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Bayesian Filtering for High-Dimensional State-Space Models With State Partition and Error Compensation

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IEEE/CAA Journal of Automatica Sinica 2024年第5期11卷 1239-1249页

作者： Ke Li Shunyi Zhao Biao Huang Fei Liu key laboratory of advanced process control for light industry(ministry of Education) Institute of AutomationJiangnan UniversityWuxi 214122China Department of Chemical and Materials Engineering University of AlbertaEdmonton AB T6G 2G6Canada

In the era of exponential growth of data availability,the architecture of systems has a trend toward high dimensionality,and directly exploiting holistic information for state inference is not always computationally *** paper proposes a novel Bayesian filtering algorithm that considers algorithmic computational cost and estimation accuracy for high-dimensional linear *** high-dimensional state vector is divided into several blocks to save computation resources by avoiding the calculation of error covariance with immense *** that,two sequential states are estimated simultaneously by introducing an auxiliary variable in the new probability space,mitigating the performance degradation caused by state ***,the computational cost and error covariance of the proposed algorithm are analyzed analytically to show its distinct features compared with several existing *** results illustrate that the proposed Bayesian filtering can maintain a higher estimation accuracy with reasonable computational cost when applied to high-dimensional linear systems.

关键词： filtering estimation error

State Estimator for Linear High-Dimensional Systems With State Partition and Block-Dependent Compensation

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State Estimator for Linear High-Dimensional Systems With Sta...

Preparation and Thermal Stability of AlMoON Based Solar Selective Absorption Coating

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作者： Ke Li Shunyi Zhao Fei Liu key laboratory of advanced process control for light industry (ministry of Education) Institute of Automation Jiangnan University

This paper proposes a Bayesian estimation scheme with block-dependent compensation for linear high-dimensional systems. The state vector is divided into blocks by considering the relationship of state variables in time series and physical interpretation to reduce the underlying computational cost. However, blocking states damages the original system and introduces systematic errors. Consequently, the divided state blocks are compensated by introducing distinct compensation coefficients to improve state estimation accuracy. Considering the difference and uniqueness of state blocks, the distinct compensation coefficients are adaptively adjusted and updated over time to ensure higher accuracy of state estimation. Simulation results of numerical example are used to evaluate the performance of the proposed algorithm. It shows that the proposed algorithm possesses moderate computational cost and higher estimation accuracy compared with the existing methods.

关键词： State estimation Bayesian inference Block-dependent compensation Linear high-dimensional systems

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Journal of Wuhan University of Technology(Materials Science) 2024年第4期39卷 854-862页

作者：闵捷 YUAN Wenxu CHEN Yufei LAN Yapeng YAN Mengdi LIU Hanze CHENG Xudong 代路 Hubei Provincial key laboratory of Green Materials for light industry Hubei University of TechnologyWuhan 430068China Col-laborative Innovation Center of Green light-weight Materials and processing Hubei University of TechnologyWuhan 430068China School of Materials and Chemical Engineering Hubei University of TechnologyWuhan 430068China School of industrial Design Hu-bei University of TechnologyWuhan 430068China State key laboratory of advanced Technology for Materials Synthesis and process-ing Wuhan University of TechnologyWuhan 430070China Science and Technology on Thermal Energy and Power laboratory Wuhan Second Ship Design&Research InstituteWuhan 430205China

AlMoON based solar selective absorption coatings were deposited on stainless steel substrate by magnetron *** coatings included infrared reflection layer Mo,absorption layer AlMoN,absorption layer AlMoON and antireflection layer AlMoO from bottom to *** surface of the deposited coatings is flat without obvious *** absorptivity and emissivity are 0.896 and 0.09,respectively,and the quality factor is *** heat treatment at 500℃-36 h,the surface roughness of the coating increases,a small number of cracks and other defects appear,and the broken part is still attached to the coating surface.A certain degree of element diffusion occurs in the coatings,resulting in the decline of the optical properties of the *** absorptivity and emissivity are 0.883 and 0.131,respectively,the quality factor is 7.06,and the PC value is *** coatings do not fail under this condition and have certain thermal stability.

