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Technical Report: DCC-2001-4
Modelling Optimal Location of Traffic
Counting Points at Urban
Intersections in CLP(FD)
Ana Paula Tomás
DCC-FC & LIACC, Universidade do Porto
R. do Campo Alegre 823, 4150-180 Porto, Portugal
Phone: 351 22 6078830, Fax: 351 22 6003654
E-mail: apt@ncc.up.pt
May 2001
Abstract
Traffic studies for network planning,
design, management and control, require
origin-destination demand data whose acquisition is difficult and
expensive.
Important, but often insufficient, data is
collected
by counting
vehicles passing
at specific points of the traffic network.
An application of Constraint Programming
for finding the minimum number and location of
count-posts at urban roundabouts so as to
obtain origin-destination data at minimum cost is given.
By finding interesting mathematical properties,
we were able
to model this problem as a constraint
satisfaction problem in
finite domains.
Prototype implementations in ECLiPSe and clp(fd) for SICStus Prolog
are discussed.
This paper appears as a complement to
a previous work, which is described in the Internal Report DCC-2001-2,
for which programs were implemented (in C) to
perform an exhaustive case analysis of hypothetical roundabouts,
seeking for possible patterns for the optimal solutions for some
given cost functions. It is motivated by the observation that
the cost criteria should be more flexible to
encompass specific features of the particular roundabout in
study.
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