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For LEO Satellite Networks: Intelligent Interference Sensing and Signal Reconstruction Based on Blind Separation Technology

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China Communications 2024年第2期21卷 85-95页

作者： Chengjie Li lidong zhu Zhen Zhang The Key Laboratory for Computer Systems of State Ethnic Affairs Commission School of Computer Science and Technology(Southwest Minzu University)Chengdu 610000China National Key Laboratory of Science and Technology on Communications(University of Electronic Science and Technology of China) Chengdu 610000China College of Computer Science(Sichuan University) Chengdu 610000China

In LEO satellite communication networks,the number of satellites has increased sharply, the relative velocity of satellites is very fast, then electronic signal aliasing occurs from time to time. Those aliasing signals make the receiving ability of the signal receiver worse, the signal processing ability weaker,and the anti-interference ability of the communication system lower. Aiming at the above problems, to save communication resources and improve communication efficiency, and considering the irregularity of interference signals, the underdetermined blind separation technology can effectively deal with the problem of interference sensing and signal reconstruction in this scenario. In order to improve the stability of source signal separation and the security of information transmission, a greedy optimization algorithm can be executed. At the same time, to improve network information transmission efficiency and prevent algorithms from getting trapped in local optima, delete low-energy points during each iteration process. Ultimately, simulation experiments validate that the algorithm presented in this paper enhances both the transmission efficiency of the network transmission system and the security of the communication system, achieving the process of interference sensing and signal reconstruction in the LEO satellite communication system.

关键词： blind source separation greedy optimization algorithm interference sensing LEO satellite communication networks signal reconstruction

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A Support Data-Based Core-Set Selection Method for Signal Recognition

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China Communications 2024年第4期21卷 151-162页

作者： Yang Ying zhu lidong Cao Changjie National Key Laboratory of Wireless Communications(University of Electronic Science and Technology of China) Chengdu 611731China College of Computer Science and Cyber Security(Chengdu University of Technology) Chengdu 610059China College of Mathmatics and Physics(Chengdu University of Technology) Chengdu 610059China

In recent years,deep learning-based signal recognition technology has gained attention and emerged as an important approach for safeguarding the electromagnetic ***,training deep learning-based classifiers on large signal datasets with redundant samples requires significant memory and high *** paper proposes a support databased core-set selection method(SD)for signal recognition,aiming to screen a representative subset that approximates the large signal ***,this subset can be identified by employing the labeled information during the early stages of model training,as some training samples are labeled as supporting data *** support data is crucial for model training and can be found using a border sample *** results demonstrate that the SD method minimizes the impact on model recognition performance while reducing the dataset size,and outperforms five other state-of-the-art core-set selection methods when the fraction of training sample kept is less than or equal to 0.3 on the RML2016.04C dataset or 0.5 on the RML22 *** SD method is particularly helpful for signal recognition tasks with limited memory and computing resources.

关键词： core-set selection deep learning model training signal recognition support data

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Energy-Efficient Traffic Offloading for RSMA-Based Hybrid Satellite Terrestrial Networks with Deep Reinforcement Learning

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China Communications 2024年第2期21卷 49-58页

作者： Qingmiao Zhang lidong zhu Yanyan Chen Shan Jiang National Key Laboratory of Science and Technology on Communications University of Electronic Science and Technology of ChinaChengdu 611731China The Higher Educational Key Laboratory for Flexible Manufacturing Equipment Integration of Fujian Province Xiamen Institute of TechnologyXiamen 361021China China Mobile(Jiangxi)Communications Group Co. LtdYichun 336000China

As the demands of massive connections and vast coverage rapidly grow in the next wireless communication networks, rate splitting multiple access(RSMA) is considered to be the new promising access scheme since it can provide higher efficiency with limited spectrum resources. In this paper, combining spectrum splitting with rate splitting, we propose to allocate resources with traffic offloading in hybrid satellite terrestrial networks. A novel deep reinforcement learning method is adopted to solve this challenging non-convex problem. However, the neverending learning process could prohibit its practical implementation. Therefore, we introduce the switch mechanism to avoid unnecessary learning. Additionally, the QoS constraint in the scheme can rule out unsuccessful transmission. The simulation results validates the energy efficiency performance and the convergence speed of the proposed algorithm.

关键词： deep reinforcement learning energy efficiency hybrid satellite terrestrial networks rate splitting multiple access traffic offloading

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Material Composition of the Newly Discovered Zongzhuo Formation Sedimentary Mélange in Dingri Area, Southern Tibet, and its Constraints on the Basin Controlling Dingri-Gamba Fault

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ACTA GEOLOGICA SINICA-ENGLISH EDITION 2024年第5期98卷 1171-1186页

作者： Yan, Songtao Ding, Ailing Dai, Xuejian Li, Hu Liu, Tao zhu, lidong Wu, Qingsong China Geol Survey Civil Mil Integrat Ctr Chengdu 610036 Peoples R China Chengdu Univ Technol Coll Earth Sci Chengdu 610059 Peoples R China Chengdu Univ Informat Technol Sch Software Engn Chengdu 610225 Peoples R China Chengdu Univ Technol Inst Sedimentary Geol Chengdu 610059 Peoples R China

