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IEEE International Conference on Electronic Information and Communication technology (ICEICT)

作者： Chen Shen Jingpeng Gao Zhiye Jiang Tianran Zhang Geng Chen College of Information and Communication Engineering Harbin Engineering University Harbin China National Key Laboratory of Science and Technology on Test Physics and Numerical Mathematics Beijing Institute of Space Long March Vehicle Beijing China Beijing Institute of Electronic System Engineering Beijing China

In the context of non-cooperative electronic countermeasures, the problem of formulating effective jamming task assignments arises due to insufficient collaborative jamming resources. This paper proposes a binary sparrow- hybridized beluga whale optimization algorithm based on jamming task assignments. The algorithm combines the binary sparrow search algorithm(BSSA) and the binary beluga whale optimization(BBWO), which is set with multi-dimensional constraints in the time, frequency and spatial domains. To achieve the optimal strategy for collaborative interference task assignment, a fitness function is constructed using both radar coverage and the signal-to-jamming ratio received by each radar. When the number of UAVs is 7 and the number of radars is 10, the simulation results show that the optimization speed and accuracy of the proposed algorithm are significantly higher than the BSSA and BBWO. Therefore, the algorithm has good coverage and performance in the field of jamming task assignments.

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Intra-pulse modulation feature analysis and parameter estimation of phase and frequency multi-modulation signal

Intra-pulse modulation feature analysis and parameter estima...

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IET International Radar Conference (IRC 2023)

作者： Chenle Xue Zhiye Jiang Lixiang Ren Huayu Fan Quanhua Liu Radar Research Lab School of Information and Electronics Beijing Institute of Technology Beijing 100081 People's Republic of China National Key Laboratory of Science and Technology on Test Physics and Numerical Mathematics Beijing Institute of Space Long March Vehicle Beijing 100076 People's Republic of China

ISBN: (数字)9781837240982

The parameter inversion of multi-modulation waveforms has always been a key and difficult problem in the field of electronic reconnaissance. To solve this problem, a method for intra-pulse modulation feature analysis and parameter estimation of phase and frequency multi-modulation signal is proposed in this paper. Firstly, we apply square preprocessing to eliminate the binary phase coded modulation information. Then, subpulse separation and subpulse parameter estimation are achieved by using the smooth pseudo-Wigner Ville distribution (SPWVD) and wavelet transform. Moreover, histogram statistics are introduced to improve the robustness of the method. Finally, the N-order phase difference is proposed for recovering binary phase coded sequences. Frequency domain filtering and sliding window averaging are also added to further improve the applicability of the proposed method under low signal-to-noise ratio (SNR) conditions. Simulation results suggest that the method proposed in this paper can achieve accurate signal inversion and has good robustness.

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Intercept Strategy for Maneuvering Target Based on Deep Reinforcement Learning

Intercept Strategy for Maneuvering Target Based on Deep Rein...

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第40届中国控制会议

作者： Xu Wang Yuanli Cai Yizhong Fang Yifan Deng School of Automation Science and Engineering Xi'an Jiaotong University National Key Laboratory of Science Technology on Test Physics & Numerical Mathematics

A novel interception strategy for high-speed maneuvering target based on reinforcement learning（RL） algorithm is proposed. With reshaped reward function and observation consisting solely of relative position information and path angle, the interception policy is trained by Deep Deterministic Policy Gradient（DDPG） algorithm. The results of training and test indicate that the proposed guidance law can approximate the optimal control model of the maneuvering target interception and show the superiority over traditional method.

关键词： Exoatmospheric Interception Maneuvering Target Deep Reinforcement Learning DDPG

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Evaluation of multidimensional simulations of summer air temperature in China from CMIP5 to CMIP6 by the BCC models: From trends to modes

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Advances in Climate Change Research 2022年第1期13卷 28-41页

