The impact of a new rapid transit system on traffic on parallel highway facilities

This study analyzes data of traffic crossing San Francisco Bay and passing through the Berkeley Hills via Caldecott Tunnel to determine the effect of the opening in 1974 of the Bay Area Rapid Transit System (BART) transbay line. There was a sudden shift in trend lines in 1974; vehicle volumes dropped, transit patronage jumped, but total person trips in the short run followed roughly the trends of the previous eight years. Since 1974, the growth rate in person trips through the Berkeley Hills appears to have remained about the same, while transbay vehicle and transit traffic have increased at a more rapid rate. The increase in transit patronage is particularly noticeable between the morning and afternoon peaks and probably represents new trips by shoppers and sightseers. Whereas other factors, such as the increase in the price of gasoline between October 1973 and July 1974 may have contributed a little to the sudden change in the long‐range trends in 1974, it is believed that the major cause was the opening of the BART network to transbay travel.

     

Route structures in air transportation—the situation in the federal republic of Germany

This paper deals with route structures in air transportation in general and describes the derivation of such structures. Based on an extensive analysis of scheduled air traffic in Germany, an overview of the situation in domestic and international air travel is given. In particular, relationships were found which permit—in connection with a number of influencing factors—to derive from the present situation route structures, which are also valid for a future year.

This approach was used for the assignment of origin‐destination‐passenger flows to air network routes in a forecast of demand and services in commercial air transportation of the Federal Republic of Germany for the year 1995.     

Constructing Time‐Scaled Maps: Switzerland from 1950 to 2000†

Abstract

The article discusses the construction of a time‐scaled maps series for Switzerland documenting the shrinking of the country since 1950. It describes underlying network models and the mathematical approach employed for the necessary rescaling. In conclusion, it presents the maps and discusses how the country was shrunk by half.     

Automatic ticketing on London underground

London Underground is currently going through a revolution in its fare collection systems. Magnetically encoded tickets are being introduced, obtainable from ticket office or self‐service machines, which are then checked automatically at start or finish of journey in the Underground's central zone. The microprocessor controlled equipment handles all accounting aspects of fare collection, because it is all part of a computer‐based network with centralized monitoring and control. The machinery was progressively installed from April 1987 to December 1988. This paper describes the history of the system, describes the new ticket and issuing machines, as well as discussing the development and project management tasks involved.     

Data attribution and network representation issues in GIS and transportation

Geographic Information System (GIS) is an “intelligent” technology which integrates attribute data and spatial features and manages the relationship between them. GIS is widely used in many activities, but its application in transportation is less common. The extension of GIS into transportation (GIS‐T) offers the potential to integrate transportation data into GIS. The integration of transportation data in GIS faces a number of barriers that are discussed in the paper. These barriers can be broadly categorized into data attribution and network representation issues. This paper analyzes these issues and reviews the potential for overcoming these constraints with current GIS technology. A fully developed GIS‐T has to meet many diverse needs including transportation inventory, modeling and operational problems. If GIS is to succeed as a transportation technology, it must be capable of integrating different levels of network representation and data attribution and have the ability to link with other transportation technologies.     

Integrating GIS concepts into transportation network data structures

Transportation network data structures must be designed to meet the requirements of the analyses being conducted and must be compatible with the selected graphical user interface. Increasing interest in geographic information systems (GIS) and intelligent transportation systems (ITS) have further burdened the network data structure. It is possible to implement object oriented programming (OOP) technology to satisfy these needs, without making the data structure excessively complicated.

This paper shows how a well‐developed network data structure can incorporate major capabilities normally associated with stand‐alone GIS's. The design of a network data structure derives from both theoretical and practical considerations. A design of a network data structure, composed entirely of objects, is presented. Examples of its implementation, limitations, advantages, and possible extensions are drawn from experience with the General Network Editor (GNE).     

International experience with speed limits during and prior to the energy crisis of 1973–4

This paper presents an artificial neural network (ANN) based method for estimating route travel times between individual locations in an urban traffic network. Fast and accurate estimation of route travel times is required by the vehicle routing and scheduling process involved in many fleet vehicle operation systems such as dial‐a‐ride paratransit, school bus, and private delivery services. The methodology developed in this paper assumes that route travel times are time‐dependent and stochastic and their means and standard deviations need to be estimated. Three feed‐forward neural networks are developed to model the travel time behaviour during different time periods of the day‐the AM peak, the PM peak, and the off‐peak. These models are subsequently trained and tested using data simulated on the road network for the City of Edmonton, Alberta. A comparison of the ANN model with a traditional distance‐based model and a shortest path algorithm is then presented. The practical implication of the ANN method is subsequently demonstrated within a dial‐a‐ride paratransit vehicle routing and scheduling problem. The computational results show that the ANN‐based route travel time estimation model is appropriate, with respect to accuracy and speed, for use in real applications.     

