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  • The definition of crisp dominating tactics for development of alternative control decisions in the conditions of total uncertainty

    The article is devoted to modelling of process of decision-making in difficult systems in the conditions of total uncertainty. The problem is formulated on the basis of synthesis of concepts of the control theory and decision-making, the theory of fuzzy sets and the fuzzy logic, the theory of hierarchical multilevel systems, the utility theory and the theory of games. The given concept expands possibilities of the account uncertainty the various nature, typical to mathematical description of the surrounding validity. Problems of search of decisions in an fuzzy hierarchical control system are designated. The way of the description and finding of alternative decisions in multilevel difficult systems is offered in given article. The algorithm is based on information processing in the form of fuzzy intervals taking into account two kinds the politician conservative and aggressive on the basis of criteria «maxmin» and «minmax». The method of projection on individual interval is used for comparison of the fuzzy intervals presented on various dimension scales. The example showing work of algorithm of a choice of two groups of alternatives is resulted: optimistic and pessimistic on a level of hierarchies of the purposes in the conditions of total uncertainty.

    Keywords: Difficult system; decision making, fuzzy interval, the control decision; total uncertainty

  • Simulation of the converter devices transformer in Simulink

    The analysis of electromagnetic processes of thyristor controlled voltage regulator consisting of triple-wound transformer with thyristor units is possible only by means of computer modeling. The synthesis of triple-wound transformer  by means of block diagram method is concerned here. As a platform for modeling use visual simulation package Simulink. Key assumptions in the development of nonlinear mathematical model of the transformer are generally accepted.

    Keywords: three-phase transformer, thyristor voltage regulator, simulation, Simulink

  • Application of binary structure in optimal filters for sequences of pulsed signals

    Application features of dynamic memory devices based on binary fiber-optic structures are researched in optimal filters of sequence of pulse signals.
    The possibility of significant improvement of signal-to-noise ratio in optimal filters of sequence of pulse signals using non-recirculating binary structures compared to recirculators is proved.
    Application of the technical solution based on the method of enhancing identity copies in binary fiber-optic structures allows to achieves the gain in signal-to-noise ratio of about 37 dB for 4096 copies processed, this corresponds to the gain of 22 dB compared to typical recirculator.

    Keywords: binary fiber-optic structure, optimal filter, pulse sequence, signal-to-noise ratio

  • Modeling of changes of physicochemical characteristics of potash fertilizers at storage and transportation

    A model system was designed and test  trials of physical and mechanical characteristics of small – crystalline and granular flotation potassium chloride are studied. This model system allows to design storage and transportation  of fertilizers in bulk in railway wagons and it has the same static and vibrational load as real system. The effect of temperature and relative humidity of the air on hygroscopy of small – crystalline and granular КСl were studied. Furthermore the influence of static load, and time length  of compression process of fertilizing layer and parameters of static and vibrational load on composition of КСl granules were investigated. It was experimentally proved that the humidity increase (0,5 %) of granular КСl and the  increase of static load and time length  of compression process of product during transportation in bulk lead to increase of compaction degree and caking ability of product. Research of the influence of high static load (10-30 kg/sm2) and time length of compression process of fertilizing layer on caking ability and degree of compaction show that small – grained KCl has smaller degree of compaction and considerably higher value of caking ability in comparison with granular KCl.

    Keywords: Potash fertilizers, storage and transportation, hygroscopy, caking ability, degree of compaction, commodity characteristics of fertilizers

  • Nonferroelectric ceramic of La2-xSrxNiO4 with colossal permittivity

    By self-propagating high-temperature synthesis (SHTS) prepared fine powder оf La2-xSrxNiO4 composition , which is used to obtain dense ceramics exhibiting the properties of n-type semiconductor. Prolonged annealing of the samples resulted in a decrease of the conductivity on the order of 3-4, and the changing nature of the dielectric spectrum: dielectric constant ε' has a stable value of 4·104 Hz in the range of 0,4 − 1·105 Hz .

    Keywords: dielectric constant, phase separation, nikelate of strontium lanthanum, self-extending high-temperature synthesis

  • Developing a model for calculation of the stress-strain states in semiconductor structures due to laser processing

    A model is presented for the calculation of thermoelastic stress and displacement  in semiconductor structures
    due to laser processing. Developed software based on the model allows to determine the optimal parameters of laser processing with taking into account the physical and topological parameters of the structure. The model is divided into two tasks: the non-stationary heat  conduction equation is solved, and the equilibrium equations and Hooke's law. For equations solution was used the finite difference method.

    Keywords: Laser processing, thermal stress, finite difference method

  • Modeling of three-level vertical marketing system

    An original mathematical model describing different activities of actors in the vertical marketing system is presented. They are a provider, a agent, a trading enterprise are presented as a controlling subjects. The model is based on the game-theoretical and hierarchical approach. An equilibrium of Germeyer G1 game in terms of sustainable development is established. The method of impulsion is used as a method of hierarchical control to solve this model. The main system operation laws based on numerical experiments are presented.

