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A Survey on 3D Visual Tracking of Multicopters

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International Journal of Automation and computing 2019年第6期16卷 707-719页

作者： Qiang Fu xiang-yang Chen Wei He School of Automation and Electrical Engineering University of Science and Technology BeijingBeijing 100083China Institute of Artificial Intelligence University of Science and Technology BeijingBeijing 100083China

Three-dimensional(3 D) visual tracking of a multicopter(where the camera is fixed while the multicopter is moving) means continuously recovering the six-degree-of-freedom pose of the multicopter relative to the camera. It can be used in many applications,such as precision terminal guidance and control algorithm validation for multicopters. However, it is difficult for many researchers to build a 3 D visual tracking system for multicopters(VTSMs) by using cheap and off-the-shelf cameras. This paper firstly gives an overview of the three key technologies of a 3 D VTSMs: multi-camera placement, multi-camera calibration and pose estimation for multicopters. Then, some representative 3 D visual tracking systems for multicopters are introduced. Finally, the future development of the 3D VTSMs is analyzed and summarized.

关键词： Multicopter three-dimensional(3D)visual tracking camera placement camera calibration pose estimation

Symmetry properties of fluctuations in an actively driven rotor

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Chinese Physics B 2020年第6期29卷 25-29页

作者： He Li xiang yang Hepeng Zhang School of Physics and Astronomy and Institute of Natural Sciences Shanghai Jiao Tong UniversityShanghai 200240China Collaborative Innovation Center of Advanced Microstructures Nanjing 210023China

We investigate rotational dynamics of an actively driven rotor through experiments and numerical simulations. While probability density distributions of rotor angular velocity are strongly non-Gaussian, relative probabilities of observing rotation in opposite directions are shown to be linearly related to the angular velocity magnitude. We construct a stochastic model to describe transitions between different states from rotor angular velocity data and use the stochastic model to show that symmetry properties in probability density distributions are related to the detailed fluctuation relation(FR) of entropy productions.

关键词： Brownian motor active bath fluctuation relation active matter

Ionization Channels of the Molecular Ion H^(+)_(2) in Intense Laser Field

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Chinese Physics Letters 2013年第11期30卷 71-75页

作者： MIAO xiang-yang SHI Hao-Ting College of Physics and Information Engineering Shanxi Normal UniversityLinfen 041004

Ionization channels of the molecular ion H^(+)_(2) for various initial vibrational states in intense laser field(80 fs,800 nm,I=6.8×10^(13) W/cm^(2))are theoretically investigated by numerically solving the time-dependent Schrödinger *** results confirm that the channels largely depend on the selection of initial vibrational states by analyzing the variations of peak locations in the nuclear initial kinetic-energy-release ***,the selection of the ionization channels is sensitive to the wavelength of the laser *** addition,time-dependent competition between direct multi-photon ionization and charge-resonance-enhanced ionization are is discussed.

关键词： spectra ionization Ionization

Theoretical Exploration of the Isotopic Effect on Nuclear Dynamics in Coulomb Explosion

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Chinese Physics Letters 2013年第6期30卷 80-84页

作者： SHI Hao-Ting MIAO xiang-yang College of Physics and Information Engineering Shanxi Normal UniversityLinfen 041004

The isotopic effect on nuclear dynamics in Coulomb explosion for various initial vibrational states of H_(2)^(+) and HD+in intense laser(80 fs,800 nm,I=6.8×10^(13)W/cm^(2)) is theoretically investigated by numerically solving the time-dependent Schrodinger *** calculated results confirm that the effect we discussed by paying close attention to the comparative analysis of peak locations in the nuclear kinetic-energy-release spectra largely depends on the selection of the initial vibrational ***,it is the special isotope effect case about the vibrational state v=5 that has been studied in *** also discuss the time-dependent spectrum atυ=7,which can reveal the difference in nuclear wavepacket motion between H_(2)^(+) and HD+in the time region in which charge-resonance enhanced ionization takes place.

