A method is presented for the calculation of all exact ground states of diluted Ising antiferromagnets and random field Ising systems in an arbitrary range of magnetic fields Bϵ [Bstart, Bend] resp. Δϵ [Δstart, Δend]. It works by calculating all jump-fields B, Δ where the system changes...

The statistical tools of Complex Network Analysis are of useful to understand salient properties of complex systems, may these be natural or pertaining human engineered infrastructures. One of these that is receiving growing attention for its societal relevance is that of electricity...

In this contribution we show that natural rock fracture networks, acting as media for the delivery of a variety of geological fluids, can be studied by using the principles of complex systems. Natural networks at different length scales (from the metre to the micrometer) have been analysed by...

A drug use epidemic can be represented by a finite number of states and transition rules that govern the dynamics of drug use in each discrete time step. This paper investigates the spread of drug use in a community where some users are in treatment and others are not in treatment, citing South...

We present a fast (∼ O (N3)) algorithm which calculates groundstates of Ising spin glasses approximately. It works by randomly selecting clusters of spins which exhibit no frustrations. The spins which were not selected, contribute to the local fields of the selected spins. For the...

Transportation systems, being real-life examples of networks, are particularly interesting to analyze from the viewpoint of the new and rapidly emerging field of network science. Two particular concepts seem to be particularly relevant: scale-free patterns and small-worlds. By looking at 33...

A quantum particle on a general discrete structure with a local external potential is described by a generalized tight-binding Hamiltonian on a graph. Here, we show that this model can be naturally mapped on a classical statistical model (the Gaussian model) on the same graph. This equivalence...

In this paper, the important issue of Laplacian eigenvalue distributions is investigated through theory-guided extensive numerical simulations, for four typical complex network models, namely, the ER random-graph networks, WS and NW small-world networks, and BA scale-free networks. It is found...

The balance between the supply and demand of some kind of resource is critical for the functionality and security of many complex networks. Local contingencies that break this balance can cause a global collapse. These contingencies are usually dealt with by spare capacity, which is costly...

The objective of this work is to propose a new methodology to detect the imminence of abrupt changes in the stock market by combining a numerical indicator based on the wavelet decomposition technique with a measure of the interdependency of the markets using graph theory. While the indicator...