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Global practical stabilization of the double integrator system with an imperfect sensor and subject to a bounded disturbance

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Control Theory and Technology 2024年第3期22卷 468-478页

作者： Zhiyuan zhu Yuanlong Li Zongli Lin Department of Automation Shanghai Jiao Tong Universityand Key Laboratory of System Control and Information Processing of Ministry of EducationShanghai 200240China Charles L.Brown Department of Electrical and Computer Engineering University of VirginiaP.0.Box 400743CharlottesvilleVA 22904-4743USA

This paper is concerned with global practical stabilization of the double integrator system with an imperfect sensor and subject to an additive bounded output *** imperfect sensor nonlinearity possesses the nonlinear characteristics of saturation and dead *** of the presence of output dead zone and the additive disturbance,the states cannot be expected to driven into an arbitrarily small neighborhood of the *** solve the global practical stabilization problem,we proposes a low gain-based linear dynamic output feedback law,under which the first state enters and remains in a bounded set whose size is depended on the bound of disturbance and the range of dead zone and the second state enters and remains in a pre-specified arbitrarily small set,both in finite *** results illustrate the effectiveness of our proposed control method.

关键词： Output saturation Disturbance rejection Output dead zone Low gain feedback-Linear output feedback Practical stabilization

Spatio-temporal Evaluation of Multi-scale Cultivated Land System Resilience in Black Soil Region from 2000 to 2019:A Case Study of Liaoning Province,Northeast China

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Chinese Geographical Science 2024年第1期34卷 168-180页

作者： WANG Yue JIANG Yuting zhu Guoxu School of Management Shenyang Normal UniversityShenyang110034China Northeast Institute of Geography and Agroecology Chinese Academy of SciencesChangchun130012China

It is of great significance to systematically analyze the cultivated land system resilience(CLSR) for the black soil protection and national food *** CLSR is impacted by planting structure adjustment and cultivated land quality decline,posing major hidden dangers to food *** is urgent to evaluate the CLSR at multiple spatio-temporal *** study took Liaoning Province in the black soil region of Northeast China as an *** on the resilience theory,this study constructed the CLSR evaluation system from the input-feedback perspective at the provincial-scale and the city-scale,and used the rank-sum ratio comprehensive evaluation method(RSR) to analyze the key influencing factors of CLSR in Liaoning Province and its 14 cities from 2000 to *** results showed that:1) the time series changes of CLSR at the provincial-scale and the city-scale in Liaoning Province were similar,both showing an increasing trend.2) The CLSR in Liaoning Province presented a spatial pattern of ‘high in the west and low in the east’ at the city-scale.3) There were seven and six main influencing factors of CLSR at the provincial-scale and the city-scale,*** addition to the net income per capita of rural households,other influencing factors of CLSR were different at the provincial-scale and the *** feedback factors were dominant at the provincial-scale,and the input factors and feedback factors were dominant at the *** results could provide a reference for the utilization of black soil and draw on the experience of regional agricultural planning and adjustment.

关键词： cultivated land system resilience(CLSR) rank-sum ratio comprehensive evaluation(RSR) multi-scales influencing factors black soil region Liaoning Province,China

Distributed order estimation for continuous-time stochastic systems

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Control Theory and Technology 2024年第3期22卷 406-418页

作者： Xinghua zhu Zhixin Liu Xiaoming Hu Key Laboratory of Systems and Control Academy of Mathematics and Systems ScienceBeijing 100190China School of Mathematical Sciences University of Chinese Academy of SciencesBeijing 100190China Department of Mathematics KTH Royal Institute of TechnologyStockholm 10044Sweden

In this paper,we investigate the distributed estimation problem of continuous-time stochastic dynamic systems over sensor networks when both the system order and parameters are *** propose a local information criterion(LIC)based on the L_(0)penalty *** minimizing LIC at the diffusion time instant and utilizing the continuous-time diffusion least squares algorithm,we obtain a distributed estimation algorithm to simultaneously estimate the unknown order and the parameters of the *** dealing with the effect of the system noises and the coupling relationship between estimation of system orders and parameters,we establish the almost sure convergence results of the proposed distributed estimation ***,we give a simulation example to verify the effectiveness of the distributed algorithm in estimating the system order and parameters.

