Skip to Content

775 Results Found

  • Article
  • Open Access
6 Citations
2,441 Views
9 Pages

1 January 2020

In this paper, our purpose is to investigate the vector equilibrium problem of whether the approximate solution representing bounded rationality can converge to the exact solution representing complete rationality. An approximation theorem is proved...

  • Article
  • Open Access
43 Citations
4,082 Views
11 Pages

Statistical Deferred Nörlund Summability and Korovkin-Type Approximation Theorem

  • Hari Mohan Srivastava,
  • Bidu Bhusan Jena and
  • Susanta Kumar Paikray

21 April 2020

The concept of the deferred Nörlund equi-statistical convergence was introduced and studied by Srivastava et al. [Rev. Real Acad. Cienc. Exactas Fís. Nat. Ser. A Mat. (RACSAM) 112 (2018), 1487–1501]. In the present paper, we have st...

(This article belongs to the Special Issue New Frontiers in Applied Mathematics and Statistics)
  • Review
  • Open Access
2 Citations
2,097 Views
18 Pages

15 September 2024

We start by an application the of Krein–Milman theorem to the integral representation of completely monotonic functions. Elements of convex optimization are also mentioned. The paper continues with applications of Hahn–Banach-type theorem...

(This article belongs to the Section E6: Functional Interpolation)
  • Review
  • Open Access
1 Citations
2,424 Views
24 Pages

18 October 2021

We review earlier and recent results on the Markov moment problem and related polynomial approximation on unbounded subsets. Such results allow proving the existence and uniqueness of the solutions for some Markov moment problems. This is the first a...

(This article belongs to the Special Issue Symmetry and Approximation Methods)
  • Article
  • Open Access
73 Citations
5,754 Views
10 Pages

9 February 2022

In this paper, we define and study q-statistical limit point, q-statistical cluster point, q-statistically Cauchy, q-strongly Cesàro and statistically C1q-summable sequences. We establish relationships of q-statistical convergence with q-statisticall...

(This article belongs to the Special Issue Advanced Approximation Techniques and Their Applications)
  • Article
  • Open Access
43 Citations
3,301 Views
20 Pages

Statistically and Relatively Modular Deferred-Weighted Summability and Korovkin-Type Approximation Theorems

  • Hari Mohan Srivastava,
  • Bidu Bhusan Jena,
  • Susanta Kumar Paikray and
  • Umakanta Misra

31 March 2019

The concept of statistically deferred-weighted summability was recently studied by Srivastava et al. (Math. Methods Appl. Sci. 41 (2018), 671–683). The present work is concerned with the deferred-weighted summability mean in various aspects def...

(This article belongs to the Special Issue Integral Transformations, Operational Calculus and Their Applications)
  • Article
  • Open Access
24 Citations
3,015 Views
16 Pages

16 September 2021

In this work we introduce and investigate the ideas of statistical Riemann integrability, statistical Riemann summability, statistical Lebesgue integrability and statistical Lebesgue summability via deferred weighted mean. We first establish some fun...

(This article belongs to the Special Issue Mathematical Tools and Techniques Applicable to Probability Theory and Statistics)
  • Article
  • Open Access
15 Citations
2,657 Views
13 Pages

In this paper, we establish two approximation theorems for the multidimensional fractional Fourier transform via appropriate convolutions. As applications, we study the boundary and initial problems of the Laplace and heat equations with chirp functi...

(This article belongs to the Special Issue Recent Advances in Fractional Fourier Transforms and Applications)
  • Article
  • Open Access
11 Citations
3,254 Views
11 Pages

12 March 2022

Here, in this article, we introduce and systematically investigate the ideas of deferred weighted statistical Riemann integrability and statistical deferred weighted Riemann summability for sequences of functions. We begin by proving an inclusion the...

(This article belongs to the Special Issue Approximation Theory and Related Applications)
  • Article
  • Open Access
1 Citations
742 Views
29 Pages

8 April 2026

This paper investigates fundamental concepts of statistical convergence for double sequences of time-scale functions via the deferred Cesàro summability mean. Several limit properties and inclusion relations between the newly-introduced conver...

