Vol 3 No 1 (2003)
2003-08-01
Vol 3 No 1 (2003)
2003-08-01
Articles
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Many Intelligent Transport Systems (ITS) that are now under intensive investigation have been designed or assessed with a particular target consumer group in mind. In order for these (and many other) systems to be successfully used around the globe however, some appreciation will be necessary of how behaviours, and hence uses and impacts, may change between different sites and between different countries. This article reports on an instrumented vehicle study designed to assess differences in Motorway driving behaviour between three sites, one in the U.K., one in France and one in Germany. Substantial differences were found between typical car-following headways and time to collisions observed at the sites. The experiment also confirmed that many people drive well below the current recommended safe following distances. It has not been possible through this study to determine why the differences exist between the sites, nor whether they are country specific. However, the findings are important in establishing that significant differences do exist. These differences could impact on the effectiveness of roadside telematics systems as well as for the design of in-vehicle Advanced Vehicle Control and Safety Systems.
Many Intelligent Transport Systems (ITS) that are now under intensive investigation have been designed or assessed with a particular target consumer group in mind. In order for these (and many other) systems to be successfully used around the globe however, some appreciation will be necessary of how behaviours, and hence uses and impacts, may change between different sites and between different countries. This article reports on an instrumented vehicle study designed to assess differences in Motorway driving behaviour between three sites, one in the U.K., one in France and one in Germany. Substantial differences were found between typical car-following headways and time to collisions observed at the sites. The experiment also confirmed that many people drive well below the current recommended safe following distances. It has not been possible through this study to determine why the differences exist between the sites, nor whether they are country specific. However, the...
Many Intelligent Transport Systems (ITS) that are now under intensive investigation have been designed or assessed with a particular target consumer group in mind. In order for these (and many other) systems to be successfully used around the globe however, some appreciation will be necessary...
G. R. Marsden, M. McDonald, M. Brackstone -
To support operators in Regional Traffic Management Centers in their task to efficiently and safely manage traffic flows on the motorway and urban networks, a decision support system is being developed. An essential function of this system is its ability to predict the effects of a large number of candidate control scenarios, given the recurrent and non-recurrent conditions in the network. This article proposes such a prediction system referred to as BSES (Boss Scenario Evaluation System), which can evaluate control scenarios in real time, predicting their effects in terms of various measures of effectiveness, such as total travel times, vehicle loss times, average speeds, fuel consumption, etc. The main characteristics of the system are l) that it is case- based, i.e. it uses either synthetic or real-life examples of the effect of control scenarios under different circumstances; 2) that is determines the similarity of the current situation to different examples in the case-base using fuzzy logic, and 3) that it is agent-based, meaning that it predicts the effects of the different measures for small subnetworks and combines these predictions afterwards. In the article, synthetic data is used to set-up the case base. The test results described in the article illustrate the workings of the system, and shows that the system can provide the operator with real-time predictions. Furthermore, the predictions of the system are in comparable to the predictions from the simulation model used to fill the case-base, showing that the method is applicable to generalize the - in this case synthetic - data it uses.
To support operators in Regional Traffic Management Centers in their task to efficiently and safely manage traffic flows on the motorway and urban networks, a decision support system is being developed. An essential function of this system is its ability to predict the effects of a large number of candidate control scenarios, given the recurrent and non-recurrent conditions in the network. This article proposes such a prediction system referred to as BSES (Boss Scenario Evaluation System), which can evaluate control scenarios in real time, predicting their effects in terms of various measures of effectiveness, such as total travel times, vehicle loss times, average speeds, fuel consumption, etc. The main characteristics of the system are l) that it is case- based, i.e. it uses either synthetic or real-life examples of the effect of control scenarios under different circumstances; 2) that is determines the similarity of the current situation to...
To support operators in Regional Traffic Management Centers in their task to efficiently and safely manage traffic flows on the motorway and urban networks, a decision support system is being developed. An essential function of this system is its ability to predict the effects of a large...
