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A Time-Frequency Associated MUSIC Algorithm Research on Human Target Detection by Through-Wall Radar

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Journal of Beijing Institute of Technology 2022年第1期31卷 123-130页

作者： Xianyu Dong Wu Ren Zhenghui Xue xuetian wang Weiming Li School of Integrated Circuits and Electronics Beijing Institute of TechnologyBeijing 100081China.

In this paper,a time-frequency associated multiple signal classification(MUSIC)al-gorithm which is suitable for through-wall detection is *** technology of detecting hu-man targets by through-wall radar can be used to monitor the status and the location information of human targets behind the ***,the detection is out of order when classical MUSIC al-gorithm is applied to estimate the direction of *** order to solve the problem,a time-fre-quency associated MUSIC algorithm suitable for through-wall detection and based on S-band stepped frequency continuous wave(SFCW)radar is *** associating inverse fast Fouri-er transform(IFFT)algorithm with MUSIC algorithm,the power enhancement of the target sig-nal is completed according to the distance calculation results in the time *** convert the signal to the frequency domain for direction of arrival(DOA)*** simulations of two-dimensional human target detection in free space and the processing of measured data are *** comparing the processing results of the two algorithms on the measured data,accuracy of DOA estimation of proposed algorithm is more than 75%,which is 50%higher than classical MUSIC *** is verified that the distance and angle of human target can be effectively de-tected via proposed algorithm.

关键词： through-wall radar multiple signal classification(MUSIC)algorithm inverse fast Four-ier transform(IFFT)algorithm target detection

Identification of Milankovitch Cycles and Calculation of Net Primary Productivity of Paleo-peatlands using Geophysical Logs of Coal Seams

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Acta Geologica Sinica(English Edition) 2022年第6期96卷 1830-1841页

作者： SHAO Longyi WEN He GAO Xiangyu Baruch SPIRO wang xuetian YAN Zhiming David J.LARGE College of Geoscience and Surveying Engineering China University of Mining and Technology(Beijing)Beijing 100083China Department of Earth Sciences Natural History MuseumLondon SW75BDUK Institute of Architectural Engineering Weifang UniversityWeifangShandong 261061China Faculty of Engineering University of NottinghamNottingham NG72RDUK

Individual coal seams formed in paleo-peatlands represent sustained periods of terrestrial carbon accumulation and a key environmental indicator attributed to this record is the rate of carbon *** the rate of carbon accumulation requires a measure of time contained within the *** study aimed to determine this rate via the identification of Milankovitch orbital cycles in the *** geophysical log is an ideal paleoclimate proxy and has been widely used in the study of sedimentary records using spectral *** analyses of geophysical log from thick coal seams can be used to identify the Milankovitch cycles and to calculate the period of the coal *** considering the carbon loss during coalification,the long-term average carbon accumulation rate and net primary productivity(NPP)of paleo-peatlands in coal seams can be *** review paper presents the procedures of analysis,assessment of results and interpretation of geophysical logs in determining the NPP of paleo-peatlands.

关键词： paleo-peatlands Milankovitch cycle carbon accumulation rate net primary productivity(NPP) coal seam

Influence of depositional environment on coalbed methane accumulation in the Carboniferous-Permian coal of the Qinshui Basin, northern China

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Frontiers of Earth Science 2019年第3期13卷 535-550页

作者： Haihai HOU Longyi SHAO Shuai wang Zhenghui XIAO xuetian wang Zhen LI College of Geoscience and Surveying Engineering China University of Mining and TechnologyBeijing 100083China College of Mining Liaoning Technical UniversityFuxin 123000China School of Civil Engineering Hunan University of Science and TechnologyXiangtan 411201China

