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基于正交投影的子带信息几何雷达弱小目标检测方法

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雷达学报（中英文） 2023年第4期12卷 776-792页

作者：杨政程永强吴昊黎湘王宏强国防科技大学电子科学学院长沙410073

基于信息几何理论的雷达目标检测是一种新兴的技术,它将目标检测问题转化为流形上目标与杂波的区分问题,在低信杂比检测中具有优势。对于复杂背景下的弱小目标检测,目标与杂波难以区分,限制着检测性能。因此,该文基于矩阵信息几何检测器... 详细信息

基于信息几何理论的雷达目标检测是一种新兴的技术,它将目标检测问题转化为流形上目标与杂波的区分问题,在低信杂比检测中具有优势。对于复杂背景下的弱小目标检测,目标与杂波难以区分,限制着检测性能。因此,该文基于矩阵信息几何检测器,提出一种基于正交投影的子带信息几何目标检测方法。该文利用滤波器组对雷达回波信号进行子带分解,并在矩阵流形上稳健估计子带内强杂波信号子空间,提出基于流形的正交投影方法以抑制强杂波,增强目标与杂波的区分性。最后,采用仿真数据和实测海杂波数据验证所提方法的有效性。结果表明,所提方法能够有效抑制强杂波,具有较好的检测性能。

关键词：雷达弱小目标检测信息几何矩阵流形子带分解正交投影杂波抑制

Statistical properties of ideal photons in a two-dimensional dye-filled spherical cap cavity

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Chinese Physics B 2024年第10期33卷 258-268页

作者： Ze cheng School of Physics Huazhong University of Science and TechnologyWuhan 430074China

Within the framework of quantum statistical mechanics,we have proposed an exact analytical solution to the problemof Bose-Einstein condensation(BEC)of harmonically trapped two-dimensional(2D)ideal *** utilize this analyticalsolution to investigate the statistical properties of ideal photons in a 2D dye-filled spherical cap *** resultsof numerical calculation of the analytical solution agree completely with the foregoing experimental results in the BEC ofharmonically trapped 2D ideal *** analytical expressions of the critical temperature and the condensate fractionare derived in the thermodynamic *** is found that the 2D critical photon number is larger than the one-dimensional(1D)critical photon number by two orders of *** spectral radiance of a 2D spherical cap cavity has a sharppeak at the frequency of the cavity cutoff when the photon number exceeds the critical value determined by a temperature.

关键词： rigorous results in statistical mechanics Bose-Einstein condensation 2D photons

Ternary layered boride MoAlB:A novel thermo-regulation microwave absorbing ceramic material

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Journal of Advanced Ceramics 2024年第5期13卷 699-710页

作者： Zhangjue Wang Fan Zhang Nannan Wang Wei Li yongqiang Chen Hailong Wang Rui Zhang Yanqiu Zhu Bingbing Fan School of Material Science and Engineering Zhengzhou UniversityZhengzhou 450001China Henan Academy of Sciences Zhengzhou 450046China State Key Laboratory of Featured Metal Materials and Life Cycle Safety for Composite Structures MOE Key Laboratory of New Processing Technology for Nonferrous Metals MaterialsSchool of ResourcesEnvironment and MaterialsGuangxi UniversityNanning 530004China Department of Materials and Earth Sciences Technical University of DarmstadtDarmstadt 64287Germany School of Material Science and Engineering Luoyang Institute of Science and TechnologyLuoyang 471023China Department of Engineering Faculty of EnvironmentScience and EconomyUniversity of ExeterExeter EX44QFUK

In the context of the fifth-generation(5G)smart era,the demand for electromagnetic wave(EMW)-absorbing materials has become increasingly prominent,so it is necessary to explore promising candidate *** work focuses on the exploration of the material absorbing properties of a MoAlB MAB(MAB represents a promising group of alternatives,where M stands for a transition metal,A typically denotes Al,and B is boron)phase ***,the first-principles calculations were performed to reveal the unique crystal and layered structure of the MoAlB ceramics and to predict their potential for use as an EMW absorption ***,a series of MoAlB ceramics were synthesized at temperatures ranging from 800 to 1300℃,and the influence of temperature on the phase compositions and microstructures of the obtained MoAlB ceramics was characterized and ***,the practical EMW absorption performance of the prepared MoAlB ceramics was evaluated via a combination of experiments and radar cross-sectional *** MoAlB sample synthesized at 900℃ exhibits superior EMW absorption performance,achieving an impressive minimum reflection loss(RL)of−50.33 *** unique layered structure and good electrical conductivity of the MoAlB samples are the main reasons for their enhanced wave absorption performance,which provides interfacial polarization and multiple dielectric loss ***,this study not only contributes to the understanding of the preparation of MoAlB materials but also provides potential guidance for their utilization in the realm of electromagnetic wave absorption.

