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Demonstratio Mathematica

ISSN: 2391-4661

Editor-in-chief: Calogero Vetro

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Demonstratio Mathematica is a fully peer-reviewed, open access, electronic journal devoted to functional analysis, approximation theory and related topics. The journal presents a forum where all aspects of these problems can be discussed. The journal provides the readers with free, instant, and permanent access to all content worldwide; and the authors with extensive promotion of published articles, long-term preservation, no space constraints and quick online publication.

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Special / Topical Issues:

Recent Developments in Fixed-Point Theory and Applications
GUEST EDITORS: Santosh Kumar (University of Dar es Salaam, Tanzania), Anita Tomar (Sri Dev Suman Uttarakhand University, India), Cristian Chifu (Babes-Bolyai University, Romania), Mohammad Mursaleen (Aligarh Muslim University, India)
DEADLINE FOR SUBMISSIONS: October 10, 2023
On some integral inequalities, integral equations and applications
GUEST EDITORS: Ahmet O. Akdemir (Ağrı İbrahim Çeçen University, Turkey), Maria Alessandra Ragusa (University of Catania, Italy), Nguyen Huy Tuan (Van Lang University, Vietnam)
DEADLINE FOR SUBMISSIONS: October 15, 2023
Nonlinear Evolution Equations and Their Applications
GUEST EDITORS: Praveen Agarwal (Anand International College of Engineering, India), Dumitru Baleanu (Department of Mathematics, Cankaya University, Turkey), Necati Ozdemir (Balikesir University, Turkey), Mohamed S. Osman (Department of Mathematics, Faculty of Science, Cairo University, Egypt)
DEADLINE FOR SUBMISSIONS: August 15, 2023
Mathematics for Artificial intelligence and Artificial intelligence for Mathematics
GUEST EDITORS: Hadi Jahanshahi (University of Manitoba, Canada), Oscar Castillo (Tijuana Institute of Technology, Mexico)
DEADLINE FOR SUBMISSIONS: October 2, 2023
Fixed Point Theory and Applications to Various Differential/Integral Equations
GUEST EDITORS: Inci M. Erhan (Atilim University, Ankara, Turkey), Nguyen Huy Tuan (Van Lang University, Ho Chi Minh City, Viet Nam)
ADVISORY EDITOR: Erdal Karapinar (Cankaya University, Ankara, Turkey)
Computational and Numerical Methods for Special Functions
GUEST EDITORS: Serkan Araci (Hasan Kalyoncu University, Turkey), Martin Bohner (Missouri University of Science and Technology, USA), Guotao Wang (Shanxi Normal University, China)
DEADLINE FOR SUBMISSIONS: March 31, 2023.

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Volume 56 Issue 1

January 2023

Regular Articles

Open Access January 19, 2023

A novel class of bipolar soft separation axioms concerning crisp points

Baravan A. Asaad, Sagvan Y. Musa

Article number: 20220189

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Abstract

The main objective of this study is to define a new class of bipolar soft (BS) separation axioms known as BS T ˜ ˜ i {\widetilde{\widetilde{T}}}_{i} -space ( i = 0 , 1 , 2 , 3 , 4 ) \left(i=0,1,2,3,4) . This type is defined in terms of ordinary points. We prove that BS T ˜ ˜ i {\widetilde{\widetilde{T}}}_{i} -space implies BS T ˜ ˜ i − 1 {\widetilde{\widetilde{T}}}_{i-1} -space for i = 1 , 2 i=1,2 ; however, the opposite is incorrect, as demonstrated by an example. For i = 0 , 1 , 2 , 3 , 4 i=0,1,2,3,4 , we investigate that every BS T ˜ ˜ i {\widetilde{\widetilde{T}}}_{i} -space is soft T ˜ i {\widetilde{T}}_{i} -space; and we set up a condition in which the reverse is true. Moreover, we point out that a BS subspace of a BS T ˜ ˜ i {\widetilde{\widetilde{T}}}_{i} -space is a BS T ˜ ˜ i {\widetilde{\widetilde{T}}}_{i} -space for i = 0 , 1 , 2 , 3 i=0,1,2,3 .

