Using Rounding Function in the Problems of Finite-Element Analysis

This work offers to supplement polynomial elements used by the step function of Heaviside and rounding functions which allows to simplify and formalise the record of test piecewise continuous function applying it for continual problems solution by the method of Galerkin.Key words: Finite element method; Galerkin; Rounding functio

Elite opinion and foreign policy in post-communist Russia

Russian elite opinion on matters of foreign policy may be classified as ‘Liberal Westerniser’, ‘Pragmatic Nationalist’ and ‘Fundamentalist Nationalist’, terms that reflect longstanding debates about the country’s relationship with the outside world. An analysis of press statements and election manifestoes together with a programme of elite interviews between 2004 and 2006 suggests a clustering of opinion on a series of strategic issues. Liberal Westernisers seek the closest possible relationship with Europe, and favour eventual membership of the EU and NATO. Pragmatic Nationalists are more inclined to favour practical co-operation, and do not assume an identity of values or interests with the Western countries. Fundamentalist Nationalists place more emphasis on the other former Soviet republics, and on Asia as much as Europe, and see the West as a threat to Russian values as well as to its state interests. Each of these positions, in turn, draws on an identifiable set of domestic constituencies: Liberal Westernisers on the promarket political parties, Pragmatic Nationalists on the presidential administration and defence and security ministries, and Fundamentalist Nationalists on the Orthodox Church and Communists

Безопасное тестирование симуляции систем с отказами и разрушением

The paper deals with conformance testing based on formal specications. The con- cept of safe testing was earlier proposed by the authors for trace based conformance. This concept is propagated on the case of (weak) simulation based on a relation between specication and implementation states. The theory of safe simulation of systems with refusals and destructions is proposed. The problems of complete testing and sucient conditions for the existense of complete test suite are discussed. The practical algo- rithm of complete testing for restricted classes of specications and implementations is described.Статья посвящена тестированию соответствия (конформности) реализации требованиям спецификации. Идея безопасного тестирования предложена авторами для конформности, основанной на трассах наблюдений. Эта идея распространяется на случай (слабой) симуляции, основанной на соответствии состояний реализации и спецификации. Предлагается теория безопасной симуляции для систем с отказами и разрушением. Обсуждаются вопросы полноты тестирования и достаточные условия существования полного набора тестов. Предлагается алгоритм полного тестирования для практического применения, опирающийся на некоторые ограничения на реализацию и спецификацию

Generation of Hydrocarbons by Hydrothermal Transformation of Organic Matter of Domanik Rocks

© 2016, Springer Science+Business Media New York.The distinctive properties of products of hydrothermal transformations of organic matter of bituminous rocks from Upper Devonian Domanik carbonate-argillaceous deposits of the Romashkino field, which were formed due to generation of bituminous components present in the rock in free state as well as of hydrocarbons and high-molecular heteroatomic compounds in the insoluble kerogen degradation process, are determined. It is shown that, among the n-alkanes, homologs with even number of carbon atoms dominate in the kerogen degradation products and that the asphaltenes contain two solid disperse phases differing in aromaticity, heteroatom, microelement and vanadium porphyry complex contents, free radical concentration, and solubility in organic solvents. The sequence of leaching out of hydrocarbons, heteroatomic compounds, resins, and asphaltenes from the rock by vapor-gas mixture is studied. The migration and adsorption capacity of n-alkanes with even and odd numbers of carbon atoms is shown to be diverse. Changes in the microstructure of Domanik rocks upon hydrothermal transformations are studied

Compact Source of Electron Beam for Facility of Electron-Beam Welding with the Location of the Electron Gun and the Source of High Voltage in a Single Monoblock. Concept and Bench Tests of the Monoblok Prototype