关键词： MoAlB electronic band structure electromagnetic wave(EMW)absorption layered ternary boride density of states

Simple chemical synthesis and isotropic negative thermal expansion in MHfF_(6)(M=Ca,Mn,Fe,and Co)

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Nano Research 2024年第3期17卷 2195-2203页

作者： yongqiang Qiao Sen Zhang Peixian Zhang Juan Guo Andrea Sanson Xi Zhen Kaiyue Zhao Qilong Gao Jun Chen Key Laboratory of Materials Physics of Ministry of Education and School of Physics and MicroelectronicsZhengzhou UniversityZhengzhou 450052China Department of Physics and Astronomy University of PadovaPadova I-35131Italy Beijing Advanced Innovation Center for Materials Genome Engineering Department of Physical ChemistryUniversity of Science and Technology BeijingBeijing 100083China

The rapid progress of modern technologies has accelerated the prominence of thermal expansion mismatch between materials,and tunable thermal expansion materials will be a powerful safeguard against this ***,isotropic MHfF_(6)(M=Ca,Mn,Fe,and Co)compounds with tunable thermal expansion have been produced via a low-cost synthetic method and *** utilizing temperature dependent X-ray diffraction(XRD)and Raman spectroscopy,combined with first principles calculations,it was revealed that the transverse thermal vibrations of the F atoms are dominated by low-frequency phonons with negative Grüneisen parameters and are therefore the origin of the negative thermal expansion(NTE).Very interestingly,with the increase of the M atomic number,the metal…F atomic linkages become stiffer,reducing the number of vibrational modes with negative Grüneisen parameters,so that the strong NTE can be gradually adjusted to moderate NTE and to near zero thermal *** present study achieves the tunable thermal expansion in a new compound family and shed light on the internal mechanism from the perspective of lattice vibrational dynamics.

关键词： negative thermal expansion fluorides chemical synthesis nanosheet structure first principles calculations

Insights into microbiota community dynamics and flavor development mechanism during golden pomfret(Trachinotus ovatus)fermentation based on single-molecule real-time sequencing and molecular networking analysis

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Food Science and Human Wellness 2024年第1期13卷 101-114页

作者： Yueqi Wang Qian Chen Huan Xiang Dongxiao Sun-Waterhouse Shengjun Chen yongqiang Zhao Laihao Li Yanyan Wu Key Laboratory of Aquatic Product Processing Ministry of Agriculture and Rural Affairs of The People’s Republic of ChinaNational R&D Center for Aquatic Product ProcessingSouth China Fisheries Research InstituteChinese Academy of Fishery SciencesGuangzhou 510300China Co-Innovation Center of Jiangsu Marine Bio-industry Technology Jiangsu Ocean UniversityLianyungang 222005China School of Chemical Sciences The University of AucklandAuckland 92019New Zealand Collaborative Innovation Center of Seafood Deep Processing Dalian Polytechnic UniversityDalian 116034China

Popular fermented golden pomfret(Trachinotus ovatus)is prepared via spontaneous fermentation;however,the mechanisms underlying the regulation of its flavor development remain *** study shows the roles of the complex microbiota and the dynamic changes in microbial community and flavor compounds during fish ***-molecule real-time sequencing and molecular networking analysis revealed the correlations among different microbial genera and the relationships between microbial taxa and volatile *** underlying flavor development were also elucidated via KEGG based functional ***,Shewanella,and Staphylococcus were the dominant microbial ***-nine volatile compounds were detected in the fermented fish samples,with thirteen identified as characteristic volatile compounds(ROAV>1).Volatile profiles resulted from the interactions among the microorganisms and derived enzymes,with the main metabolic pathways being amino acid biosynthesis/metabolism,carbon metabolism,and glycolysis/*** study demonstrated the approaches for distinguishing key microbiota associated with volatile compounds and monitoring the industrial production of high-quality fermented fish products.

关键词： Fermented golden pomfret Microbiota community Volatile compound Co-occurrence network Metabolic pathway

Identification and fine mapping of qSW2 for leaf slow wilting in soybean

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The Crop Journal 2024年第1期12卷 244-251页

作者： Shengyou Li Changling Wang Chunjuan Yan Xugang Sun Lijun Zhang yongqiang Cao Wenbin Wang Shuhong Song Institute of Crop Research Liaoning Academy of Agricultural SciencesShenyang 110161LiaoningChina

Drought is one of the abiotic stresses limiting the production of soybean(Glycine max).Elucidation of the genetic and molecular basis of the slow-wilting(SW)trait of this crop offers the prospect of its genetic improvement.A panel of 188 accessions and a set of recombinant inbred lines produced from a cross between cultivars Liaodou 14 and Liaodou 21 were used to identify quantitative-trait loci(QTL)associated with *** were genotyped by Specific-locus amplified fragment sequencing and seedling leaf wilting was assessed under three water-stress treatments.A genome-wide association study identified 26 SW-associated single-nucleotide polymorphisms(SNPs),including three located in a 248-kb linkage-disequilibrium(LD)block on chromosome *** mapping revealed a major-effect QTL,qSW2,associated with all three treatments and adjacent to the LD *** mapping in a BC_(2)F_(3) population derived from a backcross between Liaodou 21 and R26 confined qSW2 to a 60-kb *** expression and sequence variation analysis identified the gene Glyma.02 g218100,encoding an auxin transcription factor,as a candidate gene for *** results will contribute significantly to improving drought-resistant soybean cultivars by providing genetic information and resources.

