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Journal of Systems Science & Complexity 2023年第2期36卷 500-523页

作者： kang yu YANG yuxiao CHEN Cai LüWenjun ZHAO yunbo Department of Automation University of Science and Technology of ChinaHefei 230027China Institute of Advanced Technology University of Science and Technology of ChinaHefei 230027China State Key Laboratory of Fire Science University of Science and Technology of ChinaHefei 230027China

A robust nonsingular fixed time terminal sliding mode control scheme with a time delay disturbance observer is proposed for atmospheric pollution detection lidar scanning mechanism(APDL-SM)*** from the conventional terminal sliding mode control methods,the authors design a novel fixed-time terminal sliding surface,the convergence time of sliding mode phase of which has a constant upper bound that is designable by adjusting only one ***,in order to overcome the problem of unknown upper bound of lumped uncertainty including model uncertainty,friction effect and external disturbances from the port environment,the authors propose a time delay disturbance observer to provide an estimation for the system lumped *** using the Lyapunov synthesis,the explicit analysis of the convergence time upper bound are ***,simulation studies are conducted on the APDL-SM system to show the fast convergence rate and strong robustness of the proposed control scheme.

关键词： Atmospheric pollution detection lidar fixed time terminal sliding mode time delay disturbance observer tracking control

Model-Based Network Scheduling and Control for Systems over the IEEE 802.15.4 Network

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Journal of Systems Science & Complexity 2021年第1期34卷 281-297页

作者： ZHAO yunbo XU Deheng HE Jiangtao XI Xugang kang yu College of Information Engineering Zhejiang University of TechnologyHangzhou 310023China School of Automation Hangzhou Dianzi UniversityHangzhou 310018China Department of Automation University of Science and Technology of ChinaHefei 230027China

The scheduling and control of a class of wireless networked control system is investigated,whose control loop is closed via a shared IEEE 802.15.4 wireless network. By using a gain scheduler within the packet-based control framework and fitting the delay-dependent gains into a time-delay system model, a less conservative self-triggered approach is proposed to determine the sampling update,which consequently enables the design of two network scheduling algorithms to reduce the communication usage. Numerical and TrueT ime based examples illustrate the effectiveness of the proposed approach in the sense that it reduces greatly the communication usage while maintaining satisfactory control performance.

关键词： IEEE 802.15.4 packet-based control scheduling wireless networked control system

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神威超级计算机运行时故障定位方法

计算机研究与发展 2024年第1期61卷 86-97页

作者：高剑刚郑岩于康彭达佳李宏亮刘勇何王全陈德训王飞国家并行计算机工程技术研究中心北京100190 江南计算技术研究所江苏无锡214083

随着高性能计算机的性能不断提升、系统规模不断提高,系统和应用的错误率也不可避免地持续增多.快速发现和定位系统及应用级的错误、为用户提供高质量服务,成为了超级计算机系统设计开发过程中急需考虑的问题.超级计算机系统中硬件故障... 详细信息

随着高性能计算机的性能不断提升、系统规模不断提高,系统和应用的错误率也不可避免地持续增多.快速发现和定位系统及应用级的错误、为用户提供高质量服务,成为了超级计算机系统设计开发过程中急需考虑的问题.超级计算机系统中硬件故障与异常、软件程序的错误等都会导致用户大规模并行应用的错误、挂死与退出.如何快速准确定位错误现场,让管理员或用户以此为基础查看异常发生的故障进行高精度、高效率的诊断,是维护高性能计算系统可靠性的重要基础.高性能计算机传统的故障定位主要通过硬件异常跟踪、系统日志分析和程序主动探测等方法,缺乏对无日志信息、无明显故障现象的程序挂死问题的定位手段,并且技术的扩展性也面临挑战.针对“新一代神威超级计算机”体系结构和SW26010-Pro众核处理器特点,提出一种运行时故障定位方法,包括基于消息传递的故障关联分析、基于全局聚合信息的在线综合分析诊断、面向申威众核处理器的异常线程过滤方法等关键技术,阐述了如何有效检测、收集、处理大量系统资源和并行进程的异常信息问题,为应对未来超大规模高性能计算中故障高效定位难题提供有效支撑.

