Summaries of the Issue
ANALYSIS OF MULTIMODAL FUSION TECHNIQUES FOR AUDIO-VISUAL SPEECH RECOGNITION Ivanko Denis V. , Kipyatkova Irina S, Ronzhin Andrey L, Karpov Alexey A
The paper deals with analytical review, covering the latest achievements in the field of audio-visual (AV) fusion (integration) of multimodal information. We discuss the main challenges and report on approaches to address them. One of the most important tasks of the AV integration is to understand how the modalities interact and influence each other. The paper addresses this problem in the context of AV speech processing and speech recognition. In the first part of the review we set out the basic principles of AV speech recognition and give the classification of audio and visual features of speech. Special attention is paid to the systematization of the existing techniques and the AV data fusion methods. In the second part we provide a consolidated list of tasks and applications that use the AV fusion based on carried out analysis of research area. We also indicate used methods, techniques, audio and video features. We propose classification of the AV integration, and discuss the advantages and disadvantages of different approaches. We draw conclusions and offer our assessment of the future in the field of AV fusion. In the further research we plan to implement a system of audio-visual Russian continuous speech recognition using advanced methods of multimodal fusion.
PHOTONICS AND OPTOINFORMATIСS
ANALOG-TO-DIGITAL CONVERSION OF SIGNALS WITH ANGULAR MANIPULATION FOR SOFTWARE DEFINED RADIO SYSTEMS Tsvetkov Alexander Yu. , Prygunov Alexander G. , Anikeichik Nikolai D. , Rybalko Igor P., Osipov Nikita A
The paper deals with the search of ways for speeding up and accuracy increase of conversion of modern analog-to-digital converters. The main shortcomings interfering a solution of this task including the field of optoelectronic analog-to-digital converters are provided. The proposed solution gives the chance to increase high-speed performance of analog-to-digital converters on the basis of holographic interferometry principles without reducing their accuracy of conversion. The optical scheme of interferential and holographic method of analog-to-digital conversion and results of its mathematical modeling are provided. Some recommendations about hardware implementation of this analog data digitizer are formulated. The physical principles and approaches to a choice of the converter structural elements are explained. An example of forming the functional scheme of a decoder for a luminous flux intensity in terms of registration of analog-to-digital converter is reviewed. The practical importance of the provided method consists in possibility of creation of analog-to-digital converters with high-speed performance about 600 MHz and with an accuracy of conversion up to 12 bits.
QUANTUM-MECHANICAL MODELING OF SPATIAL AND BAND STRUCTURE OF Y3AL5O12 SCINTILLATION CRYSTAL Vrubel Ivan I., Polozkov Roman G. , Shelykh Ivan A.
Spatial and electronic structures of a unit cell of yttrium-aluminum garnet have been studied. Quantum-mechanical model have been presented. Semi-empirical methods PM6 and PM7 have been used for geometry optimization of the crystal unit cell. Band structure has been calculated within density functional theory with the use of PBE exchange-correlation functional. Histograms of metal-oxygen distances for equilibrium geometry have been constructed. Comparison of the used methods has been carried out and recommendation about their applicability for such problems was given. The single-particle wave functions and energies have been calculated. The bandgap was estimated. The band structure was plotted. It was shown that the method gives reliable results for spatial and band structure of Y3Al5O12 scintillation crystal. The results of this work can be used for improvement of characteristics of garnet scintillation crystals.
STUDY OF INK LAYER BY METHOD OF ATTENUATED TOTAL REFLECTANCE SPECTROSCOPY Fatkhullina Dina G., Zhukova Ekaterina V., Margaryants Nikita B.
