The error generated by the classical upwind finite difference method on a uniform mesh, when applied to a class of singularly perturbed model ordinary differential equations with a singularly perturbed Neumann boundary condition, tends to infinity as the singular perturbation parameter tends to zero. Note that the exact solution is uniformly bounded with respect to the perturbation parameter. F...

It is important to simulate a groundwater transport process, e.g., pollutant migration, through the vadose zone and subsequent mixing within the saturated zone to assess potential impacts of contaminants in the subsurface in preliminary stages. It is challenging to simulate heterogeneous soil characteristics and non-uniform initial contaminant concentration. This paper proposes a vertically het...

The results of computations with eight explicit finite difference schemes on a suite of one-dimensional and two-dimensional test problems for the Euler equations are presented in various formats. Both dimensionally split and two-dimensional schemes are represented, as are central and upwind-biased methods, and all are at least second-order accurate.

in this paper, we consider first-order fuzzy differential equations with initial value conditions. the convergence, consistency and stability of difference method for approximating the solution of fuzzy differential equations involving generalized h-differentiability, are studied. then the local truncation error is defined and sufficient conditions for convergence, consistency and stability of ...

Background Helicobacter pylori (H. pylori) is believed to be the most common bacterial infection worldwide. Herein, we aimed to investigate the effect of red rose extract on H. pylori eradication in 9 to 15 year-old children. Materials and Methods In this randomized controlled clinical trial,by the convenience sampling method...

What are the conditions for fixing the reference of a proper name? Debate on this point has recently been rekindled by Scott Soames, Robin Jeshion, and others. In this paper, I sketch a new pragmatic approach to the justification of reference-fixing procedures, in opposition to accounts that insist on an invariant set of conditions for fixing reference across environments and linguistic communi...

we have recently synthesized [ni (map) ] complex [h-map= 2- (methylamino) pyridine]. 2- (methy1amino)pyridine reacts with meli in thf and generates the lithium salt (li-map). further reaction of nicl with two equivalent of this ligand in thf leads to the formation of a dark red solution. analytical data, molecular weight, and magnetic susceptibility of this complex confirm the formula [ni (map)...

background: the present study examined the possible role of endogenous opioidergic system in effect of food deprivation on formalin-induced nociceptive behaviors in male and female rats. also, we investigated the effect of food deprivation on the plasma level of beta-endorphin and sex hormones. methods: food was withdrawn 48 h prior to performing the formalin test, but water continued to be ava...