[1] Based on the analysis of a low-order tropical atmosphere-ocean model we propose a nonlinear mechanism explaining several features of the observed El Niño-Southern Oscillation (ENSO) phenomenon: ENSO irregularity, ENSO Amplitude Modulations and decadal tropical climate variability. The mechanism suggested here is based on the idea of homoclinic/heteroclinic orbits, an inherently nonlinear co...

We present findings from an analysis of the fractal dimension solar supergranulation as a function latitude, supergranular cell size and rotation, employing spectroheliographic data in Ca II K line cycle no. 23. find that tends to decrease about 1.37 at equator 1 20 degree latitude either hemisphere, suggesting rotation rate has effect augmenting irregularity boundaries. Considering is directly...

In this paper, we introduce the notions of product vague graph, balanced product vague graph, irregularity and total irregularity of any irregular vague graphs and some results are presented. Also, density and balanced irregular vague graphs are discussed and some of their properties are established. Finally we give an application of vague digraphs.

The total irregularity of a graph G is defined as 〖irr〗_t (G)=1/2 ∑_(u,v∈V(G))▒〖|d_u-d_v |〗, where d_u denotes the degree of a vertex u∈V(G). In this paper by using the Gini index, we obtain the ordering of the total irregularity index for some classes of connected graphs, with the same number of vertices.

The irregularity of a simple undirected graph G was defined by Albertson [5] as irr(G) = ∑ uv∈E(G) |dG(u)− dG(v)|, where dG(u) denotes the degree of a vertex u ∈ V (G). In this paper we consider the irregularity of graphs under several graph operations including join, Cartesian product, direct product, strong product, corona product, lexicographic product, disjunction and symmetric difference. ...

Since the refractory period was first described by Fontana in 1760,7 a variety of techniques has been employed to study the time-course of recovery of heart excitability and its relation to mechanical and electrical events during the cardiac cycle. Bowditch,7 in 1871, stimulated the perfused apex of the frog heart with rhythmic shocks at intervals of 1, 2, 3, 4, or more seconds. He found that s...