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Autonomous Recommendation of Fault Detection Algorithms for Spacecraft

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IEEE/CAA Journal of Automatica Sinica 2024年第1期11卷 273-275页

作者： wenbo li Baoling Ning the National Key Laboratory of Science and Technology on Space Intelligent Control Beijing Institute of Control EngineeringBeijing 100094China the School of Data Science and Technology Heilongjiang UniversityHarbin 150001China

Dear Editor, This letter deals with the problem of algorithm recommendation for online fault detection of spacecraft. By transforming the time series data into distributions and introducing a distribution-aware measure, a principal method is designed for quantifying the detectabilities of fault detection algorithms over special datasets.

关键词： fault introducing letter

Rb-Sr isotopic dating of sphalerite from the giant Huize Zn-Pb ore field, Yunnan Province, Southwestern China

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Chinese Journal Of Geochemistry 2009年第1期28卷 70-75页

作者： li wenbo Laboratory of Orogenic Belts and Crustal Evolution Peking University Beijing 100871 China

The giant Huize Zn-Pb ore field in Yunnan Province, southwestern China, comprises the Qilinchang and Kuangshanchang deposits. The deposits are large in scale (more than 5 Mt of Zn and Pb) and high in grade (average grade of total Zn and Pb is 30%). Reported in this paper are the results of Rb-Sr isotopic dating of sphalerite from this ore field. Two precise ages (223.5±3.9 Ma and 226±6.4 Ma) have been obtained from two isochrons. These two ages are close to the reported ages of native copper mineralizations related to the Emeishan flood basalts in this region, which are 226 Ma to 228 Ma. Previous studies showed that the magnitude of uplift resultant from the Emeishan flood basalts is greater than 1000 m, indicating that the Kuangshanchang and Qilinchang deposits were formed during the same geological event and originated by fluid migration during uplifting resultant from the Emeishan flood basalts.

关键词： Zn-Pb法油气成藏过程同位素测年方法

Adjustable stiffness elastic composite soft actuator for fast-moving robots

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Science China(Technological Sciences) 2021年第8期64卷 1663-1675页

作者： GUO XinYu li wenbo ZHANG WenMing State Key Laboratory of Mechanical System and Vibration School of Mechanical EngineeringShanghai Jiao Tong UniversityShanghai200240China

The application of soft pneumatic actuators is typically hindered by the low strength and slow response speed caused by their intrinsic material limitation and unstressed stable *** this work,we present a design strategy for improving the performance and response speed for Pneu-Nets actuators by incorporating adjustable elastic components to form the elastic composite pneumatic actuator(ECPA).The elastic energy storage of the elastic component is implemented to enhance the capability and speed up the response of ECPA and pre-bend the *** to the design principle,the fully-flexible ECPA is easy to manufacture and *** modeling and experiments are implemented to reveal the fast response characteristics and adjustable mechanical characteristics of *** results show that the deflation response speed of ECPA is increased by at least 3.1 times with the action of elastic components,what is more,the stiffness of ECPA is increased by 22 *** on the ECPA,two kinds of locomotion robots including a running robot(runs at an average locomotion speed of 6.3 BL/s(body lengths,BL))and an underwater swimming robot(achieves an average speed of 1.1 BL/s)are *** fast-moving robots both demonstrate high-speed mobility because of the rapid response and high strength of ECPA.

关键词： pneumatic actuator fast response adjustable stiffness pre-bending actuator fast-moving robots

EFFICIENT NONNEGATIVE MATRIX FACTORIZATION VIA MODIFIED MONOTONE BARZILAI-BORWEIN METHOD WITH ADAPTIVE STEP SIZES STRATEGY

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Journal of Computational Mathematics 2023年第5期41卷 866-878页

作者： wenbo li Jicheng li Xuenian liu Department of Applied Mathematics Xi’an University of TechnologyXi’an 710054China College of Mathematics and Statistics Xi’an Jiaotong UniversityXi’an 710049China

In this paper,we develop an active set identification *** means of the active set technique,we present an active set adaptive monotone projected Barzilai-Borwein method(ASAMPBB)for solving nonnegative matrix factorization(NMF)based on the alternating nonnegative least squares framework,in which the Barzilai-Borwein(BB)step sizes can be adaptively picked to get meaningful convergence rate *** get optimal step size,we take into account of the curvature *** addition,the larger step size technique is exploited to accelerate convergence of the proposed *** global convergence of the proposed method is analysed under mild ***,the results of the numerical experiments on both synthetic and real-world datasets show that the proposed method is effective.