(This article belongs to the Section Mathematical Analysis)
  • Review
  • Open Access
3 Citations
2,316 Views
17 Pages

4 August 2022

The present review paper provides recent results on convexity and its applications to the constrained extension of linear operators, motivated by the existence of subgradients of continuous convex operators, the Markov moment problem and related Mark...

(This article belongs to the Special Issue Ordered Topological Vector Spaces, Operators Acting on Them and Related Applications)
  • Article
  • Open Access
6 Citations
1,984 Views
17 Pages

Approximation Properties of the Blending-Type Bernstein–Durrmeyer Operators

  • Yu-Jie Liu,
  • Wen-Tao Cheng,
  • Wen-Hui Zhang and
  • Pei-Xin Ye

21 December 2022

We construct the blending-type modified Bernstein–Durrmeyer operators and investigate their approximation properties. First, we derive the Voronovskaya-type asymptotic theorem for this type of operator. Then, the local and global approximation...

(This article belongs to the Special Issue Numerical Computation, Approximation of Functions and Applied Mathematics)
  • Article
  • Open Access
27 Citations
2,746 Views
24 Pages

31 May 2021

In this paper, we introduce and investigate a new class of the parametric generalization of the Baskakov-Schurer-Szász-Stancu operators, which considerably extends the well-known class of the classical Baskakov-Schurer-Szász-Stancu approximation oper...

(This article belongs to the Special Issue New Directions in Theory of Approximation and Related Problems)
  • Article
  • Open Access
4 Citations
2,541 Views
14 Pages

15 November 2021

In this paper, within the framework of the consistent approach recently introduced for approximate Lie symmetries of differential equations, we consider approximate Noether symmetries of variational problems involving small terms. Then, we state an a...

(This article belongs to the Special Issue Symmetry Methods and Applications for Nonlinear Partial Differential Equations)
  • Article
  • Open Access
10 Citations
2,669 Views
14 Pages

On Hybrid Type Nonlinear Fractional Integrodifferential Equations

  • Faten H. Damag,
  • Adem Kılıçman and
  • Awsan T. Al-Arioi

16 June 2020

In this paper, we introduce and investigate a hybrid type of nonlinear Riemann Liouville fractional integro-differential equations. We develop and extend previous work on such non-fractional equations, using operator theoretical techniques, and find...

(This article belongs to the Special Issue Nonlinear Equations: Theory, Methods, and Applications)
  • Article
  • Open Access
25 Citations
2,135 Views
15 Pages

27 March 2025

This research focuses on the approximation properties of Kantorovich-type operators using Frobenius–Euler–Simsek polynomials. The test functions and central moments are calculated as part of this study. Additionally, uniform convergence a...

(This article belongs to the Special Issue Numerical Methods and Approximation Theory)
  • Article
  • Open Access
7 Citations
1,692 Views
14 Pages

On the Properties of the Modified λ-Bernstein-Stancu Operators

  • Zhi-Peng Lin,
  • Gülten Torun,
  • Esma Kangal,
  • Ülkü Dinlemez Kantar and
  • Qing-Bo Cai

27 September 2024

In this study, a new kind of modified λ-Bernstein-Stancu operators is constructed. Compared with the original λ-Bézier basis function, the newly operator basis function is more concise in form and has certain symmetry beauty. The...

(This article belongs to the Section B: Mathematics)
  • Article
  • Open Access
3 Citations
1,633 Views
15 Pages

Sinusoidal Approximation Theorem for Kolmogorov–Arnold Networks

  • Sergei Gleyzer,
  • Hanh Nguyen,
  • Dinesh P. Ramakrishnan and
  • Eric A. F. Reinhardt

2 October 2025

The Kolmogorov–Arnold representation theorem states that any continuous multivariable function can be exactly represented as a finite superposition of continuous single-variable functions. Subsequent simplifications of this representation invol...

(This article belongs to the Section E: Applied Mathematics)
  • Article
  • Open Access
2 Citations
1,980 Views
15 Pages

27 October 2023

In the realm of generalized modular metric spaces, we substantiate the validity of fixed-point theorems with Branciari contractions. This paper expands and broadens the original theorems in this context. Subsequently, by building upon this foundation...