关键词： AlMoON coating preparation thermal stability

An aircraft brake control algorithm with torque compensation based on RBF neural network

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Chinese Journal of Aeronautics 2024年第1期37卷 438-450页

作者： Ning BAI Xiaochao LIU Juefei LI Zhuangzhuang WANG Pengyuan QI Yaoxing SHANG Zongxia JIAO School of Automation Science and Electrical Engineering Beihang UniversityBeijing 100191China Science and Technology on Aircraft control laboratory Beihang UniversityBeijing 100191China key laboratory of advanced Aircraft Systems(Beihang University) Ministry of Industry and Information TechnologyBeijing 100091China Research Institute for Frontier Science Beihang UniversityBeijing 100191China Ningbo Institute of Technology of Beihang University Ningbo 315800China Tianmushan laboratory Xixi Octagon CityYuhang DistrictHangzhou 310023China

The wheel brake system of an aircraft is the key to ensure its safe landing and rejected takeoff.A wheel’s slip state is determined by the brake torque and ground adhesion torque,both of which have a large degree of *** is this nature that brings upon the challenge of obtaining high deceleration rate for aircraft brake *** overcome the disturbances caused by the above uncertainties,a braking control law is designed,which consists of two parts:runway surface recognition and wheel’s slip state *** runway surface recognition,the identification rules balancing safety and braking efficiency are defined,and the actual identification process is realized through recursive least square method with forgetting *** slip state tracking,the LuGre model with parameter adaptation and a brake torque compensation method based on RBF neural network are proposed,and their convergence are *** effectiveness of our control law is verified through simulation and ground *** in the experiments on the ground inertial test bench,compared to the improved pressure-biased-modulation(PBM)anti-skid algorithm,fewer wheel slips occur,and the average deceleration rate is increased by 5.78%,which makes it a control strategy with potential for engineering applications.

关键词： Aircraft landing Brakes Disturbance observer Neural networks Runway identification

Fabrication of dense SiBCN monolith at a lower temperature and its high-temperature performance

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Journal of advanced Ceramics 2024年第8期13卷 1198-1211页

作者： Zi-Bo Niu Daxin Li Dechang Jia Zhihua Yang Kunpeng Lin Yan Wang Paolo Colombo Ralf Riedel Yu Zhou Institute for advanced Ceramics School of Materials Science and EngineeringHarbin Institute of TechnologyHarbin 150080China key laboratory of advanced Structural-Function Integrated Materials and Green Manufacturing Technology Ministry of Industry and Information TechnologyHarbin 150080China State key laboratory of advanced Welding and Joining Harbin Institute of TechnologyHarbin 150080China Department of industrial Engineering University of PadovaPadova 3513iItaly Department of Materials Science and Engineering The Pennsylvania State UniversityUniversity Park 16802USA Institute of Materials Science Darmstadt University of TechnologyDarmstadt 64287Germany School of Materials Science and Engineering Harbin Institute of Technology(Shenzhen)Shenzhen 518055China

In this study,a crack-free pyrolysis process of partially cured precursor powder compacts was developed to prepare dense silicon boron carbonitride(SiBCN)monoliths at much lower temperatures(1300℃),thereby circumventing the challenges of sintering densification(>1800℃).Unlike the elastic fracture in over-cured precursors or the viscoelastic deformation in under-cured precursors,the partially cured precursor,exhibiting elastic-plastic deformation behavior,facilitates limited nanoscale pore formation in a dense structure,achieving a balance between crack-free pyrolysis and *** to SiBCN derived from the over-cured precursor(σ=~159 MPa,K_(IC)=1.9 MPa:m^(1/2),Vickers hardness(HV)=7.8 GPa,and E=122 GPa),the resulting SiBCN monolith exhibited significantly improved mechanical properties(σ=~304 MPa,K_(IC)=3.7 MPa-m12,HV=10.6 GPa,and E=161 GPa)and oxidation *** addition,this study investigated the high-temperature performance of SiBCN monoliths,including crystallization and oxidation,and determined the oxidation kinetics induced by pore structure healing and the different oxidation mechanisms of Si-C-N and B-C-N clusters in the amorphous *** to its unique composition and structure,the SiBCN ceramic oxide layer exhibits exceptional self-healing effects on repairing the nanoporous system in the initial stage and shows outstanding high-temperature stability during prolonged oxidation,mitigating adverse effects from bubble formation and *** to the nanoporous structure,the oxidation rate is initially controlled by gas diffusion following a linear law before transitioning to oxide layer diffusion characterized by a parabolic ***,due to different valence bond configurations,Si-C-N transforms into an amorphous SiCNO structure after phase separation,unlike the nucleation and growth of residual B-N-C.

