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Imaging and structural feature decomposition of a complex target using multi-aspect polarimetric scattering

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Science China(Information Sciences) 2016年第8期59卷 220-233页

作者： Yongchen li Ya-Qiu jin Key Laboratory for Information Science of Electromagnetic Waves Fudan University

Based on the Huynen parametric decomposition of target scattering matrix, the polarimetric ellipse parameters are transformed and applied to decomposition of scattering mechanisms of a complex target in VHR POL-SAR images(very high resolution, polarimetric synthetic aperture radar). Making use of multi-aspect(or circle-aspect) and wideband VHR POL-SAR images, scattering mechanisms of a volumetric target and its structural components are recognized over image pixels. Utilizing the layover features, the target height profile is also estimated from two-dimensional image. As example, polarimetric scattering data of some vehicles on ground, including multi-aspect simulated data and experimental measurements, are applied to validations of scattering mechanism decompositions and target structural feature recognition.

关键词： scattering mechanism polarimetric decomposition multi-aspect imaging target recognition

Kantorovich’s theorem for Newton’s method on lie groups

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Journal of Zhejiang University-Science A(Applied Physics & Engineering) 2007年第6期8卷 978-986页

作者： WANG jin-hua li Chong Department of Mathematics Zhejiang University of Technology Hangzhou 310032 China Department of Mathematics Zhejiang University Hangzhou 310027 China

The convergence criterion of Newton’s method to find the zeros of a map f from a lie group to its corresponding lie algebra is established under the assumption that f satisfies the classical lipschitz condition, and that the radius of convergence ball is also obtained. Furthermore, the radii of the uniqueness balls of the zeros of f are estimated. Owren and Welfert (2000) stated that if the initial point is close sufficiently to a zero of f, then Newton’s method on lie group converges to the zero; while this paper provides a Kantorovich’s criterion for the convergence of Newton’s method, not requiring the existence of a zero as a priori.

关键词： Newton's method lie group Kantorovich's theorem lipschitz condition

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Interaction Mechanism of Nano-silicon Dioxide Modified by Poly（amidoamine） Dendrimers

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Chinese Journal of Chemical Physics 2012年第5期25卷 592-604,I0004页

作者： Tao jin Xiao-yu li College of Material Science and Engineering Shandong University of Science and TechnologyQingdao 265590China College of Material Science and Engineering Beijing University of Chemical TechnologyBeifing100020China

To gain insight into the attachment of =Si^＋（SC） ion （regarded as guest） to the lowest generation, NH2-terminated poly（amidoamine）（PAMAM） dendrimers （regarded as host） in the liquid phase, density functional theory is used to investigate the structures and energetics of the host-guest complex. The effect of solvent on the structures and energetics is also investigated. Various initial configurations of the ion bound to PAMAM are tested, and two stable conformers are found, i.e, types A （=Si^＋ is bound to the amine site） and C （=Si^＋ is bound to the amide site）. Types A and C are the most stable due to the chemical bond formations of Si-N° （amine nitrogen atoms） and Si-O, respectively. The IR spectra for the lowest energy conformers are thoroughly analyzed and compared with the available experimental data.

关键词： Poly(amidoamine) Nano-silicon dioxide Configuration Density functionaltheory

Effects of physical properties of supercritical water on coarse graining of particle cluster

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Particuology 2023年第11期82卷 166-178页

作者： Xiaoyu li Huibo Wang Yi li Hui jin State Key Laboratory of Multiphase Flow in Power Engineering Xi'an Jiaotong UniversityXi'an710049China

The coarse graining of particle cluster is of great significance to the study of a fluidized bed. The effects of variations in the physical properties of supercritical water on the coarse graining of particle cluster are investigated in this work. The drag coefficient distributions of the particle cluster are not influenced by the physical properties. However, the physical properties have effects on the values of drag coefficient. The effects of physical properties are weaker in the case of large particle concentrations. Furthermore, the physical properties lead to that the effect of particle cluster wake on the drag of downstream particles being significantly different from that of constant property flow. The variation trend of drag of coarse graining particle is consistent with that of isolated particle. The physical properties lead to significant differences in the values of drag. In this paper, the dominance of the effects of physical properties in a variety of cases is confirmed. Finally, a physical properties effect model is developed accordingly.

