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101.
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103.
A new approach to GPS ambiguity decorrelation 总被引:13,自引:1,他引:12
Ambiguity decorrelation is a useful technique for rapid integer ambiguity fixing. It plays an important role in the least-squares
ambiguity decorrelation adjustment (Lambda) method. An approach to multi-dimension ambiguity decorrelation is proposed by
the introduction of a new concept: united ambiguity decorrelation. It is found that united ambiguity decorrelation can provide
a rapid and effective route to ambiguity decorrelation. An approach to united ambiguity decorrelation, the HL process, is
described in detail. The HL process performs very well in high-dimension ambiguity decorrelation tests.
Received: 9 March 1998 / Accepted: 1 June 1999 相似文献
104.
摘要:皖西中、下三叠统为一套碳酸盐岩沉积。从下往上,其沉积环境经历了从盆地-开阔陆棚-开阔台地-局限台地-潮上蒸发台地这样一个海水逐渐变浅、盐度不断增高的环境演化序列.据露头剖面分析,这套碳酸盐岩地层可分成3个层序。层序均由低水位、海进和高水位体系域组成,特征明显。据其岩性特征及准层序的叠置方式,识别出了追赶碳酸盐体系(catchupcarbonatesystem)和并进碳酸盐体系(keepupcarbonatesystem)。 相似文献
105.
106.
Xue Yang Wu Yiping Miao Fasheng Li Linwei Liao Kang Ou Guangzhao 《Stochastic Environmental Research and Risk Assessment (SERRA)》2020,34(2):311-329
Stochastic Environmental Research and Risk Assessment - Conventional landslide analyses, based on deterministic methods or simple random variable methods, cannot consider the spatial variability... 相似文献
107.
以一维分层连续介质大地电磁有限元模拟为例,应用Mathematica软件计算系数矩阵。节约了大量的推导时间。确保快速、准确地得到有限元系数矩阵。展示了mathematica软件在计算有限单元系数矩阵中的强大功能。 相似文献
108.
This paper reports on the discovery that an eclipsing binary system, EPIC 202843107, has aδ Scuti variable component. The phased light curve from the Kepler space telescope presents a detached configuration. The binary modeling indicates that the two component stars have almost the same radius and may have experienced orbital circularization. Frequency analyses are performed for the residual light curve after subtracting the binary variations. The frequency spectrum reveals that one component star is a δ Scuti variable. A large frequency separation is cross-identified with the corresponding histogram, the Fourier transform and the echelle diagram method. The mean density of the δ Scuti component is estimated to be 0.09 g cm~(-3) based on the large separation and density relation. Systems like EPIC 202843107 are helpful to study the stellar evolution and physical state of binary stars. 相似文献
109.
残余和现今应力场重迭法预测强震危险时区 总被引:3,自引:0,他引:3
以红河断裂带测区为例,用X射线法测量了测区的古构造残余应力场及其应变能密度场,用有限单元法计算了测区在两种边界条件下的水平最大剪应力场,用实验和理论证明了古构造残余主压应力大小和方向对岩石破坏、破裂扩展和震级的影响。用上述方法预测,松平—南涧、玉溪—开远、普洱为测区内强震危险区段。结合地球自转角速度相对变率的天文观测曲线在时间轴上的外延,预测得1989-1996、1999-2004、2007-2013、2016-2018年为测区内强震危险时段。 相似文献
110.
Gengxin Ou Francisco Munoz-Arriola Daniel R. Uden Derrel Martin Craig R. Allen Nancy Shank 《Climatic change》2018,151(2):303-316
This study investigates the influence of climate change on groundwater availability, and thereby, irrigation across political boundaries within the US High Plains aquifer. A regression model is developed to predict changes in irrigation according to predicted changes in precipitation and temperature from a downscaled dataset of 32 general circulation models (GCMs). Precipitation recharge changes are calculated with precipitation-recharge curves developed for prognostic representations of precipitation across the Nebraska-Colorado-Kansas area and within the Republican River Basin focal landscape. Irrigation-recharge changes are scaled with changes in irrigation. The groundwater responses to climate forcings are then simulated under new pumping and recharge rates using a MODFLOW groundwater flow model. Results show that groundwater pumping and recharge both will increase and that the effects of groundwater pumping will overshadow those from natural fluctuations. Groundwater levels will decline more in areas with irrigation-driven decreasing trends in the baseline. The methodologies and predictions of this study can inform long-term water planning and the design of management strategies that help avoid and resolve water-related conflicts, enabling irrigation sustainability. 相似文献