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Exploration of the application of optimisation algorithm using stochastic gradient descent method in satellite resource allocation

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Applied Mathematics and Nonlinear sciences 2024年第1期9卷

作者： Zhao, Demin Xiong, Wei Shi, Jinjing Science and Technology on Complex Electronic System Simulation Laboratory University of Aerospace Engineering Beijing101400 China Dfh Satellite CO. Ltd Beijing100080 China North Automatic Control Technology Institute Shanxi Taiyuan030006 China

With the popularization and development of communication technology, the resource allocation problem of satellites has become a hot research topic. This study proposes a model for satellite resource allocation through the development of a beam mobilization system model and problem modeling. Then, on the basis of the linear stochastic gradient descent method, the classification accuracy of the algorithm is improved by adjusting the algorithm-solving method. Then its weight assignment method is improved to get the improved weighted linear stochastic gradient descent method. Using the optimized weighted linear stochastic gradient descent method to solve the satellite resource allocation problem from the perspective of the original problem, a model based on IWLSGD is designed and tested for performance. Through simulation experiments, the beam allocation service value of the satellite resource allocation model in this paper is 193, which is 4.32% and 3.21% higher than that of LSGD and WLSGD, respectively, and iterative convergence is faster, and its operation time and service value performs the best under different numbers of communication time slots. The system revenue, system access success rate, and system satisfaction under the interference environment between LEO and GEO are maintained at 15208, 0.8~1.0, and 85%, and keep around 7500, 1, and 75% under 5G base station interference. The satellite resource allocation model in this paper can effectively improve the utilization efficiency of communication resources and better adapt to dynamically changing interference scenarios. © 2024 Demin Zhao et al., published by Sciendo.

关键词： Resource allocation

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Measurement-based Path Loss Prediction and Analysis in Water Scenarios

Measurement-based Path Loss Prediction and Analysis in Water...

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2024 IEEE International Conference on Computational Electromagnetics, ICCEM 2024

作者： Li, Hanpeng Chen, Xiaomin Li, Hangang Ma, Jian Ye, Xuchao Song, Lixin Zhang, Taotao Zhong, Weizhi Zhu, Qiuming Nanjing University of Aeronautics and Astronautics College of Electronic and Information Engineering Nanjing211106 China Aviation Key Laboratory of Science and Technology On Aero Electromechanical System Integration Nanjing211106 China State Key Lab. of Complex Electromagnetic Environment Effects On Electronics and Information System Luoyang471003 China

ISBN: (纸本)9798350383317

Unmanned aerial vehicles (UAVs) have enabled the unmanned management of water areas. Path loss (PL) serves as a critical factor that affects the UAV communication quality. In this work, a PL model for UAV channel in water scenarios is proposed, aiming to explore the multidimensional relationship between transceiver distance, carrier frequency, UAV height, and PL by constructing an Artificial Neural Network (ANN). Moreover, channel measurements are conducted in a river area, and the obtained data are analyzed using the proposed ANN model as well as the close-in (CI) model. The analysis results demonstrates that the PL increases initially and then declines as the UAV height increases. The proposed ANN model has higher prediction accuracy than the classic empirical model, and can achieve precise prediction of the PL in water scenarios. © 2024 IEEE.

关键词： Neural networks

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Edge-guided image estimation for array Gm-APD Lidar in smoky environment using multi-scale depth images 6

Edge-guided image estimation for array Gm-APD Lidar in smoky...

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6th Optics Young Scientist Summit, OYSS 2023

作者： Zhang, Yinbo Li, Sining Sun, Jianfeng Jiang, Peng Zhang, Hailong Liu, Zhihui Zhu, Yuebing National Key Laboratory of Science and Technology on Tunable Laser Institute of Opto-Electronic Harbin Institute of Technology Heilongjiang Harbin150001 China Zhengzhou Research Institute of Harbin Institute of Technology Henan Zhengzhou450000 China Science and Technology on Complex System Control Intelligent Agent Cooperation Laboratory Beijing100074 China Sichuan Jiuzhou Electrical Group Company Limited Sichuan Mianyang621000 China

ISBN: (纸本)9781510672642

Limited statistical frame number and strong backscatter interference from smoke result in a photon-starved regime, severely limiting the depth imaging capability of array Gm-APD lidar in smoky environment. Here, we propose a depth image estimation algorithm that can significantly improve the integrity of targets in dense smoke environments when signal photons are starved. At the signal level, the algorithm improves the accuracy of extracting signal photons by constructing multi-scale superpixels. At the image level, using edge information of depth images at different scales to guide and fill the original scale depth image achieves efficient noise reduction and improves target integrity. It has been successfully demonstrated under different attenuation lengths and statistical frame numbers. Compared with other state-of-the-art methods, the proposed algorithm has maximum target recovery and structural similarity, especially for the attenuation length (AL) is 3.6 and statistical frame number is 1500 (imaging time is 75ms). This study is of great significance for the fast depth imaging of dynamic targets by array Gm-APD lidar in dense smoke environments. © COPYRIGHT SPIE. Downloading of the abstract is permitted for personal use only.

