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Hengfeng Li, Lars Kulik, Kotagiri Ramamohanarao Department of Computing and Information SystemsThe University of [email protected]
Robust Inferences of Travel Paths from GPS Trajectories
PROBLEM
METHOD
CASE STUDY
CONTRIBUTIONS
Problem: How to infer a travel path on the road network from a GPS trace under noisy conditions?
We propose a spatial-linear clustering algorithm to group noisy GPS points:
Proposing an efficient cluster-based mapping algorithm; Conducting extensive experiments on both synthetic and real data sets; Demonstrating a case study by applying resulting travel paths for traffic flow monitoring.
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GPS Point
Road SegmentTravel Path (Ground Truth)Linear Cluster
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Projection Point
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(a) A GPS trace (1Hz sampling rate)
(b) A possible solution (c) A better solution
Our Method:
(a) employ spatial-linear clustering to group GPS points; (b) derive and amalgamate sub-paths of point clusters.
Noisy PointAnchor Point
GPS Point
Road Segment
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(a) (b)An example to build groups of GPS points by increasing an oriented bounding rectangle with error-bounded distance.
Anchor PointRoad Segment
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An example of generating possible routes bounded by the spatial-linear cluster.
(a) (b)
We conduct a case study to analyze the impact of map matching for the estimation of traffic flow of a large area.
(a) Travel distance and travel time (b) Actual overall traffic
(c) Ground truth (d) OBR-HMM (e) HMM
(f) Ground truth (g) OBR-HMM (h) HMM
(i) Ground truth (j) OBR-HMM (k) HMM
OBR-HMM: Our method HMM: Competing algorithm
RELATED PUBLICATIONSHengfeng Li, Lars Kulik, Kotagiri Ramamohanara: Robust Inferences of Travel Paths from GPS Trajectories. Submitted to International Journal of Geographical Information Science (under review). Hengfeng Li, Lars Kulik, Kotagiri Ramamohanara: Spatio-Temporal Trajectory Simplification for Inferring Travel Paths. In proceedings of the 22nd ACM SIGSPATIAL International Conference on Advances in Geographic Information Systems (ACM SIGSPATIAL 2014), pages 63-72.
We derive travel paths for point clusters and combine them into a single complete path:
Poster theme adopted from TikZposter
