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In this paper, a high-accuracy conservative difference scheme is presented for solving the space fractional Zakharov system, which preserves the original conservative properties. By virtue of the standard energy method and mathematical induction, it is shown that the proposed scheme possesses the convergence rates of O (τ 2 + h 4). Finally, numerical examples testify the effectiveness of the conservative difference scheme and demonstrate the correctness of theoretical results. In particular, the effects of the fractional order α and β on the solitary solution behaviours are shown clearly through many intuitionistic images. [ABSTRACT FROM AUTHOR]

A general class of multi-term nonlinear fractional initial value problems involving variable-order fractional derivatives are considered. Some sufficient conditions for the existence and uniqueness of exact solution are established. An hp-version spectral collocation method is presented for solving the problem in numerical frames. It employs the shifted Legendre-Gauss interpolations to conquer the influence of the nonlinear term and the variable-order derivatives. The most remarkable feature of the method is its capability to achieve higher accuracy by refining the mesh and/or increasing the degree of the polynomial. The rigorous error estimates are derived for the problem with smooth solutions on arbitrary meshes and weakly singular solutions on quasi-uniform meshes. Numerical results are given to support the theoretical conclusions. [ABSTRACT FROM AUTHOR]

Numerical methods preserving a conserved quantity for stochastic differential equations are considered. A class of discrete gradient methods based on the skew-gradient form is constructed, and the sufficient condition of convergence order 1 in the mean-square sense is given. Then a class of linear projection methods is constructed. The relationship of the two classes of methods for preserving a conserved quantity is proved, which is, the constructed linear projection methods can be considered as a subset of the constructed discrete gradient methods. Numerical experiments verify our theory and show the efficiency of proposed numerical methods. [ABSTRACT FROM AUTHOR]

In this paper, a compact alternating direction implicit (ADI) Crank-Nicolson difference scheme is proposed and analysed for the solution of two-dimensional time fractional subdiffusion equation. The Riemann-Liouville time fractional derivative is approximated by the weighted and shifted Grünwald difference operator and the spatial derivative is discretized by a fourth-order compact finite difference method. The stability and convergence of the difference scheme are discussed and theoretically proven by using the energy method. Finally, numerical experiments are carried out to show that the numerical results are in good agreement with the theoretical analysis. [ABSTRACT FROM AUTHOR]

This paper deals with dissipativity of the theoretical solutions and numerical solutions of a general class of advection-reaction-diffusion equations with both fixed and distributed delays. Some sufficient conditions for the dissipativity of the mentioned problems are given. It is shown that adaptations of linear θ-methods and one-leg θ-methods discussed in the present paper have the ability to preserve dissipativity of the underlying systems when . Finally, numerical experiment is presented to confirm the theoretical results. [ABSTRACT FROM AUTHOR]

In this paper, a semi-explicit scheme is constructed for the space-independent FitzHugh–Nagumo equation. Qualitative stability analysis shows that the semi-explicit scheme is dynamically consistent with the space independent equation. Then, the semi-explicit scheme is extended to construct a new finite difference scheme for the full FitzHugh–Nagumo equation in one- and two-space dimensions, respectively. According to the theory ofM-matrices, it is proved that these new schemes are able to preserve the positivity and boundedness of solutions of the corresponding equations for arbitrary step sizes. The consistency and numerical stability of these schemes is also analysed. Combined with the property of the strictly diagonally dominant matrix, the convergence of these schemes is established. Numerical experiments illustrate our results and display the advantages of our schemes in comparison to some other schemes. [ABSTRACT FROM AUTHOR]