Main results of atmospheric fine structure parameter observation in the lower thermosphere

The capabilities of the radiometeor method of wind measurement increase with the increase of the transmitted power of radar stations fitted with goniometric systems which enables the observation of shower meteors along with sporadic background. In shower observations the meteor zone reflecting area narrows to the echo surface which is perpendicular to the flux radiant. Favorable conditions are created for singling out atmospheric disturbances in which the wave front is parallel to the echo surface which plays, in this case, the role of a frequency filter. For the first time this technique allowed wave disturbances with periods of approx. greater than 4 min. to be measured, with about a 99 percent probability of exceeding the level of the turbulence noise, during the Geminid and Perseid showers. Maximum values of such wave disturbance amplitudes were about 15 to 20 m/s, with lifetimes up to 2 hrs

Theoretical and experimental study of high-pressure synthesized B20-type compounds Mn1−x_{1-x}(Co,Rh)x_xGe

The search and exploration of new materials not found in nature is one of modern trends in pure and applied chemistry. In the present work, we report on experimental and \textit{ab initio} density-functional study of the high-pressure-synthesized series of compounds Mn$_{1-x}$(Co,Rh)$_x$Ge. These high-pressure phases remain metastable at normal conditions, therewith they preserve their inherent noncentrosymmetric B20-type structure and chiral magnetism. Of particular interest in these two isovalent systems is the comparative analysis of the effect of $3d$ (Co) and $4d$ (Rh) substitution for Mn, since the $3d$ orbitals are characterized by higher localization and electron interaction than the $4d$ orbitals. The behavior of Mn$_{1-x}$(Co,Rh)$_x$Ge systems is traced as the concentration changes in the range $0 \leq x \leq 1$. We applied a sensitive experimental and theoretical technique which allowed to refine the shape of the temperature dependencies of magnetic susceptibility $\chi(T)$ and thereby provide a new and detailed magnetic phase diagram of Mn$_{1-x}$Co$_x$Ge. It is shown that both systems exhibit a helical magnetic ordering that very strongly depends on the composition $x$. However, the phase diagram of Mn$_{1-x}$Co$_x$Ge differs from that of Mn$_{1-x}$Rh$_x$Ge in that it is characterized by coexistence of two helices in particular regions of concentrations and temperatures.Comment: 12 pages, 11 figure

Simple algorithm of wavelet-compression of halftone and colour images

Simple algorithm of wavelet-compression allowing realizing inexpensive hardware and software platforms for closed circuits and processing systems of high definition television in real time has been develope

Rosenblatt's first theorem and frugality of deep learning

First Rosenblatt's theorem about omnipotence of shallow networks states that elementary perceptrons can solve any classification problem if there are no discrepancies in the training set. Minsky and Papert considered elementary perceptrons with restrictions on the neural inputs: a bounded number of connections or a relatively small diameter of the receptive field for each neuron at the hidden layer. They proved that under these constraints, an elementary perceptron cannot solve some problems, such as the connectivity of input images or the parity of pixels in them. In this note, we demonstrated first Rosenblatt's theorem at work, showed how an elementary perceptron can solve a version of the travel maze problem, and analysed the complexity of that solution. We constructed also a deep network algorithm for the same problem. It is much more efficient. The shallow network uses an exponentially large number of neurons on the hidden layer (Rosenblatt's $A$-elements), whereas for the deep network the second order polynomial complexity is sufficient. We demonstrated that for the same complex problem deep network can be much smaller and reveal a heuristic behind this effect