The problems stemming from State intervention and planning control in local transport are emphasized, as are the increasingly difficult issues of the Hungarian economy in constraining public investment. The paper concludes with a discussion of the relationship of the problems of Pécs with those of urban areas elsewhere in Europe, and emphasizes the particular difficulties faced by East European planners in the future.  相似文献   

8.
文章结合目前广西交通规费征稽工作现状,分析了2006年征稽工作的新形势,提出今年规费征收工作应重点在“保费源、查漏征、治外挂”三个方面下功夫,堵住各种偷、逃、漏规费的渠道,力争2006年广西交通规费征收实现新突破。  相似文献   

9.
随着城市化的发展,珠三角城市交通能源消耗和碳排放迅速增长。为了探讨珠三角城市低碳交通的发展方向,本文采用LEAP模型,以珠三角的佛山市为例,模拟了不同情景下交通总量、陆运和水运的能源消耗、能源结构和碳排放由2011至2030年的变化情况;并据此提出了珠三角城市低碳交通发展对策。结果表明:水运在交通运输中所占份额逐渐被陆运替代,将形成陆运为主、水运为辅的交通模式;在交通总量、陆运和水运等的交通能耗及碳排放方面,低碳情景均小于基准情景,且呈水运小于陆运的态势;而清洁能源使用比重的增加则有利于交通领域的低碳发展。珠三角城市低碳交通发展需关注陆运交通,提高清洁能源在陆运中的使用比重,优化陆运与水运的交通布局,提高运输及能源利用效率。  相似文献   

10.
This paper reviews a number of recent innovations in the regulation and operation of taxicabs in U. S. cities. The paper discusses the growing involvement of various levels of government in public transportation programs which affect the taxicab industry, and identifies the opportunities and problems created for the industry by this increased government activity. Innovations in the types of public transportation services which can be provided by taxicabs are discussed first, followed by a review of the administrative procedures which can be employed to involve taxicab companies in publicly funded programs. Proposals for changes in the regulations governing taxicab services and prices are discussed next, with particular attention to significant regulatory changes which have been implemented in U.S. cities in recent years. Finally, innovations in the technology of taxicab operations are reviewed, including improvements to vehicles, computerized dispatching techniques, and procedures and equipment for computing fares for taxicab services.  相似文献   

11.
现场清管作业时,清管器经常被卡堵,严重时会影响生产.因此,为降低热油管道清管过程中的卡堵风险,根据清管器在含蜡热油管道中的受力情况和运行规律,结合输油管道的现场运行管理经验,分析含蜡热油管道清管过程可能遇到的卡堵,对此提出可靠的应对措施,以杜绝含蜡热油管道周期性清管中各种事故的发生,保证热油管道清管工作的安全进行,为今...  相似文献   

12.
Congestion pricing was introduced in Stockholm in 2006, first as a trial followed by a referendum, and permanently from 2007. Public attitudes to the charges became more negative during the period from the decision to the start of the system. Once the trial started, public attitudes became dramatically more positive over the following years, going from 2/3 against the charges to more than 2/3 in favor of the charges. Self-reported changes in behavior and attitudes considerably underestimate actual changes: about 3/4 of the decrease in car trips and more than half of the change in attitudes seem to have gone unnoticed by respondents, ex post. Self-interest and belief in the charges’ effectiveness strongly affect attitudes at any given point in time, but can only explain a minor part of the change in attitudes. I suggest that the debate and the shift in attitudes can be understood as a public and political reframing of the congestion charges over time.  相似文献   

13.
This paper investigates the perceptions of key participants in the Dutch Cost–Benefit Analysis (CBA) practice regarding substantive problems when appraising spatial-infrastructure projects with CBA. Two research methods were applied. Firstly, 86 key participants in the Dutch CBA practice were interviewed in-depth in order to obtain an overview and a ranking of perceived substantive problems with CBA in the Netherlands. Secondly, the people interviewed were also asked to fill in a written questionnaire in which they were asked to rank the substantive problems once again, in order to improve the validity of the ranking; 74 of the participants completed this questionnaire. The most important conclusions of this paper are, firstly, that key participants in the Dutch CBA practice consider ‘problems with the estimation of the non-monetized project effects’ as the most important substantive problem cluster and ‘problems with monetizing project effects’ as the second most important substantive problem cluster. Secondly, key participants in the Dutch CBA practice consider the ‘problem analysis’ in a CBA to be a very important substantive problem. Thirdly, there is, in a broad sense, consensus among the different groups in the Dutch CBA practice concerning their perception of the seriousness of problem clusters and the way they rank the problem clusters. Fourthly, a large part of the substantive problems mentioned by the key participants in the Dutch CBA practice are non-specific CBA problems.  相似文献   

14.
Electrification of the transport sector is considered as a solution to reduce greenhouse gases (GHGs) emissions and achieve sustainable mobility. Specifically in the case of electrification of passenger vehicles, various industrial and policy initiatives have been introduced. In this article, we present and assess three approaches – pro-technology, pro-simplicity and mix (of the aforementioned approaches) – to achieve target emission reductions in the Norwegian road transport sector. We also assess the influence of including ‘Guarantee of Origin’ certification for the electricity production in accounting for typical consumption electricity mix in Norway.Results show that for the same reductions in tail-pipe GHG emissions, pro-technology, pro-simplicity, and the mix scenario offer 22%, 29% and 28% reduction in the life cycle GHG emissions respectively, compared to the reference scenario in year 2020. However, the pro-simplicity scenario requires 25% reduction in vehicle-km driven compared to the pro-technology scenario, which provides the same passenger car mobility as in the reference case. When the GHG intensity of the electricity mix used to power EVs is corrected to account for actual consumption mix in Norway, a 13% reduction in the net GHG benefit of pro-technology scenario is observed.  相似文献   

