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

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 430077, china 3 State Key Laboratory of Astronautic Dynamics, Xi’an 710043, china 4 zhengzhou institute of surveying and mapping, zhengzhou 450052, china College of Earth Science Graduate University of Chinese Academy of Sciences Beijing China institute of Geodesy and Geophysics Chinese Academy of Sciences Wuhan China State Key Laboratory of Astronautic Dynamics Xi’an China zhengzhou institute of surveying and mapping Zhengzhou 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

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Design and verification of an FPGA programmable logic element based on Sense-Switch pFLASH

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Frontiers of Information Technology & Electronic Engineering 2024年第4期25卷 485-499页

作者： zhengzhou CAO Guozhu LIU Yanfei ZHANG Yueer SHAN Yuting XU No.58 Research institute China Electronics Technology Group CorporationWuxi 214035China

This paper proposes a kind of programmable logic element(PLE)based on Sense-Switch pFLASH *** programming Sense-Switch pFLASH,all three-bit look-up table(LUT3)functions,partial four-bit look-up table(LUT4)functions,latch functions,and d flip flop(DFF)with enable and reset functions can be *** PLE uses a choice of operational logic(COOL)approach for the operation of logic functions,it allows any logic circuit to be implemented at any ratio of combinatorial logic to *** intrinsic property makes it close to the basic application specific integrated circuit(ASIC)cell in terms of fine granularity,thus allowing ASIC-like cell-based mappers to apply all their optimization *** measuring Sense-Switch pFLASH and PLE circuits,the results show that the“on”state driving current of the Sense-Switch pFLASH is about 245.52μA,and that the“off”state leakage current is about 0.1 *** programmable function of PLE works *** delay of the typical combinatorial logic operation AND3 is 0.69 ns,and the delay of the sequential logic operation DFF is 0.65 ns,both of which meet the requirements of the design technical index.

关键词： Field programmable gate array(FPGA) Programmable logic element(PLE) Boolean logic operation Look-up table Sense-Switch pFLASH Threshold voltage

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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) Xi'an Research institute of surveying and mapping Xi'an 710054 China institute of surveying and mapping University of Information Engineering Zhengzhou 450052 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.

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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 300140, china) Xi'an Res. Inst. of surveying and mapping Xi'an 710054 China Xi'an Info. and Technical Ctr. of surveying and mapping Xi'an 710054 China zhengzhou Inst. of surveying and mapping Zhengzhou 450052 China First surveying Team of Tianjin Tianjin 300140 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 23412 stations are in three dimensions. 440793 terrestrial observations and 183668 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.

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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 surveying 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