Open Access January 30, 2023

Duality for convolution on subclasses of analytic functions and weighted integral operators

Ebrahim Amini, Mojtaba Fardi, Shrideh Al-Omari, Kamsing Nonlaopon

Article number: 20220168

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Abstract

In this article, we investigate a class of analytic functions defined on the unit open disc U = { z : ∣ z ∣ < 1 } {\mathcal{U}}=\left\{z:| z| \lt 1\right\} , such that for every f ∈ P α ( β , γ ) f\in {{\mathcal{P}}}_{\alpha }\left(\beta ,\gamma ) , α > 0 \alpha \gt 0 , 0 ≤ β ≤ 1 0\le \beta \le 1 , 0 < γ ≤ 1 0\lt \gamma \le 1 , and ∣ z ∣ < 1 | z| \lt 1 , the inequality Re f ′ ( z ) + 1 − γ α γ z f ″ ( z ) − β 1 − β > 0 {\rm{Re}}\left\{\frac{f^{\prime} \left(z)+\frac{1-\gamma }{\alpha \gamma }z{f}^{^{\prime\prime} }\left(z)-\beta }{1-\beta }\right\}\gt 0 holds. We find conditions on the numbers α , β \alpha ,\beta , and γ \gamma such that P α ( β , γ ) ⊆ S P ( λ ) {{\mathcal{P}}}_{\alpha }\left(\beta ,\gamma )\subseteq SP\left(\lambda ) , for λ ∈ ( − π 2 , π 2 ) \lambda \in \left(-\frac{\pi }{2},\frac{\pi }{2}) , where S P ( λ ) SP\left(\lambda ) denotes the set of all λ \lambda -spirallike functions. We also make use of Ruscheweyh’s duality theory to derive conditions on the numbers α , β , γ \alpha ,\beta ,\gamma and the real-valued function φ \varphi so that the integral operator V φ ( f ) {V}_{\varphi }(f) maps the set P α ( β , γ ) {{\mathcal{P}}}_{\alpha }\left(\beta ,\gamma ) into the set S P ( λ ) SP\left(\lambda ) , provided φ \varphi is non-negative normalized function ( ∫ 0 1 φ ( t ) d t = 1 ) \left({\int }_{0}^{1}\varphi \left(t){\rm{d}}t=1) and V φ ( f ) ( z ) = ∫ 0 1 φ ( t ) f ( t z ) t d t . {V}_{\varphi }(f)\left(z)=\underset{0}{\overset{1}{\int }}\varphi \left(t)\frac{f\left(tz)}{t}{\rm{d}}t.

Open Access February 13, 2023

Existence of a solution to an infinite system of weighted fractional integral equations of a function with respect to another function via a measure of noncompactness

Anupam Das, Marija Paunović, Vahid Parvaneh, Mohammad Mursaleen, Zohreh Bagheri

Article number: 20220192

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Abstract

In this article, some new generalizations of Darbo’s fixed-point theorem are given and the solvability of an infinite system of weighted fractional integral equations of a function with respect to another function is studied. Also, with the help of a proper example, we illustrate our findings.

Open Access February 27, 2023

On the existence of nonnegative radial solutions for Dirichlet exterior problems on the Heisenberg group

Mohamed Jleli

Article number: 20220193

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Abstract

We investigate the existence and nonexistence of nonnegative radial solutions to exterior problems of the form Δ H m u ( q ) + λ ψ ( q ) K ( r ( q ) ) f ( r 2 − Q ( q ) , u ( q ) ) = 0 {\Delta }_{{{\mathbb{H}}}^{m}}u\left(q)+\lambda \psi \left(q)K\left(r\left(q))f\left({r}^{2-Q}\left(q),u\left(q))=0 in B 1 c {B}_{1}^{c} , under the Dirichlet boundary conditions u = 0 u=0 on ∂ B 1 \partial {B}_{1} and lim r ( q ) → ∞ u ( q ) = 0 {\mathrm{lim}}_{r\left(q)\to \infty }u\left(q)=0 . Here, λ ≥ 0 \lambda \ge 0 is a parameter, Δ H m {\Delta }_{{{\mathbb{H}}}^{m}} is the Kohn Laplacian on the Heisenberg group H m = R 2 m + 1 {{\mathbb{H}}}^{m}={{\mathbb{R}}}^{2m+1} , m > 1 m\gt 1 , Q = 2 m + 2 Q=2m+2 , B 1 {B}_{1} is the unit ball in H m {{\mathbb{H}}}^{m} , B 1 c {B}_{1}^{c} is the complement of B 1 {B}_{1} , and ψ ( q ) = ∣ z ∣ 2 r 2 ( q ) \psi \left(q)=\frac{| z{| }^{2}}{{r}^{2}\left(q)} . Namely, under certain conditions on K K and f f , we show that there exists a critical parameter λ ∗ ∈ ( 0 , ∞ ] {\lambda }^{\ast }\in \left(0,\infty ] in the following sense. If 0 ≤ λ < λ ∗ 0\le \lambda \lt {\lambda }^{\ast } , the above problem admits a unique nonnegative radial solution u λ {u}_{\lambda } ; if λ ∗ < ∞ {\lambda }^{\ast }\lt \infty and λ ≥ λ ∗ \lambda \ge {\lambda }^{\ast } , the problem admits no nonnegative radial solution. When 0 ≤ λ < λ ∗ 0\le \lambda \lt {\lambda }^{\ast } , a numerical algorithm that converges to u λ {u}_{\lambda } is provided and the continuity of u λ {u}_{\lambda } with respect to λ \lambda , as well as the behavior of u λ {u}_{\lambda } as λ → λ ∗ − \lambda \to {{\lambda }^{\ast }}^{-} , are studied. Moreover, sufficient conditions on the the behavior of f ( t , s ) f\left(t,s) as s → ∞ s\to \infty are obtained, for which λ ∗ = ∞ {\lambda }^{\ast }=\infty or λ ∗ < ∞ {\lambda }^{\ast }\lt \infty . Our approach is based on partial ordering methods and fixed point theory in cones.

