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A New Method for Deriving High-Vertical-Resolution Wind Vector Data from the L-Band Radar Sounding System in China

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Advances in Atmospheric Sciences 2024年第11期41卷 2192-2202页

作者： Fang YUAN Zijiang ZHOU Jie LIAO National Meteorological information {1. China Meteorological AdministrationBeijing 100081China

High-vertical-resolution radiosonde wind data are highly valuable for describing the dynamics of the meso-and microscale atmosphere. However, the current algorithm used in China's L-band radar sounding system for calculating highvertical-resolution wind vectors excessively smooths the data, resulting in significant underestimation of the calculated kinetic energy of gravity waves compared to similar products from other countries, which greatly limits the effective utilization of the data. To address this issue, this study proposes a novel method to calculate high-vertical-resolution wind vectors that utilizes the elevation angle, azimuth angle, and slant range from L-band radar. In order to obtain wind data with a stable quality, a two-step automatic quality control procedure, including the RMSE-F(root-mean-square error F) test and elemental consistency test are first applied to the slant range data, to eliminate continuous erroneous data caused by unstable signals or radar malfunctions. Then, a wind calculation scheme based on a sliding second-order polynomial fitting is utilized to derive the high-vertical-resolution radiosonde wind vectors. The evaluation results demonstrate that the wind data obtained through the proposed method show a high level of consistency with the high-resolution wind data observed using the Vaisala global Positioning System and the data observed by the new Beidou Navigation Sounding System. The calculation of the kinetic energy of gravity waves in the recalculated wind data also reaches a level comparable to the Vaisala observations.

关键词： L-band radar sounding system upper air high-vertical-resolution radiosonde wind vectors quality control polynomial fitting

Analysis of Hot Topics Regarding global Smart Elderly Care Research—1.97-2021

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China CDC weekly 2024年第9期6卷 157-161页

作者： Hongman Wang Hong Chen Yuqi Wang School of Health Humanities Peking UniversityBeijingChina center for {1. Public Health Chinese Center for Disease Control and PreventionBeijingChina

Summary What is already known about this topic?With the assistance of the internet,big data,cloud computing,and other technologies,the concept of smart elderly care has *** is added by this report?This study presents information on the countries or regions that have conducted research on smart elderly care,as well as identifies {1. hotspots and development trends in this field.

关键词： Smart internet smart

An attribute-based access control scheme using blockchain technology for IoT data protection

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High-Confidence Computing

High-Confidence Computing 2024年第3期4卷 41-50页

作者： Zenghui Yang Xiubo Chen Yunfeng He Luxi Liu Yinmei Che Xiao Wang Ke Xiao Gang Xu information Security {1. State Key Laboratory of Networking and Switching TechnologyBeijing University of Posts and TelecommunicationsBeijing 100876China information {1. of China North Industries Group Corporation Beijing 100089China School of information Science and Technology North China University of TechnologyBeijing 100144China

With the wide application of the Internet of Things(IoT),storing large amounts of IoT data and protecting data privacy has become a meaningful *** general,the access control mechanism is used to prevent illegal users from accessing private ***,traditional data access control schemes face some non-ignorable problems,such as only supporting coarse-grained access control,the risk of centralization,and high trust *** this paper,an attribute-based data access control scheme using blockchain technology is *** address these problems,attribute-based encryption(ABE)has become a promising solution for encrypted data access ***,we utilize blockchain technology to construct a decentralized access control scheme,which can grant data access with transparency and ***,our scheme also guarantees the privacy of policies and attributes on the blockchain ***,we optimize an ABE scheme,which makes the size of system parameters smaller and improves the efficiency of *** optimizations enable our proposed scheme supports large attribute universe requirements in IoT ***,to prohibit attribute impersonation and attribute replay attacks,we design a challenge-response mechanism to verify the ownership of ***,we evaluate the security and performance of the *** comparisons with other related schemes show the advantages of our proposed *** to existing schemes,our scheme has more comprehensive advantages,such as supporting a large universe,full security,expressive policy,and policy hiding.

