# Hierarchical Time-Dependent Oracles

@inproceedings{Kontogiannis2016HierarchicalTO, title={Hierarchical Time-Dependent Oracles}, author={Spyros C. Kontogiannis and Dorothea Wagner and Christos D. Zaroliagis}, booktitle={ISAAC}, year={2016} }

We study networks obeying time-dependent min-cost path metrics, and present novel oracles for them which provably achieve two unique features: (i) subquadratic preprocessing time and space, independent of the metric’s amount of disconcavity; (ii) sublinear query time, in either the network size or the actual Dijkstra-Rank of the query at hand.

## 6 Citations

### An Axiomatic Approach to Time-Dependent Shortest Path Oracles

- Computer ScienceAlgorithmica
- 2022

This work presents an axiomatic approach which shows that for directed networks that satisfy certain properties the authors can provide time-dependent distance oracles that provably exhibit subquadratic preprocessing time and space (independent of the metric’s amount of disconcavity).

### Time-Dependent Alternative Route Planning: Theory and Practice

- Computer ScienceAlgorithms
- 2021

A novel query algorithm, called Time-Dependent Alternative Graph (TDAG), that exploits the outcome of a time-consuming preprocessing phase to create a manageable amount of travel-time metadata, in order to provide answers for arbitrary alternative-routes queries, in only a few milliseconds for continental-size instances.

### Time-Dependent Alternative Route Planning

- Computer ScienceATMOS
- 2020

This work presents a new method for computing a set of alternative origin-to-destination routes in road networks with an underlying time-dependent metric that is characterized by minimum route overlap, small stretch factor, small size and low complexity.

### A Cloud-Based Time-Dependent Routing Service

- Computer ScienceALGOCLOUD
- 2016

This work describes the architecture of the time-dependent routing engine, consisting of a core routing module along with the so-called urban-traffic knowledge base, which creates, maintains and stores historic traffic data, as well as live traffic updates such as road blockages or unforeseen congestion.

### Algorithms for Cloud-Based Smart Mobility

- Computer ScienceALGOCLOUD
- 2018

This work reviews some recent innovative algorithmic approaches that contributed decisively in the development of efficient and effective cloud-based systems for smart mobility in urban environments.

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