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Interpolation Fitting Algorithm in Time-Space Domain of Differential Barometric Altimetry

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Journal of Beijing Institute of Technology 2019年第1期28卷 119-128页

作者： Zhengqun Hu Lirong Zhang guanyi ma Yuanfa Ji National Astronomical Observatories Chinese Academy of Sciences Key Laboratory of Cognitive Radio and Information Processing Ministry of EducationGuilin University of Electronic Technology Guangxi Key Laboratory of Precision Navigation Technology and Application

In order to overcome the limitations of a unitary reference station in mobile communication positioning network differential barometric altimetry(DBA)and broaden the action scope of the reference station and improve positioning accuracy of elevation,an integrated interpolation algorithm model based on generalized extended approximation(GEA)algorithm and Kriging interpolation in time-space domain of reference station is *** the time domain,barometric measured data is considered the maximum value estimated by bilateral extension to avoid wrong direction of estimation,which is approaching true *** the spatial domain,barometric relevance among multiple reference stations is utilized,the weighted coefficients of multiple reference stations is calculated by the integrated algorithm model based on the GEA algorithm and Kriging *** impact of each reference station to the measured station is quantified,so that a virtual reference station is constructed,which can overcome the limitation of barometric correction by a unitary reference *** addition,the measurement error due to irregular change in atmospheric pressure will be eliminated.

关键词： differential barometric altimetry(DBA) multi reference station generalized extended approximation(GEA) Kriging algorithm

Research on positioning enhancement scheme of CAPS via UWB pseudolite

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Science China(Physics,Mechanics & Astronomy) 2012年第4期55卷 733-737页

作者： XIAO Zhu BAI Jing ma guanyi FAN JiangTao YI KeChu College oflnformation Science and Engineering Hunan UniversityChangsha 410082China State Key Laboratory oflntegrated Service Networks Xidian UniversityXi'an 710071China Key Laboratory oflntelligent Perception and Image Understanding of Ministry of Education Xidian UniversityXi'an 710071China National Astronomical Observatories Chinese Academy of SciencesBeijing 100012China

The positioning precision of the transmitting Chinese Area Positioning System(CAPS) is reduced due to the non-ideal distribution of the satellite *** and navigation enhancement methods are able to improve the reliability and accuracy of the positioning system,especially for users in special regions and special *** this paper,a positioning enhanced scheme based on ultra-wide band(UWB) pseudolite is proposed for *** is demonstrated that the link budget of UWB pseudolite satisfies the FCC's emission mask *** localization algorithm of the enhanced CAPS is *** simulations indicate that the positioning precision of the proposed enhanced scheme is improved greatly,and the feasibility of the enhanced scheme is thus proved.

关键词：定位方案 CAPS 超宽带定位精度定位系统卫星星座导航方法辐射屏蔽

A neural network based ionospheric TEC derivation method with only carrier phase observations

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A neural network based ionospheric TEC derivation method wit...

A study of ionospheric height’s effects on the derivation of GPS-TEC

第十一届中国卫星导航年会

作者： Weijun Lu guanyi ma National Astronomical Observatories Chinese Academy of Sciences University of Chinese Academy of Sciences

In derivation of ionospheric total electron content(TEC) with global navigation satellite system(GNSS), because the pseudorange contains large observation noise and the carrier phase includes unknown

关键词： Ionosphere Total electron content Artificial neural network Instrumental bias Root mean square error

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A study of ionospheric height’s effects on the derivation o...

Network analysis of suicide ideation and depression-anxiety symptoms among Chinese adolescents

第五届中国卫星导航学术年会

作者： Xiaolan Wang guanyi ma University of Chinese Academy of Sciences National Astronomical Observatories Chinese Academy of Sciences

Based on a thin layer assumption of the ionosphere and the spherical harmonic model, this paper adopts the algorithm spherical harmonic model to de- rive the total electron content （TEC） for a GPS observational chain with 60 dual frequency receivers in the whole world. The paper examines the performance of the algorithm and investigates the effects the assumed ionospheric height on the derived TEC by applying it to the data selected October 1, 2004. The results show that the data can be well fitted,and there are some effects to GPE-TEC but with- out dependence on the ionospheric model height.

