Int. J. Bifurc. Chaos最新文献_第6页

Bifurcation Analysis of a Wind Turbine Generator Drive System with Stochastic Excitation Under Both Displacement and Velocity Delayed Feedback 具有随机激励的风力发电机组驱动系统在位移和速度延迟反馈下的分岔分析

Int. J. Bifurc. Chaos Pub Date : 2023-06-15 DOI: 10.1142/S0218127423500797

J. Zhang, Mengran Nan, Lixiang Wei, Xinlei An, Meijuan He

{"title":"Bifurcation Analysis of a Wind Turbine Generator Drive System with Stochastic Excitation Under Both Displacement and Velocity Delayed Feedback","authors":"J. Zhang, Mengran Nan, Lixiang Wei, Xinlei An, Meijuan He","doi":"10.1142/S0218127423500797","DOIUrl":"https://doi.org/10.1142/S0218127423500797","url":null,"abstract":"In this paper, a wind turbine generator drive system with stochastic excitation under both displacement and velocity delayed feedback is considered. Firstly, the center manifold method is used to approximate the delay term of the system, so that the Itô-stochastic differential equation can be obtained by random average method. Through the maximal Lyapunov exponential method, the local stochastic stability and random D-bifurcation conditions of the system are obtained. Secondly, it is verified that the increase of noise intensity and delay value induces the occurrence of random P-bifurcation of the system through Monte Carlo numerical simulations. In addition, the theoretical chaos threshold of the system is derived by the random Melnikov method. The results show that the chaos threshold decreases as the noise intensity increases, and the increase in time delay leads to a delay in the chaotic behavior of the system. Finally, the correctness and effectiveness of the chaos-theoretic analysis are verified based on the one-parameter bifurcation diagrams and the two-parameter bifurcation diagrams.","PeriodicalId":13688,"journal":{"name":"Int. J. Bifurc. Chaos","volume":null,"pages":null},"PeriodicalIF":0.0,"publicationDate":"2023-06-15","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"91467179","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":0,"RegionCategory":"","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}

引用次数: 0

Minimal Chaotic Networks of Linear Neuron-Like Elements with Single Rectification: Three Prototypes 单整流线性类神经元单元的最小混沌网络:三个原型

Int. J. Bifurc. Chaos Pub Date : 2023-06-15 DOI: 10.1142/S0218127423300173

Y. Horikawa

引用次数: 0

Estimating the Number of Zeros of Abelian Integrals for the Perturbed Cubic Z4-Equivariant Planar Hamiltonian System 摄动三次z4等变平面哈密顿系统的阿贝尔积分零点数的估计

Int. J. Bifurc. Chaos Pub Date : 2023-06-15 DOI: 10.1142/S0218127423500852

Aiyong Chen, Wentao Huang, Yonghui Xia, Huiyang Zhang

{"title":"Estimating the Number of Zeros of Abelian Integrals for the Perturbed Cubic Z4-Equivariant Planar Hamiltonian System","authors":"Aiyong Chen, Wentao Huang, Yonghui Xia, Huiyang Zhang","doi":"10.1142/S0218127423500852","DOIUrl":"https://doi.org/10.1142/S0218127423500852","url":null,"abstract":"We analyze the dynamics of a class of [Formula: see text]-equivariant Hamiltonian systems of the form [Formula: see text], where [Formula: see text] is complex, the time [Formula: see text] is real, while [Formula: see text] and [Formula: see text] are real parameters. The topological phase portraits with at least one center are given. The finite generators of Abelian integral [Formula: see text] are obtained, where [Formula: see text] is a family of closed ovals defined by [Formula: see text] [Formula: see text], [Formula: see text] is the open interval on which [Formula: see text] is defined, [Formula: see text], [Formula: see text] are real polynomials in [Formula: see text] and [Formula: see text] with degree [Formula: see text]. We give an estimation of the number of isolated zeros of the corresponding Abelian integral by using its algebraic structure. We show that for the given polynomials [Formula: see text] and [Formula: see text] in [Formula: see text] and [Formula: see text] with degree [Formula: see text], the number of the limit cycles of the perturbed [Formula: see text]-equivariant Hamiltonian system does not exceed [Formula: see text] (taking into account the multiplicity).","PeriodicalId":13688,"journal":{"name":"Int. J. Bifurc. Chaos","volume":null,"pages":null},"PeriodicalIF":0.0,"publicationDate":"2023-06-15","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"90072136","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":0,"RegionCategory":"","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}

