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1.
The term Demand-Responsive Transport (DRT) has been increasingly applied in the last 10 years to a niche market that replaces or feeds (usually via small low floor buses or taxis) conventional transport where demand is low and often spread over a large area. More recently, the concept of DRT as a niche market has been broadened to include a wider range of flexible, demand-responsive transport services and is increasingly referred to as Flexible Transport Services (FTSs). The contention of this paper is that well-implemented FTS has the potential to revitalise bus-based public transport services which are traditionally based on fixed networks with variable geographical coverage and levels of service.  相似文献   

2.
A few cities in some of the larger developing countries in Latin America and Asia have made increasing use of multi-year concessions or franchises, competitively awarded to private companies, for construction and operation of urban transport infrastructure and for provision of public transport services. In view of the strong prospective growth of developing-country cities with large transport needs, and the rise in the emerging economies of potential new sources of private capital, it is important to see how effective PPP has so far been in this area. The experience is analyzed principally by thorough comparative review of what has actually happened for some of the main users to date: Bogotá, Santiago, São Paulo, Seoul, and several cities in both China and India. Despite delays and mistakes that have been made in development of most of the projects, the overall results, already delivered and in prospect, are very positive and urban public transport is benefiting substantially, with significant side effects on poorer people's access to work and to services, air pollution levels and road accident rates. The widest and most important advantage of the PPP arrangements, as compared with more conventional short-term contracting, is found to be the innovations, technical and managerial, developed, and, in particular, the mutual capacity building of the countries' private and public sectors and their more effective interaction. The experience in the six countries covered suggests that other developing-country cities may be best assisted to develop sound urban transport PPPs more rapidly through provision of help on chosen items among 7 elements that have proved particularly crucial but sometimes weak in the projects reviewed: Civic consultation systems, Land-use/Transport strategic planning, Land/property market management, Monitoring systems, Progressive policies, Economic regulation, and Public institutional framework for PPPs.  相似文献   

3.
基于IEEE1588的分组传送网同步技术研究   总被引:1,自引:0,他引:1  
分组传送网(PTN)是具备传送功能的分组网络,它需要与公共交换电话网(PSTN)互通以及承载3G基站业务,文章分析了PTN对同步的需求及其重要性,介绍了分组网同步的标准化及关键技术,探讨了基于IEEE1588的PTN同步的解决方案。  相似文献   

4.
Land use/transport models and economic assessment   总被引:1,自引:0,他引:1  
This paper discusses the economic assessment of policies using land use/transport models. It argues that conventional forms of assessment focussing only on transport changes can underestimate the economic benefits of a policy. The paper argues that the benefits need to be measured by the changes of prices at the end of a trip and not just by the changes in travel costs. Models that do not estimate the changes of prices at the end of a trip cannot properly assess the impact of a policy.The model used in this paper is based on the MEPLAN software and estimates the location of households and employment and the interaction between them. It also estimates the cost of living for households and the production costs for employment. With these costs, it is possible to calculate the wider economic benefits beyond transport.The paper illustrates the assessment of policies for the Cambridge sub-region involving investment in public transport, orbital highway and congestion charging policies. The results forecast by the model are assessed in terms of the conventional cost-benefit using traveller’s surplus as benefits and compared with a wider assessment measure of compensation variation. It demonstrates that the last measure encompasses the wider benefits associated with transport policies which are not taken into account in conventional cost-benefit analysis.  相似文献   

5.
A number of South African cities are planning integrated public transport networks that rely on the introduction of Bus Rapid Transit (BRT), in line with similar trends to expand or upgrade public transport services in emerging and industrialised urban transport markets around the globe. In addition, BRT in South Africa is being used as a mechanism to drive reform in the dominant yet highly fragmented paratransit sector, inspired by similar processes particularly in Latin American cities such as Bogotá, Mexico City, and Santiago de Chile. Thousands of paratransit operators would have to formalise their businesses, or merge into new or existing operator entities in order to participate in the new systems. There is, however, an absence of accessible business plans and regulatory regime proposals around which paratransit can be engaged to convince it to alter its current modus operandi. A large number of national, regional and local paratransit groupings have furthermore indicated their resistance to the planned networks on the grounds of insufficient consultation, an unclear future role in the system and employee redundancies. Should this deadlock not be resolved, it seems unlikely that the planned networks will be realised in the proposed timeframes, if indeed at all. This paper investigates the South African passenger transport policy framework that has contributed to the current deadlock, and explores appropriate approaches to engaging paratransit operators on a system of contracting, competition and ownership that recognises the sector’s aspirations and fragmented nature, yet contributes towards improved passenger transport services. It is the authors’ view that paratransit reform is a highly context-specific process, even at the sub-city level, and that this could prevent transferring paratransit regulatory and integration approaches across countries, and even cities in the same country, without adaptation to local conditions.  相似文献   

