Let $S(G^{sigma})$ be the skew-adjacency matrix of the oriented graph $G^{sigma}$, which is obtained from a simple undirected graph $G$ by assigning an orientation $sigma$ to each of its edges. The skew energy of an oriented graph $G^{sigma}$ is defined as the sum of absolute values of all eigenvalues of $S(G^{sigma})$. Two oriented graphs are said to be skew equienergetic iftheir skew energies...

the remarkable development of sciences and technologies in the world of]o today has apparently brought mankind comfort and well-being, but it has also created new problems for humans including environmental pollution, widespread changes in world weather conditions, etc. fossil fuels cause numerous environmental pollutions. in other words, on the one hand poisonous gases enter the environment fo...

The energy crisis in recent years has led to the use of thermodynamic cycles that work based on renewable energies. Low-temperature cycles—such as organic cycles—are suitable strategies for the application of renewable energies. The present study proposes a novel cycle through the integration of a two-stage compression refrigeration cycle with a combined Rankine power and ejector refrigerat...

‎let $g$ be a graph with vertex set $v(g)$ and edge set $x(g)$ and consider the set $a={0,1}$‎. ‎a mapping $l:v(g)longrightarrow a$ is called binary vertex labeling of $g$ and $l(v)$ is called the label of the vertex $v$ under $l$‎. ‎in this paper we introduce a new kind of graph energy for the binary labeled graph‎, ‎the labeled graph energy $e_{l}(g)$‎. ‎it depends on the underlying graph $g$...

in this paper, an algorithm , based on genetics and auxiliary nodes, to reduce energy consumption in wireless sensor networks has been presented. in this research, by considering some parameters as energy and distance, a target function has been created, which is more optimum comparing to other methods. in this research cluster head is selected by genetic algorithm. in rawsn algorithm a new tec...

we have performed density functional theory (dft) calculations to investigate the properties of defect in arepresentative armchair model of silicon nanotubes (sints). to this aim, the structures of pristine and defective(5,5) sints have been optimized and the properties such as bond lengths, total energies, binding energies,.formation energies, gap energies, and dipole moments have been evaluat...