Analysis of Inhibitory Effects of Mixed Biogas Slurry-pesticide Formulation against Alternaria solani Sorauer

[Objective] The paper was to explore the inhibitory effect of mixed biogas slurry-pesticide formulation against Alternaria solani Sorauer. [Method] Different concentrations of Triadimefon, Hekang, Yibao, Propamocarb hydrochloride and Jinggangmycin were mixed with biogas slurry, and their inhibitory effects were determined by the methods of mycelial inhibition and spore germination. [Result] Mycelial inhibition study showed that mixed formulation of Propamocarb hydrochloride owned the highest inhibition efficiency, and its EC50 value was 3 mg/L. For spore germination, the inhibitory effects of the tested formulations were almost the same as CK, but Hekang and Jinggangmycin had relatively stronger inhibitory effect. The inhibitory effect of mixed formulations with water as solvent was significant. Five kinds of agro-chemicals mixed with biogas slurry had much stronger inhibition effect against the growth of mycelium than that on spore germination. [Conclusion] This study laid foundations for the development of neo-pesticide.

A STABILIZED MIXED FINITE ELEMENT FORMULATION FOR THE NON-STATIONARY INCOMPRESSIBLE BOUSSINESQ EQUATIONS

In this study, we employ mixed finite element （MFE） method, two local Gauss integrals, and parameter-free to establish a stabilized MFE formulation for the non-stationary incompressible Boussinesq equations. We also provide the theoretical analysis of the existence, uniqueness, stability, and convergence of the stabilized MFE solutions for the stabilized MFE formulation.

A STABILIZED CRANK-NICOLSON MIXED FINITE VOLUME ELEMENT FORMULATION FOR THE NON-STATIONARY PARABOLIZED NAVIER-STOKES EQUATIONS

A time semi-discrete Crank-Nicolson （CN） formulation with second-order time accuracy for the non-stationary parabolized Navier-Stokes equations is firstly established. And then, a fully discrete stabilized CN mixed finite volume element （SCNMFVE） formu- lation based on two local Gaussian integrals and parameter-free with the second-order time accuracy is established directly from the time semi-discrete CN formulation so that it could avoid the discussion for semi-discrete SCNMFVE formulation with respect to spatial wriables and its theoretical analysis becomes very simple. Finally, the error estimates of SCNMFVE solutions are provided.

A MIXED VARIATIONAL FORMULATION FOR LARGE DEFORMATION ANALYSIS OF PLATES

A mixed vuriational formulation for large deformation analysis of plates is introduced. In this formulation the equilibrium ami compatibility equations are satisfied identically by means of stress functions and displacement components, respectively, and the constitu,lye equations are satisfied in a least square sense. An example is solved and the results are compared with those available in the literature.Further, the functional is particularized for buckling analysis of plates and a simple example is solved to illustrate the theory.

A REDUCED MFE FORMULATION BASED ON POD FOR THE NON-STATIONARY CONDUCTION-CONVECTION PROBLEMS

In this article, a reduced mixed finite element （MFE） formulation based on proper orthogonal decomposition （POD） for the non-stationary conduction-convection problems is presented. Also the error estimates between the reduced MFE solutions based on POD and usual MFE solutions are derived. It is shown by numerical examples that the results of numerical computation are consistent with theoretical conclusions. Moreover, it is shown that the reduced MFE formulation based on POD is feasible and efficient in finding numerical solutions for the non-stationary conduction-convection problems.

A REDUCED-ORDER MFE FORMULATION BASED ON POD METHOD FOR PARABOLIC EQUATIONS

In this paper, we extend the applications of proper orthogonal decomposition （POD） method, i.e., apply POD method to a mixed finite element （MFE） formulation naturally satisfied Brezz-Babu^ka for parabolic equations, establish a reduced-order MFE formulation with lower dimensions and sufficiently high accuracy, and provide the error estimates between the reduced-order POD MFE solutions and the classical MFE solutions and the implementation of algorithm for solving reduced-order MFE formulation. Some numerical examples illustrate the fact that the results of numerical computation are consis- tent with theoretical conclusions. Moreover, it is shown that the new reduced-order MFE formulation based on POD method is feasible and efficient for solving MFE formulation for parabolic equations.

