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Real-time object tracking via least squares transformation in spatial and Fourier domains for unmanned aerial vehicles

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Chinese Journal of Aeronautics 2019年第7期32卷 1716-1726页

作者： xiaoyuan yang Ridong ZHU Jingkai WANG Zhengze li School of Mathematics and Systems Science Beihang University

This paper addresses the problem of real-time object tracking for unmanned aerial vehicles. We consider the task of object tracking as a classification problem. Training a good classifier always needs a huge number of samples, which is always time-consuming and not suitable for realtime applications. In this paper, we transform the large-scale least-squares problem in the spatial domain to a series of small-scale least-squares problems with constraints in the Fourier domain using the correlation filter technique. Then, this problem is efficiently solved by two stages. In the first stage, a fast method based on recursive least squares is used to solve the correlation filter problem without constraints in the Fourier domain. In the second stage, a weight matrix is constructed to prune the solution attained in the first stage to approach the constraints in the spatial domain. Then, the pruned classifier is used for tracking. To evaluate proposed tracker’s performance, comprehensive experiments are conducted on challenging aerial sequences in the UAV123 dataset. Experimental results demonstrate that proposed approach achieves a state-ofthe-art tracking performance in aerial sequences and operates at a mean speed of beyond 40 frames/s. For further analysis of proposed tracker’s robustness, extensive experiments are also performed on recent benchmarks OTB50, OTB100, and VOT2016.

关键词： Correlation filter Discrete Fourier transform Least squares Object tracking Unmanned aerial vehicle

融合相似预报方法在陇东南短期强降水预报中的应用

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高原气象 2025年第1期44卷 214-223页

作者：黄晓远李旭杜梦莹叶培龙李艳兰州大学大气科学学院甘肃兰州730000 兰州中心气象台甘肃兰州730020

基于逐步过滤相似法和自组织映射(SOM)神经网络方法,提出了一种融合相似预报方法。利用ECMWF模式预报产品、ERA5再分析资料和地面气象台站观测数据,使用该方法对2021-2022年陇东南地区开展了时效为72 h的强降水预报试验,并对预报效果进... 详细信息

基于逐步过滤相似法和自组织映射(SOM)神经网络方法,提出了一种融合相似预报方法。利用ECMWF模式预报产品、ERA5再分析资料和地面气象台站观测数据,使用该方法对2021-2022年陇东南地区开展了时效为72 h的强降水预报试验,并对预报效果进行了检验。结果表明:(1)融合相似预报方法的TS评分处于4.5%~9.1%之间,与ECMWF模式预报结果相比表现出一定的优势。随着预报时效的增长,强降水预报的TS评分呈现减小的趋势,其在08:00(北京时,下同)起报的TS评分相对较高。(2)相比于单独使用逐步过滤相似预报,融合相似预报方法的准确性有所提升,并能在一定程度上降低空报率。其中08:00起报和20:00起报的TS评分提高了1.31%和0.63%,而FAR同时下降了2.39%和1.25%。

关键词：强降水短期预报相似预报逐步过滤相似自组织映射(SOM)

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FULL-DISCRETE FINITE ELEMENT METHOD FOR STOCHASTIC HYPERBOliC EQUATION

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Journal of Computational Mathematics 2015年第5期33卷 533-556页

作者： xiaoyuan yang Xiaocui li Ruisheng Qi Yinghan Zhang Department of Mathematics Beihang UniversityLMIB of the Ministry of Education Beijing 100191 China Department of Mathematics Northeastern University at Qinhuangdao China

This paper is concerned with the finite element method for the stochastic wave equation and the stochastic elastic equation driven by space-time white noise. For simplicity~ we rewrite the two types of stochastic hyperbolic equations into a unified form. We convert the stochastic hyperbolic equation into a regularized equation by discretizing the white noise and then consider the full-discrete finite element method for the regularized equation. We derive the modeling error by using “Green＇s method” and the finite element approximation error by using the error estimates of the deterministic equation. Some numerical examples are presented to verify the theoretical results.

关键词： Stochastic hyperbolic equation Strong convergence Additive noise Wiener process.

