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This paper presents a comprehensive survey of methods which can be utilized to search for solutions to systems of nonlinear equations (SNEs). Our objectives with this survey are to synthesize pertinent literature in this field by presenting…

Mathematical Software · Computer Science 2022-08-19 Ilias S. Kotsireas , Panos M. Pardalos , Alexander Semenov , William T. Trevena , Michael N. Vrahatis

We propose a systemic method of applying the auxiliary systems of original equations to find the high order nonlocal symmetries of nonlinear evolution equation. In order to validate the effectiveness of the method, some examples are…

Exactly Solvable and Integrable Systems · Physics 2012-12-27 Xiangpeng Xin , Yong Chen

We study and derive algorithms for nonlinear eigenvalue problems, where the system matrix depends on the eigenvector, or several eigenvectors (or their corresponding invariant subspace). The algorithms are derived from an implicit…

Numerical Analysis · Mathematics 2020-03-02 Elias Jarlebring , Parikshit Upadhyaya

When a physical system is modeled by a nonlinear function, the unknown parameters can be estimated by fitting experimental observations by a least-squares approach. Newton's method and its variants are often used to solve problems of this…

Numerical Analysis · Mathematics 2021-09-20 Federica Pes , Giuseppe Rodriguez

We provide the classical Boundary Harnack principle in Lipschitz domains for solutions to two different linear uniformly elliptic equations with the same principal part.

Analysis of PDEs · Mathematics 2025-07-04 Daniela De Silva , Ovidiu Savin

We prove some new results on existence of solutions to first--order ordinary differential equations with deviating arguments. Delay differential equations are included in our general framework, which even allows deviations to depend on the…

Classical Analysis and ODEs · Mathematics 2014-02-26 Rubén Figueroa , Rodrigo López Pouso

We study the existence of positive solutions on the half-line of a second order ordinary differential equation subject to functional boundary conditions. Our approach relies on a combination between the fixed point index for operators on…

Classical Analysis and ODEs · Mathematics 2021-03-29 Gennaro Infante , Serena Matucci

We look at the number of solutions of an equation of the form f_1*f_2*...*f_k=a in a finite field, where each f_i is a multilinear polynomial. We use two methods to construct a solution of this problem for the cases a=0, a<>0, and we…

Number Theory · Mathematics 2007-05-23 T. Narayaninsamy , D. -J. Mercier , J. -P. Cherdieu

This article generalizes a recently introduced procedure to solve nonlinear systems of equations, radically departing from the conventional Newton-Raphson scheme. The original nonlinear system is first unfolded into three simpler…

Numerical Analysis · Mathematics 2014-07-24 Antonio Gómez-Expósito

In this paper we analyze a class of nonconvex optimization problem from the viewpoint of abstract convexity. Using the respective generalizations of the subgradient we propose an abstract notion proximal operator and derive a number of…

Optimization and Control · Mathematics 2024-02-29 Ewa Bednarczuk , Dirk Lorenz , The Hung Tran

We suggest a direct algorithm for searching the Lax pairs for nonlinear integrable equations. It is effective for both continuous and discrete models. The first operator of the Lax pair corresponding to a given nonlinear equation is found…

Exactly Solvable and Integrable Systems · Physics 2016-01-12 I. T. Habibullin , A. R. Khakimova , M. N. Poptsova

We introduce a constructive method that provides the local solution of general implicit systems in arbitrary dimension via Hamiltonian type equations. A variant of this approach constructs parametrizations of the manifold, extending the…

Classical Analysis and ODEs · Mathematics 2019-09-18 Dan Tiba

In the present paper, we obtain some gradient estimates for positive solutions to the following nonlinear parabolic equation under general geometric flow on complete noncompact manifolds.

Differential Geometry · Mathematics 2019-01-15 Gh. Fasihi Ramandi , S. Azami

In this paper, using the similarity method, we construct particular solutions with singularities for degenerate high-order equations. The considered equations have singularities of the first and second kind. Particular solutions are…

Analysis of PDEs · Mathematics 2020-05-06 B. Yu. Irgashev

This paper presents a method for constructing flat deformations of associative algebras. We will refer to this method as method two because it is a generalisation of the method obtained in [1]. The deformations obtained using the first two…

Rings and Algebras · Mathematics 2025-07-08 Agata Smoktunowicz

We propose a general dual ascent framework for Lagrangean decomposition of combinatorial problems. Although methods of this type have shown their efficiency for a number of problems, so far there was no general algorithm applicable to…

Data Structures and Algorithms · Computer Science 2017-01-13 Paul Swoboda , Jan Kuske , Bogdan Savchynskyy

We study the optimal approximation of the solution of an operator equation Au=f by linear and nonlinear mappings. We identify those cases where optimal nonlinear approximation is better than optimal linear approximation.

Numerical Analysis · Mathematics 2025-10-20 Stephan Dahlke , Erich Novak , Winfried Sickel

Existence, regularity and location of solutions to quasilinear singular elliptic systems with general gradient dependence are established developing a method of sub-supersolution. The abstract theorems involving sub-supersolutions are…

Analysis of PDEs · Mathematics 2025-08-11 Abdelkrim Moussaoui

A three-point iterative method for solving scalar non-linear equations was selected and then adapted to solve systems of non-linear equations. Subsequently, by applying Taylor's theorem to functions of $\R^{n}$ in $\R^{n}$, it is shown that…

General Mathematics · Mathematics 2026-01-23 Carlos E. Cadenas R. , Yorman J. Mendoza N

A nonlinear operator equation $F(x)=0$, $F:H\to H,$ in a Hilbert space is considered. Continuous Newton's-type procedures based on a construction of a dynamical system with the trajectory starting at some initial point $x_0$ and becoming…

Numerical Analysis · Mathematics 2025-10-20 A. G. Ramm , A. B. Smirnova , A. Favini