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Multicomponent Seismic Data Reconstruction via Anti-Aliasing Vector POCS Method

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Journal of Earth Science 2024年第4期35卷 1385-1392页

作者： Fan Li Jianjun Gao Yun Wang Chunming Wang Sian Hou school of Geophysics and information Technology China University of GeosciencesBeijing 100083China Research Institute of Petroleum exploration and Development Petro ChinaBeijing 100083China

0 INTRODUCTION Due to the ability to comprehensively utilize P and S wave information,multi-component seismic exploration has already played an important role in fracture detection,lithology prediction,fluid identification,etc.,and it has also become an important technology for complex reservoir exploration(Yuan et al.,2021;Stewart et al.,2003).

关键词： reservoir Seismic prediction

Study on Coded Permutation Entropy of Finite Length Gaussian White Noise Time Series

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Chinese Journal of Electronics 2024年第1期33卷 185-194页

作者： Huihui SUN Xiaofeng ZHANG school of Physics and information Technology Shaanxi Normal University

As an extension of permutation entropy(PE), coded permutation entropy(CPE) improves the performance of PE by making a secondary division for ordinal patterns defined in PE. In this study, we provide an exploration of the statistical properties of CPE using a finite length Gaussian white noise time series theoretically. By means of the Taylor series expansion, the approximate expressions of the expected value and variance of CPE are deduced and the Cramér-Rao low bound(CRLB) is obtained to evaluate the performance of the CPE estimator. The results indicate that CPE is a biased estimator, but the bias only depends on relevant parameters of CPE and it can be easily corrected for an arbitrary time series. The variance of CPE is related to the encoding patterns distribution,and the value converges to the CRLB of the CPE estimator when the time series length is large enough. For a finitelength Gaussian white noise time series model, the predicted values can match well with the actual values, which further validates the statistic theory of CPE. Using the theoretical expressions of CPE, it is possible to better understand the behavior of CPE for most of the time series.

关键词： Time series analysis White noise Predictive models Taylor series Entropy Encoding Time measurement

Generic and flexible self-correction method for nonlinearity-induced phase error in three-dimensional imaging

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Chinese Optics Letters 2024年第6期22卷 129-135页

作者： Jianhua Wang Peng Xu Yanxi Yang school of information and Control Engineering Qingdao University of TechnologyQingdao 266520China school of Automation and information Engineering Xi’an University of TechnologyXi’an 710048China

In three-dimensional imaging employing phase-shifting profilometry(PSP), the nonlinear response of projector and camera makes the fringe gray distribution non-sinusoidal, which further leads to phase error. Although the double 3-step phaseshifting method is simple and effective, it needs to add an additional set of fringe sequences, which reduces the measurement efficiency. To this end, this paper introduces a generic and flexible self-correction method for nonlinearity-induced phase ***, according to the nonlinearity-induced phase error model, we introduce an additional wrapped phase with a phase difference of π/3. The error waveform of the two wrapped phases is opposite but not coincident. Then, we introduce an estimation algorithm for the additional wrapped phase offset. Finally, we fuse the two wrapped phases to correct the phase error. Experiments confirm that the root mean squared error of the proposed method is 64.1% lower than that of the traditional method and 13.3% lower than that of the Hilbert transform method. The proposed method does not require any additional fringes or hardware assistance and can be easily extended to 4.step or 5-step PSP.

关键词： three-dimensional imaging phase-shifting profilometry nonlinear response self-correction Hilbert transform

An Analytical Method for Delineating Feasible Region for PV Integration Capacities in Net-zero Distribution Systems Considering Battery Energy Storage System Flexibility

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Journal of Modern Power Systems and Clean Energy 2024年第2期12卷 475-487页

作者： Shida Zhang Shaoyun Ge Hong Liu Guocheng Hou Chengshan Wang school of Electrical and information Engineering Tianjin UniversityTianjin 300072China

To provide guidance for photovoltaic(PV)system integration in net-zero distribution systems(DSs),this paper proposes an analytical method for delineating the feasible region for PV integration capacities(PVICs),where the impact of battery energy storage system(BESS)flexibility is ***,we introduce distributionally robust chance constraints on network security and energy/carbon net-zero requirements,which form the upper and lower bounds of the feasible ***,the formulation and solution of the feasible region is *** resulting analytical expression is a set of linear inequalities,illustrating that the feasible region is a polyhedron in a high-dimensional space.A procedure is designed to verify and adjust the feasible region,ensuring that it satisfies network loss constraints under alternating current(AC)power *** studies on the 4.bus system,the IEEE 33-bus system,and the IEEE 123-bus system verify the effectiveness of the proposed *** is demonstrated that the proposed method fully captures the spatio-temporal coupling relationship among PVs,loads,and BESSs,while also quantifying the impact of this relationship on the boundaries of the feasible region.

