Rock-mineral spectrum is a mixture of varied mineral spectra,through which we can obtain informa-tion about its components quickly and conveniently without any damage to the sample.Empirical mode decom-position (EMD)cannot directly decompose source signals from information of the mixture,and independent component analysis (ICA)requires the number of mixed signals to be no less than the number of source sig-nals.Combining these two methods,mixed signals can be decomposed using EMD method to obtain intrinsic mode function (IMF),while certain IMFs together with mixed signals can be used as input data matrix of ICA to obtain the source signals.This method overcomes the shortcomings of IMF and ICA.Studies have shown that,the higher content of source signals contained in the mixed signal,the better estimation can be obtained through EMD and ICA.The number of IMFs that participate in ICA decomposition determines the number of approximation of source signals.The accuracy of source signal estimation increases with the correlation coeffi-cient between IMF and mixed signals.By applying this method to quantitative analysis of rock-mineral spec-trum,information of the component minerals in rock-mineral can be obtained,which improves the efficiency of component analysis in detecting rock-minerals outside.%岩矿光谱由多种矿物光谱混合而成,解译岩矿光谱能够得到岩矿的组分信息,且该方法具有快速、方便、不损坏样品的特点。经验模态分解(empirical mode decomposition,EMD)不能直接分离出混合信号中的源信号,独立成分分析(independent component analysis,ICA)要求混合信号数目不小于其所包括的源信号数目。将 EMD和 ICA两种方法相融合,首先用 EMD 分解混合信号得到本征模态函数(intrinsic mode function,IMF),再选择一定数目的 IMF与混合信号一起组成 ICA的输入数据矩阵,经过 ICA 运算可以获取单一混合信号中的源信号信息,克服了 EMD和 ICA两种方法各自的缺陷。研究表明,综合应用 EMD和ICA方法可以获取单一混合信号中的源信号信息,混合信号中源信号含量越大,得到的源信号近似值越理想。参与ICA分离的IMF数目决定了分离得到的源信号近似值的数目,并且选择的IMF与混合信号相关系数越大,得到的源信号近似值越理想。运用该方法定量分析岩矿光谱,可以获取组成岩矿的矿物信息,比较适用于野外作业岩矿的快速分析鉴定及成分初步分析。
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