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82 Results Found

  • Article
  • Open Access
999 Views
22 Pages

4 December 2024

In this paper, we deal with the properties and applications of a nonlinear scalarization function for sets by using the Minkowski difference. Under some suitable assumptions, the continuity and convexity concerned with the nonlinear scalarization fun...

  • Article
  • Open Access
4 Citations
3,013 Views
19 Pages

A Spherical Volume-Rendering Method of Ocean Scalar Data Based on Adaptive Ray Casting

  • Weijie Li,
  • Changxia Liang,
  • Fan Yang,
  • Bo Ai,
  • Qingtong Shi and
  • Guannan Lv

There are some limitations in traditional ocean scalar field visualization methods, such as inaccurate expression and low efficiency in the three-dimensional digital Earth environment. This paper presents a spherical volume-rendering method based on...

  • Article
  • Open Access
1 Citations
3,195 Views
17 Pages

20 January 2020

This paper explores new notions of approximate minimality in set optimization using a set approach. We propose characterizations of several approximate minimal elements of families of sets in real linear spaces by means of general functionals, which...

  • Article
  • Open Access
3 Citations
2,114 Views
11 Pages

2 September 2019

In this paper, we introduce the new concepts of K-adjustability convexity and strictly K-adjustability convexity which respectively generalize and extend the concepts of K-convexity and strictly K-convexity. We establish some new existence and unique...

  • Article
  • Open Access
2 Citations
3,186 Views
24 Pages

28 January 2022

Motivated by mobile devices that record data at a high frequency, we propose a new methodological framework for analyzing a semi-parametric regression model that allow us to study a nonlinear relationship between a scalar response and multiple functi...

  • Article
  • Open Access
16 Citations
2,089 Views
18 Pages

13 November 2022

In this article, a scalar nonlinear integro-differential equation of second order and a non-linear system of integro-differential equations with infinite delays are considered. Qualitative properties of solutions called the global asymptotic stabilit...

  • Article
  • Open Access
8 Citations
3,121 Views
17 Pages

There is no doubt that there is plethora of optimal fourth-order iterative approaches available to estimate the simple zeros of nonlinear functions. We can extend these method/methods for multiple zeros but the main issue is to preserve the same conv...

  • Article
  • Open Access
11 Citations
3,433 Views
18 Pages

New Conservation Laws and Exact Cosmological Solutions in Brans–Dicke Cosmology with an Extra Scalar Field

  • Antonios Mitsopoulos,
  • Michael Tsamparlis,
  • Genly Leon and
  • Andronikos Paliathanasis

27 July 2021

The derivation of conservation laws and invariant functions is an essential procedure for the investigation of nonlinear dynamical systems. In this study, we consider a two-field cosmological model with scalar fields defined in the Jordan frame. In p...

  • Article
  • Open Access
408 Views
10 Pages

24 November 2025

In this work, we discuss the conditions that allow the establishment of an equivalence between f(R,T)=R+λh(T) gravity models and General Relativity (GR) coupled to a modified matter sector. We do so by considering a D-dimensional spacetime and...

  • Article
  • Open Access
9 Citations
3,300 Views
14 Pages

A New Three-Step Class of Iterative Methods for Solving Nonlinear Systems

  • Raudys R. Capdevila,
  • Alicia Cordero and
  • Juan R. Torregrosa

11 December 2019

In this work, a new class of iterative methods for solving nonlinear equations is presented and also its extension for nonlinear systems of equations. This family is developed by using a scalar and matrix weight function procedure, respectively, gett...

  • Article
  • Open Access
8 Citations
1,857 Views
15 Pages

30 December 2022

In this article, a class of scalar nonlinear integro-differential equations of first order with fading memory is investigated. For the considered fading memory problem, we discuss the effects of the memory over all the values of the parameter in the...

  • Article
  • Open Access
2 Citations
1,460 Views
18 Pages

29 January 2025

In this paper, we study nonlinear systems of fractional differential equations with a Caputo fractional derivative with respect to another function (CFDF) and we define the strict stability of the zero solution of the considered nonlinear system. As...

  • Article
  • Open Access
1,708 Views
12 Pages

Unified Convergence Criteria of Derivative-Free Iterative Methods for Solving Nonlinear Equations

  • Samundra Regmi,
  • Ioannis K. Argyros,
  • Stepan Shakhno and
  • Halyna Yarmola

A local and semi-local convergence is developed of a class of iterative methods without derivatives for solving nonlinear Banach space valued operator equations under the classical Lipschitz conditions for first-order divided differences. Special cas...