关键词： Stochastic differential equations Sensor networks Distributed order estimation Cooperative excitation condition.Convergence

For LEO Satellite Networks: Intelligent Interference Sensing and Signal Reconstruction Based on Blind Separation Technology

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China Communications 2024年第2期21卷 85-95页

作者： Chengjie Li Lidong zhu Zhen Zhang The Key Laboratory for Computer Systems of State Ethnic Affairs Commission School of Computer Science and Technology(Southwest Minzu University)Chengdu 610000China National Key Laboratory of Science and Technology on Communications(University of Electronic Science and Technology of China) Chengdu 610000China College of Computer Science(Sichuan University) Chengdu 610000China

In LEO satellite communication networks,the number of satellites has increased sharply, the relative velocity of satellites is very fast, then electronic signal aliasing occurs from time to time. Those aliasing signals make the receiving ability of the signal receiver worse, the signal processing ability weaker,and the anti-interference ability of the communication system lower. Aiming at the above problems, to save communication resources and improve communication efficiency, and considering the irregularity of interference signals, the underdetermined blind separation technology can effectively deal with the problem of interference sensing and signal reconstruction in this scenario. In order to improve the stability of source signal separation and the security of information transmission, a greedy optimization algorithm can be executed. At the same time, to improve network information transmission efficiency and prevent algorithms from getting trapped in local optima, delete low-energy points during each iteration process. Ultimately, simulation experiments validate that the algorithm presented in this paper enhances both the transmission efficiency of the network transmission system and the security of the communication system, achieving the process of interference sensing and signal reconstruction in the LEO satellite communication system.

关键词： blind source separation greedy optimization algorithm interference sensing LEO satellite communication networks signal reconstruction

带-NH2的嘧啶环对钌配合物与DNA相互作用的瞬态发光特性的影响

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光学学报 2008年第6期28卷 1155-1160页

作者：朱伟玲刘学文王惠于会娟巢晖郑康成计亮年茂名学院物理系广东茂名525000 湖南文理学院化学化工系湖南常德415000 中山大学光电材料与技术国家重点实验室广东广州510275 中山大学化学与化学工程学院广东广州510275

采用时间分辨的发光光谱技术,分别测量了两种新合成的钌配合物[Ru(bpy)2(dpbpd(NH2)2)]2+和[Ru(phen)2(dpbpd(NH2)2)]2+与小牛胸腺脱氧核糖核酸(ctDNA)相互作用时的瞬态发光动力学过程,并与以往对[Ru(phen)2dppz]2+等的研究结果进行对比... 详细信息

采用时间分辨的发光光谱技术,分别测量了两种新合成的钌配合物[Ru(bpy)2(dpbpd(NH2)2)]2+和[Ru(phen)2(dpbpd(NH2)2)]2+与小牛胸腺脱氧核糖核酸(ctDNA)相互作用时的瞬态发光动力学过程,并与以往对[Ru(phen)2dppz]2+等的研究结果进行对比,从而研究带-NH2的嘧啶环对配合物与DNA作用动力学过程的影响。结果表明:这两种含有带-NH2的嘧啶环的钌配合物与DNA相互作用时的发光按双指数规律衰减,发光寿命为几十纳秒,比dppz类钌配合物与DNA作用时的发光衰变寿命(几百纳秒)小一个数量级。归因于嘧啶环上的N和-NH2可能与水分子、DNA的碱基对或磷酸骨架形成氢键,从而加快激发态的无辐射弛豫,削弱发射光强,缩短发光寿命。该结论为进一步研究配合物分子与DNA的相互作用的机理提供了一定的依据。

关键词：超快激光与光电子学瞬态发光时间分辨光谱术钌配合物 DNA

Vector Radiative Transfer in a Vertically Inhomogeneous Scattering and Emitting ***Ⅰ:A New Discrete Ordinate Method

