Finding Fastest Paths on A Road Network with Speed Patterns
Evangelos Kanoulas, Yang Du, Tian Xia and Donghui Zhang
Abstract
This paper proposes and solves the Time-Interval All Fastest Path
(allFP) query. Given a user-defined leaving or arrival time
interval I, a source node s and an end node e,
allFP asks for a set of all fastest paths from s to e,
one for each sub-interval of I. Note that the query algorithm
should find a partitioning of I into sub-intervals. Existing
methods can only be used to solve a very special case of the problem,
when the leaving time is a single time instant. A straightforward
solution to the allFP query is to run existing methods many times,
once for every time instant in I. This paper proposes a
solution based on novel extensions to the A* algorithm. Instead of
expanding the network many times, we expand once. The travel time on a
path is kept as a function of leaving time. Methods to combine
travel-time functions are provided to expand a path. A novel
lower-bound estimator for travel time is proposed. PerUnsaved Document
1formance results reveal that our method is more efficient and more
accurate than the discrete-time approach.