Summaries of the Issue
A METHODOLOGY FOR DESIGN SPACE EXPLORATION OF REAL-TIME LOCATION SYSTEMS Kirov Dmitry Alexandrovich, Passerone Roberto , Ozhiganov Aleхander A.
Scope of Research. This paper deals with the problem of design space exploration for a particular class of networked embedded systems called Real-Time Location Systems (RTLS). Methods. The paper contains a clear and detailed plan of anongoing research and could be considered as a review, a vision and a statement of objectives. Analytical and formal methods, simulation and automated verification will be involved in the research. Main Results. Analysis of the state of the art (current design flow, existing simulation tools and verification techniques) has revealed several limitations for performing efficientdesign space exploration of RTLS, especially for safety-critical applications. The review part of the paper also contains a clear problem statement. The main outcome of this research is the proposed vision of a novel methodology for determining the best-suited technology and its configuration from the space of potential solutions. In particular, it is planned to extend an existing simulation framework and apply automated verification techniques. The latter will be used for checking simulation results and also for exploring different system configuration alternatives, that is, to optimize the design, which is a novel approach. A case study for validating the methodology is also proposed. Practical Significance. The proposed methodology will highly increase the breadth of design space exploration of RTLS as well as the confidence on taken design decisions. It will also contribute to optimizing the design.
FIBER OPTIC SENSOR MODIFIED BY GRAFTING OF THE MOLECULARLY IMPRINTED POLYMER FOR THE DETECTION OF AMMONIUM IN AQUEOUS MEDIA Lopes Nair , Sekeira Filipa , Gomes Maria Teresa Seabra dos Reis , Rogerio Nogueira Nunes , Bilro Lucia , Zadorozhnaia Olesya A, Rudnitskaya Alisa M
Subject of Research.The paper deals with novel chemical sensors based on the polymeric optical fibers modified by grafting of the molecularly imprinted polymer for the detection of ammonium in aqueous solutions. Elevated concentrations of ammonium in surface waters lead to their eutrophication, that’s why, monitoring of the content of this ion is very important for the evaluation of surface water quality. However, currently in situ monitoring of relevant parameters in surface waters is constrained by the availability and cost of commercial sensors. Attractive approach to the development of chemical sensors for remote controls is the use of polymeric optical fibers. Polymer optical fibers have high mechanical resistance and low cost, and give the possibility for multiplexing and remote sensing. Method. Polymeric layer imprinted with ammonium ions was grafted on the surface of the methylmethacrylate fiber. Methacrylic acid was used as a monomer, ethylene glycol dimethacylate as a cross-linker, 2.2'-Azobis (2-ethylpropionamidine) dihydrochloride as a radical initiator, ammonium as a template and water:ethanol 4:1 mixture as a solvent. Optimization of the imprinted polymer synthesis conditions was carried out using intensity of transmitted light, uniformity of the grafted polymeric layer and response in the aqueous ammonium solutions as optimization criteria. Main Results. Chemical sensors based on the polymeric optical fibers modified by grafting of the molecularly imprinted polymer for the detection of ammonium in aqueous solutions have been developed. New method of the grafting of the molecularly imprinted polymer on the surface of the methylmethacrylate optical fiber has been developed. It was found out, that high concentrations of the monomer and cross-linker in the polymerization solutions cause optical fiber damage while longer polymerization times result in the decrease of the intensity of transmitted light. Optical sensor demonstrating response to ammonium in the aqueous solutions was obtained using the following experimental conditions: methacrylic acid – 2.1 mmolL-1, ethylene glycol dimethacylate – 7.7 mmolL-1 and NH4Cl – 0.3 mmolL-1 and polymerization time equal to15 minutes. Practical Relevance. Results obtained in this work are applicable in the ecological monitoring of ammonium in the surface waters, in particular, as a part of remote in situ sensing systems. Furthermore, developed optimized method of the grafting of molecularly imprinted polymer on the surface of the polymeric optical fiber is usable for the development of fiber optic sensors for detection of other compounds.
