in this paper, we studied the numerical solution of nonlinear weakly singular volterra-fredholm integral equations by using the product integration method. also, we shall study the convergence behavior of a fully discrete version of a product integration method for numerical solution of the nonlinear volterra-fredholm integral equations. the reliability and efficiency of the proposed scheme are...

We use a multi-resolution analysis based on a wavelet transform to upscale a 3D fractured reservoir. This paper describes a 3D, single-phase, and black-oil geological model (GM) that is used to simulate naturally-fractured reservoirs. The absolute permeability and porosity of GM is upscaled by all the possible combinations of Haar, Bior1.3, and Db4 wavelets in three levels of coarsening. The ap...

A number of results relative to the complexity of terminological logics have recently appeared in the literature. Unfortunately, most of these results are “negative”, as they show that, in the logics they refer to, deciding subsumption is intractable. In this paper we show that computing subsumption is O(n2) in B∇ac〈ma\∀4N−, a logic obtained by adding the two operators atleast and atmost, which...

The paper presents the application of Control-Volume Finite Element (CVFE) method in simulation of multi-phase (water, oil, gas) flow through porous media. The numerical model developed using the CVFE method presents advantage in simulation of faulted reservoirs or simulation of complex geometry reservoir. Also, CVFE method can accurate represents the location of wells inside of reservoir, fact...

We have developed a very efficient numerical algorithm of the strong disorder renormalization group method to study the critical behaviour of the random transverse field Ising model, which is a prototype of random quantum magnets. With this algorithm we can renormalize an N-site cluster within a time NlogN, independently of the topology of the graph, and we went up to N ∼ 4 × 10(6). We have stu...

The propagation of surface waves in a fluid- saturated porous isotropic layer over a semi-infinite homogeneous elastic medium with an irregularity for free and rigid interfaces have been studied. The rectangular irregularity has been taken in the half-space. The dispersion equation for Love waves is derived by simple mathematical techniques followed by Fourier transformations.  It can be seen t...

In this paper we study the distributed and boundary optimal control of the Stokes equations in presence of pointwise control constraints. The analysis of the problems involve existence results, as well as necessary conditions and optimality systems. A primal-dual active set strategy is studied for the numerical solution of the problems. For the distributed case, global and local convergence res...

in this article, a numerical approximation to the solution of the newell-whitehead equation (nwe) and cauchy problem of ill-posed non-linear diffusion equation have been studied. the presented scheme is obtained by using the derivative of the cubic b-spline quasi-interpolation (bsqi) to approximate the spatial derivative of the dependent variable and first order forward difference to approximat...