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Fault Tolerant Control for Networked Control Systems with Access Constraints

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自动化学报 2012年第7期38卷 1119-1126页

作者： zhao ming-yue LIU He-Ping LI Zhi-Jun SUN De-Hui LIU Ke-Ping Institute of Automation University of Science and Technol- ogy Beijing Beijing 100083 P.R. China School of Electrical and Electronic Engineering Changchun University of Technology Changchun 130012 P. R. China Institute of Automation North China University of Technology Beijing 100144 P.R. China

In this paper, the problem of fault tolerant control (FTC) considering actuator fault for networked control systems (NCSs) with access constraints is addressed. A static scheduling method, periodic communication sequence (PCS), is applied to allocate network resource and schedule the access to the network. The novelty of this work lies in that the NCS with PCS and actuator fault are modeled as a periodic switching system and the schedule-dependent Lyapunov function method is used to design the fault tolerant controller. For the data packets dropped by scheduling strategy at each sampling time, 0 and the value of previous sampling time are respectively considered to recover them. Additionally, the problem of robust FTC for the controlled plant with external energy-bounded disturbance is also respectively discussed under these two situations. Numerical examples are given to illustrate the effectiveness of the proposed design methods.

关键词：网络控制系统容错控制器访问限制 Lyapunov函数法执行器故障采样时间设计方法调度方法

Anchoring 1T-MoS_(2)petals on N-doped reduced graphene oxide for exceptional electromagnetic wave absorption

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International Journal of Minerals,Metallurgy and Materials 2025年第3期32卷 619-630页

作者： Jia zhao Haoran Lai ming Li College of Chemistry and Materials Engineering Bohai UniversityJinzhou 121013China Yangtze Delta Region Institute(Huzhou) University of Electronic Science and Technology of ChinaHuzhou 313001China College of Chemistry and Chemical Engineering Jishou UniversityJishou 416000China

The effective construction of electromagnetic(EM)wave absorption materials with thin matching thickness,broad bandwidth,and remarkable absorption is a great solution to EM pollution,which is a hot topic in current environmental *** this study,N-doped reduced graphene oxide(N-rGO)was first prepared using a facile hydrothermal ***,high-purity 1T-MoS_(2)petals were homogeneously anchored to the wrinkled surface of N-rGO to fabricate 1T-MoS_(2)@N-rGO *** numerous electric di-poles and profuse heterointerfaces in 1T-MoS_(2)@N-rGO would induced the multiple reflection and scattering of EM waves in a distinct-ive multidimensional structure formed by two-dimensional N-rGO and 1T-MoS_(2)microspheres with plentiful thin nanosheets,remarkable conduction loss derived from the migration of massive electrons in a well-constructed conductive network formed by 1T-MoS_(2)@N-rGO,and abundant polarization loss(including dipolar polarization loss and interfacial polarization loss).All of these gave the 1T-MoS_(2)@N-rGO nanocomposites superior EM wave absorption *** effective absorption bandwidth of 1T-MoS_(2)@N-rGO reached 6.48 GHz with a relatively thin matching thickness of 1.84 mm,and a minimum reflection loss of-52.24 dB was achieved at 3.84 ***,the radar scattering cross-section reduction value of 1T-MoS_(2)@N-rGO was up to 35.42 dB·m^(2) at 0°,which further verified the huge potential of our fabricated 1T-MoS_(2)@N-rGO nanocomposites in practical applications.

关键词： 1T-MoS_(2)@N-rGO nanocomposites conduction loss polarization loss ultrathin matching thickness electromagnetic wave absorption

Relative humidity-dependent evolution of molecular composition ofα-pinene secondary organic aerosol upon heterogeneous oxidation by hydroxyl radicals

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Journal of Environmental Sciences 2025年第2期148卷 210-220页

作者： Wei Wang Chenxi Li Huayun Xiao Ziyue Li yue zhao School of Environmental Science and Engineering Shanghai Jiao Tong UniversityShanghai 200240China

Heterogeneous oxidation by gas-phase oxidants is an important chemical transformation pathway of secondary organic aerosol(SOA)and plays an important role in controlling the abundance,properties,as well as climate and health impacts of ***,our knowledge on this heterogeneous chemistry remains *** this study,the heterogeneous oxidation ofα-pinene ozonolysis SOA by hydroxyl(OH)radicals was investigated under both low and high relative humidity(RH)conditions,with an emphasis on the evolution of molecular composition of SOA and its RH *** is found that the heterogeneous oxidation of SOA at an OH exposure level equivalent to 12 hr of atmospheric aging leads to particle mass loss of 60%at 25%RH and 95%at 90%*** heterogeneous oxidation strongly changes the molecular composition of *** dimer-to-monomer signal ratios increase dramatically with rising OH exposure,in particular under high RH conditions,suggesting that aerosol water stimulates the reaction of monomers with OH radicals more than that of *** addition,the typical SOA tracer compounds such as pinic acid,pinonic acid,hydroxy pinonic acid and dimer esters(e.g.,C17H26O8 and C19H28O7)have lifetimes of several hours against heterogeneous OH oxidation under typical atmospheric conditions,which highlights the need for the consideration of their heterogeneous loss in the estimation of monoterpene SOA concentrations using tracer-based *** study sheds lights on the heterogeneous oxidation chemistry ofmonoterpene SOA andwould help to understand their evolution and impacts in the atmosphere.

