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International Symposium on Antennas, Propagation and EM Theory (ISAPE)

作者： Chi Zhang Sicheng Gao Juntao Cui Tie Li Science and Technology on Electromechanical Dynamic Control Laboratory Xi'an China

ISBN: (数字)9798350353129

ISBN: (纸本)9798350353136

In this paper, a measurement method based on a smoke chamber is proposed to study the backscattering characteristics of pulsed laser fuze in smoke environment. Firstly, the smoke environment was created in a chamber by burning a known amount of smoke agent whose main chemical composition is red phosphorus. Then, a pulsed laser fuze and auxiliary equipments (visibility meters, lambert reflectors, etc) were arranged to collect echo signals. Finally, a statistical method was used to analyze echo characteristics of the pulsed laser fuze. The experimental results show that the laser fuze prototype used in this experiment does not even have the ability to distinguish a target with low reflectivity (5%) from the smoke environment which was created by burning 0.3g smoke agent, and it cannot discriminate a target with high reflectivity (99%) from the smoke environment when the mass of smoke agent is larger than 4g dues to the high smoke particles concentration. The method proposed in this article provides a new feasible means for the research on anti-interference effect evaluation for smoke of pulsed laser fuze.

关键词： Reflectivity Antenna measurements Meters Pulse measurements Atmospheric measurements Statistical analysis Prototypes Particle measurements Phosphorus Laser pulses

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Nonlinear Spline Prioritization Optimization Adaptive Filter

Nonlinear Spline Prioritization Optimization Adaptive Filter

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International Conference on Guidance, Navigation and control, ICGNC 2022

作者： Guo, Wenyan Zhi, Yongfeng Gao, Huan School of Automation Northwestern Polytechnical University Xi’an710129 China Science and Technology on Electromechanical Dynamic Control Laboratory Xi’an710065 China

ISBN: (纸本)9789811966125

The nonlinear spline prioritization optimization adaptive filter (SPOAF) utilized for system identification is proposed to solve the poor steady-state accuracy caused by the mismatched feedback error of the adaptive strategy in spline adaptive filter (SAF). The FIR filter weight is designed to be updated based on the linear error of the linear module. Then, control point is updated according to the error of the whole system. Next, the least mean square algorithm (LMS) and stochastic gradient descent algorithm (SGD) are applied to the nonlinear spline prioritization optimization adaptive filter. Finally, the convergence performance of the proposed SPOAF approach is analyzed. The simulation confirms the effectiveness and efficiency of our proposed SPOAF algorithm. © 2023, The Author(s), under exclusive license to Springer Nature Singapore Pte Ltd.

关键词： Adaptive filters

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Classification Method of Echo and Interference Signal Support Vector Machine Based on Two-Dimensional Characteristic Parameters

Classification Method of Echo and Interference Signal Suppor...

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International Symposium on Antennas, Propagation and EM Theory (ISAPE)

作者： Wei Chen Rui-hu Wen Kai-li Yang Zi-tong Li Gan Zhang Xi-yu Wang Science and Technology on Electromechanical Dynamic Control Laboratory Xi'an China

ISBN: (数字)9798350353129

ISBN: (纸本)9798350353136

In order to improve the anti-jamming ability of FM fuze in electronic countermeasures, a support vector machine classification method for echo signal and jamming signal based on two-dimensional characteristic parameters was proposed. In this method, the actual target echo signal and the guided jamming signal of the frequency modulated fuze are taken as the research objects, and the time domain information entropy and frequency domain information entropy are used as the two-dimensional feature parameters, and the two signals are classified and identified by the support vector machine classification method. Through laboratory tests, it can be seen that the classification accuracy can reach more than 95%.

关键词： Time-frequency analysis Frequency modulation Accuracy Support vector machine classification Vectors Object recognition Jamming Information entropy Time-domain analysis Electronic countermeasures

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Dual-functional Metamaterial Device controlled by a Singular Switch

Dual-functional Metamaterial Device Controlled by a Singular...

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Progress in Electromagnetic Research Symposium (PIERS)

作者： Yongdiao Wen Gang Li Tie Li Science and Technology on Electromechanical Dynamic Control Laboratory Xi’an China

ISBN: (数字)9798350375909

ISBN: (纸本)9798350375916

Herein, a dual-functional terahertz (THz) metamaterial device is presented, the proposed device consists of two heteromorphic arrows, which can switch freely between absorption and polarization conversion controlled by a singular switch. The absorptivity peak (arounds 1.5 THz) and polarization conversion peak (arounds 2.8 THz) will be changed to polarization conversion peak and absorptivity peak with the state of the singular switch, the absorption function and the polarization conversion function can adjust and convert each other, and the maximum values of absorption rate and polarization conversion rate reach to 87.27% and 95.94% respectively.

