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The directionality of thermal radiance of a homogeneous isothermal non-black plane surface is totally decided by its directional emissivity, which depends on the complex dielectric constant and roughness of surface. It can be expressed by This paper proves that it is necessary to express emissivity by a matrix when a target becomes an inhomogeneous non-isothermal open complex with complicated inner geometric structure. The matrix describes the inner radiative interaction among components accurately and also expresses its thermal radiative directionality and structural characteristics completely. Advantages of matrix expression are as follows: first, the physical mechanics of effective emissivity of an open complex is described in a simple and perfect way; second, it becomes easy to understand the principle and method to retrieve components temperature from multi-angle thermal remotely sensed data; and third, the differences of directionalities between an open complex and a homogeneous isothermal non-black plane body are expressed by just using an effective emissivity matrix instead of an emissivity vector. Formula in classic physics is only the special case of matrix expression; therefore, the matrix is a universal unconditional expression to describe the directionality of thermal radiance. 相似文献
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捷联惯性导航系统中,根据四元数与直余弦矩阵的关系可以得到3种转换矩阵。充分分析了这3种转换方案所产生的误差。并在恒定角速率下对3种不同转换矩阵中漂移误差、不对称误差和刻度误差进行评估,最后通过仿真验证了分析结果。 相似文献
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Dean S. Oliver 《Mathematical Geology》1998,30(7):911-933
In reservoir characterization, the covariance is often used to describe the spatial correlation and variation in rock properties or the uncertainty in rock properties. The inverse of the covariance, on the other hand, is seldom discussed in geostatistics. In this paper, I show that the inverse is required for simulation and estimation of Gaussian random fields, and that it can be identified with the differential operator in regularized inverse theory. Unfortunately, because the covariance matrix for parameters in reservoir models can be extremely large, calculation of the inverse can be a problem. In this paper, I discuss four methods of calculating the inverse of the covariance, two of which are analytical, and two of which are purely numerical. By taking advantage of the assumed stationarity of the covariance, none of the methods require inversion of the full covariance matrix. 相似文献
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Mineral-bituminous matrix(MBM) makes up a major part of source rocks,but its potential in hydrocarbon generation is uncertain,Mineral and organic (Maceral and kerogen) compositions,organic maturity and fluorescence of MBM are studied based on source rock samples from eastern Jiuquan(Jiudong)Basin.The results show that MBM is dominated by inorganic minerals and among the small percentage of organic components those of secondary origins are predominant over the primary species.This strongly indicates that the significance of MBM in hydrocarbon generation is limited. 相似文献
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甘孜生康剪切混杂岩带,它初始发育在陆棚与大陆基之间,是“再生”小洋盆关闭、俯冲-碰撞乃至斜冲剪切、左行走滑综合作用的产物。带内由不同岩性,不同层位,不同时代的构造岩块与遭受强烈剪切变形的粉砂岩、板岩“基质”组合而成。宏观上,无层无序,块体内有序,是造山带特有的非史密斯地层体。 相似文献
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A numerical approach to the earthquake ground motion analysis is proposed for regions where no accelerograms are available. Using Haskell matrix techniques, the response spectra of a layered substratum for SV waves were calculated and then multiplied by the spectra corresponding to Brune's type pulses. The ground acceleration spectra were obtained for different angles of pulse incidence at the substratum base. The spectrum shape depends upon the substratum response and the pulse shape, while its level was related to the maximum ground acceleration corresponding to the expected maximum intensity. Transformation of the ground spectra into the time domain produced numerical accelerograms for horizontal and vertical components and for different angles of pulse incidence. Finally, a standard statistical procedure was applied to obtain the design response spectra used in engineering applications. 相似文献