Open Access March 13, 2023

Hyers-Ulam stability of isometries on bounded domains-II

Ginkyu Choi, Soon-Mo Jung

Article number: 20220196

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Abstract

The question of whether there is a true isometry approximating the ε \varepsilon -isometry defined in the bounded subset of the n n -dimensional Euclidean space has long been considered an interesting question. In 1982, Fickett published the first article on this topic, and in early 2000, Alestalo et al. and Väisälä improved Fickett’s result significantly. Recently, the second author of this article published a paper improving the previous results. The main purpose of this article is to significantly improve all of the aforementioned results by applying a basic and intuitive method.

Open Access March 13, 2023

Asymptotic study of Leray solution of 3D-Navier-Stokes equations with exponential damping

Mongi Blel, Jamel Benameur

Article number: 20220208

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Abstract

We study the uniqueness, the continuity in L 2 {L}^{2} , and the large time decay for the Leray solutions of the 3D incompressible Navier-Stokes equations with the nonlinear exponential damping term a ( e b ∣ u ∣ 2 − 1 ) u a\left({e}^{b| u{| }^{{\bf{2}}}}-1)u , ( a , b > 0 a,b\gt 0 ).

Open Access March 21, 2023

Semi-Hyers-Ulam-Rassias stability for an integro-differential equation of order 𝓃

Daniela Inoan, Daniela Marian

Article number: 20220198

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Abstract

The Laplace transform method is applied in this article to study the semi-Hyers-Ulam-Rassias stability of a Volterra integro-differential equation of order n, with convolution-type kernel. This kind of stability extends the original Hyers-Ulam stability whose study originated in 1940. A general integral equation is formulated first, and then some particular cases (polynomial function and exponential function) for the function from the kernel are considered.

Open Access March 21, 2023

Jordan triple (α,β)-higher ∗-derivations on semiprime rings

O. H. Ezzat

Article number: 20220213

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Abstract

In this article, we define the following: Let N 0 {{\mathbb{N}}}_{0} be the set of all nonnegative integers and D = ( d i ) i ∈ N 0 D={\left({d}_{i})}_{i\in {{\mathbb{N}}}_{0}} a family of additive mappings of a ∗ \ast -ring R R such that d 0 = i d R {d}_{0}=i{d}_{R} . D D is called a Jordan ( α , β ) \left(\alpha ,\beta ) - higher ∗ \ast - derivation (resp. a Jordan triple ( α , β ) \left(\alpha ,\beta ) - higher ∗ \ast - derivation ) of R R if d n ( a 2 ) = ∑ i + j = n d i ( β j ( a ) ) d j ( α i ( a ∗ i ) ) {d}_{n}\left({a}^{2})={\sum }_{i+j=n}{d}_{i}\left({\beta }^{j}\left(a)){d}_{j}\left({\alpha }^{i}\left({a}^{{\ast }^{i}})) (resp. d n ( a b a ) = ∑ i + j + k = n d i ( β j + k ( a ) ) d j ( β k ( α i ( b ∗ i ) ) ) d k ( α i + j ( a ∗ i + j ) ) {d}_{n}\left(aba)={\sum }_{i+j+k=n}{d}_{i}\left({\beta }^{j+k}\left(a)){d}_{j}\left({\beta }^{k}\left({\alpha }^{i}\left({b}^{{\ast }^{i}}))){d}_{k}\left({\alpha }^{i+j}\left({a}^{{\ast }^{i+j}})) ) for all a , b ∈ R a,b\in R and each n ∈ N 0 n\in {{\mathbb{N}}}_{0} . We show that the two notions of Jordan ( α , β ) \left(\alpha ,\beta ) -higher ∗ \ast -derivation and Jordan triple ( α , β ) \left(\alpha ,\beta ) -higher ∗ \ast -derivation on a 6-torsion free semiprime ∗ \ast -ring are equivalent.