关键词： Adaptive step sizes Alternating nonnegative least squares Monotone projected Barzilai-Borwein method Active set strategy Larger step size

Reconfigurability evaluation method for input-constrained control systems

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Journal of Systems Engineering and Electronics 2021年第5期32卷 1023-1030页

作者： TU Yuanyuan WANG Dayi li wenbo Beijing Institute of Control Engineering China Academy of Space TechnologyBeijing 100190China Beijing Institute of Spacecraft System Engineering China Academy of Space TechnologyBeijing 100190China

This paper proposes a quantitative reconfigurability evaluation method for control systems with actuator saturation and additive faults from the perspective of system *** the saturated feedback law in the convex hull of a group of auxiliary linear controls,the sufficient reconfigurability conditions for the system under additive faults are derived using invariant *** conditions are then expressed as linear matrix inequalities(LMIs)and applied to quantify the degree of reconfigurability for the fault *** largest fault magnitude for which the system can be stabilized,the largest initial state domain from which all the trajectories are convergent,and the minimum final state domain to which the trajectories will converge are *** effectiveness of the proposed method is illustrated through an application example.

关键词： control reconfigurability additive fault actuator saturation invariant set fault-tolerant control

Alternative lead-free mixed-valence double perovskites for high-efficiency photovoltaic applications

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Journal of Energy Chemistry 2023年第9期84卷 347-353页

作者： wenbo li Yuheng li Zilong Zhang Peng Gao CAS Key Laboratory of Design and Assembly of Functional Nanostructures and Fujian Provincial Key Laboratory of NanomaterialsFujian Institute of Research on the Structure of MatterChinese Academy of SciencesFuzhou 350002FujianChina Laboratory for Advanced Functional Materials Xiamen Institute of Rare Earth MaterialsHaixi InstituteChinese Academy of SciencesXiamen 361021FujianChina University of Chinese Academy of Sciences Beijing 100049China

Lead-based organic-inorganic hybrid perovskites have exhibited great potential in photovoltaics,achieving power conversion efficiencies(PCEs) exceeding 25%.However,the toxicity of lead and the instability of these materials under moist conditions pose significant barriers to large-scale *** overcome these limitations,researchers have proposed mixed-valence double perovskites,where Cs_(2)Au~ⅠAu~ⅢI_6 is a particularly effective absorber due to its suitable band gap and high absorptance *** further extend the scope of these lead-free materials,we varied the trivalent gold ion and halogen anion in Cs_(2)Au~ⅠAu~ⅢI_6,resulting in 18 new structures with unique ***,using first-principles calculations and elimination criteria,we identified four materials with ideal band gaps,small effective carrier mass,and strong anisotropic optical *** to theoretical modeling,Cs_(2)AuSbCl_6,Cs_(2)AuInCl_6,and Cs_(2)AuBiCl_6 are potential candidates for solar cell absorbers,with a spectroscopic limited maximum efficiency(SLME) of approximately 30% in a 0.25 μm-thick *** three compounds have not been previously reported,and therefore,our work provides new insights into potential materials for solar energy *** aim for this theoretical exploration of novel perovskites to guide future experiments and accelerate the development of high-performance photovoltaic devices.

关键词： Mixed valence double perovskite Theoretical calculation Electronic configuration Photovoltaic performance

The multistage genesis of the giant Dongshengmiao Zn-Pb-Cu deposit in western Inner Mongolia,China:Syngenetic stratabound mineralization and metamorphic remobilization

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Geoscience Frontiers 2016年第3期7卷 529-542页

作者： Richen Zhong wenbo li Civil and Environmental Engineering School University of Science and Technology Beijing Key Laboratory of Orogenic Belts and Crustal Evolution School of Earth and Space SciencesPeking University

The genesis of the giant Dongshengmiao in the northern margin of the North China Block has been debated since its discovery in the 1950 s,because it shows geological and geochemical characteristics with both syngenetic and epigenetic *** has geological settings and sulfur and lead isotopic compositions that are similar with typical SEDEX（sedimentary exhalative） deposit,while the Zn-Pb-Cu mineralization was controlled by shear deformation and metamorphism,showing similarities with orogenic-type *** this contribution,both the syngenetic and epigenetic features of the Dongshengmiao are envisaged,and accounted for in the context of a genetic model with two metallogenic *** pyrite at the Dongshengmiao was mostly recrystallized during metamorphism,but finegrained texture was locally preserved,indicating its syngenetic *** the contrary,all the Zn-Pb-Cu ores observed in this study show characteristics of epigenetic hydrothermal mineralization that controlled by metamorphism and accompanying shear *** sulfur and lead isotopic compositions of sphalerite and galena indicate that they were in situ remobilized from a syngenetic stratabound source,and the oxygen and hydrogen isotopic ratios of ore-fluid indicate that the large-scale remobilization was assisted by metamorphic *** thermodynamic modeling indicates that the orefluid during remobilization has a great potential of transporting *** may account for the abnormally enriched Cu in the remobilized SEDEX *** metamorphic fluid might strip Cu from the fluid source during devolatilization,and overprint it on the Zn-Pb orebodies during remobilization.A secondary flowthrough modeling reveals that Zn- and Cu-sulfides would be preferentially redistributed in Fe-rich carbonates during remobilization,as a result of fluid-rock ***,a multistage genetic model is *** the development of the Proterozoic rift,stratabound Zn-Pb mineralization to

