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Comparison of availability and reliability among different combined-GNSS/RNSS precise point positioning

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High Technology Letters 2020年第3期26卷 235-242页

作者： Chen Jian yue dongjie Zhu Shaolin Liu Zhiqiang Dai Jianbiao School of Earth Science and Engineering Hohai UniversityNanjing 211100P.R.China

With emergence of the BeiDou Navigation Satellite System(BDS), the Galileo Satellite Navigation System(Galileo), the Quasi-Zenith Satellite System(QZSS)and the restoration of the Global Navigation Satellite System(GLONASS), the single Global Positioning System(GPS) has been gradually expanded into multiple global and regional navigation satellite systems(multi-GNSS/RNSS). In view of differences in these 5 systems, a consolidated multi-GNSS/RNSS precise point positioning(PPP) observation model is deduced in this contribution. In addition, the performance evaluation of PPP for multi-GNSS/RNSS is conducted using a large number of the multi-GNSS experiment(MGEX) station datasets. Experimental results show that multi-GNSS/RNSS can guarantee plenty of visible satellites effectively. Compared with single-system GPS, PDOP, HDOP, and VDOP values of the multi-GNSS/RNSS are improved by 46.8%, 46.5% and 46.3%, respectively. As for convergence time, the static and kinematic PPP of multi-GNSS/RNSS are superior to that of the single-system GPS, whose reliability, availability, and stability drop sharply with the increasing elevation cutoff. At satellite elevation cutoff of 40 °, the single-system GPS fails to carry out continuous positioning because of the insufficient visible satellites, while the multi-GNSS/RNSS PPP can still get positioning solutions with relatively high accuracy, especially in the horizontal direction.

关键词： precise point positioning(PPP) positioning accuracy convergence rate multiple global and regional navigation satellite systems(multi-GNSS/RNSS) reliability and availability

Experimental research on daily deformation monitoring of steel box girder bridge based on BDS/GPS

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High Technology Letters 2018年第3期24卷 272-278页

作者：陈健 yue dongjie Liu Zhiqiang Zhu Shaolin Chen Hao School of Earth Science and Engineering Hohai University

In order to investigate the feasibility of BDS/GPS in the deformation monitoring of long-span bridges,analysis and research on aspects like number of visible satellites,PDOP value and monitoring precision are carried out. To analyze daily deformation characteristics of steel box girder bridge,observation data for 48 consecutive hours is computed by self-programmed software. Experiment results show that the monitoring-points on the bridge demonstrate obvious periodicity and recoverability in vertical and horizontal directions,meanwhile,changes in the elevation direction are relatively stable. The deformation-monitoring results of BDS/GPS combination system and GPS single system show good consistency. However,in a complex environment of the bridge,especially under the condition that satellite signals are severely affected,the advantages of BDS/GPS combination over GPS single system are more obvious.

关键词： dynamic deformation monitoring BDS/GPS baseline solution daily repeatability long-span bridge

Suppression of Plasma Bubbles over South America under Weak Geomagnetic Perturbations

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Journal of Geodesy and Geoinformation Science 2023年第4期6卷 48-69页

作者： Xunzhe YIN dongjie yue Changzhi ZHAI Yutian CHEN Xiaoyun CHENG School of Earth Sciences and Engineering Hohai UniversityNanjing 210098China

During a long-term Equatorial Plasma Bubbles(EPBs)occurrence between October 2020 and March 2021,a significant EPB suppression event was identified on November 22 and the observations from multi-instrument have been utilized to investigate this ***-scale Observations of the Limb and Disk(GOLD)satellite observed prominent EPBs between 23:40 UT and 23:55 UT during the long-term occurrence ***,no dark stripes representing EPBs were observed on November 22,and the Equatorial Ionization Anomaly(EIA)structure remained *** Total Electron Content(TEC)maps show that these EPBs appeared in the region between 35°W and 65°W longitudes and the magnitudes of the TEC loss in EPBs regions were about 20 *** for 22 November,the S4 index was consistently greater than 0.6 throughout November,indicating significant ionospheric *** Rate Of TEC Index(ROTI)maps revealed that the spatial extent and intensity of EPBs increased after their suppression,and the EPBs were locally *** swarm electron density measurements indicated that the variation amplitudes of EPBs at 510 km altitude were approximately 3 to 5 times larger than that at 460 km *** impact region of EPBs at 510 km was between 15°S and 20°N latitudes,while at 460 km,it was between 0°and 17°N *** the period of EPB suppression,the average h’f at three ionosonde stations decreased by about 50 km,and the vertical drift velocity(V z)approached~0 m/s while it was more than 20 m/s during the long-term occurrence.

