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IEEE/CAA Journal of Automatica Sinica 2021年第1期8卷 77-85页

作者： Xian-ming zhang Qing-long Han Xiaohua Ge the School of Software and Electrical Engineering Swinburne University of TechnologyMelbourneVIC 3122Australia

One of challenging issues on stability analysis of time-delay systems is how to obtain a stability criterion from a matrix-valued polynomial on a time-varying *** first contribution of this paper is to establish a necessary and sufficient condition on a matrix-valued polynomial inequality over a certain closed *** degree of such a matrix-valued polynomial can be an arbitrary finite positive *** second contribution of this paper is to introduce a novel LyapunovKrasovskii functional,which includes a cubic polynomial on a time-varying delay,in stability analysis of time-delay *** on the novel Lyapunov-Krasovskii functional and the necessary and sufficient condition on matrix-valued polynomial inequalities,two stability criteria are derived for two cases of the time-varying delay.A well-studied numerical example is given to show that the proposed stability criteria are of less conservativeness than some existing ones.

关键词： Bessel-Legendre inequality matrix-valued polynomial inequalities stability time-varying delay time-delay systems

Enhanced Reproducibility of Positive Temperature Coefficient Effect of CB/HDPE/PVDF Composites with the Addition of Ionic Liquid

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Chinese Journal of Polymer Science 2021年第2期39卷 228-236,I0008页

作者： long Chen Xiao Wu Xiao-Fang zhang Jian-ming zhang Key Laboratory of Rubber-Plastics Ministry of Education/Shandong Provincial Key Laboratory of Rubber-plasticsQingdao University of Science&TechnologyQingdao 266042China

Developing an effective method for improving the reproducibility of positive temperature coefficient(PTC)effect is of great significance for large-scale application of polymer based PTC composites,owing to its contribution to the security and ***,we developed a carbon black(CB)/high density polyethylene(HDPE)/poly(vinylidene fluoride)(PVDF)composite with outstanding PTC reproducibility,by incorporating 1-octyl-3-methylimidazolium bis(trifluoromethylsulfonyl)imide([OMIm][NTf2])into the *** multiple repeated temperature cycles,the PTC performance of as-prepared material keeps almost unchanged and the varition of resistance at room temperature is less than 7%.Our studies revealed that[OMIm][NTf2]contributes to the improvement of PTC reproducibility in two ways:(i)it acts as an efficient plasticizer for refining the co-continuous phase morphology of HDPE/PVDE blends;(ii)it inhibits the crystallization of PVDF through the dilution effect,leading to more overlaps of the volume shrinkage process of HDPE and PVDF melt which results in the decrease of interface gap between HDPE and *** study demonstrated that ionic liquids as the multifunctional agents have great potential for improving the reproducibility in the application of the binary polymer based PTC composites.

关键词： Conductive polymer composites Reproducibility Positive temperature coefficient Ionic liquid

Glucocorticoid receptor signaling in the brain and its involvement in cognitive function

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Neural Regeneration Research 2025年第9期20卷 2520-2537页

作者： Chonglin Su Taiqi Huang Meiyu zhang Yanyu zhang Yan Zeng Xingxing Chen Brain Science and Advanced Technology Institute Hubei Province Key Laboratory of Occupational Hazard Identification and ControlSchool of MedicineWuhan University of Science and TechnologyWuhanHubei ProvinceChina

The hypothalamic-pituitary-adrenal axis regulates the secretion of glucoco rticoids in response to environmental *** the brain,a nuclear receptor transcription fa ctor,the glucocorticoid recepto r,is an important component of the hypothalamicpituitary-a d renal axis's negative feedback loop and plays a key role in regulating cognitive equilibrium and *** glucoco rticoid receptor influences cognitive processes,including glutamate neurotransmission,calcium signaling,and the activation of brain-derived neurotrophic factor-mediated pathways,through a combination of genomic and non-genomic *** interactions within the central nervous system can alter the expression and activity of the glucocorticoid receptor,there by affecting the hypothalamic-pituitary-a d renal axis and stress-related cognitive *** appropriate level of glucocorticoid receptor expression can improve cognitive function,while excessive glucocorticoid receptors or long-term exposure to glucoco rticoids may lead to cognitive *** with cognitive impairment-associated diseases,such as Alzheimer's disease,aging,depression,Parkinson's disease,Huntington's disease,stroke,and addiction,often present with dysregulation of the hypothalamic-pituitary-adrenal axis and glucocorticoid receptor *** review provides a comprehensive overview of the functions of the glucoco rticoid receptor in the hypothalamic-pituitary-a d renal axis and cognitive *** emphasizes that appropriate glucocorticoid receptor signaling fa cilitates learning and memory,while its dysregulation can lead to cognitive *** provides clues about how glucocorticoid receptor signaling can be targeted to ove rcome cognitive disability-related disorders.