Special Issue on Fixed Point Theory and Applications to Various Differential/Integral Equation - Part II

Open Access January 19, 2023

On Cauchy problem for pseudo-parabolic equation with Caputo-Fabrizio operator

Bui Dai Nghia, Van Tien Nguyen, Le Dinh Long

Article number: 20220180

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Abstract

In this article, we considered the pseudo-parabolic equation with Caputo-Fabrizio fractional derivative. This equation has many applications in different fields, such as science, technology, and so on. In this article, we gave the formula of mild solution, which is represented in the form of Fourier series by some operators . In the linear case, we investigated the continuity of the mild solution with respect to the fractional order. For the nonlinear case, we investigated the existence and uniqueness of a global solution. The main proof technique is based on the Banach fixed point theorem combined with some Sobolev embeddings. For more detailed, we obtained two other interesting results: the continuity of mild solution with respect to the derivative order and the convergence of solution as the coefficient k approaches to zero.

Open Access January 25, 2023

Fixed-point results for convex orbital operators

Ovidiu Popescu

Article number: 20220184

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Abstract

The aim of this article is to introduce a new type of operator similar to those of A. Petruşel and G. Petruşel type ( Fixed point results for decreasing convex orbital operators , J. Fixed Point Theory Appl. 23 (2021), no. 35) and prove some fixed-point theorems which generalize and complement several results in the theory of nonlinear operators.

Open Access January 25, 2023

Asymptotic stability of equilibria for difference equations via fixed points of enriched Prešić operators

Mădălina Păcurar

Article number: 20220185

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Abstract

We introduced a new general class of Prešić-type operators, by enriching the known class of Prešić contractions. We established conditions under which enriched Prešić operators possess a unique fixed point, proving the convergence of two different iterative methods to the fixed point. We also gave a data dependence result that was finally applied in proving the global asymptotic stability of the equilibrium of a certain k -th order difference equation.

Open Access January 30, 2023

Asymptotic behavior of resolvents of equilibrium problems on complete geodesic spaces

Yasunori Kimura, Keisuke Shindo

Article number: 20220187

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Abstract

In this article, we discuss equilibrium problems and their resolvents on complete geodesic spaces. In particular, we consider asymptotic behavior and continuity of resolvents with positive parameter in a complete geodesic space whose curvature is bounded above. Furthermore, we apply these results to resolvents of convex functions.

Open Access February 13, 2023

A system of additive functional equations in complex Banach algebras

Siriluk Paokanta, Mehdi Dehghanian, Choonkil Park, Yamin Sayyari

Article number: 20220165

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Abstract

In this article, we solve the system of additive functional equations: 2 f ( x + y ) − g ( x ) = g ( y ) , g ( x + y ) − 2 f ( y − x ) = 4 f ( x ) \left\{\phantom{\rule[-1.25em]{}{0ex}}\begin{array}{l}2f\left(x+y)-g\left(x)=g(y),\\ g\left(x+y)-2f(y-x)=4f\left(x)\end{array}\right. and prove the Hyers-Ulam stability of the system of additive functional equations in complex Banach spaces. Furthermore, we prove the Hyers-Ulam stability of f f -hom-ders in Banach algebras.

Open Access February 15, 2023

New inertial forward–backward algorithm for convex minimization with applications

Kunrada Kankam, Watcharaporn Cholamjiak, Prasit Cholamjiak

Article number: 20220188

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Abstract

In this work, we present a new proximal gradient algorithm based on Tseng’s extragradient method and an inertial technique to solve the convex minimization problem in real Hilbert spaces. Using the stepsize rules, the selection of the Lipschitz constant of the gradient of functions is avoided. We then prove the weak convergence theorem and present the numerical experiments for image recovery. The comparative results show that the proposed algorithm has better efficiency than other methods.

