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基于非质点模型的纯方位解距离方法

计算机与数字工程 2013年第7期41卷 1070-1073页

作者：石杰戚国庆盛安冬南京理工大学自动化学院南京210094

目标距离是战场进行作战决策和武器使用时考虑的一个重要参数。在传统的二维被动跟踪系统基础上,将目标建模为椭圆刚体。论文借鉴修正极坐标(MPC)的思想,利用刚体目标的尺寸参数,建立目标的状态模型和测量模型。采用无迹卡尔曼滤波(UKF... 详细信息

目标距离是战场进行作战决策和武器使用时考虑的一个重要参数。在传统的二维被动跟踪系统基础上,将目标建模为椭圆刚体。论文借鉴修正极坐标(MPC)的思想,利用刚体目标的尺寸参数,建立目标的状态模型和测量模型。采用无迹卡尔曼滤波(UKF)算法进行解距离,为工程实现提供了可能性,并从不同的初始条件下分析了距离误差。Monte-Carlo仿真表明:在新的状态模型下利用UKF算法进行解距离,可以达到较高的精度。其中传感器与目标的相对速度和刚体目标的尺寸对距离解的精度影响较大。

关键词：非质点纯方位非线性滤波器解距离

Cramer-Rao Lower Bounds for Bearings-Only Maneuvering Target Tracking with Incomplete Measurements

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Cramer-Rao Lower Bounds for Bearings-Only Maneuvering Target...

Boosting Oxygen Evolution Reaction Performance on NiFe‑Based Catalysts Through d‑Orbital Hybridization

2009中国控制与决策会议

作者： Xu Zhigang~(1,2),sheng andong~1,Li Yinya~1 1.School of Automation,Nanjing University of Science and Technology,Nanjing 210094,China 2.School of Sciences,Huaihai Institute of Technology,Lianyungang 222005,China

The theoretical Cramer-Rao lower bound(CRLB) for bearings-only maneuvering target tracking is derived in the case where the observation measurements are lost in a random *** binary variables are introduced to model two events respectively,one which the target maneuvers or not and another that the target is detected or *** corresponding recursive formula for theoretical CRLB is then derived based on the sequential version of the CRLB for general nonlinear *** theoretical formula suffers from heavy calculation load of the Fisher information matrix (FIM) while the constant probability of detection is less than *** approximation of the theoretical bound is proposed. In addition,a detection reduction factor bound is presented and proved to be less than the theoretical *** results are illustrated with a numerical example.

关键词： Cramer-Rao lower bound Maneuvering target tracking Incomplete measurements Bearings-only tracking

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Nano-Micro Letters 2025年第1期17卷 281-292页

作者： Xing Wang Wei Pi sheng Hu Haifeng Bao Na Yao Wei Luo State Key Laboratory of New Textile Materials and Advanced Processing Technology Key Laboratory of New Textile Materials and Applications of Hubei ProvinceSchool of Materials Science and EngineeringWuhan Textile UniversityWuhan 430200People’s Republic of China College of Chemistry and Molecular Sciences Wuhan UniversityWuhan 430072People’s Republic of China

Anion-exchange membrane water electrolyzers(AEMWEs)for green hydrogen production have received intensive attention due to their feasibility of using earth-abundant NiFe-based *** introducing a third metal into NiFe-based catalysts to construct asymmetrical M-NiFe units,the d-orbital and electronic structures can be adjusted,which is an important strategy to achieve sufficient oxygen evolution reaction(OER)performance in ***,the ternary NiFeM(M:La,Mo)catalysts featured with distinct M-NiFe units and varying d-orbitals are reported in this *** and theoretical calculation results reveal that the doping of La leads to optimized hybridization between d orbital in NiFeM and 2p in oxygen,resulting in enhanced adsorption strength of oxygen intermediates,and reduced rate-determining step energy barrier,which is responsible for the enhanced OER *** critically,the obtained NiFeLa catalyst only requires 1.58 V to reach 1 A cm^(−2) in an anion exchange membrane electrolyzer and demonstrates excellent long-term stability of up to 600 h.

关键词： NiFe-based catalysts d-orbital coupling Oxygen evolution reaction Anion exchange membrane electrolyzer

The Study on Satisfactory Bias-allowable Estimator of Discrete System

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The Study on Satisfactory Bias-allowable Estimator of Discre...

Constraints on what controls millennial-scale basin-wide denudation across mountain belts, Asia

2009中国控制与决策会议

作者： Teng Kenan~(1,2),Qi Guoqing~2,sheng andong~2 1.Scientific Researching Department,Yantai Naval Aeronautical Engineering Institute,Yantai 264001 2.Automatic School,Nanjing University of Science & Technology,Nanjing 210094

＜正＞Aiming at the target tracking problem in fire control system,the satisfactory discrete-time bias-allowable estimator is investigated in this *** fire control system,the smoothness of forecasting target future positions is an important factor that affects shooting *** lower order system model to estimate target state is a common method of smoothly forecasting the future position,which could produce system bias when the target is suddenly *** important index in constraining system error called steady error coefficient is introduced into the performance index set with error variance upper bound and area pole *** the maneuvering intensity of target is finite,an iterative algorithm in terms of linear matrix inequalities（LMIs） is proposed to solve the satisfactory bias-allowable estimation *** proposed bias-allowable estimator can ensure the accuracy and smoothness of the estimation output by using a lower order system *** an example is presented to demonstrate the obtained results.

