消除公交串车——一种基于GPS与GIS的实时控制方法

城市公共交通系统是一个包含人、车、路、环境、能量和信息的高度非线性的大规模复杂系统。公交串车问题严重降低了公交服务的可靠性，本文综合运用系统工程理论与方法，给出了公交串车与大间隔的定义，提出了公交串车与大间隔问题的成因分析模型、基于BP人工神经网络的行车间隔预测模型和基于GPS与GIS的实时动态反馈控制模型。最后，对北京公交300路车所采集的680组数据进行了实证分析。分析结果表明所使用的方法能有效地消除公交串车问题，同时也能为公交企业自身的运营管理和乘客的出行规划提供有价值的决策参考。     

Relationship between logistics infrastructure and trade: Evidence from Spanish regional exports

Geographical factors and transport infrastructure are two of the key determinants that influence international competitiveness. In this sense, the quality of such infrastructure and how widespread it is, the distribution and capacity of logistics facilities in a country, as well as the number of private operators and their degree of specialisation, all play an increasingly important role in the design of business strategies aimed at increasing a country’s share of the international market. Until recently, however, availability and access to logistics services have been considered secondary factors when defining business competitiveness. This paper estimates an augmented gravity model of trade that specifically includes logistics and transport infrastructure indicators as explanatory variables. The model is estimated by using bilateral exports from 19 Spanish regions to 64 destinations (45 countries and 19 Spanish regions) with data for the period 2003–2007. The findings show that logistics is indeed important for the analysis of trade flows in goods and they highlight the importance of logistics measures at the regional level. In particular, the number, size and quality of logistics facilities positively influence export flows.     

Generating synthetic baseline populations from register data

The paper presents a population synthesiser based on the method of Iterative Proportional Fitting (IPF) algorithm developed for the new Danish national transport model system. The synthesiser is designed for large population matrices and allows target variables to be represented in several target constraints. As a result, constraints for the IPF are cross-linked, which makes it difficult to ensure consistency of targets in a forecast perspective. The paper proposes a new solution strategy to ensure internal consistency of the population targets in order to guarantee proper convergence of the IPF algorithm. The solution strategy consists in establishing a harmonisation process for the population targets, which combined with a linear programming approach, is applied to generate a consistent target representation. The model approach is implemented and tested on Danish administrative register data. A test on historical census data shows that a 2006 population could be predicted by a 1994 population with an overall percentage deviation of 5-6% given that targets were known. It is also indicated that the deviation is approximately a linear function of the length of the forecast period.     

Workshop 3A: Governance,contracting, ownership and competition issues in public transport: Looking up not down

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.     

Workshop 6: The public agenda: What is working and what is missing

Workshop 6 topics covered social inclusion, the informal transport sector, transport in developing countries and sustainability. The strong connections and complimentary goals were noted, where solutions to social exclusion and greenhouse gas reduction can both be realised with good transport and urban planning. There is an opportunity for developing countries to avoid the transport mistakes in many developed countries, such as car dependence. This will involve the development of infrastructure that offers accessible public transport to the majority of people, providing resources to the informal transport system and integrating this with public transport. The workshop considered specific issues such as rural transport, new technology, car tolls to subsidise public transport, safety issues with informal transport and the failure to evaluate the longer-term impacts of many major transport infrastructure developments. Recommendations were made in relation to research and policy and future Thredbo topics.     

Mumbai Urban Transport Project – A multi dimensional approach to improve urban transport

This paper attempts to bring out the lessons learned from implementation of the Mumbai Urban Transport Project (MUTP), a World Bank financed project. While some of the problems and many solutions may be case specific, the lessons learnt would be of use for other similar interventions especially in similar urban settings. Even complex engineering challenges are generally easy to be surmounted, when compared with the bigger challenges like resettling the project affected peoples, managing several stake holders and institutions, bringing them together and they agreeing to do things differently.     

Analysis of thirty years evolution of urban growth,transport demand and supply,energy consumption,greenhouse and pollutants emissions in Greater Cairo

The objective of the paper is to analyze evolution of urbanization, transport demand and supply in Greater Cairo (GC) over the last three decades of the 20th century. This is in addition to investigating the impact of city growth on energy consumption and emissions from transport. It utilizes results of 1971, 1978, 1987, 1998 and 2001 travel demand surveys, undertaken during the corresponding GC transport studies; each was published a year or two later. No further transport studies have been carried out in GC over the past decade and in view of the current political situation, it is not envisaged that similar studies will be undertaken in the near future. The analysis includes the evolution of daily trips, trip purpose share, modal share and number of cars. More recent trends for 2006/2007 vehicle registration by type and size are given. The evolution of transport supply covers projects until early 2012. In parallel estimates of the evolution of energy consumption and cost, emissions of greenhouse gases (CO₂) and pollutants (CO, HC and NO_x) are given for 1971/2001. The adopted estimation methodology is summarized. Comparative analysis of relevant evolution indexes and trends of growth between 1971 and 2001, taking the former as base year, is given. Land use and transport policies and projects that in some cases helped, directly or indirectly, to reduce traffic congestion, or at least prevented an increase, are addressed, commenting on their outcomes. Thus, transferable experience are useful to sister cities benefiting from successes and avoiding drawbacks. The evolution of the impact of GC metro on energy consumption and cost, and GHG emissions is given for 1987/2001, assuming the scenario “metro did not exist”. More recent impact analysis is given for 2007/2008, as the data allowed estimating traffic volumes that would have been added to the congested metro corridors under the above scenario; and the related fuel consumption and cost and GHGs. The paper ends with conclusions on GC evolution, learned lessons and suggests repeating similar work in other mega cities of the developing countries. Further research is emphasized, e.g., modeling the relationship between land use, transport, energy and emissions; modeling emission factors by vehicle type; and studying fuel-subsidy-reduction scenarios and their socio-economic effects.     

How much can public private partnership really do for urban transport in developing countries?

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.     

Applying measures of modelling quality to a national time series: a benchmark for transport demand models

ABSTRACT

In current urban planning practice, macroscopic transport demand and assignment models are essential for the evaluation of mid- and long-term land use developments and infrastructure investments. The credibility of their projections strongly depends on their ability to reproduce present day traffic volumes. Obviously, a simplified model of reality will display some shortcomings, and the effect of these is asserted by quality measures that quantify the divergence from observed traffic volumes. There is, however, only rough guidance regarding acceptable ranges of these measures. Most of the literature on this subject approach these ranges from below, by discussing measures attained by operational models and using these as a benchmark, or by using the adverse effects of modelling errors to derive a minimum quality level. On the contrary, this study suggests upper limits for quality measures by analysing year-on-year variations in traffic volumes that result from changing land use and infrastructure.     

Exploring ‘weak signals’' as potential challenges in transport: an inventory of potential future technology developments

This article assesses the most likely technological developments in transport, not only by investigating current innovations but also by observing different approaches to confronting future developments. The article discusses technology forecasting and the meaning of environmentally sound technologies; some insights into technology development and the relevance of technological forecasting; the factors that influence technology development in transport; and, in this context, differentiation between exploration, expectation and forecasting. It goes on to identify, from four different perspectives, major developments of strategic relevance for the transport sector that might arise in the longer term. An assessment is made of the consequences of these observations for the implementation of innovations in transport.