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A new adaptive Kalman filter for navigation systems of carrier-based aircraft

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Chinese Journal of Aeronautics 2022年第1期35卷 416-425页

作者： Lifei ZHANG Shaoping WANG Maria Sergeevna SELEZNEVA konstantin Avenirovich NEUSyPIN Department of Informatics and Control Systems Bauman Moscow State Technical University Moscow 101000Russia School of Automation Science and Electrical Eingineering Beihamng University Beijing 100083China

The features of carrier-based aircraft’s navigation systems during the approach and landing phases are investigated.A new adaptive Kalman filter with unknown state noise statistics is proposed to improve the accuracy of the INS/GNSS integrated navigation *** adaptive filtering algorithm aims to estimate and adapt the unknown state noise covariance Q in high dynamic conditions,when the measurement noise covariance R is assumed to be known empirically in *** new adaptive Kalman filter based on the innovation sequence and pseudo-measurement vector approach makes it more effective to estimate and adapt *** simulation results and semi-physical experiments show that the application of the proposed adaptive Kalman filter can guarantee a higher estimation accuracy of the state variables.

关键词： Adaptive filters Apriori statistics Deck landing aircraft Innovation sequence State noise covariance

Research Progress and Future Perspectives on Rechargeable Na-O_(2) and Na-CO_(2) Batteries

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Energy & Environmental Materials 2021年第2期4卷 158-177页

作者： Zhi Zheng Chang Wu Qinfen Gu konstantin konstantinov Jiazhao Wang Institute for Superconducting and Electronic Materials University of WollongongWollongong NSW 2522Australia The Australian Synchrotron(ANSTO) 800 Blackburn RoadClayton VIC 3168Australia

Rechargeable sodium–oxygen(Na-O_(2))and sodium–carbon dioxide(Na-CO_(2))batteries have attracted intensive research attention in recent years owing to their advantages of high theoretical energy density,modest cost,abundance of sodium resources,and promising potential for achieving real sodium–air batteries in large-scale energy storage ***,current research on Na-O_(2)and Na-CO_(2)batteries is facing enormous challenges,such as low energy efficiency and limited cycle life,which are restricting their progress at the initial ***,understanding their working principles,and the chemical and electrochemical reactions of the electrodes is indispensable to achieve their practical application and even the goal of true sodium–air *** review aims to provide an overview of the research developments and future perspectives on Na-O_(2)and Na-CO_(2)batteries,which include the major aspects,such as working mechanisms,air cathode materials design strategies,sodium anode protection,and electrolyte ***,the remaining issues and future research directions are also thoroughly discussed and presented.

关键词： anode protection cathode materials electrolytes Na-CO_(2)batteries Na-O_(2)batteries

Rotordynamic prediction of mode order transition when rotor has an overhang

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航空动力学报 2015年第2期30卷 397-409页

作者： konstantin Shaposhnikov HONG Jie ZHANG Da-yi MA yan-hong School of Energy and Power Engineering Beijing University of Aeronautics and Astronautics

Nowadays rotating machinery grows and develops extremely fast due to its multi-branch *** the fields of rotordynamics and rotor balancing had a strong background based on previous experience in order to perform efficient and safe operation for the rotating machines,still there are problems which are hard to be dealt with in some special *** of them is balancing of the rotor with huge *** with overhang is inherent to have console modes,which previously often were observed separately from the other modes in rotordynamic *** such a way console modes,their behavior,order of appearance and interaction with other modes were described in current paper in more *** results confirmed that console modes obey the principle of orthogonality in the same way as all other modes and hence could be efficiently balanced using modal balancing *** results revealed likelihood of such phenomena as modes order transition,when the rotor has an *** a consequence perfectly balanced console rotor could not be so due to modes order transition effect when the bearing stiffness in situ differs from bearing stiffness of balancing *** results will be useful for engineers who are involved in area of rotating machinery vibration tuning for the rotor with huge overhang and benefit them to recognize these modes efficiently and to perform balancing successfully.

关键词：疲劳寿命分散性顺序统计量寿命分散系数小子样

High-resolution photoacoustic microscope for rat brain imaging in vivo

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Chinese Optics Letters 2010年第6期8卷 609-611页

作者：杨孝全蔡鑫 konstantin Maslov 汪立宏骆清铭 Britton Chance Center for Biomedical Photonics Wuhan National Laboratory for OptoelectronicsHuazhong University of Science and Technology Optical Imaging Laboratory Department of Biomedical EngineeringWashington University in Saint LouisSaint Louis63130-4899USA

A reflection-mode photoacoustic microscope（PAM） for rat brain imaging in vivo is constructed.A pulsed laser is used as an excitation source,and a focused ultrasound transducer is adopted to collect the photoacoustic *** scanning is applied to acquire three-dimensional（3D） *** obtained measurements of the lateral and axial resolutions of the microscope are 45 and 15μm,*** imaging depth in the chicken breast tissue is 3.1 mm at a signal-to-noise ratio（SNR） of 20 dB without any signal *** imaging speed is 30 A-line/*** results in vivo demonstrate the capability of 3D imaging of the brain vessels of the rat after removing the skull.

