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Computer vision tasks for intelligent aerospace perception: An overview

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Science China(Technological Sciences) 2024年第9期67卷 2727-2748页

作者： CHEN Huilin SUN QiYu li fangfei TANG Yang School of Information Science and Engineering East China University of Science and TechnologyShanghai 200237China School of Mathematics East China University of Science and TechnologyShanghai 200237China

Computer vision tasks are crucial for aerospace missions as they help spacecraft to understand and interpret the space environment,such as estimating position and orientation, reconstructing 3D models, and recognizing objects, which have been extensively studied to successfully carry out the missions. However, traditional methods like Kalman filtering, structure from motion, and multi-view stereo are not robust enough to handle harsh conditions, leading to unreliable results. In recent years, deep learning(DL)-based perception technologies have shown great potential and outperformed traditional methods, especially in terms of their robustness to changing environments. To further advance DL-based aerospace perception, various frameworks, datasets,and strategies have been proposed, indicating significant potential for future applications. In this survey, we aim to explore the promising techniques used in perception tasks and emphasize the importance of DL-based aerospace perception. We begin by providing an overview of aerospace perception, including classical space programs developed in recent years, commonly used sensors, and traditional perception methods. Subsequently, we delve into three fundamental perception tasks in aerospace missions: pose estimation, 3D reconstruction, and recognition, as they are basic and crucial for subsequent decision-making and control. Finally, we discuss the limitations and possibilities in current research and provide an outlook on future developments,including the challenges of working with limited datasets, the need for improved algorithms, and the potential benefits of multisource information fusion.

关键词： deep learning perception aerospace missions pose estimation 3D reconstruction recognition

Ultrafast investigation of room temperature valley polarization in“optical bilayer”WS_(2)

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Science China(Technological Sciences) 2024年第1期67卷 91-97页

作者： ZHAO LeYi WANG Hai liU TianYu li fangfei ZHOU Qiang WANG HaiYu Synergetic Extreme Condition High-Pressure Science Center State Key Laboratory of Superhard MaterialsCollege of PhysicsJilin UniversityChangchun 130012China State Key Laboratory of Integrated Optoelectronics College of Electronic Science and EngineeringJilin UniversityChangchun 130012China

Monolayer transition metal dichalcogenides(TMDCs)have become a promising platform in valleytronics due to possessing the regulatable valley degrees of ***,as a result of the rapid intervalley scattering,it is difficult to measure the PL valley polarization of monolayer TMDCs at room temperature,which limits their application in valleytronics ***,we report a room temperature photoluminescence(PL)valley polarization up to 3.73%in an“optical bilayer”WS_(2)formed by transferring monolayer WS_(2)onto flat Ag ***,in the transient absorption(TA)measurements,a remarkably long valley depolarization lifetime is ***,we demonstrate the valley properties of such“optical bilayer”WS_(2)resemble actual bilayer WS_(2),in which the robust valley polarization can be attributed to the phonons depletion effect and the blocked interlayer hopping *** peculiar valley features in“optical bilayer”WS_(2)provide a particularly simple method to enhance valley control at room temperature.

关键词： valleytronics optical bilayer transient absorption tungsten disulfide

Synthesis and Electrochemical Properties of a Novel Poly（ether sulfone） with Oligoaniline Pendants

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Chemical Research in Chinese Universities 2015年第6期31卷 1066-1071页

作者： li fangfei WANG Jiayu ZHOU Mingjuan liU Xincai WANG Ce CHAO Danming State Key Laboratory of Superhard Materials Jilin University Changchun 130012 R R. China College of Chemistry Jilin University Changchun 130012 P. R. China

A novel poly（ether sulfone） with oligoaniline pendants（PESOP） was prepared by KaCO3-mediated nucleophilic polycondensation and characterized with Fourier-transform infrared spectrometry（FTIR）, 1H nuclear magnetic resonance（1H NMR） and gel permeation chromatography（GPC）. The cyclic voltammetry（CV） curve of PESOP reveals the reversible electroactivity. In the electrochromism study, PESOP film exhibited good electroch- romic properties with a high contrast value, moderate switching time and acceptable coloration efficiency. After running 1000 cycles, the PESOP/indium-tin oxide（ITO） electrochromic device remained unchanged except for the drifting of base line, which certified its good electro-photo stability of the fabricated electrochromic device. Moreover, the polarization technique and electrochemical impedance spectroscopy（EIS） were used to study the anticorrosion performance of PESOP coatings on the cold rolled steel（CRS） in a 5%（mass fraction） NaCI solution. All the results indicate that the obtained PESOP is a competitive candidate as anticorrosion material.

