Extremizing algebraic connectivity subject to graph theoretic constraints

Extremizing algebraic connectivity subject to graph theoretic constraints

Temporal Network Optimization Subject to Connectivity Constraints

In this work we consider temporal networks, i.e. networks defined by a labeling λ assigning to each edge of an underlying graph G a set of discrete time-labels. The labels of an edge, which are natural numbers, indicate the discrete time moments at which the edge is available. We focus on path problems of temporal networks. In particular, we consider time-respecting paths, i.e. paths whose edge...

Landscape Connectivity: A Graph-Theoretic Perspective

Ecologists are familiar with two data structures commonly used to represent landscapes. Vector-based maps delineate land cover types as polygons, while raster lattices represent the landscape as a grid. Here we adopt a third lattice data structure, the graph. A graph represents a landscape as a set of nodes (e.g., habitat patches) connected to some degree by edges that join pairs of nodes funct...

Mechanical Systems Subject to Holonomic Constraints: Diierential-algebraic Formulations and Conservative Integration Mechanical Systems Subject to Holonomic Constraints: Diierential-algebraic Formulations and Conservative Integration

The numerical integration in time of the equations of motion for mechanical systems subject to holonomic constraints is considered. Schemes are introduced for the direct treatment of a diierential-algebraic form of the equations that preserve the constraints, the total energy, and other integrals such as linear and angular momentum arising from aane symmetries. Moreover, the schemes can be show...

Algebraic and graph-theoretic properties of infinite n-posets

A Σ-labeled n-poset is an (at most) countable set, labeled in the set Σ, equipped with n partial orders. The collection of all Σ-labeled n-posets is naturally equipped with n binary product operations and n ω-ary product operations. Moreover, the ω-ary product operations give rise to n ω-power operations. We show that those Σ-labeled n-posets that can be generated from the singletons by the bin...