关键词： equation. vibrational intense

Effect of tongue clearance on hydraulic performance of double support vortex pump

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Defence Technology（防务技术） 2019年第4期15卷 645-654页

作者： xiang-yang Li Wan-qiang Chen Sheng-dun Zhao Pump Equipment Engineering Research Center of Shaanxi Province Xi'an Aeronautical University Xi'an 710077 China School of Mechanical Engineering Xi'an Jiaotong University Xi'an 710049 China

In order to study influence of tongue clearance on the hydraulic performance of double support vortex pump,three dimensional flow model with symmetric variable size tongue clearance was established by changing section parameter of tongue clearance,and applied to numerically simulate the steady inner flow in a vortex pump based on fixed working conditions and impeller through ANSYS *** numerical results show the influence of tongue channel with two sections(non-uniform and uniform sections)on flow field characteristics in vortex ***,the variation of tongue channel section changes the vortex structure distribution in circumferential flow *** the spiral forward vortex structure in the circumferential direction shifts to large radius side with increasing tongue ***,the circumferential velocity gradient and axial pressure gradient both diminish with the increase of the tongue section,and the inlet/outlet pressure difference and velocity distribution also reduce with increasing tongue channel ***,for vortex pump with non-uniform section of tongue channel,the head diminishes and the efficiency remains constant approximately with the increase of the tongue width,while the head and the efficiency both diminish for uniform section of tongue channel.

关键词： Vortex pump Tongue clearance Non-uniform flow passage Numerical simulation

Bioinformatic identification of microRNAs and their target genes from Solanum tuberosum expressed sequence tags

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Chinese Science Bulletin 2007年第17期52卷 2380-2389页

作者： GUO Qiang xiang AnLina yang Qina yang ZhiMin Department of Biochemistry and Molecular Biology College of Life Sciences Nanjing Agricultural University Nanjing 210095 China

MicroRNAs (miRNAs) are a class of non-coding RNAs that regulate gene post-transcriptional expres- sion in plants and animals. Low levels of some miRNAs and time- and tissue-specific expression pat- terns lead to the difficulty for experimental identification of miRNAs. Here we present a bioinformatic approach for expressed sequence tags (ESTs) prediction of novel miRNAs as well as their targets in Solanum tuberosum. We blasted the databases of S. tuberosum ESTs to search for potential miRNAs, using previously known miRNA sequences from Arabidopsis, rice and other plant species. By analyzing parameters of plant precursors, including secondary structure, stem length and conservation of miRNAs, and following a variety of filtering criteria, a total of 22 potential miRNAs were detected. Using the newly identified miRNA sequences, we were able to further blast the S. tuberosum mRNA database and detected 75 potential targets of miRNAs in S. tuberosum. According to the mRNA annotations provided by the National Center for Biotechnology Information (NCBI) (http://***/), most of the miRNA target genes were predicted to encode transcription factors that regulate cell growth and development, signaling, and metabolism.

关键词：生物信息学茄子基因表达基因序列

Differentiation and immunosuppressive function of CD19^(+)CD24^(hi)CD27^(+) regulatory B cells are regulated through the miR-29a-3p/NFAT5 pathway

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Hepatobiliary & Pancreatic Diseases International 2024年第5期23卷 472-480页

作者： Jin-yang Li Tian-Shuo Feng Ji Gao Xin-xiang yang xiang-Cheng Li Zhen-Hua Deng Yong-xiang Xia Zheng-Shan Wu Hepatobiliary Center the First Affiliated Hospital of Nanjing Medical UniversityNanjing 210029China Key Laboratory of Liver Transplantation Chinese Academy of Medical SciencesNanjing 210029China NHC Key Laboratory of Living Donor Liver Transplantation Nanjing Medical UniversityNanjing 210029China