(This article belongs to the Special Issue Fixed Point Theory and Its Applications in Nonlinear Analysis and Optimization)
  • Feature Paper
  • Article
  • Open Access
111 Citations
4,757 Views
22 Pages

2 March 2019

We construct Stancu-type Bernstein operators based on Bézier bases with shape parameter λ ∈ [ − 1 , 1 ] and calculate their moments. The uniform convergence of the operator and global approximation result by means of...

(This article belongs to the Special Issue Integral Transformations, Operational Calculus and Their Applications)
  • Article
  • Open Access
2 Citations
2,493 Views
21 Pages

Polynomial Approximation over Arbitrary Shape Domains

  • Mohammad J. Mahtabi,
  • Arash Ghasemi,
  • Amirehsan Ghasemi and
  • James C. Newman

25 November 2024

In spectral/finite element methods, a robust and stable high-order polynomial approximation method for the solution can significantly reduce the required number of degrees of freedom (DOFs) to achieve a certain level of accuracy. In this work, a clos...

(This article belongs to the Special Issue Mathematical and Computational Approaches in Applied Mechanics: A Themed Issue Dedicated to Professor J.N. Reddy)
  • Article
  • Open Access
32 Citations
4,294 Views
13 Pages

10 October 2019

Approximation and some other basic properties of various linear and nonlinear operators are potentially useful in many different areas of researches in the mathematical, physical, and engineering sciences. Motivated essentially by this aspect of appr...

(This article belongs to the Special Issue Mathematical Analysis and Applications II)
  • Article
  • Open Access
3,944 Views
11 Pages

24 August 2024

Determining the exact number of primes at large magnitudes is computationally intensive, making approximation methods (e.g., the logarithmic integral, prime number theorem, Riemann zeta function, Chebyshev’s estimates, etc.) particularly valuab...

  • Article
  • Open Access
15 Citations
1,647 Views
15 Pages

21 November 2024

This research work introduces a connection of adjoint Bernoulli’s polynomials and a gamma function as a sequence of linear positive operators. Further, the convergence properties of these sequences of operators are investigated in various funct...

(This article belongs to the Section E: Applied Mathematics)
  • Article
  • Open Access
16 Citations
1,472 Views
17 Pages

22 December 2024

This research work focuses on λ-Szász–Mirakjan operators coupling generalized beta function. The kernel functions used in λ-Szász operators often possess even or odd symmetry. This symmetry influences the behavior of the operator in terms of approxim...

(This article belongs to the Special Issue The Advances of Nonlinear Equations: Mathematical Models, Symmetry and Applications)
  • Article
  • Open Access
9 Citations
1,245 Views
19 Pages

12 January 2026

In this work, we first establish a new connection between adjoint Bernoulli’s polynomials and gamma function as a new sequence of linear positive operators denoted by Sr,ς,λ(.;.). Further, convergence results for these sequences o...

(This article belongs to the Special Issue Numerical Analysis and Scientific Computing for Applied Mathematics)
  • Article
  • Open Access
32 Citations
2,712 Views
20 Pages

Statistical Blending-Type Approximation by a Class of Operators That Includes Shape Parameters λ and α

  • Qing-Bo Cai,
  • Khursheed J. Ansari,
  • Merve Temizer Ersoy and
  • Faruk Özger

2 April 2022

This paper is devoted to studying the statistical approximation properties of a sequence of univariate and bivariate blending-type Bernstein operators that includes shape parameters α and λ and a positive integer. An estimate of the corr...

(This article belongs to the Section E: Applied Mathematics)
  • Article
  • Open Access
9 Citations
1,070 Views
17 Pages

20 September 2025

The goal of this manuscript is to introduce a new Stancu generalization of the modified Szász–Kantorovich operator connecting Riemann–Liouville fractional operators via Charlier polynomials. Further, some estimates are calculated as test functions an...

(This article belongs to the Special Issue Advances in Functional Analysis and Approximation Theory)
  • Article
  • Open Access
9 Citations
652 Views
22 Pages

24 November 2025

This paper aims to extend, within the context of quantum calculus, the α-Bernstein–Schurer operators (α∈[0,1]) to Kantorovich form. Using the Ditzian–Totik modulus of continuity and the Lipschitz-kind maximal function for...

  • Article
  • Open Access
8 Citations
2,409 Views
14 Pages

7 July 2021

In this paper, we consider functional set-valued differential equations in their integral representations that possess integrals symmetrically on both sides of the equations. The solutions have values that are the nonempty compact and convex subsets....

