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Automatic modulation recognition of radio fuzes using a DR2.-based adaptive denoising method and textural feature extraction

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Defence Technology（防务技术） 2024年第4期34卷 328-338页

作者： Yangtian Liu Xiaopeng Yan Qiang Liu Tai An Jian dai Science and Technology on Electromechanical Dynamic Control Laboratory School of Mechatronical EngineeringBeijing Institute of TechnologyBeijing 100081China China Research and Development Academy of Machinery Equipment Beijing 100089China

The identification of intercepted radio fuze modulation types is a prerequisite for decision-making in interference ***,the electromagnetic environment of modern battlefields is complex,and the signal-to-noise ratio(SNR)of such environments is usually low,which makes it difficult to implement accurate recognition of radio *** solve the above problem,a radio fuze automatic modulation recognition(AMR)method for low-SNR environments is ***,an adaptive denoising algorithm based on data rearrangement and the two-dimensional(2.)fast Fourier transform(FFT)(DR2.)is used to reduce the noise of the intercepted radio fuze intermediate frequency(IF)***,the textural features of the denoised IF signal rearranged data matrix are extracted from the statistical indicator vectors of gray-level cooccurrence matrices(GLCMs),and support vector machines(SVMs)are used for *** DR2.-based adaptive denoising algorithm achieves an average correlation coefficient of more than 0.76 for ten fuze types under SNRs of-10 d B and above,which is higher than that of other typical *** trained SVM classification model achieves an average recognition accuracy of more than 96%on seven modulation types and recognition accuracies of more than 94%on each modulation type under SNRs of-12.d B and above,which represents a good AMR performance of radio fuzes under low SNRs.

关键词： Automatic modulation recognition Adaptive denoising Data rearrangement and the 2. FFT(DR2.) Radio fuze

R-matrix for the 8-Dimensional Spin Representation of Uq(so7)

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Acta Mathematica Sinica,English Series 2024年第2期40卷 485-497页

作者： hong Mei HU Nai hong HU School of Mathematical Sciences Suzhou University of Science and TechnologySuzhou 215009P.R.China School of Mathematical Sciences MOE Key Laboratory of Mathematics and Engineering Applications&Shanghai Key Laboratory of PMMPEast China Normal UniversityShanghai 200241P.R.China

The purpose of the paper is to describe the solution to the quantum Yang-Baxter equation associated with the 8-dimensional spin representation Tsp of Uq(so7).The self-duality of Tsp and the symmetry of the corresponding braiding matrix are ***,the minimal polynomial of the braiding R-matrix of Tsp is presented explicitly in an ingenious method by taking advantage of nice features of the spin representation Tsp.

关键词： Braiding R-matrix spin module minimal polynomial

Influence of Current Density on the Photocatalytic Activity of Nd:TiO_(2. Coatings

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Journal of Wuhan University of Technology(Materials Science) 2024年第1期39卷 32-38页

作者：施渊吉 ZHANG Zhen dai Yunzhong LI Jingxiao CHEN Zeyu School of Mechanical Engineering Nanjing Vocational University of Industry TechnologyNanjing 210046China College of Material Science and Technology Nanjing University of Aeronautics and AstronauticsNanjing 210016China School of Materials Science and Engineering Nanjing Institute of TechnologyNanjing 211167China Key Laboratory of Modern Agricultural Equipment and Technology Jiangsu UniversityZhenjiang 212013China

The Nd:TiO_(2.)PEO coatings were formed in a phosphate-based electrolyte with the addition of Nd_(2.O_(3 )under the current density of 150,2.0,2.0 and 300 m A/cm^(2..SEM results showed that the micropores decreased on quantity and increased on scale with the increasing current *** results revealed that the roughness of the coatings increased with the increasing current *** and composition analysis showed that the Nd:TiO_(2. coatings were mainly composed of anatase and rutile *** the anatase phase content has reached the maximum value at the current density of 2.0 m A/cm^(2..XPS results indicated that Ti2. spin-orbit components of the Nd:TiO_(2. coatings are shifted towards higher binding energy,compared with the pure TiO_(2. coating,suggesting that some of the Nd^(3+)ions are combined with TiO_(2. lattice and led to *** test showed that the photocatalytic activity of Nd:TiO_(2. coatings varied in the same pattern with the anatase content variation in Nd:TiO_(2. *** photocatalytic experiment results show that the photocatalytic activity of Nd:TiO_(2. coatings can be greatly enhanced with moderate amount of Nd^(3+).However,excessive amount of Nd^(3+)does not have an effective impact on the photoctalytic activity improvement.

