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991.
Two groups of 10 speech-language pathology graduate students were each given 7 weeks of singing lessons to determine whether voice lessons could have an effect on their clinical and perceptual skills. Pre-, mid-, and posttests to measure various skills were designed and implemented. With use of paired sample statistical testing, statistically significant results were obtained. In addition, the subjective responses of the students show that the lessons were effective in improving pitch perception, breath control, and legato production or easy onset. This study supports efforts to integrate curricula in vocal performance and speech-language pathology. 相似文献
992.
993.
A. A. Bormisov E. S. Gudkova F. Kh. Mukminov 《Theoretical and Mathematical Physics》1997,113(2):1418-1430
We consider equations of the form Uxy = U * Ux, where U(x, y) is a function taking values in an arbitrary finite-dimensional algebra T over the field ℂ. We show that every
such equation can be naturally associated with two characteristic Lie algebras, Lx and Ly. We define the notion of a ℤ-graded Lie algebraB corresponding to a given equation. We prove that for every equation under consideration, the corresponding algebraB can be taken as a direct sum of the vector spaces Lx and Ly if we define the commutators of the elements from Lx and Ly by means of the zero-curvature relations. Assuming that the algebra T has no left ideals, we classify the equations of the
specified type associated with the finite-dimensional characteristic Lie algebras Lx and Ly. All of these equations are Darboux-integrable.
Translated from Teoreticheskaya i Matematicheskaya Fizika, Vol. 113, No. 2, pp. 261–275, November, 1997. 相似文献
994.
Summary. We study a diffusion model of an interacting particles system with general drift and diffusion coefficients, and electrostatic
inter-particles repulsion. More precisely, the finite particle system is shown to be well defined thanks to recent results
on multivalued stochastic differential equations (see [2]), and then we consider the behaviour of this system when the number
of particles goes to infinity (through the empirical measure process). In the particular case of affine drift and constant diffusion coefficient,
we prove that a limiting measure-valued process exists and is the unique solution of a deterministic PDE. Our treatment of
the convergence problem (as ) is partly similar to that of T. Chan [3] and L.C.G. Rogers - Z. Shi [5], except we consider here a more general case allowing
collisions between particles, which leads to a second-order limiting PDE.
Received: 5 August 1996 / In revised form: 17 October 1996 相似文献
995.
The effect of 57Fe hyperfine interaction radiofrequency (rf) modulation by external rotating magnetic field was studied in thin Permalloy foil by means of Mössbauer spectroscopy. The rf effect was investigated as a function of intensity for several rf field frequencies. The experiments show that the external rotating rf field causes considerable changes in the hyperfine pattern. The obtained spectra are in disagreement with those obtained by Perlow [Phys. Rev. 172 (1968) 319]. They also are inconsistent with magnetostriction hypothesis. Proceeding from the Mössbauer spectrum analysis one may conclude that the magnetization of investigated foil changes its direction in a complex manner. However, the undertaken experiments show that the essential number of Mössbauer nuclei experience the rotating magnetic field influence. 相似文献
996.
997.
S. K. Godovikov 《JETP Letters》1998,68(8):629-633
In research on the production of beams of coherent γ rays (γ-ray lasers), conditions under which a substantial change Δλ/λ=?(0.114 ±0.027) in the radioactive decay constant λ (the isomeric level 89.53 keV 119m Sn, T 1/2=293 days) can occur have been found experimentally for the first time. This is made possible by coherent Mo ssbauer (23.87 keV) backscattering from a resonant screen located nearby. An interpretation of the effect observed is proposed on the basis of the idea of dynamic synchronization of oscillations between a nuclear level and a standing wave of Mössbauer radiation. Possibilities for further increasing Δλ/λ up to 0.5 are found. 相似文献
998.
The dependence of the type of magnetic ordering in multilayer structures on the magnitude of the exchange interaction between
the magnetic layers and on the degree of roughness of the interfaces between the layers is investigated. In the case of a
three-layer system the regions of existence of the domain structure, of noncollinear ordering of the homogeneous magnetic
layers, and of the collinear ferromagnetic phase and collinear antiferromagnetic phase are found.
Fiz. Tverd. Tela (St. Petersburg) 39, 1244–1247 (July 1997) 相似文献
999.
1000.
E. S. Sinaiskii 《Ukrainian Mathematical Journal》1997,49(11):1768-1776
We consider an integral equation describing the contagion phenomenon, in particular, the equation of the state of a hereditarily
elastic body, and interpret this equation as a stochastic model in which the Rabotnov exponent of fractional order plays the
role of density of probability of random delay time. We invesgigate the approximation of the distribution for sums of values
with a given density to the stable distribution law and establish the principal characteristics of the corresponding renewal
process.
Ukrainian Mining Academy, Dnepropetrovsk. Translated from Ukrainskii Matematicheskii Zhurnal, Vol. 49, No. 11, pp. 1572–1579,
November, 1997. 相似文献