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Three-dimensional Fusion of Spaceborne and Ground Radar Reflectivity Data Using a Neural Network–Based Approach

Advances in Atmospheric Sciences 2018年第3期35卷 346-359页

作者： leilei kou Zhuihui WANG Fen XU Key Laboratory of Meteorological Disaster Ministry of Education/Joint International Research Laboratory of Climate and Environment Change/Collaborative Innovation Center on Forecast and Evaluation of Meteorological DisastersNanjing University of Information Science and Technology Nanjing 210044 China Meteorological Bureau of Jiangsu Province Nanjing 210008 China

The spaceborne precipitation radar onboard the Tropical Rainfall Measuring Mission satellite （TRMM PR） can provide good measurement of the vertical structure of reflectivity, while ground radar （GR） has a relatively high horizontal resolution and greater sensitivity. Fusion of TRMM PR and GR reflectivity data may maximize the advantages from both instruments. In this paper, TRMM PR and GR reflectivity data are fused using a neural network （NN）-based approach. The main steps included are： quality control of TRMM PR and GR reflectivity data; spatiotemporal matchup; GR calibration bias correction; conversion of TRMM PR data from Ku to S band; fusion of TRMM PR and GR reflectivity data with an NN method： interpolation of reflectivity data that are below PR＇s sensitivity; blind areas compensation with a distance weighting-based merging approach; combination of three types of data： data with the NN method, data below PR＇s sensitivity and data within compensated blind areas. During the NN fusion step, the TRMM PR data are taken as targets of the training NNs, and gridded GR data after horizontal downsampling at different heights are used as the input. The trained NNs are then used to obtain 3D high-resolution reflectivity from the original GR gridded data. After 3D fusion of the TRMM PR and GR reflectivity data, a more complete and finer-scale 3D radar reflectivity dataset incorporating characteristics from both the TRMM PR and GR observations can be obtained. The fused reflectivity data are evaluated based on a convective precipitation event through comparison with the high resolution TRMM PR and GR data with an interpolation algorithm.

关键词： TRMM PR ground radar 3D fusion neural network

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High sidelobe effects on interferometric coherence for circular SAR imaging geometry

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Journal of Systems Engineering and Electronics 2013年第1期24卷 76-83页

作者： leilei kou Xiaoqing Wang Maosheng Xiang Minhui Zhu School of Atmospheric Physics Nanjing University of Information Science and Technology Institute of Electronics Chinese Academy of Sciences

The coherence is a measure for the accuracy of the interferometric phase, and the synthetic aperture radar （SAR） inter- ferometric coherence is affected by several sources of the decor- relation noise. For the circular SAR （CSAR） imaging geometry, the system response function is in the form of the Bessel function which brings a high sidelobe, and the high sidelobe of CSAR will be an important factor influencing the interferometric coherence. The effect of the high sidelobe on the coherence is analyzed and deduced. Based on the interferometric characteristics of the slight difference in the viewing angles and the potential pixel off- set in the interferometric SAR （InSAR） images, a relation between the radar impulse response and the coherence loss function is derived. From the relational model, the coherence loss function due to the high sidelobe of CSAR is then deduced, and compared with that of the conventional SAR. It is shown that the high sidelobe of CSAR focusing signal will severely affect the baseline decorre- lation and coregistration decorrelation. Simulation results confirm the theoretical analysis and quantitatively show the baseline and coregistration decorrelation degradation due to the high sidelobes of CSAR.

关键词： interferometric coherence circular SAR (CSAR) high sidelobe interferometric SAR (InSAR) baseline decorrelation coregistration decorrelation.

