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  • Influence of receptor-technological factors on properties of fine-grained loaves of rigid Press

    The article presents a technique for designing and assigning the composition of the molding mixture, which is based on the calculation and experimental approach to determining the composition, taking into account the quality of raw materials used and the requirements for the properties of concrete products produced.

    Keywords: Hard pressed concrete, cement, water content of the mixture, two-factor experiment, rotatable composite simplexummable plan, regression equation of the experiment, quasi-factor analysis

  • Creation and investigation of the simulation model of a dynamic voltage distortion compensator

    Background: The quality of electricity is one of the main problems necessary for the normal functioning of responsible technological processes in which a slight distortion of the supply voltage can lead to a violation of the normal operation of enterprises. There are several solutions to this problem: uninterruptible power systems, fast automatic power reserve technology (FAPR), dynamic voltage distortion compensator (DVDC). The most interesting solution is the application of dynamic voltage distortion. Material and methods: The principles of constructing a dynamic voltage distortion compensator with multilevel voltage inverters are investigated. An imitation model constructed under the following assumptions is proposed: an ideal case of the main circuit system (without higher harmonics) is considered, the nonlinearity of the transformer is not taken into account, short-circuit currents are absent, only constant load power is used. Assumptions are justified by the fact that in practice their error is no more than 3-5%, which is permissible. The results are obtained by modeling the system in the MatLab 2016b package. Results: A fundamentally new structural and functional scheme of a dynamic voltage distortion compensator with a multilevel system is developed. The requirements for the dynamic compensator of voltage distortion, load, LC-filters, current-voltage transformers and a converter are determined. Simulation of the simulation model has shown that the system works and corresponds to the expected results. Conclusions: The proposed voltage compensation system will solve the problem of the normal functioning of technological processes. The simulation results showed that the declared functional of the DVDC provides compensation of the voltage level in a given range of voltage dips. The obtained results can be used to stabilize the power supply: in the power supply systems of medical institutions, electric transport, critical energy facilities of a high category.

    Keywords: Dynamic voltage distortion compensator (DVDC), automatic control system, operation modes of DVDC, model of the DVDC system, multilevel voltage inverter, simulation model, voltage distortion, volt-additional transformer, electric power, voltage failure

  • The method of appointment of the composition of the sand mixture for the manufacture of precast concrete products hard pressing with damping additive

    The paper presents the design procedure and the appointment of the composition of the molding mixtures, which is based on computational-experimental approach to the determination of the composition taking into account the quality of the used raw materials and requirements to the properties of concrete manufactured products

    Keywords: Raw materials, grain structure, concrete, svezheulozhennye mix, precast products, hard pressing, block diagram

  • The growth of sueface layer air temperature from click on the geomagnetic storms

    According to meteorological studies found natural growth of air temperature, coincident in timing with the beginning of a geomagnetic storm. The data were analyzed according to the temperature of about one hundred meteorological stations. Based on this analysis, it was established phenomenon of short-term (30-60 min) growth of surface layer air temperature during the beginning of the magnetic storm, the detected azimuthal drift of the temperature gradient after the start of geomagnetic storms

    Keywords: the low-latitude thermosphere, geomagnetic storm, temperatura air, temperaturny gradient, growth temperature

  • The analysis stage of exploitation and destruction of the normal cross section of the bending of the concrete element

    In article on the basis of the hypothesis of plane cross-sections, non-linear deformation curve of concrete, reinforcement composed and solved equations to describe the stress-strain state of the normal sections of flexible concrete elements at all stages of work and the show features a deformation structure in stages of exploitation and destruction.

    Keywords: Flexible reinforced concrete element, the change in the height of the compressed zone, the levels of the deformation of the reinforcement at failure of the compressed concrete.

  • Experimental investigation on the quality of holes in the multi-layered GFRP-titanium obtained in drilling operations

    The purpose of this work was to study the influence of the structural and geometric parameters of the twist drill on the quality of the processed hole and productivity of machining the high strength polymeric composite material – glass fiber epoxy-based plastics that are reinforced by titanium foil. In the structure of high loaded polymeric composite parts the reinforcing layers made from the titanium foil are used. These titanium layers are placed between layers of the winding unidirectional glass fiber tape or the carbon fiber tape. In order to reach the required dimensional accuracy, the macro- and micro geometry of the hole surfaces, to eliminate the overheat, burning, and delaminations of material, need to use sharp-edged tools, which wear out quickly, and remove the drill from the workpiece at frequent intervals to clean the chips from the flutes of the drill and the hole being drilled. We studied the drilling of glass fiber reinforced laminates at the different schemes of sharpening the drills made from the high-speed steel. We present some experimental results of the optimal feed and speed for the studied twist drills, the dependencies of the highness parameters of roughness, and also characters and degree of delamination at starting and finishing hole for the different tools, feed and cutting speed.

    Keywords: GFRP, drilling GFRP, delaminations, double-angle sharpening

  • Influence of intensive technologies on phenology of development of plants in hothouse combine

    Experimental data about influence of processing in the conditions of hothouse combine on a svetokultura of a cucumber of a grade of "Tseres", research of influence of processing of seeds by rostoregulyator and various modes of the laser on a phytosanitary condition of a cucumber and its productivity are presented in article. Results of researches confirm positive influence of intensive technologies on cucumber plant phenology, on increase of productivity and quality of end products and can be recommended for use in technology in hothouse farms.

