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Design of high-performance energy integrator detector for wideband radar

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Journal of Systems Engineering and Electronics 2019年第6期30卷 1110-1118页

作者： CHANG Jiayun fu Xiongjun JIANG wen XIE Min School of Information and Electronics Beijing Institute of Technology

Target detection for wideband radar has recently received extensive attention. The classical energy integrating(EI)detector will always accumulate excess clutter or noise energy,which leads to unacceptable performance deterioration if the detection window is not selected properly. In this paper, an EI detector for the distributed targets in the Gaussian environment is ***, at the stage of preparatory work, the target models are proposed, then, the problem formulation is introduced. Subsequently,in the aspect of optimizing the method of detection window search and the method of threshold setting, the detailed design stages of the proposed detector are provided. furthermore, theoretical analyses show that the proposed detector is easy to hardware implementation, and it does not need the prior knowledge about the spatial distribution of the target scattering centers in practical radar detection application. Finally, the performance assessment conducted by Monte Carlo simulations verifies that the proposed detector outperforms the conventional detectors.

关键词： radar detection distributed target integration detec tor.

Wideband radar detector based on characteristic parameters of echoes

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Journal of Systems Engineering and Electronics 2019年第5期30卷 897-904页

作者： CHANG Jiayun fu Xiongjun JIANG wen XIE Min School of Information and Electronics Beijing Institute of Technology

The statistical characterization of radar range cells with the target signals is much more distinct than that of the range cells with noise-only ***,the quasi-optimal detection principle based on the characteristic parameters of echo signals is adopted to develop a detector of range-spread targets in Gaussian ***,the characteristic parameters of the return signals in the entire range profiles of radar are ***,the clustering analysis of the characteristic parameter matrix is discussed to extract the test statistic of ***,the probabilities of detection and false alarm of the proposed detector are *** analysis shows that the proposed detector does not need the prior knowledge about the spatial distribution of the target scattering centers in practical scenarios,and it is simple and robust even in low signal-to-noise ratio(low-SNR)*** Carlo(MC)simulations reveal that the detection performance of the proposed detector outperforms the conventional detectors.

关键词： wideband radar mathematical statistics characteristic parameter clustering analysis

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区域资源条件评价指标体系建立的研究

山东科技大学学报（自然科学版） 2001年第3期20卷 91-94页

作者：袁清和付文福孙会君山东科技大学资源与环境工程学院泰安271019 北方交通大学北京100044

从探讨建立区域资源条件评价指标体系的原则入手 ,对区域内各类资源的概念、特性及其构成进行了系统分析 ,进而建立了较为完善的区域资源条件评价指标体系。

关键词：区域资源条件评价指标体系可持续发展资源评价人力资源自然资源市场资源

Latitudinal migration of sunspots based on the ESAI database

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Research in Astronomy and Astrophysics 2018年第1期18卷 83-94页

作者： Juan Zhang fu-Yu Li wen Feng Yunnan Observatories Chinese Academy of Sciences Kunming 650011 China Research Center of Analysis and Measurement Kunming University of Science and Technology Kunming 650093 China University of Chinese Academy of Sciences Beijing 100049 China Key Laboratory of Solar Activity National Astronomical Observatories Chinese Academy of Sciences Beijing 100012 China State Key Laboratory of Space Weather Chinese Academy of Sciences Beijing 100190 China

The latitudinal migration of sunspots toward the equator,which implies there is propagation of the toroidal magnetic flux wave at the base of the solar convection zone,is one of the crucial observational bases for the solar dynamo to generate a magnetic field by shearing of the pre-existing poloidal magnetic field through differential *** Extended time series of Solar Activity Indices（ESAI）elongated the Greenwich observation record of sunspots by several decades in the *** this study,ESAI＇s yearly mean latitude of sunspots in the northern and southern hemispheres during the years 1854 to 1985 is utilized to statistically test whether hemispherical latitudinal migration of sunspots in a solar cycle is linear or *** is found that a quadratic function is statistically significantly better at describing hemispherical latitudinal migration of sunspots in a solar cycle than a linear *** addition,the latitude migration velocity of sunspots in a solar cycle decreases as the cycle progresses,providing a particular constraint for solar dynamo ***,the butterfly wing pattern with a faster latitudinal migration rate should present stronger solar activity with a shorter cycle period,and it is located at higher latitudinal position,giving evidence to support the Babcock-Leighton dynamo mechanism.

关键词： Sun:activity Sun:general Sun:sunspots methods:data analysis

Effective Elastic Properties of 3-Phase Particle Reinforced Composites with Randomly Dispersed Elastic Spherical Particles of Different Sizes Dedicated to Professor Karl Stark Pister for his 95th birthday

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Computer Modeling in Engineering & Sciences 2021年第12期129卷 1305-1328页

作者： Yu-fu Ko Jiann-wen Woody Ju Civil Engineering and Construction Engineering Management California State UniversityLong BeachCA 90840-5101USA Civil and Environmental Engineering University of CaliforniaLos AngelesCA 90095-1593USA

Higher-order multiscale structures are proposed to predict the effective elastic properties of 3-phase particle reinforced composites by considering the probabilistic spherical particles spatial distribution,the particle interactions,and utilizing homogenization with ensemble volume average *** matrix material,spherical particles with radius a1,and spherical particles with radius a2,are denoted as the 0th phase,the 1st phase,and the 2nd phase,***,the two inhomogeneity phases are different particle sizes and the same elastic material *** higher-order(in ratio of spherical particle sizes to the distance between the centers of spherical particles)bounds on effective elastic properties of 3-phase particle reinforced proposed Formulation II and Formulation I derive *** a special case,i.e.,particle size of the 1st phase is the same as that of the 2nd phase,the proposed formulations reduce to 2-phase *** theoretical predictions demonstrate excellent agreement with selected experimental *** addition,several numerical examples are presented to demonstrate the competence of the proposed frameworks.

