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Satellite-Ground Link Planning Method for LEO Satellite Navigation Augmentation Network in the case of Multiple Ground Stations

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Satellite-Ground Link Planning Method for LEO Satellite Navi...

Information Transmission Path Selection of Navigation Satellite Network Based on Directional Crosslink

第十三届中国卫星导航年会

作者： Yanghongyi Kuang xianqing yi Zhenwei Hou Science and Technology on Information Systems Engineering Laboratory National University of Defense Technology National Innovation Institute of Defense Technology Academy of Military Science

Aiming at satellite-ground link planning problem for LEO satellite navigation augmentation network in the case of multiple ground stations, we proposes a planning method based on graph theory. First, according to the boundary assumption and essential analysis of satellite-ground link planning problem for LEO satellite navigation augmentation network in the case of multiple ground stations, we establishes a corresponding mathematical model. Then, based on the need to quickly solve the approximate optimal solution of the above model, a graph theory-based satellite-ground link planning method is proposed, and the performance of the solution result of this method is theoretically proved. Finally, the simulation results verify the effectiveness of the method actually applied to the LEO satellite navigation augmentation network in the case of multiple ground stations.

关键词： multiple ground stations LEO satellite navigation augmentation satellite-ground link planning

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Information Transmission Path Selection of Navigation Satell...

Research on Space-based Measurement and Control Scheme of Launch Vehicle Based on BeiDou Navigation Satellite System

第七届中国卫星导航学术年会

作者： Zhenwei Hou xianqing yi Yue Zhao Yaohong Zhang Science and Technology on Information Systems Engineering Laboratory National University of Defense Technology

Autonomous navigation using an inter-satellite ranging and communication with inter-satellite links（ISL） is the trend of satellite navigation system development. By controlling the direction of phased array antenna flexibly, the directional crosslink can achieve more information from other satellites. However, the efficiency of communication is affected at the same time. In this paper, we analyse the navigation satellite network assembled directional crosslink, and then we propose a solution to describe the progress of information transmission based on building directional graph. Then we present a method of finding Earliest Journey and Shortest Journey. According to simulation result, the method we present is practicable and we also achieve some valuable conclusions.

关键词： Directional crosslink Satellite navigation Path selection Routing algorithm

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Research on Space-based Measurement and Control Scheme of La...

第九届中国卫星导航学术年会

作者： Chong Li xianqing yi Yue Zhao Zhenwei Hou Science and Technology on Information Systems Engineering Laboratory National University of Defense Technology

In order to solve the problem of remote monitoring and control of launch vehicles,this paper proposes that Bei Dou navigation satellite system can achieve the real-time measurement and control of the launch vehicle,based on the analysis of the support of the space-based measurement and control system for the launch vehicle measurement and control *** then proposes space-based measurement and control system *** to the composing and task supporting ability of Bei Dou navigation satellite system,the communication process of Bei Dou navigation satellite system supporting the global launch vehicle space-based measurement and control is analyzed and ***,according to the Bei Dou global navigation satellite system,three kinds of constellation support communication schemes are designed and three networking constellations are proposed to support the space-based measurement and control ***,the feasibility of the communication scheme is verified through simulation experiments,which provides a better solution for the space-based measurement and control system of the launch vehicle.

关键词： BeiDou Navigation Satellite System Launch vehicle Communication scheme Space-based measurement and control

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星间链路方案的设计与评价方法

装备学院学报 2017年第1期28卷 74-80页

作者：赵岳易先清侯振伟国防科技大学信息系统工程重点实验室湖南长沙410073

星间链路技术降低了卫星通信网络对地面站的依赖,使得基于星间链路的卫星通信与组网具有地面网络难以比拟的优势。传统研究集中于星间链路的可行性分析和构建方法,对星间链路方案设计缺乏评价。从实际应用的系统性和构建流程的完整性出... 详细信息

星间链路技术降低了卫星通信网络对地面站的依赖,使得基于星间链路的卫星通信与组网具有地面网络难以比拟的优势。传统研究集中于星间链路的可行性分析和构建方法,对星间链路方案设计缺乏评价。从实际应用的系统性和构建流程的完整性出发,提出一种基于星座特性分析的星间链路方案设计方法,并为方案性能检验和选择提出了基于路由性能的评价方法。最后,通过对实际系统星间链路方案的设计和评价,验证了所提方法能够针对任务需求构建可行方案并通过路由性能比较选出最优方案。