关键词： plasma bubble ionospheric scintillation weak geomagnetic perturbations

Analysis of Anomalous Enhancement in TEC and Electron Density in the China Region Prior to the 17 March 2015 Geomagnetic Storm Based on Ground and Space Observations

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Journal of Geodesy and Geoinformation Science 2023年第2期6卷 40-50页

作者： Xiaoyun CHENG dongjie yue Changzhi ZHAI Yutian CHEN Xunzhe YIN School of Earth Sciences and Engineering Hohai UniversityNanjing 211100China

Total Electron Content(TEC)and electron density enhancement were observed on the day before 17 March 2015 great storm in the China *** from ground-and space-based instruments are used to investigate the temporal and spatial evolution of the pre-storm *** enhancement was observed from 24°N to 30°N after 10:00 UT at 105°E,110°E and 115°E longitudes on March *** maximum magnitude of TEC enhancement was more than 10 TECU and the maximal relative TEC enhancement exceeded 30%.Compared with geomagnetic quiet days,the electron density of Equatorial Ionization Anomaly(EIA)northern peak from Swarm A/C satellites on March 16 was larger and at higher ***2 enhanced during 11:30—21:00 UT at Shaoyang Station and increased by 200%at~16:00 ***,TEC and electron density enhancement were not accompanied by a significant change of *** research has excluded some potential mechanisms as the main driving factors for storm-time density enhancements by establishing observational *** this paper,we observed pre-storm enhancement in electron density at different altitudes and Equatorial Electrojet(EEJ)strength results derived from ground magnetometers observations suggest an enhanced eastward electric field from the E region probably played a significant role in this event.

关键词： Equatorial Ionization Anomaly(EIA) electron density geomagnetic storm Total Electron Content(TEC) zonal electric field

Analysis of ionospheric VTEC disturbances before and after the Yutian Ms7.3 earthquake in the Xinjiang Uygur Autonomous Region

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Geodesy and Geodynamics 2014年第3期5卷 8-15页

作者： Wang Xinzhi Jia Junhui yue dongjie Ke Fuyang School of Remote Sensing Nanjing University of Information Science and Technology School of Earth Sciences and Engineering Hohai University

An earthquake with a magnitude of Ms7.3 hit Yutian in the Xinjiang Uygur Autonomous Region on February 14, 2014. This research investigates the interference phenomena in solar activities and geomagnetics, and adopts the quartile method to analyze the Global Ionosphere Map （GIM） Vertical Total Electron Content （VTEC） data provided by the Center for Orbit Determination in Europe （CODE）, as well as the difference between GIM VTEC and International Reference Ionosphere （IRI） VTEC data. The ionospheric VTEC disturbances at the earthquake epicenter are examined before and after the event. At UTC 8：00 on February 2, a strong VTEC disturbance emerged in the sky near the epicenter. A strong VTEC disturbance also emerged in the sky of the southern Hemisphere area, which is symmetric with the areas north of the equator. The methods used in analysis of the difference between GIM VTEC and IRI VTEC information can effectively fill the gaps in analysis that uses only the GIM VTEC data.

关键词： GIM IRI VTEC earthquake ionospheric disturbance

全站仪竖直高程传递技术及其在苏通大桥测控中的应用

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土木工程学报 2007年第5期40卷 100-104页

作者：周建林岳东杰苏通大桥建设指挥部江苏南通226100 河海大学江苏南京210098

高程基准传递是高大建筑物施工测控中重要项目之一,不同的工程因用途不同对高程控制提出不同的精度要求。针对苏通大桥高索塔施工中高程测控的要求,分析水准测量、钢尺高程传递、三角高程测量等常用高程传递技术的适用范围与缺点,它们... 详细信息

