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1.
Abstract

The purpose of this article is to seek to reconstruct the ownership transformation involving Poland's State Road Transport (PKS) companies passed through after 1990. Data collected from various sources (above all the Internet) were used to establish the degree of advancement of the transformation processes. Despite the passage of 18 years since the new economic reforms were launched, privatization processes are not well advanced. State ownership remains dominant, in the form of Treasury companies as well as state‐owned enterprises. Privatization processes have encompassed fewer than half of all firms, the most popular form taken (in about a quarter of all analysed cases) involving leasing by workers. This would seem of major interest, attesting as it does to the greater activity of some worker's teams, as well as the passive role of the state in privatization processes. A much smaller number of firms (26) have been purchased by external investors, the only important international concern among these being Veolia, which had taken control of 11 PKS companies as of mid‐2006. By and large, it is the firms carrying passengers or passenger and goods that are in a much better situation, as opposed to the companies that are commodity‐carriers only. The majority of the latter have collapsed, or have undergone the kind of privatization that involves simultaneous shutdown. Mixed passenger and goods carriers have had to reduce their level of activity in commodity transport.  相似文献   

2.
Abstract

This paper summarizes the state-of-the-art for assessing the value of a statistical life (VSL) as a component of the costs of road accidents. It focuses on the most popular approaches for assessing the VSL, with respect to its theoretical foundations, current state-of-research and empirical evidence. Our paper also provides a first (to our knowledge) compendium of results for the VSL based on Stated Choice (SC) methods. Among the analysed alternatives, the willingness-to-pay (WTP) appears to be the leading approach for assessing the VSL and the SC methods represent the current state-of-the-art for determining the WTP for non-market goods. We conclude that the SC approach overcomes some of the most important shortcomings of the alternative approaches and offers a significant flexibility that can be used to address its own limitations. We also identify a significant need for research, as a gap between the methods employed in research (SC methods) and the state-of-the-practice (other methods) has emerged.  相似文献   

3.
ABSTRACT

The understanding of the competitiveness of different ports under the background of China’s “Belt and Road Initiative” (BRI) is critical for drafting appropriate plans and taking suitable actions to select the best port in the logistics supply chains. A novel Multi-Attribute Decision Analysis (MADA) was proposed for the evaluation of port competitiveness. In the developed MADA method, the interval Analytic Hierarchy Process and the projection method was combined for the evaluation of port competitiveness. Three container ports in Asia including Shanghai, Hong Kong, and Singapore were studied under the background of China’s BRI. The results demonstrate that the port of Singapore is the most competitive at the initial stage of China’s BRI, followed by Hong Kong and Shanghai in the descending order. The results were validated by sum weighted method and Technique for Order Preference by Similarity to an Ideal Solution method, and sensitivity analysis was also carried out. The competitiveness of the three ports in the next ten years were also studied with the consideration of the influences of China’s BRI, and the results reveal that Shanghai port can even exceed Hong Kong port and Singapore port if it can effectively take the advantage s of China’s BRI.  相似文献   

4.
The Government of the Territory of Hong Kong is the first in the world to propose a system of charging motorists directly for the use of congested roads. Hong Kong has more registered motor vehicles per unit length of road than any other country and the road system is physically separate from China. Despite the scheme's technical proficiency and ability to earn revenue well in excess of operating costs, there is doubt about equity and efficiency. In the end, traffic conditions were not seen to be sufficiently bad so the scheme's introduction has been postponed.  相似文献   

5.
Abstract

This paper presents a review of time-series analysis of road safety trends, aggregated at a national level, which has been performed in the period 2000–12 and applied to European national data sets covering long time periods. It provides a guideline and set of best practices in the area of time-series modelling and identifies the latest methods and applications of national road safety trend analysis in Europe. The paper begins with the methodological framework adopted for aggregate time-series modelling that will be considered, and then discusses a number of relevant applications to long-period data aggregated at the national level, whether for countries alone, or for groups of countries. Some analyses, which were performed at the disaggregated level, are also provided, as they are being used more and more. Finally, the paper summarizes and discusses the significant changes in aggregate road safety trend analysis which occurred during the period and provides recommendations for continuing these research efforts.  相似文献   

