周绍磊 , 赵学远 , 祁亚辉 , 等 . 有向切换拓扑条件下考虑暂态响应的多智能体 H ∞ 一致性控制 [J ] . 兵工学报 , 2020 , 41 ( 2 ): 356 - 365 . DOI: 10.3969/j.issn.1000-1093.2020.02.018 http://doi.org/10.3969/j.issn.1000-1093.2020.02.018 针对有向切换拓扑多智能体系统带领导者的一致性追踪问题，研究了H_∞一致性控制方法。通过带有领导者的Laplacian矩阵，将带领导者的一致性追踪问题转化成低维系统的稳定性问题，并给出满足暂态性能指标的充分条件；利用Lyapunov函数法并结合线性矩阵不等式方法，对系统进行了稳定性分析，得到了分布式控制器的设计方法和平均驻留时间条件。该设计方法能够使系统受到随机外部扰动时，系统状态以较小的振荡快速趋于一致，满足暂态响应性能指标。分别在考虑暂态响应、不考虑暂态响应和不受外部扰动3种条件下，对多无人机系统进行了仿真。结果表明，考虑暂态响应的H_∞一致性控制器能够使系统达成一致，比不考虑暂态响应所设计的控制器能更快地、更平稳地趋于一致，满足暂态性能指标。

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YAO D Y , LI H Y , LU R Q , et al. Distributed sliding-mode tracking control of second-order nonlinear multiagent systems: an event-triggered approach [J ] . IEEE Transactions on Cybernetics , 2020 , 50 ( 9 ): 3892 - 3902 . DOI: 10.1109/TCYB.2019.2963087 http://doi.org/10.1109/TCYB.2019.2963087 The event-triggered tracking control problem of second-order multiagent systems in consideration of system nonlinearities is investigated by utilizing the distributed sliding-mode control (SMC) approach. An event-triggered strategy is proposed to decrease the controller sampling frequency and save the network communication resources; the triggering condition is then established for leader-following multiagent systems. In this article, by utilizing the distributed event-based sliding-mode controller, the system state of second-order multiagent systems with system nonlinearities is capable of approaching the integral sliding-mode surface in finite time. A novel integral sliding-mode surface is constructed in this article to guarantee the consensus tracking performance in the existence of system nonlinearities as the state trajectories of second-order integrator systems move on the constructed sliding manifold. By employing the Lyapunov approach, sufficient conditions are deduced to ensure that the consensus tracking performance is obtained for the closed-loop system. Furthermore, it is presented that the triggering scheme can effectively reduce state updates and eliminate the Zeno behavior. A simulation example is provided to testify the validity of our proposed methodology.

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ZHAO M , GU C , ZHAO L , et al. Fixed-time leader-following consensus tracking control for nonlinear multi-agent systems under jointly connected graph [J ] . Entropy , 2022 , 24 ( 8 ): 1 - 13 . DOI: 10.3390/e24010001 http://doi.org/10.3390/e24010001 https://www.mdpi.com/1099-4300/24/1/1 https://www.mdpi.com/1099-4300/24/1/1 In this paper, we propose a new approach to train a deep neural network with multiple intermediate auxiliary classifiers, branching from it. These ‘multi-exits’ models can be used to reduce the inference time by performing early exit on the intermediate branches, if the confidence of the prediction is higher than a threshold. They rely on the assumption that not all the samples require the same amount of processing to yield a good prediction. In this paper, we propose a way to train jointly all the branches of a multi-exit model without hyper-parameters, by weighting the predictions from each branch with a trained confidence score. Each confidence score is an approximation of the real one produced by the branch, and it is calculated and regularized while training the rest of the model. We evaluate our proposal on a set of image classification benchmarks, using different neural models and early-exit stopping criteria.

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SONG G , SHI P , AGRWAL R K . Fixed-time sliding mode cooperative control for multiagent networks via event-triggered strategy [J ] . International Journal of Robust and Nonlinear Control , 2021 , 31 ( 1 ): 21 - 36 . DOI: 10.1002/rnc.v31.1 http://doi.org/10.1002/rnc.v31.1 https://onlinelibrary.wiley.com/toc/10991239/31/1 https://onlinelibrary.wiley.com/toc/10991239/31/1

LI X , YU Z Y , JIANG H J . Event-triggered fixed-time integral sliding mode control for nonlinear multi-agent systems with disturbances [J ] . Entropy , 2021 , 23 ( 11 ): 1 - 18 . DOI: 10.3390/e23010001 http://doi.org/10.3390/e23010001 https://www.mdpi.com/1099-4300/23/1/1 https://www.mdpi.com/1099-4300/23/1/1 For ensuring the safety and reliability of high-speed trains, fault diagnosis (FD) technique plays an important role. Benefiting from the rapid developments of artificial intelligence, intelligent FD (IFD) strategies have obtained much attention in the field of academics and applications, where the qualitative approach is an important branch. Therefore, this survey will present a comprehensive review of these qualitative approaches from both theoretical and practical aspects. The primary task of this paper is to review the current development of these qualitative IFD techniques and then to present some of the latest results. Another major focus of our research is to introduce the background of high-speed trains, like the composition of the core subsystems, system structure, etc., based on which it becomes convenient for researchers to extract the diagnostic knowledge of high-speed trains, where the purpose is to understand how to use these types of knowledge. By reasonable utilization of the knowledge, it is hopeful to address various challenges caused by the coupling among subsystems of high-speed trains. Furthermore, future research trends for qualitative IFD approaches are also presented.

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WEN L Z , YU S H , ZHAO Y , et al. Finite-time dynamic event-triggered consensus of multi-agent systems with disturbances via integral sliding mode [J ] . International Journal of Control , 2021 . DOI: 10.1080/00207179.2021.1989045 https://dx.doi.org/10.1080/00207179.2021.1989045 . DOI: 10.1080/00207179.2021.1989045 http://doi.org/10.1080/00207179.2021.1989045

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孙梦薇 , 任璐 , 刘剑 , 等 . 切换拓扑下动态事件触发多智能体系统固定时间一致性 [J ] . 自动化学报 , 2022 , 48 ( 4 ): 1 - 11 .

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