关键词： Drought GWAS Linkage mapping Slow wilting Soybean(Glycine max)

Weighted sum power maximization for STAR-RIS-aided SWIPT systems with nonlinear energy harvesting

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Science China(Information Sciences) 2024年第10期67卷 343-358页

作者： Weiping SHI Cunhua PAN Feng SHU Yongpeng WU Jiangzhou WANG yongqiang BAO Jin TIAN School of Network and Communication Nanjing Vocational College of Information Technology National Mobile Communications Research Laboratory Southeast University School of Information and Communication Engineering Hainan University School of Electronic and Optical Engineering Nanjing University of Science and Technology Shanghai Key Laboratory of Navigation and Location Based Services Shanghai Jiao Tong University School of Engineering University of Kent School of Information and Communication Engineering Nanjing Institute of Technology Engineering School of Networks and Telecommunications Jinling Institute of Technology

The conventional reconfigurable intelligent surface(RIS) is limited to reflecting incident signals,thereby imposing constraints on the placement of the transmitter and receiver, which hinders achieving comprehensive signal coverage across an entire area. This paper investigates a simultaneously transmitting and reflecting(STAR)-RIS-aided simultaneous wireless information and power transfer(SWIPT) system with a nonlinear energy harvesting model under three different RIS transmission protocols: energy splitting(ES),time switching(TS), and mode switching(MS). The objective of this paper is to maximize the weighted sum power(WSP) of all energy harvesting receivers(EHRs) while ensuring fairness in the collected power among them. This is achieved by jointly optimizing the transmit beamforming at the base station(BS)and the transmission and reflection coefficients at the STAR-RIS, subject to rate constraints for information decoding receivers(IDRs), transmit power constraint at the BS, and coefficient constraints of each element at the STAR-RIS corresponding to the three protocols. Solving this optimization problem poses challenges because of the complicated objective function and numerous coupled optimization variables of the ES STAR-RIS. To address this complexity, an efficient alternating optimization(AO) approach is proposed as an iterative solution method that achieves suboptimal results. The AO algorithm is then extended to MS STAR-RIS and TS STAR-RIS. Specifically, for MS STRA-RIS, binary constraints in the STAR-RIS coefficient optimization subproblem are handled using the first-order approximation technique along with the penalty function method. For TS STAR-RIS, apart from optimizing BS transmit beamforming and STAR-RIS coefficients subproblems, the transmission and reflection time allocation of STAR-RIS also needs *** findings demonstrate that compared to conventional RIS-aided systems, utilizing three different protocols in a STAR-RIS-aided sy

关键词： STAR-RIS beamforming SWIPT alternating optimization nonlinear energy harvesting

Analysis of multi-objective optimisation method for main insulation structure configuration scheme of valve-side winding of ultra-high voltage converter transformer considering multi-field coupling

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High Voltage 2024年第2期9卷 296-308页

作者： Lijun Yang Zhidong cheng Li cheng Ruijin Liao State Key Laboratory of Power Transmission Equipment Technology School of Electrical EngineeringChongqing UniversityChongqingChina

Because DC conductivities of oil-paper materials can be easily affected by electric field and temperature,the electrical properties under electro-thermal coupling of oil-paper materials should be considered when optimising the insulation structure of valve-side winding of the converter *** on the finite element multi-physical field coupling simulation,the multi-objective optimisation of main insulation structure of valve-side winding is carried *** view of the high time consuming of multi-physical field calculation and the actual needs of an insulation structure optimisation,the Kriging method and technique for order preference by similarity to the ideal solution(TOPSIS)method are introduced,and combines them with NSGA-II to obtain a joint algorithm that can be used for the optimisation of insulation structure of the converter *** using the joint algorithm of multi-objective optimisation,the insulation structure configuration scheme of valve-side winding is *** can be seen from the experiment result that,on the one hand,the joint algorithm adopted can obtain the insulation structure configuration scheme that meets the design *** the other hand,when facing the configuration scheme optimisation under multi-field coupling,the computational time required by this method is only 0.15%of that required by original genetic algorithm.

关键词： converter insulation coupling

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一种分布式信源编码中最优量化器的设计

电视技术 2013年第7期37卷 129-131页

作者：郑婷一程永强太原理工大学通信技术研究室山西太原030024

针对传统的向量量化压缩的不足性,提高量化效果的方法主要是增加向量的维数,但同时增加了计算的复杂性。为了解决分布式编码中量化器的设计问题,在联合条件熵约束的条件下,着重从WZ量化器的最优条件分析,提出了一种Lloyd迭代算法,通过... 详细信息

针对传统的向量量化压缩的不足性,提高量化效果的方法主要是增加向量的维数,但同时增加了计算的复杂性。为了解决分布式编码中量化器的设计问题,在联合条件熵约束的条件下,着重从WZ量化器的最优条件分析,提出了一种Lloyd迭代算法,通过实验证明,该算法比传统的算法更可以保证量化器的局部最优性。

关键词：分布式编码 WZ量化器 Lloyd算法局部最优