Shortest-path and minimum-delay algorithms in networks with time-dependent edge-length
Journal of the ACM (JACM)
Fast Computation of Point-to-Point Paths on Time-Dependent Road Networks
COCOA 2008 Proceedings of the 2nd international conference on Combinatorial Optimization and Applications
Engineering Route Planning Algorithms
Algorithmics of Large and Complex Networks
Car or Public Transport--Two Worlds
Efficient Algorithms
Efficient Timetable Information in the Presence of Delays
Robust and Online Large-Scale Optimization
Fast paths in large-scale dynamic road networks
Computational Optimization and Applications
Landmark-based routing in dynamic graphs
WEA'07 Proceedings of the 6th international conference on Experimental algorithms
WEA'07 Proceedings of the 6th international conference on Experimental algorithms
Contraction hierarchies: faster and simpler hierarchical routing in road networks
WEA'08 Proceedings of the 7th international conference on Experimental algorithms
Highway dimension, shortest paths, and provably efficient algorithms
SODA '10 Proceedings of the twenty-first annual ACM-SIAM symposium on Discrete Algorithms
An empirical comparison of some multiobjective graph search algorithms
KI'10 Proceedings of the 33rd annual German conference on Advances in artificial intelligence
Passenger flow-oriented train disposition
ESA'11 Proceedings of the 19th European conference on Algorithms
Fully dynamic maintenance of arc-flags in road networks
SEA'12 Proceedings of the 11th international conference on Experimental Algorithms
Context-aware modelling of continuous location-dependent queries in indoor environments
Journal of Ambient Intelligence and Smart Environments - Context Awareness
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We introduce two new speed-up techniques for time-dependent point-to-point shortest path problems with fully-dynamic updates in a multi-criteria setting. Our first technique, called SUBITO, is based on a specific substructure property of time-dependent paths which can be lower bounded by their minimal possible travel time. It requires no preprocessing, and the bounds can be computed on-the-fly for each query. We also introduce k-flags, an extension of arc flags, which assigns to each arc one of k levels for each region of a vertex partition. Intuitively, the higher the level of an arc for a certain destination, the larger the detour with respect to travel time. k-flags allow us to handle dynamic changes without additional time-consuming preprocessing. In an extensive computational study using the train network of Germany we analyze these and other speed-up techniques with respect to their robustness under high and realistic update rates. We show that speed-up factors are conserved under different scenarios, namely a typical day of operation, distributed delays after “heavy snowfall”, and a major disruption at a single station. In our experiments, k-flags combined with SUBITO have led to the largest speed-up factors, but only marginally better than SUBITO alone. These observations can be explained by studying the distribution of k-flags. It turns out that only a small fraction of arcs can be excluded if one wants to guarantee exact Pareto-optimal point-to-point queries.