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In order to implement the objective, necessary infrastructure was established
to provide fast, stable and uninterrupted transmission of data from hundreds of
detectors and cameras at intersections. For the infrastructure, more than 100 km of
telecommunication underground ducts were built, and 300 km of cables were installed.
Within the active network, 15 distribution switches as well as 148 access switches were
installed (together with almost 300 expansion modules), which constitute a transmission
network for ITS devices.
Figure 7.6 Passenger information generated by ITS [7]
The basic task of Dynamic Passenger Information System is to provide passengers
with information on estimated departure time of the vehicle operating a particular
line from selected bus/tram stop (see Figure 7.6). The information on the departure
time is given by means of information boards. Apart from informing the passengers
on the name of the stop, the line number, estimated or scheduled departure time, the
subsystem allows for the provision of organisational messages to passengers (information
on detours, difficulties in traffic, ticket prices, etc.).
The primary function of information system for drivers is to provide road users
with reliable comparative information on traffic conditions on two alternative routes
between fixed points in the area of Wroclaw (see Figure 7.7). The measure for traffic
conditions is the estimated travel time by alternative routes between chosen points,
which is intended to help the road users choose the route. Drivers have access to 13
boards with variable message signs located at key points in the city. In order to conduct
measurements, 51 license plate recognition cameras ARTR were installed as well as 12
Bluetooth readers supporting the measurements.
Data repository system is an organised place of storing data from ITS system,
most of which is dedicated to be presented in the form of reports and to be processed as
analytical data. The very ITS data repository was designed in a domain-specific manner,
which means that groups of tables were created which contain specialist data from
specified extent (e.g. data on traffic, data on exclusions from traffic).