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851.
852.
Both title compounds were obtained in four steps from 2R, 3R-dihydroxy-4R-valerolactone 5 readily available from D-ribonolactone. 相似文献
853.
854.
Supported in part by NSF grant DMS-9204093 相似文献
855.
First, the problem of solving a system of linear equations is shown to be equivalent to the computation of biorthogonal polynomials.
The bordering method is a procedure for solving recursively a sequence of linear systems with increasing dimensions and it
gave rise to a recurrence relationship between two adjacent families of biorthogonal polynomials. Of course, one relation
is not sufficient for computing two families. However, in some particular cases, a second recurrence relationship exists between
these biorthogonal polynomials thus leading to procedures for solving recursively such linear systems with increasing dimensions.
The cases of Hankel and Toeplitz matrices are treated in details.
Conferenza tenuta da C. Brezinski il 12 ottobre 1993 相似文献
856.
857.
We present a calculus whereby the curvature of a geometry arising from any generalized twistor correspondence is related to an obstruction-theoretic classification of the infinitesimal neighborhoods of submanifolds of its twistor space. The crux of the argument involves a relation between Kodaira—Spencer maps and the Penrose transform. 相似文献
858.
Nadine Gabas Noël Hiquily Claude Lagurie 《Particle & Particle Systems Characterization》1994,11(2):121-126
This study deals with the size measurement of non-spherical particles by the laser diffraction technique. Size analyses of three sets of identical metallic bodies (cubes, tablets and cylinders) were performed by means of a Malvern 2600 instrument. The results prove that under the operating conditions chosen and in the case of anisometric objects, the mean total surface area is not measurable either because the Malvern software, strictly valid for spheres, is not applicable to such particles or because the particles adopt preferential orientations in the measurement cell. Further, a way of processing diffraction data is proposed in order to determine two characteristic dimensions of identical anisometric particles. It is based on the measurement of the minimum and maximum projected surface areas of the particles. The experimental results obtained with our particles show the procedure to be reliable. 相似文献
859.
860.
Claude Lefèvre Vasilis Papathanasiou Sergey Utev 《Annals of the Institute of Statistical Mathematics》2002,54(4):731-742
This paper is concerned with a Rodrigues' formula for generating new classes of polynomials. The associated density functions belong to the family of generalized Pearson curves, which extends the classical Pearson family. Various properties of these polynomials (degree, orthogonality ...) are investigated and then exploited to derive several related results, especially characterizations, in probability. 相似文献