关键词： PEO current density AFM XPS Nd:TiO_(2. photocatalytic

The Influence of Different Solar System Planetary Ephemerides on Pulsar Timing

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Research in Astronomy and Astrophysics 2024年第8期24卷 85-99页

作者： Jian-Peng dai Wei Han Na Wang School of Physical Science and Technology Xinjiang UniversityUrumqi 830046China Xinjiang Astronomical Observatory Chinese Academy of SciencesUrumqi 830011China University of Chinese Academy of Sciences Beijing 100049China Xinjiang Key Laboratory of Radio Astrophysics Urumqi 830011China

Pulsar timing offers a comprehensive avenue for exploring diverse topics in physics and *** solar system planetary ephemeris is crucial for pulsar timing as it provides the positions and velocities of solar system planets including the ***,it is inevitable that inherent inconsistencies exist in these *** between various ephemerides can significantly impact pulsar timing and parameter ***,pulsar timing highly depends on the JPL DE ephemeris,for instance,the Pulsar Timing Array data analysis predominantly utilizes *** this study,we examine inconsistencies across various ephemeris series,including JPL DE,EPM,and ***,discrepancies emerge particularly between the current ephemeris DE436 and the earliest released ephemeris DE2.0,as well as the most recent ephemerides,e.g.,DE440,INPOP2.A,and *** detailed analysis of the effects of ephemeris on geometric correction procedures for the conversion of measured topocentric times of arrival is presented in this *** researches reveal that variations in the Roemer delays across different ephemerides lead to distinct *** timing residuals and the fact that these discrepancies can be readily incorporated into the subsequent pulsar parameters,leading to inconsistent fitting estimates,suggest that the influence of errors in the ephemeris on the timing process might currently be underappreciated.

关键词： (stars)pulsars general-Planetary Systems-time-ephemerides

Spontaneous ignition of corrugated cardboard under dynamic high radiant flux

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Defence Technology（防务技术） 2024年第10期40卷 65-77页

作者： Liu Liu Yan Gu hong Yang Xing Wang Yang Zhou Xiaogan dai Yong Han Shanggang Wen Ming Li Congmei Lin Changgen Feng Fei Tang Yushi Wen Institute of Chemical Materials China Academy of Engineering PhysicsMianyang 621999China State Key Laboratory of Explosion Science and Technology Beijing Institute of TechnologyBeijing 100081China State Key Laboratory of Fire Science University of Science and Technology of ChinaHefei 230026China Institute of Applied Physics and Computational Mathematics China Academy of Engineering PhysicsBeijing 100088China

Understanding the response of solid combustibles under high radiant fluxes is critical in predicting the thermal damage from extreme *** the more moderate radiant fluxes in conventional hydrocarbon fires,extreme events such as strong explosion,concentrated sunlight and directed energy can generate dynamic radiant fluxes at the MW/m^(2. level,creating a unique threat to *** study investigates the pyrolysis and spontaneous ignition behaviors of corrugated cardboard by using both experimental and numerical methods,under 10-cm dynamic high radiant fluxes ranging from 0.2.to 1.2. MW/m^(2. for 10 *** spontaneous ignition process at dynamic high radiant fluxes was recorded and *** ignition modes were found at the critical radiant flux of 0.4 MW/m^(2.,namely hot-gas spontaneous ignition and hot-residue piloted *** latter is not the focus of this paper due to its extremely small probability of *** research reveals that the increase in flux intensity induces shorter delay times for both pyrolysis and ignition,lower ignition energy density,along with a corresponding rise in the critical mass flux and surface temperature at ignition *** simulation results are generally aligned with the experimental findings,despite some divergences may be attributed to model simplifications and parameter *** work contributes to a deeper insight into material behavior under extreme radiation,with valuable implications for fire safety and hazard assessment.

