Yavar Khedmati Yengejeh
Current Organizations / Institutes
The organizations/institutes from the scholar's latest article
Yavar Khedmati Yengejeh has a total of 18 co-authors. Here are the top co-authors by number of shared publications:
- Abbas Najati
Department of Mathematics, Faculty of Mathematical Sciences, University of Mohaghegh Ardabili, Ardabil, Iran
5 shared publications - Javad Sedghi Moghaddam
Department of Mathematics, Faculty of Sciences, University of Mohaghegh Ardabili, Ardabil, Iran
3 shared publications - Mohammad Reza Abdollahpour
University of Mohaghegh Ardabili
3 shared publications - Reza Parvaz
University of Mohaghegh Ardabili
3 shared publications Fatemeh Ghobadzadeh
2 shared publications- Ahmad Yousefian Darani
Department of Mathematics, University of Mohaghegh Ardabili, Ardabil, Iran
1 shared publication
Latest Publications
- 12 December 2025
- Published by Elsevier in Digital Signal Processing
- Vol. 170
Multi-layer image encryption framework using a chaotic system with a dynamic starting point
- 12 December 2025
- Published by Elsevier in Digital Signal Processing
- Vol. 170
Multi-layer image encryption framework using a chaotic system with a dynamic starting point
- Open Access
- 10 May 2025
- Published by MDPI AG in Computation
- Vol. 13 (5) , 115
Three-Dimensional and Multiple Image Encryption Algorithm Using a Fractional-Order Chaotic System
The rapid development of communication in the last decade has heightened the necessity to create a secure platform for transferring data, including images, more than in previous years. One of the methods of secure image transmission is the encryption method. In this work, an encryption algorithm for multiple images is introduced. In the first step of the proposed algorithm, a key generation algorithm based on a chaotic system and wavelet transform is introduced, and in the next step, the encryption algorithm is developed by introducing rearrange and shift functions based on a chaotic system. One of the most important tools used in the proposed algorithm is the hybrid chaotic system, which is obtained by fractional derivatives and the Cat map. Different types of tests used to study the behavior of this system demonstrate the efficiency of the proposed hybrid system. In the last step of the proposed method, various statistical and security tests, including histogram analysis, correlation coefficient analysis, data loss and noise attack simulations, have been performed on the proposed algorithm. The results show that the proposed algorithm performs well in secure transmission.
- 10 May 2025
- Published by MDPI AG in Computation
- Vol. 13 (5) , 115
Open AccessThree-Dimensional and Multiple Image Encryption Algorithm Using a Fractional-Order Chaotic System
The rapid development of communication in the last decade has heightened the necessity to create a secure platform for transferring data, including images, more than in previous years. One of the methods of secure image transmission is the encryption method. In this work, an encryption algorithm for multiple images is introduced. In the first step of the proposed algorithm, a key generation algorithm based on a chaotic system and wavelet transform is introduced, and in the next step, the encryption algorithm is developed by introducing rearrange and shift functions based on a chaotic system. One of the most important tools used in the proposed algorithm is the hybrid chaotic system, which is obtained by fractional derivatives and the Cat map. Different types of tests used to study the behavior of this system demonstrate the efficiency of the proposed hybrid system. In the last step of the proposed method, various statistical and security tests, including histogram analysis, correlation coefficient analysis, data loss and noise attack simulations, have been performed on the proposed algorithm. The results show that the proposed algorithm performs well in secure transmission.
- Open Access
- 1 January 2025
- Published by Wiley in Journal of Mathematics
- Vol. 2025 (1)
Stability Results for Some Functional Equations on 2‐Banach Spaces With Restricted Domains
We have a normed abelian group and a 2‐pre‐Hilbert space with linearly independent elements u and v . Our goal is to prove that any odd map satisfying the inequality ‖ f ( x ) + f ( y ), z ‖ ⩽ ‖ f ( x + y ), z ‖, z ∈ { u , v }, for all with ‖ x ‖ ∗ + ‖ y ‖ ∗ ≥ d and some d ≥ 0, is additive. Then, we examined the stability issue correlated with Cauchy and Jensen functional inequalities on restricted domains for maps from normed abelian groups to 2‐Banach spaces. In addition, we determined the asymptotic behaviors of these functional equations.