作者： Yun-Wen LIU Liang ZHAO Gui-Rong TAN Xin-Yong SHEN Su-Ping NIE Qing-Quan LI Li ZHANG Key Lciboratoiy of Meteorological Disaster Ministry of EducationJoint International Research Laboratory'of Climate and Environment ChangeCollaborative Innovation Center on Forecast and Evaluation of Meteorological DisastersNanjing University of Information Science and TechnologyNanjing 210044China State Key Laboratory of Numerical Modeling for Atmosphere Sciences and Geophysical Fluid Dynamics(LASG) Institute of Atmospheric PhysicsChinese Academy of SciencesBeijing 100029China Southern Marine Science and Engineering Guangdong Laboratory(Zhuhai) Zhuhai 519082China Laboratory for Climate Studies National Climate CenterChina Meteorological AdministrationBeijing 100081China

To determine whether the capability of the CMIP6 version of Beijing Climate Center(BCC)models(BCC-ESMI and BCC-CSM2-MR)in simulating China summer surface air temperature(SAT)has improved,we presented a multidimensional evaluation of the summer SAT in China including the trends,modes,and influencing *** comparisons are also made with the results of CMIP5(BCC-CSM1.1 and ***).In general,the CMIP6,especially BCC-CSM2-MR,has smaller deviations in the trends,the means,the mutations,the maximum centers,the variances,and the spatial patterns of the dominant modes from observatio relative to those of ***,the BCC CMIP6 models still underestimate the SAT variation in the Qinghai-Tibetan Plateau and the northeastern regions of China,and the performance is unsatisfactory with respect to the physical drivers of the dominant ***,all the BCC models can capture the spatio-temporal characteristics of the first mode well and can,in general,characterize the spatial pattern of the second mode,but none of the models perform well in the principal component of the second mode(PC2)due to the low performance with respect to the interannual variation of ***,the factors influencing the leading two modes are *** two CMIP6 can simulate better the Northern Hemisphere subtropical high northern boundary affecting the first *** factor,the Asia polar vortex area,can only be simulated better by two low-resolution models(BCC-CSM1.1 and BCC-ESM I).For the second mode,all four models simulate the influence of Asian zonal circulation well,but poorly simulate that of the southern Indian Ocean dipole due to a large deviation in the Indian Ocean surface temperature.

关键词： Summer mean temperature China Dominant mode CMIP6 BCC

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DFT study of elastic, structural, and optical properties of K2InAgZ6 (Z = Cl, Br, I) perovskites: potential for optoelectronic applications

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Optical and Quantum Electronics 2024年第12期56卷 1-17页

作者： Ahmad, Sohail Zakria, Muhammad Alotaibi, Khalid M. Huma, Tabasum Hakimi, Nadimullah Ali, Rawaid Qasimullah Safeen, Akif Feng, Jing Shah, Syed Hatim Faculty of Materials Science and Engineering Kunming University of Science and Technology Kunming650093 China Pakistan Institute of Engineering and Applied Sciences National Institute of Lasers and Optronics College Nilore Islamabad45650 Pakistan Department of Chemistry Collage of Science King Saud University PO Box 2455 Riyadh11541 Saudi Arabia Faculty of Metallurgical and Energy Engineering Kunming University of Science and Technology Kunming650093 China College of Physical and Electronic Information Technology Key Laboratory of Advanced Techniques for Renewable Energy Materials Ministry of Education Yunnan Normal University Kunming650500 China Faculty of Physical and Numerical Sciences Qurtuba University of Science and Information Technology Peshawar Peshawar25100 Pakistan Department of Physics University of Poonch Rawalakot AJK Poonch12350 Pakistan

In this article, a comprehensive research was carried out to investigate the elastic, structural, and optoelectronic properties of double perovskite compounds K2InAgCl6, K2InAgBr6, and K2InAgI6 by using density functional theory. Goldsmith’s tolerance factor (tG), whose values are near to unity, was used to assess the structural stability of the cubic perovskite structure. According to the analysis of electronic characteristic, K2InAgCl6, K2InAgBr6, and K2InAgI6 are semiconductors with a tiny band gap, calculated using the mBJ-PBE sol potential with band gap values of 2.48 eV, 1.47 eV, and 0.23 eV, respectively. A comprehensive analysis of the optical characteristics of these compounds was conducted across an energy range from 0 to 10 eV. The results revealed that K2InAgCl6, K2InAgBr6, and K2InAgI6 exhibit significant conductivity and absorbance properties in wide energy ranges, which is confirmed by density of states analysis. Moreover, the optical characteristics shows that lower photon energy relates to high optical transmission, while higher energies result in more optical absorption of material. These results demonstrate that K2InAgCl6, K2InAgBr6, and K2InAgI6 are viable material candidates for use in high-frequency UV optical devices. © The Author(s), under exclusive licence to Springer science+Business Media, LLC, part of Springer Nature 2024.