高程基准传递是高大建筑物施工测控中重要项目之一,不同的工程因用途不同对高程控制提出不同的精度要求。针对苏通大桥高索塔施工中高程测控的要求,分析水准测量、钢尺高程传递、三角高程测量等常用高程传递技术的适用范围与缺点,它们均不适用于大高差的高精度传递。为此,提出全站仪竖直高程传递技术。详细论述其基本原理,对误差来源、大小进行分析,对所达到的精度进行评估,并研制传递高程的实用装置,经现场试验对比分析,验证该技术方法的可行性与有效性。理论分析与试验验证显示该技术方法对于数百米的高程传递,可以达到国家二等水准精度水平,完全满足建筑物高程测控的需要。最后将该技术成功应用在苏通大桥300m高索塔的高程测控中。

关键词：高程传递全站仪误差分析索塔施工苏通大桥

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基于二进制特征描述符的点云数据配准

激光与光电子学进展 2022年第10期59卷 323-330页

作者：蔡炜岳东杰陈强河海大学地球科学与工程学院江苏南京211100 上海市测绘院三分院上海200063

传统点云数据特征描述符存在表达能力不足、计算效率低和鲁棒性不强等问题,针对二进制形状上下文(BSC)特征描述符不能有效检测到曲率分布较大的区域以及局部坐标系存在二义性的问题,提出了一种基于二进制特征描述符的点云数据配准算法... 详细信息

传统点云数据特征描述符存在表达能力不足、计算效率低和鲁棒性不强等问题,针对二进制形状上下文(BSC)特征描述符不能有效检测到曲率分布较大的区域以及局部坐标系存在二义性的问题,提出了一种基于二进制特征描述符的点云数据配准算法。首先,采用内在形状签名关键点检测法和三维曲面片估计方法改进语义问题。然后,利用汉明距离与改进的几何一致性方法进行特征匹配。最后,用随机抽样一致性算法剔除误匹配。实验结果表明,相比快速点特征直方图、融合点签名的直方图和BSC算法,本算法与迭代最近邻点算法的结合能在大幅度提升配准效率的同时减小配准误差。

关键词：机器视觉二进制形状上下文算法汉明距离点云配准特征匹配迭代最近邻点算法

基于迪杰斯特拉算法的哨兵卫星TOPS模式时序影像精配准

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武汉大学学报（信息科学版） 2020年第6期45卷 904-913页

作者：马张烽岳东杰蒋弥刘恋河海大学地球科学与工程学院江苏南京211100 水文水资源与水利工程科学国家重点实验室江苏南京210098 中国地震局地质研究所北京100029

目前,哨兵卫星被广泛应用于监测地表形变,然而其默认成像模式TOPS(terrain observation with progressive scanning)受粗配准的精度限制,方位向的频谱混叠会导致重叠观测区域出现相位跳变,需要通过精配准进行纠正。多数开源软件都采用... 详细信息

目前,哨兵卫星被广泛应用于监测地表形变,然而其默认成像模式TOPS(terrain observation with progressive scanning)受粗配准的精度限制,方位向的频谱混叠会导致重叠观测区域出现相位跳变,需要通过精配准进行纠正。多数开源软件都采用几何配准和增强谱分集结合的方式对哨兵影像进行精配准。增强谱分集的精度通常受到时间去相干、几何去相干和方位向形变等诸多因素的影响,但其直接影响因素是相干性,研究了增强谱分集的精度与相干性的关系。同时,为了提高时序影像的配准精度,提出在精确估计相干性的基础上提取高相干点用于增强谱分集,并应用迪杰斯特拉最短路径算法生成最优配准像对,完成时序像对的精配准。利用传统的单主影像增强谱分集和目前精度最高的序贯网络增强谱分集(network-based enhanced spectral diversity,NESD)对所提出的方法进行了精度验证。实验证明,所提方法能够达到对哨兵影像进行有效精配准的目的,并且弥补了NESD方法的不足。

关键词：哨兵卫星影像精配准增强谱分集迪杰斯特拉算法 TOPS模式

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变形监测网二级优化设计研究

水力发电学报 1999年第2期18卷 38-44页

作者：岳东杰岳建平华锡生河海大学土木学院

介绍了一种基于Ｔａｙｌｏｒ级数展开的变形监测网二级优化设计的方法，通过理论推导，建立了以准则矩阵为目标，以设计变量的改正数为优化变量的二级优化设计的优化模型；由实例计算分析，说明了该方法的可行性与实用性。

关键词：目标函数二级优化设计变形监测网水工建筑物