In order to improve air
quality it is necessary to control the quantity, speed and flow of traffic
moving through an urban area. Traffic signals have been used for many years for
controlling traffic flow at junctions but in more recent years integrated
systems have been developed to link several junctions together to make them
work in harmony and prevent congestion. This also has the effect of reducing
pollution from standing traffic. During periods of poor air quality it may also
be possible to use signals to hold back traffic queues away from pinch points
to allow for congestion to clear, especially if the traffic is held in a more
open area where pollutants are able to disperse more easily.
To modify the way
people behave it is necessary to provide them with information. Encouraging
drivers to use public transport because of poor air quality or congestion ahead
may be effective, especially when located next to large car parks with good
public transport links, e.g. Park and Ride. If the national transport
regulations allow, it may be effective to encourage drivers to switch off their
engines while waiting in traffic queues, for example at train crossings or
swinging river bridges. Information on the number or parking spaces which are
available in car parks can prevent needless searching from one car park to
another, especially at times when the central car parks are full.
The use of transponders
within vehicles can also be of value. They are able to provide the location of
buses or other forms of public transport which can then accurately display the
arrival time at bus stops. This is of benefit to the public and so may
encourage them to use public transport rather than their own. Some
municipalities may benefit from restricting access to general traffic to
certain areas but allow public transport and emergency vehicles access through
a light controlled or physical barrier which is activated by the transponder in
the vehicle. If a municipality decides to charge for access to some parts of
the city it may be more efficient to have "smart cards" in the
vehicle which effectively "pay" for entry without having to stop at a
physical barrier, which in itself would add to congestion.
The application of Telematics requires resources both for acquiring the basic
data (network topology, flows, accidents, emissions, etc.), their elaboration
(interpretation of phenomena by models) and communication to the driver (information,
assistance, navigation, regulation and control) or, in case of full automation,
to the automatic driving system (self regulation on-board, exchange of
information among the vehicles, external integrated control).
The present state of the applied technology include for the passengers
the possibility of:
- Pre-information of car drivers
on traffic condition on the various alternative paths to the destination,
continuous assistance during the movement with possibility to book and
acquire additional services;
Pre-information of public transport user about the arrivals
of the vehicle and the amount of passengers on board. |