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LAMI 1. User Oriented Trajectory Similarity Search 2. Calibration-free Localization using Relative Distance Estimations 3. From GPS Traces to a Routable Road Map
Radu Mariescu-Istodor10.2.2014
Similarity Search
Naive solution is to compare Every pair of points (108)From reference route and Every route in DB (105)
Average route length ~1000 points.
108 haversines ~ 30 minutes
Limiting the space
R-tree indexed points => easy to conduct range checks
Naive solution is to compare Every pair of points (108)From reference route and Every route in DB (105)
the routes that have at least one point in one of the squares
Improve speed of HCSSHeaviest Grouped Subsequence
HCSS ≤ HGSS
1. HGSS = 4922. HGSS = 4523. HGSS = 4124. HGSS = 301……………….
HCSS ?
How it works?
Cell1=50%Cell2=80%Cell3=60%
Cell1=80%Cell3=20%Cell5=30%Cell6=20%
Common Cells = 2Uncommon Cells = 3Spearman = ?
Feature :
(Experimentally deduced)
Regression Formula(Experimentally deduced)
Fitted from GPS phones
Features ={Common, Uncommon, Spearman}
Merging nearby trajectories
Gravity Spring
Resultant force applied in small iterations until change insignificant