The demand for public transport. part II. supply and demand factors of public transport

Abstract

This two‐part article, concerned with the way public transport ridership is affected by the various relevant factors, is based on the Executive Summary of The Demand for Public Transport (Webster and Bly 1980), the report of the TRRL‐sponsored International Collaborative Study on Factors Affecting Public Transport Patronage. Part I of the article, which was concerned with the social and economic conditions in which public transport operates, showed the importance of the background factors such as income, car ownership and land use on public transport usage: it also indicated how the longer‐term impacts of the more direct demand factors (fares, service levels) often show themselves in changes in car ownership levels, activity patterns (i.e. where people live, work, shop, socialize, etc) and land‐use development.

Part II reviews the current state of knowledge on the effects of changes in fare levels and quality of service and of the introduction of various traffic and transport measures (traffic restraint, bus priority, etc): it outlines current methodology on costing public transport services and draws the supply and demand sides together in a consideration of particular strategies which are at the disposal of the operator, the planner and the policy maker.     

Social and political implications of new transport technologies

The mechanism of change in society is discussed in terms of power and interest groups, and some of the past changes in transport technology are examined in terms of the degree of threat posed to the established order and the interest groups benefiting from change. On the basis of such a power/benefit model, three of the new transport technologies which have been proposed — “guideway”, “dial‐a‐bus” and “network cab”, are discussed as to their likely social and political acceptability.     

Recent developments in traffic flow modeling using macroscopic fundamental diagram

ABSTRACT

This paper presents an overview of the recent developments in traffic flow modelling and analysis using macroscopic fundamental diagram (MFD) as well as their applications. In recent literature, various aggregated traffic models have been proposed and studied to analyse traffic flow while enhancing network efficiency. Many of these studies have focused on models based on MFD that describes the relationship between aggregated flow and aggregated density of transport networks. The analysis of MFD has been carried out based on experimental data collected from sensors and GPS, as well as simulation models. Several factors are found to influence the existence and shape of MFD, including traffic demand, network and signal settings, and route choices. As MFD can well express the traffic dynamics of large urban transport networks, it has been extensively applied to traffic studies, including the development of network-wide control strategies, network partitioning, performance evaluation, and road pricing. This work also presents future extensions and research directions for MFD-based traffic modelling and applications.     

An assessment of the demand for new transport technology in Australia

This paper summarizes the constraints which a technological innovation in transport must satisfy if it is to achieve widespread application. The existing and likely future travel demands in Australia are reviewed, and for certain types of travel it is concluded that existing modes may become unsuitable or unacceptable. In these areas, it is possible that a new transport technology may find application. In all other areas, it is considered that existing modes, or their functional successors, will continue.

Five possible demand areas in which new transport technology may find application are identified. These are as follows:

1) High speed distribution systems may be introduced in Australian CBD's (Central Business Districts) within the next ten years. These may be progressively extended to provide radial public transport services to the CBD. It is also possible that these systems may eventually be extended to provide a dual‐mode capability in inner‐suburban areas as a partial alternative to freeway construction.

2) New town developments which may be introduced in Australia could include various forms of advanced transportation systems.

3) New aviation modes, possibly including short take off and landing aircraft operating from suburban airports may be introduced to cater for inter‐urban travel.

4) A demand‐responsive transport system to cater for the needs of the transport poor in urban areas may find limited application.

5) In the longer term, possibly by the turn of the century, an improved transport system capable of providing door‐to‐door service over the whole of an urban area and operating under a dual‐mode configuration appears to be possible. It probably would emerge from development of an incremental nature and eventually include the installation of a new technology in the then existing freeway and railway reservations in the city.     

Evacuation Modelling in the United States: Does the Demand Model Choice Matter?

Abstract

This paper reviews the literature on the evacuation demand problem, with an emphasis on the impact of various modelling approaches on network‐wide evacuation performance measures. First, a number of important factors that affect evacuee behaviour are summarized. Evacuation software packages and tools are also investigated in terms of the demand generation model they use. The most widely used models are then selected for performing sensitivity analysis. Next, a cell‐transmission‐based system optimal dynamic traffic assignment (SO‐DTA) model is employed to assess the effects of the demand model choice on the clearance time and average travel time. It is concluded that evacuation demand models should be selected with care, and policy makers should make sure the selected demand curve can replicate real‐life conditions with relatively high fidelity for the study region to be able to develop reliable and realistic evacuation plans.     

