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International Applied Computational Electromagnetics Society Symposium (ACES)

作者： Jiaqi Liu Gang Meng Lei Mu Lu Gao Jinjun Mo Runhui Wu Weidong Wang National Key Laboratory of Science and Technology on Test Physics & Numerical Mathematics Beijing China School of Information and Communication Guilin University of Electronic Technology Guilin China

The piecewise linear recursive convolution(PLRC) method based on finite difference time domain(FDTD) is used to calculate the reflection and transmission characteristics of electromagnetic waves from one-dimensional unmagnetized plasma. The results are shown that this method has obvious advantages in accurately calculating the electromagnetic problems of one-dimensional, small-scale and thin-layer dielectric materials.

关键词： Convolution Electromagnetic scattering Dielectric materials Computational electromagnetics Reflection Plasmas Electromagnetics

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A Radiation Pattern-Reconfigurable Patch Antenna with Tunable CSRR based on Liquid Metal and 3-D Printed Microfluidics

A Radiation Pattern-Reconfigurable Patch Antenna with Tunabl...

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International Applied Computational Electromagnetics Society Symposium (ACES)

作者： Yumeng Wang Lu Gao Pei Zheng Lingnan Song School of Electronic and Information Engineering Beihang University Beijing China National Key Laboratory of Science and Technology on Test Physics and Numerical Mathematics Beijing China

In this article, a radiation patternreconfigurable patch antenna with tunable complementary split-ring resonators (CSRR) based on liquid metal (LM) and 3-D printed microfluidics is presented. The antenna is composed of three layers, a top coaxial fed rectangular patch, a middle ground plane with two CSRRs etched symmetrically, and two bottom microfluidics channels each adhered underneath the corresponding CSRR. Pattern reconfiguration is achieved by filling the microfluidic channels with the liquid metal plugs to change the physical parameters of the CSRR structure. By adjusting the length of the slot stubs in CSRRs, the main beam of the double CSRR-loaded antenna can be continuously scanned from -46° to 46° in elevation plane.

关键词： Liquids Slot antennas Patch antennas Simulation Metals Filling Resonators

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UAV Track Planning Algorithm Based on Graph Attention Network and Deep Q Network 11th

UAV Track Planning Algorithm Based on Graph Attention Networ...

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11th International Conference on Image and Graphics, ICIG 2021

作者： Hu, Xinyu Gao, Jingpeng Jiang, Zhiye 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

ISBN: (纸本)9783030873578

To solve the problem that the deviation of the Unmanned Aerial Vehicle (UAV) flight status data collected by the equipment during flight leads to the failure of the mission, this paper proposes a UAV track planning algorithm based on Graph Attention Network and Deep Q Network (DQN). Firstly, we use the camera to collect images and apply pre-trained ResNet to extract image features. Secondly, we adopt the Graph Attention Network to establish the connection between the sensor-measured flight state information and the actual flight state information. Thirdly, we build the optimization model of flight state. Moreover, based on the Deep Reinforcement Learning (DRL) theory, the DQN-based UAV track planning system is trained. Finally, the system combined the optimized flight state to complete the optimal flight action output to realize the track planning. Simulation results show that, compared with the original algorithm which is under the same flight conditions as the proposed algorithm, the velocity deviation rate of the proposed algorithm is improved by 46.79%, which can plan a high-quality track and has good engineering application value. © 2021, Springer Nature Switzerland AG.

关键词： Image processing

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Htem: High-Throughput Toolkit for Elasticity Modeling

SSRN

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SSRN 2025年

作者： Yang, Zhen Xian, Jiawei Xu, Yuanji Lin, De-Ye Wang, Qingchun Gao, Xingyu Tian, Fuyang Song, Haifeng Institute for Applied Physics University of Science and Technology Beijing Beijing100083 China National Key Laboratory of Computational Physics Institute of Applied Physics and Computational Mathematics Beijing100094 China CAEP Software Center for High Performance Numerical Simulation Institute of Applied Physics and Computational Mathematics Beijing100094 China