(This article belongs to the Special Issue Symmetry in Functional Equations and Analytic Inequalities II)
  • Article
  • Open Access
7 Citations
883 Views
14 Pages

Degenerate Appell Polynomials Connecting Beta Function as a Family of Operators and Their Approximations

  • Mohammad Farid,
  • Harun Çiçek,
  • Mohammad Ayman-Mursaleen and
  • Nadeem Rao

1 December 2025

This paper introduces a novel family of positive linear operators constructed by blending degenerate Appell polynomials with a classical Beta kernel in the Durrmeyer setting. The operators are defined as Hn(g;u)=∑ƿ=0∞hƿ(n+u;ƛ...

(This article belongs to the Special Issue Symmetries and Fractional Differential Equations: Theory and Applications)
  • Article
  • Open Access
1 Citations
2,418 Views
20 Pages

9 November 2022

In this paper, we defined weighted (Eλ,q)(Cλ,1) statistical convergence. We also proved some properties of this type of statistical convergence by applying (Eλ,q)(Cλ,1) summability method. Moreover, we used (Eλ,q)(C...

(This article belongs to the Special Issue Symmetry in Pure Mathematics and Real and Complex Analysis)
  • Article
  • Open Access
439 Views
21 Pages

On Value Distribution of One Epstein Zeta-Function

  • Kalyan Chakraborty and
  • Antanas Laurinčikas

3 August 2026

The paper is devoted to Epstein zeta-function ζ3(s), s=σ+it, of a quadratic form of three variables. We obtain a probabilistic characterization of the function ζ3(s) in terms of weak convergence of probability measures in the space of...

(This article belongs to the Special Issue Special Functions, Representations and Applications)
  • Article
  • Open Access
14 Citations
1,136 Views
15 Pages

25 April 2025

This study focuses on approximating continuous functions using Frobenius–Euler–Simsek polynomial analogues of Szász operators. Test functions and central moments are computed to study convergence uniformly, approximation order by t...

(This article belongs to the Special Issue Symmetries and Fractional Differential Equations: Theory and Applications)
  • Article
  • Open Access
2,023 Views
9 Pages

11 February 2023

In this paper, we study the best approximation of a fixed fuzzy-number-valued continuous function to a subset of fuzzy-number-valued continuous functions. We also introduce a method to measure the distance between a fuzzy-number-valued continuous fun...

(This article belongs to the Topic Fuzzy Number, Fuzzy Difference, Fuzzy Differential: Theory and Applications)
  • Feature Paper
  • Article
  • Open Access
824 Views
23 Pages

27 February 2026

The Taylor approximation theorem is a fundamental tool in numerical analysis, providing a local polynomial representation of smooth functions. In practical computations, a function f is approximated by a finite Taylor polynomial Pn, and controlling t...

(This article belongs to the Special Issue Advanced Numerical Methods for Differential Equations: Recent Developments, Analysis and Applications)
  • Article
  • Open Access
1 Citations
1,044 Views
20 Pages

In this paper, the finite-approximate controllability for a class of fractional composite relaxation equations with different nonlocal conditions is discussed. Firstly, under the condition that the nonlocal term is compact, the existence of mild solu...

  • Article
  • Open Access
10 Citations
3,044 Views
15 Pages

9 May 2023

The primary objective of this study is to investigate the concept of approximate controllability in fractional evolution equations that involve the ψ-Caputo derivative. Specifically, we examine the scenario where the semigroup is compact and anal...

(This article belongs to the Section B: Mathematics)
  • Article
  • Open Access
1,262 Views
13 Pages

3 July 2023

The full discrete approximation of solutions of nonhomogeneous fractional equations is considered in this paper. The methods of iteration, finite differences and projection are applied to obtain desired formulas of explicit- and implicit-difference s...

(This article belongs to the Special Issue Advanced Analytical and Numerical Methods for Fractional Initial and Boundary Value Problems with Symmetry/Asymmetry)
  • Article
  • Open Access
15 Citations
1,897 Views
17 Pages

30 March 2023

In this manuscript, we investigate the issue of approximate controllability for a certain class of abstract neutral integro-differential equations having non-instantaneous impulsions and being subject to state-dependent delay. Our methodology relies...

