13 Tracking of Moving Objects with Accuracy Guarantees
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• Use of Acceleration Profiles. An acceleration profile divides a route into intervals
with constant acceleration and thus enables quite accurate modeling of the speed
of an object as it travels along a route. The idea underlying the use of acceleration
profiles is to reduce the number of updates incurred by speed variations.
Experimental performance studies using real GPS logs and corresponding real
road networks representation illustrate the following observations:
• It is possible to improve the performance of segment-based tracking by automatic resegmentation of the underlying road network representation. Experiments with three resegmentation algorithms demonstrate this and offers insight
into which types of modification are most effective in reducing the number of
updates.
• It is indeed attractive to use precomputed routes for the moving objects in
segment-based tracking, instead of using segments from the road network representation. The GPS logs used confirm conventional wisdom that mobile users
are creatures of habit (or efficiency) that frequently use the same routes through
the road network to reach their destinations.
• The GPS data used also reveal distinctive speed patterns for some routes and
mobile users. The experimental results show that the use of acceleration profiles
is capable of increasing the performance of segment-based tracking.
13.8 Further Reading
We proceed to offer an overview of related developments in the commercial and
academic arenas. We first offer an overview of 26 tracking-related products and services that we believe are representative of the current commercial state of the art. We
then provide an overview of related works within the academic community that may
impact future commercial offerings.
13.8.1 Commercially Available Products and Services
Table 13.1 summarizes pertinent properties of what we believe is a representative
range of commercially available tracking solutions. The table captures properties of
26 solutions provided by 23 companies. The information that went into the creation
of the table was obtained via the Internet during January 2006.
The first column lists company names, and the second lists product names. Starting from the third, each column concerns one product property, and a check mark
in a cell indicates that the product in the row of the cell possesses the property corresponding to the column of the cell. The absence of a check mark indicates the
opposite.
Columns GPS, Cell, and WAAS concern the means of positioning supported, with
Cell denoting cellular network-based positioning and WAAS denoting the wide area
augmentation system that is based on GPS, but offers higher accuracy than GPS by
305
• Use of Acceleration Profiles. An acceleration profile divides a route into intervals
with constant acceleration and thus enables quite accurate modeling of the speed
of an object as it travels along a route. The idea underlying the use of acceleration
profiles is to reduce the number of updates incurred by speed variations.
Experimental performance studies using real GPS logs and corresponding real
road networks representation illustrate the following observations:
• It is possible to improve the performance of segment-based tracking by automatic resegmentation of the underlying road network representation. Experiments with three resegmentation algorithms demonstrate this and offers insight
into which types of modification are most effective in reducing the number of
updates.
• It is indeed attractive to use precomputed routes for the moving objects in
segment-based tracking, instead of using segments from the road network representation. The GPS logs used confirm conventional wisdom that mobile users
are creatures of habit (or efficiency) that frequently use the same routes through
the road network to reach their destinations.
• The GPS data used also reveal distinctive speed patterns for some routes and
mobile users. The experimental results show that the use of acceleration profiles
is capable of increasing the performance of segment-based tracking.
13.8 Further Reading
We proceed to offer an overview of related developments in the commercial and
academic arenas. We first offer an overview of 26 tracking-related products and services that we believe are representative of the current commercial state of the art. We
then provide an overview of related works within the academic community that may
impact future commercial offerings.
13.8.1 Commercially Available Products and Services
Table 13.1 summarizes pertinent properties of what we believe is a representative
range of commercially available tracking solutions. The table captures properties of
26 solutions provided by 23 companies. The information that went into the creation
of the table was obtained via the Internet during January 2006.
The first column lists company names, and the second lists product names. Starting from the third, each column concerns one product property, and a check mark
in a cell indicates that the product in the row of the cell possesses the property corresponding to the column of the cell. The absence of a check mark indicates the
opposite.
Columns GPS, Cell, and WAAS concern the means of positioning supported, with
Cell denoting cellular network-based positioning and WAAS denoting the wide area
augmentation system that is based on GPS, but offers higher accuracy than GPS by