The study of sedimentary m & eacute;langes holds pivotal importance in understanding orogenic processes and unveiling geodynamic mechanisms. In this study, we present findings on zircon U-Pb isotopes and whole-rock elemental data concerning the recently uncovered Zongzhuo Formation sedimentary m & eacute;langes within the Dingri area. Field observations reveal the predominant composition of the Zongzhuo Formation, characterized by a matrix of sandstone-mudstone mixed with sand-conglomerates within native blocks exhibiting soft sediment deformation. Moreover, exotic blocks originating from littoral-neritic seas display evidence of landslide deformation. Our study identifies the depositional environment of the Zongzhuo Formation in Dingri as a slope turbidite fan, with its provenance traced back to the passive continental margin. Notably, this contrasts with the Zongzhuo Formation found in the Jiangzi-Langkazi area. Based on existing data, we conclude that the Zongzhuo Formation in the Dingri area was influenced by the Dingri-Gamba fault and emerged within a fault basin of the passive continental margin due to Neo-Tethys oceanic subduction during the Late Cretaceous period. Its provenance can be attributed to the littoral-neritic sea of the northern Tethys Himalaya region. This study holds significant implications for understanding the tectonic evolution of Tethys Himalaya and for reevaluating the activity of the Dingri-Gamba fault, as it controls the active deposition of the Zongzhuo Formation.

关键词： sedimentary m & eacute lange provenance analysis Zongzhuo Formation Dingri-Gamba fault Tethys Himalaya ZIRCON U-PB MELANGE-FORMING PROCESSES GANGDESE BATHOLITH TETHYAN HIMALAYA VOLCANIC-ROCKS LHASA TERRANE SUTURE ZONE ARC LEUKOGRANITES EVOLUTION

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Material Composition of the Newly Discovered Zongzhuo Formation Sedimentary Mélange in the Dingri Area, Southern Tibet, and its Constraints on the Basin Controlling Dingri–Gamba Fault

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Acta Geologica Sinica(English Edition) 2024年第5期 1171-1186页

作者： YAN Songtao DING Ailing DAI Xuejian LI Hu LIU Tao zhu lidong WU Qingsong Civil-Military Integration Center of China Geological Survey China Geological Survey School of Software Engineering Chengdu University of Information Technology College of Earth Science Chengdu University of Technology Institute of Sedimentary Geology Chengdu University of Technology

The study of sedimentary mélanges holds pivotal importance in understanding orogenic processes and unveiling geodynamic mechanisms. In this study, we present findings on zircon U-Pb isotopes and whole-rock elemental data concerning the recently uncovered Zongzhuo Formation sedimentary mélanges within the Dingri area. Field observations reveal the predominant composition of the Zongzhuo Formation, characterized by a matrix of sandstone-mudstone mixed with sand-conglomerates within native blocks exhibiting soft sediment deformation. Moreover, exotic blocks originating from littoral–neritic seas display evidence of landslide deformation. Our study identifies the depositional environment of the Zongzhuo Formation in Dingri as a slope turbidite fan, with its provenance traced back to the passive continental margin. Notably, this contrasts with the Zongzhuo Formation found in the Jiangzi–Langkazi area. Based on existing data, we conclude that the Zongzhuo Formation in the Dingri area was influenced by the Dingri–Gamba fault and emerged within a fault basin of the passive continental margin due to Neo-Tethys oceanic subduction during the Late Cretaceous period. Its provenance can be attributed to the littoral–neritic sea of the northern Tethys Himalaya region. This study holds significant implications for understanding the tectonic evolution of Tethys Himalaya and for reevaluating the activity of the Dingri–Gamba fault, as it controls the active deposition of the Zongzhuo Formation.

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基于SNP模式的高中地理论证教学研究——以“冰川地貌”为例

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地理教学 2024年第2期 12-14页

作者：任晴雯朱丽东浙江师范大学地理与环境科学学院浙江金华321004

SNP模式是一种将科学建模与论证融合的教学方式,能加强学生对地理事象的本质理解,发展学生的地理思维。本文在构建SNP模式与高中地理教学联系的基础上,以“冰川地貌”为例,阐述SNP模式在地理教学中的实践路径,并从情境选择、核心问题设... 详细信息

SNP模式是一种将科学建模与论证融合的教学方式,能加强学生对地理事象的本质理解,发展学生的地理思维。本文在构建SNP模式与高中地理教学联系的基础上,以“冰川地貌”为例,阐述SNP模式在地理教学中的实践路径,并从情境选择、核心问题设计、建模与论证、反思与评价四个方面对SNP模式在高中地理教学中的应用提出建议。

关键词： SNP模式地理论证教学冰川地貌

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中国式现代化融入高中地理主题式教学的实践探索——以“象山的海洋发展历程”为例

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地理教学 2024年第5期 40-43页

作者：祝清波周翔朱丽东浙江师范大学地理与环境科学学院浙江金华321004

海洋世纪的背景下,海洋发展战略已然成为中国式现代化发展的重要战略。本文从中国式现代化为何融入、融入什么、如何融入三方面,探讨其融入地理教学的适切性。本文基于主题式教学设计,依托象山的海洋发展历程的真实案例,融入中国式现代... 详细信息

