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31.
The topic of this paper is regression models based on designed experiments, where additional spectroscopic measurements are also available. This particular case describes a situation with two spectral blocks with no natural order: The blocks are parallel. Three methods are described, which combine least squares regression of the design variables with PCA or PLS on the spectra. The methods properties are explored in two simulation studies based on real experiments. The results show that the methods are equal when it comes to prediction, but interpretability varies. One of the methods, LS‐ParPLS, is especially interesting when it comes to interpretability because it splits the spectral information into two parts; information that is common in both blocks and information that is unique for each block. Copyright © 2008 John Wiley & Sons, Ltd.  相似文献   
32.
线性回归估计相合性问题的新进展   总被引:3,自引:0,他引:3  
金明仲  陈希孺 《数学进展》1996,25(5):389-399
本文综述了近年来线性回归最小二乘仗霜合性问题的一些新进展,对在误差方差无限的情况下这种估计的特殊表现作了论述,并提出了若干尚未解决的问题。  相似文献   
33.
基于Matlab的等效电子耦合原子态的矩阵计算   总被引:6,自引:2,他引:4  
用专门处理矩阵的Matlab语言编程,用矩阵的思想给出了计算等效电子LS耦合原子态的计算方法.具体计算了h10电子组态的耦合原子态.  相似文献   
34.
A microbial sensor for rapid determination of the concentration of biodegradable pollutants in wastewater has been developed using the salt-tolerant yeast Arxula adeninivorans LS3 immobilized by gel entrapment with poly (carbamoyl) sulfonate hydrogel (PCS gel) on a Clark-type oxygen electrode. This sensor needs 5min for every measurement instead of 5 days for BOD5. The sensor has a linear response of up to 550mgL–1 BOD with a correlation of coefficient R2=0.9785. The detection limit was calculated to be 2.1mgL–1 BOD equivalents, and the determination limit was 6.0mgL–1 BOD equivalents. The high tolerance to salt of the Arxula adeninivorans LS3 strain prevents the inactivation of cells caused by the seawater from affecting the measurements. In a 24-hour comparative study using real wastewater samples from an international college situated in Hong Kong, the microbial sensor showed a very good correlation (R2=0.9134) with the standard BOD5 method and truly reflected the life cycle of the college people. The microbial sensor allows almost ideal real-time monitoring in water pollution and degradation.  相似文献   
35.
1.IntroductionConsideralinearregressionmodelwhereK,xi,doandeiaretheobservationofthetargetvariable,aknownHvector,theunknownparametervector,andtherandomerror,respectively.LetpbeaconvexfunctiondefinedonRI.TheM-estimateofpo,tobedenotedbyac,isdefinedasaminimizingpointofthefunctionH(P)=ZP(K--x:g).Denotetheleftandrightderivativesofpbyop--andi=1op .Regardingtheweakconsistencyofac,Zhao,RaoandChenll]establishedthefollowingresult:TheoremA.Lete15eZt'belid.Supposethatthereexistsfunctionop,satisfy…  相似文献   
36.
37.
Wen Jing Qi  Li Qiang Chen 《Talanta》2010,80(3):1400-9503
A facile solution-phase synthesis route of highly uniform Cu2O nanospheres (Cu2O NPs) with the size of 57.7 ± 4.7 nm was developed, and then the nanoparticles were applied to live cell imaging under a common dark-field microscope. Starting from copper(II) salts, the synthesis of Cu2O NPs was made in the presence of cetyltrimethylammonium bromide (CTAB) by reducing the copper(II) with sodium borohydride (NaBH4) in aqueous medium and by aging process in the air. Monitoring of morphology evolution process of Cu2O NPs with scanning electron microscopy (SEM) and measuring of the UV-visible spectra showed that the synthesis of Cu2O NPs follows the reduction-oxidation coupled process of Cu2+ into Cu0 species at first and then the resulted Cu0 species into Cu2O NPs in the air. Light scattering (LS) features have been measured with a common spectrofluorometer and a common dark-field microscope, and it was found that the as-prepared Cu2O NPs display strong blue scattering light and can be applied for cell imaging. If incubated with human bone marrow neuroblastoma, transferrin-conjugated Cu2O NPs can get into the cells and show strong pure blue light in cytoplasm. Further investigations showed that the Cu2O NPs could be applied for probes for conformation of proteins.  相似文献   
38.
阐述了用Matlab的函数推求等效电子LS耦合的光谱项的方法,具体推求了3个等效d电子和6个等效f电子组态的光谱项。  相似文献   
39.
Though EV model is theoretically more appropriate for applications in which measurement errors exist, people are still more inclined to use the ordinary regression models and the traditional LS method owing to the difficulties of statistical inference and computation. So it is meaningful to study the performance of LS estimate in EV model. In this article we obtain general conditions guaranteeing the asymptotic normality of the estimates of regression coefficients in the linear EV model. It is noticeable that the result is in some way different from the corresponding result in the ordinary regression model.  相似文献   
40.
关于LS耦合的适用条件   总被引:3,自引:1,他引:2  
许国材 《大学物理》1998,17(6):9-13
通过经典电磁学的数量级估计和量子力学的计算表明,多电子原子中适用LS耦合的条件应为:电子的自旋-轨道磁相互作用小于电子间的剩余静电相互作用而非小于电子的自旋-自旋与轨道-轨道磁相互作用。  相似文献   
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