Open Access February 15, 2023

Uniqueness of solutions for a ψ-Hilfer fractional integral boundary value problem with the p-Laplacian operator

Ahmed Alsaedi, Madeaha Alghanmi, Bashir Ahmad, Boshra Alharbi

Article number: 20220195

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Abstract

In this article, we discuss the existence of a unique solution to a ψ \psi -Hilfer fractional differential equation involving the p p -Laplacian operator subject to nonlocal ψ \psi -Riemann-Liouville fractional integral boundary conditions. Banach’s fixed point theorem is the main tool of our study. Examples are given for illustrating the obtained results.

Open Access February 24, 2023

Analysis of Cauchy problem with fractal-fractional differential operators

Nadiyah Hussain Alharthi, Abdon Atangana, Badr S. Alkahtani

Article number: 20220181

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Abstract

Cauchy problems with fractal-fractional differential operators with a power law, exponential decay, and the generalized Mittag-Leffler kernels are considered in this work. We start with deriving some important inequalities, and then by using the linear growth and Lipchitz conditions, we derive the conditions under which these equations admit unique solutions. A numerical scheme was suggested for each case to derive a numerical solution to the equation. Some examples of fractal-fractional differential equations were presented, and their exact solutions were obtained and compared with the used numerical scheme. A nonlinear case was considered and solved, and numerical solutions were presented graphically for different values of fractional orders and fractal dimensions.

Open Access March 28, 2023

The asymptotic behaviors of solutions for higher-order (m₁, m₂)-coupled Kirchhoff models with nonlinear strong damping

Penghui Lv, Guoguang Lin, Xiaojun Lv

Article number: 20220197

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Abstract

The Kirchhoff model is derived from the vibration problem of stretchable strings. This article focuses on the long-time dynamics of a class of higher-order coupled Kirchhoff systems with nonlinear strong damping. The existence and uniqueness of the solutions of these equations in different spaces are proved by prior estimation and the Faedo-Galerkin method. Subsequently, the family of global attractors of these problems is proved using the compactness theorem. In this article, we systematically propose the definition and proof process of the family of global attractors and enrich the related conclusions of higher-order coupled Kirchhoff models. The conclusions lay a theoretical foundation for future practical applications.

Special Issue on Computational and Numerical Methods for Special Functions

Open Access January 19, 2023

Sandwich-type results regarding Riemann-Liouville fractional integral of q-hypergeometric function

Alina Alb Lupaş, Georgia Irina Oros

Article number: 20220186

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Abstract

The study presented in this article involves q -calculus connected to fractional calculus applied in the univalent functions theory. Riemann-Liouville fractional integral of q -hypergeometric function is defined here, and investigations are conducted using the theories of differential subordination and superordination. Theorems and corollaries containing new subordination and superordination results are proved for which best dominants and best subordinants are given, respectively. As an application of the results obtained by the means of the two theories, the statement of a sandwich-type theorem concludes the study.

Open Access February 15, 2023

Certain aspects of Nörlund ℐ-statistical convergence of sequences in neutrosophic normed spaces

Ömer Kişi, Mehmet Gürdal, Burak Çakal

Article number: 20220194

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Abstract

The aim of this article is to investigate the neutrosophic Nörlund ℐ -statistically convergent sequence space. We present some neutrosophic normed spaces (NNSs) in Nörlund convergent spaces. In addition, we also examine various topological and algebraic properties of these convergent sequence spaces. Theorems are proved in light of the NNS theory approach. Results are obtained via different perspectives and new examples are produced to justify the counterparts and show the existence of the introduced notions. The results established in this research work supply an exhaustive foundation in NNS and make a significant contribution to the theoretical development of NNS in the literature. The original aspect of this study is the first wholly up-to-date and thorough examination of the features and implementation of neutrosophic Nörlund ℐ -statistically convergent sequences in NNS, based upon the standard definition.

Open Access March 23, 2023

On completeness of weak eigenfunctions for multi-interval Sturm-Liouville equations with boundary-interface conditions

Hayati Olgar

Article number: 20220210

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Abstract

The goal of this study is to analyse the eigenvalues and weak eigenfunctions of a new type of multi-interval Sturm-Liouville problem (MISLP) which differs from the standard Sturm-Liouville problems (SLPs) in that the Strum-Liouville equation is defined on a finite number of non-intersecting subintervals and the boundary conditions are set not only at the endpoints but also at finite number internal points of interaction. For the self-adjoint treatment of the considered MISLP, we introduced some self-adjoint linear operators in such a way that the considered multi-interval SLPs can be interpreted as operator-pencil equation. First, we defined a concept of weak solutions (eigenfunctions) for MISLPs with interface conditions at the common ends of the subintervals. Then, we found some important properties of eigenvalues and corresponding weak eigenfunctions. In particular, we proved that the spectrum is discrete and the system of weak eigenfunctions forms a Riesz basis in appropriate Hilbert space.