关键词： Net-zero distribution system photovoltaic(PV)integration capacity feasible region battery energy storage system(BESS).

Rapid Phase Ambiguity Elimination Methods for DOA Estimator via Hybrid Massive MIMO Receive Array

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Chinese Journal of Electronics 2024年第1期33卷 175-184页

作者： Xichao ZHAN Zhongwen SUN Feng SHU Yiwen CHEN Xin CHENG Yuanyuan WU Qi ZHANG Yifan LI Peng ZHANG school of information and Communication Engineering Hainan University school of Electronic and Optical Engineering Nanjing University of Science and Technology

For a sub-connected hybrid multiple-input multiple-output(MIMO) receiver with K subarrays and N antennas, there exists a challenging problem of how to rapidly remove phase ambiguity in only single time-slot. A direction of arrival(DOA) estimator of maximizing received power(Max-RP) is proposed to find the maximum value of K-subarray output powers, where each subarray is in charge of one sector, and the center angle of the sector corresponding to the maximum output is the estimated true DOA. To make an enhancement on precision, Max-RP plus quadratic interpolation(Max-RP-QI) method is designed. In the proposed Max-RP-QI, a quadratic interpolation scheme is adopted to interpolate the three DOA values corresponding to the largest three receive powers of *** achieve the Cramer Rao lower bound, a Root-MUSIC plus Max-RP-QI scheme is developed. Simulation results show that the proposed three methods eliminate the phase ambiguity during one time-slot and also show low computational complexities. The proposed Root-MUSIC plus Max-RP-QI scheme can reach the Cramer Rao lower bound,and the proposed Max-RP and Max-RP-QI are still some performance losses 2–4.d B compared to the Cramer Rao lower bound.

关键词： Phased arrays Interpolation Wireless sensor networks Direction-of-arrival estimation Simulation Receiving antennas Massive MIMO

Superior Mechanical Behavior and Flame Retardancy FRP via a Distribution Controllable 1D/2D Hybrid Nanoclay Synergistic Toughening Strategy

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Engineering 2024年第9期40卷 166-178页

作者： Zixuan Chen Tianyu Yu Zetian Yang Zhibiao Wei Yan Li Weidong Yang Tao Yu school of Aerospace Engineering and Applied Mechanics Tongji UniversityShanghai 200092China school of Mechanical Engineering University of Shanghai for Science and TechnologyShanghai 200093China Shanghai Suochen information Technology Co. Ltd.Shanghai 200030China Shanghai Key Laboratory of Space Mapping and Remote Sensing for Planetary exploration Tongji UniversityShanghai 200092China

The incorporation of commercial flame retardants into fiber-reinforced polymer(FRP)composites has been proposed as a potential solution to improve the latter’s poor flame ***,this approach often poses a challenge,as it can adversely affect the mechanical properties of the ***,balancing the need for improved flame resistance with the preservation of mechanical integrity remains a complex issue in FRP *** this critical concern,this study introduces a novel additive system featuring a combination of one-dimensional(1D)hollow tubular structured halloysite nanotubes(HNTs)and two-dimensional(2D)polygonal flake-shaped nano kaolinite(NKN).By employing a 1D/2D hybrid kaolinite nanoclay system,this research aims to simultaneously improve the flame retardancy and mechanical *** innovative approach offers several *** combustion and pyrolysis processes,the 1D/2D hybrid kaolinite nanoclay system proves effective in reducing heat release and volatile ***,the system facilitates the formation of reinforcing skeletons through a crosslinking mechanism during pyrolysis,resulting in the development of a compact char *** char layer acts as a protective barrier,enhancing the material’s resistance to heat and *** terms of mechanical properties,the multilayered polygonal flake-shaped 2D NKN plays a crucial role by impeding the formation of cracks that typically arise from vulnerable areas,such as adhesive phase ***,the 1D HNT bridges these cracks within the matrix,ensuring the structural integrity of the composite *** an optimal scenario,the homogeneously distributed 1D/2D hybrid kaolinite nanoclays exhibit remarkable results,with a 51.0%improvement in mode II fracture toughness(GIIC),indicating increased resistance to crack *** addition,there is a 34.5%reduction in total heat release,signifying improved flame *** study represents a significant step

