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Multi-channel radar array design method and algorithm

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science china(Information sciences) 2010年第7期53卷 1470-1480页

作者： su yi1*, zhu yutao1, YU WenXian2, xu hongbo1 & LEI WenTai1 1school of electronic science and engineering, national university of defense technology, changsha 410073, china 2school of Electric, Information and Electrical engineering, Shanghai Jiao Tong university, Shanghai 200240, china 1. school of electronic science and engineering National University of Defense Technology Changsha 410073 China2. School of Electric Information and Electrical Engineering Shanghai Jiao Tong University Shanghai 200240 China

The array design of radar antenna is no more a new problem at all. Nevertheless, the array design of multi-channel radar, especially that of MIMO (multiple-input multiple-output) radar, is a new problem. The performance of space diversion and spatial sampling of target scattering are dependent on the array design of MIMO radar, and consequently, which in turn will determine the performances of target parameter estimation, DOA, and imaging. In this paper, commencing with target scattering model, T/R signal model of MIMO radar, and spatial sampling ability for this system are analyzed. Conceptually, under the far field condition, spatial convolution principle determines the array design theory. Based on this idea, array design method and also algorithm are proposed in this paper.

关键词： MIMO-radar antenna arrays DOA estimation spatial sampling imaging algorithm

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基于异构图和关键词的抽取式文本摘要模型

电子科技大学学报 2024年第2期53卷 259-270页

作者：朱颀林王羽徐建南京理工大学计算机科学与工程学院南京210094 国防科技大学信息系统工程重点实验室长沙410003 中国电子科技集团公司第二十八研究所南京210007

抽取式文本摘要使用一定的策略从冗长的文本中选择一些句子组成摘要,其关键在于要尽可能多地利用文本的语义信息和结构信息。为了更好地挖掘这些信息,进而利用它们指导摘要的抽取,提出了一种基于异构图和关键词的抽取式文本摘要模型(HGK... 详细信息

抽取式文本摘要使用一定的策略从冗长的文本中选择一些句子组成摘要,其关键在于要尽可能多地利用文本的语义信息和结构信息。为了更好地挖掘这些信息,进而利用它们指导摘要的抽取,提出了一种基于异构图和关键词的抽取式文本摘要模型(HGKsum)。该模型首先将文本建模为由句子节点和词语节点构成的异构图,在异构图上使用图注意力网络学习节点的特征,之后将关键词抽取任务作为文本摘要任务的辅助任务,使用多任务学习的方式进行训练,得到候选摘要,最后对候选摘要进行精炼以降低冗余度,得到最终摘要。在基准数据集上的对比实验表明,该模型性能优于基准模型,此外,消融实验也证明了引入异构节点和关键词的必要性。

关键词：抽取式文本摘要异构图关键词图注意力网络多任务学习

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Comparison of Short-term Stability Estimation Methods of GNSS On-board Clock

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Comparison of Short-term Stability Estimation Methods of GNS...

Deep Learning-Based Prediction of Traffic Accidents Risk for Internet of Vehicles

第三届中国卫星导航学术年会

作者： GONG Hang* 1 ,YANG Wenke 1 ,wang Yong 1 ,zhu Xiangwei 1 ,wang Feixue 1 1.Satellite Navigation R&D Center,school of electronic science and engineering,national university of defense technology,changsha,Hunan 410073,china

The short-term frequency stability of satellite on-board clock is of great significance for GNSS applications,such as satellite clock modeling,simulation and clock offset *** this paper,four short-term frequency stability esti-mation methods are analyzed,which need observation data from only one station in contrast with ODTS needing continuous observation of large ground monitoring *** and accuracy of all these four methods is analyzed and compared using GPS and COMPASS observation data,and their advantage and disadvantage are discussed *** COMPASS and Galileo systems which are currently in the early stage of construction,this paper proposes some meaningful suggestions of on-board clock short-term frequency stability estima-tion.

