73 research outputs found
A new book on the history of the Murman coast colonization
The review of the book by P.V. Fedorov and A.A. Malashenkov “Soil on the Northern rocks: Orthodox necropolis of the Murmansk coast of the Barents Sea (1863–1920)”. The study based on the processing of metrical books made it possible to publish the information about 2,524 persons of the Orthodox religion buried on the Murmansk coast, or drowned in the sea in 1863–1920. The Authors found the demographic statistics related to the appearance of the settlements with permanent population. The book clarifies the idea of “cultural soil”, local and family-genealogical structures in the Russian Arctic, and it also contributes to the historical personification of the Murmansk coast
Ceramics based on titanium nitride and silicon nitride sintered by SPS-method
The dependences of the microstructure and physical and mechanical properties of ceramic mixtures Si[3]N[4]/TiN in the full range of mass ratios of the components. Was also investigated directly, and the process of sintering occurring during a physical or chemical processes, in particular, has been obtained and the hardness of the material density on the ratio of the conductive titanium nitride phase and a silicon nitride insulating phase with values above and below the percolation threshold. Also obtained was pure ceramics based on titanium nitride with high physical-mechanical characteristics (H=21.5 GPa)
Bjorken Sum Rule and pQCD frontier on the move
The reasonableness of the use of perturbative QCD notions in the region close
to the scale of hadronization, i.e., below \lesssim 1 \GeV is under study.
First, the interplay between higher orders of pQCD expansion and higher twist
contributions in the analysis of recent Jefferson Lab (JLab) data on the
Generalized Bjorken Sum Rule function at is studied. It is shown that the inclusion of the higher-order
pQCD corrections could be absorbed, with good numerical accuracy, by change of
the normalization of the higher-twist terms. Second, to avoid the issue of
unphysical singularity (Landau pole at Q=\Lambda\sim 400 \MeV ), we deal with
the ghost-free Analytic Perturbation Theory (APT) that recently proved to be an
intriguing candidate for a quantitative description of light quarkonia spectra
within the Bethe-Salpeter approach. The values of the twist coefficients
extracted from the mentioned data by using the APT approach provide
a better convergence of the higher-twist series than with the common pQCD. As
the main result, a good quantitative description of the JLab data down to
350 MeV is achieved.Comment: 10 pages, 3 figures, minor change
Normalizers of maximal tori and real forms of Lie groups
For a complex reductive Lie group Tits defined an extension of
the corresponding Weyl group . The extended group is supplied with an
embedding into the normalizer of the maximal torus such
that together with generate . We give an interpretation of
the Tits classical construction in terms of the maximal split real form
, leading to a simple topological
description of . We also propose a different extension of the
Weyl group associated with the compact real form . This results into a presentation of the normalizer of maximal
torus of the group extension by the
Galois group . We also describe explicitly
the adjoint action of and on the Lie algebra of .Comment: 17 page
On quantization of singular varieties and applications to D-branes
We calculate the ring of differential operators on some singular affine
varieties (intersecting stacks, a point on a singular curve or an orbifold).
Our results support the proposed connection of the ring of differential
operators with geometry of D-branes in (bosonic) string theory. In particular,
the answer does know about the resolution of singularities in accordance with
the string theory predictions.Comment: LaTeX2e, 17 pages, misprints correcte
Let’s groove : Attachment techniques of Eurasian elk (Alces alces) tooth pendants at the Late Mesolithic cemetery Yuzhniy Oleniy Ostrov (Lake Onega, Russia)
More than 4300 Eurasian elk (Alces alces) incisors, most of them pendants, were found in 84 burials in the Late Mesolithic cemetery of Yuzhniy Oleniy Ostrov, Northwest Russia. We analysed the manufacture techniques of elk teeth (4014), in the collection of the Peter the Great Museum of Anthropology and Ethnography, St Petersburg. A striking observation is that the manufacture of these pendants is similar in all burials. Teeth were worked by carving one or several grooves around the root tip. In addition to grooved ones, a number of teeth were not worked at all. The uniformity of the chosen species, tooth and techniques indicates that strict norms prevailed in the pendant industry. Despite the overall similarity, our study shows some variation in making pendants. A groove can cut the whole circumference of the root, or several distinct grooves can mark opposite sides of the root. Sometimes the grooves are deep and made carefully, and sometimes they are weak and made hastily. A typology of various groove types was created. In many graves, one groove type dominates. We interpret that this inter-burial variation and domination of one type resulted from personal choice and taste based on practicality. Such variation could also be associated with kin identifiers, but we did not find clear support for that in our study. Our study indicates that the groove types as such had no connection with particular ornaments, garments or hanging positions.Peer reviewe
Simulation Modeling of Integrated Multi-Carrier Energy Systems
Integrated multi-carrier energy systems give good possibilities to have high effectiveness of energy supply to consumers. Transformation of energy systems under the impact of internal and external factors remarkably strengthens the technological integration of those systems and supports development of integrated multi-carrier energy systems. The concept of energy hub is developed for modeling and simulation of integrated multi-carrier energy systems. Based on previous research, a simulation model of the energy hub is being developed. The basic principles of building a simulation model of an energy hub concept are discussed. Realization of simulation model using Matlab/Simulink is proposed. Simulation results for the integrated electricity and heat systems are explained to demonstrate the capabilities of the simulation energy hub model. A case study for application of the simulation model is discussed
Intensive systematic surveys of palaeospits in the Narva-Luga klint bay area: Analysis of methodology and results
Non peer reviewe
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