Nonlinear Analysis-Hybrid Systems最新文献_第2页

Stabilization of unstable impulsive systems via stochastic discrete-time feedback control with Lévy noise 带lsamvy噪声的不稳定脉冲系统的随机离散反馈镇定

IF 3.7 2区计算机科学

Nonlinear Analysis-Hybrid Systems Pub Date : 2025-02-22 DOI: 10.1016/j.nahs.2025.101585

Mengmeng Zhang, Quanxin Zhu

引用次数: 0

Reachability analysis of recurrent neural networks 递归神经网络的可达性分析

IF 3.7 2区计算机科学

Nonlinear Analysis-Hybrid Systems Pub Date : 2025-02-21 DOI: 10.1016/j.nahs.2025.101581

Sung Woo Choi , Yuntao Li , Xiaodong Yang , Tomoya Yamaguchi , Bardh Hoxha , Georgios Fainekos , Danil Prokhorov , Hoang-Dung Tran

{"title":"Reachability analysis of recurrent neural networks","authors":"Sung Woo Choi , Yuntao Li , Xiaodong Yang , Tomoya Yamaguchi , Bardh Hoxha , Georgios Fainekos , Danil Prokhorov , Hoang-Dung Tran","doi":"10.1016/j.nahs.2025.101581","DOIUrl":"10.1016/j.nahs.2025.101581","url":null,"abstract":"<div><div>The paper proposes a new sparse star set representation and extends the recent star reachability method to verify the robustness of vanilla, long short-term memory (LSTM), and gated recurrent units (GRU) recurrent neural networks (RNNs) for safety-critical applications. RNNs are a popular machine learning method for various applications, but they are vulnerable to adversarial attacks, where slightly perturbing the input sequence can lead to an unexpected result. Recent notable techniques for verifying RNNs include unrolling and invariant inference approaches. The first method has scaling issues since unrolling an RNN creates a large feedforward neural network. The second method, using invariant sets, has better scalability but can produce unknown results due to the accumulation of over-approximation errors over time. This paper introduces a complementary verification method for RNNs that is both sound and complete. A relaxation parameter can be used to convert the method into a fast over-approximation method that still provides soundness guarantees. The vanilla RNN verification method is designed to be used with NNV, a tool for verifying deep neural networks and learning-enabled cyber–physical systems, while the verification approach of LSTM and GRU RNNs are implemented on <em>StarV</em>. Compared to state-of-the-art methods for verifying a vanilla RNN, the extended exact reachability method is <span><math><mrow><mn>10</mn><mo>×</mo></mrow></math></span> faster, and the over-approximation method is <span><math><mrow><mn>100</mn><mo>×</mo></mrow></math></span> to <span><math><mrow><mn>5000</mn><mo>×</mo></mrow></math></span> faster. Although the sparse star set is slow compared to state-of-the-art methods, it was able to verify more robust cases in general than them.</div></div>","PeriodicalId":49011,"journal":{"name":"Nonlinear Analysis-Hybrid Systems","volume":"56 ","pages":"Article 101581"},"PeriodicalIF":3.7,"publicationDate":"2025-02-21","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"143453561","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":2,"RegionCategory":"计算机科学","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}

引用次数: 0

Chaotic dynamics of three-dimensional piecewise linear systems with sliding heteroclinic cycles 具有滑动异斜周期的三维分段线性系统的混沌动力学

IF 3.7 2区计算机科学

Nonlinear Analysis-Hybrid Systems Pub Date : 2025-02-13 DOI: 10.1016/j.nahs.2025.101584

Zhe Zhao, Tiantian Wu

引用次数: 0

Recurrent output tracking of Boolean networks 布尔网络的循环输出跟踪

IF 3.7 2区计算机科学

Nonlinear Analysis-Hybrid Systems Pub Date : 2025-02-13 DOI: 10.1016/j.nahs.2025.101583

Chunfeng Jiang , Shihua Fu , Carmen Del Vecchio , Biao Wang , Jianjun Wang , Jianli Zhao

引用次数: 0

Bifurcation analysis and sliding mode control of a singular piecewise-smooth prey–predator model with distributed delay 具有分布式延迟的奇异片滑捕食者-捕食者模型的分岔分析和滑模控制

IF 3.7 2区计算机科学

Nonlinear Analysis-Hybrid Systems Pub Date : 2025-02-12 DOI: 10.1016/j.nahs.2025.101582

