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Unknown Input Observer Design of Switched Systems Based on Iterative Learning

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Journal of Systems Science & Complexity 2019年第3期32卷 875-887页

作者： CAO Wei sun ming College of Computer and Control Engineering Qiqihar University

For a class of discrete switched systems with unknown input, an unknown input observer design method is proposed under the premise of changes along time axis but no changes along iteration axis. This method applies the iterative learning control thought to the design of unknown input observer, construets the unknown input observer by introducing virtual input signal, and uses the error signal generated from the actual system output and the observer output to correct repetitively the virtual input, which gradually approxima tes the actual unknown input as the it erations increase. Moreover, the convergence of the observer is strictly proved based on contraction mapping theory, as well as the convergence condition is given. The theoretical analysis indicates that designed unknown input observer can accurately estimate the state and unknown input of the system simultaneously. Simulation example further verifies the effectiveness of the proposed algorithm.

关键词： Iterative learning control switched system unknown input observer virtual input

Protein science research in China

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Protein & Cell 2010年第1期1卷 4-5页

作者： ming sun Rui-ming Xu Institute of Biophysics Chinese Academy of Sciences

Proteins are major executors of life processes, carrying out essential and nonessential functions inside and outside of the cell, in species ranging from simple unicellular organisms to mammals. Thus, not surprisingly, studies of structure and function of proteins span the entire spectrum of molecular biology and modern biomedical sciences in general. Due to historical reasons, protein science research in China was isolated and limited in scope until late 1970s. In the last two decades,China has seen an outburst of research activities,government initiatives, and aggregation of human talents in protein science research. This article provides an overview of major initiatives in research funding, investment in infrastructures, and research forces for protein science research in China.

关键词： China science research structure and function molecular biology major government activities processes essential studies species limited simple modern forces scope human span cell two

Properties and photodetector applications of two-dimensional black arsenic phosphorus and black phosphorus

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Science China(Information Sciences) 2021年第4期64卷 120-133页

作者： Ruyue HAN Shun FENG Dong-ming sun Hui-ming CHENG Shenyang National Laboratory for Materials Science Institute of Metal Research Chinese Academy of Sciences School of Materials Science and Engineering University of Science and Technology of China School of Physical Science and Technology ShanghaiTech University Shenzhen Geim Graphene Center Shenzhen International Graduate School Tsinghua University

Two-dimensional(2D) black arsenic phosphorus(b-AsP), as an alloy of black phosphorus(bP) with arsenic, has attracted great attention because of its outstanding electronic and optical properties,including high carrier mobility, tunable bandgap and in-plane anisotropy. B-AsP has a smaller bandgap(0.15–0.3 eV) than the b-P bandgap(0.3–2.0 eV), and thus can be used for mid-infrared *** addition, both of them can form various van der Waals(vdW) heterojunctions with other 2D materials to realize novel functional optoelectronic devices. Here, we compare the basic characteristics of b-AsP and b-P, including crystal structure, optical properties, band structure, electrical properties and stability, and we summarize the update progress of b-AsP in photo detection, including representatives of phototransistor and photodiode devices. In the last part, the future research directions are discussed.

关键词： black arsenic phosphorus crystal structure optical property electrical property photodetector

Iterative learning based fault detection and estimation in nonlinear systems

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Journal of Systems Engineering and Electronics 2012年第3期23卷 419-424页

作者： Wei Cao Wang Cong ming sun College of Automation Harbin Engineering University Harbin 150001 E R. China College of Computer and Control Engineering Qiqihar University Qiqihar 161006 E R. China

Aiming at a class of nonlinear systems that contains faults, a novel iterative learning scheme is applied to fault detec- tion, and a novel algorithm of fault detection and estimation is proposed. This algorithm first constructs residual signals by the output of the practical system and the output of the designed fault tracking estimator, and then uses the residuals and the difference- value signal of the adjacent two residuals to gradually revise the introduced virtual faults, which can cause the virtual faults to close to the practical faults in systems, thereby achieving the goal of fault detection for systems. This algorithm not only makes full use of the existing valid information of systems and has a faster tracking con- vergent speed than the proportional-type （P-type） algorithm, but also calculates more simply than the proportional-derivative-type （PD-type） algorithm and avoids the unstable effects of differential operations in the system. The final simulation results prove the validity of the proposed algorithm.

