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大地电磁单分量精准处理技术与深部致灾水体探测

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煤田地质与勘探 2022年第12期50卷 142-151页

作者：李沛涛武强李卓融李文雨谢建王玉喜中国矿业大学(北京)国家煤矿水害防治工程技术研究中心北京100083 北京邮电大学人工智能学院北京100081 郑州煤炭工业(集团)有限责任公司河南郑州450081 河南景惠科技有限公司河南郑州450042

为了实现天然源单分量大地电磁技术对水文地质条件的精细探测,系统分析了大地电磁信号采集和处理中存在的问题,研究了地下富水区在大地电磁波上的响应特征;根据大地电磁测深理论和层次分析法,建立了富水性指数模型;在大量实验数据的基础... 详细信息

为了实现天然源单分量大地电磁技术对水文地质条件的精细探测,系统分析了大地电磁信号采集和处理中存在的问题,研究了地下富水区在大地电磁波上的响应特征;根据大地电磁测深理论和层次分析法,建立了富水性指数模型;在大量实验数据的基础上,拟合波形和岩性的对应关系,从波形上分维提取岩层的介电常数、弹脆性、密度、空隙率等物性信息,按有利于岩层富水的原则赋值和归一化处理,纳入富水性指数模型进行多维度耦合计算,可得到相应深度的富水性指数值。富水性指数包含了丰富的岩层物性信息,增强了富水区在大地电磁波上的响应幅度,减小了天然场源强度变化对信号采集和识别的影响。根据富水性指数模型,利用现代计算机及通信技术,设计了双层阵列扫频式平行板电容传感器和大地电磁探水仪,并开发出了相应的数据处理程序,探测深度分辨率可达0.1 m,能够从庞杂的电磁信号中自动辨识来自深部的微弱信号,实现从时变性场源中采集信号并计算出相对稳定的富水性指数。经现场试验,仪器可清楚划分含水层和隔水层,识别富水区和微小导水通道。该技术在矿井水害防治、废弃采空区修复治理、注浆堵水、深部水文地质条件探测等工程中具有广阔的应用前景。

关键词：天然源大地电磁阵列扫频式富水性指数模型分维识别

基于深度卷积神经网络的地震震相拾取方法研究

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地球物理学报 2020年第4期63卷 1591-1606页

作者：李健王晓明张英海王卫东商杰盖磊北京邮电大学电子工程学院北京100876 禁核试北京国家数据中心和北京放射性核素试验室北京100085

地震震相拾取是地震数据自动处理的首要环节,包括了信号检测、到时估计和震相识别等过程,震相拾取的准确性直接影响到后续事件关联处理的性能,影响观测报告的质量.为了提高震相拾取的准确性,进而提高观测报告质量,本文采用深度卷积神经... 详细信息

地震震相拾取是地震数据自动处理的首要环节,包括了信号检测、到时估计和震相识别等过程,震相拾取的准确性直接影响到后续事件关联处理的性能,影响观测报告的质量.为了提高震相拾取的准确性,进而提高观测报告质量,本文采用深度卷积神经网络方法来解决震相拾取问题,构建了多任务卷积神经网络模型,设计了分类和回归的联合损失函数,定义了基于加权的分类损失函数,以三分量地震台站的波形数据作为输入,同时实现对震相的检测识别和到时的精确估计.利用美国南加州地震台网的200万条震相和噪声数据对模型进行训练、验证和测试,对于测试集中直达波P、S震相识别的查全率达到98%以上,到时估计的标准偏差分别为0.067s,0.082s.利用迁移学习和数据增强,将模型用于对我国东北地区台网的6个台站13.00条数据的训练、验证和测试中,对该数据集P、S震相查全率分别达到91.21%、85.65%.基于迁移训练后的模型,设计了用于连续数据的震相拾取方法,利用连续的地震数据对该算法进行了实际应用测试,并与国家数据中心和中国地震局的观测报告进行比对,该方法的震相检测识别率平均可达84.5%,验证了该方法在实际应用中的有效性.本文所提出的方法展示了深度神经网络在地震震相拾取中的优异性能,为地震震相和事件的检测识别提供了新的思路.