关键词： Optical radar

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Portrait image segmentation based on improved grabcut algorithm 6th

Portrait image segmentation based on improved grabcut algori...

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6th International Conference on Swarm Intelligence, ICSI 2015 held in conjunction with the 2nd BRICS Congress on Computational Intelligence, CCI 2015

作者： Li, Shuai Zheng, Xiaohui Chen, Xianjun Zhan, Yongsong Key Laboratory of Cloud Computing and Complex System Guilin University of Electronic Technology Guilin Guangxi541004 China Guangxi Experiment Center of Information Science Guilin University of Electronic Technology Guilin Guangxi541004 China Key Laboratory of Intelligent Processing of Computer Image and Graphics Guilin University of Electronic Technology Guilin Guangxi541004 China Guangxi Key Laboratory of Trusted Software Guilin University of Electronic Technology Guilin Guangxi541004 China Information Engineering School Haikou College of Economics Haikou Hainan571127

ISBN: (纸本)9783319204680

Traditional computer portrait caricature system mainly take the method that exaggerate and deform real images directly, that lead the facial image background also been deformed when exaggerate facial image. If in pretreatment stage, we segmented the characters and background of the input image, and then do the subsequent processing, the problem may be solved. But for better portrait caricature effects, we need an excellent segmentation algorithm. So, we propose an improved Grabcut image segmentation algorithm and use it to extract the prospect character image for exaggeration and deformation. In practical application, we separate deform and exaggerate the foreground characters image with TPS method, then fuse it with the original or new background picture, get the final image. Application proves, the method solves the background deformation problem well, and improves the quality and rate of image segmentation, caricature synthesis effect reality and natural. © Springer International Publishing Switzerland 2015.

关键词： Image segmentation

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Design and implementation of multiple volume servers block level storage system based on load-balanced strategy

International Journal of Database Theory and Application

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International Journal of Database Theory and Application 2014年第4期7卷 59-78页

作者： Wan, Jian Chen, Xun You, Xindong School of Computer Science and Technology Hangzhou Dianzi University Hangzhou China Key Laboratory of Complex System Modeling and Simulation Ministry of Education China

Block level storage system has been widely used as it can provide users raw block device. On the basis of Orthrus system, this paper designs and implements a multiple volume servers block level storage system based on load-balanced strategy-Orthrus Plus. This system uses the dynamic load-balanced strategy based on genetic algorithm strategy to load balance the volume servers clusters and proposes an iSCSI pause and resume method to solve the breakpoint retransmission problem during load-balancing. At last, we design a hierarchical management mechanism based on volume life cycle at storage. Experiments show that the load balancing capability in Orthrus Plus is more accurate and efficient under the situation of larger amount of data, and the hierarchical storage strategy also increases the I/O throughout capacity. © 2013 SERSC.

关键词： Genetic algorithms

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A Task Scheduling Algorithm based on Task Group for Parallel Computing

A Task Scheduling Algorithm based on Task Group for Parallel...

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2015 International Conference on Software, Multimedia and Communication Engineering(SMCE 2015)

作者： Lei WANG Hua-bing WANG Ming-yan CHEN Wei ZHANG State Key Laboratory of Complex Electromagnetic Environment Effects on Electronics and Information System University of Electronic Science and Technology of China

Taking the least task executing cost as objective constraint, a task scheduling algorithm based on task group(TG-Hungary) for parallel computing is presented. In order to satisfy the input condition of Hungary, it adopts matrix partition and virtual phalanx construction to convert input matrix from unbalanced to balanced problem. Experimental results demonstrate that it has better performances than the traditional methods such as Max-Min and Min-Min.

关键词： Task allocation Efficiency matrix Virtual phalanx Load balancing Hungary algorithm

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complex Value Image Group Sparse Coding Denoising Algorithm Based on K-means Clustering Method

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Ruan Jian Xue Bao/Journal of Software 2019年 30卷 17-24页

作者： Liu, Bo-Yu Wu, Ling-Da Hao, Hong-Xing Science and Technology on Complex Electronic System Simulation Laboratory Space Engineering University Beijing101416 China

Sparse coding has been widely used in complex value image demising. In recent years, the proposed block sparse coding has more advantages in noise filtering and noise reduction because it can make full use of the similarity of patches in the same block. In this paper, a K-means clustering method based sparse demising algorithm for complex image grouping is studied. By improving the clustering algorithm, the grouping effectiveness of K-means algorithm for sparse block coding algorithm is verified. The online complex dictionary training algorithm is used to acquire the coded dictionary quickly, and the sparse coding of block image is realized by using the grouping orthogonal matching pursuit algorithm. By inducing the similarity of the coding in each block, the coding of noise in the block is effectively suppressed and the noise reduction of the complex value image is improved. In order to verify the effectiveness of the proposed algorithm, the demising of simulated and real interferometric synthetic aperture radar images is quantitatively analyzed, which proves that the proposed algorithm has a certain improvement in peak signal-to-noise ratio (PSNR) compared with the previous block sparse coding algorithm. Finally, the real interferometric synthetic aperture radar image is demised, which further verifies the de-noising ability of the proposed algorithm for real noise. © Copyright 2019, Institute of Software, the Chinese Academy of sciences. All rights reserved.

