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Abstract We propose and unify classes of different models for information propagation over graphs. In a first class, propagation is modelled as a wave, which emanates from a set ofknownnodes at an initial time, to all otherunknownnodes at later times with an ordering determined by the arrival time of the information wave front. A second class of models is based on the notion of a travel time along paths between nodes. The time of information propagation from an initialknownset of nodes to a node is defined as the minimum of a generalised travel time over subsets of all admissible paths. A final class is given by imposing a local equation of an eikonal form at eachunknownnode, with boundary conditions at theknownnodes. The solution value of the local equation at a node is coupled to those of neighbouring nodes with lower values. We provide precise formulations of the model classes and prove equivalences between them. Finally, we apply the front propagation models on graphs to semi-supervised learning via label propagation and information propagation on trust networks.
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Front propagation and blocking of reaction–diffusion systems in cylinders
Abstract In this paper, we consider a bistable monotone reaction–diffusion system in cylindrical domains. We first prove the existence of the entire solution emanating from a planar front. Then, it is proved that the entire solution converges to a planar front if the propagation is complete and the domain is bilaterally straight. Finally, we give some geometrical conditions on the domain such that the propagation of the entire solution is complete or incomplete, respectively.
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- Award ID(s):
- 1826801
- PAR ID:
- 10322461
- Date Published:
- Journal Name:
- Nonlinearity
- Volume:
- 34
- Issue:
- 10
- ISSN:
- 0951-7715
- Format(s):
- Medium: X
- Sponsoring Org:
- National Science Foundation
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- Free Publicly Accessible Full Text
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Accepted Manuscript1.0
- Journal Article:
- https://doi.org/10.1088/1361-6544/abd529