关键词：多任务卷积神经网络震相拾取联合损失函数迁移学习

Mapping essential urban land use categories in china(EULUC-china):preliminary results for 2018

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Science Bulletin 2020年第3期65卷 182-187页

作者： Peng Gong Bin Chen Xuecao li Han liu Jie wang Yuqi Bai Jingming Chen Xi Chen Lei Fang Shuailong Feng Yongjiu Feng Yali Gong Hao Gu Huabing Huang Xiaochun Huang Hongzan Jiao Yingdong Kang Guangbin Lei Ainong li Xiaoting li xun li Yuechen li Zhilin li Zhongde li Chong liu Chunxia liu Maochou liu Shuguang liu Wanliu Mao Changhong Miao Hao Ni Qisheng Pan Shuhua Qi Zhehao Ren Zhuoran Shan Shaoqing Shen Minjun Shi Yimeng Song Mo Su Hoi Ping Suen Bo Sun Fangdi Sun jian Sun lin Sun Wenyao Sun Tian Tian Xiaohua Tong Yihsing Tseng Ying Tu Hong wang Lan wang Xi Wan Zongming wang Tinghai Wu Yaowen Xie jian {23. Jun {23. Man Yuan Wenze Yue Hongda Zeng Kuo Zhang Neng Zhang Tao Zhang Yu Zhang Feng Zhao Yichen Zheng Qiming Zhou Nicholas Clinton Zhiliang Zhu Bing Xu Ministry of Education Key Laboratory for Earth System Modeling Department of Earth System ScienceTsinghua UniversityBeijing 100084China Tsinghua Urban Institute Tsinghua UniversityBeijing 100084China Center for Healthy Cities Institute for China Sustainable UrbanizationTsinghua UniversityBeijing 100084China Department of Land Air and Water ResourcesUniversity of CaliforniaDavisCA 95616-8627USA Department of Geological and Atmospheric Sciences Iowa State UniversityAmesIA 50011USA State Key Laboratory of Remote Sensing Science Institute of Remote Sensing and Digital EarthChinese Academy of SciencesBeijing 100101China AI for Earth Laboratory Cross-Strait InstituteTsinghua UniversityBeijing 100084China International Institute for Earth System Sciences Nanjing UniversityNanjing 210093China Research Center for Ecology and Environment of Central Asia Chinese Academy of SciencesUrumchi 830011China Key Laboratory of Forest Ecology and Management Institute of Applied EcologyChinese Academy of SciencesShenyang 110016China National engineering Laboratory for Applied Technology in Forestry&Ecology in South china College of Life Science and TechnologyCentral South University of Forestry and TechnologyChangsha 410004China College of Surveying&Geo-Informatics Tongji UniversityShanghai 200092China Department of Urban Planning College of Architecture and Urban PlanningTongji UniversityShanghai 200092China beijing Institute of Urban Planning Beijing 100045China Department of Urban Planning School of Urban DesignWuhan UniversityWuhan 430072China College of Earth Sciences Jilin UniversityChangchun 130061China Research Center for Digital Mountain and Remote Sensing Application Institute of Mountain Hazards and EnvironmentChinese Academy of SciencesChengdu 610041China Institute of Remote Sensing and Geographic information System School of Earth and Space SciencesPeking UniversityBeijing 100871China Department of Urban and Regional Planning School of Geography and PlanningSun Yat-sen Univ

Land use reflects human activities on *** land use is the highest level human alteration on Earth,and it is rapidly changing due to population increase and *** areas have widespread effects on local hydrology,climate,biodiversity,and food production[1,2].However,maps,that contain knowledge on the distribution,pattern and composition of various land use types in urban areas,are limited to city *** mapping standard on data sources,methods,land use classification schemes varies from city to city,due to differences in financial input and skills of mapping *** address various national and global environmental challenges caused by urbanization,it is important to have urban land uses at the national and global scales that are derived from the same or consistent data sources with the same or compatible classification systems and mapping *** is because,only with urban land use maps produced with similar criteria,consistent environmental policies can be made,and action efforts can be compared and assessed for large scale environmental ***,despite of the fact that a number of urban-extent maps exist at global scales[3.4],more detailed urban land use maps do not exist at the same *** at big country or regional levels such as for the United States,{3. and European Union,consistent land use mapping efforts are rare[5,6](e.g.,https://***/open_land_use/).

关键词： EULUC-china 土地利用类型

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基于形态学的红外图像边缘检测

北京邮电大学学报 2021年第1期44卷 66-71页

作者：王睿男武穆清陈铁英李志刚孙建北京邮电大学信息与通信工程学院北京100876 浙江梧斯源通信科技股份有限公司杭州310030

为了提高红外图像边缘检测的性能,提出了一种基于形态学的红外图像边缘检测算法,改进了仅依靠单一方向和采用固定方向权重的边缘检测算法.通过使用多方向结构元素对图像边缘进行提取,采用方向自适应权重进行加权融合,得到图像边缘检测... 详细信息

为了提高红外图像边缘检测的性能,提出了一种基于形态学的红外图像边缘检测算法,改进了仅依靠单一方向和采用固定方向权重的边缘检测算法.通过使用多方向结构元素对图像边缘进行提取,采用方向自适应权重进行加权融合,得到图像边缘检测的结果.实验结果表明,该方法能够有效地抑制图像中的噪声,提取的图像边缘更加完整,提高了红外图像边缘检测的效果.