PREPARATION AND CHARACTERIZATION OF STRONTIUM FLUORIDE POWDERS ACTIVATED BY NEODYMIUM FLUORIDE Rozhnova Julia A, Kuznetsov Sergey V., Fedorov Pavel P, Voronov Valery V, Usachyov Vadim A, Kononenko Nina E, Khegai Dmitry Klimovich, Dukelskiy Konstantin V
Subject of Study. The paper deals with preparation processes of ultradisperse, homogeneous powder Sr1-хNdхF2+х (х= 0.003-0.2), with use of ammonium fluoride as the fluorinating agent taken over 114-120 % from stoichiometry. Method. Nitrate of strontium, neodymium nitrate hexahydrate, with the content equal to 99. 99 % of the basic substance and ammonium fluoride were used as the source of substances. Activated powders of strontium fluoride were obtained by the method of deposition from aqueous solutions by washing the precipitate with a solution of ammonium fluoride, taken over 114 - 120% from stoichiometry. The washed precipitate was centrifuged for 5-7 min, dried in the air at 30-350 C. Heat treatment of the dried precipitate was carried out in two stages: the first stage at the temperature of 200- 2500 C for 0.5-1 hour, the second one at 550- 6000 C for 2-3 hours. X-ray analysis of the synthesized samples was carried out on a Bruker D8 Advance diffractometer, radiation Cu K. The size and shape measuring of the particles of activated strontium fluoride was carried out by means of electron microscope Carl Zeiss NVision 40. The content of neodymium in activated powders of strontium fluoride was determined by the method of spectral emission analysis on the device LEA - S500. Chemical analysis for determination of ammonium ion (NH4+) content in the obtained samples was performed by the method of Kjeldahl. Calculations of lattice parameters, size of coherent scattering regions and the values of micro-deformations were carried out by TOPAS program. Main Results. Preparation processes of ultradisperse, homogeneous powder Sr1-хNdхF2+х (х= 0.003-0.2), with use of ammonium fluoride as the fluorinating agent taken over 114-120 % from stoichiometry, provides obtaining the firm solution Sr1-x-yNdx(NH4)yF2+x-y of the cubic fluorite structure. It has been found out that the morphology and size of the resulting product depend on the quantity of excess ammonium fluoride. The changes in the morphology of the particles from nano – and microcubes to a plate shape were made clear by varying the quantity of excess ammonium fluoride from 114% to 120%. The particle size significantly decreased with increasing excess of ammonium fluoride from 114% to 120%. After heat treatment of the obtained powders agglomeration of cubic morphology particles to a size equal to 50-350 nm without changing their shape occurred. The plate-like particles have got a rounded shape after heat treatment with size between 50 and 200 nm. Practical Relevance. Obtained mixtures with ammonium fluoride excess over 114 % and 120 % are promising for use in the technology of ceramics by hot pressing.
METHOD OF GROUP OBJECTS FORMING FOR SPACE-BASED REMOTE SENSING OF THE EARTH Grigoriev Andrey N., Zamarin Alexander I, Karavaev Maksim N
Subject of Research. Research findings of the specific application of space-based optical-electronic and radar means for the Earth remote sensing are considered. The subject matter of the study is the current planning of objects survey on the underlying surface in order to increase the effectiveness of sensing system due to the rational use of its resources. Method. New concept of a group object, stochastic swath and stochastic length of the route is introduced. The overview of models for single, group objects and their parameters is given. The criterion for the existence of the group object based on two single objects is formulated. The method for group objects formation while current survey planning has been developed and its description is presented. The method comprises several processing stages for data about objects with the calculation of new parameters, the stochastic characteristics of space means and validates the spatial size of the object value of the stochastic swath and stochastic length of the route. The strict mathematical description of techniques for model creation of a group object based on data about a single object and onboard special complex facilities in difficult conditions of registration of spatial data is given. Main Results. The developed method is implemented on the basis of modern geographic information system in the form of a software tool layout with advanced tools of processing and analysis of spatial data in vector format. Experimental studies of the forming method for the group of objects were carried out on a different real object environment using the parameters of modern national systems of the Earth remote sensing detailed observation Canopus-B and Resurs-P. Practical Relevance. The proposed models and method are focused on practical implementation using vector spatial data models and modern geoinformation technologies. Practical value lies in the reduction in the amount of consumable resources by means of space and ground-based systems in the monitoring of small and point-like objects.
METHOD OF RADIOMETRIC DISTORTION CORRECTION OF MULTISPECTRAL DATA FOR THE EARTH REMOTE SENSING Grigoriev Andrey N.
The paper deals with technologies of ground secondary processing of heterogeneous multispectral data. The factors of heterogeneous data include uneven illumination of objects on the Earth surface caused by different properties of the relief. A procedure for the image restoration of spectral channels by means of terrain distortion compensation is developed. The object matter of this paper is to improve the quality of the results during image restoration of areas with large and medium landforms. Methods. Researches are based on the elements of the digital image processing theory, statistical processing of the observation results and the theory of multi-dimensional arrays. Main Results. The author has introduced operations on multidimensional arrays: concatenation and elementwise division. Extended model description for input data about the area is given. The model contains all necessary data for image restoration. Correction method for multispectral data radiometric distortions of the Earth remote sensing has been developed. The method consists of two phases: construction of empirical dependences for spectral reflectance on the relief properties and restoration of spectral images according to semiempirical data. Practical Relevance. Research novelty lies in development of the application theory of multidimensional arrays with respect to the processing of multispectral data, together with data on the topography and terrain objects. The results are usable for development of radiometric data correction tools. Processing is performed on the basis of a digital terrain model without carrying out ground works connected with research of the objects reflective properties.