关键词： silicon boron carbonitride(SiBCN)ceramics crack-free pyrolysis amorphous structure oxidation mechanisms kinetic law

A novel“Snowflake”--rGO-CuO for ultrasonic degradation of rhodamine and methyl orange

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Nano Materials Science 2024年第3期6卷 365-373页

作者： Yitong Wang Yuhua Wang Zuzhao Xiong Xifei Li Hubei Province key laboratory of Science in Metallurgical process Wuhan University of Science and TechnologyWuhan430081China Department of Engineering and Technology Wuhan College of Foreign Languages&Foreign AffairsWuhan430070China key laboratory of advanced Batteries Materials for Electric Vehicles of China Petroleum and Chemical industry Federation School of Materials Science and EngineeringXi'an University of TechnologyXi'an710048China

Graphene-doped CuO(rGO-CuO)nanocomposites with flower shapes were prepared by an improved solvothermal *** samples were characterized by X-ray diffraction,X-ray photoelectron spectroscopy and UV–visible *** active species in the degradation reaction of rGO-CuO composites under ultrasonic irradiation were detected by electron paramagnetic *** the basis of comparative experiments,the photodegradation mechanisms of two typical dyes,Rhodamine B(Rh B)and methyl orange(MO),were *** results demonstrated that the doped CuO could improve the degradation *** catalytic degradation efficiency of rGO-CuO(2:1)to rhodamine B(RhB)and methyl orange(MO)reached 90%and 87%respectively,which were 2.1 times and 4.4 times of the reduced graphene *** the first-principles and other theories,we give the reasons for the enhanced catalytic performance of rGO-CuO:combined with internal and external factors,rGO-CuO under ultrasound could produce more hole and active sites that could interact with the OH·in pollutant molecules to achieve *** rGO-CuO nanocomposite has a simple preparation process and low price,and has a high efficiency of degrading water pollution products and no secondary pollution *** has a low-cost and high-efficiency application prospect in water pollution industrial production and life.

关键词： rGO-CuO Nanocomposites Characterization Nanomaterial catalyst First principle

An electromagnetic semi-active dynamic vibration absorber for thin-walled workpiece vibration suppression in mirror milling

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Applied Mathematics and Mechanics(English Edition) 2024年第8期45卷 1315-1334页

作者： Jianghua KONG Bei DING Wei WANG Zhixia WANG Juliang XIAO Hongyun QIU School of Mechanical Engineering Tianjin UniversityTianjin 300350China Tianjin key laboratory of Nonlinear Dynamics and control Tianjin 300350China key laboratory of Modern Mechanisms and Equipment Design of the State ministry of Education Tianjin UniversityTianjin 300350China

As critical components of aircraft skins and rocket fuel storage tank shells,large thin-walled workpieces are susceptible to vibration and deformation during machining due to their weak local *** address these challenges,we propose a novel tunable electromagnetic semi-active dynamic vibration absorber(ESADVA),which integrates with a magnetic suction follower to form a followed ESADVA(follow-ESADVA)for mirror *** system combines a tunable magnet oscillator with a follower,enabling real-time vibration absorption and condition feedback throughout the milling ***,the device supports self-sensing and frequency adjustment by providing feedback to a linear actuator,which alters the distance between *** resolves the traditional issue of being unable to directly monitor vibration at the machining point due to space constraints and tool *** frequency shift characteristics and vibration absorption performance are comprehensively *** and experimental results demonstrate that the prototyped follow-ESADVA achieves frequency synchronization with the milling tool,resulting in a vibration suppression rate of approximately 47.57%.Moreover,the roughness of the machined surface decreases by18.95%,significantly enhancing the surface *** results of this work pave the way for higher-quality machined surfaces and a more stable mirror milling process.