关键词： Secondary organic aerosol(SOA) Heterogeneous oxidation Chemical transformation Molecular composition Aerosol water

Optimization of transverse unidirectional scattering by morphology modification of irregular V-shaped silicon nanoantennas

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Optoelectronics Letters 2025年第3期21卷 129-135页

作者： ZENG ming zhao Feng WANG Xianghui School of Electrical and Information Engineering Tianjin University Institute of Modern Optics Tianjin Key Laboratory of Micro-scale Optical Information Science and TechnologyNankai University

A scheme based on irregular V-shaped silicon nanoantennas is proposed to optimize transverse unidirectional scattering under plane wave irradiation. Traditional methods of designing regular shapes offer fewer parameters and higher search efficiency. However, due to the limitations of regular shapes, it is challenging to meet high-precision design requirements. Irregular shape design allows for a broader range of adjustments, but the complexity of shape parameters leads to lower search efficiency and a higher likelihood of converging to local optima.

关键词： A

Robust free-base and metalated corrole radicals with reduction-induced emission

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Chinese Chemical Letters 2025年第2期36卷 426-431页

作者： Pengfei Li Chulin Qu Fan Wu Hu Gao Chengyan zhao yue zhao Zhen Shen State Key Laboratory of Coordination Chemistry Collaborative Innovation Center of Advanced MicrostructuresSchool of Chemistry and Chemical EngineeringNanjing University School of Chemistry and Materials Science Nanjing Normal University College of Materials Science and Engineering Nanjing Forestry University

Preparing free-base porphyrinoid radicals that can function as coordination ligands is a challenging task. Here we report the synthesis of a stable, free-base benzocorrole(BC) radical containing only two inner NH protons via a retro-Diels-Alder conversion. The radical character of BC was fully supported by crystallographic analysis, spectroscopic evidence, and theoretical calculations. This neutral radical ligand allowed easy insertion of Zn(Ⅱ), Ga(Ⅲ), and Pd(Ⅱ) ions to produce radical complexes. All these radicals exhibited luminescence-on responses under weak reducing atmosphere, corresponding to the conversion to their aromatic anions. The red fluorescence was observed for BC and its Zn(Ⅱ) and Ga(Ⅲ) complexes,and the near-infrared phosphorescence(>900 nm) was detected for Pd(Ⅱ) complex at room ***, Ga(Ⅲ) corrole exhibited a variation in fluorescence in response to axial coordination. Our findings provide a promising radical platform for coordination and developing novel functional materials with switchable spin and emission.

关键词： Luminescence Macrocyclic ligands Porphyrinoids Radicals Redox chemistry

Channel pruning on frequency response

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Science China(Information Sciences) 2025年第1期68卷 159-170页

作者： Hang LIN Yifan PENG Lin BIE Chenggang YAN Xibin zhao yue GAO School of Software Tsinghua University School of Automation Hangzhou Dianzi University

Network pruning has a significant role in reducing network parameters and accelerating the inference time of the network. Some existing methods prune the network based on the frequency of the data, and finally obtain a sub-network with high accuracy. However, according to our experimental analysis, different frequencies of information in the data contribute differently to the accuracy of the model, and using this information directly for pruning without making a selection will lead to incorrect results. We believe that pruning should retain the convolutional kernels in the network that process important information, while those kernels that process unimportant information should be removed. In this paper, we first investigate the meaning of each frequency band information in the spectrum and their contribution to the prediction accuracy of the network,and according to these results, we propose a new pruning method based on frequency response(PFR). Our PFR finds and removes the convolutional kernels in the network that specialize in processing unimportant information, resulting in a compact neural network model. PFR obtains significant experimental results on different datasets, for example, a 56.0% raduction of float points operations(FLOPs) on Res Net-50 and only 0.37% of Top-1 accuracy degradation on the Image Net dataset.

关键词： deep learning model compression filter pruning channel pruning frequency response

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基质吸力对全风化花岗岩抗剪强度的影响

科学技术与工程 2025年第3期25卷 924-932页

作者：王志朋刘红军武闻禹赵明月王起刚中国海洋大学环境科学与工程学院青岛266100 青岛地质工程勘察院青岛266100 青岛市勘察测绘研究院崂山分院青岛266100

在强降雨条件下,全风化花岗岩边坡岩土体饱和度增加,抗剪强度降低,易引发边坡失稳。在这一过程中,基质吸力变化是引起其抗剪强度变化的关键因素。以青岛市崂山全风化花岗岩边坡为研究对象,采用离心机试验、不排水直剪试验、X射线衍射分... 详细信息

