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Journal of Systems Engineering and Electronics 2020年第5期31卷 884-889页

作者： WANG Wantian TANG Ziyue chen yichang SUN Yongjian Department of Early Warning Technology Air Force Early Warning AcademyWuhan 430019China

This paper proposes a parity recognition of blade number and manoeuvre intention classification algorithm of rotor target based on the convolutional neural network(CNN) using micro Doppler features. Firstly, the time-frequency spectrograms are acquired from the radar echo by the short-time Fourier ***, based on the obtained spectrograms, a seven-layer CNN architecture is built to recognize the blade-number parity and classify the manoeuvre intention of the rotor target. The constructed architecture contains a leaky rectified linear unit and a dropout layer to accelerate the convergence of the architecture and avoid over-fitting. Finally, the spectrograms of the datasets are divided into three different ratios, i.e., 20%, 33% and 50%,and the cross validation is used to verify the effectiveness of the constructed CNN architecture. Simulation results show that, on the one hand, as the ratio of training data increases, the recognition accuracy of parity and manoeuvre intention is improved at the same signal-to-noise ratio(SNR);on the other hand, the proposed algorithm also has a strong robustness: the accuracy can still reach 90.72% with an SNR of – 6 dB.

关键词： micro-Doppler convolutional neural network(CNN) parity recognition of blade number manoeuvre intention classification

Hydrogen and Oxygen Isotope Study on the Water-Rock Interaction of the Yinshan (Cu-) Pb-Zn-Ag Ore Deposit, Jiangxi Province

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Acta Geologica Sinica(English Edition) 1996年第3期70卷 274-289页

作者： Zhang Ligang, Liu Jingxiu, Yu Guixiang and chen Zhensheng yichang Institute of Geology and Mineral Resources, CAGS, yichang, Hubei Jiang Minxi Y ichang Institute of Geology and Mineral Resources CAGS Yichang Hubei

The δ18O values of vein quartz of different stages from the Yinshan ore deposit are constant around 16‰ and the calculated δ18OH2O values attain 8‰± ; the δDH2O values of fluid inclu-sions in vein quartz are constant at about-60‰. From the surface down to 1200 m below the δ18O values of altered rocks gradually decrease from 15‰± to 11‰± . Various water-rock inversion calculations indicate that the ore fluids were formed by the interaction between meteoric water and phyllite at 350℃ and the effective W/ R value of around 0.1. When the water-rock exchange in the upper mineralization system took place, the effective W / R value increased to 5.0 or more. As a result, an evolution and mineralization model of a buffered open system with two-stage water-rock interactions is proposed in this study.

关键词： H and O isotopes water-rock exchange buffered open system Yinshan of Jiangxi Province

Vegetation Landscape,Ecological Characteristics and Soil Fixation for Riverbank in Taiwan,China

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Wuhan University Journal of Natural Sciences 2007年第4期12卷 677-683页

作者： CHANG Chunpin LIN Farching LIANG Taching chen yichang Department of Landscape Architecture Chung-Chou Institute of Technology Zhanghua 150 Taiwan China Department of Forestry and Resource Conservation Taiwan University Taipei 106 Taiwan China Department of Landscape Design and Management Chin Yi University of Technology Taichung 411 Taiwan China

This study is aimed to investigate and analyze the vegetation landscape around Rivers of Hou-lung, Fa-tz, Da-li, Ching-shuei and Gau- ping, and to select the suitable plant species that could be applied for the area of riverbank ecological engineering in Taiwan. Studying the vegetation established the key point and procedure of ecological engineering in the riverside and revetment, to compile and edit the dominant plants＇ types, life form, propagating method, root systems＇ characteristics and functions for soil conservation. This research choses three dominant plants for roots strength test. The fitting models of plants pulling resistance（Rp, kg） between plant height （H, cm）, diameter near ground （Dn, mm）, diameter above ground 100 mm （Da, mm）, The research finished the relative abundant, types and cluster analysis of riverbank dominant plants that generalize vegetative distribution and ecological restoration for different river types to apply and manage in Taiwan.

