Pedestrianisation: London's Oxford Street experiment

Oxford Street in London, is the capital's principal shopping street and famous throughout the Western World; it is also the most obvious route from the city of London to the West, the Midlands and the North of England.The conflict between its twin roles of shopping centre and major traffic route was demonstrated in its accident record which put Oxford Street top of the list of accident blackspots in London, whilst its location in the most fashionable area of London make the costs of new road construction prohibitive.A comprehensive accident analysis defined the pedestrian/vehicle conflict by time and place and facilitated the detail design of a limited traffic ban with associated rerouting.Considerable uncertainties in prediction of the resulting traffic conditions, in the absence of data on demand elasticity, dominated the design of the experiment and led to the inclusion of an avert chaos policy. Traffic predictions which included details of the probable manner in which congestion would spread were assisted by a new network simulation model developed by one of the authors and described here.The report outlines the history of the experiment from conception to implementation (in record time) and reports some early and generally encouraging results. On the strength of which the Greater London Council has confirmed the scheme (August 1973) and has announced plans for its extension to the remaining half of Oxford Street — from Oxford Circus to St. Giles' Circus — which still carries the full weight of traffic.Previously undertaking doctoral research at Imperial College, London.     

Transportation system in the future

The paper begins with a review of the major features of the transport policy of the European Community. It continues with an assessment of the likely characteristics of future transport supply, identifying the particular competing developments in road and air transport which would affect the success of high speed rail investments such as that proposed between Amsterdam, Groningen and Hamburg.     

珀金斯:永远把客户放在第一位

Perkins致力满足中国整机厂的需求,帮助他们攻克本土和出口市场。最终目标是要成为中国设备制造商的首选发动机供货商。     

On the semantic scale problem in stated preference rating experiments

Stated preference (SP) rating experiments are easy to design and conduct. Furthermore, they constitute a generalisation of SP choice experiments in terms of the information about preferences that can be achieved. However, its results are sensitive to the numerical values assigned by the analyst to the semantic scale used by individuals to express their preferences. We consider this problem in depth using a variety of statistical techniques, including ordinal probit and a novel optimal scale linear regression approach.     

A Review of Modelling Methods for Railway Vehicle Suspension Components

The dynamic behaviour of railway vehicles has been the subject of study for over a century but the advances in computing technology in the last few years have led to a very rapid development in the use of numerical techniques for solving railway vehicle dynamics problems. As these techniques have developed, and have been applied to ever more complex problems, the modelling of the vehicle components has increased in importance. Mathematical models of railway vehicles may now include components such as swing links, air-springs, trailing arm suspensions, load sensitive friction dampers, rubber bushes with hysteresis etc, all of which require sophisticated modelling techniques to produce accurate results. This paper looks at the developments that have taken place in this area, the background to the need for sophisticated models, the improvements in accuracy that can result and some of the difficulties in applying these techniques to the modelling of real situations.     

Directional Stability of Truck-Dolly-Trailer System

The present state of knowledge on the handling behaviour of truck-dolly-trailer system is based on parametric studies made through simulation or eigen value analysis. Any convincing study using the equations to the stability boundaries have not been reported so far due to algebraic complexities. This paper fills the gap. Effects of system parameters are assessed using equations to the stability boundaries obtained from Routh-Hurwitz criterion. The system equations of motion are derived from a bondgraph model of a linearised system.     

Use of duration models for predicting vehicular delay at a US/Canadian border crossing

Delays caused by congestion at the US/Canadian border crossing between Washington state and British Columbia have underscored the need for some sort of intervention. One obvious congestion-mitigation measure would be to estimate delay times and then relay this information to motorists so that they could select among alternative border crossing sites, or delay their trips. This paper applies duration models to estimate vehicular delay and demonstrates the usefulness of such models as a basis for a fully automated motorist information system. The paper also explores the flexibility of duration models, in providing estimates of vehicle delay, by using alternate parametric forms and assessing prediction accuracy.