IMMANUEL (GOD WITH US)

Poem by Ben Strasse

Dynamic Time-Dependent Routing in Road Networks Through Sampling

We study the earliest arrival and profile problems in road networks with time-dependent functions as arc weights and dynamic updates. We present and experimentally evaluate simple, sampling-based, heuristic algorithms. Our evaluation is performed on large, current, production-grade road graph data with time-dependent arc weights. It clearly shows that the proposed algorithms are fast and compute paths with a sufficiently small error for most practical applications. We experimentally compare our algorithm against the current state-of-the-art. Our experiments reveal, that the memory consumption of existing algorithms is prohibitive on large instances. Our approach does not suffer from this limitation. Further, our algorithm is the only competitor able to answer profile queries on all test instances below 50ms. As our algorithm is simple to implement, we believe that it is a good fit for many realworld applications

PACE Solver Description: Tree Depth with FlowCutter

We describe the FlowCutter submission to the PACE 2020 heuristic tree-depth challenge. The task of the challenge consists of computing an elimination tree of small height for a given graph. At its core our submission uses a nested dissection approach, with FlowCutter as graph bisection algorithm

Correspondence between Multilevel Graph Partitions and Tree Decompositions

We present amapping between rooted tree decompositions and node separator basedmultilevel graph partitions. Significant research into both tree decompositions and graph partitions exists. We hope that our result allows for an easier knowledge transfer between the two research avenues