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20112025
most citedConvergence rate for a Gauss collocation method applied to constrained optimal control

27 citations · 62 across the 20 of their papers we have counts for

collaborators

20 papers

math.CA2025

Error bounds for the asymptotic expansions of the Jacobi polynomials

Xiao-Min Huang, Yu Lin, Xiang-Sheng Wang +1

This paper aims to derive explicit and computable error bounds for the asymptotic expansion of the Jacobi polynomials as their degree approaches infinity, using an integral method.…

math.CA2024

Orthogonal polynomials with periodic recurrence coefficients

Dan Dai, Mourad E. H. Ismail, Xiang-Sheng Wang

In this paper, we study a class of orthogonal polynomials defined by a three-term recurrence relation with periodic coefficients. We derive explicit formulas for the generating fun…

math.CA2024

Asymptotics, orthogonality relations and duality for the and -symmetric polynomials in the -Askey scheme

Howard S. Cohl, Roberto S. Costas-Santos, Xiang-Sheng Wang

In this survey we summarize the current state of known orthogonality relations for the and -symmetric and dual subfamilies of the Askey--Wilson polynomials in the -A…

math.NA2022

Optimized sparse approximate inverse smoothers for solving Laplacian linear systems

Yunhui He, Jun Liu, Xiang-Sheng Wang

In this paper we propose and analyze new efficient sparse approximate inverse (SPAI) smoothers for solving the two-dimensional (2D) and three-dimensional (3D) Laplacian linear syst…

math.NA2022

A Direct Parallel-in-Time Quasi-Boundary Value Method for Inverse Space-Dependent Source Problems

Yi Jiang, Jun Liu, Xiang-Sheng Wang

Inverse source problems arise often in real-world applications, such as localizing unknown groundwater contaminant sources. Being different from Tikhonov regularization, the quasi-…

math.AP2022

A PDE-ODE Coupled Spatio-Temporal Mathematical Model for Fire Blight During Bloom

Michael Pupulin, Xiang-Sheng Wang, Messoud A Efendiev +2

Fire blight is a bacterial plant disease that affects apple and pear trees. We present a mathematical model for its spread in an orchard during bloom. This is a PDE-ODE coupled sys…

math.CA2021

Error bounds for the asymptotic expansions of the Hermite polynomials

Wei Shi, Gergő Nemes, Xiang-Sheng Wang +1

In this paper, we present explicit and computable error bounds for the asymptotic expansions of the Hermite polynomials with Plancherel--Rotach scale. Three cases, depending on whe…

math.CA2021

Supercritical Hopf Bifurcation of Cooperative Predation

Srijana Ghimire, Xiang-Sheng Wang

In this work, we conduct a rigorous analysis on the dynamics of a predator-prey model with cooperative predation. From the root classification of an algebraic equation, we derive e…

math.NA2021

A well-conditioned direct PinT algorithm for first-and second-order evolutionary equations

Jun Liu, Xiang-Sheng Wang, Shu-Lin Wu +1

In this paper, we propose a direct parallel-in-time (PinT) algorithm for time-dependent problems with first- or second-order derivative. We use a second-order boundary value method…

math.CA2021

Bivariate Lagrange interpolation at the checkerboard nodes

Lihua Cao, Srijana Ghimire, Xiang-Sheng Wang

In this paper, we derive an explicit formula for the bivariate Lagrange basis polynomials of a general set of checkerboard nodes. This formula generalizes existing results of bivar…

q-bio.PE2020★ 1 cited

Optimal allocation of face masks during the COVID-19 pandemic: a case study of the first epidemic wave in the United States

Jun Liu, Xiang-Sheng Wang

In this paper, we propose a two-group SIR epidemic model to simulate the outcome of stay-at-home policy and wearing face masks during the first COVID-19 epidemic wave in the United…

math-ph2018★ 1 cited

Asymptotics of partition functions in a fermionic matrix model and of related -polynomials

Dan Dai, Mourad E. H. Ismail, Xiang-Sheng Wang

In this paper, we study asymptotics of the thermal partition function of a model of quantum mechanical fermions with matrix-like index structure and quartic interactions. This part…

math.NA2016★ 27 cited

Convergence rate for a Gauss collocation method applied to constrained optimal control

William W. Hager, Jun Liu, Subhashree Mohapatra +2

A local convergence rate is established for a Gauss orthogonal collocation method applied to optimal control problems with control constraints. If the Hamiltonian possesses a stron…

math.NA2016★ 27 cited

Convergence Rate for a Radau hp Collocation Method Applied to Constrained Optimal Control

William W. Hager, Hongyan Hou, Subhashree Mohapatra +1

For unconstrained control problems, a local convergence rate is established for an -method based on collocation at the Radau quadrature points in each mesh interval of the disc…

math.CA2014★ 5 cited

Uniform Asymptotics of Orthogonal Polynomials Arising from Coherent States

Dan Dai, Weiying Hu, Xiang-Sheng Wang

In this paper, we study a family of orthogonal polynomials arising from nonlinear coherent states in quantum optics. Based on the three-term recurrence relation only,…

math.HO2014

Calculating the day of the week: null-days algorithm

Xiang-Sheng Wang

In this paper, we propose a new algorithm of calculating the day of the week for any given century, year, month and day in Gregorian calendar. We provide two simple formulas to con…

math.CA2014

Plancherel-Rotach Asymptotics of Second-Order Difference Equations with Linear Coefficients

Xiang-Sheng Wang

In this paper, we provide a complete Plancherel-Rotach asymptotic analysis of polynomials that satisfy a second-order difference equation with linear coefficients. According to the…

math.AP2014

Traveling Wave Phenomena in a Kermack-McKendrick SIR model

Haiyan Wang, Xiang-Sheng Wang

We study the existence and nonexistence of traveling waves of general diffusive Kermack-McKendrick SIR models with standard incidence where the total population is not constant. Th…

math.CA2013

Plancherel-Rotach asymptotic expansion for some polynomials from indeterminate moment problems

Dan Dai, Mourad E. H. Ismail, Xiang-Sheng Wang

We study the Plancherel--Rotach asymptotics of four families of orthogonal polynomials, the Chen--Ismail polynomials, the Berg-Letessier-Valent polynomials, the Conrad--Flajolet po…

math.CA2011★ 1 cited

Global Asymptotics of the Meixner Polynomials

X. -S. Wang, R. Wong

Using the steepest descent method for oscillatory Riemann-Hilbert problems introduced by Deift and Zhou [Ann. Math. {\bf 137}(1993), 295-368], we derive asymptotic formulas for the…