  • Article
  • Open Access
31 Citations
3,494 Views
12 Pages

In this paper, nonlinear nonautonomous equations with the generalized proportional Caputo fractional derivative (GPFD) are considered. Some stability properties are studied by the help of the Lyapunov functions and their GPFDs. A scalar nonlinear fra...

  • Article
  • Open Access
8 Citations
3,108 Views
20 Pages

15 November 2019

The functional Schrödinger representation of a nonlinear scalar quantum field theory in curved space-time is shown to emerge as a singular limit from the formulation based on precanonical quantization. The previously established relationship bet...

  • Feature Paper
  • Article
  • Open Access
5 Citations
3,019 Views
13 Pages

On a Class of Functional Differential Equations with Symmetries

  • Nataliya Dilna,
  • Michal Fečkan and
  • András Rontó

27 November 2019

It is shown that a class of symmetric solutions of scalar non-linear functional differential equations can be investigated by using the theory of boundary value problems. We reduce the question to a two-point boundary value problem on a bounded inter...

  • Feature Paper
  • Article
  • Open Access
2,462 Views
11 Pages

On the Semi-Local Convergence of a Fifth-Order Convergent Method for Solving Equations

  • Christopher I. Argyros,
  • Ioannis K. Argyros,
  • Stepan Shakhno and
  • Halyna Yarmola

20 January 2022

We study the semi-local convergence of a three-step Newton-type method for solving nonlinear equations under the classical Lipschitz conditions for first-order derivatives. To develop a convergence analysis, we use the approach of restricted converge...

  • Feature Paper
  • Article
  • Open Access
2 Citations
2,252 Views
8 Pages

On the Semi-Local Convergence of a Jarratt-Type Family Schemes for Solving Equations

  • Christopher I. Argyros,
  • Ioannis K. Argyros,
  • Stepan Shakhno and
  • Halyna Yarmola

17 February 2022

We study semi-local convergence of two-step Jarratt-type method for solving nonlinear equations under the classical Lipschitz conditions for first-order derivatives. To develop a convergence analysis we use the approach of restricted convergence regi...

  • Article
  • Open Access
9 Citations
2,637 Views
10 Pages

We propose a derivative free one-point method with memory of order 1.84 for solving nonlinear equations. The formula requires only one function evaluation and, therefore, the efficiency index is also 1.84. The methodology is carried out by approximat...

  • Article
  • Open Access
2 Citations
5,625 Views
13 Pages

Exact Solution and Exotic Fluid in Cosmology

  • Seyen Kouwn,
  • Taeyoon Moon and
  • Phillial Oh

20 September 2012

We investigate cosmological consequences of nonlinear sigma model coupled with a cosmological fluid which satisfies the continuity equation. The target space action is of the de Sitter type and is composed of four scalar fields. The potential which i...

  • Article
  • Open Access
6 Citations
2,678 Views
30 Pages

Efficient Three-Step Class of Eighth-Order Multiple Root Solvers and Their Dynamics

  • R. A. Alharbey,
  • Munish Kansal,
  • Ramandeep Behl and
  • J. A. Tenreiro Machado

26 June 2019

This article proposes a wide general class of optimal eighth-order techniques for approximating multiple zeros of scalar nonlinear equations. The new strategy adopts a weight function with an approach involving the function-to-function ratio. An exte...

  • Feature Paper
  • Article
  • Open Access
437 Citations
31,236 Views
23 Pages

23 January 2018

Solving differential equations of fractional (i.e., non-integer) order in an accurate, reliable and efficient way is much more difficult than in the standard integer-order case; moreover, the majority of the computational tools do not provide built-i...

  • Article
  • Open Access
6 Citations
1,829 Views
19 Pages

23 October 2020

This paper presents a method of establishing the D-stability terms of the symmetric solution of scalar symmetric linear and nonlinear functional differential equations. We determine the general conditions of the unique solvability of the initial valu...

  • Article
  • Open Access
2 Citations
898 Views
13 Pages

24 November 2024

We investigate the interaction of fermion fields with oscillating domain walls, inspired by breather-type solutions of the sine-Gordon equation, a nonlinear system of fundamental importance. Our study focuses on the fermionic bound states and particl...

