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941.
N. V. Zorii 《Ukrainian Mathematical Journal》1990,42(4):438-443
For a condenser E in an open set D R
p
, p 3, the problem of the minimum of the Green energy in a class of charges, associated with E, is solved.Translated from Ukrainskii Matematicheskii Zhurnal, Vol. 42, No. 4, pp. 494–500, April, 1990. 相似文献
942.
V. P. Yakovets 《Ukrainian Mathematical Journal》1990,42(11):1403-1409
Asymptotic expansions with respect to a small parameter e are constructed for a fundamental system of solutions of a linear singularity perturbed system of equations of the form
相似文献
943.
I. V. Savenkov 《Fluid Dynamics》1990,25(1):151-154
The excitation of instability of the boundary layer on a curved surface in the limit R (R is the Reynolds number) is analyzed.Translated from Izvestiya Akademii Nauk SSSR, Mekhanika Zhidkosti i Gaza, No. 1, pp. 176–179, January–February, 1990.I am grateful to O. S. Ryzhov for his interest in the work. 相似文献
944.
Behavior on the real line of entire functions represented by Dirichlet series with complex exponents
It is shown, in particular, that if n k when n k, Re n > 0, and
, then an entire function F that is bounded on the real line and represented by a Dirichlet series
dn exp (nz) that is uniformly and absolutely convergent on each compactum in is identically zero.Translated from Ukrainskii Matematicheskii Zhurnal, Vol. 42, No. 7, pp. 882–888, July, 1990. 相似文献
945.
V. G. Chernov 《Ukrainian Mathematical Journal》1990,42(3):331-336
We study the algebra of functions on the set of natural numbers with respect to the generalized convolution, generated by the generalized translation operator Tnf(k)=f(max (n, k)), n, k. With the help of the generalized Fourier transform, connected with this convolution, we establish numerous identities and recurrence relations, connecting, in particular, sums of powers of natural numbers.Translated from Ukrainskii Matematicheskii Zhurnal, Vol. 42, No. 3, pp. 372–377, March, 1990. 相似文献
946.
Total backward electron yields from 27 elemental, non-crystalline, clean solids were measured during bombardment by H+-, H-, H-, He+- and Ar+-ions in the energy range from 100 keV to 800 keV. The yields were found to exhibit an oscillatory dependence on the atomic number of the target material correlated with the periods of the periodic system. These Z2-oscillations are relatively insensitive to the type of projectile and the impact energy at the high projectile energies of this experiment. Present theories of electron emission cannot explain the main experimental results. The reasons for this failure are discussed. 相似文献
947.
Analysis, synthesis, and perception of voice quality variations among female and male talkers 总被引:19,自引:0,他引:19
Voice quality variations include a set of voicing sound source modifications ranging from laryngealized to normal to breathy phonation. Analysis of reiterant imitations of two sentences by ten female and six male talkers has shown that the potential acoustic cues to this type of voice quality variation include: (1) increases to the relative amplitude of the fundamental frequency component as open quotient increases; (2) increases to the amount of aspiration noise that replaces higher frequency harmonics as the arytenoids become more separated; (3) increases to lower formant bandwidths; and (4) introduction of extra pole zeros in the vocal-tract transfer function associated with tracheal coupling. Perceptual validation of the relative importance of these cues for signaling a breathy voice quality has been accomplished using a new voicing source model for synthesis of more natural male and female voices. The new formant synthesizer, KLSYN88, is fully documented here. Results of the perception study indicate that, contrary to previous research which emphasizes the importance of increased amplitude of the fundamental component, aspiration noise is perceptually most important. Without its presence, increases to the fundamental component may induce the sensation of nasality in a high-pitched voice. Further results of the acoustic analysis include the observations that: (1) over the course of a sentence, the acoustic manifestations of breathiness vary considerably--tending to increase for unstressed syllables, in utterance-final syllables, and at the margins of voiceless consonants; (2) on average, females are more breathy than males, but there are very large differences between subjects within each gender; (3) many utterances appear to end in a "breathy-laryngealized" type of vibration; and (4) diplophonic irregularities in the timing of glottal periods occur frequently, especially at the end of an utterance. Diplophonia and other deviations from perfect periodicity may be important aspects of naturalness in synthesis. 相似文献
948.
A. V. Zorin 《Russian Physics Journal》1990,33(5):441-443
A general form of chronological ordering is proposed, based on introduction of relativistically invariant multipoint step functions (x1, ..., xn). A system of recursive relations is established for these functions, which guarantees that the scattering matrix is unitary, covariant, and causal. The explicit form of the first four -functions is found. A comparative analysis of the known methods of chronological ordering is given.Translated from Izvestiya Vysshikh Uchebnykh Zavedenii, Fizika, No. 5, pp. 70–73, May, 1990. 相似文献
949.
The behavior of effective charges i(t) corresponding to the parameters of nonminimal coupling of scalar and gravitational fields in E6 Grand Unification Theory (GUT) in curve spacetimes is studied. It is shown that in a strong gravitational field ¦i(t)¦ grows indefinitely.Translated from Izvestiya Vysshikh Uchebnykh Zavedenii, Fizika, No. 9, pp. 74–11, September, 1990. 相似文献
950.
The simplest gauge theory of an elastic-plastic medium is considered in this paper that takes account of just translational plasticity. The equations of motion for such a model turn out to be linear and permit the normal modes spectrum of a medium to be obtained. Taking account of plasticity results in a cardinal transformation of the elastic branches of the spectrum and the appearance of a group of plasma oscillations of a dislocation gas.Translated from Izvestiya Vysshikh Uchebnykh Zavedenii, Fizika, No. 6, pp. 64–68, June, 1990. 相似文献
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