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arXiv · 1511.08303

Engineering Oracles for Time-Dependent Road Networks

Spyros Kontogiannis·George Michalopoulos·Georgia Papastavrou·Andreas Paraskevopoulos·Dorothea Wagner·Christos Zaroliagis
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Abstract

We implement and experimentally evaluate landmark-based oracles for min-cost paths in large-scale time-dependent road networks. We exploit parallelism and lossless compression, combined with a novel travel-time approximation technique, to severely reduce preprocessing space and time. We significantly improve the FLAT oracle, improving the previous query time by $30\%$ and doubling the Dijkstra-rank speedup. We also implement and experimentally evaluate a novel oracle (HORN), based on a landmark hierarchy, achieving even better performance wrt to FLAT.

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Spyros Kontogiannis, George Michalopoulos, Georgia Papastavrou, Andreas Paraskevopoulos, Dorothea Wagner, Christos Zaroliagis. 2015-11-26. Engineering Oracles for Time-Dependent Road Networks. https://arxiv.org/abs/1511.08303

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