Test recognition

We describe the logic approach to pattern recognition; its key notion is a test. Analyzing the tests allows us to construct functionals characterizing the pattern, as well as procedures to compute them. We present qualitative and quantitative properties of tests, functionals, and recognition procedures. Solutions of a series of known problems are also given.     

Methods of estimating the angular and energy characteristics of generated laser emission

The physical models used to estimate the angular and energy characteristics of laser emission generated in the kinetic and coherent regime of emission interaction with an active medium are critically analyzed and systematized.Quantum Radiophysics and Optics Division, Lebedev Physics Institute. Translated from Preprint No. 176 of the Lebedev Physics Institute, Academy of Sciences of the USSR, Moscow, 1989.     

Spectral Properties and Photochemical Activity of Chalcone Derivatives

A relationship is found between spectral-luminescent and photochemical properties for mono- and disubstituted chalcone derivatives ^R1CO-CH = CHR² [R¹, R² = Ph, 4-FC₆H₄, 4-BrC₆H₄, 2-furyl, 2-thienyl, 4-(PhCONH)C6H4, 4-NH₂C₆H₄, 4-Me₂NC₆H₄].     

Effect of aluminates on electrochemical characteristics of the aluminum-indium-tin alloy

Electrochemical dissolution of an Al-In-Sn alloy in 2–4 M NaOH solutions containing 0–3 M of sodium aluminate at temperatures of 40 and 75°C was studied by measuring potentiodynamic curves and chronopotentiograms.     

A Study of the Dynamics of Formation of Plasmoids in the Gatchina Discharge

Technical Physics - The results of studies of the Gatchina discharge conducted at the Harbin University of Technology (China) have been presented. The Gatchina discharge is mainly used to create an...     

On the relative role of GCR intensity variations and the Suess’ effect in the data on <Superscript>14</Superscript>C isotope content in tree rings

The relative contribution from GCR intensity variations and anthropogenic carbon dioxide emissions into the atmosphere (the Suess effect) to the variation of ¹⁴C isotope content in annual tree rings is considered. The contribution from a reduction in GCR intensity to the lowering of the cosmogenic ¹⁴C isotope content in tree rings from the middle of the 19th century to the middle of the 20th century is shown to be comparable to the contribution from the Suess effect.     

Determination of the exact solutions to the inhomogeneous burgers equation with the use of the darboux transformation

A method of determining the exact solutions to the Burgers equation on the basis of the Darboux transformation is described. It is shown that a single application of the Darboux transformation to the homogeneous Burgers equation transforms the latter into the inhomogeneous equation describing acoustic wave propagation against transonic flow in the de Laval nozzle. In this case, the contraction ratio of the nozzle is fixed and determined by the viscosity coefficient of the medium. Based on the exact solution of the homogeneous Burgers equation, for the aforementioned problem of the flow in the nozzle, all the possible regular steady-state solutions are presented and the evolution of nonstationary solutions is investigated. The algorithm of a multiple Darboux transformation, which allows an increase in the strength of inhomogeneity, i.e., in the contraction ratio of the nozzle, is determined. This approach leads to a discrete set of possible contraction ratios at which exact solutions can be obtained. The Crum’s theorem is used to derive a formula that allows determination of the exact solutions to the inhomogeneous Burgers equation from the solutions to the homogeneous heat transfer equation. It is noted that, in fact, the proposed algorithm of the multiple Darboux transformation makes it possible to decrease the viscosity coefficient of the medium in a discrete way.     

On the 75th Birthday of Yu.M. Polukarov

Russian Journal of Electrochemistry -     

Hydrogen depth profile measurement in a-Si1-xCx:H films by elastic recoil detection

The hydrogen content and depth profile in a-Si_1-xC_x:H films were measured by the elastic recoil detection (ERD) technique. It is shown that the hydrogen content changes from 15 to 50 at% with increasing carbon content x. For x<0.4 the hydrogen content increases mainly due to the increase of the Si-CH₃ contribution and for x > 0.4 due to C-H bonds. By combining the ERD and IR results, the proportionality between the number of Si-CH₃ bonds and the intensity of IR absorption due to the Si-CH₃ rocking mode vibration is ascertained. The proportionality constant is found to be A^roc_Si-CH3 = 5 × 10¹⁹ cm^-2.