On the combined Dirac–Einstein–Maxwell field equations

Regularized Combined Field Integral Equations

Many boundary integral equations for exterior boundary value problems for the Helmholtz equation suffer from a notorious instability for wave numbers related to interior resonances. The so-called combined field integral equations are not affected. However, if the boundary is not smooth, the traditional combined field integral equations for the exterior Dirichlet problem do not give rise to an L...

Coercive combined field integral equations

Solution of Flow Field Equations and Verification of Cavitation Problem on Spillway of the dam

The main objective of this paper is to formulate a mathematical model for finding flow field and cavitation problem on dam spillways. The Navier-Stokes Equation has been applied for the computation of pressure and velocity field, free water surface profiles and other parameters. Also, for increasing accuracy of the problem, viscosity effect has been considered. Because of internal flows the eff...

survey on the rule of the due & hindering relying on the sheikh ansaris ideas

قاعده مقتضی و مانع در متون فقهی کم و بیش مستند احکام قرار گرفته و مورد مناقشه فقهاء و اصولیین می باشد و مشهور معتقند مقتضی و مانع، قاعده نیست بلکه یکی از مسائل ذیل استصحاب است لذا نگارنده بر آن شد تا پیرامون این قاعده پژوهش جامعی انجام دهد. به عقیده ما مقتضی دارای حیثیت مستقلی است و هر گاه می گوییم مقتضی احراز شد یعنی با ماهیت مستقل خودش محرز گشته و قطعا اقتضاء خود را خواهد داشت مانند نکاح که ...

Generalized Combined Field Integral Equations for the Iterative Solution of the Three-dimensional Helmholtz Equation

This paper addresses the derivation of new second-kind Fredholm combined field integral equations for the Krylov iterative solution of tridimensional acoustic scattering problems by a smooth closed surface. These integral equations need the introduction of suitable tangential square-root operators to regularize the formulations. Existence and uniqueness occur for these formulations. They can be...