Ａ　ＳＵＰＥＲＬＩＮＥＡＲＬＹＣＯＮＶＥＲＧＥＮＴＧＥＮＥＲＡＬＩＺＥＤＧＲＡＤＩＥＮＴＰＲＯＪＥＣＴＩＯＮＡＬＧＯＲＩＴＨＭＦＯＲＬＩＮＥＡＲＬＹＣＯＮＳＴＲＡＩＮＥＤ　ＰＲＯＢＬＥＭＳＮｅｗａｄｄｒｅｓｓ：Ｓｈａ... 详细信息

Ａ　ＳＵＰＥＲＬＩＮＥＡＲＬＹＣＯＮＶＥＲＧＥＮＴＧＥＮＥＲＡＬＩＺＥＤＧＲＡＤＩＥＮＴＰＲＯＪＥＣＴＩＯＮＡＬＧＯＲＩＴＨＭＦＯＲＬＩＮＥＡＲＬＹＣＯＮＳＴＲＡＩＮＥＤ　ＰＲＯＢＬＥＭＳＮｅｗａｄｄｒｅｓｓ：ＳｈａｎｄｏｎｇＭｉｎｉｎｇｉｎｓｔｉｔｕｔｅ，Ｓｈａｎｄｏｎｇ，Ｔａｉａｎ２７１０１９．＊Ｎｅｗａｄｄｒｅｓｓ：ＮｏｒｔｈｅｒｎＪｉａｏｔｏｎｇＵｎｉｖｅｒｓｉｔｙｌＢｅ１Ｊｉｎｇ１０００４０．ａｐｉｖｏｔｉｎｇｏｐｅｒａｔｉｏｎｉｎｏｒｄｅｒｔｏｄｅｔｅｒｍｉｎｅａｎｅ－ａｃｔｉｖｅｓｅｔｏｆｃｏｎｓｔｒａｉｎｔｓ．Ｓｅｃｏｎｄｌｙ，ｏｎｅｍｕｓｔｃｏｍｐｕｔｅａｎｅｗｐｒｏｊｅｃｔｉｏｎｍａｔｒｉｘａｔｅａｃｈｓｔｅｐ．Ｔｈｅｓｅａｒｅａｌｌｔｉｍｅ－－ｃｏｎｓｕｍｉｎｇａｎｄｏｆｔｅｎｍａｋｅｔｈｅａｌｇｏｒｉｔｈｍｔｏｂｅｕｎｓｔａｂｌｅ．ＩｎｔｈｉｓｐａｐｅｒｓｂｙｕｓｉｎｇｔｈｅｃｏｎｃｅｐｔｏｆｇｅｎｅｒａｌｉｚｅｄｐｒｏｊｅｃｔｉｏｎｍａｔｒｉＸｗｈｉｃｈｗａｓｐｒｏｐｏｓｅｄｉｎ［８］，ｗｅｉｍｐｒｏｖｅＷｕ＇ｓａｌｇｏｒｉｔｈｍａｎｄｐｒｅｓｅｎｔａｎｅｗａｌｇｏｒｉｔｈｍ．Ｕｎ?

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

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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种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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EFFECT OF Ti ON MICROSTRUCTURE OF RAPIDLY SOLIDIFIED Al-Si ALLOYS

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Acta Metallurgica Sinica(English Letters) 1992年第4期5卷 292-296页

作者： SHAO Guosheng SHEN Ningfu zhengzhou institute of Technology,zhengzhou,china zhengzhou Inst of Technology Zhengzhou China

An addition of Ti as alloying element to Al-Si binary alloy will reduce the undercooling-abili- ty on rapid solidification of the melt-spun *** microstructure will be encoarsened even at initiation of its solidificati... 详细信息

关键词： rapid solidification Ti Al-Si alloy structure

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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 1300 ℃. 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.

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TRACKING OBSERVATION ON SUBSURFACE CRACK IN BEARING STEEL GCr15 UNDER ROLLING CONTACT

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Acta Metallurgica Sinica(English Letters) 1992年第2期5卷 128-132页

作者： CHEN Longqing zhengzhou institute of Technology,zhengzhou,china CHEN Qing Luoyang institute of Technology,Luoyang,china zhengzhou Inst of Technology Zhengzhou China

Based on the sequent tracking observation on spalling of steel GCr15 under rolling contact fa- tigue,an expression for estimating the propagation of subsurface cracks was *** rol- ling contact fatigue life was found to be markedly related to the subsurface crack propagation angle.A new explanation of reason why the rolling contact fatigue life can be prolonged by residual compressive stress and retained austenite was advanced.

关键词： contact fatigue fatigue life crack propagating angle residual stress retained austenite

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2022年苹果产业发展概况(二)——苹果期货、标准与品牌建设

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中国果菜 2024年第4期44卷 1-4,8页

作者： china Apple Industry Association National Apple Industry Technology System Jinan Fruit Research institute,All china Federation of Supply & Marketing Cooperatives zhengzhou Commodity Exchange 中国苹果产业协会国家苹果产业技术体系中华全国供销合作总社济南果品研究所郑州商品交易所

1苹果期货交易情况1.1苹果期货交割机构根据郑州商品交易所官网消息,苹果期货现有交割仓库1家(陕西),交割厂库19家(陕西9家、山东6家、甘肃3家、河南1家),车船板交割服务机构18家(陕西8家、山东7家、甘肃3家)。苹果交割仓库、厂库及车... 详细信息

1苹果期货交易情况1.1苹果期货交割机构根据郑州商品交易所官网消息,苹果期货现有交割仓库1家(陕西),交割厂库19家(陕西9家、山东6家、甘肃3家、河南1家),车船板交割服务机构18家(陕西8家、山东7家、甘肃3家)。苹果交割仓库、厂库及车船板交割服务机构分布在陕西、山东、甘肃及河南等省。1.2苹果期现货运行情况2022年,苹果期货价格整体呈现先扬后抑的走势,主要分为三个阶段。

关键词：期货交易期货价格苹果交割

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