Strength diagrams of fibrous composites with unidirectional structure

The dependence of the composite strength on the volume proportion of fiber and the transfer factor is analyzed. Four types of diagrams are constructed for the strength of composites as a function of the volume proportion of fibers and the transfer factor

Join Execution Using Fragmented Columnar Indices on GPU and MIC

The paper describes an approach to the parallel natural join execution on computing clusters with GPU and MIC Coprocessors. This approach is based on a decomposition of natural join relational operator using the column indices and domain-interval fragmentation. This decomposition admits parallel executing the resource-intensive relational operators without data transfers. All column index fragments are stored in main memory. To process the join of two relations, each pair of index fragments corresponding to particular domain interval is joined on a separate processor core. Described approach allows efficient parallel query processing for very large databases on modern computing cluster systems with many-core accelerators. A prototype of the DBMS coprocessor system was implemented using this technique. The results of computational experiments for GPU and Xeon Phi are presented. These results confirm the efficiency of proposed approach

On the upper limit of antinuclei content in cosmic rays

Upper limit of antinuclei content in cosmic ray

Mechanisms of the interaction between the labor market and system of professionals’ training in professional educational organization

Проанализированы современные подходы, применяемые в процессе профессиональной подготовки будущих специалистов. Рассмотрены основные элементы механизма взаимодействия рынка труда и системы подготовки специалистов в профессиональной образовательной организации.In the article the modern approaches used in the process of professional training of future specialists are analyzed. It is described the main elements of the mechanism of the interaction between the labor market and system of training in professional educational organizations

Supernova Ia: a Converging Delayed Detonation Wave

A model of a carbon-oxygen (C--O) presupernova core with an initial mass 1.33 M_\odot, an initial carbon mass fraction 0.27, and with an average mass growth-rate 5 x 10^{-7} M_\odot/yr due to accretion in a binary system was evolved from initial central density 10^9 g/cm^3, and temperature 2.05 x 10^8 K through convective core formation and its subsequent expansion to the carbon runaway at the center. The only thermonuclear reaction contained in the equations of evolution and runaway was the carbon burning reaction 12C + 12C with an energy release corresponding to the full transition of carbon and oxygen (with the same rate as carbon) into 56Ni. As a parameter we take \alpha_c - a ratio of a mixing length to the size of the convective zone. In spite of the crude assumptions, we obtained a pattern of the runaway acceptable for the supernova theory with the strong dependence of its duration on \alpha_c. In the variants with large enough values of \alpha_c=4.0 x 10^{-3} and 3.0 x 10^{-3} the fuel combustion occurred from the very beginning as a prompt detonation. In the range of 2.0 x 10^{-3} >= \alpha_c >= 3.0 x 10^{-4} the burning started as a deflagration with excitation of stellar pulsations with growing amplitude. Eventually, the detonation set in, which was activated near the surface layers of the presupernova (with m about 1.33 M_\odot) and penetrated into the star down to the deflagration front. Excitation of model pulsations and formation of a detonation front are described in detail for the variant with \alpha_c=1.0 x 10^{-3}.Comment: 13 pages, 11 figures, to appear in Astronomy Letter

Economic prospects of innovative technologies of in vitro cultivation of seedlings

Purpose: The article discusses the economic prospects of innovative technologies for planting material of forest trees. The results of the development of an organizational model of business processes of growing forest seedlings are given and the stages of reproduction technology are described, its competitive advantages are revealed. Structure/Methodology/Approach: The use of innovative technologies in reforestation and afforestation in Russia remains insufficiently developed. Promising methods of reforestation is the use of seedlings grown by cloning. Findings: The duration and cost for each stage of the forest seedling technology were determined. The technology of clonal micropropagation includes a combination of techniques, the choice of a donor plant and the preparation of the source material of the species. Practical implications: It has been established that the development and introduction of technological innovations into practice requires financial support, due to the high cost of growing seedlings of woody plants. The developed organizational model of the process of clonal micropropagation can be used in organizing the production of seedlings of woody plants in forest seed breeding centers. Originality/Value: The development of clonal breeding technologies for modern breeding and seed centers is promising, however, there are a few difficulties that impede the successful development of production and reduce the economic efficiency ofreforestation activities.peer-reviewe

On the estimate of the sigma^(I = 1)_(KN)(0)-term value from the energy level shift of kaonic hydrogen in the ground state

Using the experimental data on the energy level shift of kaonic hydrogen in the ground state (the DEAR Collaboration, Phys. Rev. Lett. 94, 212302 (2005)) and the theoretical value of the energy level shift, calculated within the phenomenological quantum field theoretic approach to the description of strong low-energy anti-K N and anti-K NN interactions developed at Stefan Meyer Institut fuer subatomare Physik in Vienna, we estimate the value of the sigma^(I = 1)_(KN)(0)-term of low-energy anti-K N scattering. We get sigma^(I = 1)_(KN)(0) = (433 +/- 85) MeV. This testifies the absence of strange quarks in the proton structure.Comment: 7 pages, no figure