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Highly filled biocomposites may be used as biodegradable masterbatches that manufacturers add to traditional polymers for making plastic goods more biodegradable. Biocomposites based on various trademarks of ethylene-vinyl acetate copolymer (EVA) and natural vegetable fillers (wood flour and microcrystalline cellulose) were studied. The EVA trademarks differed both in terms of the melt flow index and in the content of vinyl acetate groups. The composites were created as superconcentrates (or masterbatches) for the production of biodegradable materials based on vegetable fillers with polyolefin matrices. The filler content in biocomposites was 50, 60, 70 wt.%. The influence of the content of vinyl acetate in the copolymer and its melt flow index on the physico-mechanical and rheological properties of highly filled biocomposites was evaluated. As a result, one EVA trademark with high molecular weight that has a high content of VA was chosen because of its optimal parameters for creating highly filled composites with natural fillers.

The study is devoted to measurements of heat flux with an external high speed gas flow around the axisymmetric model. Sensors based on bismuth anisotropic thermoelements were used. Experiments were carried out using Big Shock Tube. The models used for experiments were the combinations of a cone with an opening angle of 60 degrees and a cylinder. The models with heat flux sensors were placed in the outer section of the flat supersonic nozzle. The results were compared with theoretical estimates made using the effective length method. The data obtained demonstrate the applicability of sensors in gas-dynamic experiments with test times about 1 ms., Представлены результаты измерения теплового потока с помощью датчиков на анизотропных термоэлементах при внешнем обтекании модели высокоскоростным потоком аргона. Эксперименты выполнены на большой ударной трубе ФТИ им. Иоффе. Обтекаемые модели представляли собой комбинацию конуса с углом раскрытия 60 градусов и цилиндра и устанавливались в рабочей камере, отделенной от ударной трубы тонкой диафрагмой, закрывающей вход в плоское сверхзвуковое сопло, находящееся в рабочей камере. Модели с тепловыми датчиками на основе анизотропных термоэлементов из висмута размещались в выходном сечении сопла. Сравнение экспериментальных результатов с теоретическими оценками теплового потока, выполненными на основе метода эффективной длины, демонстрирует корректность используемой методики обработки электрического сигнала датчиков на анизотропных термоэлементах и их перспективность в качестве диагностического средства для измерений тепловых потоков при обтекании моделей.

The results of calculating the temperature field and electric potential in the sensitive element of the sensor based on a layered metal structure of a pair of chromel-alumel and copper-nickel in a stationary thermal regime are presented. The influence of the effective thermal conductivity of the structure on the temperature distribution and the generated thermoelectric power is shown. The possibility of using a one-dimensional model for describing thermal and thermoelectric processes in the sensitive element of the sensor is considered., Представлены результаты расчета поля температуры и электрического потенциала в чувствительном элементе датчика на основе слоистой металлической структуры из пары хромель-алюмель и медь-никель в стационарном тепловом режиме. Показано влияние эффективной теплопроводности структуры на распределение температуры и генерируемую термоэдс. Рассмотрена возможность применения одномерной модели для описания тепловых и термоэлектрических процессов в чувствительном элементе датчика.

A discrete analysis of the phase and dissipation errors of an explicit, semi-Lagrangian spectral element method is performed. The semi-Lagrangian method advects the Lagrange interpolant according the Lagrangian form of the transport equations and uses a least-square fit to correct the update for interface constraints of neighbouring elements. By assuming a monomial representation instead of the Lagrange form, a discrete version of the algorithm on a single element is derived. The resulting algebraic system lends itself to both a Modified Equation analysis and an eigenvalue analysis. The Modified Equation analysis, which Taylor expands the stencil at a single space location and time instance, shows that the semi-Lagrangian method is consistent with the PDE form of the transport equation in the limit that the element size goes to zero. The leading order truncation term of the Modified Equation is of the order of the degree of the interpolant which is consistent with numerical tests reported in the literature. The dispersion relations show that the method is negligibly dispersive, as is common for semi-Lagrangian methods. An eigenvalue analysis shows that the semi-Lagrangian method with a nodal Chebyshev interpolant is stable for a Courant-Friedrichs-Lewy condition based on the minimum collocation node spacing within an element that is greater than unity.

Статья посвящена решению актуальной проблемы, связанной с оценкой степени влияния основных социально-экономических показателей на выбор городов областного подчинения и районов Волгоградской области, где целесообразно размещение сети распределительно-подсортировочных складов. На основании двухэтапного кластерного анализа были определены показатели, оказывающие существенное влияние на месторасположение региональной складской сети. Использование дискриминантного анализа позволило количественно оценить влияние социально-экономических показателей на выбор мест расположения складов и с высокой вероятностью определить районы, где возможно формирование региональной складской сети.

