7 research outputs found

    Development of cluster models for municipal educational institutions of Tomsk region

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    This paper describes the cluster models construction for schools in the Tomsk region. K-means method is used to distribute objects between clusters using the multidimensional vector of variables (socio-economic status of students, qualification and age of teaching staff, students' participation in academic competitions, students in difficult living conditions, etc.). The cluster models were constructed for urban schools (regional center), country and ungraded schools. The computer simulation using STATISTICA system was performed due to large amount of source data and complexity of the developed models. The analysis showed the relationship between the values of cluster variables and the results of Unified State Exams (USE)

    Production of intermediate-mass dileptons in relativistic heavy ion collisions

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    The production of intermediate mass dileptons in ultrarelativistic nuclear collisions at SPS energies is studied. The acceptance and detector resolution inherent to measurements by the NA50 experimental collaboration are accurately modeled. The measured centrality dependence of the intermediate mass lepton pair excess is also addressed.Comment: 9 pages, 8 figures, ReVTe

    Large mass dileptons from the passage of jets through quark gluon plasma

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    We calculate the emission of large mass dileptons originating from the annihilation of quark jets passing through quark gluon plasma. Considering central collisions of heavy nuclei at SPS, RHIC and LHC energies, we find that the yield due to the jet-plasma interaction gets progressively larger as the collision energy increases. We find it to be negligible at SPS energies, of the order of the Drell-Yan contribution and much larger than the normal thermal yield at RHIC energies and up to a factor of ten larger than the Drell-Yan contribution at LHC energies. An observation of this new dilepton source would confirm the occurrence of jet-plasma interactions and of conditions suitable for jet-quenching to take place.Comment: 9 pages, 11 figures; references added, improved calculation, conclusions unchange

    Radionuclide contamination of underground water and soils near the epicentral zone of cratering explosion at the Semipalatinsk Test Site

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    The investigation wells for a control of the underground water contamination were bored after the cratering explosions at the Semipalatinsk Test Site, now they are restored partially. The analysis of the retrospective information of the Institute of Global Climate & Ecology (Moscow, Russia) give a possibility to choose wells and terrains for the successful study of radionuclide migration with the underground water. The epicentral zone, the crater and the territory with radius 1,5 km around the explosion “1003" were investigated under the ISTC project K-810. Underground water and soil samples were taken at the two expeditions of 2003. The chemical extraction methods taking into account the water mineral composition, gamma-spectrum methods, methods of liquid scintillation spectrometry and methods of alfa-spectrometry were used. The modern radionuclide content (3H, 90Sr, 137Cs, 239+240Pu, 241Am etc.) of the underground water is presented and compared with a radionuclide content of soils around crater. The retrospective information has been added by these modern data. The vertical radionuclide distrioin soils is presented

    Impacts of environmental change on biodiversity and vegetation dynamics in Siberia

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    Biological diversity is the basis for, and an indicator of biosphere integrity. Together with climate change, its loss is one of the two most important planetary boundaries. A halt in biodiversity loss is one of the UN Sustainable Development Goals. Current changes in biodiversity in the vast landmass of Siberia are at an initial stage of inventory, even though the Siberian environment is experiencing rapid climate change, weather extremes and transformation of land use and management. Biodiversity changes affect traditional land use by Indigenous People and multiple ecosystem services with implications for local and national economies. Here we review and analyse a large number of scientific publications, which are little known outside Russia, and we provide insights into Siberian biodiversity issues for the wider international research community. Case studies are presented on biodiversity changes for insect pests, fish, amphibians and reptiles, birds, mammals and steppe vegetation, and we discuss their causes and consequence

    Principles of spatial organization and evolution of the biosphere and the noosphere

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