关键词： vegetation landscape ecological restoration dominant plants pulling resistance

Early Ordovician Sea Level Changes in South China and Their Worldwide Correlation

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Journal of Earth Science 1996年第1期15卷 54-62页

作者： Wang Xiaofeng (yichang Institute of Geology and Mineral Resources, CAGS, yichang 443003) Li Zhiming chen Jianqiang (Department of Geology and Mineral Resources, China University of Geosciences, Beijing 100083) chen Xiaohong (yichang Institute of Geology a

The sea level changes and their correlation from the latest Cambrian C. proavus zone to the Ordovician N. gracilis zone in South China are discussed on the basis of the Ordovician paleogeographic reconstruction in China. The study of sequence, biostratigraphy and ecostratigraphy suggests that at least 8 major regressive events, occurring in the following levels: basal H. simplex zone (RE1), near the base of C. intermedius zone (RE2), basal C. angulatus zone (RE3), near Mid/Upper G. quadriplicatus zone (RE4) and succeeding the first phase (RE4a) of RE4 at basal P. deltifer zone, Kiaerograptus/Brygograptus zonal boundary (RE5), end *** A. Z.(RE6), end P. originalis zone (RE7) and Early H. teretiusculus or end P. serra zone (RE8), can be recognized in the cratonic plat- form and its shelf-slope tracts of the South China plate based on sequence change or disconformity and associated breaks in biological succession. Most of them can be traced in the other plates or continents.

关键词： Ordovician sea level change sequence.

一种基于SAR稀疏采样数据的动目标运动参数估计方法

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电子与信息学报 2016年第12期38卷 3049-3055页

作者：陈一畅张群空军工程大学信息与导航学院西安710077 清华大学电子工程系北京100084 复旦大学电磁波信息科学教育部重点实验室上海200433

该文针对地面动目标运动参数估计问题进行研究,提出一种利用单天线合成孔径雷达(SAR)稀疏采样数据的动目标2维速度估计方法。首先以目标2维速度为参数构建一个等效参数化模型将动目标回波数据转化为小斜视回波数据,然后利用改进的迭代... 详细信息

该文针对地面动目标运动参数估计问题进行研究,提出一种利用单天线合成孔径雷达(SAR)稀疏采样数据的动目标2维速度估计方法。首先以目标2维速度为参数构建一个等效参数化模型将动目标回波数据转化为小斜视回波数据,然后利用改进的迭代阈值算法实现不同参数条件下的动目标2维成像,最后以成像结果的图像熵值为优化准则对初始模型参数进行搜索,从而获得准确的动目标运动参数。该方法以稀疏采样数据为输入,可以减少所需数据量,并且能够有效避免多普勒模糊问题,在较低信杂比条件下仍然能够准确估计出目标运动参数。仿真实验结果验证了所提动目标参数估计方法的有效性。

关键词：合成孔径雷达参数化模型运动目标参数估计

贵州关岭地区中晚三叠世法郎组中的软骨鱼类微体化石新材料

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微体古生物学报 2002年第3期19卷 276-287页

作者：陈立德宜昌地质矿产研究所宜昌443003

软骨鱼类的微体化石具有区域甚至全球性的地层对比潜力 ,还可以用于有机成熟度的分析。贵州关岭中晚三叠世法郎组产数量丰富、类型繁多的软骨鱼类微体化石 ,本文按照形态分类系统 ,对其进行了分类和描述。

关键词：贵州关岭地区中晚三叠世法郎组软骨鱼类微体化石新材料

基于稀疏FrFT的窄带雷达目标架次识别方法

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系统工程与电子技术 2021年第8期43卷 2129-2136页

作者：陈一畅熊鑫王万田空军预警学院湖北武汉430019 抚远雷达站黑龙江佳木斯156500

架次识别对于窄带雷达编队目标的探测与识别具有重要意义。本文基于最小熵准则提出了稀疏分数阶傅里叶变换(fractional Fourier transform,FrFT)最优变换阶次估计算法,首先将雷达回波数据的FrFT结果的熵值建模为变换阶次的函数,进而将... 详细信息

架次识别对于窄带雷达编队目标的探测与识别具有重要意义。本文基于最小熵准则提出了稀疏分数阶傅里叶变换(fractional Fourier transform,FrFT)最优变换阶次估计算法,首先将雷达回波数据的FrFT结果的熵值建模为变换阶次的函数,进而将变换阶次估计问题转化为稀疏优化问题,利用稀疏重构算法获得最优变换阶次。最后,应用该算法分析窄带雷达多波门回波数据Doppler频率特性,获取编队目标的架次信息。仿真和实测数据结果表明,所提方法避免了暴力搜索能够快速获得FrFT最优变换阶次,将该算法应用于窄带雷达回波信号处理能够准确识别编队目标架次信息。