关键词： GNSS On-board Clock Short-term Stability Estimation Precise Ephemeris Broadcast Ephemeris Smoothed Carrier Phase COMPASS ODTS (Orbit Determination and Time Synchronization)

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china Communications 2022年第2期19卷 214-224页

作者： Haitao Zhao Xiaoqing Li Huiling Cheng Jun Zhang Qin wang hongbo zhu school of Communication and Information engineering Nanjing University of Posts and TelecommunicationsNanjing 210003China school of electronic and Information engineering The Hong Kong Polytechnic UniversityHong KongChina

With the increasing number of vehicles,traffic accidents pose a great threat to human ***,aiming at reducing the occurrence of traffic accidents,this paper proposes an algorithm based on a deep convolutional neural network and a random forest to predict accident ***,the proposed algorithm includes a feature extractor and a feature classifier,where the former extracts key features using a convolutional neural network and the latter outputs a probability value of traffic accidents using a random forest with multiple decision trees,which indicates the degree of accident *** show that the proposed algorithm can achieve higher performance in terms of the Area Under the Curve(AUC)of the Receiver Characteristic Operator as well as accuracy than the existing algorithms based on the Adaboost or the pure convolutional neural networks.

关键词： road safety risk prediction Internet of Vehicles

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Achieving a high energy storage density in Ag(Nb,Ta)O_(3) antiferroelectric films via nanograin engineering

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Journal of Advanced Ceramics 2023年第1期12卷 196-206页

作者： hongbo CHENG Xiao ZHAI Jun OUYANG Limei ZHENG Nengneng LUO Jinpeng LIU Hanfei zhu yingying wang Lanxia HAO Kun wang Institute of Advanced Energy Materials and Chemistry School of Chemistry and Chemical EngineeringQilu University of Technology(Shandong Academy of Sciences)Jinan 250353China College of electronic and Optical engineering Nanjing University of Posts and TelecommunicationsNanjing 210023China school of Physics Shandong UniversityJinan 250100China Guangxi Key Laboratory of Processing for Non-ferrous Metallic and Featured Materials School of ResourcesEnvironment and MaterialsCenter on Nanoenergy ResearchSchool of Physical Science and TechnologyGuangxi UniversityNanning 530004China Key Laboratory for Liquid-Solid Structure Evolution and Processing of Materials(Ministry of Education) School of Materials Science and EngineeringShandong UniversityJinan 250061China Jinan Cigarette Factory China Tobacco Shandong Industrial Co.Ltd.Jinan 250104China

Due to its lead-free composition and a unique double polarization hysteresis loop with a large maximum polarization(Pmax)and a small remnant polarization(Pr),AgNbO_(3)-based antiferroelectrics(AFEs)have attracted extensive research interest for electric energy storage ***,a low dielectric breakdown field(Eb)limits an energy density and its further *** this work,a highly efficient method was proposed to fabricate high-energy-density Ag(Nb,Ta)O_(3) capacitor films on Si substrates,using a two-step process combining radio frequency(RF)-magnetron sputtering at 450℃and post-deposition rapid thermal annealing(RTA).The RTA process at 700℃led to sufficient crystallization of nanograins in the film,hindering their lateral growth by employing short annealing time of 5 *** obtained Ag(Nb,Ta)O_(3) films showed an average grain size(D)of~14 nm(obtained by Debye-Scherrer formula)and a slender room temperature(RT)polarization-electric field(P-E)loop(Pr≈3.8 mC·cm^(−2) and P_(max)≈38 mC·cm^(−2) under an electric field of~3.3 MV·cm^(−1)),the P-E loop corresponding to a high recoverable energy density(W_(rec))of~46.4 J·cm^(−3) and an energy efficiency(η)of~80.3%.Additionally,by analyzing temperature-dependent dielectric property of the film,a significant downshift of the diffused phase transition temperature(T_(M2-M3))was revealed,which indicated the existence of a stable relaxor-like AFE phase near the *** downshift of the T_(M2-M3) could be attributed to a nanograin size and residual tensile strain of the film,and it led to excellent temperature stability(20-240℃)of the energy storage performance of the *** results indicate that the Ag(Nb,Ta)O_(3) film is a promising candidate for electrical energy storage applications.

