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1.
Positional error of line segments is usually described byusing “g-band”,however,its band width is in relation to the confidence level choice.In fact,given different confidence levels,a series of concentric bands can be obtained.To overcome the effect of confidence level on the error indicator,by introducing the union entropy theory,we propose an entropy error ellipse index of point,then extend it to line segment and polygon.and establish an entropy error band of line segment and an entropy error do-nut of polygon.The research shows that the entropy error index can be determined uniquely and is not influenced by confidence level,and that they are suitable for positional uncertainty of planar geometry features.  相似文献   

2.
GIS中线元的误差熵带研究   总被引:6,自引:3,他引:3  
基于现有的线元位置不确定性模型大多与置信水平的选取有关,而置信水平的选取带有一定程度的主观性,因而不能惟一确定,引入信息熵理论,提出了线元的误差熵带模型,并将它与“E-带”进行了比较,计算了落入其内的概率。该模型根据联合熵惟一确定,与置信水平的选取无关。  相似文献   

3.
The mathematic theory for uncertainty model of line segment are summed up to achieve a general conception, and the line error hand model of εσ 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   

4.
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   

5.
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   

6.
熵理论在确定点位不确定性指标上的应用   总被引:3,自引:0,他引:3  
分析了传统点位不确定性指标的局限性,基于信息论中的联合熵和最大熵定理导出了n维随机点熵不确定指标以及落入其内概率的统一公式;提出了以熵误差椭圆与熵误差椭球作为2维、3维GIS中点元的位置不确定性度量指标。提出的熵指标具有唯一确定、不受置信水平选取的主观性影响等特点,适合于度量未知分布的点位不确定性。  相似文献   

7.
1 Introductionffe well-for Meanboha Eno(MSRE),having advanop of talculang ndy,has bo widdyed to m the W of pont ednates inGIS' NY and gedop. N, it is Me tDtw the opiW eno Of a pont in whitw dirm-tion, while in praedce there is ned tO for the value ofghH or Of a trint in a peial boon SUCh asthe uha diW. The or curve of a glnt is ableto W twl the diAnbution wttiOn of twnt eno.ln an arbtw dich and it is the nd efhaive edfor dedbing forhed rm Of odnts in SUrVopng..mpneenng(Mithel, 1983…  相似文献   

8.
GIS中空间数据不确定性的混合熵模型研究   总被引:4,自引:0,他引:4  
基于信息理论和模糊集合理论,针对GIS中部分空间数据既具有随机性又具有模糊性的特点,建立了空间数据不确定性的混合熵模型。以GIS中线元不确定性为例,讨论了线元不确定性的统计熵、模糊熵和混合熵估计方法,并针对特例给出了线元不确定性的熵带分布。  相似文献   

9.
为揭示我国SRTM3DEM数据高程精度质量,结合已开展过SRTM3DEM高程精度质量评价工作的局部地区的研究,考虑空间分布情况,选取新疆、辽宁、山东、浙江、海南5个地区的平原、丘陵、盆地、山地等地形区域作为典型研究区,并以1∶5万DEM为假定真值、以1∶25万DEM为参照,通过DEM面误差可视化分析、DEM面误差信息熵模型、中误差模型等方法对SRTM3DEM数据高程精度质量做了分析。计算结果表明我国SRTM3DEM数据高程精度质量受地形影响并存在一定的空间差异性,同时我国范围内SRTM3DEM数据高程精度质量整体上要高于1∶25万DEM。  相似文献   

10.
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   

11.
In this paper, a method to detect corresponding point pairs between polygon object pairs with a string matching method based on a confidence region model of a line segment is proposed. The optimal point edit sequence to convert the contour of a target object into that of a reference object was found by the string matching method which minimizes its total error cost, and the corresponding point pairs were derived from the edit sequence. Because a significant amount of apparent positional discrepancies between corresponding objects are caused by spatial uncertainty and their confidence region models of line segments are therefore used in the above matching process, the proposed method obtained a high F-measure for finding matching pairs. We applied this method for built-up area polygon objects in a cadastral map and a topographical map. Regardless of their different mapping and representation rules and spatial uncertainties, the proposed method with a confidence level at 0.95 showed a matching result with an F-measure of 0.894.  相似文献   