关键词： Attribute-based encryption Access control Blockchain IoT data protection

Low-Complexity Reconstruction of Covariance Matrix in Hybrid Uniform Circular Array

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China Communications 2024年第3期21卷 66-74页

作者： Fu Zihao Liu Yinsheng Duan Hongtao information School Communication University of ChinaBeijing 100024China beijing Institute of Electronic System Engineering Beijing 100854China School of Electronic and information Engineering Beijing Jiaotong UniversityBeijing 100044China beijing Radio Monitoring Station of State Radio Monitoring {1.(SRMC) Beijing 100037China

Spatial covariance matrix(SCM) is essential in many multi-antenna systems such as massive multiple-input multiple-output(MIMO). For multi-antenna systems operating at millimeter-wave bands, hybrid analog-digital structure has been widely adopted to reduce the cost of radio frequency *** this situation, signals received at the antennas are unavailable to the digital receiver, and as a consequence, traditional sample average approach cannot be used for SCM reconstruction in hybrid multi-antenna systems. To address this issue, beam sweeping algorithm(BSA) which can reconstruct the SCM effectively for a hybrid uniform linear array, has been proposed in our previous works. However, direct extension of BSA to a hybrid uniform circular array(UCA)will result in a huge computational burden. To this end, a low-complexity approach is proposed in this paper. By exploiting the symmetry features of SCM for the UCA, the number of unknowns can be reduced significantly and thus the complexity of reconstruction can be saved accordingly. Furthermore, an insightful analysis is also presented in this paper, showing that the reduction of the number of unknowns can also improve the accuracy of the reconstructed SCM. Simulation results are also shown to demonstrate the proposed approach.

关键词： hybrid array millimeter-wave spatial covariance matrix uniform circular array

Review of the detasseling techniques for maize(Zea mays L.)hybrid seed production

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International Journal of Agricultural and Biological Engineering 2024年第3期17卷 1-11页

作者： Ruirui Zhang Jiaxuan Yang Liping Chen Chenchen Ding Longlong Li Linhuan Zhang National Research center of Intelligent Equipment for Agriculture Beijing Academy of Agriculture and Forestry SciencesBeijing 100097China National center of International Research on Agricultural Aerial {1. Technology Beijing 100097China Research center of Intelligent Equipment Beijing Academy of Agriculture and Forestry SciencesBeijing 100097China

Maize(Zea mays L.)is a critical staple crop globally,integral to human consumption,food security,and agricultural product *** quality and purity of maize seeds,essential for hybrid seed production,are contingent upon effective *** study investigates the evolution of detasseling technologies and their {1. in Chinese maize hybrid seed production,with a comparative analysis against the United States.A comprehensive examination of the development and utilization of detasseling technology in Chinese maize hybrid seed production was undertaken,with a specific focus on key *** from the United States were included for comparative *** analysis encompassed various detasseling methods,including manual,semi-mechanized,and cytoplasmic male sterility,as well as more recent innovations such as detasseling machines,and the emerging field of intelligent detasseling driven by unmanned aerial vehicles(UAVs),computer vision,and mechanical *** detasseling methods were predominantly employed by *** the challenges of inflexible and occasionally overlooked,applying detasseling machines is efficient and *** present,China’s detasseling operations in hybrid maize seed production are mainly carried out by manual work,which is labor-intensive and *** order to address this issue,China is dedicated to developing intelligent detasseling *** study emphasizes the critical role of detasseling in hybrid maize seed *** United States has embraced mechanized *** {1. and development of manual and mechanized detasseling were applied later than those in the United States,but latest intelligent detasseling technologies first appeared in *** detasseling is expected to be the future direction,ensuring the quality and efficiency of hybrid maize seed production,with implications for global food security.

