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State estimate for stochastic systems with dual unknown interference inputs

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Chinese Journal of Aeronautics 2020年第9期33卷 2395-2407页

作者： xiaoxue feng Shuhui LI feng PAN School of Automation Beijing Institute of TechnologyBeijing 100081China Kunming-BIT Industry Technology Research Institute INC Kunming 650106China

Stochastic system state estimation subject to the unknown interference input widely exists in many fields,such as the control,communication,signal processing,and fault ***,the research results are mostly limited to the stochastic system in which only the dynamic state model or the measurement model concerns the individual unknown interference input,and the state model and the measurement model are both with the same unknown interference *** estimate of the stochastic systems where the state model and the measurement model contain dual Unknown Interference inputs(dual-UI)with different physical meanings and mathematical definitions is concerned ***,the decoupling condition with the Unknown Interference input in the State model(S-UI)is shown,which introduces the decoupled system with the adjacent Measurement concerned Unknown Interference inputs(M-UI)appearing in the state model and the measurement ***,through defining the Differential term of the adjacent M-UI(M-UID),the equivalent system with only M-UID in the state model is ***,considering the design freedom of the equivalent system,the decoupling filter in the minimum mean square error sense and the adaptive minimum upper filter with different applicable conditions are represented to obtain the optimal and sub-optimal state estimate,*** simulation cases verify the effectiveness and superiority compared with the traditional methods.

关键词： Adaptive filter Decoupling filter State estimate Stochastic system Unknown interference input

Joint parameter and state estimation for stochastic uncertain system with multivariate skew t noises

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Chinese Journal of Aeronautics 2022年第5期35卷 69-86页

作者： Shuhui LI Zhihong DENG xiaoxue feng Ruxuan HE feng PAN School of Automation Beijing Institute of TechnologyBeijing 100081China Kunming-BIT Industry Technology Research Institute INC Kunming 650106China

Due to the pulse interference, measurement outliers and artificial modeling errors, the multivariate skew t noise widely exists in the real environment. However, to date, little attention has been paid to the state estimation for systems in which the process noise and the measurement noise are both modeled as the heavy-tailed and skew non-Gaussian noise. In this paper, the multivariate skew t distribution is utilized to model the heavy-tailed and skew non-Gaussian noise. Then a probabilistic graphical form of the multivariate skew t distribution is given and proved. Based on the probabilistic graphical form, a hierarchical Gaussian state space model for stochastic uncertain systems is proposed, which transforms the estimation problem for systems with the heavy-tailed and skew non-Gaussian noises into the one with a hierarchical Gaussian state space model. Next, given the designed Gaussian state space model, the robust Bayesian filter and smoother based on the variational Bayesian inference are proposed to approximately estimate the system state and the unknown noise parameters. Furthermore, the complexity analysis together with the controllability and observability for stochastic uncertain systems with multivariate skew t noises is given. Finally,the simulation results of the target tracking scenario verify the validity of the proposed algorithms.

关键词： Estimation methods Non-Gaussian noise Target tracking Uncertain systems Variational principles

建立依帕司他原料粒度检测方法的质量控制措施

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化工管理 2024年第8期 66-68页

作者：冯小雪薛雯蔚尤锐扬子江药业集团南京海陵药业有限公司江苏南京210049

采用依帕司他原料粒度和粒度分布测定方法,探索并进行方法学研究,对折射率、分散压力、进样速率等参数进行确定,并对最终建立的粒度和粒度分布测定方法进行重复性试验、中间精密度试验、耐用性试验等方法学考察,结果显示:折射率、分散... 详细信息

采用依帕司他原料粒度和粒度分布测定方法,探索并进行方法学研究,对折射率、分散压力、进样速率等参数进行确定,并对最终建立的粒度和粒度分布测定方法进行重复性试验、中间精密度试验、耐用性试验等方法学考察,结果显示:折射率、分散压力、进样速率等参数均符合标准规定,方法良好。建立的激光粒度法(干法)适用于依帕司他原料粒度及粒度分布测定,可用于相关医药制剂的研发及生产的质量控制。

关键词：粒度分布光散射法依帕司他医药化工

Fault Detection of Networked Control System subject to Random Packet Dropout and Multi-Rate Sample Data

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Fault Detection of Networked Control System subject to Rando...