关键词： brain-derived neurotrophic factor calcium signaling glucocorticoid receptor glucocorticoid glutamate transmission hypothalamic-pituitary-adrenal axis long-term potentiation neurocognitive disorders neuroplasticity stress

Controller area network node reliability assessment based on observable node information

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Frontiers of Information Technology & Electronic Engineering 2017年第5期18卷 615-626页

作者： Lei-ming zhang long-hao TANG Yong LEI State Key Laboratory of Fluid Power Transmission and Mechatronics Zhejiang UniversityHangzhou 310027China

Controller area network(CAN) based fieldbus technologies have been widely used in networked manufacturing systems. As the information channel of the system, the reliability of the network is crucial to the system throughput, product quality, and work crew safety. However, due to the inaccessibility of the nodes' internal states, direct assessment of the reliability of CAN nodes using the nodes' internal error counters is infeasible. In this paper, a novel CAN node reliability assessment method, which uses node's time to bus-off as the reliability measure, is proposed. The method estimates the transmit error counter(TEC) of any node in the network based on the network error log and the information provided by the observable nodes whose error counters are ***, a node TEC estimation model is established based on segmented Markov chains. It considers the sparseness of the distribution of the CAN network errors. Second, by learning the differences between the model estimates and the actual values from the observable node, a Bayesian network is developed for the estimation updating mechanism of the observable nodes. Then, this estimation updating mechanism is transferred to general CAN nodes with no TEC value accessibility to update the TEC estimation. Finally, a node reliability assessment method is developed to predict the time to reach bus-off state of the nodes. Case studies are carried out to demonstrate the effectiveness of the proposed methodology. Experimental results show that the estimates using the proposed model agree well with actual observations.

关键词： Controller area network(CAN) Transmit error counter(TEC) TEC value estimation Bayesian network Bus-off hitting time

Effect of shot peening on hydrogen embrittlement of high strength steel

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International Journal of Minerals,Metallurgy and Materials 2016年第6期23卷 667-675页

作者： Xin-feng Li Jin zhang ming-ming Ma Xiao-long Song State Key Laboratory for Mechanical Behavior of Materials Xi'an Jiaotong University Department of Geosciences State University of New YorkStony Brook Department of Heat Treatment and Surface Treatment AVIC Aircraft Co. Ltd.Xi'an Break Branch

The effect of shot peening（SP） on hydrogen embrittlement of high strength steel was investigated by electrochemical hydrogen charging, slow strain rate tensile tests, and hydrogen permeation tests. Microstructure observation, microhardness, and X-ray diffraction residual stress studies were also conducted on the steel. The results show that the shot peening specimens exhibit a higher resistance to hydrogen embrittlement in comparison with the no shot peening（NSP） specimens under the same hydrogen-charging current density. In addition, SP treatment sharply decreases the apparent hydrogen diffusivity and increases the subsurface hydrogen concentration. These findings are attributed to the changes in microstructure and compressive residual stress in the surface layer by SP. Scanning electron microscope fractographs reveal that the fracture surface of the NSP specimen exhibits the intergranular and quasi-cleavage mixed fracture modes, whereas the SP specimen shows only the quasi-cleavage fractures under the same hydrogen charging conditions, implying that the SP treatment delays the onset of intergranular fracture.

关键词： high strength steel shot peening hydrogen embrittlement cracking fracture inclusions

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文明叙事:习近平文化思想的方法论审视

新疆师范大学学报（哲学社会科学版） 2025年第1期46卷 34-42页

作者：张明谷生秀南京大学马克思主义学院江苏南京210023

文明是中国共产党百余年推进马克思主义中国化时代化的核心线索,文明叙事是中国共产党历史叙事的重要维度,也是习近平文化思想的重要方法论。习近平文化思想的深厚文明意蕴体现在四个方面:一是从历史纵深出发把握“走自己的路”的文明基... 详细信息

文明是中国共产党百余年推进马克思主义中国化时代化的核心线索,文明叙事是中国共产党历史叙事的重要维度,也是习近平文化思想的重要方法论。习近平文化思想的深厚文明意蕴体现在四个方面:一是从历史纵深出发把握“走自己的路”的文明基因,即从中华5000多年文明的历史传承中把握中国道路的来龙去脉及其内在逻辑必然;二是以“第二个结合”为根本方法,重塑发展中华文明的使命担当,不断推动建设中华民族现代文明实现传统文明的现代新生;三是坚守文明超越理念,将新文明的建构与中国式现代化的现实实践相互关联,以中国式现代化创造人类文明新形态,打破西方以资本逻辑为核心的形而上学抽象文明观的历史困境;四是坚持文明交流互鉴,推动落实全球文明倡议,构建人类文明交往新范式。

