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1.
A Volterra type integral equation in a Hilbert space with an additional linear operator L and a spectral parameter depending
on time is considered. If the parameter does not belong to the spectrum of L unconditional solvability of the considered problem
is proved. In the case where the initial value of the parameter coincides with some isolated point of the spectrum of the
operator L sufficient conditions for solvability are established. The obtained results are applied to the partial integral
equations associated with a contact problem of the theory of elasticity. 相似文献
2.
We solve the problem of diffraction of fluctuating radiation by an optically thin irregular layer (phase screen) with developed turbulent structure. It is shown that in the case of diffraction of radiation with saturated fluctuations and a narrow-band frequency spectrum by a weakly turbulent moving phase screen, the measured frequency spectrum of intensity fluctuations in the observation plane allows one to obtain information on the form of the spectrum of irregularities of an optically thin irregular layer in a wide size range significantly exceeding the size of the first Fresnel zone. Similarly to the well-known phase method of diagnostics of randomly irregular media, the conventional scintillation method modified in such a way yields undistorted information on the form of the irregularity spectrum. However, in contrast to the phase method, it also allows one to obtain data on the drift velocity of irregularities in the studied irregular layer. 相似文献
3.
V. A. Alimov 《Radiophysics and Quantum Electronics》1995,38(11):727-730
We compare the computational possibilities of the radio-wave refraction-scattering method (RWRSM) and the parabolic-equation method (PEM) in determining the statistical characteristics of radio waves in a medium with large-scale inhomogeneities. It is shown that on the whole the applicability limits of the RWRSM are similar to the corresponding limits of the PEM. However, unlike the PEM, the RWRSM makes it possible, in a number of cases, to use simple means to solve radio-wave-refraction problems in a thick layer with large-scale inhomogeneities.Radiophysical Research Institute, Nizhny Novgorod. Translated from Izvestiya Vysshikh Uchebnykh Zavedenii, Radiofizika, Vol. 38, No. 11, pp. 1118–1123, November, 1995. 相似文献
4.
Conclusions A number of methylenebis-[N-dialkoxythio(seleno)phosphoryl-N-carbethoxymethylamines] was obtained by the condensation of the N-carbethoxymethylamides of dialkylthio(seleno)phosphoric acids with paraform,Translated from Izvestiya Akademii Nauk SSSR, Seriya Khimicheskaya, No. 11, pp. 2603–2604, November, 1974. 相似文献
5.
6.
D. A. Alimov 《Differential Equations》2018,54(3):392-400
We study the existence and uniqueness of a solution of the Bellman equation formalizing the operation of a manufacturing company under conditions of irregular demand and debt load. The class of functions where this equation has a unique solution is determined. The choice of a specific solution is justified. 相似文献
7.
The effect of low-temperature annealing on the magnetization curve of YBa2Cu3O6 + x ceramics in the superconducting state (x ≈ 0.9) is investigated. When the annealing time is fairly long, the field dependence of magnetic moment M exhibits a feature in the form of a plateau, where the value of M remains almost constant. The evolution of this feature in the magnetization curves of annealed samples with annealing time and temperature is studied. It is assumed that low-temperature annealing gives rise to metastable ferromagnetic clusters in YBa2Cu3O6 + x ceramics, the contribution of which to the magnetic moment accounts for the feature in the magnetization curves of the annealed samples. 相似文献
8.
Marzhan Nassurlla N. Burtebayev T. Kh. Sadykov I. Boztosun N. Amangeldi D. Alimov Zh. Kerimkulov J. Burtebayeva Maulen Nassurlla A. Kurakhmedov S.B. Sakuta Mesut Karakoc Awad A. Ibraheem K.W. Kemper Sh. Hamada 《中国物理C(英文版)》2020,44(10):104103-104103-9
The angular distributions of elastic scattering of 14N ions on 10B targets have been measured at incident beam energies of 21.0 and 24.5 MeV. Angular distributions at higher energies 38–94.0 MeV (previously measured) were also included in the analysis. All data were analyzed within the framework of the optical model and the distorted waves Born approximation method. The observed rise in cross sections at large angles was interpreted as a possible contribution of the α-cluster exchange mechanism. Spectroscopic amplitudes SA2 and SA4 for the configuration 14N→ 10B +α were extracted. Their average values are 0.58±0.10 and 0.81±0.12 for SA2 and SA4, respectively, suggesting that the exchange mechanism is a major component of the elastic scattering for this system. The energy dependence of the depths for the real and imaginary potentials was found. 相似文献
9.
M. M. Alimov 《Fluid Dynamics》2008,43(5):751-762
In experiments on the displacement of viscous fluids in a Hele-Shaw cell of channel type the catastrophic development of competition between fingers is sometimes observed: for a long time two fingers propagate almost side by side and then one of them suddenly suppresses the other. It is believed that this is a manifestation of the capillary forces on the phase interface [1]. Using the solution found in [2] for the problem in an idealized formulation, it is shown that this scenario is perfectly feasible without having to take capillary forces into account. 相似文献
10.
Mathematical Notes - For unbounded subsets E of the complex plane, we obtain conditions that are necessary or sufficient so that, for any compact set K that does not divide the plane, the simple... 相似文献