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Journal of Meteorological Research 2024年第2期38卷 209-224页

作者： Ziqiang zhu Fuzhong WENG Yang HAN Chinese Academy of Meteorological Sciences China Meteorological AdministrationBeijing 100081 University of Chinese Academy of Sciences Beijing 100049 CMA Earth System Modeling and Prediction Centre China Meteorological Administration(CMA)Beijing 100081 State Key Laboratory of Severe Weather Chinese Academy of Meteorological SciencesChina Meteorological AdministrationBeijing 100081

The original vector discrete ordinate radiative transfer(VDISORT)model takes into account Stokes radiance vector but derives its solution assuming azimuthal symmetric surface reflective matrix and atmospheric scattering phase matrix,such as the phase matrix derived from spherical particles or randomly oriented non-spherical *** this study,a new VDISORT is developed for general atmospheric scattering and boundary *** vector is decomposed into both sinusoidal and cosinusoidal harmonic modes,and the radiance at arbitrary viewing geometry is solved directly by adding two zero-weighted points in the Gaussian quadrature *** complex eigenvalues in homogeneous solutions are also taken into full *** accuracy of VDISORT model is comprehensively validated by four cases:Rayleigh scattering case,the spherical particle scattering case with the Legendre expansion coefficients of 0th-13th orders of the phase matrix(hereinafter L13),L13 with a polarized source,and the randomoriented oblate particle scattering case with the Legendre expansion coefficients of 0th-11th orders of the phase matrix(hereinafter L11).In all cases,the simulated radiances agree well with the benchmarks,with absolute biases less than 0.0065,0.0006,and 0.0008 for Rayleigh,unpolarized L13,and L11,*** a polarized bidirectional reflection distribution function(pBRDF)matrix is used as the lower boundary condition,VDISORT is now able to handle fully coupled atmospheric and surface polarimetric radiative transfer processes.

关键词： radiative transfer discrete ordinate polarization Stokes vector vector discrete ordinate radiative transfer(VDISORT)

Rationally construction of atomic-precise interfacial charge transfer channel and strong build-in electric field in nanocluster-based Zscheme heterojunctions with enhanced photocatalytic hydrogen production

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Nano Research 2024年第6期17卷 5002-5010页

作者： Qingtao zhu Honglei Shen Chao Han Liu Huang Yanting Zhou Yuanxin Du Xi Kang Manzhou zhu Department of Materials Science and Engineering Centre for Atomic Engineering of Advanced MaterialsKey Laboratory of Structure and Functional Regulation of Hybrid Materials of Ministry of EducationKey Laboratory of Functional Inorganic Material Chemistry of Anhui ProvinceAnhui UniversityHefei 230601China

The lack of effective charge transfer driving force and channel limits the electron directional migration in nanoclusters(NC)-based heterostructures,resulting in poor photocatalytic ***,a Z-scheme NC-based heterojunction(Pt1Ag28-BTT/CoP,BTT=1,3,5-benzenetrithiol)with strong internal electric field is constructed via interfacial Co-S bond,which exhibits an absolutely superiority in photocatalytic performance with 24.89 mmol·h^(−1)·g−1 H_(2)production rate,25.77%apparent quantum yield at 420 nm,and~100%activity retention in stability,compared with Pt1Ag28-BDT/CoP(BDT=1,3-benzenedithiol),Ag29-BDT/CoP,and *** enhanced catalytic performance is contributed by the dual modulation strategy of inner core and outer shell of NC,wherein,the center Pt single atom doping regulates the band structure of NC to match well with CoP,builds internal electric field,and then drives photogenerated electrons steering;the accurate surface S modification promotes the formation of Co-S atomic-precise interface channel for further high-efficient Z-scheme charge directional *** work opens a new avenue for designing NC-based heterojunction with matchable band structure and valid interfacial charge transfer.