ASPHERICAL SURFACES APPROXIMATION IN AUTOMATED DESIGN OF OPTICAL SYSTEMS Ivanova Tatyana V., Romanova Galina Eduardovna, Zhukova Tatiana Ivanovna, Stepanov Yaroslav E, Bondar Ilia I, Dantsaranov Ruslan O
Subject of Research. The paper deals with the problems of higher order aspherical surfaces approximation using different equation types. The objects of research are two types of equations for higher order aspherical surfaces description used in different software for optical systems design (SАRО, OPAL, ZEMAX, CODE-V, etc.) and dependent on z-coordinate or on a radial coordinate on the surface. Conversion from one type of equations to another is considered in view of application in different software for optical systems design. Methods. The subject matter of the method lies in usage of mean square method approximation for recalculation of high-order aspherical surface. Iterative algorithm for recalculation is presented giving the possibility to recalculate coefficients for different types of equations with required accuracy. Recommendations are given for choosing recalculation parameters such as the number of result equation coefficients, the number of points for recalculation and point allocation on a surface. Main Results. Example of recalculation for aspherical surface and accuracy estimation, including result aberration comparison between initial surface and recalculated surface are presented. The example has shown that required accuracy of surface representation was obtained. Practical Relevance. This technique is usable for recalculation of higher order aspherical surfaces in various types of software for optical systems design and also for research of optimal higher order aspherical surfaces description.
PHASE SHIFT INFLUENCE RESEARCH OF THE REFERENCE OSCILLATOR SIGNAL ON THE OUTPUT SIGNAL IN HOMODYNE DEMODULATION SCHEME Volkov Anton V, Oskolkova Evgeniya S, Plotnikov Mikhail Yurievich, Mekhrengin Mikhail Viktorovich, Shuklin Philipp Alexandrovich
Subject of Research. Important feature of homodyne demodulation method based on the arctangent function approach is the phase shift between the reference oscillator signal and the interference signal. This phenomenon is caused by propagation delays of impulses in the optical interferometric sensor scheme and the analog low-pass filter in front of the phase modulator which produces the reference oscillator signal phase delay. There is multiplying of the reference oscillator signal and the interference signal in this homodyne demodulation scheme during its processing, and the phase shift between these signals leads to a distortion of the output signal. This paper deals with the findings of the phase shift influence of the reference oscillator signal by the output signal of the demodulation scheme at various parameters of the interference signal. Estimation of required accuracy is given of the phase shift compensation for the specified level distortion of the output signal. Method. Mathematical model is proposed in MATLAB. In this model, interference signal with changing parameters by a set of rules is passed through the considered demodulation scheme. This gives the possibility to obtain the dependences of the output signal amplitude from the reference oscillator signal phase shift, the operating point of the interferometer, the depth of phase modulation and amplitude of the measured phase signal. Results obtained during the simulation showed the need to compensate the reference oscillator signal phase shift. To assess this shift in the current homodyne demodulation scheme the original method of its determination has been proposed. The method is based on the transmission of the interference signal and the oscillator signal via one and the same band-pass filter that separates the phase modulation carrier frequency. According to the phase delay between the receiving signals, the value of the reference oscillator signal phase shift can be judged on. This shift can be corrected with knowledge of the value of the reference oscillator signal phase shift. Correction is achieved by making the required delay in reference oscillator signal. Main Results. The results of mathematical modeling show significant nonlinear dependences of the output signal on the reference oscillator signal phase shift at different values of the phase modulation depth, the operating point of the interferometer and the measured phase signal amplitude. It was found out that optimal values of the reference oscillator signal phase shift equal to 0, 180 and 360 provide minimum distortions of the output signal. It was shown that to achieve about 4% distortion level of the output signal phase shift compensation with an accuracy of 3% relative to period of the reference oscillator signal was required. Practical Significance. The original method making it possible to assess the value of the reference oscillator signal phase shift has been proposed. The reference oscillator signal phase shift compensation during considered homodyne demodulation scheme practical implementation provides the correctness of the scheme operation and increases the signal to noise ratio of the output signal.
AUTOMATIC CONTROL AND ROBOTICS
TRACKING CONTROL FOR A HYDRAULIC DRIVE WITH A PRESSURE COMPENSATOR Aranovskiy Stanislav V., Losenkov Andrei A, Vazquez Carlos
A problem of tracking control is considered for a hydraulic drive with a pressure compensator that is widespread in the equipment of heavy-duty machines. Method. The control problem is solved by means of a switching sliding-mode controller coupled with static nonlinear compensation and desired velocity feedforward. Main Results. Mathematical model of a hydraulic drive is given in view of the pressure compensator presence. Traditional model of a hydraulic drive is formulated for a system with a spool valve; purpose and principles of operation of the pressure compensator in hydraulic systems are described, and the extended model is presented illustrating compensator contribution to overall system dynamics. It is shown that the obtained model has an input static nonlinearity; the nonlinearity cancellation method is proposed giving the possibility for injection of a desired velocity feedforward term. The control law is chosen as a switching one and two chattering attenuation methods are studied: equivalent control estimation via filtering and sign function integration. Experimental studies are performed at a forestry hydraulic crane prototype and illustrate high tracking accuracy achieved for typical crane motions. Practical Significance. The results are suitable for heavy-duty hydraulic machines automation in construction, road building and forestry.