Subject of Research. Researchresults of thickness distribution of an ink layer smearedon a glass surface are presented. The orange ink which is used as a coloring pigment in writing instrument (highlighter) is selectedasan object of study. Method. Researches were carried out by the method of attenuated total reflectance(ATR) spectroscopy. The spectral setup fitted up on the basis of monochromator MDR-204 was usedin the experiment. The peculiarity of the measurement scheme is the applicationofhigh-resolution camera as a radiation detector and information storage as an images package. Researches allowed receivingexperimental data in the form of ink ATR spectra arrayfor studied areas of layer surface in a given spectral range. Main Results. The estimation of ink layer thickness was done, that gives the possibilityto visualize its distribution over the surface using three-dimensional modeling capabilities. The thickness of the ink layer is not more than 0.12 microns and arithmetic mean of the thickness is0.06 microns. The local areas are observed in an ink distribution, they have a maximum layer thickness (0.07-0.12 microns) or areas with the ink thickness less then 0.03 microns. Variation of the ink layer thicknessbetween the local areas is smooth. Practical Relevance. The proposed measuring scheme, the sequence of registration and processing of experimental data can be used to studyink distribution within the thickness of a surface layer of other materials,for example, in analysis of signs performed by an ink on paper medium in order to identify them in such areas of science as forensic science andstudy of art.
RESEARCH OF THE ENTRANCE ANGLE EFFECT ON THE REFLECTANCE SPECTRA OF THE STAINLESS STEEL SURFACE OXIDIZED BY PULSED LASER RADIATION Veiko Vadim Pavlovich, Odintsova Galina V, Karlagina Yulia Yu., Andreeva Yaroslava M., Ageev Eduard I, Yatsuk Roman M.
Subject of Research.Oxide films on the metal surfaces can be obtained both by surface-uniform infrared heating and local laser treatment e.g. by sequence of nanosecond laser pulses. Due to interference in created films the coloration of treated area is observed. The present work shows the results of spectrophotometric measurements for various light entrance angles in the range of 10-60°. Method. AISI 304 stainless steel plates were oxidized by two methods: in muffle furnace FM - 10 (Т= 500-600° С, t = 5-7 min.) and at line-by-line scanning by sequence of nanosecond laser pulses (λ = 1.06 μm, τ =100 ns, r = 25 μm,q=2.91∙107 W/cm2, Nx = 30, Ny = 1). Surface research in optical resolution was realized by Carl Zeiss Axio Imager A1M. Reflectance spectra were obtained with spectrophotometer Lambda Perkin 1050 with integrating sphere at different fixed light incidence angles. Topographic features were detected by scanning probe microscopy investigation with NanoEducator equipment. Main Results. The quantitative surface geometry characteristics of AISI 304 stainless steel patterns treated by different methods are obtained. It was found that the increase of light entrance angle has no influence on the form of reflection coefficient dependence from a wavelength, but a blue-shift occurs especially for the case of laser treatment. This difference can be caused by surface topology formed by laser heating and variety of oxide film thickness. This effect results in more significant change in observed sample color for laser treatment then for infrared heating. Practical Relevance. The results obtained in the present work can be used to implement a new element of product protection against forgery with the product marking.
FEATURES OF MULTIPLEXED HOLOGRAMS RECORDING IN PHOTO-THERMO-REFRACTIVE GLASS Ivanov Sergei A , Doan Van Bac, Ignatiev Alexander I , Nikonorov Nikolay V.
We have carried out calculations of recording conditions for multiplexed holograms in photo-thermo-refractive (PTR) glass. The proposed calculation sets the link between such parameters as: the angle between recording beams and the angle of sample rotation, operating wavelength, the angle of incidence on the element, output angle. To study recording features of multiplexed holograms on PTR glass several elements was made. Six holograms in each element were recorded with various exposures. All samples were heat-treated at one temperature around glass transition temperature. It has been demonstrated that at the recording of several gratings with a total exposure exceeding an optimal value for a given material, the total value of the refractive index modulation amplitude (n1) reaches the maximum attainable magnitude that is equivalent to a value of a single hologram with optimal exposure. It has been found that refractive index dynamic range of the material distributes between the gratings in accordance with the ratio between exposure times if holograms exposures have significant differences. In the present paper six-channel multiplexer was recorded for a wavelength equal to 632.8 nm (He-Ne laser). The diffraction angles correspond to calculations mentioned above. The n1 value in each grating is equal to the value of the highest attainable value of the value of n1 divided by the total number of multiplexed holograms.