A Multiple Criteria Decision‐Making Approach for Prioritizing Accident Hotspots in the Absence of Crash Data

Abstract

In an efficient transportation system, traffic safety is an important issue and it is influenced by many factors. In a country like Iran, until now safety improvements are mainly concentrated on road engineering activities, without much attention for vehicle technology or driving behaviour. One important aspect of road safety engineering activities is the so‐called treatment of hotspots or dangerous accident locations. Until recently, accident hotspots were identified and remedied by the esxperts’ personal judgements and a handful of statistics without taking into account other important factors such as geometric and traffic conditions of the road network. This paper therefore aims to define and identify the criteria for accident hotspots, then giving a value to each criterion in order to develop a model to prioritize accident hotspots when traffic accident data is not available. To do this, the ‘Delphi’ method has been adopted and a prioritization model is produced by the use of a ‘Multiple Criteria Decision‐Making’ method. The procedure is illustrated on a collection of 20 road sections in Iran. In addition, the model is validated against an existing database of road sections containing safe locations and hotspots. Finally, a sensitivity analysis is carried out on the proposed method.     

Network models in traffic management and control

Abstract

The context for network modelling in traffic management and control is described in terms of the current area‐wide nature of traffic management and the range of objectives to which it can contribute. Representation of a road system and traffic management measures in terms of nodes and links and parameters associated with them is described. It is shown that the pattern of traffic has to be represented not only in terms of flows on links of the network but also in terms of numbers of movements per unit time between points of entry to and points of exit from the area being modelled. In modelling so far, these numbers of movements are regarded as given, but the routes taken are estimated by traffic assignment. Models can so far be used for comparison of a range of given schemes and for optimization of traffic control within a scheme. Variation over time is a central feature of the modelling, and this requires the use of time‐dependent queueing theory, and the specification of numbers of movements for a succession of periods of between 10 and 30 minutes. Theoretical approaches to the resulting problems of modelling and optimization are discussed, and the ways in which these are supplemented by heuristic methods in currently available models is described. Some requirements‐for further research are outlined.     

Passenger waiting time and information acquisition using automatic vehicle location for verification

Bus riders utilize a variety of information media to learn how to travel to their destinations and to learn when they should arrive at bus stops. As part of the OCTA (Orange County Transit Authority) Transit Probe evaluation, 1199 passengers were surveyed to measure relationships between information acquisition and waiting time. A unique aspect of the survey was that some of the data could be correlated with automatic‐vehicle‐location (AVL) measurements of bus lateness at stops. Insights are provided as to the types of information riders acquire based on the nature of the trip and demographic characteristics. Insights are also provided as to factors affecting perceived waiting time. We found age group, whether a person needs to arrive at a destination by a specific time, primary language, and whether the person is a first‐time user of the bus line to be significant causal factors.     

Man and his transport behaviour Part 4a. User response to price changes: application of the ‘threshold’ concept

Summary

(1) The response of an individual consumer to change in such characteristics as price will be to change behaviour at a critical point, a ‘threshold’ at which a change of behaviour is perceived to be beneficial.

(2) Most choices can be viewed as binary, for example, between pairs of transport modes. A cumulative normal distribution of responses will give an S‐shaped curve, the mid‐point being at the average threshold value.

(3) An aggregate demand curve should show the response of a given group of people to a range of price changes at one point in time. Most curves derived from revealed behaviour do not permit this. To some extent, a demand curve must be derived from interviews and other tests, giving hypothetical behaviour. Such methods are used in non‐transport consumer tests, and work by Brög et al. gives a similar picture for transport users, supporting the concept of the S‐shaped curve.

(4) Allowance for frequency of trip‐making modifies this picture, suggesting that a smoother curve may be appropriate for some conditions, such as non‐work trips. These approaches may be combined by use of catastrophe theory, with two control factors. The hysteresis effect is found around the threshold where repeated changes in the basic stimulus produce successively smaller responses.

(5) There is some evidence of symmetrical response by public transport users to real increases and reductions in cash‐paid graduated fares, but this is not the case where different forms of pricing are involved.

(6) An example of threshold effects in private transport may be found in the monitoring of tolls on the Itchen Bridge by Atkins. Demand became particularly sensitive to price in a certain range.

(7) In the public transport field, there is similar evidence from the experience of introducing flat or zonal fares where graduated fares previously applied. Where travelcards are sold, the effect is much greater, and cases such as the West Midlands show little if any effect on sales despite real price increases. Here, trips are about 7% higher than would have been expected for the same revenue target, had graduated fares been retained. However, it may well be possible to exceed the threshold, especially where fares simplification and increases are combined, as the Trondheim experience suggests.     