关键词： GPS TEC ionospheric height spherical harmonic model

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General Psychiatry 2024年第2期37卷 216-223页

作者： Shuyin Xu Yumeng Ju Xiyu Wei Wenwen Ou Mohan ma guanyi Lv Xiaotian Zhao Yaqi Qin Yunjing Li Liang Li Mei Huang Siqi Yang Yimei Lu Yafei Chen Junwu Liu Jin Liu Bangshan Liu Yan Zhang Department of Psychiatry National Clinical Research Center for Mental Disordersand National Center for Mental DisordersThe Second Xiangya Hospital of Central South UniversityChangshaHunanChina Mental Health Institute of Central South University China National Technology Institute on Mental DisordersHunan Technology Institute of PsychiatryHunan Key Laboratory of Psychiatry and Mental HealthHunan Medical Center for Mental HealthChangshaHunanChina

Background The co-occurrence of depression and anxiety among adolescents is typically associated with suicide *** The study aimed to investigate the symptom-level relationship between suicide ideation and the comorbidity of depression and *** 1501 adolescents aged 12-19 years were assessed using the Patient Health Questionnaire(PHQ-9)and the Generalized Anxiety Disorder Scale,and 716 adolescents who scored≥5 on both scales were selected as *** analysis was used to identify the network structure of depressive symptoms and anxiety *** were categorised into either the suicide ideation or non-suicide ideation groups based on their scoring on the suicide-related item in PHQ-9.A comparison was made between the depression-anxiety symptom networks of the two ***‘Restlessness’,‘sad mood’and‘trouble relaxing’were the most prominent central symptoms in the depression-anxiety symptom network,and‘restlessness’,‘nervousness’and‘reduced movement’were the bridge symptoms in this network.‘Sad mood’was found to be directly related to‘suicide ideation’with the highest *** network structure was significantly different in properties between the suicide ideation group and the non-suicide ideation group,with‘restlessness’and‘sad mood’exhibiting significantly higher influence in the network of the suicide ideation group than that in the non-suicide ideation *** Restlessness and sad mood could be targeted for the intervention of depression-anxiety symptoms among adolescents with suicide ideation.

关键词： symptoms adolescent assessed

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基于神经网络的准实时单站电离层TEC反演

天文研究与技术 2022年第2期19卷 141-148页

作者：卢伟俊马冠一中国科学院国家天文台北京100101 中国科学院大学北京100049

使用全球导航卫星系统(Global Navigation Satellite System,GNSS)进行电离层总电子含量(Total Electron Content,TEC)反演时,单站相对于多站观测网是一种灵活简便的方法。基于人工神经网络(Artificial Neural Network,ANN)提出了一种准实时单站电离层总电子含量反演的方法。在这种方法中,上一个时段的硬件偏差作为初值并随着观测值调整,同时电离层总电子含量也准实时反演。为了对这种方法进行详细评估,通过位于中国的单站,4天磁静日的总电子含量分别采用本文方法与经典的最小二乘球谐函数法反演,其中硬件偏差和总电子含量的参考值通过附近的多站网得到。在另一个测试中,通过位于欧洲的单站,一次电离层暴事件及前后磁静日的总电子含量也分别通过上述方法反演。在磁静日,估计的硬件偏差整体上相对于最小二乘球谐函数法更接近参考值,反演的总电子密度更接近参考值。电离层暴时,两种方法反演的总电子含量也具有高度一致性,神经网络法估计的硬件偏差与磁静日的硬件偏差更接近。结果表明,提出的神经网络法相比最小二乘球谐函数法具有较高的精度。

关键词：电离层人工神经网络总电子密度硬件偏差电离层暴

A Study of TEC storm on 13 October 2016

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A Study of TEC storm on 13 October 2016