关键词： Target Tracking Bias-allowable Estimation Linear Matrix Inqeuality Steady Error Coefficient Multi Indices Constraint

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Science China Earth Sciences 2025年第1期68卷 74-93页

作者： Ye YANG Steven A.BINNIE sheng XU Cong-Qiang LIU Tibor J.DUNAI Institute of Surface-Earth System Science School of Earth System Science Tianjin University Institute of Geology and Mineralogy University of Cologne

The terrestrial cosmogenic nuclide dataset consisting of 123310Be measurements of fluvial sediment samples across the Asian mountain belts is used to constrain the influence of climate,tectonics and topography on Earth-surface denudation processes.10Be-derived basin-wide denudation rates were recalculated using a Monte Carlo simulation approach that relied on pixel-by-pixel production *** rates derived span four orders of magnitude,from 7.4±0.7 mm kyr-1（1σ;Central Tibetan Plateau） to 9,646744+777mm kyr-1（1σ;Southern Tibetan Plateau）,with a median of 186 mm *** our results with the traditional basin-wide production rate scaling model using a centroid coordinate and mean elevation,suggests that 96.6%of production rates will be underestimated using the latter method,especially for basins with a large *** bias between both methods reaches as large as 40%,caused by basin hypsometry and the nonlinear scaling of production rate with elevation and *** of the correlations between uniformly recalculated denudation rates and tectonics,climate,topography and rock lithology will facilitate the extrapolation of denudation rates in unknown basins using available *** the perspective of local scales,precipitation coupled with neotectonics-driven landslides is likely the most influential factor in subtropical Taiwan Island,while topography primarily constrains surface denudation rates in the eastern Tibetan Plateau within a narrow range of *** highland regions with glacier coverage,such as the Pamir,central and southern Tibetan Plateau high denudation rates are affected by glaciation,whereas lower precipitation and high erosion base level may limit river incision and evolving relief in the Central Tibetan *** contrast to local-scale findings highlighting a dominant factor constraining denudation rate,our large-scale quantitative analyses across the Asian mountain belts finds that （1） topographic metrics including

关键词： 10Be-derived denudation rate Climate change Tectonic uplift Topographic gradient Asian mountains

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基于压缩传感的多尺度传感器融合

计算机与数字工程 2013年第5期41卷 726-728,745页

作者：陈素娟戚国庆盛安冬南京理工大学自动化系南京210094

针对传统采样理论需要采集大量观测数据所带来的存储、传输以及经济方面的压力,提出了一种基于压缩传感理论的多尺度传感器融合方法。分析了基于压缩传感理论的重构算法的设计问题,采用曲线拟合方法对多尺度的传感器的时间配准。仿真结... 详细信息

针对传统采样理论需要采集大量观测数据所带来的存储、传输以及经济方面的压力,提出了一种基于压缩传感理论的多尺度传感器融合方法。分析了基于压缩传感理论的重构算法的设计问题,采用曲线拟合方法对多尺度的传感器的时间配准。仿真结果表明,基于正交匹配追踪算法几乎可以完全重构原始信号。与传统采样算法相比,虽然精度没有传统的方法高,但是在误差允许范围内,采集的数据少,所需时间少,减少了数据的传输和存储成本。

关键词：压缩传感重构算法曲线拟合多尺度传感器

Subretinal fibrosis secondary to neovascular age-related macular degeneration:mechanisms and potential therapeutic targets

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Neural Regeneration Research 2025年第2期20卷 378-393页

作者： Jingxiang Zhang Xia sheng Quanju Ding Yujun Wang Jiwei Zhao Jingfa Zhang Department of Ophthalmology People’s Hospital of Huangdao DistrictQingdaoShandong ProvinceChina Department of Urology People’s Hospital of Huangdao DistrictQingdaoShandong ProvinceChina Department of Ophthalmology Shanghai General Hospital(Shanghai First People’s Hospital)Shanghai Jiao Tong University School of MedicineShanghaiChina National Clinical Research Center for Eye Diseases Shanghai Key Laboratory of Ocular Fundus DiseasesShanghai Engineering Center for Visual Science and PhotomedicineShanghai Engineering Center for Precise Diagnosis and Treatment of Eye DiseasesShanghaiChina