6.
Road-pricing theory asserts that the optimal speed of a road network is that where vehicles pay the marginal social cost of their journey, rather than an average private cost if no price is imposed. This paper aims to show that this is misconceived. In big congested cities, the running speed of the road network is set by the direct journey speed achieved on the appropriate mass-transit network, both within and to the city centre. After dividing by the appropriate route factors to convert running speed to direct speed and allowing for access to convert kerb-to-kerb to door-to-door speed, the average direct journey speeds by car are identical to those on the mass-transit system for equivalent journeys when there is suppressed demand for car travel. Road pricing should thus be seen, not as a tool for increasing road speeds, which it cannot do whilst sufficient suppressed demand exists, but as a tool for estimating the socially desirable demand level on the roads as opposed to on the mass-transit systems. Road speeds in big, congested cities can only be increased by increasing the direct speeds of the mass-transit systems. Methods of achieving such increases are discussed.  相似文献   

7.
Abstract

This paper attempts to propose a framework on driving cycle development based on a thorough review of 101 transient driving cycles. A comparison of the driving cycles highlighted that Asian driving is the slowest but most aggressive while European driving is the fastest and smoothest. Further review of the cycle development methodologies identified three major elements for developing a driving cycle; test route selection, data collection and cycle construction methods. A framework was eventually proposed based on these findings and recommendations from this review. First, traffic activity patterns and quantitative statistics should be considered in determining the test routes. Speed data can be collected by using chase car method, on‐board measurement techniques or their hybrid. As for the construction of driving cycle, the matching approach has been more commonly used. It is recommended that the tendency of zero change in acceleration, which has been commonly ignored in the literature, and the application of succession probability at second‐by‐second level should be further explored. A fifth mode, creeping, is also recommended for modal analysis for characterizing urban congested driving conditions.  相似文献   

8.
In the course of Deutsche Bahn's new high - speed railway line between Nuremberg and Ingolstadt, a number of tunnels are being constructed, with a total length of about 15 km. One of the longest tunnel is the 7,250 m long Irlahüll tunnel.The tunnel was driven in karst geology. It was not expected that karst phenomena would be so widespread. This forced client, designer and contractor to take a new approach to the project. Different tools were developed to handle the problems on site. Additional site investigations had to be performed to identify karst phenomena in the vicinity of the tunnel. For validating the stability and serviceability of the tunnel, a new way of defining the probability of failure of the construction had to be found. Based on the experience of the tunnel driving at the high - speed railway line in Germany between Nuremberg and Ingolstadt, two different methods of tunnelling are discussed: Drill and blast ( New Austrian Tunnelling Method: NATM) and the use of tunnel boring machines (TBM).  相似文献   

9.
Kane  Lisa  Del Mistro  Romano 《Transportation》2003,30(2):113-131
The 1990s saw the emergence of influential transport legislation both in the UK and in the USA. This "watershed" period appears to indicate that a significant turning point in transport policy is underway. There is now a need to re-evaluate how transport planning is done, and to consider changes to commonly used methods. Criticisms of urban transport planning are traced in the paper. These often focus on the four-stage modelling approach, but some authors also criticise the "rational comprehensive" paradigmatical framework within which the use of four-stage computer models is situated. It is argued that the rational comprehensive model of thinking is less useful today, due to the increasing complexity of the transport planning exercise; the rejection by the public of the transport planner as "expert"; and the highly political nature of transport planning. Alternative approaches are needed in order to address the new types of problems which transport planners face. The use of one such alternative approach, the Soft Systems Methodology, is illustrated as suitable for investigating complex decision-making systems in transport planning. It is suggested that this method could be beneficial in other problematic transport planning situations where the rational comprehensive approaches prove inadequate. Finally, the paper briefly looks ahead and considers the implications of a changing policy environment to the training of transport planners in the future.  相似文献   