6.
The topic of social inclusion is now maturing in the Thredbo conference series, being viewed as an important consideration in many aspects of land transport, the benefits extending beyond the socially excluded targeted population. The social inclusion workshop included presentations on new empirical evidence on the value of providing those at risk of social exclusion with mobility options, and how this links to improvements in personal wellbeing, often through mediating influences such as social capital. Work was presented on the role of transport services specifically targeted to those at risk of exclusion, particularly taxi services and school bus services, as well as how to modify fare structures to maximise inclusion in an efficient, mature transport system. The value of Universal Design principles to groups both at risk of being excluded as well as the current travelling public, was shown. The workshop affirmed the importance of including these wider benefits of inclusion in cost-benefit evaluations of transport. The issue of how best to move knowledge into strategic and operational policy, and the transferability of both knowledge and policy between different countries and settings, was discussed. This paper concludes with suggestions arising from the workshop in relation to policy and research, as well as recommendations for Thredbo 12.  相似文献   

7.
Workshop 3A focussed on matters of institutional design that seem likely to improve public transport outcomes. It started by defining high level outcome goals, as measures of ultimate public transport success, and then identified the major societal issues that public transport systems can help to resolve. These issues were separately defined for Southern African and western settings. The importance of taking an integrated approach to transport, particularly land use/transport integration, was seen as fundamental to goal achievement. Workshop papers provided many and varied examples of this importance, ranging from PPPs for major public transport projects to system design issues and contracting out of services. The Workshop included detailed discussion on paratransit development in Southern Africa, where relationship management is proving to be critical, in-line with much previous Thredbo discussion about the important role of trusting partnerships. Parallels and contrasts were drawn with paratransit in western settings. Competition in passenger rail was also a focus, with some questioning of the benefits of franchising. Discussion concluded by proposing recommendations for policy and research and suggesting agenda items for future Thredbo Conferences.  相似文献   

8.
During the past 15 years competitive tenders have become a common procedure when procuring local bus services in Europe. In particular, tenders with gross cost contracts and the so-called Scandinavian model have gained popularity, resulting in a vast amount of research on optimal contractual relationships between government and operators. This paper pays attention to a rather neglected part of the Scandinavian model: the construction of professional procuring bodies and their relationship to the local public administration, focusing on its implications for policy steering and service performance.The paper outlines briefly two different perspectives of analyses of organisational models: one perspective is anchored in principal-agent theory and institutional economics; and the other perspective in political science. Empirically, the article is based on an evaluation of the relation between two Norwegian counties and the administrative company responsible for planning and procuring public transport services. This evaluation indicates, firstly, important common challenges for the county administration due to lack of regional administrative competencies in relation to the administrative company, which also hampers the county’s role as coordinator of policy areas of importance for public transport. Secondly, due to increased transaction costs, the establishment of administrative companies does not seem compatible with contracts relying on net cost solutions with huge scope for operator initiatives.  相似文献   

9.
This paper updates results of an international study aimed at quantifying the links between transport disadvantage (TD), social exclusion (SE) and well-being (WB) in Melbourne, Australia. The study extends knowledge associated with SE and transport by quantify social and behavioural implications of lack of public and private transport and the nature of the social WB benefits associated with improving services.Study aims and methodology are outlined. Recent findings covered relate to car ownership on the urban fringe, patterns of transport disadvantage, the analysis of time poverty related to transport disadvantage, measuring the economic value of additional mobility and use of a Structural Equation Model (SEM) to relate WB and SE to TD and a series of explanatory factors.Overall results suggest that those without a car on the urban fringe adjust well with their circumstances by living close to activity centres. They demonstrate sustainable choices, trading off budgets and home location to balance mobility and accessibility. Poorer households with high car ownership value mobility and cheaper more remote fringe dwellings but demonstrate numerous strategies to reduce high car costs which are acknowledged as a significant burden. Analysis identifies 4 key types of transport disadvantage including a ‘vulnerable/impaired’ group which should be of much greater concern for targeted policy than others due to poor scoring on SE and WB scales. The economic value of new mobility is also explored with results suggesting $AUD 20 per average new trip which is four times larger than conventional values for generated travel.Analysis has also suggested that transport disadvantage can relate to socially advantaged as well as socially disadvantaged groups through time poverty. This was found to be an important mitigating factor when relating TD to WB. A statistically reliable structural equation model is developed suggesting the SE-WB link is strong (−.87) with a modest link between TD-SE (.27).Areas for future research in the project are also summarised.  相似文献   