关键词： Perovskite

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Sparse Conformal Array Synthesis Based on Multiagent Genetic Algorithm

Sparse Conformal Array Synthesis Based on Multiagent Genetic...

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IEEE Asia-Pacific Conference on Antennas and Propagation (APCAP)

作者： Ganyu Liu Hailiang Zhu Kai Wang Jinchao Mou Pei Zheng Gao Wei Northwestern Polytechnical University School of Electronics and Information Xi'an Shaanxi CN Beijing Research Institute of Telemetry Beijing CN The National Key Laboratory of Science and Technology on Test Physics and Numerical Mathematics Beijing CN

In this paper, multiagent genetic algorithm (MAGA) is firstly applied to tackle the synthesis of conformal sparse array, a constrained multi-objective optimization problem. Moreover, a model considered low peak sidelobe level (PSLL) is given for conformal sparse array synthesis. For the antenna array deployed on a quadric surface, the PSLL can be reduced by obtaining the optimal antenna element arrangement. An example of 256-element array synthesis with a 56% sparse rate proves MAGA as an effective optimization tool for conformal sparse arrays in low computational cost.

关键词： Computational efficiency Optimization Genetic algorithms Antenna arrays

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Factors contributing to rapid decline of Arctic sea ice in autumn

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Advances in Polar science 2021年第2期32卷 96-104页

作者： LI Shuyao CUI Hongyan XU Junli GONG Xiang QIAO Fangli YANG Yanzhao WANG Ping HAN Yuqun SHAN Feng College of Mathematics and Physics Qingdao University of Science and TechnologyQingdao 266061China Research Institute for Mathematics and Interdisciplinary Sciences Qingdao University of Science and TechnologyQingdao 266061China Laboratory for Regional Oceanography and Numerical Modeling Qingdao National Laboratory for Marine Science and TechnologyQingdao 266061China The First Institute of Oceanography Ministry of Natural ResourcesQingdao 266061China

Autumn Arctic sea ice has been declining since the beginning of the era of satellite sea ice *** this study,we examined the factors contributing to the decline of autumn sea ice *** the Beaufort Sea to the Barents Sea,autumn sea ice concentration has decreased considerably between 1982 and 2020,and the rates of decline were the highest around the Beaufort *** calculated the correlation coefficients between sea ice extent(SIE)anomalies and anomalies of sea surface temperature(SST),surface air temperature(SAT)and specific humidity(SH).Among these coefficients,the largest absolute value was found in the coefficient between SIE and SAT anomalies for August to October,which has a value of−*** second largest absolute value was found in the coefficient between SIE and SH anomalies for September to November,which has a value of−*** the correlation coefficients between SIE and SST anomalies,the largest absolute value was found in the coefficient for August to October,which has a value of−*** conducted empirical orthogonal function(EOF)analyses of sea ice,SST,SAT,SH,sea level pressure(SLP)and the wind field for the months where the absolute values of the correlation coefficient were the *** first EOFs of SST,SAT and SH account for 39.07%,63.54%and 47.60%of the total variances,respectively,and are mainly concentrated in the area between the Beaufort Sea and the East Siberian *** corresponding principal component time series also indicate positive *** first EOF of SLP explains 41.57%of the total *** is mostly negative in the central *** the Beaufort,Chukchi and East Siberian seas,the zonal wind weakened while the meridional wind *** from the correlation and EOF analyses further verified the effects of the ice-temperature,ice-SH and ice-SLP feedback mechanisms in the *** mechanisms accelerate melting and decrease the rate of formation of sea *** addition,stronger m

关键词： Arctic sea ice rapid decline empirical orthogonal function feedback mechanisms

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Individual Identification Algorithm of Known Emitters Based on Lightweight Binary Channels Neural Network

Individual Identification Algorithm of Known Emitters Based ...