关键词： Image denoising

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Design of High-Gain Cavity-Backed Planar Spiral Antenna Based on Arc-Shaped Metasurface

Design of High-Gain Cavity-Backed Planar Spiral Antenna Base...

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International Conference on Microwave and Millimeter Wave technology Proceedings

作者： Jian-yi Chu Lin Peng Jing Ma Bin Shi Yan-ru Hua Zhi-peng Li Xing Jiang Si-min Li Guangxi Key Laboratory of Wireless Wideband Communication and Signal Processing Guilin University of Electronic Technology Guilin Guangxi China Science and Technology on special system simulation laboratory Beijing Simulation Center Beijing China

A high-gain cavity-backed planar spiral antenna based on arc-shaped metasurface (ASM) is proposed and designed. The unidirectional beam of the Archimedean planar spiral antenna (ASA) is achieved by loading the λ/4-distance metal reflector back cavity. A metasurface consisted of arc-shaped unit cells is located at 28mm above the spiral. The simulated results indicate that the impedance bandwidth of the proposed antenna is 4.53-8.29GHz and the axial ratio bandwidth of 3dB is 5.33-8.29GHz. The gain of the cavity-backed planar spiral antenna is increased by dBi in the frequency band 4.5-6.25GHz due to the proposed ASM, and the proposed antenna presents a peak gain of 12.67 dBi at 5.5GHz.

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Design of Dynamically Tunable Broadband Polarization Converter in Terahertz Frequency Based on Graphene Strips

Design of Dynamically Tunable Broadband Polarization Convert...

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International Conference on Microwave and Millimeter Wave technology Proceedings

作者： Tian-Cheng Zheng Lin Peng Xiao Liu Jing Ma Bin Shi Zhi-Hua Zhao Guangxi Key Laboratory of Wireless Wideband Communication and Signal Processing Guilin University of Electronic Technology Guilin Guangxi China Science and Technology on special system simulation laboratory Beijing Simulation Center Beijing China

A dynamically tunable polarization converter has been proposed in this paper, which has a multi-layer structure consisting of an orthogonal cross metallic, graphene strips, spacer substrate and a gold back ground layer. In this paper, the proposed polarization converter can transform the linear polarization incident waves into its cross polarization in reflection mode in terahertz (THz) frequency within an ultra-wideband, and the polarization conversion ratio (PCR) of the proposed structure has over 97% from 4.1 THz to 7.1 THz. Furthermore, by adjusting the chemical potential (or Fermi energy) of the graphene strips, the operating frequency band can be changed dynamically.

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基于晶体塑性的辐照金属材料局部化颈缩和吕德斯带的模拟研究

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Acta Mechanica Sinica 2023年第4期39卷 132-146页

作者：付家琪刘文斌隋昊男程杨洋段慧玲 State Key Laboratory for Turbulence and Complex System Department of Mechanics and Engineering ScienceThe Beijing Innovation Center for Engineering Science and Advanced TechnologyCollege of EngineeringPeking UniversityBeijing100871China Key Laboratory of High Energy Density Physics Simulation Center for Applied Physics and Technologyand Inertial Fusion Sciences and ApplicationsCollaborative Innovation Center of Ministry of EducationPeking UniversityBeijing100871China

金属材料中,颈缩失稳通常由表面缺陷或材料不均匀性等潜在扰动引起并随着微结构的演化进一步发展.本文将构型扰动法与考虑辐照效应的晶体塑性本构关系相结合,模拟了辐照前后局部化颈缩和吕德斯带等现象.通过考虑模拟局部化变形中扰动的... 详细信息

金属材料中,颈缩失稳通常由表面缺陷或材料不均匀性等潜在扰动引起并随着微结构的演化进一步发展.本文将构型扰动法与考虑辐照效应的晶体塑性本构关系相结合,模拟了辐照前后局部化颈缩和吕德斯带等现象.通过考虑模拟局部化变形中扰动的必要性,发现了外在的几何缺陷和内禀的微结构演化在颈缩过程中的竞争关系.此外,以纯金属铜和奥氏体不锈钢为例研究了辐照硬化效应对颈缩失稳的影响.结果表明,流动应力的增加和功硬化能力的降低是均匀延伸率下降的原因,辐照效应导致的织构软化作用可以忽略.为了解释辐照后低碳钢下屈服点和吕德斯应变同时增加的现象,一种位错脱钉扎和位错与辐照缺陷的交互作用相耦合的塑性变形机制被提出并结合修正的流动方程,很好地模拟出包含屈服下降、应力平台、应变扩展和应变硬化等特征的吕德斯带现象.其中,位错与辐照缺陷的相互作用也可以解释辐照后纯金属材料中发现的扩散颈缩现象.我们的模拟结果既阐明了几何缺陷在颈缩失稳中的重要作用,也为辐照金属中常见的宏观塑性失稳现象提供了清晰的物理图像.

关键词：吕德斯带金属材料奥氏体不锈钢晶体塑性下屈服点流动应力几何缺陷均匀延伸率

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