Представлен прототип компактного источника электронного пучка для установок электронно-лучевой сварки с расположением электронной пушки и источника высоковольтного напряжения в едином моноблоке. Размещение электронной пушки, источника высоковольтного напряжения, электроники управления пучком и питания накала катода источника электронного пучка для электронно-лучевой сварки в едином корпусе-моноблоке снижает вес и стоимость (за счёт уменьшения количества используемых материалов), объём и занимаемые производственные площади. Это существенно расширяет возможности применения представляемого типа источников электронного пучка в разнообразных областях деятельности человека, в том числе в космических технологиях в открытом пространстве космоса. Цель работы – показать целесообразность концепции компоновки источника электронного пучка в едином корпусе-моноблоке на примере стендовых испытаний прототипа источника-моноблока. Спроектирован и изготовлен прототип источника-моноблока. Проведены его предварительные стендовые испытания с лазерным подогревом катода. Обсуждаются возможные применения. Получен электронный ток источника до 70 мА с энергией 90 кэВ. Данный результат демонстрирует возможность практической реализации нового способа компоновки источника электронного пучкаA prototype of an electron beam compact source for electron-beam welding is presented. The electron gun and a high-voltage source are united in a single monoblock. The placement of the electron gun, the high-voltage source, the beam control electronics and the power supply of the cathode heating of the electron beam source for electron beam welding in a single monoblock housing reduces weight and cost by reducing the amount of materials used, volume and occupied production areas. This significantly expands the possibilities of using the presented type of electron beam sources in various fields of human activity, including space technologies in the open space of space. The purpose of the work is to show the expediency of the concept of arranging the electron beam source in the single monoblock housing as the example of bench tests of the source prototype. The prototype of the monoblock was designed and manufactured. Its preliminary bench tests with laser cathode heating were carried out. Its possible applications are discussed. An electron source current up to 70 mA with an energy of 90 keV was obtained. The result obtained demonstrates the possibility of practical implementation of a new method of arranging an electron beam sourc

Safe simulation testing of systems with refusals and destructions

The paper deals with conformance testing based on formal specications. The con- cept of safe testing was earlier proposed by the authors for trace based conformance. This concept is propagated on the case of (weak) simulation based on a relation between specication and implementation states. The theory of safe simulation of systems with refusals and destructions is proposed. The problems of complete testing and sucient conditions for the existense of complete test suite are discussed. The practical algo- rithm of complete testing for restricted classes of specications and implementations is described

MODELLING THE PROCESSES OF HYGROTHERMAL MECHANICS IN RICE DRYING

Grain-crops are justly considered to be the staple food in Russia as well as all over the world. The specific feature is that postharvest processing of the grain and, above all, drying is an essential stage of providing products of high quality in the sufficient amount. The changes of the technological parameters of the drying process which take place over time, have a significant practical value in terms of monitoring the process and defining the modes providing the quality of the product as well as calculating energy demands necessary to carry out this process. Hereof, the quality of the product received is defined by minimum crack formation of rice grain after the process. The aim of the work is to get a mathematical model of hygrothermal mechanics of rice drying. On the basis of A.V. Lykov’s system of differential equations which describe the changes in moisture content, temperature and pressure, transition to the system of ordinary differential equations was offered which is based on drawing up balance of mass and heat during the process of drying. This approach does not consider the properties of moisture content and temperature within the material but takes into account their mean value. Using a simplified model of hygrothermal mechanics of rice drying that we have got enabled us to reproduce the process of drying in the conditions of minimum crack formation within the studied range (the temperature of the drying agent from 50 to 70 °C, speed from 2.3 to 2.8 м/sеk). The dependences we have got enable us to predict the quality of rice grain during drying

Two-dimensional model of material flow in a screw channel with a fixed cover

Features of the viscous-plastic material flow through the screw channel are studied. A promising direction in this case is the transport models determined by the hydrodynamics of the phase transition. The author also analyzed the effect of dimensions on the flow rate of a viscous-plastic material. The material situated in the channel of the rotating auger and bounded by the fixed body will start to move in a translational motion along the channel due to the shear deformation that appears in it, this is where a forced flow appears. The main parameters that determine the volume flow rate are the depth and width of the channel, the diameter of the screw and the frequency of its rotation. A necessary condition for the existence of this flow is the persistence of shear stress in the material, which is possible only if the material has a certain viscosity. The condition of the return flow is the excessive pressure created by the resistance of the head. We assume the case when in these conditions the auger does not move. Then, under the action of pressure from the side of the head, the material will flow from it along the screw channel – in the opposite direction. The volume flow rate of the counter-flow also depends on the depth of the channel, on the diameter and length of the screw, on the viscosity of the material and on the pressure in the head. In practice, however, there is never a countercurrent in the auger channel, and the head pressure exerts a kind of limitation on the direct flow, which is theoretically viewed as a countercurrent, and the productivity of the screw supercharger is the total flow of the two flows. To account for the geometry of the channel, the author developed a mathematical model of the velocity head in a rectangular channel. The resulting equation makes it possible to determine the shear stress in terms of the shear rate of the material. Taking into account the symmetry and linearity of the velocity distribution in the channel with respect to its midpoint, an equation is obtained for the distribution of the shear rate along the height. The dependence, obtained as a result of the analytical solution of the two-dimensional Poisson equation, makes it possible to simplify considerably the calculation of the discharge-pressure characteristics of the extruder part of the screw presses for pressing vegetable oils with respect to the required screw rotation speed