Based on analyses of the lithofacies palaeo-geography of the Taiyuan and the Shanxi Formations in the Qinshui Basin, the spatial variations of the coal seam thickness, coal maceral composition, coal quality, and gas content, together with the lithofacies of the surrounding rocks in each palaeogeographic unit were investigated. The results show that the thick coals of the Taiyuan Formation are mainly distributed in delta and barrier island depositional units in the Yangquan area in the northern part of the basin and the Zhangzi area in the southeastern part of the basin. The thick coals of the Shanxi Formation are located within transitional areas between delta plain and delta front depositional units in the central southern part of the basin. The Taiyuan Formation generally includes mudstone in its lower part, thick, continuous coal seams and limestones in its middle part, and thin, discontinuous coal seams and limestone and sand-mud interbeds in its top part. The Shanxi Formation consists of thick, continuous sandstones in its lower part, thick coal seams in its middle part, and thin coal seams, sandstone, and thick mudstone in its upper part. From the perspective of coal-bearing sedimentology and coalbed methane (CBM) geology, the lithology and thickness of the surrounding rocks of coal seams play more significant roles in controlling gas content variation than other factors such as coal thickness, coal macerals, and coal quality. Furthermore, it is found that the key factors influencing the gas content variation are the thicknesses of mudstone and limestone overlying a coal seam. At similar burial depths, the gas content of the Taiyuan coal seams decreases gradually in the lower delta plain, barrier-lagoon,delta front, barrier-tidal flat, and carbonate platform depositional units. The CBM enrichment areas tend to be located in zones of poorly developed limestone and well-developed mudstone. In addition, the gas content of the Shanxi Formation is higher in the coa

关键词： depositional environment coalbed methane enrichment condition gas content Taiyuan Formation Shanxi Formation

Sequence stratigraphy, paleogeography, and coal accumulation regularity of major coal-accumulating periods in China

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International Journal of Coal Science & Technology 2020年第2期7卷 240-262页

作者： Longyi Shao xuetian wang Dongdong wang Mingpei Li Shuai wang Yingjiao Li Kai Shao Chao Zhang Caixia Gao Daxiao Dong Aiguo Cheng Jing Lu Congwei Ji Di Gao State Key Laboratory of Coal Resources and Safe Mining College of Geoscience and Surveying EngineeringChina University of Mining and Technology(Beijing)Beijing 100083China College of Earth Science and Engineering Shandong University of Science and TechnologyQingdao 266590ShandongChina Innovation Technology Research Institute of Shaanxi Investment Group Co. Ltd.Xi'an 710061ShaanxiChina Shaanxi Coalbed Methane Development Company Limited Xi'an 710119ShaanxiChina China National Administration of Coal Geology Beijing 100039China College of Resources and Environment Henan Polytechnic UniversityJiaozuo 454003HenanChina

There are 9 major coal-accumulating periods during geological history in China,including the Early Carboniferous,Late Carboniferous-Early Permian,Middle Permian,Late Permian,Late Triassic,Early-Middle Jurassic,Early Cretaceous,Paleogene and *** coal formed in these periods were developed in different coal-accumulating areas(CAA)including the North China,South China,Northwest China,Northeast China,the Qinghai–Tibet area,and China offshore *** this paper,we investigated depositional environments,sequence stratigraphy,lithofacies paleogeography and coal accumulation pattern of five major coal-accumulating periods including the Late Carboniferous to Middle Permian of the North China CAA,the Late Permian of the South China CAA,the Late Triassic of the South China CAA,the Early-Middle Jurassic of the North and Northwest China CAA,and the Early Cretaceous in the Northeast China *** to distribution of the coal-bearing strata and the regional tectonic outlines,we have identified distribution range of the coal-forming basins,sedimentary facies types and coal-accumulating *** sequence stratigraphic frameworks of the major coal-accumulating periods were established based on recognition of a variety of sequence *** distribution of thick coals and migration patterns of the coal-accumulating centers in the sequence stratigraphic framework were *** lithofacies paleogeography maps based on third-order sequences were reconstructed and the distribution of coal accumulation centers and coal-rich belts were predicted.

