Results 51 to 60 of about 20,236 (296)

Planar lattices and planar graphs

Journal of Combinatorial Theory, Series B, 1976
AbstractIt is shown that a finite lattice is planar if and only if the (undirected) graph obtained from its (Hasse) diagram by adding an edge between its least and greatest elements is a planar graph.
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Clustered Level Planarity [PDF]

, 2004
Planarity is an important concept in graph drawing. It is generally accepted that planar drawings are well understandable. Recently, several variations of planarity have been studied for advanced graph concepts such as k-level graphs and clustered graphs.
Michael Forster, Christian Bachmaier
core   +1 more source

The expected sum of edge lengths in planar linearizations of trees

Journal of Language Modelling
Dependency trees have proven to be a very successful model to represent the syntactic structure of sentences of human languages. In these structures, vertices are words and edges connect syntacticallydependent words.
Lluís Alemany-Puig, Ramon Ferrer-i-Cancho   +1 more
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On the planar edge-length ratio of planar graphs

J. Comput. Geom., 2019
The edge-length ratio of a straight-line drawing of a graph is the ratio between the lengths of the longest and of the shortest edge in the drawing. The planar edge-length ratio of a planar graph is the minimum edge-length ratio of any planar straight-line drawing of the graph. In this paper, we study the planar edge-length ratio of planar graphs.
Borrazzo, Manuel, Frati, Fabrizio
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Line graph embedding of co-intersection graph of ideals of commutative rings

AKCE International Journal of Graphs and Combinatorics
This research paper focuses on the co-intersection graph of a commutative ring [Formula: see text]. The co-intersection graph of [Formula: see text] denoted by [Formula: see text] is a simple graph with vertices that are non-trivial ideals of [Formula ...
Ali Al Khabyah, Kholood Alnefaie, Shabir Ahmad Mir, Nadeem ur Rehman, Junaid Nisar   +4 more
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Regularity and Planarity of Token Graphs

Discussiones Mathematicae Graph Theory, 2017
Let G = (V, E) be a graph of order n and let 1 ≤ k < n be an integer. The k-token graph of G is the graph whose vertices are all the k-subsets of V, two of which are adjacent whenever their symmetric difference is a pair of adjacent vertices in G.
Carballosa Walter, Fabila-Monroy Ruy, Leaños Jesús, Rivera Luis Manuel   +3 more
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Noise modeling and depth calibration for Time-Of-Flight cameras

ELCVIA Electronic Letters on Computer Vision and Image Analysis, 2014
thesis extended ...
Amira Belhedi
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Planar diagrams

Communications in Mathematical Physics, 1978
The authors describe their method for counting planar Feynman diagrams of quantum field theory. Mathematicians who are not familiar with the current jargon of quantum field theory are likely to find this paper rather difficult to follow. In order to demonstrate the usefulness of their method, the authors calculate the ground state energy of a system of
Brézin, E., Itzykson, C., Parisi, G., Zuber, J. B.   +3 more
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Trémaux trees and planarity [PDF]

, 2012
We present a characterization of planarity based on Trémaux trees (i.e. DFS trees), from which we deduce a rather simple planarity test algorithm. We finally recall a theorem on “cotree critical non-planar graphs” which very much simplifies the search ...
Ossona de Mendez, Patrice, Hubert de Fraysseix, Patrice Ossona de Mendez, de Fraysseix, Hubert   +3 more
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Notes on Maskit's planarity theorem [PDF]

, 2022
We give an account of the Planarity Theorem of Maskit. This gives a classification of finitely generated groups acting effectively properly discontinuously by orientation-preserving homeomorphisms on a planar surface.
Bowditch, B. H.
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