The roles of different gene expression regulators in acoustic variation in the intermediate horseshoe bat revealed by long-read and short-read RNA sequencing data

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Current Zoology 2024年第5期70卷 575-588页

作者： Qianqian li Jianyu Wu xiuguang Mao School of Ecological and Environmental Sciences East China Normal UniversityShanghai 200062China

Gene expression changes contribute greatly to phenotypic variations in *** patterns of regulators of gene expression is important to fully understand the molecular mechanism underlying phenotypic *** horseshoe bats,the cochleae are fnely tuned to echoes of call ***,using 2 recently diverged subspecies of the intermediate horseshoe bat(Rhinolophus affnis hainanus and ***)with great acoustic variations as the system,we aim to explore relative roles of different regulators of gene expression(differential gene expression,alternative splicing(AS)and long non-coding RNAs(lncRNAs))in phenotypic variation with a combination of Illumina short-read and Nanopore long-read RNA-seq data from the *** to ***,*** exhibited much more upregulated differentially expressed genes(DEGs)and multiple of them may play important roles in the maintenance and damage repair of auditory hair *** identifed 411 differentially expressed lncRNAs and their target DEGs upregulated in *** were also mainly involved in a protective mechanism for auditory hair *** 3 different methods of AS analysis,we identifed several candidate alternatively spliced genes(ASGs)that expressed different isoforms which may be associated with acoustic divergence of the 2 *** observed signifcantly less overlap than expected between DEGs and ASGs,supporting complementary roles of differential gene expression and AS in generating phenotypic ***,our study highlights the importance of a combination of short-read and long-read RNA-seq data in examining the regulation of gene expression changes responsible for phenotypic variations.

关键词： alternative splicing lncRNAs noise-induced hearing loss phenotypic variation repair of hair cell

Extraction and analysis of tree canopy height information in high-voltage transmission-line corridors by using integrated optical remote sensing and liDAR

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Geodesy and Geodynamics 2023年第3期14卷 292-303页

作者： Jinpeng Hao xiuguang li Hong Wu Kai yang Yumeng Zeng Yu Wang Yuanjin Pan State Grid Ningxia Electric Power Research Institute Yinchuan 750011China School of Electrical Engineering and Automation Wuhan UniversityWuhan 430061China School of Geodesy and Geomatics Wuhan UniversityWuhan 430079China Hubei LuoJia Laboratory Wuhan UniversityWuhan 430079China

Traditional inspection methods cannot quickly and accurately monitor tree barriers and safeguard the transmission *** solve these problems,in this study,we proposed a rapid canopy height information extraction method using optical remote sensing and liDAR,and used UAV optical imagery with liDAR to monitor the height of trees in a university and a high-voltage transmission line corridor in the Ningxia *** results showed that the relative error of tree height extraction using UAV optical images was less than 5%,and the lowest relative error was 0.11%.The determination coefficient R^(2) between the optical image tree height extraction results and the measured tree height was 0.97,thus indicating a high correlation for *** the field of tree barrier monitoring,the determination coefficient R^(2) of tree height extracted using airborne liDAR point cloud,and canopy height model(CHM)and of the measured tree height were 0.947 and 0.931,*** maximum and minimum relative error in tree height extraction performed using point cloud was 2.91%and 0.2%,respectively,with an extraction accuracy of over 95%.The experimental results demonstrated that it is feasible to use UAV optical remote sensing and liDAR in monitoring tree barriers and tree height information extraction quickly and accurately,which is of great significance for the risk assessment and early warning of tree barriers in transmission-line corridors.

关键词： UAV liDAR Power line Tree height

Secure Scheme for Locating Disease-Causing Genes Based on Multi-Key Homomorphic Encryption

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Tsinghua Science and Technology 2022年第2期27卷 333-343页

作者： Tanping Zhou Wenchao liu Ningbo li xiaoyuan yang Yiliang Han Shangwen Zheng Tanping Zhou is with the College of Cryptography Engineering Engineering University of People’s Armed PoliceXi’an 710086China TCA Laboratory State Key Laboratory of Computer ScienceInstitute of SoftwareChinese Academy of SciencesBeijing 100080China the College of Cryptography Engineering Engineering University of People’s Armed PoliceXi’an 710086China the People’s Armed Police Command College China Tianjin 300100China

Genes have great significance for the prevention and treatment of some diseases.A vital consideration is the need to find a way to locate pathogenic genes by analyzing the genetic data obtained from different medical institutions while protecting the privacy of patients’genetic *** this paper,we present a secure scheme for locating disease-causing genes based on Multi-Key Homomorphic Encryption(MKHE),which reduces the risk of leaking genetic ***,we combine MKHE with a frequency-based pathogenic gene location *** medical institutions use MKHE to encrypt their genetic *** cloud then homomorphically evaluates specific gene-locating circuits on the encrypted genetic ***,whereas most location circuits are designed only for locating monogenic diseases,we propose two location circuits(TH-intersection and Top-q)that can locate the disease-causing genes of polygenic ***,we construct a directed decryption protocol in which the users involved in the homomorphic evaluation can appoint a target user who can obtain the final decryption *** experimental results show that compared to the JWB+17 scheme published in the journal Science,our scheme can be used to diagnose polygenic diseases,and the participants only need to upload their encrypted genetic data once,which reduces the communication traffic by a few hundred-fold.

