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On extended state Kalman filter-based identification algorithm for aerodynamic parameters

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Control Theory and Technology 2024年第2期22卷 235-243页

作者： Wenyan Bai Ruizhe jia Peng yu Wenchao Xue Beijing Aerospace Automatic Control Institute Beijing100854China School of Automation and Electrical Engineering University of Science and Technology BeijingBeijing100083China Key Laboratory of Knowledge Automation for Industrial Processes Ministry of EducationBeijing100083China Key Laboratory of Systems and Control Institute of Systems ScienceAcademy of Mathematics and Systems ScienceChinese Academy of SciencesBeijing100190China

In this paper, the problem of time-varying aerodynamic parameters identification under measurement noises is studied. By analyzing the key aerodynamic parameters that affect the aircraft control system, a system model with extended states for identifying equivalent aerodynamic parameters is established, and error parameters are extended to the system state, avoiding the difficulty caused by the unknown dynamic in the system. Furthermore, an identification algorithm based on extended state Kalman filter is designed, and it is proved that the algorithm has quasi-consistency, thus, the estimation error can be evaluated in real time. Finally, the simulation results under typical flight scenarios show that the designed algorithm can accurately identify aerodynamic parameters, and has desired convergence speed and convergence precision.

关键词： Aerodynamic parameters Parameter identification Extended state Kalman filter

Boundary Regularity of Isometries Between Infinitely Flat Complex Domains

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Acta Mathematica Sinica,English Series 2024年第6期40卷 1375-1387页

作者： Jin Song LIU Fei tao Hong yu WANG Academy of Mathematics and Systems Science Chinese Academy of SciencesBeijing 100190P.R.China School of Mathematical Sciences University of Chinese Academy of SciencesBeijing 100049P.R.China Beijing International Center for Mathematical Research Peking UniversityBeijing 100871P.R.China School of Science Beijing University of Posts and TelecommunicationsBeijing 100876P.R.China Key Laboratory of Mathematics and Information Networks(Beijing University of Posts and Telecommunications) Ministry of EducationBeijing 100876P.R.China

In this paper we prove that isometries with respect to the Kobayashi metric between certain domains having boundary points at which the boundary is infinitely flat extend continuously to the *** strategy is to reestab... 详细信息

关键词： Boundary extension Kobayashi metric isometries

Structure engineering of cathode host materials for Li-S batteries

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Rare Metals 2024年第4期43卷 1370-1389页

作者： jia-Jun Long Hua yu Wen-Bo Liu School of New Energy and Materials Southwest Petroleum UniversityChengdu610500China School of Mechanical Engineering Sichuan UniversityChengdu610065China

Although lithium-sulfur batteries are one of the favorable candidates for next-generation energy storage devices,a few key challenges that have not been addressed have limited its *** challenges include lithium dendrite growth in the anode side,volume change of the active material,poor electrical conductivity,dissolution and migration of poly sulfides,and slow rate of solid-state reactions in the cathode *** the electrochemical performance of lithium-sulfur batteries is greatly affected by the design of the cathode host material,it has also been widely discussed in addressing the abovementioned *** this paper,three design ideas of cathode host materials in terms of microstructure,crystal structure and electronic structure are introduced and ***,the current progress of these three structural design strategies and their effects on the electrochemical performance of lithium-sulfur batteries are discussed in ***,future directions in the structural design of cathode materials for lithium-sulfur batteries are discussed and further perspectives are provided.

关键词： Lithium-sulfur batteries Structure engineering Cathode Host materials

Optimized parameters of downhole all-metal PDM based on genetic algorithm

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Petroleum Science 2024年第4期21卷 2663-2676页

作者： jia-Xing Lu Ling-Rong Kong yu Wang Chao Feng yu-Lin Gao China University of Geosciences (Beijing) Key Laboratory on Deep Geo-Drilling Technology of Ministry of Natural Resources

Currently, deep drilling operates under extreme conditions of high temperature and high pressure,demanding more from subterranean power motors. The all-metal positive displacement motor, known for its robust performance, is a critical choice for such drilling. The dimensions of the PDM are crucial for its performance output. To enhance this, optimization of the motor's profile using a genetic algorithm has been undertaken. The design process begins with the computation of the initial stator and rotor curves based on the equations for a screw cycloid. These curves are then refined using the least squares method for a precise fit. Following this, the PDM's mathematical model is optimized, and motor friction is assessed. The genetic algorithm process involves encoding variations and managing crossovers to optimize objective functions, including the isometric radius coefficient, eccentricity distance parameter,overflow area, and maximum slip speed. This optimization yields the ideal profile parameters that enhance the motor's output. Comparative analyses of the initial and optimized output characteristics were conducted, focusing on the effects of the isometric radius coefficient and overflow area on the motor's performance. Results indicate that the optimized motor's overflow area increased by 6.9%, while its rotational speed reduced by 6.58%. The torque, as tested by Infocus, saw substantial improvements of38.8%. This optimization provides a theoretical foundation for improving the output characteristics of allmetal PDMs and supports the ongoing development and research of PDM technology.

