The research of influence of periodical signal discontinuity on spectrum form is considered in the article. The numerical modeling of the system of discontinuous signals is performed. The spectrum of the system built from time discreet sampling is analyzed. The plots of the sample correlation coefficient between spectrums of continuous and discontinues signals are shown in the article. The research is needed for the development of digital measuring system for quartz plates frequency detecting.
Keywords: amplitude signal spectrum, discontinuous signal, quartz plates
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
To date, questions the reliability and continuity of electrical energy production facilities are among the most urgent , due to the transition generation companies into private hands and aggravate financial, economic and industrial- technological challenges : depreciation and obsolescence of equipment, lack of investment and other factors, influencing the power producers .
The article discusses the various valuation techniques of industrial enterprises and industrial complexes electricity . On the basis of their proposed universal method of estimating production complexes electricity , which is divided into 6 groups and includes weights . The article noted that the proposed method of estimating the weight of electric power systems operation has several advantages compared with the methods of other authors.
Keywords: electricity, electricity production complexes, investment, reliability, development
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
This paper proposes criteria for the optimal choice of a database management system (DBMS), based on the requirements to this system. Empirically assessed criteria and method of analytic hierarchy process for decision making were used to carry out the comparative analysis of several DBMSs, implementing relation data model and having similar functionalities. The obtained matrixes of pair-wise comparison are examined for concurrence by calculating indices described in the article. As a result, the database management system for the own project is rationally chosen.
Keywords: DBMS, method of analytic hierarchy process, criteria, matrixes of pair-wise
The article gives IT-companies and their software products review in the field of engineer analysis and calculation. The importance and intensive development of this sphere IT-companies through their works and service refining, that facilitates their new market segments introduction, is shown.
Keywords: CAE, engineering, intellectual property, IT-technology, software products, CAD
Questions of use of the device of the correlation analysis for an assessment of an error of a form of details of cars in cross section are considered. It is shown that use of the considered device also effectively as well as application of traditional methods of an assessment of an error of a form, however demands smaller computing expenses
Keywords: error, form, details, correlation, analysis
Thermal treatment of Fe-Co-V as an instrument to improve soft-magnetic material devices quality
The process of optimizing the thermal treatment Fe-Co-V alloys used in the magnetic torque motors is studied in order to improve the magnetic properties. It is shown that to achieve high and stable magnetic properties of the alloy it must be annealed in vacuum using inactive coatings. Regime of the annealing process depends on the quality of the original alloy. Quality verification is carried out by measuring the magnetic properties of the control samples . Identifying optimal annealing regime is based on the analysis of a phase diagram of Fe-Co alloy. In connection with that the research of influence of the heating rate , maximum temperature and holding time , cooling rate on the behavior of the magnetic parameters of the control samples is carried out. It was found that the improvement of the magnetic properties is achieved by increasing the exposure time to 6h at the cooling rate of 100 °/hr. As a result a reduction of the coercive force (60 ÷ 50 ) A / m to (28 ÷ 32 ) A / m and increased magnetic induction of technical saturation from (2,0 ÷ 2,10) Т to (2,20 ÷ 2.26 ) T. for Fe-Co-V alloy are achieved. Research of the exposure time and the cooling regime caused a decrease in coercive force of the Fe-Co alloy.
Keywords: Heat treatment , the annealing conditions , Fe-Co-V, technical saturation induction , the coercive force
Design of the protective hermetic shell of the reactor compartment of the nuclear power plant discusses in the article. The possible deformation of elements of the hermetic shell during preliminary tension and testing is considered
Keywords: protective hermetic shell; change of form; deformation; strength tests
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
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
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
Acoustic system parameters were selected and calculated: wave modes used when controlling, wave entry and frequency angles according to kind of decay process and ultrasonic attenuation. Control procedure was developed
Keywords: ultrozvuk, frequency, attenuation process, technology, acoustic system
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
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