Bernd Hauck
Bernd Hauck
I work as a research assistant at the Institute of Telematics since June 2007.
Teaching
- Lecture: Web Engineering
Projects
- TSSSA - Time- and Space-efficient Self-Stabilizing Algorithms
Publications
Volker Turau and Bernd Hauck. A new Analysis of a Self-Stabilizing Maximum Weight Matching Algorithm with Approximation Ratio 2. Theoretical Computer Science, 412(40):5527–5540, September 2011. Stabilization, Safety and Security.
@Article{Telematik_HT_2010_TCS_Matching,
author = {Volker Turau and Bernd Hauck},
title = {A new Analysis of a Self-Stabilizing Maximum Weight Matching Algorithm with Approximation Ratio 2},
pages = {5527-5540},
journal = {Theoretical Computer Science},
volume = {412},
number = {40},
month = sep,
year = 2011,
keywords = {Self-stabilizing algorithms, approximation algorithm, weighted matching, distributed algorithms},
issn = {0304-3975},
note = {Stabilization, Safety and Security},
}
Abstract:
The maximum weight matching problem is a fundamental problem in graph theory
with a variety of important applications. Recently Manne and Mjelde presented
the first self-stabilizing algorithm computing a 2-approximation of the optimal
solution. They established that their algorithm stabilizes after O(2^n) (resp.
O(3^n)) moves under a central (resp. distributed) scheduler. This paper contributes
a new analysis improving these bounds considerably. In particular it is shown that
the algorithm stabilizes after O(nm) moves under the central scheduler and that
a modified version of the algorithm also stabilizes after O(nm) moves under the
distributed scheduler. The paper presents a new proof technique based on graph
reduction to analyze the complexity of self-stabilizing algorithms.
Volker Turau and Bernd Hauck. A fault-containing self-stabilizing (3 -
2/(Delta+1))-approximation algorithm for vertex cover in anonymous
networks. Theoretical Computer Science, 412(33):4361–4371, 2011.
@Article{Telematik_HT_2011_TCSVC,
author = {Volker Turau and Bernd Hauck},
title = {A fault-containing self-stabilizing (3 -
2/(Delta+1))-approximation algorithm for vertex cover in anonymous
networks},
pages = {4361-4371},
journal = {Theoretical Computer Science},
volume = {412},
number = {33},
year = 2011,
keywords = {Self-stabilizing algorithms, Fault tolerance,
Distributed algorithms, Graph algorithms},
}
Abstract:
The non-computability of many distributed tasks in
anonymous networks is well known. This paper presents a deterministic
self-stabilizing algorithm to compute a 3 - (2 /
(Delta+1))-approximation of a minimum vertex cover in anonymous
networks. The algorithm operates under the distributed unfair
scheduler, stabilizes after O(n+m) moves respectively O(Delta)
rounds, and requires O(log n) storage per node. Recovery from a
single fault is reached within a constant time and the contamination
number is O(Delta). For trees the algorithm computes a
2-approximation of a minimum vertex cover.
Volker Turau and Bernd Hauck. A Self-Stabilizing Approximation Algorithm for Vertex
Cover in Anonymous Networks. In Proceedings of the 11th International Symposium on
Stabilization, Safety, and Security of Distributed Systems (SSS'09), Springer, November 2009, pp. 341–353. Lyon, France.
@InProceedings{Telematik_HT_2009_VC,
author = {Volker Turau and Bernd Hauck},
title = {A Self-Stabilizing Approximation Algorithm for Vertex
Cover in Anonymous Networks},
booktitle = {Proceedings of the 11th International Symposium on
Stabilization, Safety, and Security of Distributed Systems (SSS'09)},
pages = {341-353},
series = {Lecture Notes in Computer Science},
volume = {5873},
publisher = {Springer},
day = {3-6},
month = nov,
year = 2009,
location = {Lyon, France},
}
Abstract:
This paper presents a deterministic self-stabilizing
algorithm that
computes a 3-approximation vertex cover in anonymous
networks. It
reaches a legal state after O(n+m) moves or 2n + 1 rounds
respectively and recovers from a single fault within a constant
containment time. The contamination number is 2 Delta + 1. An
enhanced version of this algorithm achieves a 2-approximation on
trees.
The complete list of publications is available separately.