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971.
Design theory crosses the boundary between mathematics and statistics, and includes a wide range of disparate types of design. In this paper we present a classification scheme which aims to include as many important types as possible, based on a balance among concept, representation and use. 相似文献
972.
C. Adamuscin A.-Z. Dubnicková S. Dubnicka R. Pekárik P. Weisenpacher 《The European Physical Journal C - Particles and Fields》2003,28(1):115-118
A system of linear homogeneous algebraic equations for the coupling constant ratios of vector mesons to hadrons is derived
by imposing the assumed asymptotic behavior upon the VMD pole parameterization of an hadron electromagnetic form factor. A
similar system of equations with a simpler structure of the coefficients, taken as even powers of the vector-meson masses,
is derived by means of integral superconvergent sum rules for the imaginary part of the considered form factor using its
appropriate -function approximation. Although both systems have been derived starting from different properties of the electromagnetic
form factor and they each have their own appearances, it is shown explicitly that they are fully equivalent.
Received: 20 March 2002 / Revised version: 3 December 2002 / Published online: 7 March 2003 相似文献
973.
974.
A. Heidenreich I. Schek D. Scharf J. Jortner 《Zeitschrift für Physik D Atoms, Molecules and Clusters》1991,20(1):227-229
The time resolved dynamics of diffusionless cube → ring isomerization of the Na4Cl4 cluster was interrogated by constant energy molecular dynamics simulations, utilizing the first passage time method. The nonreactive isomerization induced by nonselective vibrational excitation is well accounted for in terms of the statistical RRK theory, opening avenues for experimental exploration of time-resolved cluster isomerization dynamics. 相似文献
975.
976.
A. B. Vasil’eva 《Ukrainian Mathematical Journal》2007,59(3):396-408
We present results from the theory of singular perturbations and, in particular, from a new branch of this theory (contrast
alternating-type structures).
__________
Translated from Ukrains’kyi Matematychnyi Zhurnal, Vol. 59, No. 3, pp. 359–369, March, 2007. 相似文献
977.
A. Yu. Kolesov E. F. Mishchenko N. Kh. Rozov 《Proceedings of the Steklov Institute of Mathematics》2007,259(1):101-127
We carry out a detailed analysis of the existence, asymptotics, and stability problems for periodic solutions that bifurcate
from the zero equilibrium state in systems with large delay. The account is based on a specific meaningful example given by
a certain scalar nonlinear second-order differential-difference equation that is a mathematical model of a single-circuit
RCL oscillator with delay in a feedback loop. 相似文献
978.
Athanassios G. Bratsos 《Numerical Algorithms》2007,46(1):45-58
A predictor–corrector (P-C) scheme is applied successfully to a nonlinear method arising from the use of rational approximants
to the matrix-exponential term in a three-time level recurrence relation. The resulting nonlinear finite-difference scheme,
which is analyzed for local truncation error and stability, is solved using a P-C scheme, in which the predictor and the corrector
are explicit schemes of order 2. This scheme is accelerated by using a modification (MPC) in which the already evaluated values
are used for the corrector. The behaviour of the P-C/MPC schemes is tested numerically on the Boussinesq equation already
known from the bibliography free of boundary conditions. The numerical results are derived for both the bad and the good Boussinesq
equation and conclusions from the relevant known results are derived.
相似文献
979.
Bernhard G. Bodmann Vern I. Paulsen Soha A. Abdulbaki 《Journal of Fourier Analysis and Applications》2007,13(3):285-307
We study the performance of finite frames for the encoding of vectors by applying standard higher-order sigma-delta quantization
to the frame coefficients. Our results are valid for any quantizer with accuracy ε > 0 operating in the no-overload regime.
The frames under consideration are obtained from regular sampling of a path in a Hilbert space. In order to achieve error
bounds that are comparable to results on higher-order sigma-delta for the quantization of oversampled bandlimited functions,
we construct frame paths that terminate smoothly in the zero vector, that is, with an appropriate number of vanishing derivatives
at the endpoint. 相似文献
980.
Yu. K. Dem’yanovich 《Journal of Mathematical Sciences》2007,144(6):4548-4567
On a sequence of embedded nonuniform grids, chains of embedded spaces of minimal splines (not necessarily polynomial) are
constructed. The wavelet decomposition is given. The basis wavelets are compactly supported and admit simple analytic representation.
The corresponding decomposition and reconstruction formulas are derived. The variety of spaces under consideration is identified
with the variety of complete sequences of points of the direct product of an interval and a projective plane. Bibliography:
20 titles.
__________
Translated from Problemy Matematicheskogo Analiza, No. 35, 2007, pp. 15–31 相似文献