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181.
Rebecca N. Michaelis 《Algebra Universalis》1991,28(1):40-47
Presented by Walter Taylor. 相似文献
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Repeated cycles of plating and stripping using a mercury-coated graphite electrode in raw sea water show increasing negative errors for copper while lead and cadmium are unaffected. This phenomenon, which is not observed in acidified sea water, is attributed to formation of electroinactive Cu(I) species on the electrode. 相似文献
184.
Stability analysis of the G-algorithm and a note on its application to sparse least squares problems
J. L. Barlow 《BIT Numerical Mathematics》1985,25(3):507-520
The G-algorithm was proposed by Bareiss [1] as a method for solving the weighted linear least squares problem. It is a square root free algorithm similar to the fast Givens method except that it triangularizes a rectangular matrix a column at a time instead of one element at a time.In this paper an error analysis of the G-algorithm is presented which shows that it is as stable as any of the standard orthogonal decomposition methods for solving least squares problems. The algorithm is shown to be a competitive method for sparse least squares problems.A pivoting strategy is given for heavily weighted problems similar to that in [14] for the Householder-Golub algorithm. The strategy is prohibitively expensive, but it is not necessary for most of the least squares problems that arise in practice.The research was supported by the National Science Foundation under contract no. MCS-8201065 and by the Office of Naval Research under contract no. N0014-80-0517. 相似文献
185.
Rebecca Finley Detweiler 《Journal of voice》1994,8(4):303-313
Since its introduction, the Sundberg model of the laryngeal system as the resonance source of the singer's formant has gained wide acceptance. However, no studies directly testing this hypothesis in vivo have previously been reported. Thus, the present study was undertaken to test this hypothesis on three classically trained professional male singers. The vocal behaviors of the singer-subjects were evaluated during modal and pulse register phonation via magnetic resonance imaging, strobolaryngoscopy, and acoustic analysis. Results indicated the subjects did not achieve the laryngopharyngeal/laryngeal outlet cross-sectional area ratio requisite to the model and that the formant remained robust in pulse register phonation. It was concluded that these subjects' behaviors were not consistent with Sundberg's model and that the model was inadequate to account for the generation of the singer's formant in these three subjects. 相似文献
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This paper reviews the use of lipid vesicles as model membranes in capillary electrophoresis (CE). The history and utility of CE in the characterization of microparticles is summarized, focusing on the application of colloidal electromigration theories to lipid vesicles. For instance, CE experiments have been used to characterize the size, surface properties, enclosed volumes, and electrophoretic mobilities of lipid vesicles and of lipoprotein particles. Several techniques involving small molecules or macromolecules separated in the presence of lipid vesicles are discussed. Interactions between the analytes and the lipid vesicles - acting as a pseudostationary phase or coated stationary phase in electrokinetic chromatography (EKC) - can be used to obtain additional information on the characteristics of the vesicles and analytes, and to study the biophysical properties of membrane-molecule interactions in lipid vesicles and lipoproteins. Different methods of determining binding constants by EKC are reviewed, along with the relevant binding constant calculations and a discussion of the application and limitations of these techniques as they apply to lipid vesicle systems. 相似文献
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