关键词： Positive displacement motor Genetic algorithm Profile optimization Matlab programming Overflow area

Advances of graphdiyne-supported metal catalysts in thermocatalytic reactions

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Nano Research 2024年第4期17卷 2223-2233页

作者： jia yu Yida Yang yuliang Li Changyan Cao Weiguo Song Beijing National Laboratory for Molecular Sciences CAS Research/Education Center for Excellence in Molecular SciencesLaboratory of Molecular Nanostructures and NanotechnologyInstitute of ChemistryChinese Academy of SciencesBeijing 100190China School of Chemical Sciences University of Chinese Academy of SciencesBeijing 100049China Beijing National Laboratory for Molecular Sciences CAS Research/Education Center for Excellence in Molecular SciencesLaboratory of organic solidsInstitute of ChemistryChinese Academy of SciencesBeijing 100190China

Supported metal catalysts are widely used in the modern chemical *** electronic interaction between supports and active components is of great significance for heterogeneous ***(GDY),a new type of carbon allotrope with sp-hybridized carbon atoms,πconjugate structure,and electron transmission capability,is a promising candidate as catalyst *** years have witnessed the rapid progress of GDY-supported metal catalysts for different catalysis *** that most processes in the current chemical industry are thermocatalytic reactions,we herein give an overview about the advances and particular characteristics of GDY-supported catalysts in these *** geometric structure and electronic properties of GDY are first ***,the synthesis methods for GDY-supported metal catalysts and their applications in thermocatalytic reactions are discussed,in which the effect of electronic interaction on catalytic performance is ***,the current challenges and future directions of GDY-supported metal catalysts for thermocatalysis are *** is expected that this review will enrich our understanding of the advances of GDY as a superior support for metal catalysts in thermocatalytic reactions.

关键词： graphdiyne metal catalysts thermocatalytic reactions heterogeneous catalysis

Small nucleolar RNA and its potential role in the oncogenesis and development of colorectal cancer

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World Journal of Gastroenterology 2024年第2期30卷 115-127页

作者： Yang-Zheng Lan Zheng Wu Wen-jia Chen Ze-Xuan Fang Xin-Ning yu Hua-tao Wu Jing Liu The Breast Center Cancer Hospital of Shantou University Medical CollegeShantou 515041Guangdong ProvinceChina Department of General Surgery The First Affiliated Hospital of Shantou University Medical CollegeShantou 515041Guangdong ProvinceChina

Small nucleolar RNAs(snoRNAs)represent a class of non-coding RNAs that play pivotal roles in post-transcriptional RNA processing and modification,thereby contributing significantly to the maintenance of cellular functions related to protein *** have been discovered to possess the ability to influence cell fate and alter disease progression,holding immense potential in controlling human *** is suggested that the dysregulation of snoRNAs in cancer exhibits differential expression across various cancer types,stages,metastasis,treatment response and/or prognosis in *** the other hand,colorectal cancer(CRC),a prevalent malignancy of the digestive system,is characterized by high incidence and mortality rates,ranking as the third most common cancer *** research indicates that snoRNA dysregulation is associated with CRC,as snoRNA expression significantly differs between normal and cancerous ***,assessing snoRNA expression level and function holds promise for the prognosis and diagnosis of ***,current comprehension of the potential roles of snoRNAs in CRC remains *** review offers a comprehensive survey of the aberrant regulation of snoRNAs in CRC,providing valuable insights into the discovery of novel biomarkers,therapeutic targets,and potential tools for the diagnosis and treatment of CRC and furnishing critical cues for advancing research into CRC and the judicious selection of therapeutic targets.

