This paper introduces an efficient image cryptography system.The pro-posed image cryptography system is based on employing the two-dimensional(2D)chaotic henon map(CHM)in the Discrete Fourier Transform(DFT).The propos...This paper introduces an efficient image cryptography system.The pro-posed image cryptography system is based on employing the two-dimensional(2D)chaotic henon map(CHM)in the Discrete Fourier Transform(DFT).The proposed DFT-based CHM image cryptography has two procedures which are the encryption and decryption procedures.In the proposed DFT-based CHM image cryptography,the confusion is employed using the CHM while the diffu-sion is realized using the DFT.So,the proposed DFT-based CHM image crypto-graphy achieves both confusion and diffusion characteristics.The encryption procedure starts by applying the DFT on the image then the DFT transformed image is scrambled using the CHM and the inverse DFT is applied to get the final-ly encrypted image.The decryption procedure follows the inverse procedure of encryption.The proposed DFT-based CHM image cryptography system is exam-ined using a set of security tests like statistical tests,entropy tests,differential tests,and sensitivity tests.The obtained results confirm and ensure the superiority of the proposed DFT-based CHM image cryptography system.These outcomes encourage the employment of the proposed DFT-based CHM image cryptography system in real-time image and video applications.展开更多
为使静止无功发生器(Static Var Generator,SVG)具备无功、谐波及不对称电流综合补偿能力,提出了一种基于同步旋转坐标变换及离散傅立叶变换(Discrete Fourier Transform,DFT)的SVG指令电流检测方法。该方法通过在同步旋转坐标系下进行...为使静止无功发生器(Static Var Generator,SVG)具备无功、谐波及不对称电流综合补偿能力,提出了一种基于同步旋转坐标变换及离散傅立叶变换(Discrete Fourier Transform,DFT)的SVG指令电流检测方法。该方法通过在同步旋转坐标系下进行递归离散傅立叶变换,能够实时检测出负载电流中的无功分量、不对称分量以及特征谐波。利用该方法只用一个控制器就能同时对两种特征谐波分量进行补偿,相对于其他方法运算量大大减小,便于工程实现。仿真和实验验证证明了该方法的有效性。展开更多
基金This research was funded by Deanship of Scientific Research,Taif University Researches Supporting Project number(TURSP-2020/216),Taif University,Taif,Saudi Arabia.
文摘This paper introduces an efficient image cryptography system.The pro-posed image cryptography system is based on employing the two-dimensional(2D)chaotic henon map(CHM)in the Discrete Fourier Transform(DFT).The proposed DFT-based CHM image cryptography has two procedures which are the encryption and decryption procedures.In the proposed DFT-based CHM image cryptography,the confusion is employed using the CHM while the diffu-sion is realized using the DFT.So,the proposed DFT-based CHM image crypto-graphy achieves both confusion and diffusion characteristics.The encryption procedure starts by applying the DFT on the image then the DFT transformed image is scrambled using the CHM and the inverse DFT is applied to get the final-ly encrypted image.The decryption procedure follows the inverse procedure of encryption.The proposed DFT-based CHM image cryptography system is exam-ined using a set of security tests like statistical tests,entropy tests,differential tests,and sensitivity tests.The obtained results confirm and ensure the superiority of the proposed DFT-based CHM image cryptography system.These outcomes encourage the employment of the proposed DFT-based CHM image cryptography system in real-time image and video applications.
文摘为使静止无功发生器(Static Var Generator,SVG)具备无功、谐波及不对称电流综合补偿能力,提出了一种基于同步旋转坐标变换及离散傅立叶变换(Discrete Fourier Transform,DFT)的SVG指令电流检测方法。该方法通过在同步旋转坐标系下进行递归离散傅立叶变换,能够实时检测出负载电流中的无功分量、不对称分量以及特征谐波。利用该方法只用一个控制器就能同时对两种特征谐波分量进行补偿,相对于其他方法运算量大大减小,便于工程实现。仿真和实验验证证明了该方法的有效性。