AN ALGORITHM OF ADAPTIVE TORQUE CONTROL IN INJECTOR INTERNAL COMBUSTION ENGINE Gerasimov Dmitriy N, Lyzlova Mariya V., Mogilevtsev Fedor L, Nikiforov Vladimir O
Subject of Research. Internal combustion engine as a plant is a highly nonlinear complex system that works mostly in dynamic regimes in the presence of noise and disturbances. A number of engine characteristics and parameters is not known or known approximately due to the complex structure and multimode operating of the engine. In this regard the problem of torque control is not trivial and motivates the use of modern techniques of control theory that give the possibility to overcome the mentioned problems. As a consequence, a relatively simple algorithm of adaptive torque control of injector engine is proposed in the paper. Method. Proposed method is based on nonlinear dynamic model with parametric and functional uncertainties (static characteristics) which are suppressed by means of adaptive control algorithm with single adjustable parameter. The algorithm is presented by proportional control law with adjustable feedback gain and provides the exponential convergence of the control error to the neighborhood of zero equilibrium. It is shown that the radius of the neighborhood can be arbitrary reduced by the change of controller design parameters. Main Results. A dynamical nonlinear model of the engine has been designed for the purpose of control synthesis and simulation of the closed-loop system. The parameters and static functions of the model are identified with the use of data aquired during Federal Test Procedure (USA) of Chevrolet Tahoe vehicle with eight cylinders 5,7L engine. The algorithm of adaptive torque control is designed, and the properties of the closed-loop system are analyzed with the use of Lyapunov functions approach. The closed-loop system operating is verified by means of simulation in the MatLab/Simulink environment. Simulation results show that the controller provides the boundedness of all signals and convergence of the control error to the neighborhood of zero equilibrium despite significant variations of engine speed. The radius of the neighborhood is far less than required level of 20 N×m that affords ground for practical implementation of the algorithm. Practical Relevance. The proposed algorithm is recommended for application in the practical problem of torque control in injector and other types of ICE.
MATERIAL SCIENCE AND NANOTECHNOLOGIES
ON THE SPECIFIC FEATURES OF SILICON CARBIDE HETEROPOLYTYPE EPITAXY Davydov Sergei Yu, Lebedev Alexander A, Usikov Alexander S.
Specific features of silicon carbide layer formation with the structure (polytype) different from the SiC-substrate structure (polytype) are considered. Simple theoretical foundations of the nonstoichiometric character, impurities, C- and Si-faces effect on the heteropolytype epitaxy (HPE) of silicon carbide are proposed. By means of Harrison’s bond orbital model it is shown that the adsorption possibility for the C-face is much greater than for the Si-face. Within the scopes of the earlier proposed models (D-model and vacancy model) it is demonstrated that the presence of impurities changes characteristic lifetimes of the HPE process and the transition layer widths: impurities which enforce the interpolytype transition decrease corresponding life-time constants and the transition layer widths. For interpretation of the polytype stripes existence within the transition layer, the model of specific spinodal decomposition taking into account vacancy concentrations variations in both SiC sublattices is used.
PEOPLE RETRIEVAL BY MEANS OF COMPOSITE PICTURES: METHODS, SYSTEMS AND PRACTICAL DECISIONS Kukharev Georgy A, Matveev Yuri Nikolaevich, Forczmański Pawel
We discuss the problem of people retrieval by means of composite pictures and methods of its practical realization. Earlier on, the problem was posed in the previous paper by the authors, and this paper deals with its further development. The starting premise here is that for the successful search of people by their sketches it is necessary to transform these sketches into sets of populations of sketches imitating evidence of «group of witnesses» and evidence with incomplete information in verbal portraits. Variants of structures for benchmark «photo-sketch» databases are presented, intended for modeling and practical realization of original photos retrieval by sketches, which new component is a population of sketches. Problems of preprocessing for initial sketches and original photos and its influence on the result of their comparison are discussed. Simple sketch recognition systems (Simple FaRetSys) and a problem of original photos retrieval by the sketches are considered. Shortcomings of such systems are shown and new decisions on extending and development of simple systems (Extended FaRetSys) are presented. Experiments on searching of original photos by sketches in the CUFS database of sketches and similar experiments on widely known FERET and CUFSF facial databases are presented. Three frameworks are offered for retrieval performance improvement. In the first one, original sketches are transformed into populations, and then in these populations the sketch similar to the given sketch (Forensic Sketch) is already defined. The class of the sketch found in a population «by definition» unambiguously corresponds to a class of the original photo. In the second framework, the Forensic Sketch is transformed to a population of sketches, and all original sketches in a benchmarking database are compared to sketches from populations of the Forensic Sketch. The class of matches is determined in the same manner as in the first framework. The third framework includes generation of a population of sketches, both from all original sketches, and from all Forensic Sketches. The further line of research is obvious: retrieval by matching between sketches of these two populations.
