Asymptotic Sampling Distribution for Polynomial Chaos Representation from Data: A Maximum Entropy and Fisher Information Approach
A procedure is presented for characterizing the asymptotic sampling distribution of estimators of the polynomial chaos (PC) coefficients of a second-order nonstationary and non-Gaussian random process by using a collection of observations. The random ...
Multilevel Adaptive Aggregation for Markov Chains, with Application to Web Ranking
A multilevel adaptive aggregation method for calculating the stationary probability vector of an irreducible stochastic matrix is described. The method is a special case of the adaptive smoothed aggregation and adaptive algebraic multigrid methods for ...
A Numerical Method for the Generalized Regularized Long Wave Equation Using a Reproducing Kernel Function
A new numerical method for solving the generalized regularized long wave equation is devised and analyzed. By using a reproducing kernel function, the numerical solution at each discrete time step is obtained by an explicit integral expression even ...
Factorization Techniques for Nodal Spectral Elements in Curved Domains
Spectral element methods on tetrahedra with symmetric collocation points can be accelerated by factorizing the discrete operators according to Hesthaven and Teng [SIAM J. Sci. Comput., 21 (2000), pp. 2352-2380]. While these authors focused on first-...
Balanced Incomplete Factorization
In this paper we present a new incomplete factorization of a square matrix into triangular factors in which we get standard $LU$ or $LDL^T$ factors (direct factors) and their inverses (inverse factors) at the same time. Algorithmically, we derive this ...
Mixed Multiscale Finite Element Methods for Stochastic Porous Media Flows
In this paper, we propose a stochastic mixed multiscale finite element method. The proposed method solves the stochastic porous media flow equation on the coarse grid using a set of precomputed basis functions. The precomputed basis functions are ...
Efficient Calculation of Bounds on Spectra of Hessian Matrices
We introduce a new method for the calculation of bounds on eigenvalues of Hessian matrices $\nabla^2 \varphi(x)$ of twice continuously differentiable functions $\varphi:U\subseteq\mathbb{R}^n\rightarrow \mathbb{R}$. The computational complexity of the ...
Transparent Boundary Conditions for Time-Dependent Problems
A new approach to derive transparent boundary conditions (TBCs) for dispersive wave, Schrödinger, heat, and drift-diffusion equations is presented. It relies on the pole condition and distinguishes between physically reasonable and unreasonable ...
Efficient Solution of Anisotropic Lattice Equations by the Recovery Method
In a recent paper, the authors introduced the recovery method (local energy matching principle) for solving large systems of lattice equations. The idea is to construct a partial differential equation along with a finite element discretization such that ...
BPCONT: An Auto Driver for the Continuation of Branch Points of Algebraic and Boundary-Value Problems
BPcont, a driver for the software package Auto for the numerical continuation of simple branch points of algebraic and boundary-value problems, is described in detail. Simple branch points are points in the continuation space where two solution branches ...
Exact de Rham Sequences of Spaces Defined on Macro-Elements in Two and Three Spatial Dimensions
This paper proposes new finite element spaces that can be constructed for agglomerates of standard elements that have certain regular structure. The main requirement is that the agglomerates share faces that have closed boundaries composed of 1-d edges. ...
Norm Preconditioners for Discontinuous Galerkin $hp$-Finite Element Methods
We consider a norm-preconditioning approach for the solution of discontinuous Galerkin finite element discretizations of second order partial differential equations with a nonnegative characteristic form. Our solution method is a norm-preconditioned ...
On the Time Splitting Spectral Method for the Complex Ginzburg-Landau Equation in the Large Time and Space Scale Limit
We are interested in the numerical approximation of the complex Ginzburg-Landau equation in the large time and space limit. There are two interesting regimes in this problem, one being the large space time limit, and one being the nonlinear Schrödinger ...
Energy-Consistent CoRotational Schemes for Frictional Contact Problems
In this paper, we consider the unilateral frictional contact problem of a hyperelastic body in the case of large displacements and small strains. In order to retain the linear elasticity framework, we decompose the deformation into a large global ...
A Fast Iterative Method for Eikonal Equations
In this paper we propose a novel computational technique to solve the Eikonal equation efficiently on parallel architectures. The proposed method manages the list of active nodes and iteratively updates the solutions on those nodes until they converge. ...
An Efficient and Robust Method for Simulating Two-Phase Gel Dynamics
We develop a computational method for simulating models of gel dynamics where the gel is described by two phases: a networked polymer and a fluid solvent. The models consist of transport equations for the two phases, two coupled momentum equations, and ...
The Aitken-Like Acceleration of the Schwarz Method on Nonuniform Cartesian Grids
In this paper, we present a family of domain decomposition based on an Aitken-like acceleration of the Schwarz method seen as an iterative procedure with a linear rate of convergence. This paper is a generalization of the method first introduced at the ...
A Positive Preserving High Order VFRoe Scheme for Shallow Water Equations: A Class of Relaxation Schemes
The VFRoe scheme has been recently introduced by Buffard, Gallouët, and Hérard [Comput. Fluids, 29 (2000), pp. 813-847] to approximate the solutions of the shallow water equations. One of the main interests of this method is to be easily implemented. As ...
Postprocessing of the Linear Sampling Method by Means of Deformable Models
The linear sampling method is a qualitative procedure for the visualization of both impenetrable and inhomogeneous scatterers, which requires the regularized solution of a linear ill-posed integral equation of the first kind. An open issue in this ...
Constructing Sobol Sequences with Better Two-Dimensional Projections
Direction numbers for generating Sobol$'$ sequences that satisfy the so-called Property A in up to 1111 dimensions have previously been given in Joe and Kuo [ACM Trans. Math. Software, 29 (2003), pp. 49-57]. However, these Sobol$'$ sequences may have ...
Iterative Algorithms Based on Decoupling of Deblurring and Denoising for Image Restoration
In this paper, we propose iterative algorithms for solving image restoration problems. The iterative algorithms are based on decoupling of deblurring and denoising steps in the restoration process. In the deblurring step, an efficient deblurring method ...
Bottom-Up Construction and 2:1 Balance Refinement of Linear Octrees in Parallel
In this article, we propose new parallel algorithms for the construction and 2:1 balance refinement of large linear octrees on distributed memory machines. Such octrees are used in many problems in computational science and engineering, e.g., object ...