SCALE FACTOR DETERMINATION METHOD OF ELECTRO-OPTICAL MODULATOR IN FIBER-OPTIC GYROSCOPE Aleynik Artem S, Volkovskiy Sergey A. , Mikheev Maksim V. , Nikitenko Aleksander N., Plotnikov Mikhail Yurievich
Subject of Research. We propose a method for dynamic measurement of half-wave voltage of electro-optic modulator as part of a fiber optic gyroscope. Excluding the impact of the angular acceleration on measurement of the electro-optical coefficient is achieved through the use of homodyne demodulation method that allows a division of the Sagnac phase shift signal and an auxiliary signal for measuring the electro-optical coefficient in the frequency domain. Method. The method essence reduces to decomposition of step of digital serrodyne modulation in two parts with equal duration. The first part is used for quadrature modulation signals. The second part comprises samples of the auxiliary signal used to determine the value of the scale factor of the modulator. Modeling is done in standalone model, and as part of a general model of the gyroscope. The applicability of the proposed method is investigated as well as its qualitative and quantitative characteristics: absolute and relative accuracy of the electro-optic coefficient, the stability of the method to the effects of angular velocities and accelerations, method resistance to noise in actual devices. Main Results. The simulation has showed the ability to measure angular velocity changing under the influence of angular acceleration, acting on the device, and simultaneous measurement of electro-optical coefficient of the phase modulator without interference between these processes. Practical Relevance. Featured in the paper the ability to eliminate the influence of the angular acceleration on the measurement accuracy of the electro-optical coefficient of the phase modulator will allow implementing accurate measurement algorithms for fiber optic gyroscopes resistant to a significant acceleration in real devices.
STUDY OF THE EFFECT OF ENDFACES POLISHING ANGLE FOR ANISOTROPIC WAVEGUIDES ON STATE CONVERSION OF LIGHT POLARIZATION Vladimir A. Shulepov , Aksarin Stanislav Mikhailovich, Vladimir E. Strigalev
The paper deals with optical scheme for research of polarization state transformation at the junction of anisotropic waveguides. It consists of a light source, polarization controller, multifunctional integrated optical scheme (MIOS), single-mode fiber for input and output of optical radiation in MIOS and the polarization scanning Michelson interferometer. Optical radiation from the source of the plant comes through the polarization controller in one of the MIOS ports. Further, in one of the opposite ports the radiation is received by different fibers, polished at the angles of 19.5˚, 10.5˚ and 0˚. After that, the optical radiation gets into polarization Michelson interferometer. With that, the picture visibility is analyzed at different displacement of one arm upon which the value has been determined in the polarization conversion point connections. At the course of work it was obtained that the polarization state conversion at a splicing point rises with the slant angle deviation from its optimal value. Anisotropic waveguides splicing is one of the main tasks during fabrication of any fiber-optic sensor with integrated optical elements. The results of this work are of great interest for the wide range of specialists in the optical waveguides application field.
AUTOMATIC CONTROL AND ROBOTICS
SOLUTION OF SIGNAL UNCERTAINTY PROBLEM AT ANALYTICAL DESIGN OF CONSECUTIVE COMPENSATOR IN PIEZO ACTUATOR CONTROL Bystrov Sergey V., Vunder Nina A., Ushakov Anatoly Vladimirovich
Subject of Research.We present research results for the signal uncertainty problem that naturally arises for the developers of servomechanisms, including analytical design of serial compensators, delivering the required quality indexes for servomechanisms. Method. The problem was solved with the use of Besekerskiy engineering approach, formulated in 1958. This gave the possibility to reduce requirements for input signal composition of servomechanisms by using only two of their quantitative characteristics, such as maximum speed and acceleration. Information about input signal maximum speed and acceleration allows entering into consideration the equivalent harmonic input signal with calculated amplitude and frequency. In combination with requirements for maximum tracking error, the amplitude and frequency of the equivalent harmonic effects make it possible to estimate analytically the value of the amplitude characteristics of the system by error and then convert it to amplitude characteristic of open-loop system transfer function. While previously Besekerskiy approach was mainly used in relation to the apparatus of logarithmic characteristics, we use this approach for analytical synthesis of consecutive compensators. Main Results. Proposed technique is used to create analytical representation of "input–output" and "error–output" polynomial dynamic models of the designed system. In turn, the desired model of the designed system in the "error–output" form of analytical representation of transfer functions is the basis for the design of consecutive compensator, that delivers the desired placement of state matrix eigenvalues and, consequently, the necessary set of dynamic indexes for the designed system. The given procedure of consecutive compensator analytical design on the basis of Besekerskiy engineering approach under conditions of signal uncertainty is illustrated by an example. Practical Relevance. The obtained theoretical results are used in the task of developing precise positioning systems with piezoelectric actuation mechanism. Proposed procedure for analytical synthesis of consecutive compensator is also believed to be usable for design of servo mechanisms of arbitrary application.