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Statistical Modeling with a Hidden Markov Tree and High-resolution Interpolation for Spaceborne Radar Reflectivity in the Wavelet Domain

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Advances in Atmospheric Sciences 2020年第12期37卷 1359-1374页

作者： leilei kou Yinfeng JIANG Aijun CHEN Zhenhui WANG Key Laboratory of Meteorological Disaster Ministry of Education/Joint International Research Laboratory of Climate and Environment Change/Collaborative Innovation Center on Forecast and Evaluation of Meteorological DisastersNanjing University of Information Science&TechnologyNanjing 210044China Nanjing University of Information Science&Technology Nanjing 210044China

With the increasing availability of precipitation radar data from space,enhancement of the resolution of spaceborne precipitation observations is important,particularly for hazard prediction and climate modeling at local scales relevant to extreme precipitation intensities and *** this paper,the statistical characteristics of radar precipitation reflectivity data are studied and modeled using a hidden Markov tree(HMT)in the wavelet ***,a high-resolution interpolation algorithm is proposed for spaceborne radar reflectivity using the HMT model as prior *** to the small and transient storm elements embedded in the larger and slowly varying elements,the radar precipitation data exhibit distinct multiscale statistical properties,including a non-Gaussian structure and scale-to-scale *** HMT model can capture well the statistical properties of radar precipitation,where the wavelet coefficients in each sub-band are characterized as a Gaussian mixture model(GMM),and the wavelet coefficients from the coarse scale to fine scale are described using a multiscale Markov *** state probabilities of the GMM are determined using the expectation maximization method,and other parameters,for instance,the variance decay parameters in the HMT model are learned and estimated from high-resolution ground radar reflectivity *** the prior model,the wavelet coefficients at finer scales are estimated using local Wiener *** interpolation algorithm is validated using data from the precipitation radar onboard the Tropical Rainfall Measurement Mission satellite,and the reconstructed results are found to be able to enhance the spatial resolution while optimally reproducing the local extremes and gradients.

关键词： spaceborne precipitation radar hidden Markov tree model Gaussian mixture model interpolation in the wavelet domain multiscale statistical properties

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Circular SAR processing using an improved omega-k type algorithm

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Journal of Systems Engineering and Electronics 2010年第4期21卷 572-579页

作者： leilei kou Xiaoqing Wang Jinsong Chong Maosheng Xiang Minhui Zhu National Key Laboratory of Microwave Imaging Technology Institute of Electronics Chinese Academy of Sciences Beijing 100190 P. R. China Graduate University of Chinese Academy of Sciences Beijing 100049 P. R. China

An improved circular synthetic aperture radar（CSAR） imaging algorithm of omega-k（ω-k） type mainly for reconstructing an image on a cylindrical surface is *** the typical CSAR ω-k algorithm,the rage trajectory is approximated by Taylor series expansion to the quadratic terms,which limits the valid synthetic aperture length and the angular reconstruction range *** on the model of the CSAR echo signal,the proposed algorithm directly transforms the signal to the two-dimensional（2D） wavenumber domain,not using approximation processing to the range *** on form of the signal spectrum in the wavenumber domain,the formula for the wavenumber domain interpolation of the w-k algorithm is deduced,and the wavenumber spectrum of the reference point used for bulk compression is obtained from numerical *** improved CSAR ω-k imaging algorithm increases the valid synthetic aperture length and the angular area greatly and hence improves the angular resolution of the cylindrical ***,the proposed algorithm can be repeated on different cylindrical surfaces to achieve three dimensional（3D） image *** 3D spatial resolution of the CSAR system is discussed,and the simulation results validate the correctness of the analysis and the feasibility of the algorithm.

关键词： circular synthetic aperture radar omega-k algorithm wavenumber domain three-dimensional spatial resolution.

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Fusion of Ground-Based and Spaceborne Radar Precipitation Based on Spatial Domain Regularization

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Journal of Meteorological Research 2024年第2期38卷 285-302页

作者： Anfan HUANG leilei kou Yanzhi LIANG Ying MAO Haiyang GAO Zhigang CHU School of Atmospheric Physics Nanjing University of Information Science&TechnologyNanjing 210044 Collaborative Innovation Center on Forecast and Evaluation of Meteorological Disasters Nanjing University of Information Science&TechnologyNanjing 210044