10.
吴建华 《船舶》2012,23(2):58-59,74
针对舰船通信中大容量接入以及多种业务网络融合的应用需求,提出采用电路交换平台结合RPR光纤环网传输平台的全新舰船解决方案,不仅提供了大容量系统接入能力,同时将各种网络设备汇聚到统一的网络传输平台上,实现了多种业务数据的统一承载,极大提高了系统的可靠性、灵活性。  相似文献   

11.
During the last forty years, Santiago has experienced a series of drastic changes in public transport policies. These changes have ranged widely, from total deregulation to processes that concentrated the management of public transport within the hands of the public sector.  相似文献   

12.
The 1998 White Paper proposed integration as the solution to Great Britain’s land transport problems. Most commentators agree that this much vaunted New Deal for Transport has been a failure. Yet some ten years later policy papers from bodies such as the Institution of Civil Engineers and the Centre for Cities are still proposing integration as a possible panacea.There are a number of reasons for the failure of integrated transport over the last decade. The first is the failure to define the concept. The second is the failure to operationalise the concept. The third is the lack of an evidence base on the success of integrated transport policies. Evidence is now emerging in Britain on the benefits (and indeed the costs) of some aspects of integrated transport policies. The fourth, and perhaps the most crucial, is the lack of will in terms of politicians, civil servants and the public at large, to adopt the behavioural changes necessary for an integrated transport policy to be successful. A series of organisational and funding changes are proposed that could advance the prospects for integration.  相似文献   

13.
综合网络管理体系结构研究   总被引:1,自引:0,他引:1  
文章用UML语言描述了综合网络管理系统,并采用Web Services技术对其框架结构进行了设计,最后分析了综合管理系统的本地管理流程和上下级管理流程。  相似文献   

14.
One main theme of European Union’s in transport policy statements has been the increased role of railways in the reducing environmental impacts and costs of transport activity. One option to increase the modal share of rail transport is to utilize the dry port concept, particularly applicable to general cargo. At the Port of Gothenburg (Sweden) use of this concept in combination with rail transport has led to a reduction of CO2 emissions, and lower transport energy costs. The main objective and motivation of this research work are to examine through analytical models, how this same dry port concept could be implemented in the Finnish transportation network, with estimates of the benefits being gained.The research method of this study is macro gravitational models of distribution. Main input data for the models are distances and population in the area. The approach aims to research, how relative transport costs behave by increasing the number of dry port distribution locations. For the actual computation work the authors apply linear integer programming. Based on the results, the authors argue that relative transport costs can decrease considerably by increasing the number of dry ports, up to the level of six locations. This is considerably less than what is the current situation in Sweden. The found solution also differs from Sweden as the fragmented Finnish seaport system enables using numerous seaports instead of one, which further decreases inland transportation distances and volumes considerably. At the same time forthcoming sulphur emission reduction regulation (for sea transports) might impact the transportation network structure by decreasing sea transport and the number of seaports used. This might lead to a further increase in land-based hinterland transport.  相似文献   

15.
India is in the course of an economic transition. The economic growth nurtured the life in the cities and cities have become a major livelihood destination for everyone. This migration of people contributed to the increased urbanization of Indian cities. The booming economy fostered the well-being and shaped the lifestyle of people in such a way that the dependency on private vehicle has become an unavoidable affair. Along with population growth, the increased vehicle ownership gave rise to overall spurt in travel demand. But the supply side lagged behind the demand adding to many of the transport related externalities such as accidents, congestion, pollution, inequity etc. The importance of sustainability is understood in the current urban transport scenario leading to the development and promotion of sustainable transport polices. The core agenda of these polices is to target the travel behavior of people and change the way they travel by creating a different travel environment. However, the impacts of many such policies are either unknown or complex. Hence, before adopting and implementing such policies, it is important for the decision makers to be aware of the impacts of them. The role of travel demand models comes here as they predict the future travel demand under different policy scenarios. This paper reviews the ability of travel demand models applied in India in analyzing the sustainable transport policies. The study found that the conventional model system in India, which is trip based four step aggregate methodology, is inadequate in analyzing the sustainable transport policies. A review of alternative approach, known as activity based travel demand modeling found that they are capable of handling such policies better than conventional models and are assistive to the decision makers in arriving at right mix of polices specific to the situations. Since there is no operational activity based travel demand model system developed in India, the study at the end envisaged a conceptual framework of an integrated activity based travel demand model based on the requirements identified from the review. This can potentially replace the existing travel demand models and can be used for planning applications once the modification & validation have been done according to the existing activity-travel behavior of individuals.  相似文献   