10.
Using four consecutive days of SITRAMP 2004 data from the Jakarta metropolitan area (JMA), Indonesia, this study examines the interactions between individuals’ activity-travel parameters, given the variability in their daily constraints, resources, land use and road network conditions. While there have been a significant number of studies into day-to-day variability in travel behaviour in developed countries, this issue is rarely examined in developing countries. The results show that some activity-travel parameter interactions are similar to those produced by travellers from developed countries, while others differ. Household and individual characteristics are the most significant variables influencing the interactions between activity-travel parameters. Different groups of travellers exhibit different trade-off mechanisms. Further analyses of the stability of activity-travel patterns across different days are also provided. Daily commuting time and regular work and study commitments heavily shape workers’ and students’ flexibility in arranging their travel time and out-of-home time budget, leading to more stable daily activity-travel patterns than non-workers.  相似文献   

11.
Abstract

For the last five years the technology factor (by which is meant both process and product innovation) has received renewed attention in the transport sector as society is confronted with new challenges. This leads to a call for change and transitions. Technology is considered as a potential answer to new needs and new problems, like the reduction of CO2 and the supply of alternative energy. It is important that there is a theoretical basis for the way of thinking on innovation and diffusion when it comes to technology dynamics. This paper, based on a literature study, addresses the question to what extent the theory of transition management can be considered as a new application of technology dynamics. The theory of technological innovations in the broad sense is analysed and applied to the transport sector.  相似文献   

12.
13.
Suburban sprawl has been widely criticized for its contribution to auto dependence. Numerous studies have found that residents in suburban neighborhoods drive more and walk less than their counterparts in traditional environments. However, most studies confirm only an association between the built environment and travel behavior, and have yet to establish the predominant underlying causal link: whether neighborhood design independently influences travel behavior or whether preferences for travel options affect residential choice. That is, residential self-selection may be at work. A few studies have recently addressed the influence of self-selection. However, our understanding of the causality issue is still immature. To address this issue, this study took into account individuals’ self-selection by employing a quasi-longitudinal design and by controlling for residential preferences and travel attitudes. In particular, using data collected from 547 movers currently living in four traditional neighborhoods and four suburban neighborhoods in Northern California, we developed a structural equations model to investigate the relationships among changes in the built environment, changes in auto ownership, and changes in travel behavior. The results provide some encouragement that land-use policies designed to put residents closer to destinations and provide them with alternative transportation options will actually lead to less driving and more walking.
Susan L. HandyEmail:

Xinyu (Jason) Cao   is a research fellow in the Upper Great Plains Transportation Institute at North Dakota State University. His research interests include the influences of land use on travel and physical activity, and transportation planning. Patricia L. Mokhtarian   is a professor of Civil and Environmental Engineering, Chair of the interdisciplinary Transportation Technology and Policy graduate program, and Associate Director for Education of the Institute of Transportation Studies at the University of California, Davis. She specializes in the study of travel behavior. Susan L. Handy   is a professor in the Department of Environmental Science and Policy and Director of the Sustainable Transportation Center at the University of California, Davis. Her research interests center around the relationships between transportation and land use, particularly the impact of neighborhood design on travel behavior.  相似文献   

14.
The purpose of this article is to present an optimization model to plan the deployment strategy for hydrogen refuelling stations in a city when Origin–Destination (OD) data are not available. This model considers two objectives: to maximize the traffic covered by the selected hydrogen refuelling stations and minimize the average distance of the city’s inhabitants to the nearest hydrogen refuelling station. As OD data are assumed to be unavailable, the clustering of stations in the highest traffic zones is prevented by a new constraint that takes into account information on the distribution of existing conventional refuelling stations. This model is applied to Seville, a city in Southern Spain of about 140 km2 with a population of around 700,000. This application uses the results of a survey of more than 200 Sevillian drivers on their current refuelling tendencies, their willingness to use alternative fuel vehicles and their minimum requirements (regarding maximum distance to be travelled to refuel and number of stations in the city) when establishing a network of alternative refuelling stations.  相似文献   

