The results of a patent search in the field of quality improvement of main piping valve gate’s sealing faces for the plants of nuclear power, thermal power and oil and gas industries are given

Keywords: valve gate, wedge valve, main piping, patent search, sealing face

The need for specialists who know the basics of engineering creativity and practical skills of invention and the feasibility of using this methodology for functional and technological analysis. The results of the use of the said methodology in Petrozavodsk state University.

Keywords: analysis and synthesis, methodology, technology patentable subject matter

Maximum power pointtracking algorithms are widely used in the solar converters in order to obtain maximum power from the solar array. The article provides a brief description of the work of these algorithms, description of the method of testing based on mathematical modeling using Matlab, Simulink and SimScape packages. The results of modeling and comparative analysis  of the studied algorithms, its  strengths and weaknesses revealed.

Keywords: maximum power point, maximum power point tracker, photovoltaic, buck converter, comparative study of algorithms, perturb and observe method, constant voltage method, constant current method, icremental conductance method

Vocal speech is a random process. Taking into account the fact that the main characteristics of a singing voice vary with time, in the article vocal speech is studied as an acoustic nonstationary random process. To describe this process we should calculate one of its informative parameters – the autocorrelation function. The findings show that there are some differences between the autocorrelation functions for professional and nonprofessional singers. This helps to make a quantitative assessment of a singer’s professionalism which, alongside with a vocal teacher’s subjective assessment, can present an objective view on a singer’s voice and provide a good basis for optimization of academic voice training. Moreover a teacher does not have to be technically educated because this quantitative assessment is presented in diagrams which are quite easy to assess visually. It is especially important to consider when we use the given voice assessing method in music schools, colleges and universities.

Keywords: Vocal speech, acoustic signal, nonstationary random process, autocorrelation function, the maximum autocorrelation interval, quantitative assessment

In article the structure, functional architecture and mathematical model of the system intended for automated management by information procedures in the automated information system are considered. The offered model is based on monitoring of initial and flowing conditions of the information streams subjected recomposition on the basis of operating markers by the serving router. A system kernel is the Server of configurations supporting discrete disciplines of management by service.

Keywords: information service, priority management, an information stream

In this paper we study of the local atomic and electronic structure of nanostructured condensed material for rechargeable current sources on the basis of 15mas.%V2O5/Fe/LiF nanocomposite within charge-discharge cycle. Principle component analysis (PCA) of the series of Fe K-edge spectra collected during 1 st charge showing the concentrations of the components Fe, FeF2 and V[FeV]O4. We found the changes in the V oxidation state from the analysis of the experimental Fe K- and V K- XANES spectra. Total and partial density of states of components are presented.

Keywords: nanostructured materials for rechargeable current sources, dynamics of local atomic and electronic structures, XANES, DFT

The problems of building the architecture and design of the database structure for the storage of the structure of the chemical compounds and their analysis using heuristic algorithms
Proposed the structure of the database that allows you to store information about the structure of chemical compounds with varying degrees of detail. This approach simplifies forming of the structural descriptors used to build models of "structure-property" based on the genetic algorithms.

Keywords: database architecture, chemicals, data mining, heuristics

Production lines for manufacturing of cylindrical logs for wood construction are considered in the article. Technological factors influencing on efficiency of production lines are identified and classified. Results of research can be basis for improving production lines.

Keywords: Woodworking, cylindering, technological line, wood costraction, factors

The article is concerned with designing online identification algorithm for identification plunger model for  wicket gate of Kaplan turbine adaptive control system. Algorithm is based on generalised recurrent least square method and invariant embedding method. Computer modeling using designed algorithm and using real experimental data shows that algorithm is effective.  

Keywords: adaptive control system, diagnostic system, Kaplan turbine wicket gate, plunger, linearized models, identification, recurrent least square

The article discusses one of the problems of modern software - hardware complexes for control of hydrounit  hydroelectricity plant, namely the lack of an embedded system diagnostics of technical state of various hydrounit components . In work present an approach for the implementation of diagnostic systems of one of the most important parts electro - hydraulic actuator  system to control the opening of the wicket gate. The diagnostic model and the basic control chart basic elements of electro-hydraulic converter , namely the main valve and servomotor .

Keywords: Gydroelectricity plant, hydrounit, diagnostics, modeling, control chart, electro - hydraulic actuator.

The results of research of raw materials of the logs production for timber construction are considered in the article. Length of logs (for 6 meters assortment), diameter of logs (model logs) and shape of butt (an average shape factor of butt) were studied. The model log is a volume of cylinder which is equal to a calculated volume of logs. The theoretical laws of the random variable for these values are found. The Research was conducted at LLC "Biogran" in Petrozavodsk, Republic of Karelia.

Keywords: Woodworking, cylindering, technological line, wood costraction, factors, length of a log, diameter of a log, butt

The method of digital parametric measurement of the phase shift of signals with slowly varying amplitudes of the same slowly varying instantaneous frequencies was proposed. The numerical simulations and experiments on the developed hardware and software system were carried out. The error of measurement the phase difference of harmonic signals in the experiments were not more than  0,00001 radian. The method can be used in applications where the measured value is expressed in terms of the phase difference of quasi-harmonic signals.

Keywords: quasi-harmonic signal, phase shift, real time measurements, hardware and software system

The paper considers different approaches and tools for system log files analysis. Authors describe typical cases where such analysis is required. Requirements for a multipurpose log analysis tool are stated. Three classes of log analysis tools are discussed: specialized ones, real-time analysis tools and configurable analyzers. Advantages and disadvantages of these tools are summarized. Reviewed tools are assessed in the terms of compliance to the stated requirements. Configurable analyzers are considered to be the most suitable tools for described tasks.

Keywords: system logs, semistructed form, pattern, structure recognition, records filtration

We consider the design of reusable electrodes for long-term ECG monitoring integrated into clothing. Investigated high and low frequency distortion introduced the proposed electrode system. The comparison with the standard disposable electrodes for Holter ECG monitoring. It is shown that the electrodes in the frequency band 0.5-40 Hz quality as disposable.

Keywords: Electrodes, prolonged monitoring, electrocardiogram electrode device

The results of analysis of engineering solutions with main piping’s wedge valve design for the plants of nuclear power, thermal power, oil and gas industries, based on the realized patent search, are given. The tendencies of engineering solutions development for wedge valve design are identified

Keywords: valve industry, pipeline valve, shut-off valve, wedge valve, main piping