16.
Bus based public transport has enjoyed revitalisation in many urban areas but outside large towns and cities its provision and quality remains erratic. Many rural settlements have infrequent services giving rise to social exclusion through transport disadvantage.The UK Government highlighted a need in Towards a Sustainable Transport System (2007) for radical new thinking on rural accessibility to help meet goals of quality of life and accessibility for all and to help meet the challenge in finding carbon friendly ways of meeting rural transport needs. This paper reports work undertaken for the Commission for Integrated Transport, an advisory body to UK Government, on how shared taxi-schemes could be developed within a deregulated environment to meet rural accessibility needs. This is based on an analysis of institutional barriers and comparison between successful mainland European schemes and UK schemes. The paper considers economic viability and the levels of subsidy currently used to provide accessibility in rural areas to show the potential for making current expenditure on rural transport in the UK ‘work harder’ to deliver a collective taxi-based service as part of the public transport mix so as to increase rural accessibility.  相似文献   

17.
A wide range of contractual arrangements are increasingly being used by the public sector to materialise the delegation of transport infrastructure provision tasks to the private sector, over long periods of time. This paper addresses the issue of transport infrastructure regulation in the specific context of public-private settings. Starting by the discussion on the concept of Public-Private Partnership (PPP) it is stressed that, despite the different meanings that can be found in the literature, it is possible to define a PPP by using a core group of characteristics, such as the bundling of services and the transference of a relevant part of the risks to the private sector on a long term basis. Regarding the action of the regulator, we look at three dimensions of efficiency that are expected to be pursued at the strategic level of regulatory action. However, it is acknowledged that the regulatory function is in practice rather complex since it requires balancing a multiplicity of other objectives or goals, which may vary according to specific economic conditions. In the domain of pricing, the review carried out suggests that since “first best” assumptions are not met in the “real world” it hardly seems possible that the short run marginal cost pricing “canon” could be directly used to shape pricing policies. Consequently, when considering the application of the standard neoclassical marginal cost pricing approach it is pertinent to ask whether the second best solutions can lead to efficient outcomes that might be accepted by the stakeholders. Bundling construction and maintenance tasks into a single long term contract, which is a typical characteristic of “standard” PPPs, could theoretically bring cost benefits since it allows for the possible internalization of any positive externalities that may be generated during the whole project life cycle. The economic rationale for the bundling of construction/maintenance with financing services is that it enhances the likelihood of submission of realistic bids at the procurement stage. In addition, the chances of the contractor sticking to the agreed contractual terms, after contract award, are potentially increased given the higher exposure to financial risk.  相似文献   

18.
中国进口原油海运系统研究   总被引:1,自引:0,他引:1  
随着中国原油消费量的快速增长和国家原油储备计划的实施,原油进口量逐年剧增。原油进口公司对于如何合理安排运输线路来降低进口运输费用的问题非常关注。根据我国原油进口运输以租外轮为主的现实情况,建立改进的运输问题模型,选择典型航线建立原油运输网络,并对其最优化。优化的结果可作为今后中国进口原油运输的参考。  相似文献   

19.
The past emphasis in this conference series has been on the best ways to deregulate regulated public transport markets. This workshop reverses this process by examining the best ways to regulate deregulated public transport markets. A hierarchy of regulatory needs is identified and three hybrid models examined, based loosely on experience from Great Britain, New Zealand and Sweden. It is argued that deregulated public transport markets are a global phenomenon but regulatory measures should reflect local requirements. The resultant process of glocalisation might result in regulatory measures that focus on the rules of law and their enforcement in emerging public transport markets (such as urban transport in Sub Saharan Africa and for the soon to be competitive inter urban market in Germany) but that focus on guidance for network integration and incentivisation for welfare maximisation in more mature public transport markets (as in Great Britain, New Zealand and Sweden).  相似文献   

20.
Recent transport sector liberalisation, as well as global economic crisis, is favouring the implementation of transport infrastructure projects through Public–Private Partnerships (PPP). However, there is a debate as to whether PPP schemes are a better option than conventional procurement. To this end, an evaluation framework is proposed, to assess which of these two alternative schemes for transport projects financing is preferable for the public. The proposed framework is complimentary to the Value for Money (VfM) approach and is based on a Multi Criteria Analysis (MCA). The first step is the estimation of the Public Sector Comparator (PSC) for the case of conventional procurement, dealing with construction, maintenance and operation costs revenues, as well as any costs associated with risks undertaken by the public. As for the PPP case, it includes any payments by the public sector and related risks costs. The MCA is then applied only if the PPP is found preferable for the public sector. The latter considers additional impacts, including among others the social attributes of a particular scheme, job creation, environmental impacts and safety and security aspects. The proposed framework was applied to a pilot Bus Rapid Transit (BRT) corridor infrastructure project in the city of Indore, India, in order to demonstrate its validity. The framework and its application could provide useful guidance when considering PPP for a transport project, since it demonstrates in a transparent way the society's attitude towards this project, something that is critical to its acceptance.  相似文献   

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