We study relations in the Grothendieck ring of varieties which connect the Hilbert scheme of points on a cubic hypersurface $Y$ with a certain moduli space of twisted cubic curves on $Y$. These relations are generalizations of the "beautiful" $Y$-$F(Y)$ relation by Galkin and Shinder which connects $Y$ with the Hilbert scheme of two points on $Y$ and the Fano variety $F(Y)$ of lines on $Y$. We concentrate mostly on the case of cubic surfaces. The symmetries of $27$ lines on a smooth cubic surface give a lot of restrictions on possible forms of the relations.

One of the factors that has a significant impact on the socio-economic development of the Russian Federation’s regions is the logistics infrastructure. It provides integrated transportation and distribution service of material flows. One of the main elements of logistics infrastructure is a storage infrastructure, which includes distribution center, distribution-and-sortout and sortout warehouses. It is the most expedient to place distribution center in the vicinity of the regional center. One of the tasks of the distribution network creation within the regions of the Russian Federation is to determine the location, capacity and number of stores. When determining regional network location of general purpose warehouses methodological approaches to solving the problems of location of production and non-production can be used which depend on various economic factors. The mathematical models for solving relevant problems are the deployment models. However, the existing models focus on the dimensionless power storage. The purpose of the given work is to develop a model to determine the optimal location of general-purpose warehouses on the Russian Federation area. At the first stage of the work, the authors assess the main economic indicators influencing the choice of the location of general purpose warehouses. An algorithm for solving the first stage, based on ABC, discriminant and cluster analysis were proposed by the authors in earlier papers. At the second stage the specific locations of general purpose warehouses and their power is chosen to provide the cost minimization for the construction and subsequent maintenance of warehouses and transportation heterogeneous products. In order to solve this problem the authors developed a mathematical model that takes into account the possibility of delivery in heterogeneous goods from suppliers and manufacturers in the distribution and storage sorting with specified set of capacities. The model allows determining the capacity and location of the home network of warehouses in the Russian Federation regions based on the minimization of the total costs associated with the delivery of goods from suppliers / manufacturers to the warehouse and from the warehouse to customers, material handling products, and annual operating costs for the maintenance of the core network of warehouses.

статья посвящена проблемам повсеместного распространения и популяризации эффективных авторских методик подготовки среди профессорско-преподавательского состава, школьников, студентов и абитуриентов, а также их родителей. Предназначена как для среди профессорско-преподавательского состава, так и для школьников, студентов и абитуриентов, а также их родителей.

The authors believe that development of wear resistant coating compositions basedon W Bis an important task aimed at improvement of durability of working parts of2 2machines. X-ray analysis of coating composition W B – FeCr – FeV is presented in the2 2article. The results of chemical and X-ray analyses of the coating composition comprisingW B – FeCr – 10 % FeV demonstrate that, when the weld metal formed, W Bpartially2 5 2 5dissociates to form borides, vanadium, iron, and chromium. High iron content in thesolid solution causes reduction of its hardness and wear resistance. A 20 % increase in the tungsten boride content leads to formation of elongated grains in the matrix of ironborides, vanadium and chromium borides. A composition containing 4 % of W Bhas a2 5fine-grained structure, and it is characterized by the absence of FeB in the weld metal,and its absence means lower brittleness. In the metal, carbon borides are formed to assure its high hardness. In the matrix, a significant amount of vanadium and chromium is dissolved to help improve its hardness. The study shows that the composition containing40 % of W Bhas a fine-grained structure, and it is characterized by the absence of FeB2 5in the weld metal. Therefore, the coating layer demonstrates the highest resistance toabrasion.Исследована структура наплавленного металла на основе W B. С использованием рентгентгенофазового анализа установлено, что при содержании в сплаве 40 % W B соединение Fe с B не образуется.

The article is devoted to an actual problem of integration interaction of educational institutions of various levels. The concepts of integration and pedagogical interaction are analyzed; the features and the intrinsic characteristics which are showing in modern conditions of a development of education are marked out in this article. The question of mechanisms of realization of integration interaction is designated there. The distance interactive courses devoted to development of innovative models of education are offered as one of the possible mechanisms of realization of integration interaction of pedagogical higher education institution and establishments of the general education. The development of innovative models of education is considered in two directions: on the one hand, the role of pedagogical higher education institution in the spread of innovations and rendering the methodical help to teachers in their development is allocated; on the other hand, the way of integration interaction, in particular, the use of Moodle environment and Adobe Connect system, can be considered as innovative. Possibilities of Moodle ("Modular object-oriented dynamic learning environment") as environments of distance learning which is intended for development and placement of training and methodical materials in the Internet/the Intranet network and the organization of educational process on their basis, and also Adobe Connect as flexible system of the distributed training and communication with use of technologies of the web communications, allowing to provide a possibility of teaching, training and collaboration at any distance on the Internet are characterized in the article. The feature of the research is design and realization of distance learning on the basis of a Moodle environment and Adobe Connect system combination in online modes and offline, use of interactive models of occupations. The results of research received during training of teachers at distance advanced training courses on development of innovative models of education in the conditions of implementation of Federal State Educational Standards, National Educational Projects and Initiatives are described in the article.