关键词： Acoustic microscopes Laser excitation Photoacoustic effect Photoacoustic microscopy Pulsed laser applications Pulsed lasers Signal to noise ratio Ultrasonic transducers

Numerical study of high-lift hydrofoil near free surface at moderate Froude number

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Journal of Hydrodynamics 2020年第1期32卷 44-53页

作者： Tao Xing konstantin I.Matveev Miles P.Wheeler Department of Mechanical Engineering The University of IdahoMoscowIdahoUSA School of Mechanical and Materials Engineering Washingion State UniversityPullmanWashingtonUSA

Shallow hydrofoils are known to produce lower lift in normal operating conditions in comparison with deep ***,the maximum lift capability of shallow hydrofoils at moderate speeds,which is important for transitional regimes of hydrofoil boats,is studied *** this work,two-dimensional flow around a high-lift hydrofoil at a moderate Froude number is numerically simulated in a broad range attack angles up to the stall occurrence in both single-phase fluid and in the vicinity of free *** is found that nearly the same maximum lift coefficient can be produced by the shallow foil in the modeled condition as by the deep foil,but much higher attack angle is required near the free surface,which also results in larger ***,it is shown that higher Reynolds numbers lead to higher lift coefficients,especially at large attack angles.

关键词： Hydrofoil numerical simulation free surface effect stall

Cooling and energy loss of partially ionized hydrogen gas behind a shock wave

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Research in Astronomy and Astrophysics 2018年第8期18卷 111-116页

作者： Oksana Mikhailovna Belova konstantin Veniaminovich Bychkov Faculty of Physics Lomonosov Moscow State University Sternberg Astronomical Institute Lomonosov Moscow State University

We studied the difference in behavior of total energy and its thermal component during the radiative cooling of partially ionized hydrogen gas. Our calculations were fulfilled for the conditions in the atmosphere of a... 详细信息

关键词： stellar atmospheres shock wave

New family of single-component Ni catalysts for ethylene polymerization to high and ultrahigh molecular weight polyethylene

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Science China Chemistry 2020年第6期63卷 753-754页

作者： Artem A.Antonov Wen-Hua Sun konstantin P.Bryliakov Boreskov Institute of Catalysis Pr.Lavrentieva 5Novosibirsk 630090Russia Novosibirsk State University Pirogova 1Novosibirsk 630090Russia Key Laboratory of Engineering Plastics and Beijing National Laboratory for Molecular Sciences Institute of ChemistryChinese Academy of SciencesBeijing 100190China CAS Research/Education Center for Excellence in Molecular Sciences University of Chinese Academy of SciencesBeijing 100049China

Since the milestone discovery of Ni(II)salicylaldiminate catalysts by Grubbs and co-workers[1],nickel(II)complexes with N,N-and N,O-donor ligands have strengthened their lead in the search for highly active platforms for olefins homo-and copolymerization with various co-monomers,including those with polar groups,to achieve polymers with precisely controlled microstructures[2,3].

关键词： discovery catalysts co-monomers

In-depth improvement of soil at the base of roads on taliks

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Research in Cold and Arid Regions 2015年第5期7卷 475-481页

作者： Alexey y.Burukin Svyatoslav ya.Lutskiy konstantin N.Khripkov Open Joint Stock Company USK MOST (OJSC "USK MOST") Federal State-Funded Educational Institution of Higher Vocational Education Moscow State University of Railway Engineering MGUPS (MIIT)

The article presents a new technological solution to improve the safety of embankment bases on taliks during construction periods. The use of geotextile-sleeved sand columns and geogrids on low-temperature permafrost is investigated. The correlations between mechanical and temperature processes under this in-depth base improvement method are calculated.

关键词： permafrost embankment base improvement geotextile geogrid

Cap snatch prevention:a novel approach to tackle influenza viruses

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Signal Transduction and Targeted Therapy 2023年第6期8卷 2435-2436页

作者： konstantin M.J.Sparrer Frank Kirchhoff Institute of Molecular Virology Ulm University Medical CenterUlmGermany

A recent study published in Science1 by Tsukamoto and colleagues shows that a derivative of tubercidin,a natural product from Streptomyces,selectively inhibits influenza A and B viruses(IAV and IBV,respectively).The compound targets the host RNA methyltransferase MTr1,and thus prevents viral“cap snatching”(Fig.1).These results may help to develop novel drugs that target viral host dependency factors and are thus less likely to induce viral resistance.

关键词： prevention influenza likely