Wavelet-function formation in the problem of music signal identification

Approach allowing forming wavelet-functions on the basis of periodic signals and signal fragments of musical instruments has been suggested. The required and sufficient conditions made to the formed wavelet-functions were considered. The experiment allowing identifying some harmonic components of a signal localized in time was described. The possibility of applying the developed approach in the tasks of identifying complex musical signals was show

Scalar field in a minimally coupled brane world: no-hair and other no-go theorems

In the brane-world framework, we consider static, spherically symmetric configurations of a scalar field with the Lagrangian (\d\phi)^2/2 - V(\phi), confined on the brane. We use the 4D Einstein equations on the brane obtained by Shiromizu et al., containing the usual stress tensor T\mN, the tensor \Pi\mN, quadratic in T\mN, and E\mN describing interaction with the bulk. For models under study, the tensor \Pi\mN has zero divergence, so we can consider a "minimally coupled" brane with E\mN = 0, whose 4D gravity is decoupled from the bulk geometry. Assuming E\mN =0, we try to extend to brane worlds some theorems valid for scalar fields in general relativity (GR). Thus, the list of possible global causal structures in all models under consideration is shown to be the same as is known for vacuum with a $Lambda$ term in GR: Minkowski, Schwarzschild, (A)dS and Schwarzschild-(A)dS. A no-hair theorem, saying that, given a potential $V\geq 0$, asymptotically flat black holes cannot have nontrivial external scalar fields, is proved under certain restrictions. Some objects, forbidden in GR, are allowed on the brane, e.g, traversable wormholes supported by a scalar field, but only at the expense of enormous matter densities in the strong field region.Comment: 8 pages, Latex2e. Numerical estimates and a few references adde

OPTIMIZATION OF BURNING PRODUCTION PROCESS OF CERAMSITE WITH SPECIFIED DENSITY

The paper goes into peculiarities of using developed mathematical models of ceramsite burning and computational models created on their basis. The work is done in the light of analysis and synthesis of multivariate control system of kiln angular velocity and kiln charge with volumetric thermal capacity burners. It is shown that computational models of burning as an object of control are problem-oriented on producing ceramsite with specified density. Mathematical model of ceramsite burning process as an object with distributed parameters is synthesized. The transition from model with distributed parameters to the mode with lumped parameters is performed. Then the authors used a model with three bearing cross-sections along Z-axis in Matlab software and created a computational model of multivariate object of control with inter-channel connections. The paper presents experimental computational set up methods and methods of ceramsite burning optimal curve identification on the criterion of minimizing energy consumption for burning. The developed method of staging computational experiments makes it possible to predict the strength of ceramsite if values of control actions are known. The results of modeling help create methodology of choosing optimal modes of ceramsite burning with the required mark of strength and with minimum energy consumption

Control for the parameters of a low-pressure glow discharge in argon by means of acoustic flows

© 2017, Pleiades Publishing, Ltd. The possibility to control the parameters of a low-pressure glow discharge in argon by means acoustic flows is demonstrated by numerical simulations. It is shown that such flows result in an increase in the densities of charged and excited particles in the axial region of the discharge and contraction of the positive column, while stability of the discharge is preserved

Asymptotic Infrared Fractal Structure of the Propagator for a Charged Fermion

It is well known that the long-range nature of the Coulomb interaction makes the definition of asymptotic ``in'' and ``out'' states of charged particles problematic in quantum field theory. In particular, the notion of a simple particle pole in the vacuum charged particle propagator is untenable and should be replaced by a more complicated branch cut structure describing an electron interacting with a possibly infinite number of soft photons. Previous work suggests a Dirac propagator raised to a fractional power dependent upon the fine structure constant, however the exponent has not been calculated in a unique gauge invariant manner. It has even been suggested that the fractal ``anomalous dimension'' can be removed by a gauge transformation. Here, a gauge invariant non-perturbative calculation will be discussed yielding an unambiguous fractional exponent. The closely analogous case of soft graviton exponents is also briefly explored.Comment: Updated with a corrected sign error, longer discussion of fractal dimension, and more reference

Transverse acoustic oscillations in cylindrical chambers with the radial temperature gradient

In this article the transverse acoustic oscillations in cylindrical chambers with a radial temperature gradient are considered. Expression for the velocity potential is calculated. This expression describes the free transverse oscillations in cylindrical chamber with radial temperature gradient

The model of the positive column of a glow discharge with the influence of the acoustic oscillations

© Published under licence by IOP Publishing Ltd. In article the model of the positive column of a glow discharge with the influence of acoustic waves is developed. It is shown that the radial convective flow caused by the acoustic streaming leads to a redistribution of the gas temperature, and reduces its gradient between the axis and the wall of the discharge chamber

Some numerical simulation results of the dynamic temperature distribution in dc plasma torch Thermoplasma 50-01

© Published under licence by IOP Publishing Ltd. A DC plasma torch "Thermoplasma 50-01" has been modeled and simulated by developing a 2D axisymmetric model of laminar flow and heat transfer coupled to electromagnetic fields. As a result of the numerical solution, the dynamics of the formation of the temperature field and the velocity field in the plasma torch channel and at its exit is presented. The numerical results of the gas temperature and axial velocity result to be quite satisfactory

Multitemporal generalization of the Tangherlini solution

The n-time generalization of the Tangherlini solution [1] is considered. The equations of geodesics for the metric are integrated. For $n = 2$ it is shown that the naked singularity is absent only for two sets of parameters, corresponding to the trivial extensions of the Tangherlini solution. The motion of a relativistic particle in the multitemporal background is considered. This motion is governed by the gravitational mass tensor. Some generalizations of the solution, including the multitemporal analogue of the Myers-Perry charged black hole solution, are obtained.Comment: 14 pages. RGA-CSVR-005/9