Int. J. Bifurc. Chaos最新文献_第10页

Inherent Complexity and Early Warning of Zaozhuang Circular Economy System 枣庄市循环经济系统的内在复杂性与预警

Int. J. Bifurc. Chaos Pub Date : 2023-03-30 DOI: 10.1142/s0218127423500402

Junhai Ma, Dexia Wang, Xiao Li, Bingnan Zhang

引用次数: 0

Functional Responses of Autaptic Neural Circuits to Acoustic Signals 自适应神经回路对声信号的功能响应

Int. J. Bifurc. Chaos Pub Date : 2023-03-30 DOI: 10.1142/s0218127423300094

Zhigang Zhu, Xiaofeng Zhang, Yisen Wang, Jun Ma

{"title":"Functional Responses of Autaptic Neural Circuits to Acoustic Signals","authors":"Zhigang Zhu, Xiaofeng Zhang, Yisen Wang, Jun Ma","doi":"10.1142/s0218127423300094","DOIUrl":"https://doi.org/10.1142/s0218127423300094","url":null,"abstract":"It is important for functional neurons of animals or human beings to adapt to external stimuli, such as sound, pressure, and light. Regarding this aspect, autaptic neuron enables itself to utilize historical information to modulate its instant dynamics, such that it may be able to behave adaptively. In this paper, a FitzHugh–Nagumo based autaptic neuron is employed to investigate the capability of a sound-sensitive neural circuit’s adaptation and filtering to analog acoustic signals. Extensive simulations are performed for excitatory and inhibitory types of autaptic neurons. The results show that the time-delayed feedback of the excitatory chemical autapse can be tuned to play the role of a narrow-band filter in response to a broadband acoustic signal. While the excitatory chemical autaptic neuron cannot saturate its response amplitude due to its positive feedback gain, the inhibitory chemical autapse can drive the neuron’s amplitude to converge as the intensity of external drive increases, which reveals the capability of adaptation. What’s more, the inhibitory chemical autaptic neuron can also exhibit a novel bursting adaptation, in which the number of spikings contained in one bursting changes as the electrical activity evolves. For electrical autaptic neurons, it is also found that both time-delay feedback gains can effectively modulate the response of neuron to acoustic signal. While the variation of time-lags mainly changes the spiking rates of the excitatory electrical autaptic neuron, the feedback gain alters its response amplitude. Lastly, by carefully tuning the time-lags, the expected subthreshold dynamics for larger inhibitory feedback gains can be switched to nearby quasi-periodic firings, which implies a competing relation between the time-delays and the feedback gains in the spiking dynamics of the inhibitory electrical autaptic neurons. The diverse emerging phenomena are expected to facilitate the design of online or interactive learning artificial neural networks with these functional autaptic neurons.","PeriodicalId":13688,"journal":{"name":"Int. J. Bifurc. Chaos","volume":null,"pages":null},"PeriodicalIF":0.0,"publicationDate":"2023-03-30","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"74632294","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

DPI DCSK Modulation with BCJR Decoding DPI DCSK调制与BCJR解码

Int. J. Bifurc. Chaos Pub Date : 2023-03-30 DOI: 10.1142/s0218127423500426

Ziqiang Zhu, Pingping Chen, Zhijian Lin, Haoyu Chen, Yi Fang, Yong Li

{"title":"DPI DCSK Modulation with BCJR Decoding","authors":"Ziqiang Zhu, Pingping Chen, Zhijian Lin, Haoyu Chen, Yi Fang, Yong Li","doi":"10.1142/s0218127423500426","DOIUrl":"https://doi.org/10.1142/s0218127423500426","url":null,"abstract":"This paper proposes a novel [Formula: see text]-ary differential permutation index (DPI) differential chaos shift keying (DCSK) by using the Bahl–Cocke–Jeline–Raviv (BCJR) decoding (DPI-DCSK-BCJR) for chaos-based communications. By exploiting the characteristics of differential modulation and quasi-orthogonality of chaotic signals, the proposed DPI-DCSK-BCJR can provide two more calculated energies to decide the transmitted bits. Theoretical analysis of bit-error-rate (BER) is carried out over multipath Rayleigh fading channel and then validated via simulations. The proposed scheme is demonstrated to outperform the conventional DPI-DCSK by 2[Formula: see text]dB for different [Formula: see text]. This performance gain is especially increased over high-delay channels. Furthermore, the advantage of the proposed frequency-modulated DPI-DCSK-BCJR is verified over practical ultra-wideband (UWB) wireless channels. In addition, we investigate the proposed DPI-DCSK-BCJR for more generalized multiuser communications. The simulation result shows that DPI-DCSK-BCJR can achieve performance gains up to 5[Formula: see text]dB as compared to the conventional PI-DCSK and DPI-DCSK for both two and three user systems. Consequently, the proposed DPI-DCSK-BCJR can be considered as a low-cost alternative for low-complexity and high-rate chaotic-based wireless communication.","PeriodicalId":13688,"journal":{"name":"Int. J. Bifurc. Chaos","volume":null,"pages":null},"PeriodicalIF":0.0,"publicationDate":"2023-03-30","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"76684928","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

Dynamic Survivability in Nonlinear Oscillation Systems with Attractive-Repulsive Interaction 具有吸引-排斥相互作用的非线性振荡系统的动态生存性