Special Issue on Recent Methods in Approximation Theory - Part II

Open Access February 8, 2023

On the order of approximation by modified summation-integral-type operators based on two parameters

Syed Abdul Mohiuddine, Karunesh Kumar Singh, Abdullah Alotaibi

Article number: 20220182

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Abstract

In this article, we the study generalized family of positive linear operators based on two parameters, which are a broad family of many well-known linear positive operators, e.g., Baskakov-Durrmeyer, Baskakov-Szász, Szász-Beta, Lupaş-Beta, Lupaş-Szász, genuine Bernstein-Durrmeyer, and Pǎltǎnea. We first find direct estimates in terms of the second-order modulus of continuity, then we find an estimate of error in the Ditzian-Totik modulus of smoothness. Then we discuss the rate of approximation for functions in the Lipschitz class. Furthermore, we study the pointwise Grüss-Voronovskaja-type result and also establish the Grüss-Voronovskaja-type asymptotic formula in quantitative form.

Open Access March 13, 2023

Bernstein-type operators on elliptic domain and their interpolation properties

Mohammad Iliyas, Asif Khan, Mohammad Mursaleen

Article number: 20220199

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Abstract

The aim of this article is to construct univariate Bernstein-type operators ( ℬ m x G ) ( x , z ) \left({{\mathcal{ {\mathcal B} }}}_{m}^{x}G)\left(x,z) and ( ℬ n z G ) ( x , z ) , \left({{\mathcal{ {\mathcal B} }}}_{n}^{z}G)\left(x,z), their products ( P m n G ) ( x , z ) \left({{\mathcal{P}}}_{mn}G)\left(x,z) , ( Q n m G ) ( x , z ) \left({{\mathcal{Q}}}_{nm}G)\left(x,z) , and their Boolean sums ( S m n G ) ( x , z ) \left({{\mathcal{S}}}_{mn}G)\left(x,z) , ( T n m G ) ( x , z ) \left({{\mathcal{T}}}_{nm}G)\left(x,z) on elliptic region, which interpolate the given real valued function G G defined on elliptic region on its boundary. The bound of the remainders of each approximation formula of corresponding operators are computed with the help of Peano’s theorem and modulus of continuity, and the rate of convergence for functions of Lipschitz class is computed.

Special Issue on Recent Advances in Fractional Calculus and Nonlinear Fractional Evaluation Equations - Part II

Open Access March 21, 2023

Application of fractional quantum calculus on coupled hybrid differential systems within the sequential Caputo fractional q-derivatives

Jehad Alzabut, Mohamed Houas, Mohamed I. Abbas

Article number: 20220205

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Abstract

In the current manuscript, we combine the q -fractional integral operator and q -fractional derivative to investigate a coupled hybrid fractional q -differential systems with sequential fractional q -derivatives. The existence and uniqueness of solutions for the proposed system are established by means of Leray-Schauder’s alternative and the Banach contraction principle. Furthermore, the Ulam-Hyers and Ulam-Hyers-Rassias stability results are discussed. Finally, two illustrative examples are given to highlight the theoretical findings.

Volume 49 (2016)

Volume 48 (2015)

Volume 47 (2014)

Volume 46 (2013)

Volume 45 (2012)

Volume 44 (2011)

Volume 43 (2010)

Volume 42 (2009)

Volume 41 (2008)

Volume 40 (2007)

Volume 39 (2006)

Volume 38 (2005)

Volume 37 (2004)

Volume 36 (2003)

Volume 35 (2002)

Volume 34 (2001)

Volume 33 (2000)

Volume 32 (1999)

Volume 31 (1998)

Volume 30 (1997)

Volume 29 (1996)

Volume 28 (1995)

Volume 27 (1994)

Volume 26 (1993)

Volume 25 (1992)

Volume 24 (1991)

Volume 23 (1990)

Volume 22 (1989)

Volume 21 (1988)

Volume 20 (1987)

Volume 19 (1986)

Volume 18 (1985)

Volume 17 (1984)

Volume 16 (1983)

Volume 15 (1982)

Volume 14 (1981)

Volume 13 (1980)

Issue 4

Volume 12 (1979)

Volume 11 (1978)

Volume 10 (1977)

Volume 9 (1976)

Volume 8 (1975)

Volume 7 (1974)

Volume 5 (1973)

Volume 4 (1972)

Volume 3 (1971)

Volume 2 (1970)

Volume 1 (1969)

5-year Impact Factor	1.399
Cite Score	2.8
Index Copernicus Value	130.21
Impact Factor	2.093
Journal Citation Indicator	1.65
Mathematical Citation Quotient	0.43
SCImago Journal Rank	0.617
Source Normalized Impact per Paper	1.471

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For detailed information, please see Instruction for Authors.

