Stefan Hougardy

According to our database, Stefan Hougardy authored at least 52 papers between 1993 and 2024.

Collaborative distances:

• Dijkstra number of four.
• Erdős number of three.

2024

The Bottom-Left Algorithm for the Strip Packing Problem.

Stefan Hougardy, Bart Zondervan

CoRR, 2024

The k-Opt algorithm for the Traveling Salesman Problem has exponential running time for k≥5.

Sophia Heimann, Hung P. Hoang, Stefan Hougardy

CoRR, 2024

2023

A Fast Optimal Double-row Legalization Algorithm.

Stefan Hougardy, Meike Neuwohner, Ulrike Schorr

ACM Trans. Design Autom. Electr. Syst., September, 2023

The Approximation Ratio of the <i>k</i>-Opt Heuristic for the Euclidean Traveling Salesman Problem.

Ulrich A. Brodowsky, Stefan Hougardy, Xianghui Zhong

SIAM J. Comput., August, 2023

Local elimination in the traveling salesman problem.

William J. Cook, Keld Helsgaun, Stefan Hougardy, Rasmus T. Schroeder

CoRR, 2023

2021

Hard to solve instances of the Euclidean Traveling Salesman Problem.

Stefan Hougardy, Xianghui Zhong

Math. Program. Comput., 2021

The Approximation Ratio of the k-Opt Heuristic for the Euclidean Traveling Salesman Problem.

Ulrich A. Brodowsky, Stefan Hougardy, Xianghui Zhong

CoRR, 2021

The Approximation Ratio of the 2-Opt Heuristic for the Euclidean Traveling Salesman Problem.

Ulrich A. Brodowsky, Stefan Hougardy

Proceedings of the 38th International Symposium on Theoretical Aspects of Computer Science, 2021

2020

BonnCell: Automatic Cell Layout in the 7-nm Era.

Pascal Van Cleeff, Stefan Hougardy, Jannik Silvanus, Tobias Werner

IEEE Trans. Comput. Aided Des. Integr. Circuits Syst., 2020

The approximation ratio of the 2-Opt Heuristic for the metric Traveling Salesman Problem.

Stefan Hougardy, Fabian Zaiser, Xianghui Zhong

Oper. Res. Lett., 2020

2017

Dijkstra meets Steiner: a fast exact goal-oriented Steiner tree algorithm.

Stefan Hougardy, Jannik Silvanus, Jens Vygen

Math. Program. Comput., 2017

Automatic Cell Layout in the 7nm Era.

Pascal Cremer, Stefan Hougardy, Jan Schneider, Jannik Silvanus

Proceedings of the 2017 ACM on International Symposium on Physical Design, 2017

2016

An exact algorithm for wirelength optimal placements in VLSI design.

Julia Funke, Stefan Hougardy, Jan Schneider

Integr., 2016

2015

The approximation ratio of the greedy algorithm for the metric traveling salesman problem.

Judith Brecklinghaus, Stefan Hougardy

Oper. Res. Lett., 2015

On the nearest neighbor rule for the metric traveling salesman problem.

Stefan Hougardy, Mirko Wilde

Discret. Appl. Math., 2015

2014

On the integrality ratio of the subtour LP for Euclidean TSP.

Stefan Hougardy

Oper. Res. Lett., 2014

Edge Elimination in TSP Instances.

Stefan Hougardy, Rasmus T. Schroeder

Proceedings of the Graph-Theoretic Concepts in Computer Science, 2014

2013

BonnCell: Automatic layout of leaf cells.

Stefan Hougardy, Tim Nieberg, Jan Schneider

Proceedings of the 18th Asia and South Pacific Design Automation Conference, 2013

2011

On packing squares into a rectangle.

Stefan Hougardy

Comput. Geom., 2011

2010

The Floyd-Warshall algorithm on graphs with negative cycles.

Stefan Hougardy

Inf. Process. Lett., 2010

Surface Realization with the Intersection Segment Functional.

Stefan Hougardy, Frank H. Lutz, Mariano Zelke

Exp. Math., 2010

2008

Linear Time Approximation Algorithms for Degree Constrained Subgraph Problems.

Stefan Hougardy

Proceedings of the Research Trends in Combinatorial Optimization, 2008

2007

Computation of best possible low degree expanders.

Stefan Hougardy, Ivo Köthnig

Discret. Appl. Math., 2007

2006

Lower bounds for the relative greedy algorithm for approximating Steiner trees.

Stefan Hougardy, Stefan Kirchner

Networks, 2006

Approximating weighted matchings in parallel.

Stefan Hougardy, Doratha E. Drake Vinkemeier

Inf. Process. Lett., 2006

On a conjecture of Hoàng and Tu concerning perfectly orderable graphs.