关键词： Performance evaluation Electric potential Absorption Switches Conductivity control systems Silicon

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Smoke Diffusion Feature Extraction and Concentration Prediction Method Based on Canny Edge Detection

Smoke Diffusion Feature Extraction and Concentration Predict...

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International Symposium on Antennas, Propagation and EM Theory (ISAPE)

作者： Yue Xie Hong Su Tie Li Gang Li Yali Hou Science and Technology on Electromechanical Dynamic Control Laboratory Xi'an China

ISBN: (数字)9798350353129

ISBN: (纸本)9798350353136

In the dynamic intersection scene between laser detector and smoke interference, it is difficult to quantitatively describe the smoke state parameter information of laser detection optical path at different times due to the fluidity and randomness of smoke. This paper proposes a smoke diffusion video feature extraction and concentration prediction method based on Canny edge detection. This method extracts high-speed video of smoke diffusion, detects the edge of the video image and segments the smoke area, analyzes and obtains the corresponding relationship between the shielding effect of smoke diffusion, the number of image pixels in the transmission path and the smoke concentration, By extracting the shielding effect of 1, 2, and 4 typical smoke scenes during diffusion, and analyzing the number of image pixels of a certain transmission path of smoke diffusion, the smoke impact in the dynamic intersection scene of the laser detector and smoke interference is quantified. Subsequently, the laser detector dynamic intersection scene and detection beam parameters can be combined to quantitatively describe the relative position of the laser beam in the smoke transmission path and the concentration state estimation in different forms of smoke scenes, providing important support for the time-correspondence of the echo signal and the optimization of the smoke interference algorithm.

关键词： Laser theory Image edge detection Lasers Interference Detectors Prediction methods Feature extraction Laser beams State estimation Optimization

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Measurement of Millimeter Wave Transmission Characteristics Based on Battlefield Smoke Interference Environment

Measurement of Millimeter Wave Transmission Characteristics ...

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International Symposium on Antennas, Propagation and EM Theory (ISAPE)

作者： Sicheng Gao Chi Zhang Juntao Cui Tie Li Dynamic Control Laboratory Science and Technology on Electromechanical Xi'an China

ISBN: (数字)9798350353129

ISBN: (纸本)9798350353136

In response to the impact of copper powder and smoke interference on millimeter wave transmission characteristics, four band tests were conducted using the same smoke agent equivalent battlefield interference environment, including K-band (24GHz), Ka band (34.5GHz), V-band (61GHz), and F-band (94GHz), to obtain millimeter wave radar echoes and analyze them. The experimental results indicate that: The interference of smoke on millimeter wave transmission has randomness, and as the concentration of smoke increases, the interference ability will gradually become stronger; As the carrier frequency increases, the wavelength gradually shortens and the anti-interference ability gradually improves; Relatively speaking, the interference ability of copper powder on millimeter wave transmission is stronger than that of fine smoke aerosols, but far inferior to that of foil cloud clusters.

关键词： Powders Clouds Wavelength measurement Millimeter wave measurements Transmitting antennas Interference Millimeter wave radar Aerosols Millimeter wave propagation Copper

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RCS Simulation of Partly Coated Electrically Large Target with SBR Method

RCS Simulation of Partly Coated Electrically Large Target wi...

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International Symposium on Antennas, Propagation and EM Theory (ISAPE)

作者： Tiantian Feng Tie Li Gang Li Yongdiao Wen Haijun He Sihan Zhao Science and Technology on Electromechanical Dynamic Control Laboratory Xi'an China

ISBN: (数字)9798350353129

ISBN: (纸本)9798350353136

In this study, radar cross section of electrically large target partly coated with radar absorbing materials has been simulated and analyzed by using shooting and bouncing ray method. First, the simulation results are validated by comparing with multilevel fast multipole method for electrically small objects. Then the radar cross section of electrically large target is calculated and evaluated in three conditions: perfect electric conductor, partly coated and fully coated. The results indicate that part coating plays an equivalent role in a certain range of angles compared with the full coating, which provides a way to reduce cost of coated stealth plane.