EDITORIAL POLICY
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Conflict of interest: When authors submit a manuscript, they are responsible for recognizing and disclosing financial and/or other conflicts of interest that might bias their work and/or could inappropriately influence his/her judgment. If no specified acknowledgement is given, the Editors assume that no conflict of interest exists. Authors are encouraged to fill in the ICMJE Conflicts of Interest Form (available here) and send it in the electronic format to the Managing Editor.
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Authorship: Authorship should be limited to those who have made a significant contribution to the conception, design, execution, or interpretation of the reported study. All those who have made significant contributions should be listed as co-authors. Where there are others who have participated in certain substantive aspects of the research project, they should be named in an Acknowledgement section. The corresponding author should ensure that all appropriate co-authors (according to the above definition) and no inappropriate co-authors are included in the author list of the manuscript, and that all co-authors have seen and approved the final version of the paper and have agreed to its submission for publication.
Peer Review process: Our standard policy requires each paper to be reviewed by at least two Referees and the peer-review process is single-blind. The Editors reserve the right to decline the submitted manuscript without review, if the studies reported are not sufficiently novel or important to merit publication in the journal. Manuscripts deemed unsuitable (insufficient originality or of limited interest to the target audience) are returned to the author(s) without review. The Editor seeks advice from experts in the appropriate field. Research articles and communications are refereed by a minimum of two reviewers, review papers by at least three. Authors are requested to suggest persons competent to review their manuscript. However, please note that this will be treated only as a suggestion, and the final selection of reviewers is exclusively the Editor's decision. The final decision of acceptance is made by Managing Editor or, in case of conflict, by the Editor-in-Chief.
Scientific Misconduct: This journal publishes only original manuscripts that are not also published or going to be published elsewhere. Multiple submissions/publications, or redundant publications (re-packaging in different words of data already published by the same authors) will be rejected. If they are detected only after publication, the journal reserves the right to publish a Retraction Note. In each particular case Editors will follow COPE’s Core Practices and implement the advices.

Editorial

Editor-in-Chief
Calogero Vetro, University of Palermo, Italy

Editorial Advisory Board
George Anastassiou, University of Memphis, USA
Marlene Frigon, University of Montréal, Canada
Doron Lubinsky, Georgia Institute of Technology, USA
Gradimir V. Milovanovic, Serbian Academy of Sciences and Arts, Serbia
Dumitru Motreanu, University of Perpignan, France
Donal O'Regan, National University of Ireland, Galway, Ireland
Tohru Ozawa, Waseda University, Japan
Tao Qian, University of Macau, China
Vicentiu Radulescu, AGH University of Science and Technology, Poland
Themistocles M. Rassias, National Technical University of Athens, Greece
Simeon Reich, Technion - Israel Institute of Technology, Israel
Bessem Samet, King Saud University, Saudi Arabia
Hari Mohan Srivastava, University of Victoria, Canada