关键词： E级计算机可靠性错误定位运行时众核处理器

Trust-Region Based Stochastic Variational Inference for Distributed and Asynchronous Networks

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Journal of Systems Science & Complexity 2022年第6期35卷 2062-2076页

作者： FU Weiming QIN Jiahu LING Qing kang yu YE Baijia Department of Automation University of Science and Technology of ChinaHefei 230027China Institute of Artificial Intelligence Hefei Comprehensive National Science CenterHefei 230088China School of Computer Science and Engineering and Guangdong Province Key Laboratory of Computational ScienceSun Yat-Sen UniversityGuangzhou 510006China Institute of Advanced Technology University of Science and Technology of ChinaHefei 230027China

Stochastic variational inference is an efficient Bayesian inference technology for massive datasets,which approximates posteriors by using noisy gradient *** stochastic variational inference can only be performed in a centralized manner,which limits its applications in a wide range of situations where data is possessed by multiple ***,this paper develops a novel trust-region based stochastic variational inference algorithm for a general class of conjugate-exponential models over distributed and asynchronous networks,where the global parameters are diffused over the network by using the Metropolis rule and the local parameters are updated by using the trust-region ***,a simple rule is introduced to balance the transmission frequencies between neighboring nodes such that the proposed distributed algorithm can be performed in an asynchronous *** utility of the proposed algorithm is tested by fitting the Bernoulli model and the Gaussian model to different datasets on a synthetic network,and experimental results demonstrate its effectiveness and advantages over existing works.

关键词： Asynchronous networks Bayesian inference distributed algorithm stochastic variational inference trust-region method

肌骨超声监测火针治疗膝骨关节炎疗效的临床研究

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新疆中医药 2024年第3期42卷 9-11页

作者：夏江燕蔡玉新亢玉新乌鲁木齐市中医医院新疆乌鲁木齐830000 乌鲁木齐市中医医院医学影像科新疆乌鲁木齐830000

目的探讨肌骨超声监测火针治疗膝骨关节炎的临床效果。方法将2022年4月~2023年12月乌鲁木齐市中医医院针灸科收治的130例膝骨关节炎患者进行研究。分组方法选择随机数字表法,分为对照组、观察组,各65例。观察组接受火针针刺治疗,对照... 详细信息

目的探讨肌骨超声监测火针治疗膝骨关节炎的临床效果。方法将2022年4月~2023年12月乌鲁木齐市中医医院针灸科收治的130例膝骨关节炎患者进行研究。分组方法选择随机数字表法,分为对照组、观察组,各65例。观察组接受火针针刺治疗,对照组接受普通针刺治疗,同时进行肌骨超声监测。比较两组患者的临床疗效,对比分析治疗前、后膝关节积液深度的变化,滑膜厚度及滑膜血流信号的变化情况。结果观察组的治疗总有效率为96.92%,对照组治疗总有效率为87.69%,观察组高于对照组(P<0.05);观察组治疗后膝关节积液(10.22±2.06)mm较治疗前(4.12±1.08)mm降低。对照组治疗后膝关节积液(10.18±1.85)mm较治疗前(6.03±1.34)mm降低。观察组较对照组显著降低(P<0.05)。治疗后滑膜厚度观察组较对照统计学结果有显著差异(P<0.05);治疗后检测出观察组滑膜血流信号分级较观察组减低,统计学结果有显著差异(P<0.05)。结论火针治疗膝骨关节炎效果优于普通针刺,采用肌骨超声监测能够为膝骨关节炎的康复治疗提供依据。

关键词：膝骨关节炎肌骨超声火针膝关节积液深度滑膜厚度血流信号

Extension Problems Related to the Higher Order Fractional Laplacian

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Acta Mathematica Sinica,English Series 2018年第4期34卷 655-661页

作者： yu kang CHEN Zhen LEI Chang Hua WEI School of Mathematical Sciences Fudan University Shanghai 200433 P. R. China School of Mathematical Sciences and Shanghai Center for Mathematical Sciences Fudan University Shanghai 200433 P. R. China Department of Mathematics Zhejiang Sci-Tech University Hangzhou 310018 P. R. China

Caffarelli and Silvestre [Comm. Part. Diff. Eqs., 32, 1245-1260 （2007）] characterized the fractional Laplacian （-△）s as an operator maps Dirichlet boundary condition to Neumann condition via the harmonic extension problem to the upper half space for 0 〈 s 〈 1. In this paper, we extend this result to all s 〉 0. We also give a new proof to the dissipative a priori estimate of quasi-geostrophic equations in the framework of Lp norm using the Caffarelli-Silvestre＇s extension technique.