AN EFFICIENT ITERATION ALGORITHM OF MIXED BOUNDARY/FINITE ELEMENT METHOD AND APPLICATION TO FREE TORSIONAL VIBRATION ANALYSIS OF BODIES OF REVOLUTION

In this paper, the general formulation of anew proposed iteration algorithm of mixed BEM/FEM for eigenvalue problems of elastodynamics is described. Approximate fundamental solutions of elastodynamics are adopted in the normal mixed BEM/FEM equations. The accuracy of solutions is progressively improved by the iteration procedure. Not only could the awkwardness of non-algebraic eigenvalue equations be avoided but also the accuracy of numerical solutions is almost independent of the interior meshing. All these give many advantages in numerical calculation. The algorithm is applied to free torsional vibration analysis of bodies of revolution. A few cases are studied. All of the numerical results are very good.

A POD REDUCED-ORDER SPDMFE EXTRAPOLATING ALGORITHM FOR HYPERBOLIC EQUATIONS

In this article, a proper orthogonal decomposition （POD） method is used to study a classical splitting positive definite mixed finite element （SPDMFE） formulation for second- order hyperbolic equations. A POD reduced-order SPDMFE extrapolating algorithm with lower dimensions and sufficiently high accuracy is established for second-order hyperbolic equations. The error estimates between the classical SPDMFE solutions and the reduced-order SPDMFE solutions obtained from the POD reduced-order SPDMFE extrapolating algorithm are provided. The implementation for solving the POD reduced-order SPDMFE extrapolating algorithm is given. Some numerical experiments are presented illustrating that the results of numerical computation are consistent with theoretical conclusions, thus validating that the POD reduced-order SPDMFE extrapolating algorithm is feasible and efficient for solving second-order hyperbolic equations.

A Weak Galerkin Mixed Finite Element Method for Second Order Elliptic Equations on 2D Curved Domains

This article concerns the weak Galerkin mixed finite element method(WGMFEM)for second order elliptic equations on 2D domains with curved boundary.The Neumann boundary condition is considered since it becomes the essential boundary condition in this case.It is well-known that the discrepancy between the curved physical domain and the polygonal approximation domain leads to a loss of accuracy for discretizationwith polynomial order a>1.The purpose of this paper is two-fold.First,we present a detailed error analysis of the original WG-MFEM for solving problems on curved domains,which exhibits an O(h^(1/2))convergence for all a≥1.It is a little surprising to see that even the lowest-order WG-MFEM(a=1)experiences a loss of accuracy.This is different from known results for the finite element method(FEM)or the mixed FEM,and appears to be a combined effect of the WG-MFEM design and the fact that the outward normal vector on the polygonal approximation domain is different from the one on the curved domain.Second,we propose a remedy to bring the approximation rate back to optimal by employing two techniques.One is a specially designed boundary correction technique.The other is to take full advantage of the nice feature that weak Galerkin discretization can be defined on polygonal meshes,which allows the curved boundary to be better approximated by multiple short edges without increasing the total number of mesh elements.Rigorous analysis shows that a combination of the above two techniques renders optimal convergence for all a.Numerical results further confirm this conclusion.

A Stabilized Crank-Nicolson Mixed Finite Element Method for Non-stationary Parabolized Navier-Stokes Equations

In this study, a time semi-discrete Crank-Nicolson （CN） formulation with second-order time accu- racy for the non-stationary parabolized Navier-Stokes equations is firstly established. And then, a fully discrete stabilized CN mixed finite element （SCNMFE） formulation based on two local Gauss integrals and parameter- free with the second-order time accuracy is established directly from the time semi-discrete CN formulation. Thus, it could avoid the discussion for semi-discrete SCNMFE formulation with respect to spatial variables and its theoretical analysis becomes very simple. Finaly, the error estimates of SCNMFE solutions are provided.

AN ENHANCED ELEMENT-FREE GALERKIN METHOD FOR DYNAMIC RESPONSE OF POROELASTIC SEABED

This study presents an effective numerical model for the dynamic response of poroelastic seabed under wave action with enhanced performance. The spatial discretization is based on the Element-Free Galerkin （EFG） method and the time integration based on the GN11 scheme. A stability strategy that adopts a smaller number of nodes for the pore water pressure compared with those for the displacements of the soil skeleton is suggested to resolve the similar difficulty as encountered in the finite element method for a problem with mixed formulation when the pore water is incompressible and the soil skeleton impervious. The accuracy of the numerical model is verified through applying it to a typical case with critical permeability. Good agreement between computational and analytical solutions is obtained.