DISTRIBUTED GENERATION OF COMPUTER MUSIC IN THE INTERNET OF THINGS Rogozinsky Gleb G, Cherny Eugene V, Walsh Rory , Shchekochikhin Alexei V
Problem Statement. The paper deals with distributed intelligent multi-agent system for computer music generation. A mathematical model for data extraction from the environment and their application in the music generation process is proposed. Methods. We use Resource Description Framework for representation of timbre data. A special musical programming language Csound is used for subsystem of synthesis and sound processing. Sound generation occurs according to the parameters of compositional model, getting data from the outworld. Results. We propose architecture of a potential distributed system for computer music generation. An example of core sound synthesis is presented. We also propose a method for mapping real world parameters to the plane of compositional model, in an attempt to imitate elements and aspects of creative inspiration. Music generation system has been represented as an artifact in the Central Museum of Communication n.a. A.S. Popov in the framework of «Night of Museums» action. In the course of public experiment it was stated that, in the whole, the system tends to a quick settling of neutral state with no musical events generation. This proves the necessity of algorithms design for active condition support of agents’ network, in the whole. Practical Relevance. Realization of the proposed system will give the possibility for creation of a technological platform for a whole new class of applications, including augmented acoustic reality and algorithmic composition.
APPLICATION OF MICROPHONE ARRAYS FOR DISTANT SPEECH CAPTURE Mikhail B. Stolbov
Application of microphone arrays and beamforming techniques for speech information collection has significant advantages compared to systems operating with a single microphone. This paper presents a brief overview of microphone array systems for collecting distant speech information. The paper is based on an analysis of publications on the use of microphone arrays for speech information collection tasks, as well as on the author’s experience in the development and practical application of planar microphone arrays. The paper describes the main stages of the development of systems for remote capture of audio information. It provides a review of the main applications of microphone arrays, the basic types of microphone arrays and their features. The bulk of the paper deals with planar microphone arrays. We analyze the work of microphone arrays in different acoustic environments. The paper contains the basic equations for calculating the parameters of equidistant planar microphone arrays. Some methods of designing non-equidistant arrays are also mentioned (a list of references is included). We also provide a list of basic digital signal processing algorithms for planar microphone arrays, as well as a list of references on processing algorithms in the frequency domain. The paper includes a list of foreign companies offering systems based on microphone arrays for a wide range of tasks associated with the processing of speech and audio signals. We describe some state-of-the-art speech information collection systems based on microphone arrays. Some promising directions for the development of speech information collection systems using microphone arrays are described in conclusion. The material of the review is usable in designing of microphone arrays for specific practical applications.
MATRIX-VECTOR ALGORITHMS OF LOCAL POSTERIORI INFERENCE IN ALGEBRAIC BAYESIAN NETWORKS ON QUANTA PROPOSITIONS Zolotin Andrei A., Tulupyev Aleksander L, Sirotkin Alexander Vladimirovich
Posteriori inference is one of the three kinds of probabilistic-logic inferences in the probabilistic graphical models theory and the base for processing of knowledge patterns with probabilistic uncertainty using Bayesian networks. The paper deals with a task of local posteriori inference description in algebraic Bayesian networks that represent a class of probabilistic graphical models by means of matrix-vector equations. The latter are essentially based on the use of tensor product of matrices, Kronecker degree and Hadamard product. Matrix equations for calculating posteriori probabilities vectors within posteriori inference in knowledge patterns with quanta propositions are obtained. Similar equations of the same type have already been discussed within the confines of the theory of algebraic Bayesian networks, but they were built only for the case of posteriori inference in the knowledge patterns on the ideals of conjuncts. During synthesis and development of matrix-vector equations on quanta propositions probability vectors, a number of earlier results concerning normalizing factors in posteriori inference and assignment of linear projective operator with a selector vector was adapted. We consider all three types of incoming evidences - deterministic, stochastic and inaccurate - combined with scalar and interval estimation of probability truth of propositional formulas in the knowledge patterns. Linear programming problems are formed. Their solution gives the desired interval values of posterior probabilities in the case of inaccurate evidence or interval estimates in a knowledge pattern. That sort of description of a posteriori inference gives the possibility to extend the set of knowledge pattern types that we can use in the local and global posteriori inference, as well as simplify complex software implementation by use of existing third-party libraries, effectively supporting submission and processing of matrices and vectors when programming in Java, C++ or C#.
