‎in this paper‎, ‎we study a class of boundary value problem‎ ‎involving the p-laplacian oprator and singular nonlinearities‎. ‎we‎ ‎analyze the existence a critical parameter $lambda^{ast}$ such‎ ‎that the problem has least one solution for‎ ‎$lambdain(0,lambda^{ast})$ and no solution for‎ ‎$lambda>lambda^{ast}.$ we find lower bounds of critical‎ ‎parameter $lambda^{ast}$‎. ‎we use the method ...

in order to study the effect of drought stress and harvesting stages on quantitative and qualitative yields of coriander (coriandrum sativum l.) this experiment was conducted on split plot based on a randomized completely block design with 3 replications in torbat-e heydariyeh university, iran, during growing season of 2010-2011. treatments were drought stress (in three levels no stress: contro...

We establish the existence of multiple solutions for a nonvariational elliptic systems involving p(x)-Laplacian operator. The approach combines methods sub–supersolution and Leray–Schauder topological degree.

Assuming that a system of quasilinear equations of gradient type admits a strict supersolution and a strict subsolution, we show that it also admits a positive solution.

In this paper we investigate numerically positive solutions of the equation −Δu = λu+u with Dirichlet boundary condition in a boundary domain Ω for λ > 0 and 0 < q < 1 < p < 2∗, we will compute and visualize the range of λ, this problem achieves a numerical solution. Keywords—positive solutions; concave-convex; sub-supersolution method; pseudo arclength method.

forest cover is one of the most effective factors in reducing flooding in northern iran, so that in recent years the destruction, land use changing and uncontrolled harvesting of forest areas, has greatly increased the number and magnitude of floods. so far, there have been few studies on forest hydrology in iran, particularly the northern hyrcanian forests. this study examines the impact of a ...

We investigate the effect of constant and periodic harvesting on the Beverton-Holt model in a periodically fluctuating environment. We show that in a periodically fluctuating environment, periodic harvesting gives a better maximum sustainable yield compared to constant harvesting. However, if one can also fix the environment, then constant harvesting in a constant environment can be a better op...