引用次数: 0

Multibiometric Images Encryption Method Based on Fast Fourier Transform and Hyperchaos 基于快速傅里叶变换和超混沌的多生物特征图像加密方法

Int. J. Bifurc. Chaos Pub Date : 2023-06-15 DOI: 10.1142/S0218127423500840

Cong Ding, Ru Xue, Shi-Jin Niu

{"title":"Multibiometric Images Encryption Method Based on Fast Fourier Transform and Hyperchaos","authors":"Cong Ding, Ru Xue, Shi-Jin Niu","doi":"10.1142/S0218127423500840","DOIUrl":"https://doi.org/10.1142/S0218127423500840","url":null,"abstract":"Biometric images are an important means of personal identity verification and identification and are related to personal privacy and property security. To address the problems of poor security and low image reconstruction quality in the encryption and transmission of multibiometric images, a multibiometric images encryption method based on Fast Fourier Transform (FFT) and hyperchaotic system is proposed. First, the FFT is used to transform the multibiometric images from spatial to frequency domain. Then, the initial values of the hyperchaotic Lorenz system are generated using a one-dimensional chaotic logistic system to generate the key stream. Combined with the recoding rules of matrix reconstruction and scrambling without repetition of using multimatrix, the multiple matrices of amplitude and phase in the transform domain are reconstructed to be multiple RGB three-channel color images by using the inverse fast Fourier transform. Then, we combine the two diffusion methods of additive mode and Galois domain diffusion on each color channel to perform confusion and diffusion. Finally, the multiple grayscale images are encrypted to become multiple color images. The experimental results demonstrate that the method can effectively defend against various attacks. In addition, it solves the problem of low reconstruction accuracy that exists in the field of multiple images security.","PeriodicalId":13688,"journal":{"name":"Int. J. Bifurc. Chaos","volume":null,"pages":null},"PeriodicalIF":0.0,"publicationDate":"2023-06-15","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"90761983","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":0,"RegionCategory":"","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}

引用次数: 0

Impact of Spatial Memory on a Predator-Prey System with Allee Effect 空间记忆对具有狭缝效应的捕食系统的影响

Int. J. Bifurc. Chaos Pub Date : 2023-06-15 DOI: 10.1142/s0218127423500864

Daiyong Wu, Fengping Lu, Chuansheng Shen, Jian Gao

引用次数: 0

Propagation Effect of Epileptic Seizures in a Coupled Thalamocortical Network 耦合丘脑皮质网络中癫痫发作的传播效应