High-quality and accurate precipitation estimations can be obtained by integrating precipitation information measures using ground-based and spaceborne radars in the same target *** the true precipitation state is a typical inverse problem for a given set of noisy radar precipitation *** regularization method can appropriately constrain the inverse problem to obtain a unique and stable *** different types of precipitation with different prior distributions,the L_(1) and L_(2) norms were more effective in constraining stratiform and convective precipitation,*** a combination of L_(1) and L_(2) norms,the Huber norm is more suitable for mixed precipitation *** study uses different regularization norms to combine precipitation data from the C-band dual-polarization ground radar(CDP)and dual-frequency precipitation radar(DPR)on the Global Precipitation Measurement(GPM)mission core *** to single-source radar data,the fused figures contain more information and present a comprehensive precipitation structure encompassing the reflectivity and precipitation *** 27 precipitation cases,the fusion results utilizing the Huber norm achieved a structural similarity index measure(SSIM)and a peak signal-to-noise ratio(PSNR)of 0.8378 and 30.9322,respectively,compared with the CDP *** fusion results showed that the Huber norm effectively amalgamate the features of convective and stratiform precipitation,with a reduction in the mean absolute error(MAE;16.1%and 22.6%,respectively)and root-mean-square error(RMSE;11.7%and 13.6%,respectively)compared to the 1-norm and ***,in contrast to the fusion results of scale recursive estimation(SRE),the Huber norm exhibits superior capability in capturing the localized precipitation intensity and reconstructing the detailed features of precipitation.

关键词： dual-frequency precipitation radar(DPR) dual-polarization radar data fusion regularization Huber norm

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High-precision temperature retrieval algorithm and verification for mesospheric airglow spectrum photometer

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Science China Earth Sciences 2024年第5期67卷 1639-1651页

作者： Shuqi NIU Haiyang GAO Zhaoai YAN Ke REN leilei kou Baichuan JIANG Lingbin BU Key Open Laboratory of Aerosol and Cloud Precipitation of China Meteorological Administration Nanjing 210044China School of Atmospheric Physics Nanjing University of Information Science and TechnologyNanjing 210044China National Space Science Center Chinese Academy of SciencesBeijing 100190China University of Chinese Academy of Sciences Beijing 100190China

Photometric technology,characterized by its compact structure and relatively high stability,finds wide application in measuring airglow *** instrumentation is anticipated to assume a pivotal role as the primary equipment for extensive network observations of middle and upper atmospheric temperatures in China,thereby providing crucial support for space environmental monitoring and atmospheric dynamic ***,susceptibility to various factors such as instrument inconsistency,variability in observation conditions,and alterations in the background atmospheric environment across different stations poses a challenge,potentially resulting in data inconsistencies in network *** response to these challenges,we propose a multiple-parameter iterative inversion(MPII)algorithm for temperature retrieval based on a mesospheric airglow spectrum photometer(MASP)developed by our research *** algorithm accurately identifies the center of the image circle,corrects image distortion,and thereby obtains an accurate synthetic spectrum reflective of actual *** encompasses five adjustable parameters:sky background light,atmospheric temperature,filter temperature,optical system focal length,and degree of synthetic spectrum *** to traditional methods,significant enhancements in the accuracy of the inverted temperature are *** validate the effectiveness of the MPII algorithm,we conducted combined active and passive remote sensing synchronous measurements using MASP in conjunction with a sodium fluorescence Doppler lidar developed by the National Space Science *** utilizing the lidar temperature as a reference,atmospheric background radiation is mitigated from the MASP data,and the temperature is inverted using the MPII *** analysis with the traditional method reveals that temperatures calculated by the MPII algorithm exhibit better consistency than those observed by the lidar.

关键词： Temperature inversion Airglow spectrum photometer Rotational spectral lines Sodium fluorescence Doppler lidar Comparative observations

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现行论文作者署名制度存在的问题及对策建议

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中国科技期刊研究 2020年第5期31卷 498-505页

作者：寇蕾蕾祝忠明中国科学院西北生态环境资源研究院 7430000 中国科学院大学 100049

【目的】梳理归纳现行论文作者署名制度存在的主要问题并提出相应的对策。【方法】采用网络调查法、文献调研法,从科技期刊、科研管理机构、资助机构及研究人员等视角对现行论文作者署名制度进行分析。【结果】作者署名制度存在作者身... 详细信息

【目的】梳理归纳现行论文作者署名制度存在的主要问题并提出相应的对策。【方法】采用网络调查法、文献调研法,从科技期刊、科研管理机构、资助机构及研究人员等视角对现行论文作者署名制度进行分析。【结果】作者署名制度存在作者身份标准缺乏统一性、作者贡献揭示程度低、未能涵盖所有的贡献角色等问题,可以从建立通用的作者身份标准、采用CRediT贡献分类法、与ORCID建立关联、建立健全科研评价指标体系四个方面进行补充完善。【结论】提高作者贡献的透明性和可获取性,为研究人员的职称评定、绩效考核、项目申请等提供基于具体贡献的评价指标。