- 1 January 2025
- Published by Wiley in Journal of Mathematics
- Vol. 2025 (1)
Open AccessStability Results for Some Functional Equations on 2‐Banach Spaces With Restricted Domains
We have a normed abelian group and a 2‐pre‐Hilbert space with linearly independent elements u and v . Our goal is to prove that any odd map satisfying the inequality ‖ f ( x ) + f ( y ), z ‖ ⩽ ‖ f ( x + y ), z ‖, z ∈ { u , v }, for all with ‖ x ‖ ∗ + ‖ y ‖ ∗ ≥ d and some d ≥ 0, is additive. Then, we examined the stability issue correlated with Cauchy and Jensen functional inequalities on restricted domains for maps from normed abelian groups to 2‐Banach spaces. In addition, we determined the asymptotic behaviors of these functional equations.
- 27 March 2024
- Published by Springer Nature in Journal of Optics
- Vol. 54 (3) , 551-568
Image encryption using a 3D modular hybrid chaotic system and CRC key generator
- 27 March 2024
- Published by Springer Nature in Journal of Optics
- Vol. 54 (3) , 551-568
Image encryption using a 3D modular hybrid chaotic system and CRC key generator
- Open Access
- 1 January 2023
- Published by Walter de Gruyter GmbH in Demonstratio Mathematica
- Vol. 56 (1)
Asymptotic behavior of Fréchet functional equation and some characterizations of inner product spaces
This article presents the general solution of the following functional equation: where is an abelian group and is a linear space. We also investigate its Hyers-Ulam stability on some restricted domains. We apply the obtained results to present some asymptotic behaviors of this functional equation in the framework of normed spaces. Finally, we provide some characterizations of inner product spaces associated with the mentioned functional equation.- 1 January 2023
- Published by Walter de Gruyter GmbH in Demonstratio Mathematica
- Vol. 56 (1)
Open AccessAsymptotic behavior of Fréchet functional equation and some characterizations of inner product spaces
This article presents the general solution of the following functional equation: where is an abelian group and is a linear space. We also investigate its Hyers-Ulam stability on some restricted domains. We apply the obtained results to present some asymptotic behaviors of this functional equation in the framework of normed spaces. Finally, we provide some characterizations of inner product spaces associated with the mentioned functional equation. - 19 December 2022
- Published by Springer Nature in Acta Mathematica Hungarica
- Vol. 168 (2) , 572-586
Functional inequalities associated with additive, quadratic and Drygas functional equations
- 19 December 2022
- Published by Springer Nature in Acta Mathematica Hungarica
- Vol. 168 (2) , 572-586
Functional inequalities associated with additive, quadratic and Drygas functional equations
- 29 November 2022
- Published by World Scientific Pub Co Pte Ltd in International Journal of Bifurcation and Chaos
- Vol. 32 (14)
A New 4D Chaos System with an Encryption Algorithm for Color and Grayscale Images
In this paper, a new 4D chaos system is introduced based on the mathematical structure through composing and transferring. The behavior of the proposed chaotic system is studied using different tests, such as Lyapunov exponent, bifurcation diagram and histogram. In order to show the advantage of the new chaos system, the proposed system is used for image encryption. In the proposed algorithm, in addition to the new chaos system, cellular automata is also used to improve the security of the algorithm. The proposed algorithm has a separate structure for encryption key, which increases the security of the proposed algorithm. The security of the proposed environment which is evaluated using different types of security tests shows the efficiency of the proposed algorithm.
