共查询到19条相似文献，搜索用时 93 毫秒
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矢量GIS平面一般曲线等概率密度误差模型 总被引：1，自引：0，他引：1
基于数值分析、经典概率论和线状实体误差分布机理，定义了矢量GIS平面一般曲线等概率密度误差模型的概念，提出了平面一般曲线等概率密度误差模型尺度因子的概念和确定方法，姑合平面一般曲线落入其相应等概率密度误差模型内的概率算法和概率置信水平，确定了尺度因子的具体数值，给出了平面一般曲线等概率密度误差模型的形状与规模。 相似文献
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基于法平面的GIS平面随机线元概率算法 总被引：6，自引：1，他引：6
基于概率论与数值分析,研究基于线元法平面的GIS中平面随机线元落入其相应误差模型内的概率算法,通过实例计算与可视化分析,比较基于误差模型建模机理的概率算法,并得出如下结论:基于线元法平面的概率算法与基于误差模型建模机理的概率算法对GIS中随机线元误差模型的建模是等价的,而且对于GIS中一般曲线的误差模型建模而言,前者具有通用性。 相似文献
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从空间解析几何学的角度,基于平面随机线元等概率密度误差模型建模原理,研究了矢量GIS空间随机线元位置不确定性误差模型的建模原理,提出并证明了“空间线元上任意点Pt处用以构建空间线元等概率密度误差模型体的误差椭球三轴长在数值上等于相应空间点处标准误差椭球对应三轴长的[m(λA,t)]2倍,且该空间点处误差椭球三轴线各自对应的空间向量方位保持不变”的重要结论,这对于矢量GIS空间线状实体位置不确定性误差模型的建模具有指导意义。 相似文献
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矢量GIS平面随机线元等概率密度误差模型的概率算法 总被引：1，自引：1，他引：1
研究了基于误差模型包络点的概率算法，并与基于随机线元法平面的概率算法进行了比较。实例计算与可视化分析发现，两种概率算法对应的概率计算值近似，Tepdem及其边界包络线一致，且前者适用于随机线元，而后者更具有通用性。 相似文献
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线元点位误差带的“纺锤形”模型 总被引：1，自引：0，他引：1
对当前GIS界流行的以点位误差描述线元位置不确定性的误差带理论提出相反的观点。最早提出的线元误差带理论为"ε-带"模型,后来又提出了"E-带"模型和在其基础上发展的"G-带"模型。后两者均认为以控制点点位误差描述的线元的误差带的基本形状呈"哑铃"形,即认为线元上端点的位置不确定性大于端点之间的点的位置不确定性。笔者的看法与此相反,笔者认为线元上两控制点之间的点的位置不确定性应大于控制点的位置不确定性,且在两控制点的中间达到最大,即线元误差带的基本形状应为"纺锤形"而不是"哑铃形"。 相似文献
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平面随机线元等概率密度误差模型边界包络线 总被引：1，自引：0，他引：1
线状实体误差模型包络线既是GIS位置不确定性研究的重要内容,又是GIS可视化研究的关键指标.为了充分利用计算机技术求解符合GIS精度要求的误差模型包络线,基于文献[1,2]中探讨过的等概率密度误差模型建模机理和数值算法,研究了平面随机线元等概率密度误差模型边界包络线的确定原理和计算方法,并通过实例辅以可视化分析,验证了原理的正确性和可操作性. 相似文献
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GIS中三维空间直线的误差熵模型 总被引：1，自引：0，他引：1
从信息熵的角度提出了三维空间直线的误差熵模型，该模型由以垂直直线的平面误差熵为半径的圆柱体和两端点的误差球组成，是一种完全确定的度量空间线元不确定性的模型。理论分析与实验表明，本文所提出的模型具有较好的效果。 相似文献
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LI Zhicai XU Caijun 《地球空间信息科学学报》2005,8(3):225-229
On the basis of the dislocation theory and gravity observation, a joint inversion model is presented with a fitting factor A scaling amplitudes between the gravity and GPS observation data. The test results show that the new joint model is better than that taking the scale factor ）, as a constant from the inversion result of MSE （mean square error）. In addition, the random cost method used in the inversion algorithm is revised and improved, which shows that the improved random cost method can easily get the local minimum value and greatly decrease the iteration steps. 相似文献
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平差系统的模型误差及其识别方法研究 总被引：2，自引：0，他引：2
论述了模型误差影响参数估值的一些理论问题,指出了随机模型误差和函数模型误差之间的相互作用和转化。为讨论平差系统最优模型的选取,给出了与现有文献将模型误差纳入平差系统的思路不同的一个估计和识别模型误差的理论基础公式,由此导出了相应的实用公式,给出了平差系统模型的优选方法。 相似文献
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Wenting Quan 《Journal of the Indian Society of Remote Sensing》2014,42(3):495-503
In this study, a theoretical model for studying the scaling effects on the two-band ratio of red to near-infrared band (TBRRN) is suggested. The model is used to explain the relationship between scaling error and local scale error; the results revealed that a special scale scaling procedure can be divided into a series smaller scale scaling procedures, and the total scaling error is the sum of the scaling error of these series’ smaller scale scaling procedure. Consequently, under the condition that the local scale is adequately fine, the total scale error at the target scale may be estimated accurately. In order to understand the mechanisms