The elasticity under varying temperatures and pressures is particularly significant for understanding mechanical properties and structural phase transitions. Consequently, there is an increasing demand for tools capable of determining elasticity across wide temperature and pressure ranges, either numerically or analytically. We propose HTEM, a comprehensive toolkit that automates the workflow for input generation, elastic calculations, modeling, and visualization within an integrated framework. HTEM performs simulations with four computational modes, allowing users to balance accuracy and efficiency. It incorporates a semi-analytic model for robust, high-precision elastic modeling with finite data combinations, even using sparse elasticity at high temperatures. To validate the workflows of calculation and modeling, we perform HTEM to study the elasticity of Si across wide temperature and pressure ranges. Results show the high precision and high efficiency of HTEM. And modeling mitigates noise from constant pressure ensemble simulations. Furthermore, HTEM provides detailed visualizations of elasticity and its anisotropy as functions of temperature and pressure, providing comprehensive insights into how the intrinsic properties of materials evolve under varying conditions. © 2025, The Authors. All rights reserved.

关键词： Elasticity

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On the metric resolvent: nonexpansiveness, convergence rates and applications

arXiv

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arXiv 2021年

作者： Xue, Feng National Key Laboratory of Science and Technology on Test Physics and Numerical Mathematics Beijing100076 China

In this paper, we study the nonexpansive properties of metric resolvent, and present a convergence rate analysis for the associated fixed-point iterations (Banach-Picard and Krasnosel’skii-Mann types). Equipped with a variable metric, we develop the global ergodic and non-ergodic iteration-complexity bounds in terms of both solution distance and objective value. A byproduct of our expositions also extends the proximity operator and Moreau’s decomposition identity to arbitrary variable metric. It is further shown that many classes of the first-order operator splitting algorithms, including alternating direction methods of multipliers, primal-dual hybrid gradient and Bregman iterations, can be expressed by the fixed-point iterations of a simple metric resolvent, and thus, the convergence can be analyzed within this unified *** Codes 68Q25, 47H05, 90C25, 47H09 Copyright © 2021, The Authors. All rights reserved.

关键词： Iterative methods

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Real-Time Path Planning based on the Lock Loss Model

Real-Time Path Planning based on the Lock Loss Model

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International Applied Computational Electromagnetics Society Symposium (ACES)

作者： Xun Luo Li Liu Xin Liu National Key Laboratory of Science and Technology on Test Physics & Numerical Mathematical Beijing China China Academy of Launch Vehicle Technology Beijing China

A new method of aircraft low altitude penetration is proposed with temporal constraints that allow periods of high observability interspersed with periods of low observability. The aircraft’s RCS character is simplified into the “bow-tie” distribution, then the aircraft can dynamically adjust its yaw angle to minimize the risk from the radars. According to the modified Lock Loss model and the TWS(Track While Scan) radar work flow, and real-time evaluating model on the original path, a fast real-time path planning method is present on the situation that unexpected threats occur. An example of real-time path planning is given.

关键词： Radar cross-sections Atmospheric modeling Heuristic algorithms Airborne radar Real-time systems Path planning Safety

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A Radar Signal Modulation Recognition Algorithm Based on Multi-branch Fusion Difference

A Radar Signal Modulation Recognition Algorithm Based on Mul...

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

作者： Sisi Jiang Jingpeng Gao Zhiye Jiang Fang Ye College of Information and Communication Engineering Harbin Engineering University Haibin China National Key Laboratory of Science and Technology on Test Physics and Numerical Mathematics Beijing Institute of Space Long March Vehicle Beijing China National Key Laboratory of Underwater Acoustic Technology College of Information and Communication Engineering Harbin Engineering University Harbin China

The time-frequency images of radar modulation signals are similar at low signal-to-noise ratios, which will lead to lower recognition accuracy. This paper proposes an algorithm based on multi-branch fusion differences to identify radar modulation signals. The algorithm designs a multi-branch fusion differential module based on the attention mechanism and differential thinking, to extract time-frequency image fine-grained features and improve the Convolution Neural Network characterization ability. After that, a dual-branch differential network is proposed by combining vanilla convolution and multi-branch fusion difference module. The network can fuse global and detailed features of time-frequency images, which can achieve radar signal modulation recognition. The simulation results show that the recognition accuracy of the algorithm can reach 93.17% at 0dB. Therefore, the algorithm can obtain high recognition accuracy and has high recognition performance.