Background: Regulatory B cells(Bregs) is an indispensable element in inducing immune tolerance after liver transplantation. As one of the microRNAs(miRNAs), mi R-29a-3p also inhibits translation by degrading the target mRNA, and yet the relationship between Bregs and mi R-29a-3p has not yet been fully explored. This study aimed to investigate the impact of miR-29a-3p on the regulation of differentiation and immunosuppressive functions of memory Bregs(m Bregs) and ultimately provide potentially effective therapies in inducing immune tolerance after liver transplantation. Methods: Flow cytometry was employed to determine the levels of Bregs in peripheral blood mononuclear cells. TaqMan low-density array miRNA assays were used to identify the expression of different miRNAs, electroporation transfection was used to induce mi R-29a-3p overexpression and knockdown, and dual luciferase reporter assay was used to verify the target gene of miR-29a-3p. Results: In patients experiencing acute rejection after liver transplantation, the proportions and immunosuppressive function of m Bregs in the circulating blood were significantly impaired. mi R-29a-3p was found to be a regulator of m Bregs differentiation. Inhibition of miR-29a-3p, which targeted nuclear factor of activated T cells 5(NFAT5), resulted in a conspicuous boost in the differentiation and immunosuppressive function of m Bregs. The inhibition of mi R-29a-3p in CD19~+ B cells was capable of raising the expression levels of NFAT5, thereby promoting B cells to differentiate into m Bregs. In addition, the observed enhancement of differentiation and immunosuppressive function of m Bregs upon mi R-29a-3p inhibition was abolished by the knockdown of NFAT5 in B cells. Conclusions: mi R-29a-3p was found to be a crucial regulator for m Bregs differentiation and immunosuppressive function. Silencing mi R-29a-3p could be a potentially effective therapeutic strategy for inducing immune tolerance after liver transplantation.

关键词： Regulatory B cells miR-29a-3p NFAT5 Liver transplantation

Approximation for Ruin Probability in the Sparre Andersen Model with Interest

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Acta Mathematicae Applicatae Sinica 2006年第2期22卷 333-344页

作者： Ji-yang Tan xiang-qun yang Department of Mathematics Hunan Normal University Changsha 410081 China

We consider the Sparre Andersen model modified by the inclusion of interest on the surplus. Approximation for the ultimate ruin probability is derived by rounding. And upper bound and lower bound are also derived by rounding-down and rounding-up respectively. According to the upper bound and lower bound, we can easily obtain the error estimation of the approximation. Applications of the results to the compound Poisson model are given.

关键词： Sparre Andersen model compound Poisson model force of interest ruin probability

Site-Selective Magnetic Moment Collapse in Compressed Fe_(5)O_(6)

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Chinese Physics Letters 2021年第8期38卷 151-155页

作者： Qiao-Ying Qin Ai-Qin yang xiang-Ru Tao Liu-xiang yang Hui-yang Gou Peng Zhang MOE Key Laboratory for Nonequilibrium Synthesis and Modulation of Condensed Matter School of PhysicsXi’an Jiaotong UniversityXi’an 710049China Center for High Pressure Science and Technology Advanced Research Beijing 100094China

Iron oxide is one of the most important components in the Earth’s *** recent discovery of the stable presence of Fe_(5)O_(6) in the Earth’s mantle environment has stimulated significant interests in understanding of this new category of iron *** report the electronic structure and magnetic properties of Fe_(5)O_(6) calculated by the density functional theory plus dynamic mean field theory(DFT+DMFT)*** calculations indicate that Fe_(5)O_(6) is a conductor at ambient pressure with dominant Fe-3 d density of states at the Fermi *** magnetic moments of iron atoms at three non-equivalent crystallographic sites in Fe_(5)O_(6) collapse at significantly different rates under *** site-selective collapse of magnetic moments originates from the shifting of energy levels and the consequent charge transfer among the Fe-3 d orbis when Fe_(5)O_(6) is being *** simulations suggest that there could be high conductivity and volume contraction in Fe_(5)O_(6) at high pressure,which may induce anomalous features in seismic velocity,energy exchange,and mass distribution in the deep interior of the Earth.

关键词： theory magnetic