Selatm — a GIS based program for evaluating the safety benefits of local area traffic management schemes

Particular safety problems relate to traffic on local streets. Local Area Traffic Management (LATM) schemes are often implemented with the objective of counteracting these safety problems. One analytical difficulty in appraising the effectiveness of LATM in dealing with safety problems has been the ‘footloose’ nature of accident locations in a local street network. Seldom are there distinct ‘blackspot’ locations. An area‐wide approach is needed and the interaction between the system and arterial road network must be considered. The paper describes the development of a Safety Evaluation Method for Local Area Traffic Management (termed SELATM). It is a GIS‐based program for analysing accident patterns over time and the evaluation of the safety benefits of LATM schemes. The evaluation is perform at different network levels for various accident variables. The thrust of the program involved the integration of network data with data on accidents and the installed devices to generate summary accident statistics for the various network levels allowing for before and after comparison with a control area. This program as developed is applied to a LATM scheme at Enfield, a suburb in metropolitan Adelaide.     

Inland waterways—their role and significance in European transport

Summary

1) Western Europe has a navigable waterways‐network of about 19,000 kms. For the coming decades, however, about 40 percent of the length of these waterways has a very limited relevance, because of the small capacity of the barges that can pass along them.

2) Of the different types of barges the majority are the self‐propelled type. The importance of the pull‐towed barges is declining quickly, whereas the push‐towed barges are on the upswing.

3) The relative importance of inland shipping in comparison with rail transport is far from uniform. In The Netherlands inland shipping is dominant. On the other hand, in France, this mode of transport has only 30 percent of the total number of tons transported by inland shipping and railways together.

4) May the relative importance defer, there is a strong resemblance between the types of goods that are transported via the waterways with crude and manufactured minerals as well as building materials ranking high. In general, inland shipping is primarily involved in the transport of basic products and is of vital importance to the functioning of the West‐European economy.

5) The rather complicated legal regime of the waterways in Western Europe is certainly not the only reason why the integration in the transportation sector of the European Communities hardly moves on.

A fundamental discussion about the basic conceptions of the transport policy in the Common Market is unavoidable before real progress can be made. The entrance of the United Kingdom into the European Community may give an opening on this point.

6) Life goes on, with or without transport‐integration. Inland shipping moves forward too, paying for the use of infrastructure or not.

The general trends in transport support the expectation that the relative importance of inland shipping will increase in the coming decades. The increase in size of shipments and transport distances works in favour of this mode of transport. Besides this, inland shipping still has many possibilities to improve its productivity.

7) The future of inland shipping will be found in bulk transport and the transport of general cargo that has a volume per destination that goes far beyond the quantities for which the container or comparable types of transport units are better suited.     

Extracting driving characteristics from heavy goods vehicle tachograph charts

European Union regulations require haulage companies of member states like the UK to keep records of their drivers’ hours of work. All heavy goods vehicles (HGV's) over 7.5 tonnes are fitted with tachographs which record a driver's operating activities (periods of driving, other work and rest). These records are etched onto a laminated chart by various styli, one of which records the vehicle's speed. This paper describes the development and testing of a new technique for extracting individual driving characteristics from the speed trace of an HGV tachograph chart to calculate four parameters: distance travelled, average speed, time travelled and speed variability.

The average speed, time travelled and speed variability were analysed statistically using one‐way analysis of variance tests. Speed variability was found to be particularly useful for identifying differences between individual driver's behaviour. Once differences in behaviours can be identified it may be possible to link certain driving habits to factors such as component wear, accident rates and excessive fuel usage.     

Patterns of urbanization and energy requirements: recent regulation changes and simulation studies concerning American urban areas

In recent years, the world economy has become more integrated internationally and container transportation has become increasingly more important as the proportion of all trade using containers is continuously growing. In order to adapt to the increasing containerization trend, it is essential to plan and construct adequate ports and facilities to cope with this development.

Based on the analysis of factors influencing container movements, this paper illustrates the logical relationships for a distribution model, which has been used to predict the distribution of containers among the three main Seaports near Shenzhen and Hong Kong. A fuzzy number‐based distribution model is outlined in the paper. The paper illustrates the main influencing factors and their logical relationships and proposes a primary distribution model where the attractiveness of each port has been calibrated. The results show that the Port of Hong Kong is significantly more attractive than the other two ports modelled and is likely to continue to be so in the future.