Certain methods of optimization of the reception of quantum signals
Certain methods of optimization of the reception of quantum signals
A.G. Vantsyan and R.L. Stratonovich
The question of optimal quantum - signal processing is analyzed. An ideal quasim easurement which improves the quality of the estimation algorithm is introduced. The optimality of one particular algorithm for estimating noncommuting quantities, based on the quasi - measurement is proven for the special quadratic-Gaussian case.
Show AbstractMutual synchronization of coupled relaxation-type generators
Mutual synchronization of coupled relaxation-type generators
V.I. Chernyshev
Mutual synchronization of circuits containing up to five thyratron generators is investigated experimentally and theoretically. The mutual synchronization dom ain, amplitude distributions and the steady period of oscillations in the sync hronization band are calculated for two coupled generators. Comparison with experimental results is made.
Show AbstractDetermination of the natural width of fringe spectral components of the fine structure of the rayleigh light scattering line in N-hexadecane
Determination of the natural width of fringe spectral components of the fine structure of the rayleigh light scattering line in N-hexadecane
G.P. Petrova and N.A. Pichikyan
A rapid Fourier transform algorithm is employed for determining the true contours of components of the Mandel'shtam - Brillouin triplet in hexadecane at 60°C It is shown that in the case when the width of the experimental contour and of the instrument function are close in magnitude, it is possible to calculate the true contour by imposing certain conditions on the spectrum of the sought function.
Show AbstractExperimental investigation of the rough bottom turbulence structure above a rough bottom
Experimental investigation of the rough bottom turbulence structure above a rough bottom
N.K. Shelkovnikov, L.A. Bukina, and P.V. Mironov
The time and space-time correlation functions in a rough-bottom test tank were measured. Eulerian turbulence scales, subsequently used for determining space scales L calculated on the assumption of validity of the Taylor theorem, are obtained from one-point measurements of velocity fluctuations obtained by a hotwire anemometer array. The longitudinal dimensions of turbulent inhomogeneities at two levels were determined from two-point recordings.
Show AbstractModels for describing wall turbulence in viscous fluids
Models for describing wall turbulence in viscous fluids
V.A. Gorodtsov and V.S. Shandin
Various models of a fluctuating viscous sublayer are examined. Conditions for matching the average values for the viscous sublayer and external [free-stream] turbulence make it possible to relate the oscillatory period with characteristics of the fluid and the free-stream turbulence and to describe satisfactorily the average velocity distribution in the vicinity of the wall.
Show AbstractA pyroelectric transducer of turbulent fluctuations
A pyroelectric transducer of turbulent fluctuations
V.K. Novik, Yu.M. Romanovskii, and V.N. Sokolov
A device for measuring turbulent fluctuations in liquids is described. A pyroelectric transducer of TsTS-19 [lead zirconate-titanate] ceramic measures the temperature fluctuations induced by changes in flow velocity. The transducer effectiveness is improved by artificial heating. An elementary calculation Is presented of the output signal for the case of harmonic fluctuations.
Show AbstractOn the existence of four types of acoustic waves in the statistical model of a crystal
On the existence of four types of acoustic waves in the statistical model of a crystal
A.A. Vlasov and N.G. Inozemtseva
It is shown that the statistical model of a crystal allows the existence of various types of acoustic waves. Their physical characteristics are determined; the feasibility of experimental detection of the new wave type is discussed.
Show AbstractParametric properties of subharmonic oscillations
Parametric properties of subharmonic oscillations
A.N. Vakhrameev
The parametric nature of energy supply to subharmonic oscillations and its features are clarified using an example of the excitation of the third subharmonic in anonlinear electric circuit.
Show AbstractConcerning matrix representation of cascade connections of quadripoles
Concerning matrix representation of cascade connections of quadripoles
V.I. Shestakov
Matrix representation of cascade connections of quadripoles, some of the branches of which are open, is impossible, since multiplication of matrices with elements equal to infinity is undefined. The article presents a method of algebraic description of cascade connections of quadripoles which reduce to pairs of bipoles, the impedances of which can have any values, including also infinity as a particular case.
Show AbstractApplication of the root-locus method in the study of absolute stability of nonlinear systems by the Popov criterion
Application of the root-locus method in the study of absolute stability of nonlinear systems by the Popov criterion
G.A. Bendrikov and G.A. Sidorova
The Popov frequency-response stability criterion is written in analytic form in terms of general formulas. The transformed Popov's equation is explored by the root-locus method. The stability is determined from the location of the principal points of the root-locus hodograph as a function of the independent parameters q and k.
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