关键词： public key encryption Multi-Key Homomorphic Encryption(MKHE) fully homomorphic encryption disease-causing genes secure location of disease-causing genes

Modified Multi-Key Fully Homomorphic Encryption Based on NTRU Cryptosystem without Key-Switching

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Tsinghua Science and Technology 2020年第5期25卷 564-578页

作者： Xiaoliang Che Tanping Zhou Ningbo li Haonan Zhou Zhenhua Chen xiaoyuan yang the Engineering University of People's Armed Police Xi’an 710086China Xi’an University of Science and Technology Xi'an 710054China

The Multi-Key Fully Homomorphic Encryption (MKFHE) based on the NTRU cryptosystem is an important alternative to the post-quantum cryptography due to its simple scheme form,high efficiency,and fewer ciphertexts and *** 2012,Lopez-Alt et *** the first NTRU-type MKFHE scheme,the LTV12 scheme,using the key-switching and modulus-reduction techniques,whose security relies on two assumptions:the Ring Learning With Error (RLWE) assumption and the Decisional Small Polynomial Ratio (DSPR) ***,the LTV12and subsequent NTRU-type schemes are restricted to the family of power-of-2 cyclotomic rings,which may affect the security in the case of subfield ***,the key-switching technique of the LTV12 scheme requires a circular application of evaluation keys,which causes rapid growth of the error and thus affects the circuit *** this paper,an NTRU-type MKFHE scheme over prime cyclotomic rings without key-switching is proposed,which has the potential to resist the subfield attack and decrease the error exponentially during the homomorphic evaluating ***,based on the RLWE and DSPR assumptions over the prime cyclotomic rings,a detailed analysis of the factors affecting the error during the homomorphic evaluations in the LTV12 scheme is ***,a Low Bit Discarded&Dimension Expansion of Ciphertexts (LBD&DEC) technique is proposed,and the inherent homomorphic multiplication decryption structure of the NTRU is proposed,which can eliminate the key-switching operation in the LTV12 ***,a leveled NTRU-type MKFHE scheme is developed using the LBD&DEC and modulus-reduction *** analysis shows that the proposed scheme compared to the LTV12 scheme can decrease the magnitude of the error exponentially and minimize the dimension of ciphertexts.

关键词： NTRU-type Multi-Key Fully Homomorphic Encryption(MKFHE) prime cyclotomic rings Low Bit Discarded(LBD) homomorphic multiplication decryption structure

Optimization of TC11 alloy forging parameters using processing maps

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Rare Metals 2011年第3期30卷 222-226页

作者： li Miaoquan ZHANG xiaoyuan School of Materials Science and Engineering Northwestern Polytechnical University Xi＇an 710072 China

Isothermal compression of TC11 alloy at the deformation temperatures ranging from 1023 to 1323 K with an interval of 20 K, the strain rates of 0.001, 0.1, 1.0, and 10.0 s-1, and the height reductions of 50% and 70% was conducted on a Gleeble-1500D thermomechanical simulator. According to the experimental results, the isothermal compression and the processing maps of TC11 alloy at different strains were drawn by using the dynamic material model （DMM）. Based on the processing maps, the proper forging parameters, including a combination of defor-mation temperature and strain rate, vary with the strain in different phases of TC11 alloy.

关键词： forging isothermal compression optimization titanium alloys processing maps

A HEVC Video Steganalysis Method Using the Optimality of Motion Vector Prediction

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Computers, Materials & Continua 2024年第5期79卷 2085-2103页

作者： Jun li Minqing Zhang Ke Niu Yingnan Zhang xiaoyuan yang College of Cryptography Engineering Engineering University of the Chinese People’s Armed Police ForceXi’an710086China Key Laboratory of Network and Information Security of the Chinese People’s Armed Police Force Xi’an710086China

Among steganalysis techniques,detection against MV(motion vector)domain-based video steganography in the HEVC(High Efficiency Video Coding)standard remains a challenging *** the purpose of improving the detection performance,this paper proposes a steganalysis method that can perfectly detectMV-based steganography in ***,we define the local optimality of MVP(Motion Vector Prediction)based on the technology of AMVP(Advanced Motion Vector Prediction).Secondly,we analyze that in HEVC video,message embedding either usingMVP index orMVD(Motion Vector Difference)may destroy the above optimality of *** then,we define the optimal rate of MVP as a steganalysis ***,we conduct steganalysis detection experiments on two general datasets for three popular steganographymethods and compare the performance with four state-ofthe-art steganalysis *** experimental results demonstrate the effectiveness of the proposed feature ***,our method stands out for its practical applicability,requiring no model training and exhibiting low computational complexity,making it a viable solution for real-world scenarios.

关键词： Video steganography video steganalysis motion vector prediction motion vector difference advanced motion vector prediction local optimality