The article is devoted to the analysis of railway safety management system. It is clear that advanced railway safety management system is of great importance for a country. The fact is understandable as well as for the global community due to rail transport is a part of the logistics chain, which facilitates international trade and economic growth. In the article the author also examines the key components of safety management system and the requirements to it. Safety is regarded by the author of the article as a prime consideration in the successful performance of duties of railway managers. Management is specifically responsible for the development and implementation of safe practices and procedures. It is pointed out that the objectives of the safety management system regulations are to ensure that safety is given management time and corporate resources and that it is subject to performance measurement and monitoring on par with corporate financial and production goals. The author of the article stresses that it is important to railway safety management system that company policy should sustain continuing programs designed to promote the health and safety of all employees and to co-operate with organizations and associations devoted to safety research and education. Russia has 85,000km of railways, making it the second largest network in the world after the US. Rail dominates the freight transport network accounting for 42.7% of total turnover, according to the Federal State Statistics Service, and around 85% of total turnover, if pipeline traffic is not included. Rail has a competitive advantage due to the large distances between different production centers in Russia. The road network is currently insufficient in terms of coverage and quality of the roads, while the waterways freeze during Russia’s long winter. The major cargo types carried by rail are coal (23% of the total) followed by oil products, (18%) and construction materials, (15%). That’s way railway safety management system is very important to RZD as to a railway company of any other country.

The article deals with the method of distortions compensation in digital synthesizers of frequencies with help of which the effective realization of undistorted signal modulation at synthesizer's output is possible are considered

This paper reports the preliminary results of two test pit excavations in Toplitsa cave in Northern Bulgaria and discusses the potential for future investigations of the Pleistocene layers associated with Marine Isotope Stage 3 and the transitional Middle to Upper Palaeolithic period. We describe the lithostratigraphic layers, archaeological finds and features attributable to the Upper Palaeolithic. The preliminary chrono-cultural interpretation of the early Upper Palaeolithic geoarchaeological deposit at Toplitsa cave is based on the identification of Campanian Ignimbrite/Y-5 (CI) tephra, radiocarbon dates and the technological assessment of a small lithic artefact assemblage in comparison with the regional Initial Upper Palaeolithic (IUP) technologies. Toplitsa cave, located in the Eastern Balkans (Northern Bulgaria), was excavated in 2011 with the main goal of investigating deposits encompassing the transition from the Middle to Upper Palaeolithic. Two test pits (TP) were excavated: TP I, incorporating four lithostratigraphic layers, was located in the cave interior and TP II, encompassing six lithostratigraphic layers, was established closer to the cave entrance. Both TPs were generally poor in archaeological remains which impacted the chrono-cultural attribution of the Pleistocene layers. Moreover, in some spots Holocene faunal remains likely intruded into older layers. In consequence, the preliminary chronological investigation has been focused on applying both tephrochronology and radiocarbon dating of the early Upper Palaeolithic deposits. We present a preliminary assessment of the stratigraphy and report on the identification of large amounts of glass shards belonging to the CI eruption (ca. 39,000 years old (ka BP)) in TP II Layers 2 and 3, below which there is a well preserved hearth. This fire-pit carved in Layer 5 (TP II) and underlying the Y-5 tephra is the most significant find. Two Ursus spelaeus teeth from the underlying Layer 5 have been radiocarbon dated to 49,770–45,750 calibrated years before present (cal BP; 95.4% probability) and to 48,210–45,050 cal BP (95.4% probability). The lithics found in Layer 5 are technologically consistent with the Initial Upper Palaeolithic (IUP) or possibly with other transitional Middle to Upper Palaeolithic assemblages. Layer 5 from TP II in Toplitsa overlaps chronologically with other regional records. These include the final Middle Palaeolithic with leaf points from Musselievo (estimated to ca. 50–45 ka cal BP), the transitional Middle to Upper Palaeolithic assemblage from Temnata Cave Layer VI (trench II, which is covered by CI tephra and has been dated to older than 39 ka BP), the earliest laminar Upper Palaeolithic (i.e. IUP) from Temnata Cave Layer 4 (trench I, dating from 47.6 to 40.5 ka cal BP), the IUP from Bacho Kiro Cave Layers J and I (dating to 46.0–43.3 ka cal BP) and Kozarnika cave Layer 6/7 (dated to ca. 49.1–44.0 ka cal BP).