Editorial Board
Tuncer Acar, Selcuk University, Turkey
Pietro Aiena, University of Palermo, Italy
Francesco Altomare, University of Bari, Italy
Esteban Andruchow, National University of General Sarmiento, Argentina
Ali Aral, Kirikkale University, Turkey
Dariusz Bugajewski, Adam Mickiewicz University, Poznań, Poland
Oktay Duman, TOBB University of Economics and Technology, Turkey
Hemen Dutta, University of Gauhati, India
Giovany Figueiredo, Universidade de Brasília, Brasil
Xian-Ming Gu, Southwestern University of Finance and Economics, China
Antonio Iannizzotto, University of Cagliari, Italy
Zenon Jabłoński, Jagiellonian University, Poland
Chao Ji, East China University of Science and Technology, China
Anna Kaminska, University of Memphis, USA
Wiesław Krawcewicz, University of Texas at Dallas, USA
Alberto Lastra, University of Alcalá, Spain
Alexander Lomtatidze, Brno University of Technology, Czech Republic
Giuseppe Marino, University of Calabria, Italy
Salah Mahmoud Boulaaras, Department of Mathematics, College of Sciences and Arts in ArRass, Qassim University, Saudi Arabia
Vladimir Müller, Academy of Sciences of the Czech Republic, Czech Republic
Dorian Popa, Technical University of Cluj-Napoca, Romania
Ioan Rasa, Technical University of Cluj-Napoca, Romania
Dušan D. Repovš, University of Ljubljana, Slovenia
Enrique A. Sánchez-Pérez, Technical University of Valencia, Spain
Wasfi Shatanawi, Hashemite University, Zarqa, Jordan
Plamen Simeonov, University of Houston-Downtown, USA
Tomonari Suzuki, Kyushu Institute of Technology, Japan
Sergey Tikhonov, ICREA, Centre De Recerca Matemàtica and UAB, Barcelona, Spain
Gianluca Vinti, University of Perugia, Italy
Dariusz Wardowski, University of Lodz, Poland
Eric Weber, Iowa State University, USA
Patrick Winkert, Technische Universität Berlin, Germany
Minbo Yang, Zhejiang Normal University, China.
Xiao-Jun Yang, China University of Mining and Technology, China
Shengda Zeng, Yulin Normal University, China
Bentuo Zheng, University of Memphis, USA
Jiabin Zuo, Guangzhou University, China

Assistant Editors
Piotr Kasprzak, Adam Mickiewicz University, Poland

Language Editors
John Evans, University of Coventry, UK
Katerina Hristova, University of East Anglia, UK

Publisher
DE GRUYTER Poland
Bogumila Zuga 32A Str.
01-811 Warsaw, Poland
T: +48 22 701 50 15

Editorial Contact
Deepan Selvaraj
Assistant Managing Editor, Compuscript
AssistantManagingEditor@degruyter.com

Managing Editor
Monika Maleszka
Monika Maleszka@degruyter.com

(Deutsch)

Type: Journal
Language: English
Publisher: De Gruyter Open Access
First published: March 7, 2014
Publication Frequency: 1 Issue per Year
Audience: Scientists, graduate students, and experts in mathematics.

Demonstratio Mathematica

A novel class of bipolar soft separation axioms concerning crisp points

Abstract

Duality for convolution on subclasses of analytic functions and weighted integral operators

Abstract

Existence of a solution to an infinite system of weighted fractional integral equations of a function with respect to another function via a measure of noncompactness

Abstract

On the existence of nonnegative radial solutions for Dirichlet exterior problems on the Heisenberg group

Abstract

Hyers-Ulam stability of isometries on bounded domains-II

Abstract

Asymptotic study of Leray solution of 3D-Navier-Stokes equations with exponential damping

Abstract

Semi-Hyers-Ulam-Rassias stability for an integro-differential equation of order 𝓃

Abstract

Jordan triple (α,β)-higher ∗-derivations on semiprime rings

Abstract

On Cauchy problem for pseudo-parabolic equation with Caputo-Fabrizio operator

Abstract

Fixed-point results for convex orbital operators

Abstract

Asymptotic stability of equilibria for difference equations via fixed points of enriched Prešić operators

Abstract

Asymptotic behavior of resolvents of equilibrium problems on complete geodesic spaces

Abstract

A system of additive functional equations in complex Banach algebras

Abstract

New inertial forward–backward algorithm for convex minimization with applications

Abstract

Uniqueness of solutions for a ψ-Hilfer fractional integral boundary value problem with the p-Laplacian operator

Abstract

Analysis of Cauchy problem with fractal-fractional differential operators

Abstract

The asymptotic behaviors of solutions for higher-order (m1, m2)-coupled Kirchhoff models with nonlinear strong damping

Abstract

Sandwich-type results regarding Riemann-Liouville fractional integral of q-hypergeometric function

Abstract

Certain aspects of Nörlund ℐ-statistical convergence of sequences in neutrosophic normed spaces

Abstract

On completeness of weak eigenfunctions for multi-interval Sturm-Liouville equations with boundary-interface conditions

Abstract

On the order of approximation by modified summation-integral-type operators based on two parameters

Abstract

Bernstein-type operators on elliptic domain and their interpolation properties

Abstract

Application of fractional quantum calculus on coupled hybrid differential systems within the sequential Caputo fractional q-derivatives

Abstract

The asymptotic behaviors of solutions for higher-order (m₁, m₂)-coupled Kirchhoff models with nonlinear strong damping