关键词：分数阶傅里叶变换最小熵稀疏优化窄带雷达架次识别

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基于改进多重测量向量模型的SAR成像算法

电子与信息学报 2016年第10期38卷 2423-2429页

作者：陈一畅张群杨婷罗迎空军工程大学信息与导航学院复旦大学电磁波信息科学教育部重点实验室空军预警学院黄陂士官学校中国人民解放军95133部队

近年来,基于压缩感知(Compressed Sensing,CS)理论的稀疏场景SAR成像成为研究热点。在CS理论中,对于具有相同稀疏结构的联合稀疏目标信号源,多重测量向量(Multiple Measurement Vectors,MMV)模型可以获得优于单重测量矢量(Single Measur... 详细信息

近年来,基于压缩感知(Compressed Sensing,CS)理论的稀疏场景SAR成像成为研究热点。在CS理论中,对于具有相同稀疏结构的联合稀疏目标信号源,多重测量向量(Multiple Measurement Vectors,MMV)模型可以获得优于单重测量矢量(Single Measurement Vector,SMV)模型的重构性能。然而,在距离徙动(Range Migration)不可忽略的应用场景,SAR各脉冲回波1维距离像具有不完全相同的稀疏结构,这使得无法在SAR应用中直接引入MMV模型。该文针对MMV模型与SAR距离徙动的矛盾,提出一种改进的MMV模型。在该模型下,各方位向位置对应的1维距离像的稀疏结构不要求完全相同,而是符合距离徙动特性。论文所提出的RM-OMP算法根据符合距离徙动特性的稀疏结构搜索稀疏信号支撑集,可以准确地重建稀疏信号源。论文采用仿真数据和实测数据实验验证了所提模型和算法的有效性。

关键词：合成孔径雷达稀疏恢复多重测量向量模型距离徙动

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长江三峡东部早奥陶世早期的几丁虫

微体古生物学报 1992年第3期9卷 283-290,341页

作者：汪啸风陈孝红中国地质科学院宜昌地质矿产研究所宜昌443003

该文介绍了国内外关于早奥陶世早期的几丁虫研究现状,描述了峡东地区早奥陶世早期分乡组的几丁虫3属6种:Conochitina symmetrica,Conochitina ***,Conochitina sp.A,Conochitina sp.B,Lagenochitina ***,Cyathochitina sp.。根据共生的笔石和牙形石以及这些几丁虫在世界其它地区的地质分布,讨论了其时代与对比问题。指出了长江三峡东部早奥陶世早期的几丁虫面貌与世界各地同期几丁虫生物古地理的亲缘关系。

关键词：几丁虫早奥陶世长江三峡

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基于CEMD的旋翼微动目标杂波抑制方法

航空学报 2018年第9期39卷 179-188页

作者：夏赛强向虎陈文峰杨军陈一畅空军预警学院武汉430019

针对旋翼微动目标杂波抑制问题,研究了一种基于复数据经验模态分解(CEMD)的微动目标杂波抑制方法。首先,建立了地杂波背景下的旋翼微动目标信号模。然后,根据杂波和微动信号在时频域的差异性,基于CEMD和Gabor变换,通过新定义的不同本征... 详细信息

针对旋翼微动目标杂波抑制问题,研究了一种基于复数据经验模态分解(CEMD)的微动目标杂波抑制方法。首先,建立了地杂波背景下的旋翼微动目标信号模。然后,根据杂波和微动信号在时频域的差异性,基于CEMD和Gabor变换,通过新定义的不同本征模态函数(IMF)的能量所占总能量的比重,选择出微动信号占优所对应的几个IMF分量,并基于这些IMF对旋翼微动目标进行时域和时频域重构,实现旋翼微动目标和杂波的分离,达到抑制杂波提取微动目标回波的目的。最后,与常规杂波抑制方法进行了对比,仿真结果验证了所提方法的有效性。

关键词：微动杂波抑制 Gabor变换复数据经验模态分解(CEMD) 本征模态函数(IMF)