基于双频GPS观测的电离层TEC与硬件延迟反演方法

第九届中国卫星导航学术年会

作者： Qingtao Wan Jinghua Li Xiaolan Wang Jiangtao Fan Jie Zhang guanyi ma National Astronomical Observatories Chinese Academy of Sciences

An ionospheric positive storm on 13 October 2016 was *** longitude effect of ionospheric storm along 40°N latitude region is studied with 23 GPS stations from 0°E to 360°*** electron content(TEC) was calculated with polynomial method,and TEC difference between the storm time and quiet time(ΔTEC) were *** variations of TEC difference were different at different *** was a positive phase storm at the local time day side region,while the variations were not obvious at the night side *** maximum value of ΔTEC was about 25 TECU at 330°E at about 1400 UT on 13 October *** Ionosonde data at EB040(0.5 °E,40°N) and RL052(51.5 °N,359.4 °E) were also used to study the ionospheric *** Δfo F2 of RL052 increased earlier that low latitude ionosonde of *** was a second peak of ΔTEC at the local night time about 2000 LT on 13 October *** latitude effect of ionospheric storm was also studied with 7 GPS stations at 0°E *** was found that the positive storm was obvious at high latitude region,while it was weak at low latitude *** phenomenon may be caused by the fountain *** high latitude to low latitude,ΔTEC gradually began to increase,and ΔTEC at higher latitude reached the maximum value earlier than the low *** show that the positive ionospheric storm may be caused by the equatorward surge.

关键词： GPS station Ionosonde Total electron content equatorward surge

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空间科学学报 2014年第2期34卷 168-179页

作者：王晓岚马冠一中国科学院大学北京100049 中国科学院国家天文台北京100012

利用全球定位系统(Global Positioning System,GPS)的双频观测数据反演得到电离层的总电子含量(Total Electron Content,TEC),使得广域甚至全球范围高时空分辨率的电离层观测研究成为可能,但由于GPS卫星和接收机对信号的硬件延迟可导致... 详细信息

利用全球定位系统(Global Positioning System,GPS)的双频观测数据反演得到电离层的总电子含量(Total Electron Content,TEC),使得广域甚至全球范围高时空分辨率的电离层观测研究成为可能,但由于GPS卫星和接收机对信号的硬件延迟可导致TEC测量系统偏差,因此,需要探索反演TEC并估测GPS卫星与接收机硬件延迟的有效算法.本文根据电离层电波传播理论,阐述了基于双频GPS观测提取电离层TEC的方法,给出TEC与硬件延迟的基本关系.综合研究了TEC与硬件延迟的反演方法,进行分析与归纳分类,在此基础上提出了有待深入研究的问题.

关键词： GPS 电离层 TEC 硬件延迟

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GNSS接收机锁相环最佳环路带宽的选取

电讯技术 2015年第8期55卷 890-894页

作者：张杰马冠一中国科学院国家天文台北京100012 中国科学院大学北京100049

锁相环环路带宽值的选取对于锁相环的跟踪误差性能有重要影响。基于全球卫星导航系统(GNSS)接收机中常用锁相环结构与数学模型,首先介绍了锁相环及其重要组成部分环路滤波器的结构和原理,然后分析了环路带宽的取值对锁相环两个最重要的... 详细信息

锁相环环路带宽值的选取对于锁相环的跟踪误差性能有重要影响。基于全球卫星导航系统(GNSS)接收机中常用锁相环结构与数学模型,首先介绍了锁相环及其重要组成部分环路滤波器的结构和原理,然后分析了环路带宽的取值对锁相环两个最重要的误差源——环路热噪声误差和晶振阿伦偏差的影响,给出了低动态下使锁相环总的跟踪误差最小的最佳环路带宽的理论表达式。对基于由现场可编程门阵列(FPGA)芯片、温补晶振和模/数接口电路构建的实际硬件接收机平台进行了验证,结果表明:当根据最佳环路带宽的理论表达式取环路带宽值时,锁相环的跟踪误差最小。所推得的理论表达式不仅可以应用于GNSS接收机,也适用于一般的载波跟踪环设计。

关键词： GNSS接收机锁相环环路滤波器最优环路带宽