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The two-stage meshless method utilizing the method of particular and fundamental solutions two-stage MPS–MFS was originally proposed to solve steady-state boundary value problems. Despite its great success in handling complicated irregular domains, when applied as a spatial discretization technique to solve time-dependent problems, especially for hyperbolic PDEs, the two-stage MPS–MFS seems to lead to numerical stability issues for conventional time-marching schemes. In addition to the unstable phenomena observed in some existing works, a concrete example on wave equation in this paper also shows the instability of this methodology, even though the utilized time-marching schemes are unconditionally stable. To investigate and explain this instability, we intend to conduct a thorough analysis of the time-marching MPS–MFS method for wave equations. To our best knowledge, this is the first time that the stability issue of the MPS–MFS methodology for hyperbolic PDEs is studied. To compensate for the instability caused by the two-stage MPS–MFS, we also propose a novel time-marching meshless method by combining the method of polynomial particular solutions (MPPS) and the Rothe’s method. This innovative method has a distinct solution mechanism and outperforms the time-marching MPS–MFS method in terms of stability and accuracy. Numerical results are provided to support our findings.

The method of fundamental solutions is coupled with the boundary control technique to solve the Cauchy problems of the Laplace Equations. The main idea of the proposed method is to solve a sequence of direct problems instead of solving the inverse problem directly. In particular, we use a boundary control technique to obtain an approximation of the missing Dirichlet boundary data; the Tikhonov regularization technique and the L-curve method are employed to achieve such goal stably. Once the boundary data on the whole boundary are known, the numerical solution to the Cauchy problem can be obtained by solving a direct problem. Numerical examples are provided for verifications of the proposed method on the steady-state heat conduction problems.

In this paper we investigate the application of the localized method of fundamental solutions (LMFS) for solving three-dimensional inhomogeneous elliptic boundary value problems. A direct Chebyshev collocation scheme (CCS) is employed for the approximation of the particular solutions of the given inhomogeneous problem. The Gauss–Lobatto collocation points are used in the CCS to ensure the pseudo-spectral convergence of the method. The resulting homogeneous equations are then calculated by using the LMFS. In the framework of the LMFS, the computational domain is divided into a set of overlapping local subdomains where the traditional MFS formulation and the moving least square method are applied. The proposed CCS-LMFS produces sparse and banded stiffness matrix which makes the method possible to perform large-scale simulations on a desktop computer. Numerical examples involving Poisson, Helmholtz as well as modified-Helmholtz equations (with up to 1,000,000 unknowns) are presented to illustrate the efficiency and accuracy of the proposed method.

Analytical particular solutions of Chebyshev polynomials are obtained for problems of Reissner plates under arbitrary loadings, which are governed by three coupled second-ordered partial differential equation (PDEs). Our solutions can be written explicitly in terms of monomials. By using these formulas, we can obtain the approximate particular solution when the arbitrary loadings have been represented by a truncated series of Chebyshev polynomials. In the derivations of particular solutions, the three coupled second-ordered PDE are first transformed into a single six-ordered PDE through the Hörmander operator decomposition technique. Then the particular solutions of this six-ordered PDE can be found in the author's previous study. These formulas are further implemented to solve problems of Reissner plates under arbitrary loadings in which the homogeneous solutions are complementarily solved by the method of fundamental solutions (MFS). Numerical experiments are carried out to validate these particular solutions. Due to the exponential convergence of both Chebyshev interpolation and the MFS, our numerical results are extremely accurate.

This paper deals with the numerical approximation of solutions of Stokes and Brinkman systems using meshless methods. The aim is to solve a problem containing a nonzero body force, starting from the well known decomposition in terms of a particular solution and the solution of a homogeneous force problem. We propose two methods for the numerical construction of a particular solution. One method is based on the Neuber-Papkovich potentials, which we extend to nonhomogeneous Brinkman problems. A second method relies on a Helmholtz-type decomposition for the body force and enables the construction of divergence-free basis functions. Such basis functions are obtained from Hänkel functions and justified by new density results for the space H1(Ω). Several 2D numerical experiments are presented in order to discuss the feasibility and accuracy of both methods.

The method of particular solutions (MPS) has been widely applied for solving various types of partial differential equations. In this paper, the space–time collocation technique is implemented using MPS with polynomial basis functions (MPS-PBF) to solve the nonlinear Fisher–KPP (Kolmogorov–Petrovsky–Piskunov) equation in both one and two dimensions. The Picard iteration method is used to deal with the nonlinearity of the problem. Four numerical examples are provided, and their results are compared with established methods to demonstrate the effectiveness of the proposed scheme.

In this paper, a new extended (3+1)-dimensional shallow water wave equation is discussed via Lie symmetry analysis. Making use of symmetric nodes, we obtain two kinds of symmetrically reduced ODEs. By means of power series, we obtain the two kinds of exact power series solutions. By invoking a new conservation theorem of Ibragimov, the conservation laws are constructed.

In this paper, the method of polynomial particular solutions is used to solve nonlinear Poisson-type partial differential equations in one, two, and three dimensions. The condition number of the coefficient matrix is reduced through the implementation of multiple scale technique, ultimately yielding a stable numerical solution. The methodological process can be divided into two main parts: first, identifying the corresponding polynomial particular solutions for the linear differential operator terms in the governing equations, and second, employing these polynomial particular solutions as basis function to iteratively solve the remaining nonlinear terms within the governing equations. Additionally, we investigate the potential improvement in numerical accuracy for equations with singularities in the analytical solution by shifting the computational domain a certain distance. Numerical experiments are conducted to assess both the accuracy and stability of the proposed method. A comparison of the obtained results with those produced by other numerical methods demonstrates the accuracy, stability, and efficiency of the proposed method in handling nonlinear Poisson-type partial differential equations.

We numerically compute the lowest Laplacian eigenvalues of several two-dimensional shapes with dihedral symmetry at arbitrary precision arithmetic. Our approach is based on the method of particular solutions with domain decomposition. We are particularly interested in asymptotic expansions of the eigenvalues λ ( n ) of shapes with n edges that are of the form λ ( n ) ∼ x ∑ k = 0 ∞ C k ( x ) n k where x is the limiting eigenvalue for n → ∞ . Expansions of this form have previously only been known for regular polygons with Dirichlet boundary conditions and (quite surprisingly) involve Riemann zeta values and single-valued multiple zeta values, which makes them interesting to study. We provide numerical evidence for closed-form expressions of higher order C k ( x ) and give more examples of shapes for which such expansions are possible (including regular polygons with Neumann boundary condition, regular star polygons, and star shapes with sinusoidal boundary).

In this paper, a new class of extended (2+1)-dimensional Ito equations is investigated for its group invariant solutions. The Lie symmetry method is employed to transform the nonlinear Ito equation into an ordinary differential equation. The general solution of the solvable linear differential equation with different parameters is obtained, and the plot of the solvable linear differential equation is given. A power series solution for the equation is then derived. Furthermore, a conservation law for the equation is constructed by utilizing a new Ibragimov conservation theorem.