关键词：习近平文化思想文明叙事 “走自己的路” “第二个结合” 文明交流互鉴

Accumulated-state-error-based event-triggered sampling scheme and its application to H∞ control of sampled-data systems

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Science China(Information Sciences) 2024年第6期67卷 328-341页

作者： Xian-ming zhang Qing-long HAN Bao-Lin zhang Xiaohua GE Dawei zhang School of Science Computingand Engineering TechnologiesSwinburne University of Technology College of Automation and Electronic Engineering Qingdao University of Science & Technology School of Mathematics Shandong University

This paper is concerned with event-triggered H∞control of sampled-data systems. Its novelties lie in three aspects:（i） A novel accumulated-state-error-based event-triggered scheme is introduced by comparing the integral of the state error from tk to t with the system state sampled at tk. This condition works well due to the fact that the so-called Zeno behaviour does not occur.（ii） A novel Lyapunov functional is constructed to establish a criterion to ensure some certain H∞performance of the closed-loop system. This Lyapunov functional is dependent on the integral of the state error involved in the event-triggered scheme.（iii） Under the event-triggered sampling scheme, suitable state-feedback controllers can be designed rather than be given a priori. Moreover, a self-triggered implementation of the proposed event-triggered sampling scheme is presented as well. Finally, a batch reactor model and an inverted pendulum system are given to demonstrate the effectiveness of the proposed method.

关键词： event-triggered sampling self-triggered implementation $H_\infty$ control looped-functional

An adaptive loop gain selection for CLEAN deconvolution algorithm

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Research in Astronomy and Astrophysics 2019年第6期19卷 37-42页

作者： Li zhang long Xu ming zhang Zhong-Zu Wu College of Big Data and Information Engineering Guizhou University Guiyang 550025 China Key Laboratory of Solar Activity National Astronomical Observatories Chinese Academy of Sciences Beijing 100101 China Xinjiang Astronomical Observatory Chinese Academy of Sciences Urumqi 830011 China Key Laboratory of Radio Astronomy Chinese Academy of Sciences Urumqi 830011 China College of Physics Guizhou University Guiyang 550025 China

Radio interferometry significantly improves the resolution of observed images, and the final result also relies heavily on data recovery. The Cotton-Schwab CLEAN(CS-Clean) deconvolution approach is a widely used reconstruction algorithm in the field of radio synthesis imaging. However, parameter tuning for this algorithm has always been a difficult task. Here, its performance is improved by considering some internal characteristics of the data. From a mathematical point of view, a peak signal-to-noise-based(PSNRbased) method was introduced to optimize the step length of the steepest descent method in the recovery process. We also found that the loop gain curve in the new algorithm is a good indicator of parameter *** show that the new algorithm can effectively solve the problem of oscillation for a large fixed loop gain and provides a more robust recovery.

关键词： methods data analysis-techniques image processing-techniques interferometric

A Scalable Adaptive Approach to Multi-Vehicle Formation Control with Obstacle Avoidance

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IEEE/CAA Journal of Automatica Sinica 2022年第6期9卷 990-1004页

作者： Xiaohua Ge Qing-long Han Jun Wang Xian-ming zhang IEEE School of Science Computing and Engineering TechnologiesSwinburne University of TechnologyMelbourneVIC 3122Australia Department of Computer Science and School of Data Science City University of Hong KongChina

This paper deals with the problem of distributed formation tracking control and obstacle avoidance of multivehicle systems(MVSs)in complex obstacle-laden *** MVS under consideration consists of a leader vehicle with an unknown control input and a group of follower vehicles,connected via a directed interaction topology,subject to simultaneous unknown heterogeneous nonlinearities and external *** central aim is to achieve effective and collisionfree formation tracking control for the nonlinear and uncertain MVS with obstacles encountered in formation maneuvering,while not demanding global information of the interaction *** this goal,a radial basis function neural network is used to model the unknown nonlinearity of vehicle dynamics in each vehicle and repulsive potentials are employed for obstacle ***,a scalable distributed adaptive formation tracking control protocol with a built-in obstacle avoidance mechanism is *** is proved that,with the proposed protocol,the resulting formation tracking errors are uniformly ultimately bounded and obstacle collision avoidance is *** simulation results are elaborated to substantiate the effectiveness and the promising collision avoidance performance of the proposed scalable adaptive formation control approach.

关键词： Adaptive control collision avoidance distributed formation control multi-vehicle systems neural networks obstacle avoidance repulsive potential