Results 21 to 30 of about 139,638 (260)
About Directed d-Convex Simple Graphs [PDF]
Computer Science Journal of Moldova, 2008 In this article we introduce a pseudo-metric on directed graphs, which forms there a family of convex sets. The graphs without d-convex sets, except empty set, sets of one vertex and set of all vertexes, are called d-convex simple.
Nadejda Sur, Sergiu Cataranciuc
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Direct reciprocity on graphs [PDF]
Journal of Theoretical Biology, 2007 Direct reciprocity is a mechanism for the evolution of cooperation based on the idea of repeated encounters between the same two individuals. Here we examine direct reciprocity in structured populations, where individuals occupy the vertices of a graph. The edges denote who interacts with whom. The graph represents spatial structure or a social network.
Ohtsuki, Hisashi, Nowak, Martin
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Extending Undirected Graph Techniques to Directed Graphs via Category Theory
MathematicsWe use Category Theory to construct a ‘bridge’ relating directed graphs with undirected graphs, such that the notion of direction is preserved. Specifically, we provide an isomorphism between the category of simple directed graphs and a category we call ‘
Sebastian Pardo-Guerra +4 more
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Directed random geometric graphs [PDF]
Journal of Complex Networks, 2019 Abstract Many real-world networks are intrinsically directed. Such networks include activation of genes, hyperlinks on the internet and the network of followers on Twitter among many others. The challenge, however, is to create a network model that has many of the properties of real-world networks such as power-law degree distributions ...
Michel, Jesse +4 more
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Gromov Hyperbolicity in Directed Graphs [PDF]
Symmetry, 2020 In this paper, we generalize the classical definition of Gromov hyperbolicity to the context of directed graphs and we extend one of the main results of the theory: the equivalence of the Gromov hyperbolicity and the geodesic stability. This theorem has potential applications to the development of solutions for secure data transfer on the internet.
Ana Portilla +3 more
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Directed hypergraph attention network for traffic forecasting
IET Intelligent Transport Systems, 2022 In traffic systems, traffic forecasting is a critical issue, which has attracted much interest from researchers. It is a challenging task due to the complex spatial‐temporal patterns of traffic data.
Xiaoyi Luo, Jiaheng Peng, Jun Liang
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Reducing bias through directed acyclic graphs
BMC Medical Research Methodology, 2008 Background The objective of most biomedical research is to determine an unbiased estimate of effect for an exposure on an outcome, i.e. to make causal inferences about the exposure.
Platt Robert W, Shrier Ian
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Large-scale DCMs for resting-state fMRI [PDF]
Network Neuroscience, 2017 This paper considers the identification of large directed graphs for resting-state brain networks based on biophysical models of distributed neuronal activity, that is, effective connectivity.
Adeel Razi +8 more
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Hierarchy Depth in Directed Networks
Entropy, 2022 In this study, we explore the depth measures for flow hierarchy in directed networks. Two simple measures are defined—rooted depth and relative depth—and their properties are discussed. The method of loop collapse is introduced, allowing investigation of
Krzysztof Suchecki, Janusz A. Hołyst
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Therapeutic Apheresis and Dialysis, EarlyView.ABSTRACT Secondary hyperparathyroidism (SHPT) is a common complication in patients receiving maintenance dialysis, driven by calcium and phosphate metabolism disturbances. Calcimimetics are central to the management of SHPT by enhancing calcium‐sensing receptor sensitivity and reducing parathyroid hormone secretion.
Fumihiko Koiwa +3 more
wiley +1 more source