ADAPTIVE SELECTION OF AUXILIARY OBJECTIVES IN MULTIOBJECTIVE EVOLUTIONARY ALGORITHMS Petrova Irina A. , Buzdalova Arina S , Shalyto Anatoly Abramovich
Subject of Research.We propose to modify the EA+RL method, which increases efficiency of evolutionary algorithms by means of auxiliary objectives. The proposed modification is compared to the existing objective selection methods on the example of travelling salesman problem. Method. In the EA+RL method a reinforcement learning algorithm is used to select an objective – the target objective or one of the auxiliary objectives – at each iteration of the single-objective evolutionary algorithm.The proposed modification of the EA+RL method adopts this approach for the usage with a multiobjective evolutionary algorithm. As opposed to theEA+RL method, in this modification one of the auxiliary objectives is selected by reinforcement learning and optimized together with the target objective at each step of the multiobjective evolutionary algorithm. Main Results.The proposed modification of the EA+RL method was compared to the existing objective selection methods on the example of travelling salesman problem. In the EA+RL method and its proposed modification reinforcement learning algorithms for stationary and non-stationary environment were used. The proposed modification of the EA+RL method applied with reinforcement learning for non-stationary environment outperformed the considered objective selection algorithms on the most problem instances. Practical Significance. The proposed approach increases efficiency of evolutionary algorithms, which may be used for solving discrete NP-hard optimization problems. They are, in particular, combinatorial path search problems and scheduling problems.
AVAILABILITY RESEARCH OF REMOTE DEVICES FOR WIRELESS NETWORKS Bazhayev Nurzhan A, Krivtsova Irina E., Lebedev Ilya S
We consider the wireless network under attack, aimed at "broadcast storm" initiation, in order to determine the availability of stand-alone units and the ability to carry out their functional tasks under information exposure. We determine a set of conditions for such type of attacks on the part of potential information interloper. The functional analysis of the systems based on wireless technology is made. We examine the remote device of a self-organizing wireless network as a queuing system M/M/1/n. Model dependencies are shown for normal system performance and at information exposure on the part of potential information interloper. Analytical simulation of wireless network functioning is carried out in the normal mode and under the attack aimed at "broadcast storm" initiation. An experiment is described which provides statistical information on operation of network remote devices. We present experiment results on carrying out attack at typical system transferring data by broabcast net scanning package at different noise intensities on the part of information interloper. The proposed model can be used to determine the technical characteristics of wireless ad-hoc network, develop recommendations for node configuration, aimed at countering "broadcast storm".
HIERARCHICAL ADAPTIVE ROOD PATTERN SEARCH FOR MOTION ESTIMATION AT VIDEO SEQUENCE ANALYSIS Nguyen Van Truong, Tropchenko Andrey A
Subject of Research.The paper deals with the motion estimation algorithms for the analysis of video sequences in compression standards MPEG-4 Visual and H.264. Anew algorithm has been offered based on the analysis of the advantages and disadvantages of existing algorithms. Method. Thealgorithm is called hierarchical adaptive rood pattern search (Hierarchical ARPS, HARPS). This new algorithm includes the classic adaptive rood pattern search ARPS and hierarchical search MP (Hierarchical search or Mean pyramid). All motion estimation algorithms have been implemented using MATLAB package and tested with several video sequences. Main Results. The criteria for evaluating the algorithms were: speed, peak signal to noise ratio, mean square error and mean absolute deviation. The proposed method showed a much better performance at a comparable error and deviation. The peak signal to noise ratio in different video sequences shows better and worse results than characteristics of known algorithms so it requires further investigation. Practical Relevance. Application of this algorithm in MPEG-4 and H.264 codecs instead of the standard can significantly reduce compression time. This feature enables to recommend it in telecommunication systems for multimedia data storing, transmission and processing.
