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911.
Vsevolod K. Malinovskii 《Acta Appl Math》1994,34(1-2):261-281
Edgeworth expansions for the distribution of a sequential least squares estimator in the random coefficient autoregressive (RCA) model are derived. The regenerative approach to second-order asymptotic analysis of Markov-type statistical models is developed. 相似文献
912.
I.L. Lyubchanskii N.N. Dadoenkova M.I. Lyubchanskii E.A. Shapovalov A.E. Zabolotin K.Y. Guslienko T. Rasing 《Applied physics. B, Lasers and optics》2002,74(7-8):711-714
Nonlinear (at the second-harmonic frequency of the incident light) optical reflection by two-dimensional magnetic superstructures
is theoretically studied. A square lattice of magnetic dots and a hexagonal lattice of magnetic bubbles (cylindrical magnetic
domains) are considered. Because the periods of these structures are comparable with the wavelengths of the fundamental and
the second-harmonic radiation, it would be possible to observe diffraction at the second-harmonic frequency. A polarization
analysis of nonlinearly diffracted radiation is performed and the numbers of observable diffraction orders for the above structures
are estimated.
Received: 10 January 2002 / Published online: 11 June 2002 相似文献
913.
Hadroprduction ofJ/ψ in π? nucleus collisions is studied in the context of the colour singlet model using nuclear structure functions from three different models of the EMC effect. We conclude that it is possible to understand the data on the large transverse momentum (p T ) and small Feynmanx (x F ) of theJ/ψ in terms of the nuclear dependence of structure functions alone. We further show that these data can be used to distinguish between different models of the EMC effect, and that a study of distributions in various kinematic variables in photoproduction ofJ/ψ should be able to very effectively supplement the information obtained from hadroproduction experiments. 相似文献
914.
A cluster mechanism is considered for the detachment of particles when the surface of a high-temperature superconducting target
absorbs laser pulses. By proposing a fractal nature for the surface, one can model it as an assembly of a large number of
nonlinear oscillators (clusters). Utilizing the method of sudden perturbations, a calculation was made of the probability
of dissociation of these oscillators, i.e., of the detachment of clusters from the surface. The calculated probability decreases
rapidly as the power density of the laser radiation is reduced to some limiting value. This is in agreement with experiments.
State Institute of Sensory Microelectronics. Siberian Branch of the Russian Academy of Sciences. Translated from Izvestiya
Vysshikh Uchebnykh Zavedenii, Fizika, No. 6, pp. 73–77, June, 1997. 相似文献
915.
We construct polynomial orthonormal bases in various function spaces. Our bases have linear order of growth of degrees of
polynomials. We show that this order is optimal. 相似文献
916.
Exact cylindrically symmetric solutions are obtained for a class of interacting scalar and vector fields in a rotating Godel Universe. We select those with the properties of solitons with smooth decrease of the fields to asymptotics and those with sharp boundaries (droplets). It is shown that only some of the droplets are stable with respect to perturbations that preserve cylindrical symmetry.Translated from Izvestiya Vysshikh Uchebnykh Zavedenii, Fizika, No. 5, pp. 24–27, May, 1991. 相似文献
917.
Magnetization measurements in the (Dy
x
Y1−x
)Fe2 intermetallic compounds show evidence of blocking of domain wall motion. This effect is a function of concentrationx. The direction of magnetization is also dependent on the Dy concentration. We have used the Mossbauer spectroscopy of57Fe to verify the direction of magnetization in the series as a function ofx and temperature. The results show that this change in easy direction occurs at higher temperatures than those where the blocking
is detected through DC magnetization measurements.
supported by RHAE/SCT. 相似文献
918.
V. G. Artjuschenko K. I. Kalaidjian M. M. Mirakian 《International Journal of Infrared and Millimeter Waves》1991,12(10):1175-1185
The results of the efficiency of low-mode excitation of a parallel-plate hollow metallic waveguides (HMW) as a function of beam and waveguide parameters are represented. Coupling of two waveguides is also discussed. 相似文献
919.
920.
The asymptotic null distribution of the likelihood ratio test for two cases of ordered hypotheses in a particular genetic model is considered. A simple iterative process is proposed in order to get the restricted estimates. It is shown that both tests have asymptotically a chi-bar squared distribution and the same size. A simulation study is also conducted in order to compare the usual unrestricted test with the corresponding one of ordered hypotheses. Finally, the results are extended to some special cases. 相似文献