A matching M of a graph G is maximal if it not proper subset any other in G. Maximal matchings are much less known and researched than their maximum perfect counterparts. In this paper we present the recurrences generating functions for sequences enumerating two classes chemically interesting linear polymers: polyspiro chains benzenoid chains. We also analyze asymptotic behavior those determine...

We study the critical and off-critical ~Griffiths-McCoy! regions of the random transverse-field Ising spin chain by analytical and numerical methods and by phenomenological scaling considerations. Here we extend previous investigations to surface quantities and to the ferromagnetic phase. The surface magnetization of the model is shown to be related to the surviving probability of an adsorbing ...

Zagreb indices belong to better known and better researched topological indices. We investigate here their ability to discriminate among benzenoid graphs and arrive at some quite unexpected conclusions. Along the way we establish tight (and sometimes sharp) lower and upper bounds on various classes of benzenoids.

The edge version of Szeged index and vertex version of PI index are defined very recently. They are similar to edge-PI and vertex-Szeged indices, respectively. The different versions of Szeged and PIindices are the most important topological indices defined in Chemistry. In this paper, we compute the edge-Szeged and vertex-PIindices of some important classes of benzenoid systems.

objective(s) resistance to antimicrobial agents, particularly metronidazole and clarithromycin, is frequently observed in helicobacter pylori and may be associated with treatment failure. this resistance rate varies according to the population studied. the aim of this study was to assess the pattern of antimicrobial resistance of h. pylori isolates from dyspeptic patients in isfahan. materials ...

due to business and environmental issues, the efficient design of an integrated forward/reverse logistics network has recently attracted more attention from researchers. the significance of transportation cost and customer satisfaction spurs an interest in developing a flexible network design model with different delivery paths. this paper proposes a flexible mixed-integer programming model to ...

In this paper, the two parameter ADK entropy, as a generalized of Re'nyi entropy, is considered and some properties of it, are investigated. We will see that the ADK entropy for continuous random variables is invariant under a location and is not invariant under a scale transformation of the random variable. Furthermore, the joint ADK entropy, conditional ADK entropy, and chain rule of this ent...