关键词：星间链路拓扑结构方案设计路由性能评价方法

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轮询建链规则下导航卫星信息传输路径选择

装备学院学报 2015年第3期26卷 69-73页

作者：侯振伟易先清钟涛赵岳国防科技大学信息系统与管理学院湖南长沙410072

基于轮询建链的相控阵星间链路方案在星间观测等方面具有优势,同时也对信息传输的路径选择提出了挑战。针对轮询建链规则下网络拓扑频繁时变的问题,对信息传输的路径选择进行了研究。在Walker24/3/2星座基础上假定了一种轮询建链规则,... 详细信息

基于轮询建链的相控阵星间链路方案在星间观测等方面具有优势,同时也对信息传输的路径选择提出了挑战。针对轮询建链规则下网络拓扑频繁时变的问题,对信息传输的路径选择进行了研究。在Walker24/3/2星座基础上假定了一种轮询建链规则,构建了相应的数学模型对信息传输过程进行描述,在假定规则和所提数学模型的基础上,提出了一种星座内信息传输路径选择方法,保证在不影响星间测距的前提下,解决了多个导航信息在任意卫星节点间并发传输时的路径选择计算问题。最后以单个信息和2个信息流的并发传输为例,通过Matlab仿真计算证明了方法的可行性,对全球导航系统星间链路的路由选择具有一定的参考价值。

关键词：卫星导航轮询建链星间链路路径选择

Coagulation indices and fibrinogen degradation products as predictive biomarkers for tumor-node-metastasis staging and metastasis in gastric cancer

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World Journal of Gastrointestinal Oncology 2025年第1期17卷 110-120页

作者： yi-Qing Shen Qiu-Wan Wei yi-Ren Tian Yun-Zhi Ling Min Zhang Clinical Laboratory Civil Aviation Shanghai HospitalGubei Branch of Ruijin Hospital Affiliated to Shanghai Jiao Tong University School of MedicineShanghai 200000China Clinical Laboratory Tongji Hospital of Tongji UniversityShanghai 200000China

BACKGROUND Gastric cancer(GC)is a prevalent malignancy with a substantial health burden and high mortality rate,despite advances in prevention,early detection,and *** with the global average,Asia,notably China,reports disproportionately high GC *** disease often progresses asymptoma-tically in the early stages,leading to delayed diagnosis and compromised ***,it is crucial to identify early diagnostic biomarkers and enhance treatment strategies to improve patient outcomes and reduce *** Retrospectively analyzed the clinical data of 148 patients with GC treated at the Civil Aviation Shanghai Hospital between December 2022 and December *** associations of coagulation indices-partial thromboplastin time(APTT),prothrombin time(PT),thrombin time(TT),fibrinogen,fibrinogen degradation products(FDP),fasting blood glucose,and D-dimer(D-D)with TNM stage and distant metastasis were *** Prolongation of APTT,PT,and TT was significantly correlated with the GC TNM ***,abnormal coagulation system activation was closely related to disease *** FDP and D-D were significantly associated with distant metastasis in GC(P<0.05),suggesting that increased fibrinolytic activity contributes to increased metastatic *** Our Results reveal coagulation indices,FDPs as GC biomarkers,reflecting abnormal coagulation/fibrinolysis,aiding disease progression,metastasis prediction,and helping clinicians assess thrombotic risk for early intervention and personalized treatment plans.

