1. Topic

2. Introduction

Accessibility of urban areas is mostly reduced by traffic congestion. Traffic congestion causes hot spot air pollution. Traffic management is necessary for improving accessibility as well as for improving air quality. An issue to solve is the fact that there is the possibility to have a difference between the road capacity calculated from a traffic science point of view and the road capacity based on air quality standards.

Reducing the amount of car traffic can be done by stimulating people to use bicycles and public transport. This modal shift can be achieved by pricing schemes, giving incentives or information. This measures also can be used to reduce traffic congestion.

Dividing and dosing traffic is done by tuning traffic lights. It gives the possibility to choose where cars can ride on and where they have to wait.

3. Discussion

The demand to use cars is, in general, not in line with the capacity of the road system, specifically in certain peak periods. Adding more infrastructure will lead to more cars. So there always will be traffic congestion somewhere.

For the accessibility of urban areas and the urban environment it is important that bicycle traffic and public transport experience no delays caused by congestion traffic. Car drivers should be aware of this and they should be informed about expected delays before they start their trip, at home. In this regard, they can choose another means of transport, another destination, another time to travel or another route.

When they have chosen to use their car, they should be informed about available routs, free of congestion, best speed (green wave principle) and available parking places at their destination.

With these specific aims, traffic management systems are presently available with the following specifications:

Information for car drivers:

· Trip planning (pre-trip): e.g. for modal choice;

· Real time or (on-trip information on routes and traffic: e.g. for real-time infrastructures (roads and parking areas) condition;

· Navigation and driving assistance (on-trip): e.g. for path choice and

· Personal communication (on-trip): e.g. for emergency call.

For the management of a traffic network:

· Global network traffic control: e.g. traffic forecasts;

· Local areas traffic control: e.g. exclusive use of lanes or tunnels;

· Parking management: e.g. parking places availability;

· Environment conditions monitoring: e.g. pollution levels;

· Road conditions monitoring: e.g. state of the running surfaces;

· Special events forecasts: e.g. extraordinary high flows;

· Safety and security: e.g. emergency call management;

· Infrastructure maintenance: e.g. maintenance actions management and planning;

· Road pricing: e.g. fares calculation and

· Enforcement: e.g. restricted areas violating vehicles identification.

As stated before, the current transport system will know traffic jams at certain moments and times.

The main question is where to accept congestion and queues. Nobody is interested in having them “in their back yards”. A current trend is Highway authorities try to avoid traffic jams on the highways by limiting access to the highways and separating through traffic from regional traffic (e.g. stimulate and organise the use of parallel ways). This brings the problems to a lower governance level, in particular cities and municipalities. So around the approach roads should be some buffer space for dosing incoming traffic.

Companies and travellers compare the accessibility of cities. Companies put pressure on cities to improve the car accessibility. So the car accessibility of a city cannot be much worse than other cities. Also the parking prices are limited by the competition position of the city.

4. Recommendation / Conclusion

· The amount of parking places must be in balance with the infrastructure. Too many and too little parking places lead to stagnating traffic.

· Introduce paid parking with higher prices in the middle of the town.

· Benefit cycling and public transport at traffic lights.

· Inform about traffic jams (radio/sms), free ways (radio/sms), best speed (signs) and available parking places (signs).

· Try to find suitable places for stagnating traffic. The delay has to be predictable at the moment a car joins at the back and inform about better alternatives. It can be the right place for a transfer station.

· Determine the road capacity based on air quality and noise standards and use traffic lights to dosage the traffic.

· The main barriers to be faced for the full applicability of both families of systems: car driver assistance and traffic management systems may be summarised in:

a. Partial correspondence between systems performances and transport management requirements (mainly due to the import of technologies from other sectors);

b. General lack of information on performances of the technological systems and their development state;

c. Critical mass problem: duality between absence of demand and absence of offer;

d. Partial correspondence between costs supporter and benefits acquirer;

e. Complexity of technological and organisational integration of different systems and technologies;

f. Fragmentation of public decision centres;

g. Inadequacy of existing laws and regulations;

h. Potentiality of reduction of the personal freedom and privacy.