    Keywords: game theory, hierarchical, three-level control system, method of impulsion

  • Spatial organization grouping signals in associative processes of artificial neural networks

    The article discusses issues related to the development of the optimal structure of neural networks. One of the major problems in the synthesis neural conrollers is ensuring optimal number of neurons and connections between layers  in the network. Necessary to achieve a compromise between the representational network capabilities, and memory that will be required to store it. The article presents a number of heuristics, allowing to reach such a compromise by limiting the number of connections for each neuron.
    This is done through the introduction of two characteristics for the neuron: the radius of the coverage and density of connections. Coverage radius determines the number of neurons that could potentially have a connection to this neuron, and the density of the compound gives the actual number of such compounds. Altogether, these characteristics determine the amount of synaptic connections, which can have a neuron. The article presents the heuristics that allow to define these characteristics depending on the network structure.  

    Keywords: neural network, neural controller, associative memory, machine learning, optimization

  • Mathematical model of straining of orthotropic conical shells

    The article presents a mathematical model of deformation of thin-walled conical shells, considering orthotropic material, geometric nonlinearity and transverse shear. Showing geometric relationships, physical relationships, the functional of total energy of deformation and boundary conditions.

    Keywords: conical shell, tapered panel, mathematical model, geometric nonlinearity, orthotropic, lateral shifts

  • Analysis of the causes of water pollution of Taganrog Bay with oil products

    The article discusses the possible causes of pollution of Taganrog Bay of the Azov Sea with oil products for the period 2008-2013. The key factors of pollution were highlighted. Effects of navigation for cotion was evaluated by navigation intensity. Effect of wastewater was evaluated by the number of oil products which fall from municipal drains and wastewater from industrial plants. The data processing of the federal statistical reporting on the influence of the main contamination factors was carried out.

    Keywords: oil products, water pollution, average annual concentrations

  • The modeling of distribution of felling area in conditions of territorial inconsistency of timber consumers.

    This paper presents mathematic model of optimization of expenses of stock-piling of timber and logging timber from felling areas to timber consumers by transport networks. This model optimize technological processes which appears during the process of stock-piling of timber and logging timber. 

    Keywords: log truck, rail transportation in timber processing complex.

  • Model of dynamic management of a laser beam and a blood-groove on the basis of a biological feed-back

    The method of laser therapy is based on synchronization of phases of inflow (anacrotism) and outflow of blood (catacrotism) in the field of the pathological center with phases of a being narrowed and extending laser spot on a projection of this pathological center. It is supposed that being narrowed on a projection of the pathological center the spot of laser light stimulates blood inflow to the spot center, and the extending spot of a laser beam – activates blood outflow in the direction from the spot center to its periphery. The developed technique of the automated correction of hemodynamic frustration consists in pilot signal formation (in charge of the power and laser positioning) for the laser machine on the basis of a difference between a reference rheogram and a rheogram of the patient (a body site) in real time.The offered technique has to allow to use more efficiently methods of laser therapy at treatment of violations of a blood-groove. The technique is calculated on the basis of numerical experiment by means of methods of mathematical model operation.In the real experiment the question of synchronization of the reference and measured signal is considered solved though this task represents a subject of separate researches.The received pilot signal can be in real time transformed to the current signal operating positioning and laser power.The method gives the chance of an operating control of a condition of the patient and blood-groove diagnostics to, in time and after a session of laser therapy. Development provides possibility of adaptive individual correction and optimization of parameters of influence during a session and a course of treatment.

    Keywords: laser, therapy, technique, rheogram, diagnostics, blood-groove, management, signal

  • Nonstoichiometry and electrochromism of oxides and polyalkaline tungsten bronzes

    Nonstoichiometric tungsten oxides WO3–x and oxide alkaline tungsten bronzes have been studied because of their potential applications in electrochromic devices such as solar panel arrays and “smart windows”. Different phases of 
    WO3–x have been considered. In this part we present results of our research which clearly show that all Magneli phases of tungsten oxides  WOx (namely W40O118, W20O58, W5O14, W18O49, W8O23, W3O8) and oxide tungsten bronzes MxMyWO3 at M-Li, Na, K, Rb, Cs. They are characterized by metal – like properties. Their band structures display an energy gap in the valence band just below the Fermi level.
    We present results of our electrochemical synthesis of tungsten oxide bronzes in ionic melts of the polytungsten salts. Among the new state – of – the art methods for their manufacture, electrochemical synthesis in ionic melts, which  makes considerably better use of existing technologies, is highly productive, based on the discharge of oxyanions of the polytungstates.  

    Keywords: oxide alkali bronzes, alkaline tungsten bronzes, tungsten, molybdenum, nonstoichiometry, tungsten oxides, electroconductivity, electrochromism

  • Amplitude- frequency characteristic (AFC ) amplifier avalanche diode mode microwave detection of amplitude-modulated optical vibrations

    Based solutions of avalanche transit diode amplifier for under the influence of microwave amplitude- modulated optical signal at the p-n junction diode is determined by the response of the amplifier , while a detector device characteristic. We investigate the influence of numerous system parameters on product detection.

    Keywords: frequency response; avalanche diode; amplifier; detector; Microwave amplitude modulated optical vibration .

  • Experimental research of the carbon cloth electrodes for recording electrical biological signals

    The article presents the results of experimental investigations of carbon fabric electrodes for recording electrical biosignals. Experimental studies of carbon fabric electrodes showed good results both in conductivity and usability, for example, for further integration into clothing, that indicates the high quality of carbon fabric electrodes and promising for further uses for cardiac monitoring.

    Keywords: Electrodes, carbon fabric, electrical biosignals, cardiac monitoring.