a function $f:v(g)rightarrow {-1,0,1}$ is a {em minusdominating function} if for every vertex $vin v(g)$, $sum_{uinn[v]}f(u)ge 1$. a minus dominating function $f$ of $g$ is calleda {em global minus dominating function} if $f$ is also a minusdominating function of the complement $overline{g}$ of $g$. the{em global minus domination number} $gamma_{g}^-(g)$ of $g$ isdefined as $gamma_{g}^-(g)=min{...

the idea of “forcing” has long been used in many research fields, such as colorings, orientations, geodetics and dominating sets in graph theory, as well as latin squares, block designs and steiner systems in combinatorics (see [1] and the references therein). recently, the forcing on perfect matchings has been attracting more researchers attention. a forcing set of m is a subset of m contained...

Let $S= \{e_1,\,e_2‎, ‎\ldots,\,e_m\}$ be an ordered subset of edges of a connected graph $G$‎. ‎The edge $S$-representation of an edge set $M\subseteq E(G)$ with respect to $S$ is the‎ ‎vector $r_e(M|S) = (d_1,\,d_2,\ldots,\,d_m)$‎, ‎where $d_i=1$ if $e_i\in M$ and $d_i=0$‎ ‎otherwise‎, ‎for each $i\in\{1,\ldots‎ , ‎k\}$‎. ‎We say $S$ is a global forcing set for maximal matchings of $G$‎ ‎if $...

‎hepatitis b virus (hbv) infection is a major public health problem in the world today‎. ‎a mathematical model is formulated to describe the spread of hepatitis b‎, ‎which can be controlled by vaccination as well as treatment‎. ‎we study the dynamical behavior of the system with fixed control for both vaccination and treatment‎. ‎the results shows that the dynamics of the model is completely de...

We study the distribution of the nontrivial zeros of ideal class zeta functions associated to elements in the symmetric space of GLn over a number field. We establish asymptotics for the number of nontrivial zeros up to height T , and asymptotics for the distribution of the nontrivial zeros with respect to the critical line. We combine these results to study the mean value of the real parts of ...

The idea of “forcing” has long been used in many research fields, such as colorings, orientations, geodetics and dominating sets in graph theory, as well as Latin squares, block designs and Steiner systems in combinatorics (see [1] and the references therein). Recently, the forcing on perfect matchings has been attracting more researchers attention. A forcing set of M is a subset of M contained...

in this paper we study the dynamics of hepatitis b virus (hbv) infection under administration of a vaccine and treatment, where the disease is transmitted directly from the parents to the offspring  and also through contact with infective individuals. stability of the disease-free steady state is investigated. the basic reproductive rate, $r_0$, is derived. the results show that the dynamics of...