For large study areas or dense traffic networks
simulation is computationally challenging. TRAQS
therefore provides the key model components in
both a sequential and a parallel processing variant.
The parallel implementation allows simulation runs
to be distributed over several processors (even over
a fast LAN) as application size requires. TRAQS
supports scaling further by separating user interface
and simulation models: the model server can be
accessed from a light-weight client with average
With its unique combination of simulation models
TRAQS can incorporate a diverse range of data
sources into an overall picture of pollution levels:
- basic geographic data for the study area, e.g.
elevation model, administrative divisions, land-use,
- detailed representation of the road traffic network
with a rich set of attributes supporting detailed
traffic flow simulation
- traffic demand expressed as a baseline O-D matrix
and additional event-related matrices
- models for a range of traffic management measures
on different time-scales
- meteorological observations, taken from historical
records, from current measurements or from
- emission inventories for several non-traffic related
sources, e.g. household, industry, and for non-
moving traffic not captured in the simulation.
A major strength of TRAQS is the model support for
traffic management options, including route
guidance, speed restrictions, limited access, new
roads, and temporal / spatial shifts in demand. It
therefore lends itself not only to assess the environ-
mental impact, but also to develop transportation
strategies for the sustainable cities of tomorrow.
The main system components are integrated with an
interactive and graphical user interface designed for
users with little or no computer experience.
Online help guides the user through the complete
life-cycle of a TRAQS application project.
TRAQS is developed for PCs running Windows NT.
The machine hosting the simulation models should
be equipped with a fast Pentium-II processor, at least
128 MB RAM, and a minimum of 2 GB disk space,
although actual requirements vary with the amount
of model input data, e.g. historical time series of
The user interface (client) can either run on
the same machines as the
models or separately on a Windows NT PC with at
least 64 MB RAM. The integrated GIS system
requires a graphics resolution of at least 1280 x
1024 with 256 simultaneous colours.
Support for Unix configurations is available on