关键词： antiferroelectrics(AFE) AgNbO_(3) Ag(Nb Ta)O_(3) energy storage film capacitors nanograin engineering

Synergically improved energy storage performance and stability in sol–gel processed BaTiO_(3)/(Pb,La,Ca)TiO_(3)/BaTiO_(3) tri-layer films with a crystalline engineered sandwich structure

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Journal of Advanced Ceramics 2023年第12期12卷 2300-2314页

作者： Jinpeng Liu ying wang Hanfei zhu Hongyu Luo Xiao Zhai Yu Huan Jing Yan Kun wang Chao Liu hongbo Cheng Jun Ouyang school of Chemistry and Chemical engineering Qilu University of Technology(Shandong Academy of Sciences)Jinan 250353China school of Physics Shandong UniversityJinan 250100China school of Material science and engineering University of JinanJinan 250022China College of Physics and electronic engineering Qilu Normal UniversityJinan 250200China china Tobacco Shandong Industrial Co. Ltd.Jinan 250014China Key Laboratory of Key Film Materials&Application for Equipments(Hunan Province) Hunan Provincial Key Laboratory of Thin Film Materials and DevicesSchool of Material Sciences and EngineeringXiangtan UniversityXiangtan 411105China

Achieving an excellent energy storage performance,together with high cycling reliability,is desirable for expanding technological applications of ferroelectric ***,in well-crystallized ferroelectric materials,the concomitant high polarizability and low polarization saturation field have led to a square-shaped polarization–electric field loop,fatally impairing both recoverable energy density(W_(rec))and efficiency(η).Nanocrystalline ferroelectric films with a macroscopically amorphous structure have shown an improved W_(rec) andη,but their much lower polarizability demands an extremely high electric field to achieve such performances,which is undesirable from an economic ***,we propose a strategy to boost the energy storage performances and stability of ferroelectric capacitors simultaneously by constructing a tri-layer film in which a well-crystallized ferroelectric layer was sandwiched by two pseudo-linear dielectric layers with a dominant amorphous *** sol–gel-derived BaTiO_(3)/(Pb,La,Ca)TiO_(3)/BaTiO_(3)(BTO/PLCT/BTO)tri-layer films,we show that the above design is realized via rapid thermal annealing which fully crystallized the middle PLCT layer while left the top/bottom BTO cap layers in a poor crystallization *** sandwiched structure is endowed with an enhanced maximum polarization while a small remnant one and a much-delayed polarization saturation,which corresponds to large W_(rec)≈80 J/cm^(3) and highη≈86%.Furthermore,the film showed an outstanding cycling stability:its W_(rec) andηremain essentially unchanged after 10^(9) electric cycles(DW/W<4%,Dη/η<2%).These good energy storage characteristics have proved the effectiveness of our proposed strategy,paving a way for the utilization of sandwiched films in applications of electric power systems and advanced pulsed-discharge devices.

关键词： energy storage sandwich film amorphous structure nanocrystal cluster stability

CEPC Technical Design Report

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Radiation Detection technology and Methods 2024年第1期8卷 I0003-I0016,1-1091页

