in this paper, we solve a linear system of second-order boundary value problems by using the quadratic b-spline nite el- ement method (fem). the performance of the method is tested on one model problem. comparisons are made with both the analyti- cal solution and some recent results.the obtained numerical results show that the method is ecient.

in this paper, we solve the quadratic $alpha$-functional equations $2f(x) + 2f(y) = f(x + y) + alpha^{-2}f(alpha(x-y)); (0.1)$ where $alpha$ is a fixed non-archimedean number with $alpha^{-2}neq 3$. using the fixed point method and the direct method, we prove the hyers-ulam stability of the quadratic $alpha$-functional equation (0.1) in non-archimedean banach spaces.

The linear time-varying elastance theory is frequently used to describe the change in ventricular stiffness during the cardiac cycle. The concept assumes that all isochrones (i.e., curves that connect pressure-volume data occurring at the same time) are linear and have a common volume intercept. Of specific interest is the steepest isochrone, the end-systolic pressure-volume relationship (ESPVR...

If efficient asset prices follow continuous semi-martingales and are perfectly observed, their quadratic variation can be measured accurately from the sum of a large number of squared returns sampled over very finely spaced intervals, i.e., realized variance (Andersen et al., 2003, and Barndorff-Nielsen and Shephard, 2002). With the emergence of high-frequency data, it seems that we should be a...

Background: While COVID-19 epidemic has been spreading worldwide, its characteristics are still unclear. The development of good mathematical models for predicting prevalence and subsiding is strongly expected. curve shows how the increases subsides. This number persons found infected daily. To express this with a model, compartment model such as SIR used generally. However, parameter values th...

We prove the logarithmic convexity of certain quantities, which measure the quadratic exponential decay at infinity and within two characteristic hyperplanes of solutions of Schrödinger evolutions. As a consequence we obtain some uniqueness results that generalize (a weak form of) Hardy’s version of the uncertainty principle. We also obtain corresponding results for heat evolutions.

In this paper we derive some pointwise error estimates for the local discontinuous Galerkin (LDG) method for solving second-order elliptic problems in RN (N ≥ 2). Our results show that the pointwise errors of both the vector and scalar approximations of the LDG method are of the same order as those obtained in the L2 norm except for a logarithmic factor when the piecewise linear functions are u...

A special finite element method based on approximate component mode synthesis (ACMS) was introduced in [U. Hetmaniuk, R. Lehoucq, A special finite element method based on component mode synthesis, ESAIM: Mathematical Modelling and Numerical Analysis, 44 (2010), 401-420]. ACMS was developed for second order elliptic partial differential equations with rough or highly varying coefficients. Here, ...