Int. J. Bifurc. Chaos Pub Date : 2023-06-15 DOI: 10.1142/S0218127423500785

Luyao Yan, Honghui Zhang, Zhongkui Sun, Zilu Cao, Zhuan Shen, Lin Du

{"title":"Propagation Effect of Epileptic Seizures in a Coupled Thalamocortical Network","authors":"Luyao Yan, Honghui Zhang, Zhongkui Sun, Zilu Cao, Zhuan Shen, Lin Du","doi":"10.1142/S0218127423500785","DOIUrl":"https://doi.org/10.1142/S0218127423500785","url":null,"abstract":"Epileptic seizures have spatial features related to the propagation of seizure waves. As the main characteristic of absence seizures, 2–4[Formula: see text]Hz spike-wave discharges (SWDs) originate from the cortices and are maintained by the thalamus. In this study, we explore the onset and propagation effect of absence seizures based on a thalamocortical model. First, we develop a two-compartment model and consider the autapse of the thalamic reticular nucleus as a crucial parameter to investigate transition behaviors. Moreover, we present dynamical mechanisms through bifurcation analysis. Simulation results show that the absence seizures can be induced and advanced as the coupling strength increases. Second, we investigate excitatory and inhibitory coupling functions in a three-compartment model. Our research indicates that the excitatory coupling function can lead to SWDs when all the compartments are initially saturated. In the process of propagation, excitatory coupling also gives rise to SWDs in normal compartments, whereas inhibitory coupling plays a limited role. Finally, we reproduce the above results in a 10-compartment model and verify the robustness against the variation of the number of modules. This work may shed new light on the field of seizure propagation and provide potential dynamical mechanisms.","PeriodicalId":13688,"journal":{"name":"Int. J. Bifurc. Chaos","volume":null,"pages":null},"PeriodicalIF":0.0,"publicationDate":"2023-06-15","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"91102788","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":0,"RegionCategory":"","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}

引用次数: 0

Existence, Number and Stability of Periodic Orbits Induced by Homoclinic Loops in Three-Dimensional Piecewise Linear Systems with an Admissible Saddle-Focus 具有可容许鞍焦点的三维分段线性系统中同斜环诱导周期轨道的存在性、数量和稳定性

Int. J. Bifurc. Chaos Pub Date : 2023-06-15 DOI: 10.1142/s0218127423500839

Lei Wang, Xiao-Song Yang

引用次数: 0

Nonexistence and Uniqueness of Limit Cycles in a Class of Three-Dimensional Piecewise Linear Differential Systems 一类三维分段线性微分系统极限环的不存在唯一性

Int. J. Bifurc. Chaos Pub Date : 2023-05-01 DOI: 10.1142/s021812742350075x

Ting Chen, Lihong Huang, J. Llibre

引用次数: 0

DNA Image Encryption Scheme Based on a Chaotic LSTM Pseudo-Random Number Generator 基于混沌LSTM伪随机数生成器的DNA图像加密方案

Int. J. Bifurc. Chaos Pub Date : 2023-05-01 DOI: 10.1142/s0218127423500670

K. Koubaâ, N. Derbel

{"title":"DNA Image Encryption Scheme Based on a Chaotic LSTM Pseudo-Random Number Generator","authors":"K. Koubaâ, N. Derbel","doi":"10.1142/s0218127423500670","DOIUrl":"https://doi.org/10.1142/s0218127423500670","url":null,"abstract":"Deoxyribonucleic Acid (DNA) coding technology is a new research field developed by the combination of computer science and molecular biology, that has been gradually applied in the field of image encryption in recent years. Furthermore, sensitivity to initial conditions, pseudo-random properties, and state ergodicity of coupled chaotic maps can help produce good pseudo-random number generators and meet the requirements of an image encryption system well. In this paper, an image encryption algorithm based on high-dimensional coupled chaotic maps and DNA coding is proposed. A pseudo-random sequence is generated by a long short-term memory (LSTM) architecture using the proposed maps and evaluated through a set of statistical tests to show the high performance of the proposed generator. All intensity values of an input image are converted to a binary sequence, which is scrambled globally by the high-dimensional coupled chaotic maps. The DNA operations are performed on the scrambled binary sequences instead of binary operations to increase the algorithm efficiency. Simulation results and performance analyses demonstrate that the proposed encryption scheme is extremely sensitive to small changes in secret keys, provides high security and can resist differential attack.","PeriodicalId":13688,"journal":{"name":"Int. J. Bifurc. Chaos","volume":null,"pages":null},"PeriodicalIF":0.0,"publicationDate":"2023-05-01","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"90600318","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":0,"RegionCategory":"","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}

引用次数: 0

Spin Chaos Dynamics in Classical Random Dipolar Interactions 经典随机偶极相互作用中的自旋混沌动力学

Int. J. Bifurc. Chaos Pub Date : 2023-05-01 DOI: 10.1142/s0218127423500724

M. Momeni

引用次数: 0