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基于负载均衡的导航时分网络建链优化技术研究

第十一届中国卫星导航年会

作者： weisong jia Qiuli Chen Ying Wu Haihong Wang Beijing Institute of Spacecraft System Engineering

Beidou-3 global navigation satellite system(GNSS) has the capability of autonomous navigation. Without the support of the ground system for a long time, it uses the pre-recorded ground auxiliary data,

关键词： Long-term Reliable Design Verification Autonomous Navigation

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航天器工程 2019年第5期28卷 39-45页

作者：贾卫松王琦李露铭岳佳北京空间飞行器总体设计部北京100094 北京跟踪与通信技术研究所北京100094 太原卫星发射中心技术部太原030027

导航卫星可基于相控阵星间链路构成覆盖全球的时分捷变网络,文章针对卫星之间建链拓扑的优化问题进行研究。首先,建立导航卫星星座动态时分建链的拓扑模型,确定了在特定路由策略下,信息路径及网络节点负荷由网络拓扑唯一确定的原则,并... 详细信息

导航卫星可基于相控阵星间链路构成覆盖全球的时分捷变网络,文章针对卫星之间建链拓扑的优化问题进行研究。首先,建立导航卫星星座动态时分建链的拓扑模型,确定了在特定路由策略下,信息路径及网络节点负荷由网络拓扑唯一确定的原则,并分析了导航卫星网络业务流量不对称的特征。然后,基于导航星座模型提出基于目标评价函数进行负载均衡的网络拓扑优化方法,形成建链优化方法的计算步骤。最后,以网络时延和接入能力为指标验证时分网络建链规划方法对负载进行均衡的性能。仿真结果证明了基于负载均衡的时分网络建链优化方法的可行性,对全球卫星导航系统的星间链路管理与运行具有参考价值。

关键词：负载均衡时分网络建链优化接入能力

北斗导航试验卫星综合电子软件研制管理经验与启示

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航天器工程 2016年第4期25卷 108-112页

作者：常克武贾卫松中国卫星导航系统管理办公室北京100054 北京空间飞行器总体设计部北京100094

从软件管理、研制流程、沟通机制、开发模式、配置管理、产品质量6个方面总结了北斗全球卫星导航系统试验卫星综合电子软件研制工作管理实践的主要措施,通过研制成果验证了管理实践措施的有效性,并概括了对北斗全球卫星导航系统组网建... 详细信息

从软件管理、研制流程、沟通机制、开发模式、配置管理、产品质量6个方面总结了北斗全球卫星导航系统试验卫星综合电子软件研制工作管理实践的主要措施,通过研制成果验证了管理实践措施的有效性,并概括了对北斗全球卫星导航系统组网建设及其他后续卫星的软件研制的启示。

关键词：北斗全球卫星导航系统试验卫星综合电子软件管理启示

AFDX端系统设计中的发送调度方法研究与实现

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计算机测量与控制 2010年第11期18卷 2612-2615页

作者：贾卫松翟正军牛仕奇西北工业大学计算机学院陕西西安710072 西北工业大学航海学院陕西西安710072

通过对AFDX协议的研究及对当前端系统常用调度方法的分析,提出索引表静态优先级调度方法(AFDX Index Priority Scheduling——AISP);针对FPGA芯片的设计特点,给出AISP方法的逻辑实现;从优先级、流量整形、确定性等方面对该方法进行分析... 详细信息

通过对AFDX协议的研究及对当前端系统常用调度方法的分析,提出索引表静态优先级调度方法(AFDX Index Priority Scheduling——AISP);针对FPGA芯片的设计特点,给出AISP方法的逻辑实现;从优先级、流量整形、确定性等方面对该方法进行分析和评价,并利用Matlab工具对虚拟链路最大延迟和平均延迟进行仿真;仿真结果证明,AISP调度方法具有较好的实时性,并且能够满足不同紧急程度的网络数据传输的需求。