15.
Abstract

Railways restructuring takes place under very different circumstances and with very different goals in Western Europe, Central and Eastern Europe, and Russia. There are some improvements in productivity associated with the reforms in the European Union (among others access to infrastructure and vertical separation). But they are not certain to be replicated following similar restructuring in transition economies, especially if one takes account of the much higher shadow price on government subsidies in the latter. The current and proposed reforms in the railways of Central and Eastern Europe and Russia are described in detail; the likely outcomes of reforms in the special economic, regulatory and legal environments of these countries are analysed; and an alternative proposal for restructuring in Russia is presented.  相似文献   

16.
17.
Abstract

The institutional environment of rail transport has changed as a result of recent European directives, but the changes have taken different forms from one country to another. In the case of international maritime chains, the development of door‐to‐door services makes inland haulage from the loading and discharging ports extremely important, and it highlights the need to reshape the rail freight industry. This paper analyses the degree of involvement of different actors drawn from the maritime industry in developing and commercializing rail services in the changing regulatory environment. Several maritime operators, shipping lines, port‐handling companies and port authorities have been involved in some container rail services since the early days of liberalization. Their commitments take very different forms, however. Whereas contracts are mainly used for the provision of service, particularly for train haulage, integration by means of shareholding or creating subsidiaries or joint ventures is used for marketing. Important differences between France, the UK, Germany and the Netherlands are detailed. In the latter two countries, there is more involvement in the provision of rail services. Marketing rail services appear to be the main strategic issue for the maritime operators in all four countries  相似文献   

18.
The CCS Hydropower Station in Ecuador is a water diversion type power station, in which two superdeep vertical shafts with depth of 537.9 m are arranged. After comparison of alternative options, a new type of 1088DC RHINO raise boring machine was chosen to construct the vertical shafts. The construction process with the raise boring machine is divided into 3 stages, i.e. pilot hole construction by forward drilling, pilot shaft construction by reverse expanded excavation and shaft construction by manual expanded excavation. In view of the problems of buried drill bits and pilot hole deflection in the first stage, the problems of shaft collapse and cutter damage in the second stage, and the problems of collapse, water inflow and shaft blocking in the third stage, some preventive and treatment measures were proposed based on causes analysis, and good construction effect was achieved. The success- ful construction of super-deep vertical shafts at CCS hydropower station with raise boring method is significant to improve the construction level of deep shafts of domestic water conservancy and hydropower engineering, and the re- lated research can provide a reference for the similar shaft engineering construction. © 2018, Editorial Office of "Modern Tunnelling Technology". All right reserved.  相似文献   

19.
截至2011年9月,中国客车统计信息网的数据显示:1~9月全国50家客车企业累计销售客车169231辆,累计增量11268辆,增幅为7.13%。庞大的销量下,我们很难想象,55年前的中国,甚至连一辆"made inChina"的客车都没有!建国前到建国初期,上海百老汇门口,偶尔能看见几辆略显破旧又摇摇欲坠的大客车缓缓开过,车尾的铜  相似文献   

20.
For the bed rock of the foundation pit of the Bandar Malaysia North Station (BMNS) in Kuala Lumpur,the karst, fissure and cave are very developed, and curtain grouting, spud grouting and compaction grouting were conducted to achieve waterproofing and reinforcement. A Lugeon test and pumping test were carried out to test the grouting performance. The results show that the waterproofing effect of the Bandar Malaysia North Station (BMNS) is significant, meeting the basic requirements for waterproofing. © 2018, Editorial Office of "Modern Tunnelling Technology". All right reserved.  相似文献   

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