关键词： Radar cross-sections Costs Antenna theory Simulation Radar antennas Conductors Radar applications Coatings

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Time-series Data Modeling Guided by Visual Information 11

Time-series Data Modeling Guided by Visual Information

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2023 IEEE 11th International Conference on Information, Communication and Networks, ICICN 2023

作者： Zhang, Ke Wang, Junzheng Zhang, Xiang Shi, Yu Wang, Ting Beijing Institute of Technology School of Automation Beijing China Xi'An Institute of Electron-mechanical Information Technology Science and Technology on Electromechanical Dynamic Control Laboratory Xi'an China

ISBN: (纸本)9798350314014

Time-series data typically contain issues such as missing data and noise, which can impact the model's precision and stability. This paper proposes a Transformer structure-based visual information-guided temporal data modeling algorithm to address the issues as mentioned above. The algorithm effectively captures the time-series structure of the time-series data, thereby enhancing the model's precision and stability. To evaluate the performance of the proposed algorithm, a dataset containing visual information aligned with time-series data is compiled, and a comprehensive quantitative and qualitative analysis is performed. Conduct a comprehensive quantitative and qualitative analysis. The results indicate that visual information can assist time-series data in capturing the intricate dynamics of the time-series data, thereby enhancing the performance of the proposed algorithm and facilitating its comprehension. The results indicate that visual information can assist time-series data in capturing the complex dynamics of time-series data, and thus in comprehending and predicting their behavior and trends. The application of this algorithm will advance research in the field of modeling and predicting time series data. Applying this algorithm will advance research and practice in modeling and forecasting time series data. © 2023 IEEE.

关键词： Time series

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Real-time monitoring and analysis of hydraulic fracturing in surface well using microseismic technology:Case insights and methodological advances

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International Journal of Mining science and technology 2025年第4期35卷 619-638页

作者： Yanan Qian Ting Liu Cheng Zhai Hongda Wen Yuebing Zhang Menghao Zheng Hexiang Xu Dongyong Xing Xinke Gan State Key Laboratory of Coal Mine Disaster Prevention and Control China University of Mining and TechnologyXuzhou 221116China Yunlong Lake Laboratory of Deep Underground Science and Engineering Xuzhou 221003China Key Laboratory of Theory and Technology on Coal and Rock Dynamic Disaster Prevention and Control National Mine Safety AdministrationChina University of Mining and TechnologyXuzhou 221116China School of Safety Engineering China University of Mining and TechnologyXuzhou 221116China School of Emergency Management Chengdu UniversityChengdu 610106China School of Safety Science and Engineering Anhui University of Science and TechnologyHuainan 232001China Xinjiang Yaxin Coalbed Methane 156 Exploration Co. Ltd.Urumqi 841100China

Through a case analysis,this study examines the spatiotemporal evolution of microseismic(MS)events,energy characteristics,volumetric features,and fracture network development in surface well hydraulic fracturing.A total of 349 MS events were analyzed across different fracturing sections,revealing significant heterogeneity in fracture *** scanning results showed that cumulative energy values ranged from 240 to 1060 J across the sections,indicating notable *** reservoir volume(SRV)analysis demonstrated well-developed fracture networks in certain sections,with a total SRV exceeding 1540000 m^(3).The hydraulic fracture network analysis revealed that during the midfracturing stage,the density and spatial extent of MS events significantly increased,indicating rapid fracture propagation and the formation of complex *** the later stage,the number of secondary fractures near fracture edges decreased,and the fracture network *** comparing the branching index,fracture length,width,height,and SRV values across different fracturing sections,Sections No.1 and No.8 showed the best performance,with high MS event densities,extensive fracture networks,and significant energy ***,Sections No.4 and No.5 exhibited sparse MS activity and poor fracture connectivity,indicating suboptimal stimulation effectiveness.

关键词： Hydraulic fracturing Microseismic Source location Energy scanning Fracture network

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Research on weak signal detection based on wavelet-correlation detection algorithm 4

Research on weak signal detection based on wavelet-correlati...

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4th International Conference on Digital Signal and Computer Communications, DSCC 2024

作者： Cheng, Biyao Li, Ming Wang, Xiaozhuo Science and Technology on Electromechanical Dynamic Control Laboratory Xi’an710065 China Xi’an Institute of Electromechanical Information Technology Xi’an710065 China School of Astronautics Northwestern Polytechnical University Xi'an710072 China

ISBN: (纸本)9781510681538

The detection of weak signals has a wide range of applications in engineering. In this paper, a combined algorithm of wavelet transform and correlation detection is proposed to address the problems in current detection methods, namely the wavelet-correlation detection algorithm, to detect weak signals. By building a Simulink model on Matlab and implementing simulation through programming, the reliability of the algorithm is verified. The detection performance of the algorithm for weak signals in fixed noise and color noise environments is analyzed, and compared with the cross-correlation detection method. The results show that the wavelet-correlation detection algorithm can distinguish weak signal features from strong noise backgrounds. Taking the 5.2943dB input signal as an example, the wavelet- correlation detection algorithm improves the relative error of amplitude from 1.89% to 0.35%. Signal-to-noise ratio increased by 8.7638dB. © 2024 SPIE.

关键词： Wavelet transforms

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