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On Modularity Clustering
TLDR
The conjectured hardness of maximizing modularity both in the general case and with the restriction to cuts is proved and an Integer Linear Programming formulation is given.
Contraction Hierarchies: Faster and Simpler Hierarchical Routing in Road Networks
TLDR
CHs can be combined with many other route planning techniques, leading to improved performance for many-to-many routing, transit-node routing, goal-directed routing or mobile and dynamic scenarios, and a hierarchical query algorithm using bidirectional shortest-path search is obtained.
Route Planning in Transportation Networks
TLDR
It is shown that one can compute driving directions in milliseconds or less even at continental scale, and a variety of techniques provide different trade-offs between preprocessing effort, space requirements, and query time.
Hierarchical Hub Labelings for Shortest Paths
TLDR
This work studies hierarchical hub labelings for computing shortest paths to lead to faster preprocessing algorithms, making the labeling approach practical for a wider class of graphs.
Sketch-based Influence Maximization and Computation: Scaling up with Guarantees
TLDR
This work develops a novel sketch-based design for influence computation, called SKIM, which scales to graphs with billions of edges, with one to two orders of magnitude speedup over the best greedy methods.
A Hub-Based Labeling Algorithm for Shortest Paths in Road Networks
TLDR
An implementation of the labeling algorithm that is faster than any existing method on continental road networks and has the best time bounds is described.
Customizable Route Planning
We present an algorithm to compute shortest paths on continental road networks with arbitrary metrics (cost functions). The approach supports turn costs, enables real-time queries, and can
Engineering Route Planning Algorithms
TLDR
An overview of the techniques enabling the development of algorithms for route planning in transportation networks and point out frontiers of ongoing research on more challenging variants of the problem that include dynamically changing networks, time-dependent routing, and flexible objective functions.
Graph Partitioning with Natural Cuts
TLDR
A novel approach to graph partitioning based on the notion of natural cuts, called PUNCH, which obtains the best known partitions for continental-sized networks, significantly improving on previous results.
Landmark-Based Routing in Dynamic Graphs
TLDR
It turns out that by increasing the efficiency of ALT, one is able to perform fast (down to 20 ms on the Western European network) random queries in a dynamic scenario without updating the preprocessing as long as the changes in the network are moderate.
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