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1.
It is shown that equations describing the dynamics of Darwinian systems (DS) far from the bifurcation points may be expressed
in Hamiltonian form. The cases of DS with constant organization and DS with a constant flux through the system are considered.
The configurational part of phase space is formed by variables containing information on the structure of the system. Momentum
variables may be regarded as specific rates of multiplication. The evolution of DS with constant organization in this phase
space is expressed as uniform rectilinear motion. In the case of DS with a constant flux, the motion occurs in some effective
constant and uniform field. The meaning of the elements of the Hamiltonian structure is described in terms of theoretical
biology.
Tomsk State University. Scientific-Research Institute of Biological Systems, Tomsk State University. Translated from Izvestiya
Vysshikh Uchebnykh Zavedenii, Fizika, No. 7, pp. 23–28, July, 1997. 相似文献
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A method is proposed for the formulation of an asymptotic series for the light absorption coefficient in disordered semiconductors with a random field of the Coulomb type. It is shown that the series is obtained by expanding the exponent of an exponential function in powers of a parameter proportional to (Eg–)–1/3, where Eg is the band gap of the semiconductor, and is the photon energy. The first three terms of the series are calculated in explicit form.Translated from Izvestiya Vysshikh Uchebnykh Zavedenii, Fizika, No. 1, pp. 28–32, January, 1988. 相似文献
5.
The kinetics of the formation of sodium chlorate during electrolysis of chloride solutions with use of dimensionally stable anodes is studied. An analysis and calculations suggest that the experimental results are well described by the proposed set of differential equations under the assumption that the homogeneous chemical reaction of chlorate formation has second, rather than third, order by active chlorine. 相似文献
6.
N. N. Veniaminov S. A. Khovavko S. A. Voronov S. L. Orlov L. A. Azarov S. Yu. Arkhipov T. N. Evdokimov 《Journal of Analytical Chemistry》2003,58(4):355-360
The elemental and isotopic composition of the core material of a hard-core projectile that had fallen onto the ground was studied by secondary-ion mass spectrometry, alpha and gamma spectrometry, X-ray photoelectron spectroscopy, and scanning electron microscopy with X-ray microanalysis. The environmental aspect of the use of depleted uranium ammunition in Yugoslavia is discussed. 相似文献
7.
Numerical simulation of traveling wave excitation, propagation, and diffraction in structures with local inhomogeneities (obstacles) is computationally expensive due to the need for mesh-based approximation of extended domains with the rigorous account for the radiation conditions at infinity. Therefore, hybrid numerical-analytic approaches are being developed based on the conjugation of a numerical solution in a local vicinity of the obstacle and/or source with an explicit analytic representation in the remaining semi-infinite external domain. However, in standard finite-element software, such a coupling with the external field, moreover, in the case of multimode expansion, is generally not provided. This work proposes a hybrid computational scheme that allows realization of such a conjugation using a standard software. The latter is used to construct a set of numerical solutions used as the basis for the sought solution in the local internal domain. The unknown expansion coefficients on this basis and on normal modes in the semi-infinite external domain are then determined from the conditions of displacement and stress continuity at the boundary between the two domains. We describe the implementation of this approach in the scalar and vector cases. To evaluate the reliability of the results and the efficiency of the algorithm, we compare it with a semianalytic solution to the problem of traveling wave diffraction by a horizontal obstacle, as well as with a finite-element solution obtained for a limited domain artificially restricted using absorbing boundaries. As an example, we consider the incidence of a fundamental antisymmetric Lamb wave onto surface and partially submerged elastic obstacles. It is noted that the proposed hybrid scheme can also be used to determine the eigenfrequencies and eigenforms of resonance scattering, as well as the characteristics of traveling waves in embedded waveguides. 相似文献
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S. P. Denisov V. N. Evdokimov A. V. Kozelova N. N. Prokopenko M. M. Soldatov D. A. Stoyanova V. I. Yakimchuk 《Bulletin of the Lebedev Physics Institute》2010,37(4):104-110
The Cherenkov counter for measuring the numbers of protons in bunches extracted from the IHEP accelerator using a slow extraction
system is described. The measurement range is from 1 to 106 particle/bunch. The maximum bunch frequency is 6 · 106 s–1. Cherenkov light is measured by an XP 2020 photomultiplier. The results of measurements of the XP 2020 signal amplitude on
the applied voltage, obtained using semiconductor light sources are presented. The data of counter calibration on the proton
beam are discussed. 相似文献