关键词： iterative learning nonlinear system fault detection fault estimation.

Analysis of HAZMAT truck driver fatigue and distracted driving with warning-based data and association rules mining

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Journal of Traffic and Transportation Engineering(English Edition) 2023年第1期10卷 132-142页

作者： ming sun Ronggui Zhou Chengwu Jiao Road Safety Research Center Research Institute of Highway Ministry of TransportBeijing 100088China

Professional drivers are more frequently exposed to longer driving distance and travel time,leading to a higher possibility of safety risk for distraction and *** widespread and common use of commercial driver monitoring systems(DMS)provides a potential for data *** increases the amount of data characterizing driver behavior that can be used for further safety *** study utilized DMS warning-based data and applied an association rule mining approach to explore risk factors contributing to hazardous materials(HAZMAT)truck driver inattention.A total of 499 HAZMAT truck driver inattentive warning events were used to find rules that will predict the occurrence of driver’s fatigue and ***,Fisher’s exact tests were performed to examine the association between the frequency of driver inattentive behavior warnings and risk ***,support,confidence,and lift values were used as measurements to quantify the relative strength of the association rules generated by the Apriori *** show that speed between 40and 49 km/h,relatively longer travel time(3-6 h),freeway,tangent section,off-peak hour and clear weather condition are found to be highly associated with fatigue driving,while nighttime during 18:00 to 23:59,speed between 70 and 80 km/h,travel time between 1 and 3 h,freeways,acceleration less than 0.5 m/s^(2),visibility greater than 1000 m,and tangent roadway section are found to be highly associated with distracted *** focusing on the specific feature groups,these association rules would help in the development of mitigating distraction and fatigue driving countermeasures and enforcement approaches.

关键词： Traffic safety DMS warning-based data Association rule mining HAZMAT truck driver Distracted driving Fatigue driving

Study on Evaluation Method of Failure Pressure for Pipeline with Axially Adjacent Defects

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China Ocean Engineering 2023年第4期37卷 598-612页

作者： sun ming-ming FANG Hong-yuan DU Xue-ming WANG Wen-hua LI Xin School of Water Conservancy and Transportation Zhengzhou UniversityZhengzhou 450001China National Local Joint Engineering Laboratory of Major Infrastructure Testing and Rehabilitation Technology Zhengzhou 450001China Collaborative Innovation Center of Water Conservancy and Transportation Infrastructure Safety Zhengzhou 450001China Yellow River Laboratory Zhengzhou UniversityZhengzhou 450001China State Key Laboratory of Coastal and Offshore Engineering Dalian University of TechnologyDalian 116024China School of Hydraulic Engineering Faculty of Infrastructure EngineeringDalian University of TechnologyDalian 116024China

The interaction between axially adjacent defects is more significant than that between circumferentially aligned ***,the existing failure pressure assessment methods cannot accurately predict the failure pressure of axial adjacent *** the paper,the finite element model is adopted to analyze the influence of defect size,distribution mode and spacing between adjacent defects on failure pressure.A new failure pressure evaluation method is proposed by establishing the effective depth calculation model of corrosion colony with different distribution *** burst test of X52 pipeline is carried out to verify the applicability of the *** shows that the results of new method are consistent with the test results of pipeline with various defects and steel grades.