关键词： Coagulation indexes Fibrinogen degradation products Gastric cancer Tumor-node-metastasis staging Distant metastasis

基于星间链路的导航卫星网络自适应路由策略与机制研究方法

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装备学院学报 2014年第1期25卷 50-54页

作者：易先清张耀鸿钟涛侯振伟国防科学技术大学信息系统与管理学院湖南长沙410073

由于北斗全球导航卫星系统(Beidou global navigation satellite system,BGNSS)在全球范围内的建站约束,采用星间链路(inter-satellite links,ISL)传输其全球导航综合信息(global navigation integrated information,GNII)成为必选途径,其核心问题之一是适应BGNSS传输需求的GNII传输路径选择。通过分析BGNSS星间链路建链特征,探索其对GNII传输时路径选择的约束要素与约束关系。分析北斗GNII业务特征,研究满足其传输需求的路径选择约束要素与约束关系。再对这些约束要素与约束关系展开建模分析,探索适应星间链路特点与GNII传输需求的约束要素调整反馈机制,通过仿真验证基于星间链路的GNII传输路径自适应选择策略与机制。

关键词：卫星导航路由策略链路研究方法

雌二醇对EOMA细胞增殖、ERα、ERβ及VEGF表达的影响

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重庆医学 2017年第14期46卷 1878-1880,1884页

作者：宋晓峰王宁李亚莎金先庆王佚李晓庆周德凯重庆医科大学附属儿童医院胃肠外科及新生儿外科/儿童发育疾病研究教育部重点实验室/重庆市儿童发育重大疾病诊治与预防国际科技合作基地/儿科学重庆市重点实验室重庆400014

目的探讨17β-雌二醇(E2)对鼠源性血管瘤血管内皮细胞(EOMA细胞)生长,雌激素α、β受体亚型(ERα、β)及血管内皮生长因子(VEGF)表达的影响。方法用1、10、100nmol/L浓度的E2分别作用于EOMA细胞,同时设对照组(不加E2)。四甲基偶氮唑蓝(M... 详细信息

目的探讨17β-雌二醇(E2)对鼠源性血管瘤血管内皮细胞(EOMA细胞)生长,雌激素α、β受体亚型(ERα、β)及血管内皮生长因子(VEGF)表达的影响。方法用1、10、100nmol/L浓度的E2分别作用于EOMA细胞,同时设对照组(不加E2)。四甲基偶氮唑蓝(MTT)法检测不同时间点其对EOMA细胞生长的影响;Western blot检测EOMA细胞的ERα、β表达强度;酶联免疫吸附试验(ELISA)检测细胞培养上清液中VEGF的分泌水平。结果 1nmol/L E2组在36h时高于对照组(P<0.05);10nmol/L E2组、100nmol/L E2组各个时间点OD值均明显高于对照组(P<0.05),36h时OD值最高(P<0.01)。E2作用下10nmol/L E2组ERα和ERβ水平及100.0nmol/L E2组ERα水平较对照组均明显增高(P<0.05)。24、48h时,各浓度E2组与对照组的VEGF水平比较均差异有统计学意义(P<0.05),48h时100nmol/L E2组和10nmol/L E2组VEGF水平均高于1nmol/L E2组(P<0.05)。结论 E2可促进EOMA细胞增殖,可能主要通过ERα、VEGF表达水平上调来实现。

关键词：雌二醇雌激素受体α 雌激素受体β 内皮,血管血管瘤鼠源性血管内皮瘤内皮细胞血管内皮生长因子

Bowel preparation before colonoscopy: Consequences, mechanisms, and treatment of intestinal dysbiosis

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World Journal of Gastroenterology 2025年第2期31卷 13-26页

作者： Ze-Long Zheng Qing-Fan Zheng Li-Qiang Wang yi Liu Department of Gastroenterology(Endoscopy Center) China-Japan Union Hospital of Jilin UniversityChangchun 130033Jilin ProvinceChina

The term“gut microbiota”primarily refers to the ecological community of various microorganisms in the gut,which constitutes the largest microbial community in the human *** adequate bowel preparation can improve the results of colonoscopy,it may interfere with the gut *** preparation for colonoscopy can lead to transient changes in the gut microbiota,potentially affecting an individual’s health,especially in vulnerable populations,such as patients with inflammatory bowel ***,measures such as oral pro-biotics may ameliorate these adverse *** focused on the bowel prepa-ration-induced changes in the gut microbiota and host health status,hypothesized the factors influencing these changes,and attempted to identify measures that may reduce dysbiosis,thereby providing more information for individualized bowel preparation for colonoscopy in the future.

关键词： Bowel preparation Colonoscopy Microbiota Inflammatory bowel disease Probiotics