5. Examples / Further Reading

· Main related projects within the EUREKA European Research Programme (since 1985): DEMETER, EUROPOLIS and PROMETHEUS.

· Main related projects within the DRIVE I European Research Programme (1988-1991): ASTERIX, FLEET, IMPACT, MONICA, ODIN, SECFO, SMILER, TARDIS.

· Main related projects within the DRIVE II European Research Programme (since 1992): ACCEPT, ADEPT, ADS, ARIADNE, ATT-ALERT, CASH, CITIES, COMBICOM, DETER, DYNA, EMMIS, EUROCOR, GAUDI (including test sites in Barcelona, Bologna, Dublin, Marseille and Trondheim), GEMINI, HERMES, HOPES, IFMS, KITS, LLAMD, MARTA, MELYSSA, METAFORA, MIRO, PLEIADES, PROMISE, QUARTET (including test sites in Athens, Birmingham, Goteborg, Stuttgart, Toulouse and Turin), QUO VADIS, ROSES, SCOPE, SOCRATES and TESCO.

· Related Project within the THERMIE European Research Programme: ANTARES.

· Related Project within the VALUE European Research Programme: FIESTA.

· Main related projects within the European Research 4^th Framework Programme: ASSIST, ATHOS, CARPLUS, CHAUFFEUR, CLEOPATRA, CONCERT, CONVERGE, COSMOS, CROMATICA, DACCORD, EUROSCOPE, FAR AWAY, FORCE, HANNIBAL, ICARE, INFOTEN/INTERMATRIX, MANTEA, MARCO, MORANE, QUARTET Plus, ROSIN, SAMPO, SAVE, SHIDDESS, SURFF, UDC.

· Main related USA Research programmes and projects: MOBILITY 2000, PATH, PATHFINDER and SMART CORRIDOR.

· Main related Japanese Research programmes and projects: AMTICS, ATICS, CACS, RACS.

Further Examples:

6. Additional Documents / Web Links

· ATC Bologna – Sistemi di supporto alla pianificazione del trasporto pubblico – Salone del traffico e della mobilità, Bologna, 10-13.02.1994.

· Bijesterbos J.W.M., Zijderhand F. – SOCRATES: a dynamic car navigation driver information and fleet management system – Philips Journal of Research, 02.1995

· CORD Project V2056 – Recommended Definitions of Transport Telematics Functions and Subfunctions – Deliverable D004, part 3, 1994.

· ECMT-ERTICO – Road Transport Informatics. Institutional and Legal Issues – ECMT, 1995.

· European Commission – Transport Telematics in Cities. Experience gained from urban pilot projects of the Transport Telematics sub-programme under the 3^rd Framework Programme (1992-1994), 1995.

· Frost & Sullivan – U.S. Intelligent transportation Systems (ITS) Market – First Update, 1995.

· Guerci C.M. (a cura di) – Telecomunicazioni e informatica per i trasporti. Tecnologia e mercato al 2005. ISFORT, Il Mulino, 1996.

· Ministero dei Lavori Pubblici (coordinamento) – Piano Nazionale Telematica 1996-2000, 1995.

Other examples in EU Projects:

· CENTAUR: Toulouse (France), Leipzig (Germany), Dublin (Ireland), Naples (Italy), Barcelona and Las Palmas (Spain) and Bristol (UK).

· ENTIRE: Caen (France) and Venice (Italy).

· JUPITER-2: Gent (Belgium), Aalborg (Denmark), Heidelberg (Germany), Bilbao (Spain) and Merseyside (United Kingdom)

· NGVeurope: Eslov (Denmark), Dublin (Ireland) and Gothenburg (Sweden).

· SAGITTAIRE: Bruges and Leuven (Belgium), Besancon (France), Savona (Italy), Stavanger (Norway) and Sintra (Portugal).

· OSCAR: city reports (2003)

· References in the Netherlands: http://www.vrom.nl and http://www. infomil.nl

Last Updated

25th January 2005