12.
误差熵不确定带模型   总被引:25,自引:2,他引:25  
本文从信息论的基本理论出发,通过熵的极值定理和引入误差熵的概念 ,首次提出了误差熵不确定带模型。该模型与以往的误差模型有着本质的区别。它不是任何意义上的置信带,而是一种完全确定的,与置信水平无关的不确定带模型。  相似文献   

13.
This article presents a new development in measuring the positional error of line features in Geographic Information Systems (GIS), in the form of a new measure for estimating the average error variance of line features, including line segment, polyline, polygon, and curved lines. This average error measure is represented in the form of a covariance matrix derived by an analytical approach. Corresponding error indicators are derived from this matrix. The error of line features mainly results from two factors: (1) an error propagated from the original component points of line features and (2) a model error of interpolation between these points. In this study, a method of average error estimation has been derived regarding the first type error of line features that are interpolated by either linear or cubic interpolation methods. The main contribution of the research is the provision of an error measure to assess the quality of spatial data in application settings. The proposed error models for estimating average error variance of line features in a GIS are illustrated by both simulated and practical experiments. The results show that the line accuracy from a linear interpolation is better than a line interpolated using a cubic model.  相似文献   

14.
首先研究基于εσ模型单一折线段不确定性误差带,导出误差带边界线的解析表达式;然后通过算例分析,针对开折线和闭折线两种情况,由单一折线段误差带边界线的解析表达式,编程绘出位置不确定性随机折线的可视化图形。理论分析和可视化图形表明,在两条相邻折线的公共端点处,前一线段的右误差半圆的半径和后一线段的左误差半圆的半径未必相等,实际分析中需考虑到这种情况。  相似文献   

15.
在研究三维空间线元置信域模型的基础上,分别从三维空间多边形置信域模型和度量方法两个角度研究了三维空间多边形的位置不确定性借鉴三维空间线元的置信域建模原理,提出了三维空间多边形置信域模型;基于积分学原理,提出了三维空间多边形置信域度量模型实例研究结果表明,三维空间多边形置信域度量模型可以应用于工程等领域的质量控制过程.  相似文献   

16.
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   

17.
引入结点度的线/面拓扑关系细分方法与应用   总被引:1,自引:1,他引:0  
周晓光  陈斐  陈军 《测绘学报》2015,44(4):445-452
针对线/面细分拓扑关系研究存在的不足,提出了一种基于结点度的线/面细分拓扑关系描述与计算方法。该方法在定义线/面单元交线并分析其特点的基础上,引入结点度来区分线/面单元交线细分类型。根据单元交线端点在线/面目标组成图形结构中结点度的不同,及线目标在度为3和4的交线端点处是否有相连线段、相连线段位于多边形的边界上、内部或外部4个谓词推导出了21种有意义的线/面交线细分拓扑关系类型。在此基础上分析比较了本文方法与现有方法的异同与优势,举例说明本文方法在复杂线/面细分拓扑关系描述中的应用。最后用Visual C#语言编程实现了该方法,并将其应用到线状道路/面状河流目标间的数据质量检查与修正中,验证可行性。  相似文献   

18.
GIS中直线元内插点精度及对误差带的影响   总被引:1,自引:0,他引:1  
基于误差传播定律,考虑参数r误差影响,推导了线元内插点的精度计算公式,讨论内插点精度对线元误差带的影响,并对影响的结果进行了分析,得到了一些有益的结论。  相似文献   

19.
针对使用传统算法创建网格索引存在遗漏网格的缺点,本文提出一种建立精确网格索引的新算法。该算法基于对线段与其所经过的网格对角线的关系的分析,实现了对线、多边形(包括复杂多边形)目标的精确网格索引。  相似文献   

20.
测量平差问题中,讨论观测量和参数估值时引入熵及熵意义上不确定度区间的概念,并论证了不确定度区间作为评定精度的指标的可行性,进而提出以不确定度区间作为假设检验的置信区间,避免了选取显著性水平α时的非客观因素的影响。给出了t分布,x2分布、F分布不确定度区间的计算公式及相应的数表。  相似文献   

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