associated with scale in practical remote sensing, TBRRN data with 250 m and 1 km resolution is estimated from MODIS data at 645 and 859 nm, retrieved on September 1, 2009, in the Yellow River estuary, China. It is found that the TBRRN estimated from the 1 km resolution MODIS data is ~2.94 % smaller than as estimated from the 250 m MODIS data. The large scaling error distributes neither in the turbid waters, nor in the low suspended sediment regions, but instead in the high-low suspended sediment concentration transitional zone, which may be attributed to the spatial variable of suspended sediment in the transitional zone. This paper also points out that, owing to the importance of total scale error in achieving NASA’s mission in oceanic remote sensing, the way in which to conveniently and precisely estimate the total scale error of remote sensing parameters may potentially be an important topic in the field of oceanic remote sensing, both in present research and in the future. 相似文献
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强污染单历元GPS形变信号的提取和粗差识别 总被引：6，自引：0，他引：6
阐述了小波分析技术用于强污染GPS单历元形变信号处理的基本原理及其实现方法。以含少量粗差的低信噪比形变信号为例 ,研究了基于Mallat分解和合成算法 ,分离信号趋势项并进行粗差识别的技术。采用小波软阈值降噪的方法去除强污染数据中的随机噪声 ,降噪效果远好于中值滤波。最后对识别的粗差信息进行线性修复 ,获得了令人满意的形变信号 相似文献
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The mathematic theory for uncertainty model of line segment are summed up to achieve a general conception, and the line error band model of εp is a basic uncertainty model that can depict the line accuracy and quality efficiently while the model of εm and error entropy can be regarded as the supplement of it. The error band model will reflect and describe the influence of line uncertainty on polygon uncertainty. Therefore, the statistical characteristic of the line error is studied deeply by analyzing the probability that the line error falls into a certain range. Moreover, the theory accordance is achieved in the selecting the error buffer for line feature and the error indicator, The relationship of the accuracy of area for a polygon with the error loop for a polygon boundary is deduced and computed. 相似文献
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Single Epoch GPS Deformation Signals Extraction and Gross Error Detection Technique Based on Wavelet Transform 总被引：1，自引：0，他引：1
WANG Jian GAO Jingxiang XU Changhui 《地球空间信息科学学报》2006,9(3):187-190
IntroductionGPS technique is widely used for deformationmonitoring thanks for the high precision. Usual-ly , there are three working modes associatedwith GPS deformation observation: periodicalGPS deformation monitoring net , GPS monito-ring array and rea… 相似文献
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The mathematic theory for uncertainty model of line segment are summed up to achieve a general conception, and the line error band model of ?σ is a basic uncertainty model that can depict the line accuracy and quality efficiently while the model of ?m and error entropy can be regarded as the supplement of it. The error band model will reflect and describe the influence of line uncertainty on polygon uncertainty. Therefore, the statistical characteristic of the line error is studied deeply by analyzing the probability that the line error falls into a certain range. Moreover, the theory accordance is achieved in the selecting the error buffer for line feature and the error indicator. The relationship of the accuracy of area for a polygon with the error loop for a polygon boundary is deduced and computed. 相似文献