作者： Waleed Abdallah Tiago Carlos Adorno de Freitas Konstantin Afanaciev Shakeel Ahmad Ijaz Ahmed Xiaocong Ai Abid Aleem Wolfgang Altmannshofer Fabio Alves Weiming An Rui An Daniele Paolo Anderle Stefan Antusch Yasuo Arai Andrej Arbuzov Abdesslam Arhrib Mustafa Ashry Sha Bai Yu Bai Yang Bai Vipul Bairathi Csaba Balazs Philip Bambade Yong Ban Tripamo Bandyopadhyay Shou-Shan Bao Desmond P.Barber Ayse Bat Varvara Batozskaya subash Chandra Behera Alexander Belyaev Michele Bertucci Xiao-Jun Bi Yuanjie Bi Tianjian Bian Fabrizio Bianchi Thomas Biekotter Michela Biglietti Shalva Bilanishvili Deng Binglin Denis Bodrov Anton Bogomyagkov Serge Bondarenko Stewart Boogert Maarten Boonekamp Marcello Borri Angelo Bosotti Vincent Boudry Mohammed Boukidi Igor Boyko Ivanka Bozovic Giuseppe Bozzi Jean-Claude Brient Anastasiia Budzinskaya Masroor Bukhari Vladimir Bytev Giacomo Cacciapaglia Hua Cai Wenyong Cai Wujun Cai yijian Cai yizhou Cai Yuchen Cai Haiying Cai Huacheng Cai Lorenzo Calibbi Junsong Cang Guofu Cao Jianshe Cao Antoine Chance xuejun Chang Yue Chang Zhe Chang Xinyuan Chang Wei Chao Auttakit Chatrabhuti yimin Che Yuzhi Che Bin Chen Danping Chen Fuqing Chen Fusan Chen Gang Chen Guoming Chen Hua-Xing Chen Huirun Chen Jinhui Chen Ji-Yuan Chen Kai Chen Mali Chen Mingjun Chen Mingshui Chen Ning Chen Shanhong Chen Shanzhen Chen Shao-Long Chen Shaomin Chen Shiqiang Chen Tianlu Chen Wei Chen Xiang Chen Xiaoyu Chen Xin Chen xun Chen xurong Chen Ye Chen ying Chen Yukai Chen Zelin Chen Zilin Chen Gang Chen Boping Chen Chunhui Chen Hok Chuen Cheng Huajie Cheng Shan Cheng Tongguang Cheng Yunlong Chi Pietro Chimenti Wen Han Chiu Guk Cho Ming-Chung Chu Xiaotong Chu Ziliang Chu Guglielmo Coloretti Andreas Crivellin Hanhua Cui Xiaohao Cui Zhaoyuan Cui Brunella D'Anzi Ling-Yun Dai Xinchen Dai xuwen Dai Antonio De Maria Nicola De Filippis Christophe De La Taille Francesca De Mori Chiara De Sio Elisa Del Core Shuangxue Deng Wei-Tian Deng Zhi Deng Ziyan Deng Bhupal Dev Tang Dewen Biagio Di Micco Ran Ding Siqin Dingl Yadong Ding Haiyi Dong Jianin AGH university of science and technology Faculty of Physics and Applied Computer ScienceKrakow Anhui university HefeiAnhui Applied Physics Department Federal Urdu University of ArtsScience and TechnologyIslamabad Banaras Hindu university Institute of ScienceVaranasi Bandirma Onyedi Eylul university Bandirma Beihang university Beijing Beijing Computational science Research Center Beijing Beijing Conveyi LTD Beijing Beijing Glass Research Institute Co. LtdBeijing Beijing Institute of technology Beijing Beijing Normal university Beijing Brown university ProvidenceRI Budker Institute of Nuclear Physics Novosibirsk Cadi Ayyad university Laboratory of Fundamental and Applied PhysicsPolydisciplinary FacultyMarrakech Cairo university Giza Center for Theory and Computation National Tsing Hua UniversityHsinchu Central china Normal university WuhanHubei Central South university ChangshaHunan Centro de Fisica Teorica de Particulas Universidade Tecnica de LisboaLisboa Chengdu KaitengSifang Digital Radio&TV Equipment Co. LtdChengduSichuan china academy of engineering physics MianyangSichuan china building materials academy Beijing china Center of Advanced science and technology Beijing china Institute of Atomic Energy Beijing china Jiliang university HangzhouZhejiang china Nuclear Instrument CO. LTDBeijing china university of Geosciences Beijing china university of Geosciences WuhanHubei china university of Mining and technology XuzhouJiangsu china West Normal university NanchongSichuan Chongqing university Department of PhysicsChongqing Chulalongkorn university Bangkok City university of Hong Kong Department of PhysicsHong Kong Cockcroft Institute Daresbury Cornell university IthacaNY CPPM(AMU/IPhU&CNRS/INP) Marseille Dalian Minzu university DalianLiaoning Dalian university of technology Department of PhysicsDalian Deutsches Elektronen-Synchrotron DESY Hamburg Dzhelepov Laboratory of Nuclear Problems of Joint Institute for Nuclear Research(DLNP JINR) Dubna East china university Of science And Technol