关键词： SEDEX Zn-Pb-Cu Metamorphism Remobilization Orogenic-type deposit

On Hierarchical Compensation Based Active Disturbance Rejection Control for ACMM Problem of Spacecraft

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Journal of Systems Science & Complexity 2023年第4期36卷 1480-1497页

作者： liU Ping CHEN Seng XUE Wenchao li wenbo School of Aeronautics and Astronautics Sun Yat-sen UniversityShenzhen 518107China LSC NCMISAcademy of Mathematics and Systems ScienceChinese Academy of SciencesBeijing 100190China Shenzhen Faroad Intelligent Equipment Co. LtdShenzhen 518105China School of Mathematics and Information Science Shaanxi Normal UniversityXi’an 710062China School of Mathematical Sciences University of Chinese Academy of SciencesBeijing 100049China Beijing Institute of Control Engineering China Academy of Space TechnologyBeijing 100086China

The attitude control and momentum management(ACMM)problem is quite fundamental for many spacecrafts including space stations,sky laboratories and *** of single attitude control problem,ACMM problem has to take account of both disturbance rejection and energy *** paper studies the ACMM problem for general spacecraft.A practical active disturbance rejection control architecture is proposed with hierarchical compensation to different kinds of uncertain dynamics or *** particular,by integrating RLS into ESO,the constant and sinusoidal disturbance terms to be compensated are ***,the LQR law is implemented to achieve the desired performance of control systems after disturbance ***,quantitative performances of the generalized ESO,the RLS algorithm and the closed-loop tracking system are rigorously ***,the results under 9-DOF semi-physical test environment show the effectiveness of our control method.

关键词： Active disturbance rejection control attitude control and momentum management extended state observer hierarchical compensation

Subduction-zone peridotites and their records of crust-mantle interaction

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Science China Earth Sciences 2019年第7期62卷 1033-1052页

作者： Jianping ZHENG Qing XIONG Yi ZHAO wenbo li School of Earth Sciences State Key Laboratory of Geological Processes and Mineral ResourcesChina University of Geosciences

Subduction is the core process of plate tectonics. The mantle wedge in subduction-zone systems represents a key tectonic unit, playing a significant role in material cycling and energy exchange between Earth's layers. This study summarizes research progresses in terms of subduction-related peridotite massifs, including supra-subduction zone(SSZ) ophiolites and mantle-wedge-type(MWT) orogenic peridotites. We also provide the relevant key scientific questions that need be solved in the future. The mantle sections of SSZ ophiolites and MWT orogenic peridotites represent the mantle fragments from oceanic and continental lithosphere in subduction zones, respectively. They are essential targets to study the crust-mantle interaction in subduction zones. The nature of this interaction is the complex chemical exchanges between the subducting slab and the mantle wedge under the major control of physical processes. The SSZ ophiolites can record melt/fluid-rock interaction, metamorphism,deformation, concentration of metallogenic elements and material exchange between crust and mantle, during the stages from the generation of oceanic lithosphere at spreading centers to the initiation, development, maturation and ending of oceanic subduction at continental margins. The MWT orogenic peridotites reveal the history of strong metamorphism and deformation during subduction, the multiple melt/fluid metasomatism(including silicatic melts, carbonatitic melts and silicate-bearing C-HO fluids/supercritical fluids), and the complex cycling of crust-mantle materials, during the subduction/collision and exhumation of continental plates. In order to further reveal the crust-mantle interaction using subduction-zone peridotites, it is necessary to utilize high-spatial-resolution and high-precision techniques to constrain the complex chemical metasomatism, metamorphism,deformation at micro scales, and to reveal their connections with spatial-temporal evolution in macro-scale tectonics.

关键词： Subduction zone Ophiolite Orogenic peridotite Mantle wedge Metasomatism Crust-mantle interaction