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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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Carey et al.utilized principal components analysis (PCA) to analyze frequency shift data obtained frompiezoelectric sensors formed by coating quartz crystals with 27 different GC stationary phases and testedusing 14 analytes.The objective of the analysis was to determine an optimal reduced set of coatings fordetection of the analytes.The results were correlated with those obtained from cluster analysis.In thispaper the data are re-analyzed using correspondence analysis (CA).The advantage of using CA includea symmetric treatment of sensor coatings and analytes and better identification of the representation ofthe analytes in terms of the detection components.The results obtained by the conjunctive use of PCA,a varimax rotation and cluster analysis were obtained by CA.  相似文献   
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长江河口区平均海面季节性变化的分析   总被引:4,自引:0,他引:4  
沈健  王宝灿 《地理学报》1990,45(4):441-450
长江河口区的月平均海面变化主要受径流及其它海洋水文气象因子的作用,而且具有明显的季节性变化。本文为了探讨月平均海面时空变化的规律,运用了经验特征函数,对月平均海面的时空变化进行分解。以三个相互正交模型,估算了水文气象因子在月平均海面变化中所起的作用。  相似文献   
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