HARDWARE ENVIRONMENT FACTOR FOR CONTROL SIGNAL TRANSFER TO A PLANT IN THE SYNTHESIS PROBLEM OF DISCRETE SYSTEMS Nuyya Olga S, Peshcherov Ruslan O, Ushakov Anatoly Vladimirovich
The paper attempts to revise certain provisions of the existing theory of discrete systems in the organization of hardware environment control signal transmission to a technical plant. It is known that the formation of a digital signal in discrete control problem of continuous plant is carried out by microcontroller or micro-computer and is represented by a parallel code, which dimension is determined by the hardware used. The parallel code for a digital clock cycle of the designed system is transmitted to the terminal device of a technical continuous plant, where the digital-to-analog conversion takes place. This kind of control signal transmission to the technical plant asserts its implementation by means of parallel buses. It is known that the length of a parallel bus is limited to an amount not exceeding half a meter due to the existing interference environment with modern standards of length. Thus, if the placement of the control signal and control plant is such that their connecting bus length exceeds more than half a meter, there is the inevitable transition from the parallel control signal to an allotted serial. The paper deals with the system factors arising in the transition from the parallel control signal to the serial by modern interfaces. Provisions of the paper are illustrated by an example. This paper is intended for system analytics and channel specialists. The resulting algorithm is applicable for control of plants (electric drive, in particular) in the large industrial factories.
PROCESSING METHOD DEVELOPMENT OF CONTROL LOW-FREQUENCY SIGNALS FOR THE INTELLECTUAL TRAINER Tabakov Yuri G
The problem of control signals generating for intellectual trainer intended for the human musculoskeletal system recovery is considered. A method for low-frequency signal processing (frequency 50 Hz) readout from the surface of cerebral cortex has been developed. These signals are connected to the activity of the human brain and, directly, with α- and β-rhythms responsible for limb movements. The proposed method is based on the application of differential functions and Daubechies and Morlaix algorithms for wavelet transforms. To avoid errors occurring during low-frequency signal readout from the surface of cerebral cortex, a modular signal processing is suggested. Research was carried out on 10 male volunteers, who performed hand movement in the course of the experiment staying in a relaxed wakefulness. The findings showed that the proposed method gives the possibility for detecting the amplitude of the control signals from 5 to 15 mV in a frequency range from 10 Hz to 50 Hz. This level of signals makes it possible to adapt them for intellectual trainer control. The results are applicable in medical rehabilitation facilities, as well as in the training of athletes for competitive events.
DATA TRANSLATION BETWEEN PADS AND CAM350 Romanova Eva B., Trifonova Tatiana A.
The subject matter of the paper is the process of data translation between computer-aided design system for electronic devices PADS VX and system for technological preparation of production of printed circuit boards CAM350 10. The object of this study is two-way translation of data in these systems. Experimental researches are applied as research methods based on repeated playback of forward and reverse data translation process between PADS and CAM350 systems. The aim is to examine the challenges of data exchange between systems and to find out the ways of their solution. The basis of the work is functionality analysis of PADS and CAM350 systems while data translation, which was carried out in the course of operating experience of these systems. The paper presents advantages and disadvantages of translation methods and their comparison. Errors arising in the process are analyzed. Possible reasons of errors origination are described. The main results are recommendations for data exchange between PADS and CAM350 systems. The proposed recommendations give the possibility to optimize the exchange of data between these systems. Practical significance of the work lies in the implementation of results at LLC «Abeo». Recommendations have been used in the development of dozens of different electronic devices. The use of these results made it possible to reduce the production run-up time, to increase data transmission correctness, thereby improving the quality of products and reduction of their cost.
INCREASE OF STABILITY AT JPEG COMPRESSION OF THE DIGITAL WATERMARKS EMBEDDED IN STILL IMAGES Batura Vladimir A
Subject of Research. The paper deals with creation and research of method for increasing stability at JPEG compressing of digital watermarks embedded in still images. Method. A new algorithm of digital watermarking for still images which embeds digital watermark into a still image via modification of frequency coefficients for Hadamard discrete transformation is presented. The choice of frequency coefficients for embedding of a digital watermark is based on existence of sharp change of their values after modification at the maximum compression of JPEG. The choice of blocks of pixels for embedding is based on the value of their entropy. The new algorithm was subjected to the analysis of resistance to an image compression, noising, filtration, change of size, color and histogram equalization. Elham algorithm possessing a good resistance to JPEG compression was chosen for comparative analysis. Nine gray-scale images were selected as objects for protection. Obscurity of the distortions embedded in them was defined on the basis of the peak value of a signal to noise ratio which should be not lower than 43 dB for obscurity of the brought distortions. Resistibility of embedded watermark was determined by the Pearson correlation coefficient, which value should not be below 0.5 for the minimum allowed stability. The algorithm of computing experiment comprises: watermark embedding into each test image by the new algorithm and Elham algorithm; introducing distortions to the object of protection; extracting of embedded information with its subsequent comparison with the original. Parameters of the algorithms were chosen so as to provide approximately the same level of distortions introduced into the images. Main Results. The method of preliminary processing of digital watermark presented in the paper makes it possible to reduce significantly the volume of information embedded in the still image. The results of numerical experiment have shown that the proposed algorithm keeps higher resistance to JPEG compression, noising, Wiener filtering and brightness change. Practical Relevance. The proposed algorithm is applicable for copyright protection on the still images.