- 29 November 2022
- Published by World Scientific Pub Co Pte Ltd in International Journal of Bifurcation and Chaos
- Vol. 32 (14)
A New 4D Chaos System with an Encryption Algorithm for Color and Grayscale Images
In this paper, a new 4D chaos system is introduced based on the mathematical structure through composing and transferring. The behavior of the proposed chaotic system is studied using different tests, such as Lyapunov exponent, bifurcation diagram and histogram. In order to show the advantage of the new chaos system, the proposed system is used for image encryption. In the proposed algorithm, in addition to the new chaos system, cellular automata is also used to improve the security of the algorithm. The proposed algorithm has a separate structure for encryption key, which increases the security of the proposed algorithm. The security of the proposed environment which is evaluated using different types of security tests shows the efficiency of the proposed algorithm.
- 16 January 2022
- Published by Springer Nature in Journal of Pseudo-Differential Operators and Applications
- Vol. 13 (1) , 1-15
Properties of bounded representations for G-frames
- 16 January 2022
- Published by Springer Nature in Journal of Pseudo-Differential Operators and Applications
- Vol. 13 (1) , 1-15
Properties of bounded representations for G-frames
- Open Access
Properties of bounded representations for $G$-frames
Due to the importance of frame representation by a bounded operator in dynamical sampling, researchers studied the frames of the form $\{T^{i-1} f\}_{i\in \mathbb{N}}$, which $f$ belongs to separable Hilbert space $\mathcal{H}$ and $T\in B(\mathcal{H})$, and investigated the properties of $T$. Given that $g$-frames include the wide range of frames such as fusion frames, the main purpose of this paper is to study the characteristics of the operator $T$ for $g$-frames of the form $\{\Lambda T^{i-1} \in B(\mathcal{H},\mathcal{K}):i\in \mathbb{N}\}$.Open AccessProperties of bounded representations for $G$-frames
Due to the importance of frame representation by a bounded operator in dynamical sampling, researchers studied the frames of the form $\{T^{i-1} f\}_{i\in \mathbb{N}}$, which $f$ belongs to separable Hilbert space $\mathcal{H}$ and $T\in B(\mathcal{H})$, and investigated the properties of $T$. Given that $g$-frames include the wide range of frames such as fusion frames, the main purpose of this paper is to study the characteristics of the operator $T$ for $g$-frames of the form $\{\Lambda T^{i-1} \in B(\mathcal{H},\mathcal{K}):i\in \mathbb{N}\}$. - Open Access
Fibonacci representations of sequences in Hilbert spaces
Dynamical sampling deals with frames of the form $\{T^n\varphi\}_{n=0}^\infty$, where $T \in B(\mathcal{H})$ belongs to certain classes of linear operators and $\varphi\in\mathcal{H}$. The purpose of this paper is to investigate a new representation, namely, Fibonacci representation of sequences $\{f_n\}_{n=1}^\infty$ in a Hilbert space $\mathcal{H}$; having the form $f_{n+2}=T(f_n+f_{n+1})$ for all $n\geqslant 1$ and a linear operator $T :\text{span}\{f_n\}_{n=1}^\infty\to\text{span}\{f_n\}_{n=1}^\infty$. We apply this kind of representations for complete sequences and frames. Finally, we present some properties of Fibonacci representation operators.Open AccessFibonacci representations of sequences in Hilbert spaces
Dynamical sampling deals with frames of the form $\{T^n\varphi\}_{n=0}^\infty$, where $T \in B(\mathcal{H})$ belongs to certain classes of linear operators and $\varphi\in\mathcal{H}$. The purpose of this paper is to investigate a new representation, namely, Fibonacci representation of sequences $\{f_n\}_{n=1}^\infty$ in a Hilbert space $\mathcal{H}$; having the form $f_{n+2}=T(f_n+f_{n+1})$ for all $n\geqslant 1$ and a linear operator $T :\text{span}\{f_n\}_{n=1}^\infty\to\text{span}\{f_n\}_{n=1}^\infty$. We apply this kind of representations for complete sequences and frames. Finally, we present some properties of Fibonacci representation operators.