关键词： Small nucleolar RNAs Colorectal cancer Dysregulation Biomarker

Solvothermal synthesis and adsorption performance of layered boehmite using aluminum chloride and high-alumina fly ash

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Chinese Journal of Chemical Engineering 2024年第6期70卷 280-290页

作者： Jing Wen Ruirui yuan tao jiang Tangxia yu yufan Zhang School of Metallurgy Northeastern UniversityShenyang 110819China Key Laboratory for Ecological Metallurgy of Multimetallic Mineral(Ministry of Education) Northeastern UniversityShenyang 110819China Liaoning Key Laboratory for Metallurgical Sensor and Technology Shenyang 110819China

High alumina fly ash(FAHAl)is a kind of bulk solid waste unique to China,whose availability of high-value aluminum and the threat to the environment makes its high-value utilization *** this work,the alumina containing leaching solution obtained from Na_(2)CO_(3) roasting and HCl leaching of FAHAl was used as the mother liquor to prepare layered boehmite in *** preparation process with AlCl_(3) as the raw material was also *** formation process and mechanism of boehmite,the choice of solvent,along with the adsorption capability of Congo red were analyzed by X-ray diffraction,scanning electron microscopy,Fourier transform infrared spectroscopy,Brunauer-Emmett-Teller method and adsorption *** showed that during the preparation of layered boehmite,the precursor Al(OH)_(3) from the reaction of Al^(3+) and OH-is transformed into boehmiteγ-*** existence of ethanol is beneficial to regulate and promote the growth of boehmite crystal *** water and ethanol are mixed with a volume ratio of 2:1 and used as the solvent,the maximum specific surface area of the boehmite is obtained at 135.7 m^(2)·g^(-1),and 99.16%of Congo red can be absorbed after 10 min when AlCl3 is used as a raw *** purified leaching solution is used as the mother liquid,the crystallinity of boehmite decreases slightly when the pH value decreases from 12.5 to *** pH is 11,the removal efficiency of Congo red reaches a maximum of 72.25%.This process not only achieves the extraction of aluminum and high-value utilization of FAHAl but also provides a thought to prepare layered boehmite with adsorption properties.

关键词： High-alumina fly ash Layered boehmite In-situ preparation Solvothermal synthesis Adsorption High-value utilization

Pullout of the Cylindrical Helicoidal Fiber

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Acta Mechanica Solida Sinica 2024年第3期37卷 444-456页

作者： Chenhan Hu Weihao tao Hongjun yu Qinghua Qin jianshan Wang Department of Mechanics Tianjin UniversityTianjin300054China Department of Astronautic Science and Mechanics Harbin Institute of TechnologyHarbin150001China Department of Materials Science Shenzhen MSU-BIT UniversityShenzhen518172China

The multi-layer cylindrical helicoidal fiber structure(MCHFS)exists widely in biological materials such as bone and wood at the *** typically function as reinforcing elements to enhance the toughness of *** this study,we establish a shear lag-based pullout model of the cylindrical helicoidal fiber(CHF)for investigating interlayer stress transfer and debonding behaviors,with implications regarding the underlying toughening mechanism of *** on the shear lag assumptions,analytical solutions for the stress and displacement fields of the MCHFS during the pullout are derived by considering the CHF as a cylindrically monoclinic material and verified through the 3D finite element *** is found that the helical winding of CHF results in both axial and hoop interlayer shear *** the helical winding angle and the elastic moduli of the fiber and matrix have significant influences on interlayer stress *** work reveals a new interlayer stress transfer mechanism in the MCHFS existing widely in biological materials.

关键词： Cylindrical helicoidal fiber structure Cylindrically monoclinic material Helical winding of fiber Pullout Interlayer stress transfer

Numerical investigations of the interactions between bubble induced shock waves and particle based on OpenFOAM

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Journal of Hydrodynamics 2024年第2期36卷 355-362页

作者： jia-xin yu Jin-sen Hu yu-hang Liu Yi-fan Liu Dan Gao yu-ning Zhang Key Laboratory of Power Station Energy Transfer Conversion and System Ministry of EducationSchool of Energy Power and Mechanical EngineeringNorth China Electric Power UniversityBeijing102206China

The presence of particles and the shock waves generated by the cavitation bubbles can significantly affect the safety and the performance of hydrodynamic *** the present paper,the shock waves generated by cavitation bubble collapsing near the particle are numerically investigated based on the OpenFOAM together with the numerical schlieren for the shock wave *** numerical results reveal that the stand-off distance is one of the paramount factors affecting the interactions between the particle and the shock *** different kinds of shock waves(e.g.,bubble-inception,jet formation,particle reflected and jet-split shock waves)are observed during the bubble collapsing near the *** stand-off distance smaller than 0.5 or larger than 1.1,the maximum pressure at particle surface generated by the bubble growth can surpass those of the collapse stage.

关键词： Particle-bubble interaction shockwaves jetdynamics