Results 31 to 40 of about 1,370,090 (279)
Old and new generalizations of line graphs
International Journal of Mathematics and Mathematical Sciences, 2004 Line graphs have been studied for over seventy years. In 1932, H. Whitney showed that for connected graphs, edge-isomorphism implies isomorphism except for K3 and K1,3.
Jay Bagga
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Nonplanarity of Iterated Line Graphs
Journal of Mathematics, 2020 The 1-crossing index of a graph G is the smallest integer k such that the kth iterated line graph of G has crossing number greater than 1. In this paper, we show that the 1-crossing index of a graph is either infinite or it is at most 5.
Jing Wang
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MathematicsThe shortest path problem is fundamental in graph theory and has been studied extensively due to its practical importance. Despite this aspect, finding the shortest path between two nodes remains a significant challenge in many applications, as it often ...
Adrien Durand +3 more
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Graph schema and best graph type to compare discrete groups: Bar, line, and pie
Frontiers in Psychology, 2022 Different graph types may differ in their suitability to support group comparisons, due to the underlying graph schemas. This study examined whether graph schemas are based on perceptual features (i.e., each graph type, e.g., bar or line graph, has its ...
Fang Zhao, Robert Gaschler
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Discrete Mathematics, 2011 Boxicity of a graph H, denoted by box(H), is the minimum integer k such that H is an intersection graph of axis-parallel k-dimensional boxes in R^k. In this paper, we show that for a line graph G of a multigraph, box(G) <= 2 (\lceil log_2(log_2( )) \rceil + 3) + 1, where denotes the maximum degree of G. Since <= 2( - 1), for any line graph
Chandran, Sunil L +2 more
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On chordal graph and line graph squares [PDF]
Discrete Applied Mathematics, 2018 In this work we investigate the chordality of squares and line graph squares of graphs. We prove a sufficient condition for the chordality of squares of graphs not containing induced cycles of length at least five. Moreover, we characterize the chordality of graph squares by forbidden subgraphs.
Robert Scheidweiler +1 more
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Closeness of Some Graph Operations
Computing OpenCloseness is an important measure of network centrality. In this paper, we will calculate the closeness of graphs, created by using operations on graphs. We will prove a formula for the closeness of shadow graphs.
Chavdar Dangalchev
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Bar 1-Visibility Drawings of 1-Planar Graphs
, 2013 A bar 1-visibility drawing of a graph $G$ is a drawing of $G$ where each vertex is drawn as a horizontal line segment called a bar, each edge is drawn as a vertical line segment where the vertical line segment representing an edge must connect the ...
A.M. Dean +13 more
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Graph Equation for Line Graphs and m-Step Graphs [PDF]
Graphs and Combinatorics, 2011 zbMATH Open Web Interface contents unavailable due to conflicting licenses.
Kim, Seog-Jin +4 more
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FEBS Letters, EarlyView.Enteropathogenic E. coli (EPEC) infects the human intestinal epithelium, resulting in severe illness and diarrhoea. In this study, we compared the infection of cancer‐derived cell lines with human organoid‐derived models of the small intestine. We observed a delayed in attachment, inflammation and cell death on primary cells, indicating that host ...
Mastura Neyazi +5 more
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