关键词： atomically precise metal nanocluster Z-scheme heterojunction interfacial charge transfer build-in electric field photocatalytic hydrogen production

CMAGAN:classifier-aided minority augmentation generative adversarial networks for industrial imbalanced data and its application to fault prediction

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Advances in Manufacturing 2024年第3期12卷 603-618页

作者： Wen-Jie Wang Zhao Liu Ping zhu School of Mechanical Engineering Shanghai Jiao Tong UniversityShanghai200240People’s Republic of China National Engineering Research Center of Automotive Power and Intelligent Control Shanghai Jiao Tong UniversityShanghai200240People’s Republic of China School of Design Shanghai Jiao Tong UniversityShanghai200240People’s Republic of China

Class imbalance is a common characteristic of industrial data that adversely affects industrial data mining because it leads to the biased training of machine learning *** address this issue,the augmentation of samples in minority classes based on generative adversarial networks(GANs)has been demonstrated as an effective *** study proposes a novel GAN-based minority class augmentation approach named classifier-aided minority augmentation generative adversarial network(CMAGAN).In the CMAGAN framework,an outlier elimination strategy is first applied to each class to minimize the negative impacts of ***,a newly designed boundary-strengthening learning GAN(BSLGAN)is employed to generate additional samples for minority *** incorporating a supplementary classifier and innovative training mechanisms,the BSLGAN focuses on learning the distribution of samples near classification ***,it can fully capture the characteristics of the target class and generate highly realistic samples with clear ***,the new samples are filtered based on the Mahalanobis distance to ensure that they are within the desired *** evaluate the effectiveness of the proposed approach,CMAGAN was used to solve the class imbalance problem in eight real-world fault-prediction *** performance of CMAGAN was compared with that of seven other algorithms,including state-of-the-art GAN-based methods,and the results indicated that CMAGAN could provide higher-quality augmented results.

关键词： Class imbalance Minority class augmentation Generative adversarial network(GAN) Boundary strengthening learning(BSL) Fault prediction

Understanding microstructure-property relationships of HPDC Al-Si alloy based on machine learning and crystal plasticity simulation

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Advances in Manufacturing 2024年第3期12卷 497-511页

作者： Qiang-Qiang Zhai Zhao Liu Ping zhu State Key Laboratory of Mechanical System and Vibration Shanghai Jiao Tong UniversityShanghai200240People’s Republic of China National Engineering Research Center of Automotive Power and Intelligent Control Shanghai Jiao Tong UniversityShanghai200240People’s Republic of China School of Design Shanghai Jiao Tong UniversityShanghai200240People’s Republic of China

Al-Si alloys manufactured via high-pressure die casting(HPDC)are suitable for a wide range of ***,the heterogeneous microstructure and unpredictable pore distribution of Al-Si high-pressure die castings result in significant variations in the mechanical properties,thus leading to a complicated microstructure-property relationship that is difficult to ***,a computational framework incorporating machine learning and crystal plasticity method is *** framework aims to provide a systematic and comprehensive understanding of this relationship and enable the rapid prediction of macroscopic mechanical properties based on the ***,we select eight variables that can effectively characterize the microstructural features and then obtain their statistical ***,based on 160 samples obtained via the Latin hypercube sampling method,representative volume elements are constructed,and the crystal plasticity fast Fourier transformation method is executed to obtain the macroscopic mechanical ***,the yield strength,elastic modulus,strength coefficient,and strain-hardening exponent are used to characterize the stress-strain curve,and Gaussian process regression models and microstructural variables are ***,sensitivity and univariate analyses based on these machine-learning models are performed to obtain insights into the microstructure-property relationships of the HPDC Al-Si *** results show that the Gaussian process regression models exhibit high accuracy(R2 greater than 0.84),thus confirming the viability of the proposed *** results of sensitivity analysis indicate that the pore size exerts the most significant effect on the mechanical ***,the proposed framework can not only be transferred to other alloys but also be employed for material design.

关键词： High-pressure die casting(HPDC) Machine learning Crystal plasticity Aluminum alloys