Serge P. Hoogendoorn, Bart De Schutter, Henk Schuurman -
In this paper the integrated traffic control and traffic assignment problem is studied. This problem can be considered as a non-cooperative game in which the traffic authority, that controls the traffic signals, and the road users are the players, who use their own strategy and seek their own optimum. The game theoretical formulation leads to several different control strategies in which users’ reactions to traffic control decisions are taken into account. Users’ reactions can be the choice of route, departure time or even mode, but here only route choice is considered.
In this paper some of these control strategies for traffic signal control are described: Webster control, Smith’s P , Anticipatory Control and System Optimum Control. The first two control strategies are well known and described in the literature. The anticipatory control strategy can be formulated as a bi-level optimisation problem and this problem is solved using genetic algorithms. Also the system optimum solution can be found using genetic algorithms, simultaneously optimising route flows and green times.
In the paper the assignment method, together with the traffic model, is formulated. In the assignment several user classes, each with its own perception of route costs, are defined and taken into account. For several simple example networks the traffic control methods are tested and it is shown that taking route choice into account is beneficial to the network performance. Further research will focus on the improvement of the traffic model used in the control optimisation, realistic networks and the problem of departure time choice.
In this paper the integrated traffic control and traffic assignment problem is studied. This problem can be considered as a non-cooperative game in which the traffic authority, that controls the traffic signals, and the road users are the players, who use their own strategy and seek their own optimum. The game theoretical formulation leads to several different control strategies in which users’ reactions to traffic control decisions are taken into account. Users’ reactions can be the choice of route, departure time or even mode, but here only route choice is considered.
In this paper some of these control strategies for traffic signal control are described: Webster control, Smith’s P , Anticipatory Control and System Optimum Control. The first two control strategies are well known and described in the literature. The anticipatory control strategy can be formulated as a bi-level optimisation problem and this problem is solved using genetic algorithms....
In this paper the integrated traffic control and traffic assignment problem is studied. This problem can be considered as a non-cooperative game in which the traffic authority, that controls the traffic signals, and the road users are the players, who use their own strategy and seek their...
Henk Taale, Henk van Zuylen -
This book presents the Proceedings of the 15th International Symposium on Transportation and Traffic Theory (ISTTT), held at the University of South Australia in July 2002. The ISTTT is one of the most important gatherings for transportation and traffic theoreticians. Its main purpose is to share advances in the scientific aspects of transportation and traffic phenomena. A renowned International Committee and the plurality of excellent contributors, makes this book a valuable tool for the scientific and professional world in the transportation and traffic arena.
This book presents the Proceedings of the 15th International Symposium on Transportation and Traffic Theory (ISTTT), held at the University of South Australia in July 2002. The ISTTT is one of the most important gatherings for transportation and traffic theoreticians. Its main purpose is to share advances in the scientific aspects of transportation and traffic phenomena. A renowned International Committee and the plurality of excellent contributors, makes this book a valuable tool for the scientific and professional world in the transportation and traffic arena.
This book presents the Proceedings of the 15th International Symposium on Transportation and Traffic Theory (ISTTT), held at the University of South Australia in July 2002. The ISTTT is one of the most important gatherings for transportation and traffic theoreticians. Its main...
J. E. Coeymans -
To assess the design of walking infrastructure such as transfer stations, shopping malls, sport stadiums, etc., as well as to support planning of timetables for public transit, tools to aid the designer are needed. To this end, microscopic and macroscopic pedestrian flow models can and have been applied. To calibrate and validate such models, as well as to gain more insight into the characteristics of pedestrian flows under a variety of circumstances, very detailed pedestrian flow data are required. This is why Delft University of Technology has recently carried out experimental pedestrian flow research.
This paper describes the experimental design (determination of process variables, measurement set-up, etc.), the resulting microscopic pedestrian data, as well as some first results for the narrow bottleneck experiment. Both microscopic and macroscopic characteristics of pedestrian flows are presented. Interesting first results pertain to the way in which the narrow bottleneck is used under saturated flow conditions, and the use of the space (or rather, width) upstream of the bottleneck in case of congestion.