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Periodic Structures and Its Interaction to EM Wave Spectrum, Ideas From X-Ray to MW Wave

Periodic Structures and Its Interaction to EM Wave Spectrum,...

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International Applied Computational Electromagnetics Society Symposium (ACES)

作者： Yunhui Tang Lu Gao Ruzhi Wang Shengjun Zhang Hang Song Yuning Zhang Xia Ai Lei Xie Luting Jiao Xiaoling Zhang Jing He Jiaqi Liu Beijing University of Technology Beijing China National Key Laboratory of Science & Technology on Test Physics and Numerical Mathematics Beijing China Beijing Institute of Space Long March Vehicle Beijing China

X-ray is an important tool for characterizing materials, which is based on the idea that all crystals are composed of atoms or molecules stacking in a particular type, basically expressing as unit cell, diffracting the incident ray with a proper type. In analogue, the periodic structures which are mostly constructed artificially show special desired properties, such as the properties of grating, frequency selective surfaces, metamaterials and metasurface. In this paper, A study was done on the insight of the relation of wave interaction with periodic structures based on X-ray diffraction and control of electromagnetic waves.

关键词： Frequency selective surfaces Stacking Electromagnetic scattering Crystals X-ray diffraction Metasurfaces Computational electromagnetics

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An Improved DSDV Protocol based on Link Stability with Adaptive Period for Intra-cluster Routing in High-dynamic Flying UAV Networks

An Improved DSDV Protocol based on Link Stability with Adapt...

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International Applied Computational Electromagnetics Society Symposium (ACES)

作者： Yiguo Zhang Lai Qian Xiaoqin Xue Wei Wang College of Computer Science Xi’an Polytechnic University Xi’an China National Key Laboratory of Science and Technology on Test Physics and Numerical Mathematics Beijing Institute of Space Long March Vehicle Beijing China

We propose a stability-based adaptive-period DSDV intra-cluster routing protocol that automatically adjusts the routing update period by the link stability among the nodes in the cluster structure, thus reducing the network overhead of the network structure in maintaining the routing table. We describe the link stability and adaptive period implementation and test the proposed routing protocol in the cluster structure based on network simulation. The implementation results show that the proposed routing protocol has better performance than the traditional DSDV routing protocol, can improve the network throughput and reduce the routing overhead in the network, and has good adaptability in the cluster with fast changing network topology.

关键词： Costs Adaptive systems Network topology Routing Throughput Computational electromagnetics Routing protocols

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Spectral–spatial attention fusion transformer for hyperspectral image classification

Spectral–spatial attention fusion transformer for hyperspec...

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IET International Radar Conference (IRC 2023)

作者： Xiangyu Ji Jingpeng Gao Geng Chen Lu Gao College of Information and Communication Engineering Harbin Engineering University Harbin 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 People's Republic of China

ISBN: (数字)9781837240982

In view of the limited generalization and poor local feature information modeling ability of vision transformer model(ViT) in hyperspectral image classification, a Spectral-Spatial Attention Fusion Transformer (SAFT) method for hyperspectral image classification is proposed in this paper. The proposed method includes two key modules: Spectral-Spatial Feature Extraction Module (SSFE) and Multi-Head Attention Fusion Transformer Module (MAFT). The SSFE module is a lightweight network. It contains a 3D convolution block and a 2D convolution block, which can efficiently obtain local feature information. Based on the proposed attention fusion structure, the MAFT module designs an improved transformer encoder. It improves the generalization ability of the model on the premise of obtaining global information. In this paper, two datasets of HyRANK are used for experiments. The experimental results show that this method is superior to other HSI classification methods.

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