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31.
We present an adaptive method to extract shape-preserving information from a univariate data sample. The behavior of the signal is obtained by interpolating at adaptively selected few data points by a linear combination of multiquadrics with variable scaling parameters. On the theoretical side, we give a sufficient condition for existence of the scaled multiquadric interpolant. On the practical side, we give various examples to show the applicability of the method.  相似文献   
32.
In Fayers and Martin [J. Algebra 240 (2001), 859–873], the author and Martin constructed embeddings of Schur algebras S(2,r)↪S(2,R). Here, we generalise to the q-Schur algebras Sq(2,r). Presented by A. Verschoren Mathematics Subject Classifications (2000) 20G05, 20C33.  相似文献   
33.
用Alhassid与Levine所提出的动力学李代数的方法(简称A-L理论),研究了含有二级非简谐的共线散射体系A+BC的平-振能量传递问题,计算了散射过程含有主要动力学参量的跃迁矩阵和跃迁几率的解析表示式.  相似文献   
34.
We find a minimal system of generators and a homogeneous system of parameters for the algebra of invariants of three matrices of third order over a field of an arbitrary characteristic.  相似文献   
35.
Complexes of adenine, AdH, with cobalt, nickel and copper chlorides were prepared and their thermodynamic functions were determined. The complexing processes are endothermic in nature. The thermal behaviour of complexes was followed up by using TG and DTA analyses. The stoichiometry of thermal decomposition of the investigated complexes was suggested. This revised version was published online in August 2006 with corrections to the Cover Date.  相似文献   
36.
The sterically stabilized emulsion polymerization of styrene initiated by a water‐soluble initiator at different temperatures has been investigated. The rate of polymerization (Rp) versus conversion curve shows the two non‐stationary‐rate intervals typical for the polymerization proceeding under non‐stationary‐state conditions. The shape of the Rp versus conversion curve results from two opposite effects—the increased number of particles and the decreased monomer concentration at reaction loci as the polymerization advances. At elevated temperatures the monomer emulsion equilibrates to a two‐phase or three‐phase system. The upper phase is transparent (monomer), and the lower one is blue colored, typical for microemulsion. After stirring such a multiphase system and initiation of polymerization, the initial coarse polymer emulsion was formed. The average size of monomer/polymer particles strongly decreased up to about 40% conversion and then leveled off. The initial large particles are assumed to be highly monomer‐swollen particles formed by the heteroagglomeration of unstable polymer particles and monomer droplets. The size of the “highly monomer” swollen particles continuously decreases with conversion, and they merge with the growing particles at about 40–50% conversion. The monomer droplets and/or large highly monomer‐swollen polymer particles also serve as a reservoir of monomer and emulsifier. The continuous release of nonionic (hydrophobic) emulsifier from the monomer phase increases the colloidal stability of primary particles and the number of polymer particles, that is, the particle nucleation is shifted to the higher conversion region. Variations of the square and cube of the mean droplet radius with aging time indicate that neither the coalescence nor the Ostwald ripening is the main driving force for the droplet instability. © 2003 Wiley Periodicals, Inc. J Polym Sci Part A: Polym Chem 41: 804–820, 2003  相似文献   
37.
In this paper, we examine the sensitivity of trust-region algorithms on the parameters related to the step acceptance and update of the trust region. We show, in the context of unconstrained programming, that the numerical efficiency of these algorithms can easily be improved by choosing appropriate parameters. Recommended ranges of values for these parameters are exhibited on the basis of extensive numerical tests. MSC classification: 65K05, 90C26, 90C30  相似文献   
38.
Let R be a local ring and let (x 1, …, x r) be part of a system of parameters of a finitely generated R-module M, where r < dimR M. We will show that if (y 1, …, y r) is part of a reducing system of parameters of M with (y 1, …, y r) M = (x 1, …, x r) M then (x 1, …, x r) is already reducing. Moreover, there is such a part of a reducing system of parameters of M iff for all primes P ε Supp MV R(x 1, …, x r) with dimR R/P = dimR M − r the localization M P of M at P is an r-dimensional Cohen-Macaulay module over R P. Furthermore, we will show that M is a Cohen-Macaulay module iff y d is a non zero divisor on M/(y 1, …, y d−1) M, where (y 1, …, y d) is a reducing system of parameters of M (d:= dimR M).  相似文献   
39.
A multiparameter boundary-value problem of fresh infiltration water seepage in a drained fringe above quiescent saline water is solved in the direct statement and studied in detail.  相似文献   
40.
本文得到了正定Hermitian阵的Hadamard积的Schur补的一些不等式,进而,给出了他们的一些应用,这些改进了近期的一些结束.  相似文献   
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