In this paper, a positive definite semi-discrete mixed finite element method was presented for two-dimensional parabolic equations. In the new positive definite systems, the gradient equation and flux equations were separated from their scalar unknown equations.  Also, the existence and uniqueness of the semi-discrete mixed finite element solutions were proven. Error estimates were also obtaine...

Stability and convergence analyses for the domain decomposition finite element/finite difference (FE/FD) method are presented. The developed a semi-discrete element scheme time-dependent Maxwell’s equations. explicit schemes in different settings of spatial constructed algorithm is formulated. Several numerical examples validate rates obtained theoretical studies.

this paper is about discrete sensitivity analysis. a triangular bending element with constant moment and six degrees of freedom is used. the required derivatives for sensitivity analysis are calculated explicitly. these formulations, finite element method and sequential linear programming are utilized to find shape optimization of plate bending structures. the numerical examples, which show the...

An explicit fully discrete finite element method, which satisfies the nonconvex side constraint at every node, is developed for approximating the p-harmonic flow for p ∈ (1,∞). Convergence of the method is established under certain conditions on the domain and mesh. Computational examples are presented to demonstrate finite-time blow-ups and qualitative geometric changes of weak solutions of th...

in this article, the discrete time state space model with first-order autoregressive dependent process noise is considered and the recursive method for filtering, prediction and smoothing of the hidden state from the noisy observation is designed. the explicit solution is obtained for the hidden state estimation problem. finally, in a simulation study, the performance of the designed method ...

Oil production may be accompanied by Sand Production (SP) in the weak sandstone reservoirs. Fluid flow is an important factor in transporting the separated grains and completing the SP mechanism. In this paper, the effect of fluid parameters, fluid flow, and fluid pressure on the SP is investigated by applying the Discrete Element Method (DEM). Parametric studies show that fluid velocity is red...

Rock slope stability depends very much on the strength features of the rock and the geometrical and strength characteristics of the discontinuities (e.g., roughness, wall strength and persistence). Since a rock mass is not a continuum, its behavior is dominated by such discontinuities as faults, joints and bedding planes. Also, Rock slope instability is a major hazard for human activities and o...