关键词：作者署名作者贡献科研评价 CRediT分类法

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欧洲开放科学推进发展的体系与实践路径

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图书情报工作 2020年第10期64卷 118-127页

作者：张伶祝忠明寇蕾蕾中国科学院西北生态环境资源研究院兰州730000 中国科学院大学经济与管理学院图书情报与档案管理系北京100190 新乡医学院图书馆新乡453000

[目的/意义]探讨推动欧洲开放科学进程的动因和主要实践,找到其发展的内在逻辑、推进体系和实践路径,为我国开放科学的发展和实践提供决策参考。[方法/过程]通过网络调查法梳理欧盟从2006年推进开放获取,到近年来的开放科学实践,总结其... 详细信息

[目的/意义]探讨推动欧洲开放科学进程的动因和主要实践,找到其发展的内在逻辑、推进体系和实践路径,为我国开放科学的发展和实践提供决策参考。[方法/过程]通过网络调查法梳理欧盟从2006年推进开放获取,到近年来的开放科学实践,总结其推动开放科学发展的理念与实践。[结果/结论]欧洲开放科学发展有完善的政策体系与务实的实践路径,我国可结合国情,择优借鉴其发展经验,推动开放科学发展。

关键词：开放科学开放获取开放数据

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关联数据云图中出版类数据集特点分析

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国家图书馆学刊 2016年第1期25卷 59-68页

作者：贾君枝寇蕾蕾山西大学经济与管理学院

出版类数据集作为关联开放数据(LOD)云图中的重要数据集合,成为继社交网络类、政府类数据集之后增速最快的一类,受到了广泛关注。论文旨在通过对LOD云图中出版类数据的深入分析,从已发布的数据集、关联应用、词表使用、元数据信息等最... 详细信息

出版类数据集作为关联开放数据(LOD)云图中的重要数据集合,成为继社交网络类、政府类数据集之后增速最快的一类,受到了广泛关注。论文旨在通过对LOD云图中出版类数据的深入分析,从已发布的数据集、关联应用、词表使用、元数据信息等最佳实践角度入手,探索国外关联开放数据的服务模式,进而为我国发展关联开放数据提供参考。

关键词：出版类数据集关联开放数据

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基于改进YOLOv5的苹果采摘机器人多目标识别技术研究

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中国农机化学报 2023年第11期44卷 162-168页

作者：寇雷雷张红娜吉林工程职业学院机电工程学院吉林四平136000 内蒙古民族大学工学院内蒙古通辽028005

针对采摘机器人多目标检测影响因素多、识别准确率低等问题,为给采摘机械手提供有效的视觉引导,提出一种改进YOLOv5目标识别网络模型。首先,在YOLOv5s的基础上利用改进Ghost模块替代CSP模块,以减少模型计算量,使模型更为轻量化。考虑到... 详细信息

针对采摘机器人多目标检测影响因素多、识别准确率低等问题,为给采摘机械手提供有效的视觉引导,提出一种改进YOLOv5目标识别网络模型。首先,在YOLOv5s的基础上利用改进Ghost模块替代CSP模块,以减少模型计算量,使模型更为轻量化。考虑到预测框与目标框的横纵比问题,用CIoU_Loss替换GIoU_Loss作为损失函数,提高目标回归的稳定性。采用DSPP模块来代替原始的SPP模块进行池化操作,以解决SPP特征信息丢失问题,提高目标检测的准确性;然后,利用该模型对苹果图像样本进行训练与评价,分析模型性能的可靠性与可行性;最后,对数据集进行识别测试,并根据不同评价指标进行对比分析,验证所建模型的优越性。研究结果表明,所提出的改进YOLOv5网络模型具有识别准确性高、抗干扰能力强、检测速度快的特点。与其他模型相比,精确率最高提升8.4%,召回率最高提升5.1%,mAP最高提升10.3%。

关键词：苹果多目标识别采摘机器人神经网络

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