Given a simple, undirected graph G, Budinich (Discret Appl Math 127:535–543, 2003) proposed a lower bound on the clique number of G by combining the quadratic programming formulation of the clique number due to Motzkin and Straus (Can J Math 17:533–540, 1965) with the spectral decomposition...

Given a simple, undirected graph G, Budinich (Discret Appl Math 127:535–543, 2003) proposed a lower bound on the clique number of G by combining the quadratic programming formulation of the clique number due to Motzkin and Straus (Can J Math 17:533–540, 1965) with the spectral decomposition...

We analyze growing networks ranging from collaboration graphs of scientists to the network of similarities defined among the various transcriptional profiles of living cells. For the explicit demonstration of the scale-free nature and hierarchical organization of these graphs, a deterministic...

The representation of complex systems as networks is inappropriate for the study of certain problems. We show several examples of social, biological, ecological and technological systems where the use of complex networks gives very limited information about the structure of the system....

AMS Mathematics Subject Classification: 05C50.

Abstract: The energy of a graph Γ is the sum of the absolute values of the eigenvalues of the adjacency matrix of Γ. Seidel switching is an operation on the edge set of Γ. In some special cases Seidel switching does not change the spectrum, and therefore the energy. Here we investigate when...

We describe the use of machine learning methods in the analysis of spatial soil fertility, soil physical characteristics, and yield data, with a particular objective of determining local (field- to farm-scale) crop response patterns. For effective prescriptive use, the output of these tools is...

Forestry programs are frequently invoked as having potential for mitigation of greenhouse gas emissions. Most studies have attempted to quantify the potential impact of forest programs on carbon uptake and the potential costs of such programs. In this paper, we will attempt instead to focus on...