AUTOMATIC SUMMARIZATION OF WEB FORUMS AS SOURCES OF PROFESSIONALLY SIGNIFICANT INFORMATION Buraya Kseniya I. , Vinogradov l Pave D., Grozin Vladislav A., Gusarova Natalya Fedorovna, Dobrenko Natalia V. , Trofimov Vladislav A.
Subject of Research.The competitive advantage of a modern specialist is the widest possible coverage of informationsources useful from the point of view of obtaining and acquisition of relevant professionally significant information. Among these sources professional web forums occupy a significant place. The paperconsiders the problem of automaticforum text summarization, i.e. identification ofthose fragments that contain professionally relevant information. Method.The research is based on statistical analysis of texts of forums by means of machine learning. Six web forums were selected for research considering aspects of technologies of various subject domains as their subject-matter. The marking of forums was carried out by an expert way. Using various methods of machine learning the models were designed reflecting functional communication between the estimated characteristics of PSI extraction quality and signs of posts. The cumulative NDCG metrics and its dispersion were used for an assessment of quality of models.Main Results. We have shown that an important role in an assessment of PSI extraction efficiency is played by requestcontext. The contexts of requestshave been selected,characteristic of PSI extraction, reflecting various interpretations of information needs of users, designated by terms relevance and informational content. The scales for their estimates have been designed corresponding to worldwide approaches. We have experimentally confirmed that results of the summarization of forums carried out by experts manually significantly depend on requestcontext. We have shown that in the general assessment of PSI extraction efficiency relevance is rather well described by a linear combination of features, and the informational content assessment already requires their nonlinear combination. At the same time at a relevance assessment the leading role is played by the features connected with keywords, and at an informational content assessment characteristics of the post text in general come to the fore, and also the features connected with structure of a thread as the text and the social graph. We have shown that efficiency of extraction of informative posts poorly depends on a way of keywords assignment while such dependence is essential to extraction of relevant posts. The way of keywords extraction, the most effective for real appendices has been revealed. We have shown that at extraction of relevant posts linear methods are better in efficiency in comparison with nonlinear, and the LDA model is intermediate; at the same time at extraction of informative posts linear and nonlinear methods are identical by efficiency, and the LDA model considerably concedes to both of them. We have proposed substantial model explaining the received results. Practical Relevance. The obtained results can provide background for creation of new and adequate application of the existing algorithms of web forums summarization that will allow reducing significantly user’s time and resource expenditure by receiving and studying the last minute professionally significant information.
AUTHENTICATION ALGORITHM FOR PARTICIPANTS OF INFORMATION INTEROPERABILITY IN PROCESS OF OPERATING SYSTEM REMOTE LOADING ON THIN CLIENT Gatchin Yuri A, Teploukhova Olga A
Subject of Research.This paper presents solution of authentication problem for all components of information interoperabilityin process of operation system network loading on thin client from terminal server. System Definition. In the proposed solution operation system integrity check is made by hardware-software module, including USB-token with protected memory for secure storage of cryptographic keys and loader. The key requirement for the solution is mutual authentication of four participants: terminal server, thin client, token and user. We have created two algorithms for the problem solution. The first of the designed algorithms compares the encrypted one-time password (random number) with the reference value stored in the memory of the token and updates this number in case of successful authentication. The second algorithm uses the public and private keys of the token and the server. As a result of cryptographic transformation, participants are authenticated and the secure channel is formed between the token, thin client and terminal server. Main Results. Additional research was carried out to find out if the designed algorithms meet the necessary requirements. Criteria used included applicability in a multi-access terminal system architecture, potential threats evaluation and overall system security. According to analysis results, it is recommended to use the algorithm based on PKI due to its high scalability and usability. High level of data security is proved as a result of asymmetric cryptography application with the guarantee that participants' private keys are never sent in the authentication process. Practical Relevance. The designed PKI-based algorithm allows solving the problem with the use of cryptographic algorithms according to state standard even in its absence on asymmetric cryptography. Thus, it can be applied in the State Information Systems with increased requirements to information security.
GRAPH-BASED POST INCIDENT INTERNAL AUDIT METHOD OF COMPUTER EQUIPMENT Pantiukhin Igor S. , Igor A. Zikratov, Levina Alla B.