关键词： detasseling technique detasseling machine UAVs intelligent agriculture maize hybrid seed production

Advances and outlook of integrated reservoir-wellbore-pipe network simulation technology

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Energy Geoscience

Energy Geoscience 2024年第4期5卷 1-7页

作者： Hongmin Yu Youqi Wang Chuanjie Cheng Quanqi Dai Jingjing Sun Qingxin Zhang SINOPEC Petroleum Exploration and Production Research Institute Beijing102206China Research and development {1. for the Sustainable development of Continental Sandstone Mature Oilfield National Energy AdministrationBeijing102206China

The integrated simulation and optimization technology of reservoir-wellbore-pipe network is developed to reflect the mutual influence and restriction among reservoir engineering,oil production engineering and surface engineering,and to obtain the scheme with minimum conflict and optimal benefit in each *** technology is based on the concept of global optimization to maximize production and profit,reduce costs and increase *** paper elaborates the current situation of integrated simulation technology of reservoir-wellbore-pipe network both at home and abroad,discusses its correlation with the primary business of Sinopec and its {1. from three aspects of modeling,cloud platform and *** on its future {1. are put forward from underlying data,software platform,popularization and application,and cross-border integration to provide means and guidance for the construction of intelligent oil and gas *** results show that the integrated simulation of reservoir-wellbore-pipe network can better reflect the optimization requirements of each step,avoid the ineffective operation of field equipment,and effectively improve the efficiency of research and *** solution,global optimization method and pressure fitting,which can make the simulation results reflect the real situation,are the key technologies for the *** theoretical technology and main function research of integrated simulation technology have been mature,but the large-scale application and local function improvement of oil and gas fields are yet to be *** the future,the integrated simulation of reservoir-wellbore-pipe network will develop from digitalization to modeling and intellectualization,from local simulation to cloud computing,and from manual intervention to intelligent *** suggest speeding up the construction of the unified database and model base of the whole underlying platform,strengthening the constr

关键词： Reservoir-wellbore-pipe network Integrated production modelling Prospect development suggestion Simulation

On the use of explainable AI for susceptibility modeling:Examining the spatial pattern of SHAP values

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Geoscience Frontiers 2024年第4期15卷 14-27页

作者： Nan Wang Hongyan Zhang Ashok Dahal Weiming Cheng Min Zhao Luigi Lombardo Key Laboratory of Geographical Processes and Ecological Security in Changbai Mountains Ministry of EducationSchool of Geographical SciencesNortheast Normal UniversityChangchun 130024China State Key Laboratory of Resources and Environmental information Systems Institute of Geographic Sciences and Natural Resources ResearchChinese Academy of SciencesBeijing 100101China University of Twente Faculty of Geo-Information Science and Earth Observation(ITC)PO Box 217EnschedeAE 7500Netherlands University of Chinese Academy of Sciences Beijing 100049China Jiangsu center for Collaborative Innovation in Geographic {1. Resource development and application Nanjing 210023China Collaborative Innovation center of South China Sea Studies Nanjing 210093China State Key Laboratory of Earth Surface Processes and Resource Ecology Beijing Normal UniversityBeijing 100875China Key Laboratory of Environmental Change and Natural Disaster Beijing Normal UniversityBeijing 100875China center for Geodata and Analysis Faculty of Geographical ScienceBeijing Normal UniversityBeijing 100875China

Hydro-morphological processes(HMP,any natural phenomenon contained within the spectrum defined between debris flows and flash floods)are globally occurring natural hazards which pose great threats to our society,leading to fatalities and economical *** this reason,understanding the dynamics behind HMPs is needed to aid in hazard and risk *** this work,we take advantage of an explainable deep learning model to extract global and local interpretations of the HMP occurrences across the whole Chinese *** use a deep neural network architecture and interpret the model results through the spatial pattern of SHAP *** doing so,we can understand the model prediction on a hierarchical basis,looking at how the predictor set controls the overall susceptibility as well as doing the same at the level of the single mapping *** model accurately predicts HMP occurrences with AUC values measured in a ten-fold cross-validation ranging between 0.83 and *** level of predictive performance attests for an excellent prediction *** main difference with respect to traditional statistical tools is that the latter usually lead to a clear interpretation at the expense of high performance,which is otherwise reached via machine/deep learning solutions,though at the expense of *** recent development of explainable Al is the key to combine both *** this work,we explore this combination in the context of HMP susceptibility ***,we demonstrate the extent to which one can enter a new level of data-driven interpretation,supporting the decision-making process behind disaster risk mitigation and prevention actions.