Stefan Hougardy

Discret. Math., 2006

Classes of perfect graphs.

Stefan Hougardy

Discret. Math., 2006

2005

A linear-time approximation algorithm for weighted matchings in graphs.

Doratha E. Drake Vinkemeier, Stefan Hougardy

ACM Trans. Algorithms, 2005

2004

Perfectness is an Elusive Graph Property.

Stefan Hougardy, Annegret Wagler

SIAM J. Comput., 2004

Comparison of 2<i>D</i> Similarity and 3<i>D</i> Superposition. Application to Searching a Conformational Drug Database.

Martin Thimm, Andrean Goede, Stefan Hougardy, Robert Preissner

J. Chem. Inf. Model., 2004

On approximation algorithms for the terminal Steiner tree problem.

Doratha E. Drake, Stefan Hougardy

Inf. Process. Lett., 2004

On simplicial and co-simplicial vertices in graphs.

Chính T. Hoàng, Stefan Hougardy, Frédéric Maffray, Nadimpalli V. R. Mahadev

Discret. Appl. Math., 2004

2003

A simple approximation algorithm for the weighted matching problem.

Doratha E. Drake, Stefan Hougardy

Inf. Process. Lett., 2003

Accelerating screening of 3D protein data with a graph theoretical approach.

Cornelius Frömmel, Christoph Gille, Andrean Goede, Clemens Gröpl, Stefan Hougardy, Till Nierhoff, Robert Preissner, Martin Thimm

Bioinform., 2003

Linear Time Local Improvements for Weighted Matchings in Graphs.

Doratha E. Drake, Stefan Hougardy

Proceedings of the Experimental and Efficient Algorithms, Second International Workshop, 2003

Improved Linear Time Approximation Algorithms for Weighted Matchings.

Doratha E. Drake, Stefan Hougardy

Proceedings of the Approximation, 2003

2002

Recursive generation of partitionable graphs.

Endre Boros, Vladimir Gurvich, Stefan Hougardy

J. Graph Theory, 2002

Steiner trees in uniformly quasi-bipartite graphs.

Clemens Gröpl, Stefan Hougardy, Till Nierhoff, Hans Jürgen Prömel

Inf. Process. Lett., 2002

Polynomial time recognition of P4-structure.

Ryan B. Hayward, Stefan Hougardy, Bruce A. Reed

Proceedings of the Thirteenth Annual ACM-SIAM Symposium on Discrete Algorithms, 2002

2001

Lower Bounds for Approximation Algorithms for the Steiner Tree Problem.

Clemens Gröpl, Stefan Hougardy, Till Nierhoff, Hans Jürgen Prömel

Proceedings of the Graph-Theoretic Concepts in Computer Science, 2001

1999

On wing-perfect graphs.

Stefan Hougardy

J. Graph Theory, 1999

A 1.598 Approximation Algorithm for the Steiner Problem in Graphs.

Stefan Hougardy, Hans Jürgen Prömel

Proceedings of the Tenth Annual ACM-SIAM Symposium on Discrete Algorithms, 1999

1998

Uniquely Colourable Graphs and the Hardness of Colouring Graphs of Large Girth.

Thomas Emden-Weinert, Stefan Hougardy, Bernd Kreuter

Comb. Probab. Comput., 1998

1997

Wing-triangulated graphs are perfect.

Stefan Hougardy, Van Bang Le, Annegret Wagler

J. Graph Theory, 1997

Does the Jones Polynomial Detect Unknottedness?

Oliver T. Dasbach, Stefan Hougardy

Exp. Math., 1997

Perfect graphs with unique P₄-structure.

Stefan Hougardy

Discret. Math., 1997

Proof Checking and Non-approximability.

Stefan Hougardy

Proceedings of the Lectures on Proof Verification and Approximation Algorithms. (the book grow out of a Dagstuhl Seminar, 1997

1996

On the <i>P</i>₄-Structure of Perfect Graphs V. Overlap Graphs.

Chính T. Hoàng, Stefan Hougardy, Frédéric Maffray

J. Comb. Theory, Ser. B, 1996

Even pairs and the strong perfect graph conjecture.

Stefan Hougardy

Discret. Math., 1996

1995

Even and odd pairs in linegraphs of bipartite graphs.

Stefan Hougardy

Eur. J. Comb., 1995

1994

Probabilistically checkable proofs and their consequences for approximation algorithms.

Stefan Hougardy, Hans Jürgen Prömel, Angelika Steger

Discret. Math., 1994

1993

Counterexamples to three conjectures concerning perfect graphs.

Stefan Hougardy

Discret. Math., 1993