Int. J. Bifurc. Chaos Pub Date : 2023-03-30 DOI: 10.1142/s0218127423500499

Yuexin Wang, Zhongkui Sun, Shutong Liu, Yining Zhou, Wei Xu

引用次数: 0

Classification on Boundary-Equilibria and Singular Continuums of Continuous Piecewise Linear Systems 连续分段线性系统的边界平衡和奇异连续的分类

Int. J. Bifurc. Chaos Pub Date : 2023-03-30 DOI: 10.1142/s0218127423500517

Hebai Chen, Zhaosheng Feng, Hao Yang, Linfeng zhou

引用次数: 0

Nonlinear Vibration of Bolted Rotor Bearing System Accounting for the Bending Stiffness Characteristics of the Connection Interface 考虑连接界面弯曲刚度特性的螺栓转子轴承系统非线性振动

Int. J. Bifurc. Chaos Pub Date : 2023-03-30 DOI: 10.1142/s0218127423500505

Wujiu Pan, Liangyu Ling, Haoyong Qu, Minghai Wang

{"title":"Nonlinear Vibration of Bolted Rotor Bearing System Accounting for the Bending Stiffness Characteristics of the Connection Interface","authors":"Wujiu Pan, Liangyu Ling, Haoyong Qu, Minghai Wang","doi":"10.1142/s0218127423500505","DOIUrl":"https://doi.org/10.1142/s0218127423500505","url":null,"abstract":"This paper considers the discontinuous characteristics of a real aero-engine rotor system, that is, the existence of bolted connection characteristics, and establishes a new bolted connection rotor system model. Taking into account the bending stiffness and the nonlinear Hertzian contact force of the rolling bearing, the Newmark-[Formula: see text] numerical method is used to solve the system response, and the influence of the bending stiffness on the system is studied. Moreover, the effects of bending stiffness and eccentricity on the system dynamics are analyzed. The results show that the nonlinear phenomena of the system are more abundant and the critical speed of the system is higher when the bending stiffness is involved. With the increase of bending stiffness, the critical speed of the system increases, and the frequency component of the system becomes more complex. Then, the influence of eccentricity on the system is studied based on the bending stiffness. It is found that the greater the eccentricity, the greater the critical speed of the rotor and the greater the amplitude of the main frequency. In the case of the same eccentricity, the main frequency increases as the rotational speed increases, and the frequency doubling component appears in the 2-period motion. This paper provides a basis for predicting the nonlinear response of bolted rotor-bearing system.","PeriodicalId":13688,"journal":{"name":"Int. J. Bifurc. Chaos","volume":null,"pages":null},"PeriodicalIF":0.0,"publicationDate":"2023-03-30","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"76204730","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: 1

Parametrically Excited Nonlinear Pneumatic Artificial Muscle Under Hard Excitation: A Theoretical and Experimental Investigation 硬激励下参数激励非线性气动人工肌肉的理论与实验研究

Int. J. Bifurc. Chaos Pub Date : 2023-03-30 DOI: 10.1142/s0218127423300082

Bhaben Kalita, S. K. Dwivedy

引用次数: 0

Chaos Robustness and Computation Complexity of Piecewise Linear and Smooth Chaotic Chua's System 分段线性光滑混沌Chua系统的混沌鲁棒性和计算复杂度

Int. J. Bifurc. Chaos Pub Date : 2023-03-30 DOI: 10.1142/s0218127423500487

D. Vinko, K. Miličević, Ivan Vidovic, Bruno Zoric

{"title":"Chaos Robustness and Computation Complexity of Piecewise Linear and Smooth Chaotic Chua's System","authors":"D. Vinko, K. Miličević, Ivan Vidovic, Bruno Zoric","doi":"10.1142/s0218127423500487","DOIUrl":"https://doi.org/10.1142/s0218127423500487","url":null,"abstract":"Chaotic systems are often considered to be a basis for various cryptographic methods due to their properties, which correspond to cryptographic properties like confusion, diffusion and algorithm (attack) complexity. In these kinds of applications, chaos robustness is desired. It can be defined by the absence of periodic windows and coexisting attractors in some neighborhoods of the parameter space. On the other hand, when used as a basis for neuromorphic modeling, chaos robustness is to be avoided, and the edge-of-chaos regime is needed. This paper analyses the robustness and edge-of-chaos for Chua’s systems, comprising either a piecewise linear or a smooth function nonlinearity, using a novel figure of merit based on correlation coefficient and Lyapunov exponent. Calculation complexity, which is important when a chaotic system is implemented, is evaluated for double and decimal data types, where needed calculation time varies by a factor of about 1500, depending on the nonlinearity function and the data type. On the other hand, different data types result in different number precision, which has some practical advantages and drawbacks presented in the paper.","PeriodicalId":13688,"journal":{"name":"Int. J. Bifurc. Chaos","volume":null,"pages":null},"PeriodicalIF":0.0,"publicationDate":"2023-03-30","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"88983364","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

Weak Centers and Local Bifurcation of Critical Periods in a Z2-Equivariant Vector Field of Degree 5 5次z2等变向量场中临界周期的弱中心和局部分岔

Int. J. Bifurc. Chaos Pub Date : 2023-03-15 DOI: 10.1142/s0218127423500293

Yusen Wu, Feng Li

引用次数: 0

The Darboux Polynomials and Integrability of Polynomial Levinson-Smith Differential Equations 多项式Levinson-Smith微分方程的达布多项式和可积性

Int. J. Bifurc. Chaos Pub Date : 2023-03-15 DOI: 10.1142/s0218127423500359

M. Demina

引用次数: 0