第36届中国控制会议

作者： feng xiaoxue PAN feng Li Shuhui School of Automation Beijing Institute of Technology

ISBN: (纸本)9781538629185

In this paper,the problem of fault detection is addressed for networked control system（NCS） subject to both random packet dropout and multi-rate sampled data,which is usually *** the networked control system suffers heavy resources competition and network congestion under the limited bandwidth,resulting in multi-rate sampling and data packet *** based residual generation and evaluation approach is ***,by lifting the multi-rate multi-sensor model to a single-rate one,a residual generator with causality constraint is ***,the parameters of the residual generator are achieved by optimizing a performance index,which is robust to the unknown disturbances and packet dropout without loss of the sensitivity to the ***,an appropriate threshold of residual evaluation is calculated by making full use of the stochastic properties of the *** results are given to illustrate the effectiveness of the proposed method.

关键词： Fault detection Residual generation Residual evaluation Packet dropout Multi-rate sensors

来源： cnki会议评论

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温度对换流变压器瞬态电场的影响分析

电器与能效管理技术 2024年第6期 17-24页

作者：李茜高有华冯小雪张铭洋沈阳工业大学辽宁沈阳110870 国家电网沈阳供电公司辽宁沈阳110023

基于传统变压器的绝缘设计并未考虑油纸绝缘的非线性特性,采用有限元法将电磁场、温度场等多物理场进行耦合仿真计算,重点研究油纸复合绝缘的电导率随温度非线性变化时,换流变压器阀侧绕组端部暂态电场分布的规律和特征,以及油、纸板电... 详细信息

基于传统变压器的绝缘设计并未考虑油纸绝缘的非线性特性,采用有限元法将电磁场、温度场等多物理场进行耦合仿真计算,重点研究油纸复合绝缘的电导率随温度非线性变化时,换流变压器阀侧绕组端部暂态电场分布的规律和特征,以及油、纸板电导率比值对阀侧电场的影响。结果表明:考虑温度电导率非线性特性时,换流变压器阀侧端部的电场分布更加集中,畸变现象更明显,且随着电导率比值的增大,阀侧绕组端部的等位线分布越来越密集,高场强值集中在阀侧绕组端部绝缘纸板之间的油隙中。所提研究为变压器绝缘设计提供技术支持。

关键词：换流变压器极性反转非线性暂态电场油纸绝缘温度影响

维普期刊数据库博看期刊

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引入控制量变化率约束的双层协同轨迹规划器

宇航学报 2024年第1期45卷 101-109页

作者：温岳冯肖雪谢天龚柏春吴云华北京理工大学自动化学院北京100081 南京航空航天大学航天学院南京210016

针对亚音速飞行器编队飞行轨迹规划约束复杂、求解困难的问题,提出了一种引入控制量变化率约束的双层亚音速飞行器协同轨迹规划器。首先,引入控制量变化率约束以保证轨迹可行性,为了避免增加新的状态方程而增加计算量,采用拉格朗日插值... 详细信息

针对亚音速飞行器编队飞行轨迹规划约束复杂、求解困难的问题,提出了一种引入控制量变化率约束的双层亚音速飞行器协同轨迹规划器。首先,引入控制量变化率约束以保证轨迹可行性,为了避免增加新的状态方程而增加计算量,采用拉格朗日插值多项式计算控制变量变化率,将其作为求解最优控制问题伪谱法的约束条件。然后,使用顶层单飞行器规划器在不考虑多飞行器协同约束的条件下使用较少配点的伪谱法快速求解每个飞行器的粗略轨迹结果,求解结果使用拉格朗日插值作为底层多飞行器规划器的初值。底层多飞行器规划器使用更多的配点以确保求解的精度,在考虑多飞行器协同约束条件下进行伪谱法求解,以解决伪谱法初值敏感问题并提高优化效率。最后仿真结果表明了所提方法的有效性,与引入虚拟控制量而增加状态方程方法相比,此方法计算量更小,求解效率更优,满足协同轨迹规划的要求。