Graph-based post incident internal audit method of computer equipment is proposed. The essence of the proposed solution consists in the establishing of relationships among hard disk damps (image), RAM and network. This method is intended for description of information security incident properties during the internal post incident audit of computer equipment. Hard disk damps receiving and formation process takes place at the first step. It is followed by separation of these damps into the set of components. The set of components includes a large set of attributes that forms the basis for the formation of the graph. Separated data is recorded into the non-relational database management system (NoSQL) that is adapted for graph storage, fast access and processing. Damps linking application method is applied at the final step. The presented method gives the possibility to human expert in information security or computer forensics for more precise, informative internal audit of computer equipment. The proposed method allows reducing the time spent on internal audit of computer equipment, increasing accuracy and informativeness of such audit. The method has a development potential and can be applied along with the other components in the tasks of users’ identification and computer forensics.
ENGINEERING AND TECHNOLOGIES
ENVIRONMENTALLY FRIENDLY METHOD OF GASEOUS FUEL COMBUSTION WITH THE USE OF QUASI-OPTICAL MICROWAVE Bulat Pavel V, Bulat Mikhail P., Esakov Igor I. , Volobuev Igor A., Grachev Lev P., Denissenko Petr V.
Subject of Research.The paper deals with the problem of developing low emission combustors operating on natural gas or LPG, to reduce emissions of nitrogen oxides NOx. The possibility of burning very lean fuel mixtures is studied. To initiate the ignition and combustion stabilization the discharge generated by the quasi-optical microwave is used. Main Results. Initiating ignition by streamer microwave discharge increases the rate of combustion and combustion efficiency about four times as compared with the conventional spark ignition. Streamer discharge ignition by very lean fuel-air mixture is demonstrated with the factor of oxiding agent excess greater than the limit of explosive range under normal conditions. According to indirect indicators, ignition by microwave discharge created by quasi-optical radiation is of non-thermal nature. Microwave discharge excites oxygen atoms, and intense ultra-violet radiation is generated as a result that causes formation of cold nonequilibrium plasma with avalanche growth of free electrons. Streamer discharge propagates at a speed of 5 km /s, so the initiation of the ignition occurs immediately throughout. The temperature of the fuel mixture at the point of ignition initiation does not exceed 400 К.There is no area with a temperature sufficient to initiate thermal Zeldovich mechanism of emission of nitrogen oxides. Combustion rate is high. As a result the Fenimore mechanism of "fast nitrogen oxides" has no chance to be progressing, and NOx emissions in appreciable quantities are excluded. Energy costs are comparable with spark ignition.Practical Relevance. The studied technology is designed for low emission internal combustion engines, power gas turbines, gas compressor units, fueled by natural gas.
MODELING AND SIMULATION
FINITE MARKOV CHAINS IN THE MODEL REPRESENTATION OF THE HUMAN OPERATOR ACTIVITY IN QUASI-FUNCTIONAL ENVIRONMENT Serzhantova Maya V, Ushakov Anatoly Vladimirovich
Subject of Research. We analyze the problems of finite Markov chains apparatus application for simulating a human operator activity in the quasi-static functional environment. It is shown that the functional environment stochastic nature is generated by a factor of interval character of human operator properties. Method. The problem is solved in the class of regular (recurrent) finite Markov chains with three states of the human operator: with a favorable, median and unfavorable combination of the values of mathematical model parameters of the human operator in a quasi-static functional environment. The finite Markov chain is designed taking into account the factors of human operator tiredness and interval character of parameters of the model representation of his properties. The device is based on the usage of mathematical approximation of the standard curve of the human operator activity performance during work shift. The standard curve of the human operator activity performance is based on the extensive research experience of functional activity of the human operator with the help of photos of the day, his action timing and ergonomic generalizations. Main Results. The apparatus of regular finite Markov chains gave the possibility to evaluate correctly the human operator activity performance in a quasi-static functional environment with the use of the main information component of these chains as a vector of final probabilities. In addition, we managed to build an algorithmic basis for estimating the stationary time (time study for transit of human operator from arbitrary initial functional state into a state corresponding to a vector of final probabilities) for a used chain after it reaches the final state based on the analysis of the eigenvalues spectrum of the matrix of transition probabilities for a regular (recurrent) finite Markov chain. Practical Relevance. Obtained theoretical results are confirmed by illustrative examples, which demonstrate their suitability for possible use in the organization of the quasi-static and functional environment to solve the problems of its perfection. The results can be used for the rational organization of functional environment in which the human operators could optimally realize their potential.