关键词： Supercritical water Variations in physical properties Fluidized bed Coarse grain method Particle drag

Target decomposition and recognition from wide-angle SAR imaging based on a Gaussian amplitude-phase model

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Science China(Information Sciences) 2017年第6期60卷 212-224页

作者： Yongchen li Ya-Qiu jin Key Laboratory for Information Science of Electromagnetic Waves Fudan University

Wide-angle synthetic aperture radar(W-SAR) imaging accounts for multi-azimuthal scattering and is feasible for retrieving more comprehensive features of complex targets. Because a typical target is seen as composed of its components(typically, some simple geometric objects), a Gaussian amplitude-phase(GAP)model has been developed for the analysis of multi-azimuthal scattering from these objects. Based on the timefrequency analysis of wide-angle scattering, the parameters of the GAP model were estimated, including the Gaussian variance, the surface curvature, and the number of objects in all imaged pixels. Numerical simulations and real measurements demonstrate the capability of the GAP model for decomposing and recognizing complex electric-large targets.

关键词： wide-angle SAR Gaussian amplitude-phase time-frequency target decomposition target recognition

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新时代高校思政课教师基本素养的提升

四川文理学院学报 2025年第1期35卷 122-128页

作者：李津温国艳海南师范大学马克思主义学院海南海口571158 海南师范大学附属小学海南海口571158

高校思政课教师承担着立德树人、铸魂育人的神圣使命。提升新时代高校思政课教师基本素养是适应社会环境变化、推进高校思政课改革创新和促进高校思政课教师履行职责的需要。当前党和国家对思政课教师基本素养的要求和高校思政课教师基... 详细信息

高校思政课教师承担着立德树人、铸魂育人的神圣使命。提升新时代高校思政课教师基本素养是适应社会环境变化、推进高校思政课改革创新和促进高校思政课教师履行职责的需要。当前党和国家对思政课教师基本素养的要求和高校思政课教师基本素养的现实情况之间存在着一定差距。要通过加强顶层设计和制度建设,增强外部动力和深化高校思政课教师基本素养的培育,激发其内在潜能,以全方位强化思政课教师基本素养的提升。

关键词：高校思政课教师基本素养

A double-edged sword of immuno-microenvironment in cardiac homeostasis and injury repair

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Signal Transduction and Targeted Therapy 2021年第3期6卷 779-794页

作者： Kang Sun Yi-yuan li jin jin MOE Laboratory of Biosystem Homeostasis and Protection and Life Sciences InstituteZhejiang UniversityHangzhou 310058China Key Laboratory for Developmental Genes and Human Disease Ministry of EducationInstitute of Life SciencesJiangsu Province High-Tech Key Laboratory for Bio-Medical ResearchSoutheast UniversityNanjing 210096China Sir Run Run Shaw Hospital College of Medicine Zhejiang UniversityHangzhou 310016China

The response of immune cells in cardiac injury is divided into three continuous phases:inflammation,proliferation and *** kinetics of the inflammatory and proliferation phases directly influence the tissue *** cardiac homeostasis,cardiac tissue resident macrophages(cTMs)phagocytose bacteria and apoptotic ***,NK cells prevent the maturation and transport of inflammatory *** cardiac injury,cTMs phagocytose the dead cardiomyocytes(CMs),regulate the proliferation and angiogenesis of cardiac progenitor *** cells prevent the cardiac fibrosis,and promote vascularization and *** 1 macrophages trigger the cardioprotective responses and promote tissue fibrosis in the early ***,type 2 macrophages promote cardiac remodeling and angiogenesis in the late *** macrophages and neutrophils firstly lead to chronic inflammation by secreting proinflammatory cytokines,and then release anti-inflammatory cytokines and growth factors,which regulate cardiac *** this process,dendritic cells(DCs)mediate the regulation of monocyte and macrophage *** eosinophils and Mast cells(MCs)release some mediators which contribute to coronary vasoconstriction,leukocyte recruitment,formation of new blood vessels,scar *** adaptive immunity,effector T cells,especially Th17 cells,lead to the pathogenesis of cardiac fibrosis,including the distal fibrosis and scar *** protectors,Treg cells,inhibit reduce the inflammatory response,then directly trigger the regeneration of local progenitor cell via IL-10.B cells reduce myocardial injury by preserving cardiac function during the resolution of inflammation.