关键词： Electroactive Oligoaniline Electrochromism Anticorrosion

Adaptive Neural Output Feedback Control for Nonstrict-Feedback Nonlinear Systems with Quantized Input 36

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Adaptive Neural Output Feedback Control for Nonstrict-Feedba...

Optical phonon behavior and magnetism of columbite Zn0.8Co0.2Nb2O6

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作者： Yan Dong Zhaoxu Yu fangfei li Key Laboratory of Advanced Control and Optimization for Chemical Process of Ministry of Education East China University of Science and Technology Department of Mathematics East China University of Science and Technology

ISBN: (纸本)9781538629185

This paper focuses on the problem of adaptive output feedback tracking control for a class of nonstrict-feedback nonlinear systems with unknown control coefficients and quantized input. The difficulty from the unknown control direction is solved by using the linear state transformation and the Nussbaum gain function（NGF） approach. Based on the combination of input-driven observer, backstepping technique, neural network（NN） parametrization and variable separation method, a novel adaptive output feedback quantized control scheme involving only one adaptive parameter is developed for such systems. The designed quantized controller ensures that all signals of closed-loop systems are semi-globally uniformly ultimately bounded（SGUUB）, and the tracking error converges to an adjustable neighborhood of the origin. Finally, a numerical example is provided to demonstrate the effectiveness of the proposed control design.

关键词： Nonstrict-feedback systems quantized input signal output feedback adaptive control unknown control direction

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Chinese Physics B 2019年第12期28卷 56-59页

作者： liang li Xiaohan Wang Ying liu fangfei li Qiang Zhou Tian Cui State Key Laboratory of Superhard Materials College of physicsJilin UniversityChangchun 130000China Changchun Institute of Technology Changchun 130012China

Columbite Zn0.8Co0.2Nb2O6 crystals were grown by optical floating zone methods. The x-ray diffraction(XRD) was used to check the structure information of the grown Zn0.8Co0.2Nb2O6 crystal. The room temperature and temperature-dependent Raman spectra were tested to investigate the optical phonon behaviors of columbite Zn0.8Co0.2Nb2O6, which exhibited a temperature stable property. The magnetics properties of Zn0.8Co0.2Nb2O6, measured by a physical property measurement system(PPMS), were also presented in this work.

关键词： columbite Zn0.8Co0.2Nb2O6 optical floating zone methods Raman spectra magnetics properties

Abnormal Elastic Changes for Cubic-Tetragonal Transition of Single-Crystal SrTiO_(3)

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Chinese Physics Letters 2022年第9期39卷 33-40页

作者： Caizi Zhang fangfei li Xinmiao Wei Mengqi Guo Yingzhan Wei liang li Xinyang li Qiang Zhou State Key Laboratory of Superhard Materials Jilin UniversityChangchun 130012China Synergetic Extreme Condition User Facility Jilin UniversityChangchun 130012China

Strontium titanate(SrTiO_(3))is a typical perovskite-type ceramic oxide and studying its high-pressure phases are critical to understand the ferroelastic phase ***_(3)also can be used as an important analog of davemaoite(CaSiO_(3))to understand the compositional and velocity structure of the Earth’s ***,the high-pressure studies on the cubic-to-tetragonal phase transition pressure and elastic properties remain unclear for SrTiO_(3).Here,we investigate the phase transition and elasticity of single-crystal SrTiO_(3)by Raman and Brillouin scattering combined with diamond anvil *** acoustic velocities of single-crystal SrTiO_(3)and the independent elastic constants of cubic and tetragonal SrTiO_(3)are determined up to 27.5 GPa at room *** study indicates that C_(11),C_(12),and C_(44)exhibit abnormal changes at 10.3 GPa,which is related to the cubicto-tetragonal phase ***,a significant softening on shear modulus and a large anisotropy of shear wave splitting(A_(S)^(PO))jump are observed at 10.3 *** obtained elastic constants,the coefficients of the Landau potential are calculated to understand the phase transition between cubic and *** calculated coefficients of the Landau potential are,λ_(2)=3.12×10^(-2)GPa,λ_(4)=-2.02×10^(-2)GPa,B~*=1.34×10^(-4)GPa and B=1.66×10^(-4)*** elastic results have profound implications in understanding the structure of the Earth’s interior and indicate that the presence of tetragonal Ti-bearing CaSiO_(3)helps to explain the large APO S of the Earth’s mid-mantle.