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IEEE International Symposium on Information (IT) in Medicine and Education, ITME

作者： Jingpeng Gao Xia Song Lu Gao College of Information and Communication Engineering Harbin Engineering University Harbin China National Key Laboratory of Science and Technology on Test Physics and Numerical Mathematics Beijing Institute of Space Long March Vehicle Beijing China

Aiming at the problem that the traditional specific emitter identification method has poor feature extraction ability and limited recognition effect, this paper proposes a known specific emitter identification algorithm based on the LBCNet (the Lightweight Binary Channels Net). The algorithm uses bispectrum and cyclic spectrum to highlight the unintentional information in the pulse. Then, it combines the idea of depthwise separable convolution to design the LBCNet to realize adaptive feature extraction, fusion, and classification. Finally, it integrates the attention mechanism to highlight the effective information of the image, enhance the neural network’s learning ability and improve the identification performance of specific emitters. The simulation results show that the recognition rate of the proposed algorithm is as high as 94.53% at 0dB, which has good engineering practical value and can be applied to the field of electronic reconnaissance.

关键词： Convolution Simulation Neural networks Education Radar Reconnaissance Feature extraction

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Effects of Dropsonde Data in Field Campaigns on Forecasts of Tropical Cyclones over the Western North Pacific in 2020 and the Role of CNOP Sensitivity

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Advances in Atmospheric sciences 2023年第5期40卷 791-803页

作者： Xiaohao QIN Wansuo DUAN Pak-Wai CHAN Boyu CHEN Kang-Ning HUANG State Key Laboratory of Numerical Modeling for Atmospheric Sciences and Geophysical Fluid Dynamics Institute of Atmospheric PhysicsChinese Academy of SciencesBeijing 100029China Collaborative Innovation Center on Forecast and Evaluation of Meteorological Disasters Nanjing University of Information Science and TechnologyNanjing 210044China Hong Kong Observatory Hong KongChina Weather Forecasting Office National Meteorological CenterChina Meteorological AdministrationBeijing 100081China Research and Development Center Central Weather BureauTaipei 100006China

Valuable dropsonde data were obtained from multiple field campaigns targeting tropical cyclones,namely Higos,Nangka,Saudel,and Atsani,over the western North Pacific by the Hong Kong Observatory and Taiwan Central Weather Bureau in *** conditional nonlinear optimal perturbation(CNOP)method has been utilized in real-time to identify the sensitive regions for targeting observations adhering to the procedure of real-time field campaigns for the first *** observing system experiments were conducted to evaluate the effect of dropsonde data and CNOP sensitivity on TC forecasts in terms of track and intensity,using the Weather Research and Forecasting *** is shown that the impact of assimilating all dropsonde data on both track and intensity forecasts is ***,assimilation using only the dropsonde data inside the sensitive regions displays unanimously positive effects on both the track and intensity forecast,either of which obtains comparable benefits to or greatly reduces deterioration of the skill when assimilating all dropsonde ***,these results encourage us to further carry out targeting observations for the forecast of tropical cyclones according to CNOP sensitivity.

关键词： tropical cyclones targeting observation field campaign CNOP sensitivity dropsonde intensity forecasts

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The Effects of Base Shape on Cone Scattering Feature

The Effects of Base Shape on Cone Scattering Feature

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International Applied Computational Electromagnetics Society Symposium (ACES)

作者： Yongtao Shui Shengjun Zhang Hang Song Lei Mu Xianglin Zhang Yuning Zhang Yichun Cui Weidong Wang Mingliang Wang Ligen Cai Yinfang Xu Song Chai Jiaqi Liu Chao Dong Fengju Wang Zhengyu Yong Chunshou Shao Minghao Wang Zhaohui Qi Yuan Sun Chenxin Sun Beijing Institute of Space Long March Vehicle Beijing China National Key Laboratory of Science & Technology on Test Physics and Numerical Mathematics Beijing China Institute of Survival Technology effectiveness Evaluation of Flying Vehicle Beijing China

Recent days, radar cross section reduction(RCSR) of objects have attracted much interest as more and more wideband radar were used to detect low observable weapon platforms. Among the low observation technologies, shaping plays an important role. This paper focused on the effect of basement shape on the scattering of a cone-like object, and some basement shape better for low radar cross section design for around tip incident angle were analyzed.

关键词： Geometry Radar cross-sections Shape Surface waves Weapons Electromagnetic scattering Nose

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