The Circular Electron Positron Collider(CEPC)is a large scientific project initiated and hosted by china,fostered through extensive collaboration with international *** complex comprises four accelerators:a 30 GeV Linac,a 1.1 GeV Damping Ring,a Booster capable of achieving energies up to 180 GeV,and a Collider operating at varying energy modes(Z,W,H,and tt).The Linac and Damping Ring are situated on the surface,while the subterranean Booster and Collider are housed in a 100 km circumference underground tunnel,strategically accommodating future expansion with provisions for a potential super Proton Proton Collider(SPPC).The CEPC primarily serves as a Higgs *** its baseline design with synchrotron radiation(SR)power of 30 MW per beam,it can achieve a luminosity of 5×10^(34)cm^(-2)s^(-1)per interaction point(IP),resulting in an integrated luminosity of 13 ab^(-1)for two IPs over a decade,producing 2.6 million Higgs *** the SR power to 50 MW per beam expands the CEPC's capability to generate 4.3 million Higgs bosons,facilitating precise measurements of Higgs coupling at sub-percent levels,exceeding the precision expected from the HL-LHC by an order of *** Technical Design Report(TDR)follows the Preliminary Conceptual Design Report(Pre-CDR,2015)and the Conceptual Design Report(CDR,2018),comprehensively detailing the machine's layout,performance metrics,physical design and analysis,technical systems design,R&D and prototyping efforts,and associated civil engineering ***,it includes a cost estimate and a preliminary construction timeline,establishing a framework for forthcoming engineering design phase and site selection *** is anticipated to begin around 2027-2028,pending government approval,with an estimated duration of 8 *** commencement of experiments and data collection could potentially be initiated in the mid-2030s.

关键词： initiated exceeding precise

Analysis of electromagnetic pulses generation from laser coupling with polymer targets: Effect of metal content in target

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Matter and Radiation at Extremes 2020年第1期5卷 1-7页

作者： Yadong Xia Feng Zhang hongbo Cai Weimin Zhou Chao Tian Bo Zhang Dongxiao Liu Tao yi yilin xu Feng wang Tingshuai Li Shaoping zhu school of Materials and Energy University of Electronic Science and Technology of ChinaChengdu 611731People’s Republic of China Laser Fusion Research Center China Academy of Engineering PhysicsMianyang 621900People’s Republic of China science and technology on Plasma Physics Laboratory Laser Fusion Research CenterChina Academy of Engineering PhysicsMianyang 621900People’s Republic of China Institute of Applied Physics and Computational Mathematics Beijing100094People’s Republic of China HEDPS Center for Applied Physics and TechnologyPeking UniversityBeijing 100871People’s Republic of China IFSA Collaborative Innovation Center Shanghai Jiao Tong UniversityShanghai 200240People’s Republic of China Graduate school China Academy of Engineering PhysicsP.O.Box 2101Beijing 100088People’s Republic of China

Powerful lasers interacting with solid targets can generate intense electromagnetic pulses(EMPs).In this study,EMPs produced by a pulsed laser(1 ps,100 J)shooting at CH targets doped with different titanium(Ti)contents at the XG-III laser facility are measured and *** results demonstrate that the intensity of EMPs first increases with Ti doping content from 1%to 7%and then *** electron spectra show that EMP emission is closely related to the hot electrons ejected from the target surface,which is confirmed by an analysis based on the target–holder–ground equivalent antenna *** conclusions of this study provide a new approach to achieve tunable EMP radiation by adjusting the metal content of solid targets,and will also help in understanding the mechanism ofEMPgeneration and ejection of hot electrons during laser coupling with targets.

关键词： antenna coupling titanium

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一种面向多RIS的LMMSE信道估计方法

无线电工程 2024年第11期54卷 2657-2663页

作者：朱鹏博朱勇刚安康王浩南京信息工程大学电子与信息工程学院江苏南京210044 国防科技大学第六十三研究所江苏南京210007

在智能超表面(Reconfigurable Intelligent surface,RIS)辅助的无线通信系统中,信道状态信息(Channel Situation Information,CSI)是RIS反射相位矩阵优化的前提和基础。为了获得精准的CSI,针对多RIS辅助的多输入单输出(Multiple Input Single Output,MISO)通信系统,提出了一种训练序列优化和线性最小均方误差(Linear Minimum Mean Squared Error,LMMSE)方法相结合的信道估计方法。该方法使用LMMSE方法估计级联信道的CSI;在所得CSI的基础上,对RIS的反射矩阵和基站(Base Station,BS)发射的训练序列进行了联合优化,最小化原本信道估计的均方误差(Mean Squared Error,MSE),进一步提高了信道估计的精度。仿真结果验证了所提信道估计方法和双RIS联合训练反射矩阵与训练序列优化设计的有效性。与各种基准方法进行比较,具有更高的CSI估计精度。

关键词：多智能超表面信道估计训练反射矩阵优化训练序列优化线性最小均方误差