关键词： softening cubic tetragonal

Unveiling a Novel Insulator-to-Metal Transition in La_(N)iO_(4+δ):Challenging High-Temperature Superconductivity Claimed for Single-Layer Lanthanum Nickelates

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Chinese Physics Letters 2024年第9期41卷 93-106页

作者： Yunqi Ji Xiaohan Wang Xiaohe li Wenting Tang Xinyang li Xin Wang fangfei li liang li Qiang Zhou Synergetic Extreme Condition User Facility State Key Laboratory of Superhard MaterialsCollege of PhysicsJilin UniversityChangchun 130012China

La_(2)NiO_(4)has a similar structure to La_(2)CuO_(4)and was proposed as a high-temperature superconductor based on magnetic-moment measurements decades ***,with the exception for electrical resistance drop behavior of about 4 orders of magnitude that is claimed to originate from the superconductivity ever observed in Sr-doped La_(N)iO_(4),most electrical data reported to date in La_(N)iO_(4)system exhibit a trivial insulating ground ***,we definitively identify the similar electrical resistance drop behavior of more than 3 orders of magnitude in La_(2)NiO_(4+δ).However,our extensive investigations reveal that this phenomenon is a novel insulatorto-metal transition,distinct from ***,compared to the weak magnetic-field effects,pressure can significantly suppress the transition and transform from the metallic to an insulating ground state,accompanied by an isostructural phase *** work not only elucidates the fundamental properties of the metallic conducting ground state in La_(N)iO_(4)+δ,but also critically challenges the notion of superconductivity in single-layer lanthanum nickelates.

关键词： resistance electrical metallic

High-pressure synergetic measurement station(HP-SymS)

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Chinese Physics B 2018年第7期27卷 8-19页

作者： Xiaohui Yu fangfei li Yonghao Han Fang Hong Changqing Jin Zhi He Qiang Zhou Beijing National Laboratory for Condensed Matter Physics Institute of PhysicsChinese Academy of SciencesBeijing 100190China State Key Laboratory of Superhard Materials College of PhysicsJilin UniversityChangchun 130012China

In the High-Pressure Synergetic Measurements Station （HP-SymS） of the Synergic Extreme Condition User Facility （SECUF）, we will develop ultrahigh-pressure devices based on diamond-anvil cell （DAC） techniques, with a target pressure up to 300 GPa. With the use of cryostat and magnet, we will reach 300 GPa4.2 K-9 T and conduct simultaneous measurements of the electrical-transport property and Raman/Brillouin spectrascopy. With resistance heating and laser heating, we will reach temperatures of at least 1000 and 3000 K, respectively, coupled with Raman/Brillouin spectroscopy measurements. Some designs of supporting devices, such as a femtosecond laser gasket-drilling device, electrode-deposition device, and the gas-loading device, are also introduced in this article. Finally, we conclude by providing some perspectives on the applications of the DAC in related research fields.

关键词： high pressure synergetic measurements diamond-anvil cell (DAC)

The toxic natural product tutin causes epileptic seizures in mice by activating calcineurin

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Signal Transduction and Targeted Therapy 2023年第4期8卷 1916-1925页

作者： Qing-Tong Han Wan-Qi Yang Caixia Zang linchao Zhou Chong-Jing Zhang Xiuqi Bao Jie Cai fangfei li Qinyan Shi Xiao-liang Wang Jing Qu Dan Zhang Shi-Shan Yu State Key Laboratory of Bioactive Substances and Functions of Natural Medicines Institute of Materia MedicaPeking Union Medical College and Chinese Academy of Medical SciencesBeijing 100050China

Tutin,an established toxic natural product that causes epilepsy in rodents,is often used as a tool to develop animal model of acute epileptic ***,the molecular target and toxic mechanism of tutin were *** this study,for the first time,we conducted experiments to clarify the targets in tutin-induced epilepsy using thermal proteome *** studies showed that calcineurin(CN)was a target of tutin,and that tutin activated CN,leading to *** site studies further established that tutin bound within the active site of CN catalytic *** inhibitor and calcineurin A(CNA)knockdown experiments in vivo proved that tutin induced epilepsy by activating CN,and produced obvious nerve ***,these findings revealed that tutin caused epileptic seizures by activating ***,further mechanism studies found that N-methyl-D-aspartate(NMDA)receptors,gammaaminobutyric acid(GABA)receptors and voltage-and Ca2+-activated K+(BK)channels might be involved in related signaling *** study fully explains the convulsive mechanism of tutin,which provides new ideas for epilepsy treatment and drug development.

关键词： epilepsy seizures epileptic