在强降雨条件下,全风化花岗岩边坡岩土体饱和度增加,抗剪强度降低,易引发边坡失稳。在这一过程中,基质吸力变化是引起其抗剪强度变化的关键因素。以青岛市崂山全风化花岗岩边坡为研究对象,采用离心机试验、不排水直剪试验、X射线衍射分析、常规硅酸盐化学全分析试验和扫描电镜测试等手段,得到了基于Van Genuchten模型的全风化花岗岩的水土特征曲线,系统研究了基质吸力对全风化花岗岩抗剪强度的影响。研究结果表明:①全风化花岗岩土体饱和度与基质吸力呈负相关的趋势,级配较不均匀的土样排水能力较强;②抗剪强度指标受基质吸力的影响不同,黏聚力对基质吸力的变化相对于内摩擦角而言更加敏感;③全风化花岗岩土体中基质吸力与抗剪强度呈现正相关关系,基质吸力越大,抗剪能力越强。研究结果可为全风化花岗岩地区的边坡防治提供理论指导。

关键词：全风化花岗岩基质吸力抗剪强度饱和度 SWCC

氢化物发生-液体阴极辉光放电发射光谱对海水中硒、砷、汞的高灵敏定量检测

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光谱学与光谱分析 2019年第5期39卷 1359-1365页

作者：赵明月程君琪杨丙成汪正中国科学院上海硅酸盐研究所上海201899 中国科学院大学材料与光电研究中心北京100049 华东理工大学药学院上海200237

通过将氢化物发生装置与液体阴极辉光放电发射光谱仪相耦合,建立了一种定量检测海水中痕量硒、砷、汞的方法。实验对氢化物发生的载酸种类和浓度、还原剂浓度以及液体阴极辉光放电装置的放电电压、电解质种类和流速等工作条件进行了优化... 详细信息

通过将氢化物发生装置与液体阴极辉光放电发射光谱仪相耦合,建立了一种定量检测海水中痕量硒、砷、汞的方法。实验对氢化物发生的载酸种类和浓度、还原剂浓度以及液体阴极辉光放电装置的放电电压、电解质种类和流速等工作条件进行了优化,确定了联用仪器定量分析硒、砷、汞的最佳工作条件:氢化物发生载酸为5%的HCl,还原剂为1.5%的NaBH_4,液体阴极辉光放电装置的放电电压为1060V,电解质溶液为pH 1的HCl,电解液流速为2.2 mL·min^(-1)。分别选取204.0, 228.8和253.7 nm作为硒、砷、汞的分析谱线,在上述最佳工作条件下对硒、砷、汞的系列混合标准溶液进行测定,硒、砷、汞的质量浓度在2～100μg·L^(-1)范围内与其发射强度呈线性关系,线性相关系数分别为0.999 2, 0.999 4和0.998 5,其检出限分别达到0.54, 0.92和1.91μg·L^(-1),浓度为0.1 mg·L^(-1)的硒、砷、汞的信号值相对标准偏差均小于3%。与单一的液体阴极辉光放电发射光谱相比,硒、砷、汞的检出限分别降低了3个、 4个、 2个数量级。选取国家土壤标准物质GBW07405对联用仪器检测结果的准确度进行了验证,其检测值与参考值一致;将该方法应用于中国黄海沿岸实际海水样品中痕量硒、砷、汞的定量分析,分析结果与电感耦合等离子体质谱法一致,用标准加入法测得其加标回收率在94.9%～105.3%之间。氢化物发生-液体阴极辉光放电发射光谱能够实现快速、准确地对海水中痕量硒、砷、汞的高灵敏在线定量检测。

关键词：氢化物发生液体阴极辉光放电发射光谱硒砷汞

Different Impacts of Aerosols on Cloud Development over Land and Ocean Regions in East China

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Advances in Atmospheric Sciences 2025年第4期42卷 731-743页

作者： Xin zhao Chuanfeng zhao Yulei CHI Jie YANG yue SUN Yikun YANG Hao FAN Faculty of Geographical Science Beijing Normal UniversityBeijing 100875China Laboratory for Climate and Ocean–Atmosphere Studies Department of Atmosphere and Oceanic SciencesSchool of PhysicsPeking UniversityBeijing 100871China School of Systems Science Beijing Normal UniversityBeijing 100875China

The impact of aerosols on clouds,which remains one of the largest aspects of uncertainty in current weather forecasting and climate change research,can be influenced by various factors,such as the underlying surface type,cloud type,cloud phase,and aerosol *** explore the impact of different underlying surfaces on the effect of aerosols on cloud development,this study focused on the Yangtze River Delta(YRD)and its offshore regions(YRD sea)for a comparative analysis based on multi-source satellite data,while also considering the variations in cloud type and cloud *** results show lower cloud-top height and depth of single-layer clouds over the ocean than land,and higher liquid cloud in spring over the *** are found to enhance the cumulus cloud depth through microphysical effects,which is particularly evident over the *** are also found to decrease the cloud droplet effective radius in the ocean region and during the mature stage of cloud development in the land region,while opposite results are found during the early stage of cloud development in the land *** quantitative results indicate that the indirect effect is positive(0.05)in the land region at relatively high cloud water path,which is smaller than that in the ocean region(0.11).The findings deepen our understanding of the influence aerosols on cloud development and the mechanisms involved,which could then be applied to improve the ability to simulate cloud-associated weather processes.

关键词： cloud depth cloud effective radius aerosol land ocean