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Combined adjustment project of national astronomical geodetic networks and 2000' national GPS control network

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Progress in Natural Science:Materials International 2005年第5期15卷 435-441页

作者： YANG Yuanxi1*, ZHA Ming2, SONG Lijie3. WEI Ziqing1, WANG Zhouping2, OUYANG Guichong2, XU Bilin2, WU Xiaoping3.and WANG Junqin4(1. Xi'an Research institute of surveying and mapping, Xi'an 710054, China 2. Xi'an Informational and Technical Center of surveying and mapping, Xi'an 710054, China 3. zhengzhou institute of surveying and mapping, zhengzhou 450052, China 4. The First surveying Team of Tianjin, Tianjin 3.0140, China) Xian Research institute of surveying and mapping Xi''an 710054 China Xi''an Informational and Technical Center of surveying and mapping Xi''an 710054 China zhengzhou institute of surveying and{3. Zhengzhou 450052 China

The combined adjustment project of the nationwide astronomical geodetic networks and 2000' national GPS control network involve 48519 terrestrial observational stations and 2666 GPS observational stations. In the terrestrial network, 25107 stations are height fixed and 23.12 stations are in three dimensions. 440793.terrestrial observations and 183.68 unknowns are involved in the adjustment. The three-dimensional observational models for the adjustment have been established. The crustal deformation influences and corrections are researched. Fast methods of solving partitioned adjustment for super large-scale geodetic network have been studied. The standard deviations of three-dimensional coordinates for all stations are evaluated. As a result of the combined adjustment, a unified national geodetic network with nearly 50000 stations is established, the high accurate three-dimensional geocentric coordinates are obtained. The standard deviation for geoid is averagely 0.2 m, for vertical deflection is about 1.5″, for the horizontal position is about 0.12 m, for the geodetic height is about 0.14 m, and for the three-dimensional position is averagely 0.3.m.

关键词： astronomical geodetic network GPS network combined adjustment datum geocentric coordinates.

A new learning statistic for adaptive filter based on predicted residuals

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Progress in Natural Science:Materials International 2006年第8期16卷 833-837页

作者： YANG Yuanxi and GAO Weiguang (Xi'an Research institute of surveying and mapping, Xi'an710054, China institute of surveying and mapping, University of Information Engineering, zhengzhou 450052, China) [a]Xi' an Research institute of surveying and mapping Xi' an China [b]institute of surveying mapping University of Information Engineering Zhengzhou China

A key problem for an adaptive filter is to establish a suitable adaptive factor for balancing the contributions of the measurements and the predicted state information from some kinematic models. The reasonable adaptive factor needs a reliable learning statistics to judge the state kinematic model errors. After analyzing the existing two kinds of learning statistics based on the state discrepancy and variance component ratio, a new learning statistic based on predicted residuals is set up, which is different from the exiting learning statistics. The new learning statistic does not need to estimate the kinemetic state parameters before the filtering process, Of course, it does not need necessary measurements to estimate state parameters for all observation epochs. The new learning statistic can be applied together with the learning factor constructed by the state discrepancy. The advantages and shortcomings of the new learning factor are analyzed, and an example is given.

关键词： adaptive factor adaptive filter kinematic model predicted residual.

The gravitational gradient tensor’s invariants and the related boundary conditions

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Science China Earth Sciences 2010年第5期53卷 781-790页

作者： YU JinHai1,2,3.& ZHAO DongMing4 1 College of Earth Science, Graduate University of Chinese Academy of Sciences, Beijing 100049, China 2 institute of Geodesy and Geophysics, Chinese Academy of Sciences, Wuhan 43.077, China 3.State Key Laboratory of Astronautic Dynamics, Xi’an 710043. China 4 zhengzhou institute of surveying and mapping, zhengzhou 450052, China 1. College of Earth Science Graduate University of Chinese Academy of Sciences Beijing 100049 China2. Institute of Geodesy and Geophysics Chinese Academy of Sciences Wuhan 430077 China3. State Key Laboratory of Astronautic Dynamics Xi’an 710043 China4. Zhengzhou Institute of Surveying and Mapping Zhengzhou 450052 China

Here we report new approaches of recovering the Earth gravitational field from GOCE (Gravity field and steady-state Ocean Circulation Explorer) gradiometric data with the help of the gradient tensor’s invariants. Our results only depend on GOCE satellite’s position and gradiometry, in other words, they are completely independent of the satellite attitude. First, starting from the invariants, linearization models are established, which can be referred as the general boundary conditions on the satellite’s orbit. Then, the spherical approximation expressions for the models are derived, and the corresponding solving methods for them are discussed. Furthermore, considering effects of J2-term, the spherical approximation models are improved so that the accuracies of the boundary conditions can be theoretically raised to O ( J 2/2 T), which is approximately equivalent to O(T2). Finally, some arithmetic examples are constructed from EGM96 model based on the derived theories, and the computational results illustrate that the spherical models have accuracies of 10-7 and the order recovering the gravitational field can reach up to 200, and the models with regard to effect of J2-term have accuracies of 10-8 and the order can reach up to 280.