关键词： steel pipeline effective depth axially adjacent defects burst test evaluation method

Design and stability analysis of a generalized reduced-order active disturbance rejection controller

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Science China(Technological Sciences) 2022年第2期65卷 361-374页

作者： WANG YongShuai CHEN ZengQiang sun ming Wei sun QingLin College of Artificial Intelligence Nankai UniversityTianjin 300350China Key Laboratory of Intelligent Robotics of Tianjin Tianjin 300350China

Disturbance and uncertainty rejection is a key objective in control system design, and active disturbance rejection control(ADRC)exactly provides an effective solution to this issue. To this end, this paper presents a generalized active disturbance rejection controller for a class of nonlinear uncertain systems with linear output. To be specific, a generalized reduced-order extended state observer(ESO) is proposed to reduce phase delay and complexity of the system, which can take full advantage of the system output. Also, this method includes the existing results with fewer assumptions, and can be applied to systems with any order measurable states or multiple states, even linear combination states. Furthermore, the stability of this approach is guaranteed and demonstrated through matrix transformation and Lyapunov method, and design examples and numerical simulations are given to show the effectiveness and practicability of the method.

关键词： generalized reduced-order ESO active disturbance rejection control(ADRC) linear combination states stability analysis Gronwall-Bellman inequality

Recent developments and applications on high-performance cast magnesium rare-earth alloys

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Journal of Magnesium and Alloys 2021年第1期9卷 1-20页

作者： Guohua Wu Cunlong Wang ming sun Wenjiang Ding National Engineering Research Center of Light Alloy Net Forming and State Key Laboratory of Metal Matrix Composites Shanghai Jiao Tong UniversityShanghai 200240China School of Materials Science and Engineering Jiangsu UniversityZhenjiang 212013Jiangsu ProvinceChina School of Materials Science and Engineering University of Shanghai for Science and TechnologyShanghai 200093China

During the past decades,with the increasing demands in lightweight structural materials,Mg alloys with low density and high performance have been extensively investigated and partly applied in some *** when rare earth(RE)elements are added as major alloying elements to Mg alloys,the alloy strength and creep resistance are greatly improved,which have promoted several series of Mg-RE *** paper reviews the progress and developments of high-performance Mg-RE alloys in recent years with emphasis on cast *** main contents include the alloy design,melt purification,grain refinement,castability,novel liquid casting and semisolid forming approaches,and the industrial applications or trials made of Mg-RE *** review will provide insights for future developments of new alloys,techniques and applications of Mg alloys.

关键词： Magnesium alloys Rare-earth elements High-performance Developments Applications Cast

空间在轨环境下的30cm离子推力器三栅极组件间距变化仿真分析

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宇航学报 2019年第11期40卷 1375-1382页

作者：孙明明耿海王亮郑艺兰州空间技术物理研究所真空技术与物理重点实验室

采用有限元仿真(FEM)与地面热平衡试验验证相结合的方法,计算并模拟了30 cm离子推力器处于在轨环境时,有、无主动热控对三栅极相对位移变化造成的影响,并对目前离子推力器设置的工作启动流程可能造成的打火风险进行了预估。结果显示:三... 详细信息

采用有限元仿真(FEM)与地面热平衡试验验证相结合的方法,计算并模拟了30 cm离子推力器处于在轨环境时,有、无主动热控对三栅极相对位移变化造成的影响,并对目前离子推力器设置的工作启动流程可能造成的打火风险进行了预估。结果显示:三栅极组件的热形变方向均为法向方向,且栅极中心区域的间距最小;在-269℃在轨极限环境温度下,推力器在5 kW工作模式下温度平衡后的屏栅与加速栅最大热态间距为0.14 mm,加速栅和减速栅则已发生贴合;在受太阳辐照以及卫星帆板恒温边界的影响下,栅面最低初始温度为-102℃;当推力器主动热控保证温控点为20℃时,栅面最低启动温度为-25℃,且推力器工作8000s后,屏栅与加速栅、加速栅与减速栅的最小间距分别稳定在0.25 mm和0.20 mm;当推力器主动热控保证温控点为50℃时,推力器工作9000s后,屏栅与加速栅、加速栅和减速栅最小间距分别稳定在0.31 mm和0.30 mm,能够满足0.25 mm的栅极安全打火间距要求。

关键词：离子推力器三栅极组件空间在轨环境栅极间距变化