关键词： semi-active dynamic vibration absorber(SADVA) mirror milling selfsensing vibration absorption tuning thin-walled workpiece

Development and prospects of molten steel deoxidation in steelmaking process

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International Journal of Minerals,Metallurgy and Materials 2024年第1期31卷 18-32页

作者： Zhongliang Wang Yanping Bao State key laboratory of advanced Metallurgy University of Science and Technology BeijingBeijing 100083China

In the long traditional process of steelmaking,excess oxygen is blown into the converter,and alloying elements are used for *** inevitably results in excessive deoxidation of products remaining within the steel liquid,affecting the cleanliness of the *** the increasing requirements for steel performance,reducing the oxygen content in the steel liquid and ensuring its high cleanliness is *** more than a hundred years of development,the total oxygen content in steel has been reduced from approximately 100×10^(-6)to approximately 10×10^(-6),and it can be controlled below 5×10^(-6)in some steel grades.A relatively stable and mature deoxidation technology has been formed,but further reducing the oxygen content in steel is no longer significant for improving steel *** research team developed a deoxidation technology for bearing steel by optimizing the entire conventional *** technology combines silicon–manganese predeoxidation,ladle furnace diffusion deoxidation,and vacuum final *** successfully conducted industrial experiments and produced interstitial-free steel with natural decarbonization ***-aluminum deoxidation was found to control the oxygen content in bearing steel to between 4×10^(-6) and 8×10^(-6),altering the type of inclusions,eliminating large particle Ds-type inclusions,improving the flowability of the steel liquid,and deriving a higher fatigue *** natural decarbonization predeoxidation of interstitial-free steel reduced aluminum consumption and production costs and significantly improved the quality of cast billets.

关键词： steel deoxidation deoxidizer metallurgical equipment bearing steel IF steel

New steelmaking process based on clean deoxidation technology

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International Journal of Minerals,Metallurgy and Materials 2024年第6期31卷 1249-1262页

作者： Zhongliang Wang Yanping Bao State key laboratory of advanced Metallurgy University of Science and Technology BeijingBeijing 100083China

After the converter steelmaking process,a considerable number of ferroalloys are needed to remove dissolved oxygen from the molten steel,but it also forms a lot of oxide inclusions that cannot be completely *** the same time,it increases the carbon emis-sions in the steel production *** years of research,our team have developed a series of clean deoxidation technologies,includ-ing carbon deoxidation,hydrogen deoxidation,and waste plastic deoxidation of molten steel to address the aforementioned *** this study,thermodynamic calculations and laboratory experiments were employed to verify that carbon and hydrogen can reduce the total oxygen content in the molten steel melt to below 5×10^(-6) and 10×10^(-6),*** analysis of the deoxidation mechanisms and ef-fects of polyethylene and polypropylene was also *** addition,the applications of carbon deoxidation technology in different steels with the hot-state experiment and industrial production were discussed *** carbon deoxidation experimental results of different steels were as follows:(1)the oxygen content of bearing steel was effectively controlled at 6.3×10^(-6) and the inclusion number density was lowered by 74.73%compared to aluminum deoxidized bearing steel;(2)the oxygen content in gear steel was reduced to 7.7×10^(-6) and a 54.49%reduction of inclusion number density was achieved with almost no inclusions larger than 5μm from the average level of industry gear steels;(3)a total oxygen content of M2 high-speed steel was as low as 3.7×10^(-6).In industrial production practice,car-bon deoxidation technique was applied in the final deoxidation stage for non-aluminum deoxidized bearing steel,and it yielded excellent results that the oxygen content was reduced to below 8×10^(-6) and the oxide inclusions in the steel mainly consist of silicates,along with small amounts of spinel and calcium aluminate.

关键词： clean deoxidation carbon deoxidation hydrogen deoxidation waste plastics deoxidation