关键词： Coal-accumulating period Coal-accumulating area Sequence stratigraphy Paleogeography China

厚煤层成因机制——天文周期控制的多期次泥炭沼泽叠加模式

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煤炭科学技术 2022年第1期50卷 186-195页

作者：邵龙义党星宇高祥宇王东东温和王学天高迪鲁静中国矿业大学(北京)地球科学与测绘工程学院北京100083 山东科技大学地球科学与工程学院山东青岛266590 河南理工大学资源与环境学院河南焦作454003

蕴含丰富地质信息的厚煤层是重要的地质碳库及地质信息库,我国是煤炭资源大国,华北、西北、东北、华南等聚煤区都发育有厚煤层。传统煤田地质学认为,厚煤层是泥炭沼泽潜水面上升速度与植物遗体聚集速度长期处于均衡补偿状态下的连续聚... 详细信息

蕴含丰富地质信息的厚煤层是重要的地质碳库及地质信息库,我国是煤炭资源大国,华北、西北、东北、华南等聚煤区都发育有厚煤层。传统煤田地质学认为,厚煤层是泥炭沼泽潜水面上升速度与植物遗体聚集速度长期处于均衡补偿状态下的连续聚集产物。但现今发育的泥炭沼泽单层最大厚度仅为20 m,考虑泥炭到烟煤成煤过程受到高达约6∶1的压实比例,均衡补偿成因解释厚煤层的形成可能存在一定的不合理性。基于煤岩学、层序地层学、旋回地层学的理论和研究方法,对不同盆地厚煤层中反映气候变化的天文周期信息开展研究。结果表明,厚煤层中煤岩显微组分以及灰分在垂向上的周期性变化和沉积间断面的存在,是多期次泥炭沼泽叠加形成厚煤层的重要依据。泥炭沼泽多期次叠加及厚煤层中煤岩显微组分的周期性变化均受当时的气候环境演化影响,而气候环境的演化又受控于天文周期。综合已有的厚煤层成因观点和实例研究,提出受天文周期控制的多期次泥炭沼泽叠加成煤理论和模型,用于解释厚煤层的成因机制。

关键词：厚煤层天文周期多期次泥炭沼泽叠加成因模式煤岩显微组分煤的间断面

乐平统含煤岩系旋回地层的天文周期驱动:以黔西北毕节地区为例

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矿业科学学报 2022年第1期7卷 89-100页

作者：高祥宇邵龙义王学天华芳辉鲁静中国矿业大学(北京)地球科学与测绘工程学院北京100083 煤炭资源与安全开采国家重点实验室北京100083

为了系统地研究黔西北毕节地区乐平统含煤岩系中存在的沉积旋回及其天文周期驱动,本文采用时间序列分析法和相关系数法对该地区4个钻孔剖面的自然伽马(GR)测井数据进行旋回地层学分析与天文检验。旋回分析结果显示,研究区乐平统含煤岩... 详细信息

为了系统地研究黔西北毕节地区乐平统含煤岩系中存在的沉积旋回及其天文周期驱动,本文采用时间序列分析法和相关系数法对该地区4个钻孔剖面的自然伽马(GR)测井数据进行旋回地层学分析与天文检验。旋回分析结果显示,研究区乐平统含煤岩系记录了405 kyr长偏心率、125 kyr和95 kyr短偏心率、40.6 kyr和33 kyr地轴斜率周期信息,并且可识别出17个由405 kyr长偏心率周期驱动形成的旋回;天文检验结果显示,乐平统含煤岩系受到天文周期驱动的可能性大于99%。根据识别出的沉积旋回并结合前人在西南地区的层序划分结果,在研究区乐平统建立了高分辨率层序地层格架,划分出3个三级层序和17个四级层序,同时在经过调谐后得到的时间标尺上加以精确的年龄约束,建立了乐平统的天文年代标尺。对层序地层格架和年代标尺的综合分析表明,乐平统的沉积时限在6.47~7.16 Myr之间,并且底部存在0.69 Myr的穿时现象,3个三级层序的沉积时限分别是2.34 Myr、1.98 Myr、2.84 Myr。最后分析和总结了各三级层序的沉积速率变化规律,乐平统平均沉积速率在2.91~4.11 cm/kyr之间,CSⅠ的沉积速率整体呈现出“慢—快”或“快—慢—快”的变化趋势,CSⅡ沉积速率变化规律不明显,CSⅢ整体呈现出“快—慢—快—慢—快”的变化趋势。本研究所建立的层序地层格架可为毕节地区乐平统煤系高精度的地层对比提供参考,同时所建立的天文年代标尺可为研究乐平世古气候、古环境和重大历史事件的演化提供高分辨率的年代地层框架。