关键词： Particle reinforced composites micromechanics spherical particle interactions ensemble volume average homogenization probabilistic spatial distribution higher-order bounds multiscale

Correlations of conserved charges and QCD phase structure

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Chinese Physics C 2021年第4期45卷 380-393页

作者： Rui wen Wei-jie fu School of Physics Dalian University of TechnologyDalian 116024China

Correlations of conserved charges,i.e.,the baryon number,electric charge,and strangeness,are calculated at finite temperature and chemical potentials up to the fourth *** calculations are done ina 2+1 flavor low energy effective theory,in which the quantum and thermal fluctuations are encoded through the evolution of flow equations within the functional renormalization group *** neutrality and a fixed ratio of the electric charge to the baryon number density are implemented throughout the *** find that higher-order correlations incorporate more sensitive critical dynamics than the quadratic *** addition,a non-monotonic dependence of the fourth-order correlations between the baryon number and strangeness,i.e.,-χ_(31)^(BS)/χ_(2)^(S)and χ_(22)^(BS)/χ_(2)^(S),on the collision energy is also observed.

关键词： QCD phase transition functional renormalization group chiral phase transition

The dual antimicrobial and immunomodulatory roles of host defense peptides and their applications in animal production

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Journal of Animal Science and Biotechnology 2023年第2期14卷 501-514页

作者： Di Wu Linglong fu Weizhang wen Na Dong State Key Laboratory of Animal Nutrition College of Animal Science and TechnologyChina Agricultural UniversityBeijing 100193China

Host defense peptides(HDPs)are small molecules with broad-spectrum antimicrobial activities against infectious bacteria,viruses,and *** evidence suggests that HDPs can also indirectly protect hosts by modulating their immune *** to these dual roles,HDPs have been considered one of the most promising antibiotic substitutes to improve growth performance,intestinal health,and immunity in farm *** review describes the antimicrobial and immunomodulatory roles of host defense peptides and their recent applications in animal production.

关键词： Antimicrobials Host defense peptides Immunomodulation Poultry Ruminants Swine

Quantization of black hole entropy from unstable circular null geodesics

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Science China(Physics,Mechanics & Astronomy) 2016年第4期59卷 29-36页

作者： Shao-wen Wei Yu-Xiao Liu Chun-E fu Institute of Theoretical Physics Lanzhou University School of Science Xi'an Jiaotong University

The quasinormal mode frequencies can be understood from the massless particles trapped at the unstable circular null geodesics and slowly leaking out to infinity. Based on this viewpoint, in this paper, we semiclassically construct the entropy spectrum of the static and stationary black holes from the null geodesics. The result shows that the spacing of the entropy spectrum only depends on the property of the black hole in the eikonal limit. Moreover, for a black hole far from the extremal case, the spacing is found to be smaller than 2π for any dimension, which is very different from the result of the previous work by using the usual quasinormal mode frequencies.

关键词： black hole entropy spectrum null geodesics quantization

A novel structure of quasi-monolayered NiCo-bimetal-phosphide for superior electrochemical performance

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Journal of Energy Chemistry 2022年第11期31卷 203-211,I0007页

作者： Long Zhao Ming wen Yakun Tian Qingsheng Wu Yongqing fu School of Chemical Science and Engineering Shanghai Key Laboratory of Chemical Assessment and SustainabilityState Key Laboratory of Pollution Control and Resource ReuseTongji UniversityShanghai 200092China Faculty of Engineering and Environment Northumbria UniversityNewcastle upon TyneNE18STUnited Kingdom

Bimetallic transition metal phosphides(TMPs)as potential candidates for superior electrochemical performance are still facing great challenges in the controllable preparation of two-dimensional(2 D)structures with high aspect ***,a novel structure of quasi-monolayered NiCo-bimetal-phosphide(NiCoP)has been designed and successfully synthesized by the newly developed process combined with ultrasonic-cavitation and *** is the first time to break through the controllable preparation of 2 D bimetal-phosphides with a thickness of 0.98 nm in *** on the advantages of 2 D quasi-monolayer structure with dense crystalline-amorphous interface and the reconfigured electronic structure between Ni^(δ+)/Co^(δ+)and P^(δ-),the optimized Ni_(5%)CoP exhibits an outstanding bifunctional performance for electrocatalyzing both hydrogen evolution reaction and oxygen evolution reaction in an alkaline ***_(5%)CoP presents lower overpotentials and voltage of 84 mV&259 mV and1.48 V at the current density of 10 mA cm^(-2)for HER&DER and overall water splitting,respectively,which are superior to most other reported 2 D *** work provides a new strategy to optimize the performance of electrolytic water for bimetal-phosphates and it may be of significant value in extending the design of other ultrathin 2 D structured catalysts.

关键词： 2D quasi-monolayer Hydrogen evolution reaction Bimetal phosphide Oxygen evolution reaction Ultrasonic-cavitation