关键词：编队飞行轨迹规划变化率约束双层规划器

Policy Network-Based Dual-Agent Deep Reinforcement Learning for Multi-Resource Task Offloading in Multi-Access Edge Cloud Networks

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China Communications 2024年第4期21卷 53-73页

作者： feng Chuan Zhang Xu Han Pengchao Ma Tianchun Gong xiaoxue School of Communications and Information Engineering Chongqing University of Posts and TelecommunicationsChongqing 400065China Institute of Intelligent Communication and Network Security Chongqing University of Posts and TelecommunicationsChongqing 400065China Key Laboratory of Big Data Intelligent Computing Chongqing University of Posts and TelecommunicationsChongqing 400065China School of Information Engineering Guangdong University of TechnologyGuangzhou 510006China

The Multi-access Edge Cloud(MEC) networks extend cloud computing services and capabilities to the edge of the networks. By bringing computation and storage capabilities closer to end-users and connected devices, MEC networks can support a wide range of applications. MEC networks can also leverage various types of resources, including computation resources, network resources, radio resources,and location-based resources, to provide multidimensional resources for intelligent applications in 5/***, tasks generated by users often consist of multiple subtasks that require different types of resources. It is a challenging problem to offload multiresource task requests to the edge cloud aiming at maximizing benefits due to the heterogeneity of resources provided by devices. To address this issue,we mathematically model the task requests with multiple subtasks. Then, the problem of task offloading of multi-resource task requests is proved to be NP-hard. Furthermore, we propose a novel Dual-Agent Deep Reinforcement Learning algorithm with Node First and Link features(NF_L_DA_DRL) based on the policy network, to optimize the benefits generated by offloading multi-resource task requests in MEC networks. Finally, simulation results show that the proposed algorithm can effectively improve the benefit of task offloading with higher resource utilization compared with baseline algorithms.

关键词： benefit maximization deep reinforcement learning multi-access edge cloud task offloading

Integrating Bimetallic Nanoparticles with Covalent Organic Frameworks as Multifunctional Nanozyme for Colorimetric Detection of Hydrogen Peroxide and Glutathione

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Journal of Analysis and Testing 2024年第03期8卷 278-287页

作者： Yuying Yuan xiaoxue Xi Ting Bao Pingguan Bian feng Pei Xiuhua Zhang Shengfu Wang Wei Wen Collaborative Innovation Center for Advanced Organic Chemical Materials Co-constructed by the Province and Ministry of Education Key Laboratory for the Synthesis and Application of Organic Functional MoleculesCollege of Chemistry and Chemical EngineeringHubei University Hubei Yihua Chemical Co. Ltd

The controllable growth of metal nanoparticles on nanomaterials is becoming an effective strategy for developing nanocomposites with designated performance. Herein, a simple and mild strategy for the in situ growth of Pt–Pd bimetallic nanoparticles on covalent organic frameworks（COFs） to regulate the nanozyme activity was designed for colorimetric detection of hydrogen peroxide（H2O2） and glutathione（GSH）. The COFs not only offer sufficient loading sites for the uniform dispersion of Pt–Pd bimetallic nanoparticles, but also increase the adsorption of substrate to promote the catalytic reaction. With the bimetallic synergistic effect of Pt–Pd nanoparticles, the prepared multifunctional nanozyme（Pt–Pd/COFs nanozyme） simultaneously exhibited superior peroxidase（POD）-like activity and oxidase（OXD）-like activity. Using the multifunctional nanozyme, a colorimetric sensing system was constructed for sensitive detection of H2O2and GSH, with the wide linear ranges of 5–1000 μmol/L and 1–40 μmol/L, and the detection limits were 1.14 μmol/L and 0.43 μmol/L, respectively. It was successfully used for the detection of real samples in environmental water and serum, providing a simple method for disease diagnosis and environmental monitoring.

关键词： Bimetallic synergistic effect H2O2 and GSH detection Oxidase-like activity Peroxidase-like activity Pt–Pd/COFs nanozyme

Joint State and Parameter Estimation for Stationary ARMA Model with Unknown Noise Model

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Joint State and Parameter Estimation for Stationary ARMA Mod...