海洋世纪的背景下,海洋发展战略已然成为中国式现代化发展的重要战略。本文从中国式现代化为何融入、融入什么、如何融入三方面,探讨其融入地理教学的适切性。本文基于主题式教学设计,依托象山的海洋发展历程的真实案例,融入中国式现代化思想,深化学生的海洋素养,并采用多元化的评价体系,检验学生的学习过程和素养目标的落实程度。

关键词：中国式现代化主题式教学高中地理海洋素养

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PCD刀具超声振动辅助铣削TC4钛合金仿真与试验

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制造技术与机床 2024年第9期 58-64页

作者：朱立东刘晓峰吉林铁道职业技术学院智能制造学院吉林吉林132000 中国人民解放军空军航空大学吉林长春130000

TC4钛合金是典型的难加工材料,为解决其导热性差对铣削加工性能的影响,文章提出超声振动辅助铣削加工工艺,以提高其铣削质量。通过Abaqus建立PCD铣刀及TC4钛合金工件的仿真模型,分析超声振动对PCD铣刀切削刃温度的影响;采用单因素法设... 详细信息

TC4钛合金是典型的难加工材料,为解决其导热性差对铣削加工性能的影响,文章提出超声振动辅助铣削加工工艺,以提高其铣削质量。通过Abaqus建立PCD铣刀及TC4钛合金工件的仿真模型,分析超声振动对PCD铣刀切削刃温度的影响;采用单因素法设计超声振动铣削试验,研究不同超声振幅与刀具前角对PCD铣刀切削刃温度、铣削力及工件表面粗糙度的影响;并将试验结果与仿真结果进行对比,验证仿真模型的可靠性。结果表明,超声辅助铣削可大幅降低切削刃温度和铣削力,还可有效降低工件表面的粗糙度。相较普通铣削,超声铣削的切削刃平均温度由421.5℃下降到241.9℃,降幅为42.6%;铣削力由104.65 N下降到87.05 N,降幅为16.8%;工件表面粗糙度均值由0.316μm下降到0.228μm,降幅为27.8%。超声振幅较铣刀前角对表面粗糙度的影响更明显,且仿真结果和试验结果基本一致,其平均误差为4.6%。

关键词： TC4钛合金超声振动有限元仿真 PCD铣刀铣削加工

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Non-Orthogonal Multi-Carrier Transmission for Internet via Satellite

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China Communications 2017年第3期14卷 31-42页

作者： Yang Yang lidong zhu National Key Laboratory of Science and Technology on Communications University of Electronic Science and Technology of ChinaChengdu 611731 China

As the important complementary to terrestrial mobile communications, Internet via satellite can extend the coverage of communication and improve the continuity of data services. To build a space-terrestrial integrated communication system is the inevitable trend in the future. Taking into account combination of 5th generation(5G) terrestrial mobile communication system and satellite communication system, it is necessary to evaluate the promising 5G air interface waveform which can be adopted by satellite. In this paper, several non-orthogonal multi-carrier transmission schemes are evaluated and generalized frequency division multiplexing(GFDM) is advised as potential scheme of space-terrestrial integrated communication system. After the overview of GFDM, the implementation of GFDM transceiver is discussed respectively in time-domain and in frequency-domain. By deriving and comparing implementation complexity, GFDM modulation in time-domain is more suitable for satellite communication system. Then the properties of demodulation algorithms are specified. Based on designed pilot subcarriers, a new improved receiving algorithm is proposed in the end of the paper. The improved algorithm solves the problem of inter subcarriers interference(ICI) in matched filtering(MF) receiver and improves the re-ceiving symbol error rate(SER) obviously. The simulation and analysis prove that the proposed algorithm is effective.

关键词： Internet via satellite air interface non-orthogonal modulation interference cancellation

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基于Online-GRU信道预测的星上自适应功率控制方法

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太赫兹科学与电子信息学报 2024年第3期22卷 261-268页

作者：施文军朱立东电子科技大学通信抗干扰全国重点实验室四川成都611731

针对传统卫星功率控制方法存在资源浪费、时延长的问题,提出一种基于在线-门控循环单元(Online-GRU)信道预测的星上自适应功率控制方法,通过在线训练更新网络参数来解决离线预测算法存在的累积误差的问题。仿真结果表明,提出的在线训练... 详细信息

针对传统卫星功率控制方法存在资源浪费、时延长的问题,提出一种基于在线-门控循环单元(Online-GRU)信道预测的星上自适应功率控制方法,通过在线训练更新网络参数来解决离线预测算法存在的累积误差的问题。仿真结果表明,提出的在线训练算法比离线算法预测精确度提升了38.30%,相比在线-长短期记忆网络(Online-LSTM)节约了63.21%的训练时间;提出的自适应功率控制方法比固定发射功率的方法节约了55.74%的发射功率;同时,相比基于地面定时反馈信道状态的自适应功率控制方法具备更好的鲁棒性。

关键词：星上自适应功率控制在线训练在线-门控循环单元信道预测

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