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We consider the problem of resolving the total luminescence spectra of two-component mixtures.Non-negativity of the constituent spectra is commonly used as a criterion to accomplish this resolution,but its application seldom leads to unique answers. Sometimes, the condition must be relaxed because nosolution satisfying non-negativity exists. In these cases judgments must be made concerning which partsof the spectra will be allowed to go negative and by how much. The wavelength component vectorgramn (WCV) is presented here as a tool for assisting theexperimenter in making these judgments. Even when non-negative resolutions exist, it may happen thatresolutions with slight negative elements will more closely match the spectra of the pure constituents.The WCV can also be used as a tool for detecting these cases. The methodology is illustrated with realdata from a two-component mixture. 相似文献
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Starting from the unit-impulse response matrix of the unbounded medium, a discrete-time formulation permitting the recursive evaluation of the interaction forces and a continuous-time formulation yielding property matrices corresponding to a model with a finite number of degrees of freedom are discussed. This is achieved using the balancing approximation method which is easily automated, guarantees stability and leads to highly accurate results. © 1998 John Wiley & Sons Ltd. 相似文献
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给出2类双结构矩阵的标准型。作为应用,还利用新得出的标准型对这2类双结构矩阵特征值问题发展了结构算法,其中对第一类双结构矩阵特征值问题发展了只用实运算的结构算法。 相似文献
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?????????????С???????????????????????С???????????????С???????????????????????????????????????С?????????????????????????С??????????????????й?????????????????????????y????????? 相似文献
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扼要地介绍了非球形粒子光散射的散射矩阵元素按广义球函数展开的基本理论,以及球形粒子散射矩阵元素间的关系。在此基础上较详细地阐述了计算展开系数的方法以及在程序研制中所遇到的一些问题。最后,对非球形的Chebyshev粒子光散射的散射矩阵元素的展开系数进行了计算,结果表明数值技术和计算的正确性。 相似文献
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Development of Seismic Risk Scenarios Based on a Hybrid Method of Vulnerability Assessment 总被引:6,自引:5,他引:6
A hybrid methodology of vulnerability analysis is presented, involving elements from both empirical and theoretical methods. A model for correlating analytically calculated structural damage indices to loss (in monetary terms) is also proposed and calibrated against available statistical data. Probability damage matrices derived using this methodology are incorporated into a cost-benefit model tailored to the problem of estimating the feasibility of seismically rehabilitating the existing stock of reinforced concrete buildings in Thessaloniki, Greece. Losses calculated using the suggested procedure are found to be in good agreement with losses incurred during the 1978 Thessaloniki earthquake. The results of the present study also indicate that benefit/cost ratios for reinforced concrete buildings are quite low. Hence, it appears that a pre-earthquake strengthening programme is not economically justifiable. 相似文献
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A differential approach to map comparison and integration is presented utilizing the variance-covariance matrices of polynomial trend surfaces. The approach is based on the statistics presented in the trend-surface computer program, CORSURF. Examples in south-central Kansas and the Maracaibo Basin in Venezuela are presented to show how the technique could be used in basinanalysis studies. 相似文献
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