  • Article
  • Open Access
4 Citations
1,614 Views
10 Pages

9 November 2024

We consider some non-linear non-homogeneous partial differential equations (PDEs) and derive their exact Green function solution as a functional Taylor expansion in powers of the source. The kind of PDEs we consider are dispersive ones where the exac...

  • Review
  • Open Access
7 Citations
4,027 Views
26 Pages

19 January 2021

To take advantage of the singular properties of matter, as well as to characterize it, we need to interact with it. The role of optical spectroscopies is to enable us to demonstrate the existence of physical objects by observing their response to lig...

  • Feature Paper
  • Article
  • Open Access
1 Citations
858 Views
18 Pages

5 June 2025

A remarkable feature of manifestly covariant quantum gravity theory (CQG-theory) is represented by its unconstrained Hamiltonian structure expressed in evolution form. This permits the identification of the corresponding dynamical evolution parameter...

  • Article
  • Open Access
2 Citations
1,730 Views
10 Pages

1 December 2011

In this paper, the elastic-piezoelectric continuum has been investigated theoretically and its non-linear constitutive equations have been defined. The theory is formulated in the context of continuum electrodynamics. The solid medium is assumed to b...

  • Article
  • Open Access
16 Citations
3,709 Views
15 Pages

14 July 2021

This article considers the possibility of connecting the problems of the engineering synthesis of frequency control systems for induction motor drives (IMD) with the theory of the identification of IMD based on the equations of a generalized AC elect...

  • Article
  • Open Access
1,036 Views
19 Pages

A Novel Terminal Sliding Mode Control with Robust Prescribed-Time Stability

  • Chaimae El Mortajine,
  • Mostafa Bouzi and
  • Abdellah Benaddy

26 August 2025

The present paper investigates a new tool for analyzing stability/convergence properties and robustness against matched perturbations of a class of nonlinear systems. We start with a scalar system, where it is shown that the state can be regulated or...

  • Article
  • Open Access
96 Views
22 Pages

30 January 2026

We develop a novel Steffensen-type iterative solver to solve nonlinear scalar equations without requiring derivatives. A two-parameter one-step scheme without memory is first introduced and analyzed. Its optimal quadratic convergence is then establis...

  • Article
  • Open Access
802 Views
18 Pages

The aim of this paper is to study a nonlinear system of impulsive fractional differential equations and Caputo fractional derivatives with respect to another function (CFF). The main characteristics of these fractional derivatives are two-fold: first...

  • Article
  • Open Access
770 Views
22 Pages

19 February 2025

This paper proposes a new disorder detection method CCF-AE for a scalar dynamic plant based only on its input–output relation using a cross-correlation function and neural network autoencoder. The CCF-AE method does not use the reference model...

  • Article
  • Open Access
1 Citations
1,349 Views
22 Pages

Cross-Validated Functional Generalized Partially Linear Single-Functional Index Model

  • Mustapha Rachdi,
  • Mohamed Alahiane,
  • Idir Ouassou,
  • Abdelaziz Alahiane and
  • Lahoucine Hobbad

26 August 2024

In this paper, we have introduced a functional approach for approximating nonparametric functions and coefficients in the presence of multivariate and functional predictors. By utilizing the Fisher scoring algorithm and the cross-validation technique...

  • Proceeding Paper
  • Open Access
1 Citations
1,722 Views
6 Pages

De Sitter solutions play an important role in cosmology because the knowledge of unstable de Sitter solutions can be useful in describing inflation, whereas stable de Sitter solutions are often used in models of the late-time acceleration of the Univ...

  • Article
  • Open Access
44 Citations
2,953 Views
13 Pages

De Sitter solutions play an important role in cosmology because the knowledge of unstable de Sitter solutions can be useful to describe inflation, whereas stable de Sitter solutions are often used in models of late-time acceleration of the Universe....

  • Article
  • Open Access
8 Citations
3,254 Views
17 Pages

Anti-Newtonian expansions are introduced for scalar quantum field theories and classical gravity. They expand around a limiting theory that evolves only in time while the spatial points are dynamically decoupled. Higher orders of the expansion re-int...

  • Article
  • Open Access
1 Citations
4,627 Views
50 Pages

12 January 2021

Unlike scalar and gauge field theories in four dimensions, gravity is not perturbatively renormalizable and as a result perturbation theory is badly divergent. Often the method of choice for investigating nonperturbative effects has been the lattice...

