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 共查询到17条相似文献,搜索用时 78 毫秒
1.
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   

2.
GIS中面元的误差熵模型   总被引:8,自引:0,他引:8  
根据整个线元边缘分布的平均信息熵确定了“ε-带”的宽度,提出了线元的平均误差熵带模型,进一步扩展到面元的误差熵环模型。误差熵环的带宽取构成边界线的各线段误差熵的加权平均值。最后通过算例比较了面元的误差熵环和误差环模型,绘出了它们的可视化图形,得出了一些有益的结论。  相似文献   

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   

4.
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   

5.
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   

6.
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   

7.
在GIS线元的位置不确定性方面,国内外学者已提出了“e-带”、“e-带”、“g-带”、“H-带”等模型,然而就应用而言,由于“e-带”具有不变带宽,因而应用最为广泛。但是“e-带”的宽度往往难以确定,从而限制了它的使用范围。在“H-带”的基础上,提出了根据线元的平均信息熵确定“e-带”宽度的思想,建立了线元的平均熵不确定带,并以此作为线元位置不确定性的度量。  相似文献   

8.
未知分布误差的熵不确定度   总被引:2,自引:1,他引:2  
分析现有估计方法的不足,提出基于最大熵的不确定度估计。所得的指标不受置信水平选取时的主观性影响,适合于GIS中未知分布误差的不确定性度量。  相似文献   

9.
030 30 1 GIS中面元的误差熵模型 /李大军 (武汉大学 )… / /测绘学报 .- 2 0 0 3,32 ( 1) .- 31~ 35根据整个线元边缘分布的平均信息熵确定了“ε -带”的宽度 ,提出了线元的平均误差熵带模型 ,进一步扩展到面元的误差熵环模型 ,误差熵环的带宽取构成边界线的各线段误差熵的加权平均值 ,通过算例进行了比较 ,并绘出了其可视化图形。0 30 30 2 GIS属性数据精度的缺陷率度量的统计模型 /刘春(香港理工大学 )… / /测绘学报 .- 2 0 0 3,32 ( 1) .36~ 41基于抽样检验在测量数据精度分析中的思想 ,提出基于抽样的缺陷率方法 ,对GIS属性…  相似文献   

10.
利用光斑的特性确定激光点位在光斑中的不确定性,将误差熵引入到激光点位不确定性的评价中。根据激光反射特性,确定了激光点位不确定性的概率密度函数,利用信息熵的定义推导了激光点位的信息熵,同时,利用信息熵与误差熵的关系进行了激光点位误差熵的推导,根据误差熵关系式确定了误差熵与光斑面积的线性关系。根据点云光斑实际面积,得到了点云误差熵及每个激光点位的平均误差熵。利用入射角与误差熵之间的关系,分析了入射角对激光点位不确定性的影响程度,确定了扫描的最佳入射角范围。通过设置不同扫描间隔得到的点云数据,验证了利用误差熵对点云不确定性进行评价的可行性。  相似文献   

11.
Positional error of line segments is usually described by using “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 donut 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   

12.
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   

13.
Spatial data uncertainty can directly affect the quality of digital products and GIS-based decision making. On the basis of the characteristics of randomicity of positional data and fuzziness of attribute data, taking entropy as a measure, the stochastic entropy model of positional data uncertainty and fuzzy entropy model of attribute data uncertainty are proposed. As both randomicity and fuzziness usually simultaneously exist in linear segments, their omnibus effects are also investigated and quantified. A novel uncertainty measure, general entropy, is presented. The general entropy can be used as a uniform measure to quantify the total uncertainty caused by stochastic uncertainty and fuzzy uncertainty in GIS.  相似文献   

14.
Spatial data uncertainty can directly affect the quality of digital products and GIS-based decision making. On the basis of the characteristics of randomicity of positional data and fuzziness of attribute data, taking entropy as a measure, the stochastic entropy model of positional data uncertainty and fuzzy entropy model of attribute data uncertainty are proposed. As both randomicity and fuzziness usually simultaneously exist in linear segments, their omnibus effects are also investigated and quantified. A novel uncertainty measure, general entropy, is presented. The general entropy can be used as a uniform measure to quantify the total uncertainty caused by stochastic uncertainty and fuzzy uncertainty in GIS.  相似文献   

15.
Spatial data uncertainty can directly affect the quality of digital products and GIS-based decision making. On the basis of the characteristics of randomicity of positional data and fuzziness of attribute data, taking entropy as a measure, the stochastic entropy model of positional data uncertainty and fuzzy entropy model of attribute data uncertainty are proposed. As both randomic-ity and fuzziness usually simultaneously exist in linear segments, their omnibus effects are also investigated and quantified. A novel uncertainty measure, general entropy, is presented. The general entropy can be used as a uniform measure to quantify the total un-certainty caused by stochastic uncertainty and fuzzy uncertainty in GIS.  相似文献   

16.
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  
汤仲安 《测绘工程》2005,14(4):11-13,22
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   

17.
This paper describes three aspects of uncertainty in geographical information systems (GIS) and remote sensing. First, the positional uncertainty of an area object in a GIS is discussed as a function of positional uncertainties of line segments and boundary line features. Second, the thematic uncertainty of a classified remote sensing image is described using the probability vectors from a maximum likelihood classification. Third, the "S-band" model is used to quantify uncertainties after combining GIS and remote sensing data.  相似文献   

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