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21.
The Wheeler–DeWitt equation of arbitrary Hartle–Hawking factor ordering for several minisuperspace universe models, such as the pure gravity Friedmann–Robertson–Walker and Taub ones, is mapped onto the dynamics of corresponding classical oscillators. The latter ones are studied by the classical Ermakov invariant method, which is a natural approach in this context. For the more realistic case of a minimally coupled massive scalar field, one can study, within the same type of approach, the corresponding squeezing features as a possible means of describing cosmological evolution. Finally, we comment on the analogy with the accelerator physics. 相似文献
22.
A.-S. F. Obada M. Darwish H. H. Salah 《International Journal of Theoretical Physics》2002,41(9):1755-1768
In this paper a new state called odd-excited binomial state (OEBS) is introduced. It interpolates between the odd number state and the odd-excited coherent state. We discuss some statistical properties, such as the Glauber second-order correlation function and squeezing phenomenon (normal and amplitude-squared squeezing) for this state. The quasiprobability distribution functions (Husimi Q-function and Wigner W-function) are also examined. 相似文献
23.
A. L. Apanasenko A. V. Kuznichenko Yu. B. Govyadovskii V. G. Yakunin 《Journal of Applied Spectroscopy》1991,54(3):271-276
Translated from Zhurnal Prikladnoi Spektroskopii, Vol. 54, No. 3, pp. 438–444, March, 1991. 相似文献
24.
Yu. K. Voron'ko A. B. Kudryavtsev V. V. Osiko E. V. Sorokin 《Journal of Applied Spectroscopy》1991,55(4):953-957
Translated from Zhurnal Prikladnoi Spektroskopii, Vol. 55, No. 4, pp. 535–540, October, 1991. 相似文献
25.
26.
B. P. Harlamov 《Journal of Mathematical Sciences》2006,133(3):1371-1377
An inverse process with independent positive increments is considered. For such a process, the first hitting time τx of level x as a function of x ≥ 0 is a proper process with independent positive increments. In terms of first hitting times
and their Levy measures, multidemensional distribution densities and Laplace transformations are derived. Stationary distributions
of increments of the process are investigated. Bibliography: 8 titles.
__________
Translated from Zapiski Nauchnykh Seminarov POMI, Vol. 311, 2004, pp. 286–297. 相似文献
27.
M. A. H. Dempster 《Journal of Mathematical Sciences》2006,133(4):1422-1444
This paper gives a comprehensive treatment of EVPI-based sequential importance sampling algorithms for dynamic (multistage)
stochastic programming problems. Both theory and computational algorithms are discussed. Under general assumptions it is shown
that both an expected value of perfect information (EVPI) process and the corresponding marginal EVPI process (the supremum
norm of the conditional expectation of its generalized derivative) are nonanticipative nonnegative supermartingales. These
processes are used as importance criteria in the class of sampling algorithms treated in the paper. When their values are
negligible at a node of the current sample problem scenario tree, scenarios descending from the node are replaced by a single
scenario at the next iteration. On the other hand, high values lead to increasing the number of scenarios descending from
the node. Both the small sample and asymptotic properties of the sample problem estimates arising from the algorithms are
established, and the former are evaluated numerically in the context of a financial planning problem. Finally, current and
future research is described. Bibliography: 49 titles.
__________
Published in Zapiski Nauchnykh Seminarov POMI, Vol. 312, 2004, pp. 94–129. 相似文献
28.
29.
A. R. Volkov B. V. Shul'gin T. I. Polupanova V. N. Lebedev A. A. Nagornyi V. L. Petrov Yu. F. Kargin 《Journal of Applied Spectroscopy》1991,54(6):585-590
Translated from Zhurnal Prikladnoi Spektroskopii, Vol. 54, No. 6, pp. 970–975, June, 1991. 相似文献
30.