关键词： the Earth’s gravitational field gravitational gravidiometry tensor’s invariant

A　SUPERLINEARLY　CONVERGENT　GENERALIZED　GRADIENT　PROJECTION　ALGORITHMFOR　LINEARLY　CONSTRAINED　PROBLEMS

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Systems Science and Mathematical Sciences 1995年第4期8卷 299-310页

作者： HE Guoping GAO Ziyou(institute of Applied Mathematics,Academia Sinica,Beijing 100080,China)ZHU Jianqing (zhengzhou institute of{3. and mapping,zhengzhou 450052,China) 中科院应用数学所北京解放军郑州测绘学院河南郑州 450052

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关键词： Generalized gradient projection method linearly constrained problem superlinear convergence pivoting operation.

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铁路客车技术整备所线路配置规模研究

中国铁路 2024年第5期 118-123页

作者：张雄张正舟中铁二院工程集团有限责任公司四川成都610031 中国铁路经济规划研究院有限公司北京100038

合理确定铁路客车技术整备所的整备线和车底停留线配置规模,对于节约用地和降低工程投资非常重要。TB 10029—2009《铁路客车车辆设备设计规范》第4.3.2条规定,按入所列车数量确定线路数量,并给出相应的计算表。结合规范修订工作,采用... 详细信息

合理确定铁路客车技术整备所的整备线和车底停留线配置规模,对于节约用地和降低工程投资非常重要。TB 10029—2009《铁路客车车辆设备设计规范》第4.3.2条规定,按入所列车数量确定线路数量,并给出相应的计算表。结合规范修订工作,采用线性回归法和概率分析法对线路配置规模进行研究,并对该条规定在当前的适用性进行验证。研究结论如下:(1)按照列车运行图确定客车车底出入客车技术整备所的时间,分析其最大车底停留数量,从而确定整备线和车底停留线数量之和的方法,是确定客车技术整备所线路数量的准确方法。(2)按照入所车底数量和配置系数确定线路数量方法可行,全路客车技术整备所计算平均数量与运行图分析法计算结果的误差为0.3.~7.5%,符合性较好。(3.将3.计算方法应用到具体铁路客车整备所时,全路各所的均方根误差为25%~27%,该误差受运行图编制主客观因素影响,由各客运站列车终到/始发时间分布规律差异造成,可通过运行图调整来适应。

关键词：铁路客车整备所整备线停留线线路配置规模

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In-situ Formation of Spinel Fibers in MgO-C Refractory Matrixes

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Journal of Wuhan University of Technology(Materials Science) 2009年第6期24卷 896-902页

作者：谢朝晖 High Temperature Ceramics institute Zhengzhou University

In-situ magnesia-rich spinel fiber was formed resulting from the addition of ferrocene into MgO-C refractory matrixes. The formation of in-situ spinel fiber was detected to start at 13.0 ℃. The amount, diameter and length of the fibers increased with rising temperature. Ferrocene may have catalytic effects on the growth of the fibers in two aspects. First, the reaction between MgO and C and the decomposition of Al4C3.may be catalyzed at high temperature. Suitable concentration gaseous phase is then created for vapor-vapor reaction which could result in the in-situ formation of fibers. Second, Fe nanoparticle produced from ferrocene can act as catalytic droplets and catalyze the growth of the fibers. The fibers are formed via the vapor-liquid-solid and vapor-solid mechanisms. In terms of chemical thermodynamics, the partial pressure of CO and Mg（g） are found to play an important role in the in-situ fibers formation. Different concentration of vapors affects the size, amount and composition of the fibers at different temperatures. The mechanical properties of MgO-C brick was found to be improved by ferrocene addition.

关键词： spinel fiber in-situ formation ferrocene MgO-C brick refractory.

基于邻域向量主成分分析图像增强的旁瓣弱光信号检测方法

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中国激光 2024年第6期51卷 109-123页

作者：王拯洲王力段亚轩李刚魏际同中国科学院西安光学精密机械研究所先进光学仪器研究室陕西西安710119

针对基于旁瓣光束衍射反演的强激光远场焦斑测量无法提取旁瓣图像更外围最小可测信号的问题,笔者提出了基于邻域向量主成分分析(NVPCA)图像增强的旁瓣弱光信号区域波峰参数检测方法。采取的主要优化措施为:首先,将旁瓣图像中的每个像素... 详细信息

针对基于旁瓣光束衍射反演的强激光远场焦斑测量无法提取旁瓣图像更外围最小可测信号的问题,笔者提出了基于邻域向量主成分分析(NVPCA)图像增强的旁瓣弱光信号区域波峰参数检测方法。采取的主要优化措施为:首先,将旁瓣图像中的每个像素和它的8邻域像素看作一个列向量,构建一个9维数据立方体,选择主成分分析变换后的第1维数据为NVPCA图像;其次,通过角度变换转化检测对象,检测所有方向上一维旁瓣曲线的各个波峰参数,获得旁瓣弱光信号区域能量的量化分布;然后,搜索每个旁瓣波峰在所有方向上的极大值位置点,连接对应位置点生成每个旁瓣波峰的极大值圆环,计算各极大值圆环的灰度均值;最后,选择大于局域对比度方法(LCM)目标分离阈值且最小的极大值圆环的灰度均值作为整个旁瓣光束的最小可测信号。实验结果表明,采用基于NVPCA图像增强的旁瓣弱光信号检测方法能够从旁瓣图像的第5波峰环分离和提取最小可测信号,动态范围比值提升至原来的1.528倍,各旁瓣波峰参数满足精度要求,为未来大型激光装置强激光远场的精确测量奠定了基础。

