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1.
2.
Janis Britals 《Celestial Mechanics and Dynamical Astronomy》1992,54(4):305-316
It is shown in this paper how to build a canonical transformation of variables, so that the eccentric anomaly becomes the new independent variable. In the case of eccentric elliptical orbits it changes the equations of motion so, that they can be integrated analytically to any order of approximation comparatively easy. 相似文献
3.
Christopher Kotsakis 《Journal of Geodesy》2009,83(1):31-50
All gravity field functionals obtained from an Earth gravitational model (EGM) depend on the underlying terrestrial reference
frame (TRF), with respect to which the EGM’s spherical harmonic coefficients refer to. In order to maintain a coherent framework
for the comparison of current and future EGMs, it is thus important to investigate the consistency of their inherent TRFs,
especially when their use is intended for high precision studies. Following the methodology described in an earlier paper
by Kleusberg (1980), the similarity transformation parameters between the associated reference frames for several EGMs (including
the most recent CHAMP/GRACE models at the time of writing this paper) are estimated in the present study. Specifically, the
differences between the spherical harmonic coefficients for various pairs of EGMs are parameterized through a 3D-similarity
spatial transformation model that relates their underlying TRFs. From the least-squares adjustment of such a parametric model,
the origin, orientation and scale stability between the EGMs’ reference frames can be identified by estimating their corresponding
translation, rotation and scale factor parameters. Various aspects of the estimation procedure and its results are highlighted
in the paper, including data weighting schemes, the sensitivity of the results with respect to the selected harmonic spectral
band, the correlation structure and precision level of the estimated transformation parameters, the effect of the estimated
differences of the EGMs’ reference frames on their height anomaly signal, and the overall feasibility of Kleusberg’s formulae
for the assessment of TRF inconsistencies among global geopotential models. 相似文献
4.
Ning Gaidi 《地球科学与环境学报》1997,(2)
本文介绍了由8031单片机控制的LED发光二极管阵列构成的电子显示屏显示原理、显示屏数据锁存、驱动接口电路、键盘接口电路、字模存放电路及软件框图。 相似文献
5.
Lawrence M. Mayer Peter T. Rahaim William Guerin Stephen A. Macko Les Watling Franz E. Anderson 《Estuarine, Coastal and Shelf Science》1985,20(4):491-503
A variety of measures of organic matter concentration and quality were made on samples collected from the top few mm of intertidal mudflat sediment over the course of a year, in order to assess the relative importance of biological and sedimentological influences on sedimentary organic matter. Winter and summer were times of relatively fine-grained sediment accumulation, caused by biological deposition or stabilization processes and resulting in higher organic matter concentrations. Stable carbon isotope and Br:C ratios indicated a planktonic source of bulk organic matter. Ratios of organic carbon to specific surface area of the sediments were consistent with an organic monolayer coverage of sediment grains. Correction for changing grain size during the year showed no change in the organic concentration per unit surface area, in spite of organic matter inputs by in situ primary production, buildup of heterotroph biomass and mucus coatings, and biodeposition of organic-rich seston. There were also no indications of changes in bulk organic quality, measured as hydrolyzable carbohydrates and amino acids, in response to these biological processes. It is concluded that biological processes on a seasonal time scale affect the bulk organic matter of these sediments via a modulation of grain size rather than creation or decay of organic matter. 相似文献
6.
Numerical methods are usually used for the computation of ephemerides with perturbations for the precise orbital determination of an artificial satellite. But their numerical stability will be encountered in a long arc. In this case the use the improved Encke special perturbation methods has been suggested. The results of this paper show that Encke's method does indeed have a certain effectiveness, but cannot yet completely resolve the numerical stability, and the more efficient method is to use the energy integral or its variational relation to control the growth of the along-track error in general numerical calculations so that the aim of stabilization can be achieved. 相似文献
7.
提要 本文详细讨论了一种三维重力位场快速正反演方法。作者在前人工作的基础上,对算法作了行之有效的改进,通过对反演中的不稳定因素进行各种理论模型试算,得出保证迭代反演稳定收敛的准则,编制出可在微型机IBM—PC上运行的人机对话式自动正反演程序。本文还对各种不均质模型进行了模似计算并将该方法应用于某含油气沉积盆地的双层界面构造研究,揭示出了储油有利地段。 相似文献
8.
9.
激光粒度仪的广泛应用带来了与历史数据的对比问题,因此需要建立激光粒度仪与早期分析结果之间的关系。根据江苏海岸潮滩沉积物样品的激光粒度仪和移液管-筛析法分析,对粒度参数、粒度组分等进行了对比,对两种方法的差异进行了分析。结果表明,对于江苏潮滩沉积物粒度参数中平均粒径的激光粒度仪与移液管-筛析分析结果之间有良好的线性关系;筛分法测得的粗颗粒物质较激光法偏少,而移液管法法测得的细颗粒物质较激光法偏多;将样品分类之后再进行两种方法所获粒度参数的回归分析,相关性得以提高,说明不同粒度组成的沉积物对分析结果的对比有不同的影响。两种方法之间的换算关系不仅与研究区域有关,而且与沉积物本身的粒度组成有关。 相似文献
10.
1.0GPa和常温至1100 ℃条件下角闪石斜长片麻岩的V_p变化:实验测量与理论计算 总被引:3,自引:0,他引:3
在1.0GPa、常温至1100℃条件下测量了角闪石斜长片麻岩的纵波速度(Vp),并统计了不同温度实验产物中各种矿物的体积百分含量。结果显示,1.0GPa下,角闪石斜长片麻岩的Vp首先随温度升高(室温至700℃)缓慢降低约6%,然后(700—850℃)快速降低约6%,再(850~950℃)转而急剧升高15%~25%,最后(T〉950℃)又快速下降。实验产物分析表明在高温高压下α-石英-β石英相变和岩石部分熔融是岩石Vp异常变化的主要因素。由取样产物的矿物含量和弹性参数,计算了各温度条件下岩石的Vp得出与实验测量相同的波速-温度变化趋势,即Vp随温度升高先缓慢降低,接着快速降低后又急剧升高,最后又快速减小。实验测量和理论计算对比研究表明,通过高温高压下岩石中的物相变化观测结果进行岩石波速的计算,是检验岩石弹性波速测量结果和研究地球内部地震波结构的一种有效方法。 相似文献