15.
The effects of highway development on housing prices   总被引:1,自引:0,他引:1  
The purpose of this research is to estimate the effects of highway development projects on the price of housing. Transportation development projects, highways in particular, improve a certain area’s accessibility but also increase its levels of exposure to traffic intensity and noise pollution. These externalities are evaluated by homeowners and residents and are reflected in the price of housing. In this paper, we use several repeat sales model specifications, including difference-in-differences estimators, and control for neighborhood effects to examine housing price trends in the municipalities around two newly developed highways in the Netherlands. The results of the research demonstrate that changes in accessibility result in a significant positive effect on the price of housing in nearby municipalities, but that increased noise pollution and traffic intensity levels result in a decrease in prices. The findings also confirm that combining the total effects of all externalities, the effect of highway development on the price of housing is generally positive, and this effect is salient even before the project is completed due to public anticipation effects.  相似文献   

16.
The number of policy initiatives to promote the use of bike-and-ride, or the combined use of bicycle and public transport for one trip, has grown considerably over the past decade as part of the search for more sustainable transport solutions. This paper discusses the experiences with, and impacts of, such initiatives in the Netherlands. The Dutch measures to promote bicycle use in access trips have been generally successful. A country-wide program to upgrade regular and secure bicycle parking at train stations has led to an increase in user satisfaction and a growth in bicycles parked at stations. Smaller programs to stimulate the combined use of bike-and-bus have resulted in an increase in bicycle use, bus use, and share of infrequent bus passengers. Bicycle lockers at bus stops are hardly used by bus passengers, due in part to the dominance of students among bus users as well as the relatively high price of lockers in comparison to the value of bicycles used for access trips. Measures to promote the use of the bicycle in egress trips have met with more varying results. Projects to introduce leasing bicycles for egress trips have failed to attract passengers, for both train and bus services. In contrast, the introduction of flexible rental bicycles at train stations has resulted in a small reduction in car use, growth in train trips, and growth in bicycle use for non-recurrent trips. The Dutch experiences suggest some lessons for promoting bike-and-ride in countries and cities with a less well-developed bicycle infrastructure.  相似文献   

17.
The Second International Conference on New Survey Methods in Transport was held at Hungerford Hill, Australia in September 1983. The aims of the conference were to provide a focus for discussion of survey methodology and to establish bench‐marks with respect to the state of the art in various facets of transport surveys. The conference evolved around workshops in twelve key areas: sample design, survey needs for modelling, questionnaire design and piloting, perceptual studies, diary surveys, longitudinal studies, interactive survey methods, freight surveys, traffic surveys, total design concepts, response errors and data correction, and coding and computing.

A number of plenary keynote papers were also presented describing the state of the art in cross‐sectional, longitudinal and interactive survey methods. Emerging from the conference discussions, six key issues were prominent; the gap between the state of the art, as espoused by researchers, and the state of practice, as employed by practioners; the differences in results obtained when employing different survey methods to collect essentially the same data; the emerging use of the telephone for the conduct of interview travel surveys; the interaction between survey methods and demand modelling and the disparate levels of sophistication in the two areas; the role of microcomputers in the design, conduct and analysis of transport surveys; and the need for practitioners to engage in controlled experimentation, so that methodological advances may continue to be made in the field of transport surveys.  相似文献   

18.

Today, the extended transport infrastructure along with the communications and information technologies are to a large extent the generator of integration processes all over Europe. Novelties in this area have brought about important changes in the production conditions, distribution and consumption, which exert influence on the changing of economic structure, including similar changes in social, cultural and political relations. In the future, the social and economic development of Slovenia will depend on proportionate development of regions and on the embodiment of Slovenia in a wider European space. The transport infrastructure of Slovenia, along with its transport system, should be integrated in the European transport system in such a way that the developmental interest of Slovenia is fully highlighted and included to an optimum extent in the course of Slovenia's integration to the EU.  相似文献   

19.
With more than 3,200 km of track, the Spanish high-speed rail network is the longest network in Europe and the second largest in the world after China. Due to its geographical location in southern Europe, the entire network is exposed to periods of elevated temperatures that can cause disturbances and severe disruptions such as rail deformation, or in the worst case, lateral track buckling. In this study, the vulnerability of the current Spanish high-speed rail network is analysed in terms of track buckling failures with a Monte Carlo simulation. Downscaled temperature projections from a range of Global Climate Models (GCMs), under three Representative Concentration Pathways (RCP4.5, RCP6.0 and RCP8.5), were forced in a buckling model and particularized for different segments of the network. With that, the proposed methodology provides the number of rail buckles expected per year by assuming current maintenance standards and procedures. The result reveals significant increase in the occurrence of buckling events for future years, mainly in the central and southern areas of mainland Spain. However, relevant variations are found in different climates and time horizon scenarios in Spain. The anticipated buckling occurrences highlight the vulnerability of the Spanish rail network in the context of global warming scenarios. Overall, the proposed methodology is designed to be applicable in large-scale railway networks to identify potential buckling sites for the purpose of understanding and predicting their behaviour.  相似文献   

20.
钱寒峰 《综合运输》2021,(3):139-142
优先发展公共交通,倡导绿色出行方式,可以缓解交通拥堵,减少交通污染。河北省衡水市在国内率先实施了冬季公交免费乘坐政策,政策出台的初衷是为了改善衡水市空气质量,经综合评估后,该政策在提高公交乘客满意度、增强公共交通吸引力和缓解交通拥堵等方面取得了明显成效,为国内三、四线城市的公共交通优先发展提供了有益的经验借鉴。  相似文献   

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