EVALUATION OF ERRORS IN PARAMETERS DETERMINATION FOR THE EARTH HIGHLY ANOMALOUS GRAVITY FIELD Staroseltsev Leonid P , Yashnikova Olga M
Subject of Research.The paper presents research results and the simulation of errors caused by determining the Earth gravity field parameters for regions with high segmentation of gravity field. The Kalman filtering estimation of determining errors is shown. Method. Simulation model for the realization of inertial geodetic method for determining the Earth gravity field parameters is proposed. The model is based on high-precision inertial navigation system (INS) at the free gyro and high-accuracy satellite system. The possibility of finding the conformity between the determined and stochastic approaches in gravity potential modeling is shown with the example of a point-mass model. Main Results. Computer simulation shows that for determining the Earth gravity field parameters gyro error model can be reduced to two significant indexes, one for each gyro. It is also shown that for regions with high segmentation of gravity field point-mass model can be used. This model is a superposition of attractive and repulsive masses - the so-called gravitational dipole. Practical Relevance. The reduction of gyro error model can reduce the dimension of the Kalman filter used in the integrated system, which decreases the computation time and increases the visibility of the state vector. Finding the conformity between the determined and stochastic approaches allows the application of determined and statistical terminology. Also it helps to create a simulation model for regions with high segmentation of gravity field.
MATHEMATICAL MODEL OF RR-TYPE MICROMECHANICAL GYRO CAPACITIVE COMB-TYPE SENSORS WITH ACCOUNT FOR VIBRATIONS Evstifeev Michail I., Eliseev Daniil P
Subject of Research.The reasons for subharmonic resonances in RR-type micromechanical gyro output under linear vibrations are investigated. In ideal case, this type of gyro should be insensitive to this kind of impact due to primary and secondary angular oscillations. However, experimental results reveal significant increase in output signal under external vibrations in 20 Hz - 2 kHz bandwidth, though the device natural frequencies are above 3 kHz. This effect is caused by characteristicsnonlinearity of plate-type and comb-type capacitive sensors. Method. Mathematical model of the capacitive comb-type sensors is clarified. Electromechanical interactions in the sensors under external vibrations are described. Simulink modeling of specified mathematical model is carried out. External vibration modeling is doneby “oscillating frequency” method with constant accelerationamplitude in 20 Hz - 2 kHz bandwidth. Main Results.We have received good agreement of modeling and experimental results in the form of occurrence of subharmonic resonances under linear vibrations in three orthogonal directions. Obtained effects are explained by proposed mathematical models. The main reason for subharmonic resonances in RR-type micromechanical gyro output is that combs of stator and combs of proof mass jump out of mesh. Practical Relevance. The provided investigation gives the possibility to determine algorithmic and construction compensation methods of studied interactions for enhancing vibration resistance of RR-type micromechanical gyro.
NUMERICAL SIMULATION OF SHOCK WAVE REFRACTION ON INCLINED CONTACT DISCONTINUITY Bulat Pavel V, Volkov Konstantin N.
We consider numerical simulation of shock wave refraction on plane contact discontinuity, separating two gases with different density. Discretization of Euler equations is based on finite volume method and WENO finite difference schemes, implemented on unstructured meshes. Integration over time is performed with the use of the third-order Runge–Kutta stepping procedure. The procedure of identification and classification of gas dynamic discontinuities based on conditions of dynamic consistency and image processing methods is applied to visualize and interpret the results of numerical calculations. The flow structure and its quantitative characteristics are defined. The results of numerical and experimental visualization (shadowgraphs, schlieren images, and interferograms) are compared.
METHOD OF EQUIPMENT GRAPHIC REPRESENTATION IN THE PROCESS OF PREPRODUCTION ENGINEERING Shestakov Viktor S.