关键词： cardiac homeostasis inflammation

Priority effects of forbs arriving early:the role of root interaction and asymmetric competition

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Ecological Processes 2024年第1期13卷 53-65页

作者： Xiaohong Yan Xiliang li Ke jin Institute of Grassland Research Chinese Academy of Agricultural Sciences

Background The priority effect of plant arrival is a key driver of community assembly and ecosystem succession during the restoration of degraded plant communities. However, the significance of the arrival order of different plant functional groups and their interactions with community assemblies remains unclear. Using a phytotron experiment with three fully crossed factors, we investigated the underlying mechanisms of priority effects and their relationships with the biomass and biodiversity effects in mixed plant communities by manipulating the order of arrival of species, isolation of roots, and removal of specific *** The results showed that the strength and direction of priority effects were influenced by arrival order, root interactions, asymmetric competition among species, and their interactions. The identities of early and late-sown species also determined the magnitude of priority effects. The priority effects were stronger in grass-first(24.76%) and legume-first communities(24.48%) than in forb-first communities. The pot biomass of the different priority treatments was highest in grass-first(5.85 g), followed by legume-first(3.94 g) and forb-first(2.48 g). The order of arrival in the mixture significantly affected the net biodiversity effects(P lies. In addition, the importance of the priority effect of forbs sown first is related to community assembly, which may be a key determinant in successfully establishing a highly diverse community in the early stages of restoration. Species with weak competition should be considered in the early stage of community ass

关键词： Community assembly Order of arrival Overyielding Plant functional group Root isolation

Improvements in properties of NdFeB magnets obtained via magnetron sputtering and thermal diffusion

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Journal of Rare Earths 2024年第9期42卷 1710-1716,I0003页

作者： jin Tang Weichao Huang Dan li School of Electronic Engineering Guangxi University of Science and TechnologyLiuzhou545006China China Rare Earth(Guangxi)jinyuan Rare Earth New Materials Co. Ltd.Hezhou542603China China Rare Earth Group Co. Ltd.Ganzhou341000China Center of Experimental Teaching for Common Courses Panzhihua UniversityPanzhihua617000China

The grain boundary diffusion process(GBDP) of Dy and DyAl on sintered NdFeB magnets was conducted via magnetron-sputtering deposition of Dy and DyAl films to enhance coercivity(H_(cj)),The magnetic properties,microstructure and anti-corrosion properties of Dy-surface-alloying NdFeB magnets obtained via magnetron sputtering and thermal diffusion were *** H_(cj) of the Dy_(95)Al_(5)-NdFeB magnet increases by 32.68%,while the remanence declines ***,X-ray diffraction and microstructural analysis confirm the formation of Dy-rich shells,the higher-magnetic-anisotropy field of hard(Nd_(x)Dy_(1-x))2(FeAl)_(14)B magnetic phases and an optimised grain boundary structu re,contributing to the H_(cj)enhancement of the *** elemental distribution and diffusion mechanism of the magnets are also ***,the corrosion resistance of the Dy_(95)Al_(5)-NdFeB magnet is substantially improved by enhancing the electrochemical stability and optimising the distribution and morphology of the intergranular *** findings of this study are of substantial importance in the development of low-heavy rare-earth sintered NdFeB magnets.

关键词： Magnetron sputtering NdFeB Rare earths Microstructure Magnetic property Corrosion resistance

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