关键词： Extreme radiation Fire safety Corrugated cardboard Pyrolysis Ignition temperature

The tail risk safe haven property of China's energy futures against US market implied volatility

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Journal of Management Science and Engineering 2024年第2期9卷 271-291页

作者： Xingyu dai Peng-Fei dai Qunwei Wang Zhi-Yi Ouyang College of Economics and Management Nanjing University of Aeronautics and AstronauticsNanjing211106China Research Center for Soft Energy Science Nanjing University of Aeronautics and AstronauticsNanjing211106China School of Management Wuhan University of TechnologyWuhan430070China Research Institute of Digital Governance and Management Decision Innovation Wuhan University of TechnologyWuhan430070China Huafu Fund Management Co. Ltd.ShanghaiChina

This paper analyses the tail risk contagion of US market implied volatility(USIV)on China's energy futures(CEF)markets,exploring how to utilize operations in the CEF to achieve a safe *** CEF characteristics to simultaneously take both long-/short-positions and engage in long-/short-run investment horizons,this paper defines eight different CEF safe haven attributes to counteract the tail risk of extreme increases in *** trading data from March 2.,2.18,to October 30,2.2.,the empirical results show that,first,in the analysis of the entire sample period,China's coking coal futures can serve as a weak safe haven,aiding long-position investors in mitigating the tail risks associated with US gold and stock market implied *** coal futures also assist short-position investors in countering US stock market implied volatility tail ***,in the sub-period analysis,the safe haven attributes of CEF exhibit strong heterogeneity and asymmetry across different ***,the time span during which CEF exhibits a particular safe haven attribute does not persist for an extended period.

关键词： China's energy futures Safe havenImplied volatility Multi-timescale analysis Cross-quantilogram model

A study that redefines the concept of a well-known orchid–pollinator attraction strategy

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National Science Review 2024年第5期11卷 98-99页

作者： hong Liu Department of Earth and Environment International Center for Tropical Botany Florida International University The Fairchild Tropical Botanic Garden

Zhang and collaborators [1] demonstrated that bees of the genus Ctenoplectra collect oil from the newly reported oilreward orchids of the genera Dendrobium and Galeola in Asia, and that the majority of the bees that carry out this act and pollinate the orchids are male. These are new discoveries with significant implications for biodiversity conservation.

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Optical Microsphere Nano-Imaging:Progress and Challenges

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Engineering 2024年第5期36卷 102-123页

作者： Guangxing Wu Minghui hong Department of Electrical and Computer Engineering National University of SingaporeSingapore 117576Singapore Pen-Tung Sah Institute of Micro-Nano Science and Technology Xiamen UniversityXiamen 361005China Innovation Laboratory for Sciences and Technologies of Energy Materials of Fujian Province(IKKEM) Xiamen 361005China

The optical diffraction effect imposes a radical obstacle preventing conventional optical microscopes from achieving an imaging resolution beyond the Abbe diffraction limit and thereby restricting their usage in a multitude of nanoscale *** the past decade,the optical microsphere nanoimaging technique has been demonstrated to be a cost-effective solution for overcoming the diffraction limit and has achieved an imaging resolution of up to about k6k8 in a real-time and label-free manner,making it highly competitive among numerous super-resolution imaging *** this review,we summarize the underlying nano-imaging mechanisms of the microsphere nanoscope and key advancements aimed at imaging performance enhancement:first,to change the working environment or modify the peripheral hardware of a single microsphere nanoscope at the system level;second,to compose the microsphere compound lens;and third,to engineer the geometry or ingredients of *** also analyze challenges yet to be overcome in optical microsphere nano-imaging,followed by an outlook of this technique.

关键词： Microsphere Nano-imaging Virtual imaging Microsphere compound lens Engineered microsphere

A Denoiser for Correlated Noise Channel Decoding: Gated-Neural Network

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China Communications 2024年第2期21卷 122-128页

作者： Xiao Li Ling Zhao Zhen dai Yonggang Lei School of Electronic and Information Engineering Beihang UniversityBeijing 100191China Beijing Institute of Tracking and Telecommunications Technology BITTT

This letter proposes a sliced-gated-convolutional neural network with belief propagation(SGCNN-BP) architecture for decoding long codes under correlated noise. The basic idea of SGCNNBP is using Neural Networks(NN) to transform the correlated noise into white noise, setting up the optimal condition for a standard BP decoder that takes the output from the NN. A gate-controlled neuron is used to regulate information flow and an optional operation—slicing is adopted to reduce parameters and lower training complexity. Simulation results show that SGCNN-BP has much better performance(with the largest gap being 5dB improvement) than a single BP decoder and achieves a nearly 1dB improvement compared to Fully Convolutional Networks(FCN).

关键词： belief propagation channel decoding correlated noise neural network