Advective disk paradigm of black hole accretion includes self-consistent formation of shocks and outflows from post-shock region. We apply this paradigm to understand rich variation of the light curve of the black hole candidate GRS1915+105. We propose that out of five possible fundamental states the black hole candidate GRS1915+105 moves around among three of them creating all possible observed

Stability parameters for stabilized methods in uids are suggested. The computation of the largest eigenvalue of a generalized eigenvalue problem replaces controversial de nitions of element diameters and inverse estimate constants, used heretofore to compute these stability parameters. The design is employed in the advective-di usive model, incompressible Navier-Stokes equations and the Stokes ...

We present an approach to determining the speed of wave-front solutions to reaction-transport processes. This method is more accurate than previous ones. This is explicitly shown for several cases of practical interest: (i) the anomalous diffusion reaction, (ii) reaction diffusion in an advective field, and (iii) time-delayed reaction diffusion. There is good agreement with the results of numer...

FLOTRAN is a ground water ̄ow and transport model developed in the past few years which takes advantage of recent advances in numerical methodology. FLOTRAN solves the governing equations for ̄ow and contaminant transport using Godunovmixed methods, in which a higher-order Godunov method is used to approximate the advective ̄ux, and a mixed ®nite element method is used for the dispersive transp...

The current state of science and engineering related to analyzing wetlands overlooks the importance of transpiration and risks data misinterpretation. In response, we developed hydrologic and mass budgets for agricultural wetlands using electrical conductivity (EC) as a natural conservative tracer. We developed simple differential equations that quantify evaporation and transpiration rates usin...

In numerical modeling of physical phenomena it is often necessary to solve the advective transport equation for positive definite scalar functions. Numerical schemes of secondor higher-order accuracy can produce negative values in the solution due to the dispersive ripples. Lower-order schemes, such as the donor cell or Lax-Friedrichs, or higher-order schemes with zeroth-order diffusion added p...

We present a numerical scheme, based on Godunov’s method (REA algorithm), for the variance of the solution of the 1D random linear transport equation, with homogeneous random velocity and random initial condition. We obtain the stability conditions of the method and we also show its consistency with a deterministic nonhomogeneous advective-diffusive equation, which means convergency. Numerical ...