Про рівномірну збіжність одного класу подвійних тригонометричних рядів

We have established sufficient conditions of uniform convergence of the series of the form $\sum\limits_{k,l=1} a_{k,l} \sin kx \sin ly$in the strip:$$$-\infty < x < +\infty$$$,$$$\delta \leqslant y \leqslant 2\pi - \delta$$$($$$\delta$$$is a fixed number,$$$0 < \delta < \pi$$$).Встановлено достатні умови рівномірної збіжності рядів виду$$$\sum\limits_{k,l=1} a_{k,l} \sin kx \sin ly$$$у смузі:$$$-\infty < x < +\infty$$$,$$$\delta \leqslant y \leqslant 2\pi - \delta$$$($$$\delta$$$- фіксоване число,$$$0 < \delta < \pi$$$)

Дослідження з проблеми підсумовування в Дніпропетровському державному університеті

Researches on summation problem in Dnipropetrovsk State University.Дослідження з проблеми підсумовування в Дніпропетровському державному університеті

INTERACTION OF SUPERSONIC TWO-PHASE FLOW GAS+SOLID PARTICLE WITH OBSTACLE AND FORMATION OF SOLID-PHASE COVERS

The processes of interacting supersonic two-phase flow (gas+solid particle) with obstacle surface were investigated for a purpose of determining a possibility to apply the covers for particles in the solid state at temperature of the working gas deceleration near to the room one. The stand of the experimental plants with a possibility to change the flow parameters and, specifically, velocites of the particles within the limits of 200 - 1,200 m/s has been created; the optic systems of the laser diagnostics for determination of the two-phase flow parameters have been created. The data about velocity unequibrium at acceleration of the two-phase flow in the supersonic nozzles have been obtained, the particle resistance coefficient depending on the Mach and Reynolds number has been determined. The value of the critical concentration in the particles (volumetric), difficulty leading to the change of the flow parameters has been specified. At flowing of the bodies, the body resistance decrease effect and also the effect of forming cover on the body surface have been explained, the procedure of the &quot;cold&quot; gasodynamic deposition (CGD) has been proposed. The CGD method bases, properties of the covers and the realization field have been investigated.Available from VNTIC / VNTIC - Scientific & Technical Information Centre of RussiaSIGLERURussian Federatio

Current state of the rearing of replacement young-of-the-year Acipenseriformes in the conditions of the southern Ukraine

Purpose. Examine and analyze the current state of storage fingerlings acipenseriformes cultivation, including sturgeon and paddlefish, in terms of industrial-experimental Dnieper sturgeon fish-growing factory located in the southern Ukraine. Methodology. The problems were solved by the conventional methods in hydrochemistry, hydrobiology and fish farming. The results were processed using statistical methods of the data processing and analysis which suggest it reliable. Findigs. The research has established that physical and chemical parameters of water in farms' ponds answered the operating pond fishery regulations. The existing level of natural forage base elements can be considered satisfacting for the growing storage material. The best development of zooplankton in the application of polyculture acipenseriformes should be noted. The monoculture benefit was observed in the most fisheries indicators for certain types. Sturgeon fish productivity advantage in terms of polyculture is the evidence of positive mutual influences among the reservoir consumers of different trophic levels. In terms of polyculture the significant benefit of total fish productivity indicator was observed. It clearly points to the prospects of the measure in terms of substantial efficiency of pond areas for growing storage fingerlings. Results of acipenseriformes growing in mono- and polyculture clearly favor the polyculture, which could be used in breeding practice. Scientific Originality. In specific conditions of the southern Ukraine the influence of environmental and technological conditions for growing storage fingerlings acipenseriformes fish (sturgeon and paddlefish) was investigated for the first time. In terms of mono- and polyculture cultivation storage acipenseriformes fish material was firstly explored. Practical Value. The results of cultivation can be used in breeding practice as the norm of the environmental situation evaluation in the ponds. Growing storage fingerlings acipenseriformes in polyculture allows better usage of the natural food base, improving productivity and efficient usage of farms' water growing areas

Problem of Casual Walks without Self-Intersections in Physics of Polymers

Available from VNTIC / VNTIC - Scientific & Technical Information Centre of RussiaSIGLERURussian Federatio