Yue Zhang, Xin Ai, Zhenlei Li, Jie Gao

{"title":"Bifurcation analysis and sliding mode control of a singular piecewise-smooth prey–predator model with distributed delay","authors":"Yue Zhang, Xin Ai, Zhenlei Li, Jie Gao","doi":"10.1016/j.nahs.2025.101582","DOIUrl":"10.1016/j.nahs.2025.101582","url":null,"abstract":"<div><div>In this paper, the piecewise-smooth functional response function and distributed delay are used to describe the memory effect of predators and capture law when the abundance of prey changes greatly in ecosystems more realistically. A singular piecewise-smooth prey–predator model with distributed delay is studied. Considering the growth and loss rate of the predator much smaller than that of the prey, the model is described by a fast–slow system that mathematically leads to a singular perturbation problem. The dynamic behavior of the fast–slow system with distributed delay, piecewise smooth is novel and interesting. The system undergoes a Hopf bifurcation where the interior equilibrium becomes unstable leading to a stable limit cycle. As the perturbation parameter decreases, the co-existence equilibrium has a transition from the unstable node to the stable node which leads multiple relaxation oscillations occurring. This study reveals the occurrence of boundary equilibrium bifurcations, enriching the understanding of predator–prey dynamics. In addition, a sliding mode controller is designed in the fast–slow predator–prey system to make the periodic trajectory tend to the internal equilibrium point. Taking the predator–prey relationship between insect and bird as an example, numerical simulations are provided to verify the theoretical results.</div></div>","PeriodicalId":49011,"journal":{"name":"Nonlinear Analysis-Hybrid Systems","volume":"56 ","pages":"Article 101582"},"PeriodicalIF":3.7,"publicationDate":"2025-02-12","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"143387469","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":2,"RegionCategory":"计算机科学","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}

引用次数: 0

Stationary distribution and sliding mode control on a stochastic hybrid epidemic model with telegraph noise 带电报噪声的随机混合流行病模型的平稳分布与滑模控制

IF 3.7 2区计算机科学

Nonlinear Analysis-Hybrid Systems Pub Date : 2025-02-10 DOI: 10.1016/j.nahs.2025.101580

Xiju Wu , Yue Zhang , Xinzhu Yan

引用次数: 0

Privacy-preserving resilient bipartite consensus of multi-agent systems: A differential privacy scheme 多智能体系统的隐私保护弹性二部共识：一种差分隐私方案

IF 3.7 2区计算机科学

Nonlinear Analysis-Hybrid Systems Pub Date : 2025-02-06 DOI: 10.1016/j.nahs.2025.101579

Ran Tian, Jie Mei, Guangfu Ma

引用次数: 0

Sure robust global versus robust global almost sure convergence: Implementing a dynamic random coefficient selection in a quaternion-hysteresis-based distributed hybrid algorithm 鲁棒全局与鲁棒全局几乎肯定收敛：在基于四元数-滞后的分布式混合算法中实现动态随机系数选择

IF 3.7 2区计算机科学

Nonlinear Analysis-Hybrid Systems Pub Date : 2025-01-31 DOI: 10.1016/j.nahs.2025.101578

Dandan Zhang , Xin Jin , Hongye Su

{"title":"Sure robust global versus robust global almost sure convergence: Implementing a dynamic random coefficient selection in a quaternion-hysteresis-based distributed hybrid algorithm","authors":"Dandan Zhang , Xin Jin , Hongye Su","doi":"10.1016/j.nahs.2025.101578","DOIUrl":"10.1016/j.nahs.2025.101578","url":null,"abstract":"<div><div>By employing Lyapunov-like conditions along with the stochastic invariance principle, we develop a quaternion-hysteresis-based distributed stochastic hybrid feedback algorithm aimed at achieving robust <em>global</em> attitude synchronization, addressing both <em>sure</em> and <em>almost sure</em> convergence. The distributed hybrid algorithm integrates a hybrid control variable that experiences continuous changes and instantaneous resets according to a unit quaternion-based reset rule and the associated hysteresis-based conditions. In this hysteresis-based hybrid framework, by treating the reset coefficients as random variables, these coefficients introduce the unique source of randomness; these coefficients are dynamically and randomly selected by the reset rule, leading to varying hysteresis half-widths and, consequently, different nominal levels of robustness; the orientation of the spring force, which reversely pulls the rigid body along the rotation axis to prevent the unwinding phenomenon, is determined by the deterministic sign of the hybrid control variable, whereas the hysteresis half-widths can delay this pulling. By dynamically and randomly adjusting the stochastic hysteresis half-widths, we create a flexible tradeoff between mitigating the amount of unwinding and enhancing the nominal level of robustness to measurement noise. By imposing different constraints on the support domain of random reset coefficients, the hybrid algorithm achieves both <em>sure</em> robust <em>global</em> and robust <em>global almost sure</em> attitude synchronization.</div></div>","PeriodicalId":49011,"journal":{"name":"Nonlinear Analysis-Hybrid Systems","volume":"56 ","pages":"Article 101578"},"PeriodicalIF":3.7,"publicationDate":"2025-01-31","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"143144670","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":2,"RegionCategory":"计算机科学","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}