    Keywords: огурец, лазер, ростостимулятор, интенсивная технология, фенология, урожайность, качество продукции, исследование, эксперимент.

  • Formation of array nanoparticles during electrodeposition platinum on glassy carbon and dispersed carbon support

    In the present study, platinum was electrodeposited onto rotating disc electrode coated with Vulcan XC-72R Nafion suspension and uncoated smooth glassy carbon electrode from acidic solution of 5mМ H2PtCl6. The electrochemically active surface area of platinum particles obtained was determined by cyclic voltammetry and the structural characteristic of the particles was studied by scanning electron microscopy. The impact of current and time on the electrochemically active surface area of platinum particles electrodeposited on the carbon supports was also investigated and described in this paper. The present work is expected to be utilized and contribute to the improvement of electrochemically active surface area of platinum catalysts for low temperature fuel cells.

    Keywords: galvanostatic electrodeposition, chronopotentiometric curves, chloroplatinic acid, vulcan XC-72R, fuel cells

  • The crack resistance of concrete structures as a function of the marginal elasticity of concrete

    The article considers the problem of determining the moment of cracking in flexible reinforced concrete structures. It is shown that the stress at which cracks, significantly depend on the modulus of elasticity of concrete under tension, equal to the ratio of the elastic part of the deformation to the limit of elasticity of concrete.

    Keywords: diversification of management, production diversification, financial and economic purposes of a diversification, technological purposes of ensuring flexibility of production

  • Nanocomposite organic-hybrid materials

    In this article is reviewed the nature of organic hybrid nanocomposites. Promising directions in the field of organic hybrid nanocomposite materials will be methods for the synthesis of multicomponent materials, as well as the type of "net net" and "host-guest". The fundamental problem with the chemistry and physics of nanocomposites is dependent "structure-property". Solving this problem will move from research materials to their purposeful design.

    Keywords: nanocomposite sol-gel technology, synthesis, nanoparticles.

  • Way of coding of the information at the task of the geometrical Models of executive mechanisms of robots

    The method of coding of the geometrical information is offered at the task of executive mechanisms on the basis of use of the set set of spatial primitive things and their orientation in mobile systems of co-ordinates. The method of a designation of geometrical models of mechanisms of robots is offered. One of advantages of the developed method of representation of geometrical models of kinematic chains, possibility of more exact task of a spatial configuration of manipulators by means of use of a considerable quantity of central points and various position of volume primitive things concerning a constructive plane is.

    Keywords: Mechanisms of manipulators, geometrical models, virtual modelling of movements of robots

  • Acoustic method monitoring electrochemical processes

    The article describes the research of thermodurability of glass-carbon - one of the most promising carbon materials used in the production of luminophors and semiconductor materials, optical single crystals, etc. The aim of this work was to study the behavior glass-carbon in the course of thermo-cyclic testing. As a method of diagnostics of the birth and development of micro-cracks was used by the reception of signals of acoustic emission. It is shown that at heating in the samples glass-carbon there was a strong movement of dislocations in thermocyclic effects ,recognized in the signals of acoustic emission. As the number of pulses when heated above, than during the cooling of the sample, it is evidence of the accumulation of damages in the structure of the cyclic thermal processing glass-carbon samples. It is established, that the curves of the accumulation of defects at the pulses of acoustic emission, differ on the stage of heating and cooling. Proposed to use the curve of the aggregate accounts of acoustic emission pulses as a possible harbinger of destruction when heated glass-carbon of the product.

    Keywords: acoustic emission, electrodeposition, the activity of the AE, the remote control.

  • Diagnosis of the logic element DC LUT FPGA

    In this paper a modification of logic element DC LUT FPGA is proposed for the purpose of the acceleration of diagnostics. Simulation of proposed modification was performed in the system NI Multisim 10 by National Instruments Electronics Workbench Group. Evaluation of hardware costs is also given.

    Keywords: logic element, DC LUT, FPGA, diagnosis, reliability

  • Determination of the atomic structure of bimetallic Pt-Ag nanoparticles in metal-carbon catalysts by X-ray absorption spectroscopy data

    The atomic structure of bimetallic nanoparticles of Pt-Ag composition, which are the part of metal-carbon electro-catalysts PtAg/C, is studied by means of EXAFS spectroscopy using the suggested technique. These materials have been prepared by methods of consistent and simultaneous deposition of Ag and Pt atoms from aqueous ethylene glycol solutions of their salts with subsequent acid treatment. The values ​​of the structural parameters of the near environment of platinum atoms are determined. The nature of the distribution of components in nanoparticles is established. Cluster models of nanoparticles are constructed. The fraction of Pt atoms in the working shell and its dependance on preparation methods in each case are determined.

    Keywords: Metal-carbon electrocatalysts, bimetallic nanoparticles, Catalysis, Platinum, X-ray absorption spectroscopy, atomic structure

  • The methodological bases fuzzy cognitive modelling of hierarchical problem-directed systems

    This article is devoted to description of structure of methodology of modelling of hierarchical problem-directed systems on the example of social and economic systems. In the basis of methodology the principle of a combination of the formalized methods of modelling and expert procedures is put. Modelling of hierarchical system is offered to be spent by means of multilayered fuzzy cognitive maps. Filling of the block of logical-mathematical models in structure of process of decision-making is described in detail. The offered methodology provides the development and choice of well-founded administrative decisions.

    Keywords: Problem-directed system, decision making, fuzzy cognitive model, methodology