关键词：优先级调度最大延迟仿真确定性网络传输

北斗全球系统自主导航地面模拟测试系统设计与实现

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航天器工程 2017年第3期26卷 105-111页

作者：贾卫松王海红燕洪成曾连连北京空间飞行器总体设计部北京100094

针对北斗高精度自主导航性能指标的测试验证,设计了支持北斗全球系统星座的自主导航地面模拟测试系统。利用标准航天器链路通信终端接入星载自主导航计算机,实现以远程仿真测试服务器为核心的模拟测试系统架构,从通信机制、时间同步策... 详细信息

针对北斗高精度自主导航性能指标的测试验证,设计了支持北斗全球系统星座的自主导航地面模拟测试系统。利用标准航天器链路通信终端接入星载自主导航计算机,实现以远程仿真测试服务器为核心的模拟测试系统架构,从通信机制、时间同步策略、结果评估方法等方面阐述系统设计原理。工程实践结果表明:文章设计的自主导航地面模拟测试系统,支持在模拟建链场景及误差源的条件下对卫星自主导航进行"跑合"验证,可应用于北斗全球组网卫星设计、测试及在轨运行阶段。其设计方法对其它卫星自主智能任务的测试系统构建亦具有借鉴意义。

关键词：北斗全球系统自主导航地面模拟测试系统

Applications and Prospects for Autonomous Navigation Technology in a Satellite Navigation System

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Applications and Prospects for Autonomous Navigation Technol...

Understanding the local structure and thermophysical behavior of Mg-La liquid alloys via machine learning potential

第十三届中国卫星导航年会

作者： Wei ZHOU Hongliang CAI Haihong WANG Qiuli CHEN Xia LIN Jinglei GUO Xiaojiie LI Chengpan TANG Ruiqiang SHAO Junyang PAN weisong jia Ziqiang LI Beijing Institute of Tracking and Telecommunications Technology Institute of Telecommunication and Navigation Satellites CAST Innovation Academy for Microsatellites of Chinese Academy of Science 32021 Troops Shanghai Astronomical Observatory of Chinese Academy of Science Institute of Space System Engineering 100094 CAST Wuhan University

Autonomous constellation navigation is an important means for improving the continuous delivery of services by satellite navigation systems when experiencing conditions such as major disasters and failure of ground operation control *** is also a useful supplement to the normal operation and control mode,which can reduce dependence on the ground facilities while lowering operating *** article introduces a method for evaluating experiments on the autonomous constellation navigation of satellite navigation *** experiments were based on 12 days of BDS-3 satellite observation *** evaluation results show that for the 12 days of autonomous constellation navigation,the user range error of the satellite orbit was 2.5 m,the accuracy of clock error was 3 ns,and the timekeeping accuracy was approximately 1373 *** pseudorange observation data of 7 domestic stations and 10 global stations of the International GNSS Monitoring and Assessment System（iGMAS） was used to evaluate the positioning *** results show a single-frequency horizontal positioning accuracy of 7.4 m,an altitude positioning accuracy of 9.6 m,a dualfrequency horizontal positioning accuracy of 7.1 m,and an elevation positioning accuracy of 8.9 *** on the results of the experiment,this paper analyses the time-space reference drift problem that affects the accuracy of autonomous navinavigation space signals and proposes an optimized solution.

关键词： satellite navigation system autonomous navigation technology overall rotation constellation timekeeping satellite orbit satellite clock error

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International Journal of Minerals,Metallurgy and Materials 2025年第2期32卷 439-449页

作者： jia Zhao Taixi Feng Guimin Lu National Engineering Research Center for Integrated Utilization of Salt Lake Resource East China University of Science and TechnologyShanghai 200237China Joint International Laboratory for Potassium and Lithium Strategic Resources East China University of Science and TechnologyShanghai 200237China