关键词： Fractional Laplacian quasi-geostrophic equations energy equality

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多特征融合的近红外脑血氧随机森林分类识别

光谱学与光谱分析 2024年第10期44卷 2858-2864页

作者：谢惜如罗海军李国楠范鑫燕王康宇李忠洪王洁重庆师范大学物理与电子工程学院光电功能材料重庆市重点实验室重庆401331 重庆师范大学重庆国家应用数学中心重庆401331

为了解决脑机接口中功能性近红外脑功能成像信号的数据分类精度低、模型稳定性差的问题,提出研究前额叶脑区在刺激期间脑血氧浓度的变化,并对前额叶脑区实验数据进行任务与休息的状态二分类识别研究,将提取的单特征和多特征融合分别作... 详细信息

为了解决脑机接口中功能性近红外脑功能成像信号的数据分类精度低、模型稳定性差的问题,提出研究前额叶脑区在刺激期间脑血氧浓度的变化,并对前额叶脑区实验数据进行任务与休息的状态二分类识别研究,将提取的单特征和多特征融合分别作为模型的输入,通过模型分类结果验证多特征融合可以在一定程度上提高分类精度的猜想。首先针对前额叶脑区设计实验范式:词语流畅性认知实验。采集数据的设备是中国丹阳慧创设备NirSmart,采样率为11 Hz,空间分辨率为3 cm。设备使用雪崩二极管和超微光探测技术,灵敏度可达0.1 pW。之后使用Homer2工具箱对采集数据进行预处理,以及使用MATLAB进行特征的提取、随机森林模型的构建,使用特征重要性和误差曲线两个指标来评估模型的性能,最后将随机森林模型运行20次的平均值作为最终的分类结果。实验结果表明,多特征融合与单特征相较提高了最终的分类结果。其中三特征融合状态二分类结果最佳为93.84%,比单特征均值、斜率、峰峰值分别提高了2.32%、4.25%、5.33%。由实验数据分类结果可知:多特征融合在一定程度上可以提高近红外脑功能成像分类的精度,且随机森林模型性能稳定,有望解决以往分类精度不高,模型稳定性差的问题,进一步推动脑机接口系统的发展与应用。

关键词：近红外脑血氧随机森林多特征融合分类

Deep amended COPERT model for regional vehicle emission prediction

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Science China(Information Sciences) 2021年第3期64卷 238-240页

作者： Zhenyi XU yu kang Yang CAO Zerui LI Department of Automation University of Science and Technology of China Key Laboratory of Technology in Geo Spatial Information Processing and Application System Chinese Academy of Sciences

Dear editor,The existing methods for regional vehicle emission prediction can be roughly categorized into the classes of classical dispersion models and satellite remote sensing *** plume models, operational street ca...

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Characteristic model based adaptive controller design and analysis for a class of SISO systems

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Science China(Information Sciences) 2016年第5期59卷 176-190页

作者： Jianfei HUANG yu kang Bin MENG yunbo ZHAO Haibo JI State Key Laboratory of Fire Science University of Science and Technology of China Department of Automation University of Science and Technology of China Beijing Institute of Control Engeering College of Information Engineering Zhejiang University of Technology

The design of an adaptive controller and stability analysis of the corresponding closed loop system are discussed for a class of SISO systems based on the characteristic model method. The obtained characteristic model is a second-order slow time-varying linear system with a compress mapping function for the system modeling error. The pole placement method is used to design the controller, and sufficient conditions for the stability of the closed loop system are obtained based on the robust control theory of slow time-varying systems with perturbations. The effectiveness of the proposed method is illustrated by two numerical examples.

关键词： characteristic model modeling error pole placement perturbation analysis sampling system

A networked remote sensing system for on-road vehicle emission monitoring

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Science China(Information Sciences) 2017年第4期60卷 224-231页

作者： yu kang Yan DING Zerui LI Yang CAO yunbo ZHAO State Key Laboratory of Fire Science University of Science and Technology of China Department of Automation University of Science and Technology of China Institute of Advanced Technology University of Science and Technology of China Chinese Research Academy of Environmental Sciences College of Information Engineering Zhejiang University of Technology

Vehicle emissions are a major source of urban air pollution, and therefore a real-time monitoring system can be very useful in analyzing such emission and consequently assisting the policy making process. In this work we discuss the principle and structure of three different types of remote sensing detectors, and also the key techniques to establish a networked remote sensing monitoring system. We finally conclude this paper with data analysis from some preliminary experiments.

关键词： networked system remote sensing vehicle emissions