关键词： 1D/2D nanoclays Hierarchical distribution Flame retardancy Fiber-reinforced polymer Damage mechanism

Real-time UWOC miniaturized system based on FPGA and LED arrays and its application in MIMO

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Chinese Optics Letters 2024年第2期22卷 70-75页

作者：黄安殷洪玺梁彦军王建英沈众卫 school of information and Communication Engineering Dalian University of TechnologyDalian 116024China

In order to alleviate the impact of turbulence on the performance of underwater wireless optical communication(UWOC)in real time,and achieve high-speed real-time transmission and low cost and miniaturization of equipment,a 2×2 real-time multiple-input and multiple-output(MIMO)high-speed miniaturized UWOC system based on a field-programmable gate array(FPGA)and a high-power light-emitting diode(LED)array is designed in this *** terms of multiplexing gain,the imaging MIMO spatial multiplexing and high-order modulation for the first time are combined and the real-time high-speed transmission of PAM-4.signal based on the LED array light source in 12 m underwater channel at 100 Mbps rate is implemented,which effectively improves the throughput of the UWOC system with a high-power commercial LED light *** light of diversity gain,the system employs the diversity of repeated coding scheme to receive two identical non-return-to-zero on-off keying(NRZ-OOK)signals,which can compensate the fading or flickering sublinks in real time under the bubble-like simulated turbulence condition,and has high *** our knowledge,this is the first instance of a high rate and long-distance implementation of a turbulence-resistant real-time MIMO miniaturized UWOC system based on FPGA and high-power LED *** spatial diversity or spatial multiplexing capabilities,its low cost,integrity,and high robustness provide the system with important practical prospects.

关键词： underwater wireless optical communication MIMO spatial diversity spatial multiplexing

Mechanical and magnetocaloric adjustable properties of Fe3O4.PET deformed nanoparticle film

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Chinese Physics B 2024年第3期33卷 589-595页

作者：范凤国段林彤 school of Physics and Electrical information Shangqiu Normal UniversityShangqiu 476000China

The flexibility of nanoparticle films is a topic of rapidly growing interest in both scientific and engineering researches due to their numerous potential applications in a broad range of wearable electronics and biomedical *** article presents the elucidation of the properties of nanoparticle ***,a flexible film is fabricated based on polyethylene terephthalate(PET)and magnetic iron oxide at the nanoscale using layer-by-layer *** 2D thin flexible film material can be bent at different angles from 0°to 360°.With an increase in elastic deformation angles,the magnetocaloric effect of the film gradually increases in the alternating magnetic *** test results from a vibrating sample magnetometer and a low-frequency impedance analyzer demonstrate that the film has a good magnetic response and *** magnetocaloric effect and magnetic induction effect are controlled by deformation,providing a new idea for the application of elastic *** combines the flexibility of the nanoparticle PET substrate and,in the future,it may be used for skin adhesion for administration and magnetic stimulation control.

关键词： nanoparticle film deformation magnetic properties flexible substrates

Realization of Quantum Secure Direct Communication with Continuous Variable

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Research 2024年第2期6卷 159-170页

作者： Zhengwen Cao Yuan Lu Geng Chai Hao Yu Kexin Liang Lei Wang school of information Science and Technology Northwest UniversityXi'an710127China

With the progress of theoretical and applied technologies,the communication system based on the classical encryption is seriously threatened by quantum computing and distributed computing.A communication method that directly loads confidential information on the quantum state,quantum secure direct communication(QSDC),came into being for resisting security ***,we report the first continuous-variable QSDC(CV-QSDC)experimental demonstration for verifying the feasibility and effectiveness of the CV-QSDC protocol based on Gaussian mapping and propose a parameter estimation for signal classification under the actual *** our experiment,we provided 4.10^(2) blocks,where each block contains 105 data for direct information *** the transmission distance of 5 km in our experiment,the excess noise is 0.0035 SNU,where SNU represents the unit of shot-noise *** 4.08×10^(5) bit per second experimental results firmly demonstrated the feasibility of CV-QSDC under the fiber *** proposed grading judgment method based on parameter estimation provides a practical and available message processing scheme for CV-QSDC in a practical fiber channel and lays the groundwork for the grading reconciliation.

关键词： quantum estimation verify