关键词：边缘检测红外图像形态学自适应权重

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激光星间链路终端技术发展与展望

光学技术 2023年第2期49卷 175-183页

作者：夏方园汪勃张国亭伍剑张建华陈祥张福瑞李瑶北京跟踪与通信技术研究所北京100094 北京邮电大学电子工程学院北京100083 西安空间无线电技术研究所西安710199 西安工业大学光电工程学院陕西西安710021

激光星间链路主要用于卫星之间高速数传,是构建天基信息网络的关键技术。目前国外通信、遥感、导航和中继等卫星系统都已计划部署激光通信终端,激光星间链路技术已从在轨演示验证向大规模组网应用阶段发展。简要梳理了国际上现有组网卫... 详细信息

激光星间链路主要用于卫星之间高速数传,是构建天基信息网络的关键技术。目前国外通信、遥感、导航和中继等卫星系统都已计划部署激光通信终端,激光星间链路技术已从在轨演示验证向大规模组网应用阶段发展。简要梳理了国际上现有组网卫星系统的激光星间链路终端技术发展情况,对激光星间链路的技术体制和终端分类进行了总结;侧重分析了我国激光星间链路终端技术发展现状及大规模应用面临的主要问题,针对重难点技术的解决途径进行了思考;对激光星间链路终端未来的发展趋势做了展望,尤其是轻小型化设计与实现、宽带化、一对多光学天线和网络化等技术发展趋势进行了分析。

关键词：星间链路激光通信通信与测量小型化发展与展望

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可见光通信定位集成系统仿真研究

光通信研究 2019年第2期2期(16)卷 15-18页

作者：陈浩哲丁俊杰吴昊杨铭锐王颖游善红胡剑凌曹洪龙李响周鸣籁苏州大学电子信息学院江苏苏州215006 中国科学院大学电子电气与通信工程学院北京101408 武汉邮电科学研究院有限公司光纤通信技术和网络国家重点实验室武汉430074

为了提升可见光通信(VLC)定位系统的频谱和功率利用率,文章提出了一种基于非对称限幅和直流偏置的光正交频分复用(ADO-OFDM)的VLC定位集成系统。该通信定位集成系统具有比基于非对称限幅的光正交频分复用(ACO-OFDM)的VLC定位集成系统更... 详细信息

为了提升可见光通信(VLC)定位系统的频谱和功率利用率,文章提出了一种基于非对称限幅和直流偏置的光正交频分复用(ADO-OFDM)的VLC定位集成系统。该通信定位集成系统具有比基于非对称限幅的光正交频分复用(ACO-OFDM)的VLC定位集成系统更高的频谱利用率和比基于加直流偏置的光正交频分复用(DCO-OFDM)的VLC定位集成系统更高的功率利用率。同时,文章还提出了一种差分修正定位算法,所提算法较于传统的三边定位算法其具有更高的定位精度。

关键词：可见光通信通信定位集成系统非对称限幅和直流偏置的光正交频分复用系统差分修正定位算法

面向重大自然灾害的救援装备研究现状及发展趋势

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科学技术与工程 2021年第25期21卷 10552-10565页

作者：张新徐建华陈彤王军政赵江波仲军李兰芸韩震峰李宏伟李顺赵方訾栓紧新兴际华科技发展有限公司高端装备研究院北京100070 新兴际华集团有限公司技术中心北京100070 北京理工大学自动化学院北京100081 河海大学机电工程学院常州213022 哈工大机器人(合肥)国际创新研究院无人装备研究所合肥230601 北京北方车辆集团有限公司北京市特种车辆关键部件制备与评估工程技术研究中心北京100072 北京邮电大学软件学院北京100876 中国消防救援学院信息工程系北京102202

随着地震、地质及洪涝等自然灾害多发频发,救援装备成为救灾应急力量体系的重要组成部分,中外围绕高机动、多功能、模块化、轻量化救援装备展开了深入的研究和应用。从快速抵达、救援处置、装备转场、协同救援及解决救援现场最后一公里... 详细信息

随着地震、地质及洪涝等自然灾害多发频发,救援装备成为救灾应急力量体系的重要组成部分,中外围绕高机动、多功能、模块化、轻量化救援装备展开了深入的研究和应用。从快速抵达、救援处置、装备转场、协同救援及解决救援现场最后一公里的难题对中外的救援装备进行了论述,同时对中外救援装备的特点和性能进行了对比分析,提出了现有救援装备面临挑战问题,在此基础上提出了救援装备发展的方向和发展趋势,同时对救援机器人的发展进行了展望,以期对中国的应急救援装备的发展和处置能力的提升提供参考和借鉴。