  • Article
  • Open Access
3 Citations
2,096 Views
7 Pages

20 May 2022

Recently, it has been discovered that a scalar field coupled to a fluid and allowed to be a thermodynamic variable in consistency with the second law of thermodynamics is only of gravity, and, accordingly, the emergence of extended Newtonian gravity...

  • Article
  • Open Access
3 Citations
3,266 Views
12 Pages

A Higher Order Chebyshev-Halley-Type Family of Iterative Methods for Multiple Roots

  • Ramandeep Behl,
  • Eulalia Martínez,
  • Fabricio Cevallos and
  • Diego Alarcón

9 April 2019

The aim of this paper is to introduce new high order iterative methods for multiple roots of the nonlinear scalar equation; this is a demanding task in the area of computational mathematics and numerical analysis. Specifically, we present a new Cheby...

  • Article
  • Open Access
19 Citations
3,137 Views
19 Pages

20 August 2021

Nonlinear phenomena occur in various fields of science, business, and engineering. Research in the area of computational science is constantly growing, with the development of new numerical schemes or with the modification of existing ones. However,...

  • Article
  • Open Access
2 Citations
2,865 Views
29 Pages

Multiobjective Mixed Integer Nonlinear Model to Plan the Schedule for the Final Disposal of the Spent Nuclear Fuel in Finland

  • Outi Montonen,
  • Ville-Pekka Eronen,
  • Timo Ranta,
  • Jani A. S. Huttunen and
  • Marko M. Mäkelä

3 April 2020

The safe disposal of the spent nuclear fuel is the important part of the nuclear power production. In this paper, we model the geological disposal in Finland covering objectives related to the interim storage, the encapsulation facility, the disposal...

  • Article
  • Open Access
14 Citations
3,100 Views
31 Pages

We study new classes of generic off-diagonal and diagonal cosmological solutions for effective Einstein equations in modified gravity theories (MGTs), with modified dispersion relations (MDRs), and encoding possible violations of (local) Lorentz inva...

  • Article
  • Open Access
5 Citations
3,559 Views
21 Pages

30 July 2020

The initial value problem for a special type of scalar nonlinear fractional differential equation with a Riemann–Liouville fractional derivative is studied. The main characteristic of the equation is the presence of the supremum of the unknown...

  • Article
  • Open Access
55 Citations
6,880 Views
15 Pages

An Easily Understandable Grey Wolf Optimizer and Its Application to Fuzzy Controller Tuning

  • Radu-Emil Precup,
  • Radu-Codrut David,
  • Alexandra-Iulia Szedlak-Stinean,
  • Emil M. Petriu and
  • Florin Dragan

10 June 2017

This paper proposes an easily understandable Grey Wolf Optimizer (GWO) applied to the optimal tuning of the parameters of Takagi-Sugeno proportional-integral fuzzy controllers (T-S PI-FCs). GWO is employed for solving optimization problems focused on...

  • Article
  • Open Access
18 Citations
3,705 Views
16 Pages

Three new iterative methods for solving scalar nonlinear equations using weight function technique are presented. The first one is a two-step fifth order method with four function evaluations which is improved from a two-step Newton’s method ha...

  • Article
  • Open Access
1,057 Views
21 Pages

16 October 2025

In real-world applications, finite time convergence to a desired Lyapunov stable equilibrium is often necessary. This notion of stability is known as finite time stability and refers to systems in which the state trajectory reaches an equilibrium in...

  • Article
  • Open Access
15 Citations
7,409 Views
15 Pages

Online Estimation and Correction of Systematic Encoder Line Errors

  • Carla Albrecht,
  • Jan Klöck,
  • Onno Martens and
  • Walter Schumacher

This paper addresses the identification and correction of amplitude and offset errors in the sinusoidal outputs from incremental position encoders. Precise angular position measurement is of high importance in many position control applications. Manu...

  • Article
  • Open Access
8 Citations
1,519 Views
18 Pages

A Novel Lyapunov Asymptotic Eventual Stability Approach for Nonlinear Impulsive Caputo Fractional Differential Equations

  • Jackson E. Ante,
  • Michael P. Ineh,
  • Jonas O. Achuobi,
  • Uwem P. Akai,
  • Jeremiah U. Atsu and
  • Nnanake-Abasi O. Offiong

21 December 2024

This paper investigates the asymptotic eventual stability (AE-S) for nonlinear impulsive Caputo fractional differential equations (ICFDEs) with fixed impulse moments, employing auxiliary Lyapunov functions (ALF) which are specifically constructed as...

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