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311.
312.
Audrey A S G Lonni Ieda S Scarminio Lucas M C Silva Dalva T Ferreira 《Analytical sciences》2003,19(7):1013-1017
Phytochemical investigation of the aerial parts of three Baccharis species (Asteraceae family) was performed using HPLC and chemometric methods, with the objective of distinguishing between three morphologically very similar species: Baccharis genistelloides Persoon var. trimera (Less.) DC, B. milleflora (Less.) DC and B. articulata (Lam.) Persoon. With the help of Principal Component Analysis (PCA) and variance weights, it was possible to characterize the chromatographic profiles of the alcoholic extracts of the three species. Application of Soft Independent Modeling of Class Analogy (SIMCA) and K-Nearest Neighbor (KNN) methods on a training set of 74 extracts resulted in models that correctly classified all eight samples in an independent test set. 相似文献
313.
A. Touraille 《Algebra Universalis》1995,33(2):196-206
Presented by S. Burris. 相似文献
314.
We give sufficient conditions for a finite permutation groupto contain a fixed-point-free permutation of p-power order fora given prime p. 相似文献
315.
A. M. Gurin 《Journal of Mathematical Sciences》2007,146(1):5505-5508
The number of combinatorially nonequivalent Dirichlet-Voronoi diagrams constructed for the centers of balls in the packing
obtained from the densest lattice packing of equal spheres by a small displacement of the spheres is estimated.
__________
Translated from Fundamentalnaya i Prikladnaya Matematika, Vol. 11, No. 5, pp. 79–84, 2005. 相似文献
316.
A. G. Chentsov 《Russian Mathematics (Iz VUZ)》2007,51(11):55-68
We consider a problem which implies the choice of a solution subject to asymptotic constraints. We represent the results as ultrafilters of the space of ordinary estimates (the space is not necessarily endowed with a topology). This representation corresponds to an abstract attainability problem in its nonsequential asymptotic version. 相似文献
317.
A. M. Raigorodskii 《Journal of Mathematical Sciences》2007,146(2):5723-5730
This work deals with some problems on the embeddings of finite geometric graphs into the random ones. In particular, we study here applications of the random graph theory to the Nelson-Erdös-Hadwiger problem on coloring spaces. 相似文献
318.
A. V. Pukhlikov 《Journal of Mathematical Sciences》2007,140(2):303-320
Combining the connectedness principle of Shokurov and Kollár, we develop a new technique of studying birational maps of natural
Fano fiber spaces. We prove that the only structures of a rationally connected fibration on direct products of typical Fano
varieties are projections onto the factors. In particular, the groups of biregular and birational self-maps of Fano direct
products coincide.
__________
Translated from Fundamentalnaya i Prikladnaya Matematika, Vol. 10, No. 4, pp. 183–206, 2004. 相似文献
319.
A. D. Lapin 《Acoustical Physics》2007,53(1):11-15
The problem of scattering of a Rayleigh wave by a chain of identical closely spaced monopole-dipole resonators with friction is considered. The values of resonator parameters that provide the rejection of the Rayleigh wave are found. The conditions under which the Rayleigh wave is much more efficiently reflected by the dipole resonators than by the monopole ones are determined. 相似文献
320.
Within the framework of the kinetic theory of strength, relations for estimation of durability of thermoplastic materials
under stationary and non-stationary thermomechanical impacts are obtained It is shown that durability decreases linearly with
increase in the natural (Napierian) logarithm of the mean size of microcracks formed during manufacturing of polymer products.
__________
Translated from Izvestiya Vysshikh Uchebnykh Zavedenii, Fizika, No. 7, pp. 3–6, July, 2007. 相似文献