关键词：自然灾害救援装备机械臂

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二维材料最新研究进展

物理化学学报 2021年第12期37卷 1-151页

作者：常诚陈伟陈也陈永华陈雨丁峰樊春海范红金范战西龚成宫勇吉何其远洪勋胡晟胡伟达黄维黄元季威李德慧李连忠李强林立凌崇益刘鸣华刘楠刘庄 Kian Ping Loh 马建民缪峰彭海琳邵明飞宋礼苏邵孙硕谭超良唐智勇王定胜王欢王金兰王欣王欣然 Andrew T.S.Wee 魏钟鸣吴宇恩吴忠帅熊杰熊启华徐伟高尹鹏曾海波曾志远翟天佑张晗张辉张其春张铁锐张翔赵立东赵美廷赵伟杰赵运宣周凯歌周兴周喻朱宏伟张华刘忠范 Institute of Science and Technology Austria Am Campus 13400 KlosterneuburgAustria Department of Chemistry National University of Singapore3 Science Drive 3117543Singapore Department of Chemistry The Chinese University of Hong KongShatinNew TerritoriesHong KongChina Key Laboratory of Flexible Electronics and Institute of Advanced Materials Nanjing Tech UniversityNanjing 211816China school of life Sciences Shanghai UniversityShanghai 200444China Centre for Multidimensional Carbon Materials Institute for Basic ScienceUlsan 44919Korea school of Chemistry and Chemical engineering Shanghai Jiao Tong UniversityShanghai 200240China school of Physical and Mathematical Sciences Nanyang Technological UniversitySingapore 637371Singapore Department of Chemistry City University of Hong KongKowloonHong KongChina Department of Electrical and Computer engineering and Quantum Technology Center University of MarylandCollege ParkMaryland 20742USA school of Materials Science and engineering Beihang UniversityBeijing 100191China Department of Materials Science and engineering City University of Hong KongKowloonHong KongChina Center of Advanced Nanocatalysis(CAN) Hefei National Laboratory for Physical Sciences at the MicroscaleDepartment of Applied ChemistryUniversity of Science and Technology of ChinaHefei 230026China College of Chemistry and Chemical engineering State Key Laboratory of Physical Chemistry of Solid SurfacesCollaborative Innovation Center of Chemistry for Energy Materials(iChEM)Xiamen UniversityXiamen361005Fujian ProvinceChina State Key Laboratory of Infrared Physics Shanghai Institute of Technical PhysicsChinese Academy of SciencesShanghai 200083China Advanced Research Institute of Multidisciplinary Science Beijing Institute of TechnologyBeijing100081China beijing Key Laboratory of Optoelectronic Functional Materials&Micro-Nano Devices Department of PhysicsRenmin University of ChinaBeijing 100872China school of Optical and Electronic information Wuhan National Laboratory

Research on two-dimensional(2D) materials has been explosively increasing in last seventeen years in varying subjects including condensed matter physics, electronic engineering, materials science, and chemistry since the mechanical exfoliation of graphene in 2004. Starting from graphene, 2D materials now have become a big family with numerous members and diverse categories. The unique structural features and physicochemical properties of 2D materials make them one class of the most appealing candidates for a wide range of potential applications. In particular, we have seen some major breakthroughs made in the field of 2D materials in last five years not only in developing novel synthetic methods and exploring new structures/properties but also in identifying innovative applications and pushing forward commercialisation. In this review, we provide a critical summary on the recent progress made in the field of 2D materials with a particular focus on last five years. After a brief backgroundintroduction, we first discuss the major synthetic methods for 2D materials, including the mechanical exfoliation, liquid exfoliation, vapor phase deposition, and wet-chemical synthesis as well as phase engineering of 2D materials belonging to the field of phase engineering of nanomaterials(PEN). We then introduce the superconducting/optical/magnetic properties and chirality of 2D materials along with newly emerging magic angle 2D superlattices. Following that, the promising applications of 2D materials in electronics, optoelectronics, catalysis, energy storage, solar cells, biomedicine, sensors, environments, etc. are described sequentially. Thereafter, we present the theoretic calculations and simulations of 2D materials. Finally, after concluding the current progress, we provide some personal discussions on the existing challenges and future outlooks in this rapidly developing field.

关键词： Two-dimensional materials Transition metal dichalcogenides Phase engineering of nanomaterials Electronics Optoelectronics Catalysis Energy storage and conversion