ENGINEERING AND TECHNOLOGIES
ESTIMATION OF INTRUSION DETECTION PROBABILITY BY PASSIVE INFRARED DETECTORS Volkhonskiy Vladimir V., Malyshkin Sergey L
Subject of Research. The paper deals with estimation of detection probability of intruder by passive infrared detector in different conditions of velocity and direction for automated analyses of physical protection systems effectiveness. Method. Analytic formulas for detection distance distribution laws obtained by means of experimental histogram approximation are used. Main Results. Applicability of different distribution laws has been studied, such as Rayleigh, Gauss, Gamma, Maxwell and Weibull distribution. Based on walk tests results, approximation of experimental histograms of detection distance probability distribution laws by passive infrared detectors was done. Conformity of the histograms to the mentioned analytical laws according to fitting criterion 2 has been checked for different conditions of velocity and direction of intruder movement. Mean and variance of approximate distribution laws were equal to the same parameters of experimental histograms for corresponding intruder movement parameters. Approximation accuracy evaluation for above mentioned laws was done with significance level of 0.05. According to fitting criterion 2, the Rayleigh and Gamma laws are corresponded mostly close to the histograms for different velocity and direction of intruder movement. Dependences of approximation accuracy for different conditions of intrusion have been got. They are usable for choosing an approximation law in the certain condition. Practical Relevance. Analytic formulas for detection probability are usable for modeling of intrusion process and objective effectiveness estimation of physical protection systems by both developers and users.
MODELING AND SIMULATION
FINITE ELEMENT FOR STRESS-STRAIN STATE MODELING OF TWO-LAYERED AXIALLY SYMMETRIC SHELLS Kurochka Konstantsin S., Stefanovski Igor L
Subject of Research. Computation of composite material designs requires application of numerical methods. The finiteelement method usage is connected with surface approximation problems. Application of volumetric and laminar elements leads to systems with large sizes and a great amount of computation. The objective of this paper is to present an equivalent two-layer mathematical model for evaluation of displacements and stresses of cross-ply laminated cone shells subjected to uniformly distributed load. An axially symmetric element for shell problems is described. Method. Axially symmetric finite element is proposed to be applied in calculations with use of correlation for the inner work of each layer separately. It gives the possibility to take into account geometric and physical nonlinearities and non-uniformity in the layers of the shell. Discrete mathematical model is created on the base of the finite-element method with the use of possible motions principle and Kirchhoff–Love assumptions. Hermite element is chosen as a finite one. Cone shell deflection is considered as the quantity sought for. Main Results. One-layered and two-layered cone shells have been considered for proposed mathematical model verification with known analytical and numerical analytical solutions, respectively. The axial displacements of the two-layered cone are measured with an error not exceeding 5.4 % for the number of finite elements equal to 30. The proposed mathematical model requires fewer nodes to define the finite element meshing of the system and much less computation time. Thereby time for finding solution decreases considerably. Practical Relevance. Proposed model is applicable for computation of multilayered designs under axially symmetric loads: composite high-pressure bottles, cylinder shaped fiberglass pipes, reservoirs for explosives and flammable materials, oil and gas storage tanks.
ONE-DIMENSIONAL GAS DYNAMICS PROBLEMS AND THEIR SOLUTION BASED ON HIGH-RESOLUTION FINITE DIFFERENCE SCHEMES Bulat Pavel V, Volkov Konstantin N.
One-dimensional unsteady gas dynamics problems are revealing tests for the accuracy estimation of numerical solution with respect to simulation of supersonic flows of inviscid compressible gas. Numerical solution of Euler equations describing flows of inviscid compressible gas and conceding continuous and discontinuous solutions is considered. Discretization of Euler equations is based on finite volume method and WENO finite difference schemes. The numerical solutions computed are compared with the exact solution of Riemann problem. Monotonic correction of derivatives makes possible avoiding new extremes and ensures monotonicity of the numerical solution near the discontinuity, but it leads to the smoothness of the existing minimums and maximums and to the accuracy loss. Calculations with the use of WENO schemes give the possibility for obtaining accurate and monotonic solution with the presence of weak and strong gas dynamical discontinuities.
MONOTONIC DERIVATIVE CORRECTION FOR CALCULATION OF SUPERSONIC FLOWS WITH SHOCK WAVES Bulat Pavel V, Volkov Konstantin N.