引用次数: 0

STL and wSTL control synthesis: A disjunction-centric mixed-integer linear programming approach STL和wSTL控制综合：一种以析取为中心的混合整数线性规划方法

IF 3.7 2区计算机科学

Nonlinear Analysis-Hybrid Systems Pub Date : 2025-01-29 DOI: 10.1016/j.nahs.2025.101576

Gustavo A. Cardona, Disha Kamale, Cristian-Ioan Vasile

{"title":"STL and wSTL control synthesis: A disjunction-centric mixed-integer linear programming approach","authors":"Gustavo A. Cardona, Disha Kamale, Cristian-Ioan Vasile","doi":"10.1016/j.nahs.2025.101576","DOIUrl":"10.1016/j.nahs.2025.101576","url":null,"abstract":"<div><div>This paper introduces an efficient optimization-based control synthesis methodology tailored for Signal Temporal Logic (STL) and its extension, weighted Signal Temporal Logic (wSTL). While STL captures Boolean and temporal operators, wSTL further allows users to express preferences and priorities over concurrent and sequential tasks denoted by weights over logical and temporal operators along with satisfaction times. The proposed approach utilizes Mixed Integer Linear Programming (MILP) for synthesis with both STL and wSTL formulae. We introduce efficient disjunction-centric encodings for STL and wSTL that capture both qualitative and quantitative semantics. This encoding minimizes the number of variables and constraints necessary to represent STL and wSTL formulae by efficiently handling conjunction operations (e.g., conjunction, always operators) and only introducing variables when disjunction operations are used (e.g., disjunction, eventually). Multiple case studies are conducted to demonstrate the proposed methodology’s operation and computational efficiency for the control synthesis with STL and wSTL specifications. While non-linear dynamics and predicates can be considered using piecewise linear functions, this work focuses on linear predicates and dynamics. We show how cost functions involving potentially conflicting objectives expressed in terms of states, controls, and satisfaction robustness impact the solutions to the control synthesis problem for STL and wSTL. We conduct a sensitivity analysis of weights used in wSTL formulae, offering detailed insights into how these weights modulate solutions for given formulae. Finally, the time performance of the disjunction-centric encodings for both STL and wSTL is compared against state-of-the-art frameworks, comprehensively evaluating their efficiency and practical applicability.</div></div>","PeriodicalId":49011,"journal":{"name":"Nonlinear Analysis-Hybrid Systems","volume":"56 ","pages":"Article 101576"},"PeriodicalIF":3.7,"publicationDate":"2025-01-29","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"143144667","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":2,"RegionCategory":"计算机科学","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"OA","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}

引用次数: 0

Multiple circles formation-circumnavigation switching control around a nonstationary target 非静止目标多圆编队-绕航切换控制

IF 3.7 2区计算机科学

Nonlinear Analysis-Hybrid Systems Pub Date : 2025-01-25 DOI: 10.1016/j.nahs.2025.101577

Bo Chen, Wei Zhu

{"title":"Multiple circles formation-circumnavigation switching control around a nonstationary target","authors":"Bo Chen, Wei Zhu","doi":"10.1016/j.nahs.2025.101577","DOIUrl":"10.1016/j.nahs.2025.101577","url":null,"abstract":"<div><div>In this study, the problem of multiple circles formation-circumnavigation switching control around a nonstationary target of multiple heterogeneous autonomous underwater vehicle (AUV) systems with intermittent communication among partial individuals is investigated. An intermittent communication-based two-layer control strategy is proposed, comprising finite time observers and finite time controller. Since the communication between individuals is intermittent and only partial AUVs can directly obtain partial information from the target, a distributed adaptive finite-time hybrid observer is designed to estimate the information of the target. Additionally, another observer is developed to estimate the state of cluster leader. Subsequently, based on geometric structure and variable substitution, a distributed finite-time multiple circles formation-circumnavigation switching controller is designed, using the estimated value as the reference signal. The controller enables smooth switching between formation and circumnavigation for multiple AUV systems in intermittent communication scenarios, which can effectively improve the economy and practicality of applications. A homogeneous technique is used to show that the control objective can be achieved in finite time under the proposed controller. Numerical simulations are conducted to illustrate the effectiveness of the proposed control strategy.</div></div>","PeriodicalId":49011,"journal":{"name":"Nonlinear Analysis-Hybrid Systems","volume":"56 ","pages":"Article 101577"},"PeriodicalIF":3.7,"publicationDate":"2025-01-25","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"143144666","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":2,"RegionCategory":"计算机科学","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}

引用次数: 0