关键词：毕节乐平统旋回地层学天文检验高分辨率层序地层格架天文年代标尺

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平坦地面条件下装备间天线电磁耦合度分析

电波科学学报 2015年第4期30卷 814-819页

作者：王伟王学田王文宋崧李名游陈磊北京理工大学信息与电子学院北京100081 中国人民解放军装备学院北京101416

分析了地表面反射系数以及地面土壤介质的介电特性,研究了车体结构对天线辐射特性的影响,仿真得到了车体模型、地面介质、距离等因素对天线间耦合度的影响,建立了平坦地面条件下,通信车的收发天线间电磁耦合度的精确的仿真模型.经与实... 详细信息

分析了地表面反射系数以及地面土壤介质的介电特性,研究了车体结构对天线辐射特性的影响,仿真得到了车体模型、地面介质、距离等因素对天线间耦合度的影响,建立了平坦地面条件下,通信车的收发天线间电磁耦合度的精确的仿真模型.经与实测数据对比分析,仿真结果与实测数据变化规律一致,最大误差16.54dB,均方差4.21dB.

关键词：反射系数介电特性平原地貌电磁耦合度

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一种甚高频中心和带宽可调耦合滤波器设计

电波科学学报 2013年第2期28卷 285-289页

作者：房丽丽王学田刘春明北京理工大学信息与电子学院北京100081

针对两种典型的电调谐耦合滤波器结构,研究了在滤波器中心频率改变时如何保持滤波带宽恒定的问题.采用LC集总元件,考虑实际元件的寄生效应,提出了VHFL频段中心频率和带宽可调的双调谐耦合滤波器结构。仿真结果表明:该滤波器在56.9～165.... 详细信息

针对两种典型的电调谐耦合滤波器结构,研究了在滤波器中心频率改变时如何保持滤波带宽恒定的问题.采用LC集总元件,考虑实际元件的寄生效应,提出了VHFL频段中心频率和带宽可调的双调谐耦合滤波器结构。仿真结果表明:该滤波器在56.9～165.8MHz的可调范围内,电路频率选择性能良好,且矩形系数(30dB/3dB)小于7,保持接近常数的带宽.实际电路的测试结果验证了设计的有效性.

关键词：电调谐耦合滤波器变容二极管

基于定量古地理的BQART模型深时古地势重建方法——以晚二叠世峨眉山大火成岩省内带为例

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沉积学报 2022年第6期40卷 1461-1480页

作者：王学天邵龙义 Kenneth A.Eriksson 胡修棉刘钦甫鲁静中国矿业大学(北京)地球科学与测绘工程学院北京100083 煤炭资源与安全开采国家重点实验室北京100083 Department of Geosciences Virginia TechBlacksburgBlacksburgVA 24061USA 南京大学地球科学与工程学院南京210023

源—汇系统分析下的古地势重建是当前沉积学领域的一个热点方向。古地势重建对于理解区域构造演化、气候变化、地表风化、物源供给及其相互关系具有重要作用。BQART沉积通量模型提供了入海流域中沉积通量与地质背景B、水流量Q、流域面积... 详细信息

源—汇系统分析下的古地势重建是当前沉积学领域的一个热点方向。古地势重建对于理解区域构造演化、气候变化、地表风化、物源供给及其相互关系具有重要作用。BQART沉积通量模型提供了入海流域中沉积通量与地质背景B、水流量Q、流域面积A、最大地势高度R、年均温度T之间的经验关系,逐渐发展为深时尺度下古流域地势重建的重要工具。本文在综合层序—古地理、旋回地层学、古水文比例关系和古地貌比例关系等方法的基础上,提出基于定量古地理的BQART模型深时古地势重建方法,结合沉积体积回填法可进一步获得构造抬升幅度与速率。通过该方法获得峨眉山大火成岩省内带古地势在晚二叠世期间持续缓慢上升,至晚二叠世末达200余米,累计构造抬升幅度约500~750 m。该深时古地势方法适用于气候温暖湿润、构造相对稳定条件下的中大型外流盆地,对能源盆地的勘探开发具有重要意义。

关键词： BQART模型沉积通量定量古地理源—汇系统古地势晚二叠世峨眉山大火成岩省