We consider the process of order determining of elements connection as a stage of preproduction engineering for the use in the design phase of production department organization structure. The initial data are: given design object (production department), operating conditions and options of equipment. Conventional approaches are considered; a new method is proposed notable for better visualization. The essence of the approach lies in replacement of the simplified contour shapes and symbolic notations on unified three-dimensional models (UTM). UTM is a three-dimensional model created from the real object - prototype by means of generalizing abstraction. The best known representative of the group is chosen as a prototype. Stepwise method of UTM creating is presented. Testing results of the method for two specific groups of technological equipment are given: screw-cutting equipment and industrial manipulators with an anthropomorphic arm. An original program module is developed that works in conjunction with additional means for information content enhancement according to the algorithm of creation of multi-component 3D-models. The proposed solution is intended for developers of automated preproduction engineering systems.
IDENTIFICATION PROPERTIES ENHANCEMENT ALGORITHM FOR PROBLEMS OF PARAMETERS ESTIMATION OF LINEAR REGRESSION MODEL Aranovskiy Stanislav V., Bobtsov Alexey Alexeevich, Wang Jian , Nikolaev Nikolay A., Pyrkin Anton Alexandrovich
This brief paper describes a new approach to identification of unknown constant parameters for a linear regression model. The main idea of the method lies in transformation of initial model into a new kind one. The new model regressor possesses identification properties or meets persistency of excitation conditions. An example of two unknown parameters identification for the linear regression model shows efficiency of the proposed approach. Simulation was carried out for a regressor with no persistency of excitation conditions, hence, parameter identification is not guaranteed.
EVALUATION OF DISTRIBUTION HISTOGRAMS FOR INCREMENT OF CHROMATICITY COORDINATES IN DISPLAY TECHNOLOGIES Zharinov Igor Olegovich, Zharinov Oleg O
We consider evaluation problem of chromaticity coordinates increment for an image displayed by indicating means (liquid crystal panels and etc.). Display device profile set by the weight matrix for components of primary colors serves as basic data for quantitative calculation. Research results have the form of mathematical expressions allowing calculation of increment values of chromaticity coordinates of the image displayed on indicating means and histograms of increment distribution.
CONDUCTOMETRY BIOTESTING AS APPLIED TO VALUATION OF THE PRO- AND ANTIBACTERIAL PROPERTIES OF CATOLITES AND ANOLITES Vladimir S.Sibirtsev , Kulakov Anton Yu. , Stroev Sergei A.
The paper deals with technique of the electrical conductivity biotesting as applied to the analysis of pro- and antibacterial activity of catolit and anolit solutions. The tested preparations were received by 25 minute electrolysis processing of 1% NaCl water solution (in cathode space) and 1% Na2SO4 water solution (in anode space) at 7 A amperage and 28 V voltage. The submitted technique is based on the analysis of change dynamics of impedance electrical conductivity of researched samples, caused by metabolic processes, realized by tested microorganisms in analyzed samples. Application of this technique enabled to show that makeup anolit solution, beginning from concentration equal to 1 vol. %, has a bacteriostatic effect on liquid culture medium with Escherichia coli in the quantity of 104 live cells on 1 ml. At anolit solution concentration more than 5 vol.% its action on the same microorganismes becomes bactericidal. At the same time, makeup catolit solution activates microorganismes vital activity as early as from concentration equal to 5 vol.%. Thus, it is shown, that electrical conductivity biotesting is a sensitive laboratory tool, granting accessible, convenient and informative way to a researcher for valuation of properties of various pro- and anti-infective preparations, as well as the other physico-chemical systems (including rather complex concerning structure and dynamics of its change), capable to act on microorganismes vital activity.
ON UNIFORMITY OF RASTER ILLUMINATION UNDER LASER SCANNING Alekseev Sergey A., Nikolay P. Belov, Kashnikov Aleksander S., Matveev Nikolay V, Prokopenko Victor T.
The paper considers the possibility of a flat light field creation (light raster) of a large size by laser scanning at a distance of several tens of meters with angular sizes equal to 20º×4º. It is shown that the filling of such size raster by light is possible with the use of a single laser. The uniformity of light raster illumination is achieved by choice of parameters for collimating and scanning optical systems, the speed of light spot movement on the line and frame, turnover frequency of frames, spot light overlap factor. We present findings that give the possibility to obtain relatively uniform raster illumination at laser scanning and the filling of large size raster with low power laser light from the radiation source.