(This article belongs to the Section C1: Difference and Differential Equations)
  • Article
  • Open Access
27 Citations
3,324 Views
13 Pages

The objective of this paper is to analyze the approximate controllability of a semilinear stochastic integrodifferential system with nonlocal conditions in Hilbert spaces. The nonlocal initial condition is a generalization of the classical initial co...

  • Article
  • Open Access
2 Citations
1,966 Views
8 Pages

6 August 2024

We calculate the metric of a self-gravitating and collapsing infinitely thin spherical shell in the weak-field and slow-motion limits, and we demonstrate that Birkhoff’s theorem is not consistent with the theory of the post-Newtonian approximat...

(This article belongs to the Section C: Physics)
  • Article
  • Open Access
2 Citations
2,565 Views
24 Pages

The existence, uniqueness, and Carathe´odory’s successive approximation of the fractional neutral stochastic differential equation (FNSDE) in Hilbert space are considered in this paper. First, we give the Carathe´odory’s appro...

(This article belongs to the Section General Mathematics, Analysis)
  • Article
  • Open Access
3 Citations
2,802 Views
13 Pages

An Additively Optimal Interpreter for Approximating Kolmogorov Prefix Complexity

  • Zoe Leyva-Acosta,
  • Eduardo Acuña Yeomans and
  • Francisco Hernandez-Quiroz

20 September 2024

We study practical approximations of Kolmogorov prefix complexity (K) using IMP2, a high-level programming language. Our focus is on investigating the optimality of the interpreter for this language as the reference machine for the Coding Theorem Met...

(This article belongs to the Section Complexity)
  • Article
  • Open Access
635 Views
23 Pages

14 January 2026

Let a={am:m∈N} be a multiplicative periodic sequence of complex numbers. In this paper, we consider the approximation of analytic functions defined in the strip {s=σ+it:1/2<σ<1} by shifts ζ(s+iτ;a) of the zeta-function...

(This article belongs to the Special Issue Stochastic Modeling and Optimization Techniques)
  • Article
  • Open Access
490 Views
9 Pages

15 December 2025

The paper deals with the results of a study of a third-order nonlinear differential equation with moving singular points and critical poles. So far, this type of equation cannot be solved in quadratures. The development of the author’s approach...

(This article belongs to the Special Issue Advances in Nonlinear Differential Equations with Applications)
  • Article
  • Open Access
58 Citations
3,874 Views
14 Pages

A Note on Approximate Controllability of Fractional Semilinear Integrodifferential Control Systems via Resolvent Operators

  • Velusamy Vijayakumar,
  • Kottakkaran Sooppy Nisar,
  • Dimplekumar Chalishajar,
  • Anurag Shukla,
  • Muslim Malik,
  • Ateq Alsaadi and
  • Saud Fahad Aldosary

This article primarily focuses on the approximate controllability of fractional semilinear integrodifferential equations using resolvent operators. Two alternative sets of necessary requirements have been studied. In the first set, we use theories fr...

(This article belongs to the Special Issue New Challenges Arising in Engineering Problems with Fractional and Integer Order II)
  • Article
  • Open Access
781 Views
16 Pages

4 September 2025

This article introduces new sufficient conditions ensuring the interior approximate controllability of semilinear thermoelastic plate equations subject to Dirichlet boundary conditions. The analysis is carried out by reformulating the system as an ab...

(This article belongs to the Special Issue Modern Problems of Analysis, Optimization, Approximation and Their Applications)
  • Article
  • Open Access
1 Citations
1,442 Views
14 Pages

Joint Discrete Universality in the Selberg–Steuding Class

  • Roma Kačinskaitė,
  • Antanas Laurinčikas and
  • Brigita Žemaitienė

8 July 2023

In the paper, we consider the approximation of analytic functions by shifts from the wide class S˜ of L-functions. This class was introduced by A. Selberg, supplemented by J. Steuding, and is defined axiomatically. We prove the so-called joint...

(This article belongs to the Special Issue Theory of Functions and Applications)
  • Article
  • Open Access
299 Views
19 Pages

This paper investigates a class of nonlinear fractional differential equations with boundary value problems involving Caputo–Hadamard-type derivatives. By relaxing the monotonicity constraints on the nonlinear terms and considering more general...

of 16