Subretinal fibrosis is the end-stage sequelae of neovascular age-related macular *** causes local damage to photoreceptors,retinal pigment epithelium,and choroidal vessels,which leads to permanent central vision loss of patients with neovascular age-related macular *** pathogenesis of subretinal fibrosis is complex,and the underlying mechanisms are largely ***,there are no effective treatment options.A thorough understanding of the pathogenesis of subretinal fibrosis and its related mechanisms is important to elucidate its complications and explore potential *** current article reviews several aspects of subretinal fibrosis,including the current understanding on the relationship between neovascular age-related macular degeneration and subretinal fibrosis;multimodal imaging techniques for subretinal fibrosis;animal models for studying subretinal fibrosis;cellular and non-cellular constituents of subretinal fibrosis;pathophysiological mechanisms involved in subretinal fibrosis,such as aging,infiltration of macrophages,different sources of mesenchymal transition to myofibroblast,and activation of complement system and immune cells;and several key molecules and signaling pathways participating in the pathogenesis of subretinal fibrosis,such as vascular endothelial growth factor,connective tissue growth factor,fibroblast growth factor 2,platelet-derived growth factor and platelet-derived growth factor receptor-β,transforming growth factor-βsignaling pathway,Wnt signaling pathway,and the axis of heat shock protein 70-Toll-like receptors 2/*** review will improve the understanding of the pathogenesis of subretinal fibrosis,allow the discovery of molecular targets,and explore potential treatments for the management of subretinal fibrosis.

关键词： choroidal neovascularization epithelial-mesenchymal transition mesenchymal transition myofibroblast neovascular age-related macular degeneration submacular fibrosis subretinal fibrosis therapeutic targets transforming growth factor-β vascular endothelial growth factor

Vector meson's spin alignments in high energy reactions

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Science China(Physics,Mechanics & Astronomy) 2025年第1期Mechanics & Astronomy) .卷 5-20页

作者： Jin-Hui Chen Zuo-Tang Liang Yu-Gang Ma Xin-Li sheng Qun Wang Key Laboratory of Nuclear Physics and Ion-beam Application (MoE) Institute of Modern PhysicsFudan University Institute of Frontier and Interdisciplinary Science Key Laboratory of Particle Physics and Particle Irradiation (MOE)Shandong University INFN-Firenze Department of Modern Physics University of Science and Technology of China School of Mechanics and Physics Anhui University of Science and Technology

The global spin alignment of vector mesons has been observed by the STAR collaboration at the Relativistic Heavy Ion Collider （RHIC） at Brookhaven National Laboratory （BNL）.It provides a unique opportunity to probe the correlation between the polarized quark and antiquark in the strongly coupled quark-gluon plasma （sQGP） produced in relativistic heavy ion collisions,opening a new window to explore the properties of s *** addition,spin alignments of vector mesons have also been observed in other high-energy particle collisions such as e+e-annihilations at high energies where hadron production is dominated by quark fragmentation *** results obtained are quite different from those obtained in heavy ion collisions where quark coalescence/combination mechanism dominates suggesting strong dependence on hadronization *** comprehensive studies in different hadronization processes are *** this article,we present a brief review of theoretical and experimental advances in the study of vector meson’s spin alignments in a variety of high-energy particle collisions,with emphasis on hadronization mechanisms.

关键词： vector meson spin alignment global polarization relativistic heavy ion collisions fragmentation

Chiral phosphoramidite ligand-modulated palladium auto-tandem catalysis for asymmetric dehydrogenative dienylation of imines with α-alkenes

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Science China Chemistry 2025年

作者： Zhong-sheng Nong Hao-Fan Qian Ying-Chun Chen Pu-sheng Wang Liu-Zhu Gong Hefei National Research Center for Physical Sciences at the Microscale and Department of Chemistry University of Science and Technology of China Key Laboratory of Drug Targeting and Drug Delivery System (Sichuan University) Ministry of Education and Sichuan Research Center for Drug Precision Industrial Technology West China School of Pharmacy Sichuan University School of Materials and Chemistry Southwest University of Science and Technology

The development of efficient processes allowing rapid access to complex chiral molecules from easily available alkenes is a long-term pursuit in the synthetic chemistry community. Transition metal-catalyzed asymmetric functionalization of allylic C–H bond represents a unique alternative toward this goal. However, enantioselective dehydrogenative transformation of olefins to value-added optically enriched molecules remains yet to be discovered. Here, we report a highly enantioselective dehydrogenative dienylation of imines with unactivated α-alkenes driven by the synergistic action of palladium complex and carboxylic acid. Chiral phosphoramidite ligands turned out to be superior in modulating the performance of palladium autotandem catalysis and allowed a broad range of α-alkenes and imines to be transformed into chiral dienylamines. Mechanistic studies suggest that the dienes could be in situ generated from α-alkenes through a palladium(0)-mediated dehydrogenative process in the presence of excess benzoquinone oxidants, and then participated in the Pd-chiral phosphoramidite-catalyzed intermolecular vinylogous-type addition to the imines activated by the carboxylic acid co-catalyst. Notably, the second β-H elimination occurring in the dienylation event might be the turnover-limiting step.

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