Results 21 to 30 of about 844 (217)

Clustering Cycles into Cycles of Clusters

Journal of Graph Algorithms and Applications, 2005
In this paper we study simple families of clustered graphs that are highly unconnected. We start by studying 3-cluster cycles, which are clustered graphs such that the underlying graph is a simple cycle and there are three clusters all at the same level.
Pier Francesco Cortese, Giuseppe Di Battista, Maurizio Patrignani, Maurizio Pizzonia   +3 more
doaj   +1 more source

Computing NodeTrix Representations of Clustered Graphs

Journal of Graph Algorithms and Applications, 2018
NodeTrix representations are a popular way to visualize clustered graphs; they represent clusters as adjacency matrices and inter-cluster edges as curves connecting the matrix boundaries.
Giordano Da Lozzo, Giuseppe Di Battista, Fabrizio Frati, Maurizio Patrignani   +3 more
doaj   +1 more source

Planarity of Overlapping Clusterings Including Unions of Two Partitions

Journal of Graph Algorithms and Applications, 2017
We consider clustered planarity with overlapping clusters as introduced by Didimo et al. (Didimo, Giordano, Liotta, JGAA, 2008). It can be deduced from a proof in Athenstädt et al. (J. C. Athenstädt, T. Hartmann, and M.
Jan Christoph Athenstädt, Sabine Cornelsen   +1 more
doaj   +1 more source

Clustered Planarity: Small Clusters in Eulerian Graphs [PDF]

, 2008
We present several polynomial-time algorithms for c-planarity testing for clustered graphs with clusters of size at most three. The most general result concerns a special class of Eulerian graphs, namely graphs obtained froma fixed-size 3-connected graph bymultiplying and then subdividing edges.
Eva Jelínková, Jan Kára, Jan Kratochvíl, Martin Pergel, Ondrej Suchý 0001, Tomás Vyskocil   +5 more
openaire   +1 more source

Intact Planar Abstraction of Buildings via Global Normal Refinement from Noisy Oblique Photogrammetric Point Clouds

ISPRS International Journal of Geo-Information, 2018
Oblique photogrammetric point clouds are currently one of the major data sources for the three-dimensional level-of-detail reconstruction of buildings.
Qing Zhu, Feng Wang, Han Hu, Yulin Ding, Jiali Xie, Weixi Wang, Ruofei Zhong   +6 more
doaj   +1 more source

Splitting Clusters to Get C-Planarity [PDF]

, 2010
In this paper we introduce a generalization of the c-planarity testing problem for clustered graphs. Namely, given a clustered graph, the goal of the Split-C-Planarity problem is to split as few clusters as possible in order to make the graph c-planar. Determining whether zero splits are enough coincides with testing c-planarity.
Patrizio Angelini, Fabrizio Frati, Maurizio Patrignani   +2 more
openaire   +2 more sources

On the Complexity of Clustered-Level Planarity and T-Level Planarity

CoRR, 2014
In this paper we study two problems related to the drawing of level graphs, that is, T-LEVEL PLANARITY and CLUSTERED-LEVEL PLANARITY. We show that both problems are NP-complete in the general case and that they become polynomial-time solvable when restricted to proper instances.
Patrizio Angelini, Giordano Da Lozzo, Giuseppe Di Battista, Fabrizio Frati, Vincenzo Roselli   +4 more
openaire   +2 more sources

Constrained Planarity in Practice -- Engineering the Synchronized Planarity Algorithm

Journal of Graph Algorithms and Applications
In the constrained planarity setting, we ask whether a graph admits a planar drawing that additionally satisfies a given set of constraints. These constraints are often derived from very natural problems; prominent examples are Level Planarity, where ...
Simon Dominik Fink, Ignaz Rutter
doaj   +1 more source

Planar Clusters

, 2004
We provide upper and lower bounds on the least-perimeter way to enclose and separate n regions of equal area in the plane. Along the way, inside the hexagonal honeycomb, we provide minimizers for each n .
Heppes, Aladar, Morgan, Frank
openaire   +2 more sources

Low‐Angle Grain Boundaries and Re‐Segregation in Single‐Crystalline Ni‐Base Superalloys

Advanced Engineering Materials, EarlyView.
This work demonstrates that Re‐segregation at low‐angle grain boundaries (LAGBs) in Ni‐base superalloys is influenced by misorientation angle. Advanced microscopy and atom probe tomography reveal that higher misorientation angles increases Re‐segregation.
Alireza B. Parsa, Aparna Saksena, Alesander Kostka, Pascal Thome, Felicitas Scholz, Alexandre Mussi, Christoph Somsen, Baptiste Gault, Jan Frenzel, Gunther Eggeler   +9 more
wiley   +1 more source