Subject of Research. Numerical solution methods of gas dynamics problems based on exact and approximate solution of Riemann problem are considered. We have developed an approach to the solution of Euler equations describing flows of inviscid compressible gas based on finite volume method and finite difference schemes of various order of accuracy. Godunov scheme, Kolgan scheme, Roe scheme, Harten scheme and Chakravarthy-Osher scheme are used in calculations (order of accuracy of finite difference schemes varies from 1st to 3rd). Comparison of accuracy and efficiency of various finite difference schemes is demonstrated on the calculation example of inviscid compressible gas flow in Laval nozzle in the case of continuous acceleration of flow in the nozzle and in the case of nozzle shock wave presence. Conclusions about accuracy of various finite difference schemes and time required for calculations are made. Main Results. Comparative analysis of difference schemes for Euler equations integration has been carried out. These schemes are based on accurate and approximate solution for the problem of an arbitrary discontinuity breakdown. Calculation results show that monotonic derivative correction provides numerical solution uniformity in the breakdown neighbourhood. From the one hand, it prevents formation of new points of extremum, providing the monotonicity property, but from the other hand, causes smoothing of existing minimums and maximums and accuracy loss. Practical Relevance. Developed numerical calculation method gives the possibility to perform high accuracy calculations of flows with strong non-stationary shock and detonation waves. At the same time, there are no non-physical solution oscillations on the shock wave front.
REMOTE SYNTHESIS AND CONTROL INFORMATION TECHNOLOGY OF SYSTEM-DYNAMIC MODELS Masloboev Andrey V, Oleynik Andrey G., Maxim Shishaev
The general line of research is concerned with development of information technologies and computer simulation tools for management information and analytical support of complex semistructured systems. Regional socio-economic systems are consideredas a representative of this system type. Investigation is carried out within the bounds of development strategy implementation of the Arctic zone of the Russian Federation and national safety until 2020 in the Murmansk region, specifically under engineering of high end information infrastructure for innovation and security control problem-solving of regional development. Research methodology consists of system dynamics modeling method, distributed information system engineering technologies, pattern-based modeling and design techniques. The work deals with development of toolkit for decision-making information support problem-solving in the field of innovation security management of regional economics. For that purpose a system-dynamic models suite of innovation process standard components and information technology for remote formation and control of innovation business simulation models under research have been developed. Designed toolkit provides innovation security index dynamics forecasting and innovation business effectiveness of regional economics. Information technology is implemented within the bounds of thin client architecture and is intended for simulation models design process automation of complex systems. Technology implementation software tools provide pattern-based system-dynamic models distributed formation and simulation control of innovation processes. The technology provides availability and reusability index enhancement of information support facilities in application to innovation process simulation at the expense of distributed access to innovation business simulation modeling tools and model synthesis by the reusable components, simulating standard elements of innovation processes. The distinctive feature of the developed technology is system-dynamic pattern description translation into XML-format. That gives the possibility forautonomous model application (without modeling environment). Proposed working-out results are domain-independent and are usablefor modeling systems engineering for different knowledge domains.
INFORMATION TECHNOLOGIES IN EDUCATION
ANALYSIS AND QUANTITATIVE ASSESSMENT FOR RESULTS OF EDUCATIONAL PROGRAMS APPLICATION BY MEANS OF DIAGNOSTIC TESTS Kon Efim L/, Freyman Vladimir I, Alexander A. Yuzhakov
Subject of Research.The problem actuality for creation, control and estimation of results for competence-oriented educational programs is formulated and proved. Competences elements and components, assembled in modules, course units and parts of educational program, are defined as objects of control. Specific tasks of proficiency examination for competences and their components are stated; subject matter of the paper is formulated. Methods of Research. Some adapted statements and methods of technical science are offered to be applied for control tasks solution, decoding and estimation of education results. The approach to quantitative estimation of testing results with the use of additive integrated differential criterion of estimation is offered. Main Results. Statements, defining conditions of certain and uncertain (indeterminacy) decision-making about proficiency examination for elements of discipline components controlled by test according to test realization results, are formulated and proved. Probabilistic characteristicsof both decision-making variants are estimated. Variants of determinate and fuzzy logic mathematic methods application for decreasing decision-making indeterminancy are offered; further research direction is selected for development of methods and algorithms for results decoding of diagnostic tests set realization. Practical Relevance. It is shown, that proposed approach to quantitative estimation of testing results will give the possibility to automate the procedure of formation and analysis for education results, specified in the competence format.
RETRIEVAL TIME RESEARCH IN TEMPORAL KNOWLEDGE BASES WITH DYNAMIC CONTENT Koroleva Julia A.
Results of retrieval time research of actual data effectiveness search in temporal knowledge bases built in the basis of state of events have been proposed. This type of knowledge base gives the possibility for quick access to relevant states as well as for history based on events chronology. It is shown that data storage for deep retrospective increases significantly the search time due to the growth of the decision tree. The search time for temporal knowledge bases depending on the average number of events prior to the current state has been investigated. Experimental results confirm the advantage of knowledge bases in the basis of state of events over traditional methods for design of intelligent systems.