To assess the design of walking infrastructure such as transfer stations, shopping malls, sport stadiums, etc., as well as to support planning of timetables for public transit, tools to aid the designer are needed. To this end, microscopic and macroscopic pedestrian flow models can and have been applied. To calibrate and validate such models, as well as to gain more insight into the characteristics of pedestrian flows under a variety of circumstances, very detailed pedestrian flow data are required. This is why Delft University of Technology has recently carried out experimental pedestrian flow research.
This paper describes the experimental design (determination of process variables, measurement set-up, etc.), the resulting microscopic pedestrian data, as well as some first results for the narrow bottleneck experiment. Both microscopic and macroscopic characteristics of pedestrian flows are presented. Interesting first results pertain to the way in which the...
To assess the design of walking infrastructure such as transfer stations, shopping malls, sport stadiums, etc., as well as to support planning of timetables for public transit, tools to aid the designer are needed. To this end, microscopic and macroscopic pedestrian flow models can and...
Winnie Daamen, Serge P. Hoogendoorn -
Taking into account the new dimensions of port production that have become evident during the recent past, this paper tackles the issue of port reorganisation. In the light of the changes in the world economy and the new competitive environment, the paper focuses on the new structures of the port industry and the characteristics of the contemporary port product within a more general analytical framework of ‘Worlds of Production’. This conceptualisation suggests that neither the industrial model of mass production, nor any other model alone, can determine a single effective pattern of organisation of port production. Within the new reality, modern ports must provide a greater variety of services to port users than in the past. The diversity and complexity of the contemporary port product demand the application of multiple organisational transformations incorporating elements of different possible action frameworks. In this vein, the introduction of intra-port competition, the development of strategic or regional networks, and the reconsideration of the role of port authority turn to critical parameters of the essential restructuring.
Taking into account the new dimensions of port production that have become evident during the recent past, this paper tackles the issue of port reorganisation. In the light of the changes in the world economy and the new competitive environment, the paper focuses on the new structures of the port industry and the characteristics of the contemporary port product within a more general analytical framework of ‘Worlds of Production’. This conceptualisation suggests that neither the industrial model of mass production, nor any other model alone, can determine a single effective pattern of organisation of port production. Within the new reality, modern ports must provide a greater variety of services to port users than in the past. The diversity and complexity of the contemporary port product demand the application of multiple organisational transformations incorporating elements of different possible action frameworks. In this vein, the introduction of intra-port competition,...
Taking into account the new dimensions of port production that have become evident during the recent past, this paper tackles the issue of port reorganisation. In the light of the changes in the world economy and the new competitive environment, the paper focuses on the new structures of...
Constantinos I. Chlomoudis, Apostolos V. Karalis, Athanasios A. Pallis -
This new regular section looks at emerging issues with a definite pan-European focus and high significance for transport and/or infrastructure research. Three general inter-related themes will be examined in the new section − policy , practice and research . The connections between these themes will also be the focus of the section. Sometimes the section will primarily address one of these themes and at other times it will address two or all three of the themes. The policy theme will include recent developments in European transport policy and also recent developments in environmental, regional development and economic policy where there are specific implications for transport. The practice theme will include issues such as European benchmarking and pilot projects as well as recent developments in different transport industries across Europe (shipping, aviation and rail for example) and prospects for the future. The research theme will include topics such as recent developments in European research priorities and funding opportunities for transport and/or infrastructure research.
This new regular section looks at emerging issues with a definite pan-European focus and high significance for transport and/or infrastructure research. Three general inter-related themes will be examined in the new section − policy , practice and research . The connections between these themes will also be the focus of the section. Sometimes the section will primarily address one of these themes and at other times it will address two or all three of the themes. The policy theme will include recent developments in European transport policy and also recent developments in environmental, regional development and economic policy where there are specific implications for transport. The practice theme will include issues such as European benchmarking and pilot projects as well as recent developments in different transport industries across Europe (shipping, aviation and rail for example) and prospects for the future. The research...
This new regular section looks at emerging issues with a definite pan-European focus and high significance for transport and/or infrastructure research. Three general inter-related themes will be examined in the new section − policy , practice and research ....
Dominic Stead