The local structure and thermophysical behavior of Mg-La liquid alloys were in-depth understood using deep potential molecular dynamic(DPMD) simulation driven via machine learning to promote the development of Mg-La alloys. The robustness of the trained deep potential(DP) model was thoroughly evaluated through several aspects, including root-mean-square errors(RMSEs), energy and force data, and structural information comparison results;the results indicate the carefully trained DP model is reliable. The component and temperature dependence of the local structure in the Mg-La liquid alloy was analyzed. The effect of Mg content in the system on the first coordination shell of the atomic pairs is the same as that of temperature. The pre-peak demonstrated in the structure factor indicates the presence of a medium-range ordered structure in the Mg-La liquid alloy, which is particularly pronounced in the 80at% Mg system and disappears at elevated temperatures. The density, self-diffusion coefficient, and shear viscosity for the Mg-La liquid alloy were predicted via DPMD simulation, the evolution patterns with Mg content and temperature were subsequently discussed, and a database was established accordingly. Finally, the mixing enthalpy and elemental activity of the Mg-La liquid alloy at 1200 K were reliably evaluated,which provides new guidance for related studies.

关键词： magnesium-lanthanum liquid alloys local structure macroscopic properties thermodynamic behavior deep potential mo-lecular dynamic simulation

High-dense nanocrystalline W-based alloy prepared by hot isostatic pressing with uniform microstructure, ultrahigh hardness and good thermal stability

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Tungsten 2025年第1期7卷 120-136页

作者： Zao-Ming Wu Lin He Lin-Sen Ye Xiao-Feng Yang jia-jia Zhang Hong-Bo Lei Institute of Materials China Academy of Engineering Physics

High-density uniform microstructure nanocrystalline W-10wt.% Cr-5wt.% Y（W-10Cr-5Y） alloy with an average grain size of 85 nm and a relative density of 99.8% was successfully prepared.W-Cr-Y alloys with different amounts of second-phase particles were prepared by high-energy ball milling and hot isostatic pressing *** effects of composition design,ball milling parameters,and sintering parameters on the microstructure of W-Cr-Y alloys were studied.A feasible technology for controlling the synthesis of high-density nanocrystalline W-based alloys has been *** microstructure analysis of nanocrystalline W-10Cr-5Y alloy shows that there are two types of doping in the second phase:intergranular doping and intragranular *** "uniform distribution YOx-rich particles" effectively suppresses the grain growth of W and leads to the formation of nanocrystalline W-10Cr-5Y alloy.W-10Cr-5Y has an ultra-high hardness,with a Vickers hardness of 1312±12 kgf·***-temperature annealing treatment shows that W-10Cr-5Y has good thermal stability at 1000 and1100℃,as demonstrated by the comparison of Vickers hardness and grain size between annealed and unannealed alloys.

关键词： Hot isostatic pressing Microstructure Nanocrystalline tungsten Thermal stability Vickers hardness

Thickness and sp3 bond modulation of（Ti/tetrahedral amorphous carbon）_n multilayer coatings

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Tungsten 2025年第1期7卷 152-160页

作者： Zhi-Jun Xie jia-Lin Li Ling Gong Xiang-Li Zhong Hong-jia Song Jin-Bin Wang National-Provincial Laboratory of Special Function Thin Film Materials School of Materials Science and Engineering Xiangtan University

The durability of wear-resistant tetrahedral amorphous carbon（ta-C） coatings is intimately linked to their thickness and the concentration of *** enhance the lifespan of the coatings,we have prepared a multilayer coating consisting of alternating layers of Ti and ta-C,denoted as（Ti/ta-C）_n,using arc ion plating.A multi-layer structure in conjunction with stage cooling is employed to enhance the thickness and promote *** results indicate that the ID/IGvalue,representing the ratio of the intensity of the D peak to that of the G peak in Raman spectroscopy,decreases from 0.85 when no stage cooling is applied to 0.35 when stage cooling is employed,suggesting an enhancement in the fraction of sp3bonds within the *** obtained（Ti/ta-C）_n multilayer coating without peeling off has a maximum thickness of 1.14 μm,which is almost double that of the ta-C coating single layer *** the same time,the coating has a low coefficient of friction,down to 0.069,and maintains excellent friction properties with a wear rate of 3.4×10-6mm3·N-1·*** results conclusively show that the preparation technology can enhance both thickness and sp3bonding in ta-C coatings,significantly expanding their utility across tools,molds,and precision engineering components.

关键词： Arc ion plating Multilayer structure sp3 bond Ta-C coating Wear resistance