关键词： Hydro-morphological processes SHAP maps Explainable AI China

A Framework Based on the DAO and NFT in Blockchain for Electronic Document Sharing

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Computer Modeling in Engineering & Sciences 2024年第9期140卷 2373-2395页

作者： Lin Chen Jiaming Zhu Yuting Xu Huanqin Zheng Shen Su Cyberspace Institute of Advanced Technology Guangzhou UniversityGuangzhou510006China Engineering Research center of lntegration and {1. of Digital Learning Technology Ministry of EducationBeijing100816China

In the information age,electronic documents(e-documents)have become a popular alternative to paper documents due to their lower costs,higher dissemination rates,and ease of knowledge ***,digital copyright infringements occur frequently due to the ease of copying,which not only infringes on the rights of creators but also weakens their creative ***,it is crucial to establish an e-document sharing system that enforces copyright ***,the existing centralized system has outstanding vulnerabilities,and the plagiarism detection algorithm used cannot fully detect the context,semantics,style,and other factors of the *** watermark technology is only used as a means of infringement *** paper proposes a decentralized framework for e-document sharing based on decentralized autonomous organization(DAO)and non-fungible token(NFT)in *** use of blockchain as a distributed credit base resolves the vulnerabilities inherent in traditional centralized *** e-document evaluation and plagiarism detection mechanisms based on the DAO model effectively address challenges in comprehensive text information checks,thereby promoting the enhancement of e-document *** mechanism for protecting and circulating e-document copyrights using NFT technology ensures effective safeguarding of users’e-document copyrights and facilitates e-document ***,recognizing the security issues within the DAO governance mechanism,we introduce an innovative optimization *** experimentation,we validate the enhanced security of the optimized governance mechanism,reducing manipulation risks by up to 51..Additionally,by utilizing evolutionary game analysis to deduce the equilibrium strategies of the framework,we discovered that adjusting the reward and penalty parameters of the incentive mechanism motivates creators to generate superior quality and unique e-documents,while evaluators are more likely to engage in

关键词： Electronic document sharing blockchain DAO NFT evolutionary game

SDGSAT-1. Capabilities for Monitoring and Evaluating SDG Indicators

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空间科学学报 2024年第4期44卷 677-686页

作者： GUO Huadong DOU Changyong LIANG Dong JIANG Nijun TANG Yunwei MA Wenyong International Research center for Big Data for Sustainable {1. Beijing 100094 Key Laboratory of Digital Earth Science Aerospace Information Research InstituteChinese Academy of SciencesBeijing 100094 University of Chinese Academy of Sciences Beijing 100049

SDGSAT-1.the world's first science satellite dedicated to assisting the United Nations 2030 Sustainable development Agenda,has been operational for over two and a half *** provides valuable data to aid in implementing the Sustainable development Goals *** its Open Science Program,the satellite has maintained consistent operations and delivered free data to scientific and technological users from 88 *** program has produced a wealth of scientific output,with 72 papers,including 28 on data processing methods and 44 on applications for monitoring progress toward SDGs related to sustainable cities,clean energy,life underwater,climate action,and clean water and ***-1.is equipped with three key instruments:a multispectral imager,a thermal infrared spectrometer,and a glimmer imager,which have enabled ground-breaking research in a variety of domains such as water quality analysis,identification of industrial heat sources,assessment of environmental disaster impacts,and detection of forest *** precise measurements and ongoing monitoring made possible by this invaluable data significantly advance our understanding of various environmental *** are essential for making well-informed decisions on a local and global *** its application to academic research,SDGSAT-1.promotes global cooperation and strengthens developing countries'capacity to accomplish their sustainable development *** the satellite continues to gather and distribute data,it plays a pivotal role in developing strategies for environmental protection,disaster management and relief,and resource *** initiatives highlight the satellite's vital role in fostering international collaboration and technical innovation to advance scientific knowledge and promote a sustainable future.

关键词： SDGSAT-1 Earth observation Remote sensing SDGs