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991.
在分析分形维和马尔可夫随机场两种主要纹理模型法的基础上,提出了先用马尔可夫随机场方法进行纹理分类,再用分形维方法对那些具有相同马尔可夫随机场模型及参数值相近的纹理影像进行分类的方法。该方法不仅能提供出影像纹理的纹理基元,还能给出影像粗糙性、自相似程度,减少了纳伪误差。 相似文献
992.
地震剖面随机分形插值方法 总被引:10,自引:3,他引:7
本文讨论了随机分形插值方法及其在地震资料处理中的应用。实验结果表明,随机分形插值方法是提高地震分辨率的简单有效方法。 相似文献
993.
A concept of prediction of rock and gas outbursts 总被引:2,自引:0,他引:2
T. Cyrul 《Geotechnical and Geological Engineering》1992,10(1):1-17
Summary The paper presents the prediction and modelling of rock and gas outbursts, since these are good examples of multivariable hazards in rock masses. A critical evaluation of outburst modelling is discussed and the need for system modelling of complex natural hazards is pointed out. The concept of an outburst as an event in a random field is presented. Within this conceptual framework a non-physical approach to outburst prediction, making use of measured data, is demonstrated. The approach uses the cause-effect black box scheme to study relations between the causes and effects of outbursts. The system is assumed to be described by relations of a monotonic type, between causes and effects of outbursts. These assumptions are verified using data from the Lower Silesian Coal Basin (Poland). 相似文献
994.
A vivariate probability density function (pdf),f(x
1,x
2), admissible for two random variables (X
1,X
2), is of the form
相似文献
995.
J. R. Resnick 《Pure and Applied Geophysics》1990,132(1-2):49-65
A plane-wave signal traveling at normal incidence through the earth's sedimentary layers attenuates, spreads, and changes waveform as it propagates, partly in response to stratigraphic filtering resulting from the buildup in the medium of intrabed multiples caused by the layering, and partly in response to absorption. This paper consists of a review of one-dimensional stratigraphic filtering. The action of stratigraphic filtering resembles that of absorption, and the filter's spectrum can be characterized by an effective quality factor. A comparison between the spectra of field data and synthetic data derived from absorption-free one-dimensional models suggests that in some geologic formations, stratigraphic filtering causes a significant fraction of the total attenuation evident on seismic records. In such studies, however, the simplicity of one-dimensional models leaves some uncertainty regarding the generality of the results. Nonetheless, one-dimensional stratigraphic filtering can serve as a useful metaphor that provides insight into the workings of more complex multi-dimensional scattering models. 相似文献
996.
运用两类Stirling数的概率表示得到两类Stirling数的一些特殊值,证明并得到了一些有关两类Stirling数的新的递推公式和恒等式,从而丰富发展了孙平、王天明关于“Stirling数的概率表示和应用”中的内容。 相似文献
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999.
AbstractIn this article, a simplified approach for the reliability-based design of laterally loaded drilled shafts considering the spatial variability of soil property is presented. This simplified approach utilizes a conventional reliability method implemented using the variance reduction technique. An algorithm for back-calculating the reduction factor and characteristic length for various shaft slenderness ratios is proposed. This simplified approach can yield responses for drilled shafts that are equivalent to those obtained using random field modeling (RFM), which is a far more complex process. The simplified approach does not require the knowledge of random field theory and can be an efficient design tool in geotechnical engineering practice. 相似文献
1000.
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