关键词：远场测量邻域向量主成分分析旁瓣光束衍射反演角度变换旁瓣波峰参数检测

National 2000' GPS control network of China

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Progress in Natural Science:Materials International 2007年第8期17卷 983-987页

作者： Yang Yuanxi~(1**) Tang Yingzhe~1 Chen Chuanlu~2 Wang Min~3.Zhang Peng~4 Wang Xiaorui~2 Song Lijie~5 Zhang Zusheng~6 (1.Xi'an Research institute of surveying and mapping,Xi'an 710054,China 2.Geodetic Data Processing Center,Xi'an 710054,China 3.Center of Earthquake Analysis and Prediction,China Seismological Bureau,Beijing 10003.,China 4.National Geomatics Center of China,Beijing 100044,China 5.institute of surveying and mapping,zhengzhou University of Information Engineering,zhengzhou 450052,China 6.First Crustal Deformation Monitoring Center,China Seismological Bureau,Tianjin 3.0180,China) [a]Xi' an Research institute of surveying and mapping Xi' an China [b]Geodetic Data Processing Center Xi'an China [c]Center of Earthquake Analysis and Prediction China Seismological Bureau Beijing China [d]National Geomatics Center of Chinna Beijing China [e]institute of surveying and mapping Zhengzhou University of Information Engineering Zhengzhou China [f]First Crustal Deformation Monitoring Center China Seimological Bureau Tianjin China

An accurately unified national GPS network with more than 2500 stations,named"National 2000' GPS Control Net- work",signed the epoch 2000.0,has been established by integrating the existing six nationwide GPS networks of China set up by differ- ent departments with different *** paper presents the characteristics of the existing GPS networks,summarizes the strategies in the integrated adjustment of the GPS network,including functional model,stochastic model as well as the adjustment principle modifi- *** modifying the adjustment strategies according to the characteristics of the existing GPS networks and under the support of the IGS stations,the accuracy of the integrated national GPS network is greatly *** datum differences among the sub networks disappear,the systematic error influences are weakened,and the effects of the outliers on the estimated coordinates and their variances are *** is shown that the average standard deviation for the horizontal component is smaller than 1.0 cm,the vertical component is smaller than 2.0 cm,and the three-dimensional (3.D) position of geocenter coordinates is smaller than 3.0 *** exterior checking ac- curacy for the 3.D position is averagely better than 1.0 cm.

关键词： GPS control network adjustment systematic errors robust estimation variance component estimation coordinate system

Proton induced X-ray emission (PIXE) analysis of sources of porcelain body of Ru Guan and Jun Guan porcelains

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Science China(Physics,Mechanics & Astronomy) 2006年第4期49卷 411-420页

作者： LI Guoxia1, ZHAO Weijuan1, LI Rongwu2, SUN Hongwei1, GUO Min1, WANG Yanfang1, LIU Hui1, ZHAO Qingyun3. SUN Xinmin3. ZHAO Wenjun3.& CHENG Huansheng4 1. Faculty of Physical Engineering, zhengzhou University, zhengzhou 450052, China 2. Department of Physics, Beijing Normal University, Beijing 100875, China 3. institute of Cultural Relic and Archaeology of Henan Province, zhengzhou 450000, China 4. institute of Modern Physics, Fudan University, Shanghai 20043., China Faculty of Physical Engineering Zhengzhou University Zhengzhou 450052 China Department of Physics Beijing Normal University Beijing 100875 China institute of Cultural Relic Archaeology of Henan Province Zhengzhou 450000 China institute of Modern Physics Fudan University Shanghai 200433 China

3. samples of Ru Guan porcelain body and 50 samples of Jun Guan porcelain body (both kinds being in different body colors) were selected with the purpose of finding out the source of raw materials and their classification relationship so as to search for ways of non-destructive discrimination. Proton induced X-ray emission (PIXE) has been applied to these samples to determine their chemical elements. The data of seven major chemical elements collected from these samples were further studied through fuzzy cluster analysis. Results indicate that the origin of raw materials of Jun Guan porcelain body samples is comparatively more concentrated in certain places, while that of Ru Guan porcelain body samples is scattered about. The places of origin of raw materials of the majority of Ru Guan and Jun Guan porcelain body samples have something in common, but some differences still exist. It might be an important way for non-destructive discrimination among Ru Guan and Jun Guan porcelains by combining PIXE with fuzzy cluster analysis.

关键词： Ru Guan and Jun Guan porcelain, source of porcelain body, PIXE, fuzzy cluster analysis, non-destructive discrimination.