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The report examines the applied aspects of the application of interdisciplinary knowledge in the context of the development and analysis of a model of a control object for a linear DC motor, as well as the synthesis of a control system using the state space method, the frequency method and the automated method of tuning the PID controller. The results obtained are intended for use in the course of laboratory work on the discipline “Automatic control theory”.

Accurate monitoring of microvasculature functioning enables early detection of diseases related to skin microcirculation disorders. The efficient capillaroscopy approach is to visualize and assess blood microcirculation exactly in the inflamed areas. In this paper, we propose an exoscope concept for non-invasive imaging of capillary network in skin arbitrary area. The main design aspects are briefly discussed. The described concept has been approved experimentally by in vivo mapping and analysis of microvessels in human skin.

We demonstrate a novel approach to create regular multifilament arrays under additional focusing by use of a Dammann grating. The employment of Dammann grating offers an advantage over the Hermite-Gaussian phase plates in terms of multifilament array robustness and resistance to beam imperfections and fluctuations.

The acceleration of charged particles (electrons and ions) and generation of hard X-rays from femtosecond high contrast laser-driven relativistic plasma using nanostructured bulk targets was studied. It was shown that the flux of charged particles may be significantly enhanced at interaction with nanomodified surfaces. The effect of nanostructures shape and size onto the particles energy and angular distribution was studied. Manifold increased hard X-ray flux was detected for high-Z structured targets opening the opportunity for fast X-ray imaging.

We address the problem of the quantitative cardiac activity analysis at early development stages. For this purpose, we have assembled an experimental setup for bright field microscopic imaging and analyzed Zebrafish embryos before hatching. We have developed and validated an image processing technique for the spatiotemporal analysis of the obtained data. We demonstrate that the proposed technique provides quantitative information about the cardiac activity including heartbeat rate and heart shape.

The correct diagnosis of diseases and their causes is the most important factor that directly affects the efficiency of medical treatment. There is a significant number of diseases, the differential diagnosis of which is very difficult. Some skin diseases are different in etiology and similar in appearance, for example, chronic spontaneous urticaria and urticaria vasculitis. In this paper, we propose an exoscope system for videocapillaroscopy assessment of skin microcirculation in an arbitrary areas of the human body. This device allows establishing a link between microcirculation in inflammatory tissue and the disease.

New approach to ventilation of covered pavilions with tanks of sewage treatment, including the use of waste water heat to allow air exchange organization with lesser multiplicity in comparison to the traditional scheme, is considered that provides additional energy saving and increase of ecological indicators of ventilation system.

One of the distinctive features of femtosecond laser filamentation is intensity and plasma concentration clamping. Arising due to the dynamical competition between Kerr focusing and plasma defocusing this phenomenon limits the peak intensity to the values 1014 W/cm2 and plasma concentration level to 1016 −1017 cm−3. Further increase of the beam power leads to the beam splitting and multifilament formation rather than to an intense single filament with high plasma density. However it have been recently shown that fusing several filaments by introducing additional weak focusing one can obtain significant enhancement of energy deposition in the extended region around the focus resulting in higher plasma concentration and intensity [1,2,3].

Sound propagation in shallow water over the bottom with a varying impedance is considered in the coupled normal mode approach. Water depth is assumed to be constant. Bottom roughness is not taken into account. Range-dependent impedance is only associated with the spatial variability of sound speed in the bottom. The results of 3D seismic survey conducted in the Kara Sea are taken as an input data for sound propagation modeling. Numerical simulations show that the typical horizontal gradients ~ 0.4 s−1 of the bottom sound speed provide mode coupling.

This paper investigates the control algorithms for a group of load balancing devices, installed in the distribution networks 0,4 kV. The relevance of the subject is due to the need to solve the problem of an uneven distribution of single-phase load in phases of a three-phase electrical network. As an object of computer simulation, a typical three-phase branched 0,4 kV electrical network was selected. The network under investigation contains 4 three-phase outgoing lines with single-phase consumers. The algorithm of independent and coordinated work of a group of devices is considered. In the first case, the choice of the method of connecting the outgoing lines to the source phases is made by the control unit of each device independently. In the second case, a single control unit for all devices is used. From the results of the study, it follows that the algorithm of a coordinated work allows reducing the voltage asymmetry coefficients for the zero and inverse sequences at the point the common connection of consumers to a greater extent as compared with the algorithm of independent operation. The difference in the median values of the obtained asymmetry coefficients does not exceed 3%.

Multi-motor electric drives are the systems in which torques's of two or more electric motors are summarized. This summing up may be performed directly on the common shaft or indirectly, for example, on common load. In any case there is a problem of common torque distribution among the motors for most effective use of them without overload. The common solution of the problem is to achieve equal torque distribution among the motors. There are some ways to achieve the equality of motor torques in multi motor drive. One of them is matching mechanical characteristics of the motors by correcting independently the noload speed and the hardness of all the motors of the drive. This way allows keeping desired torque distribution at variable drive load, but it requires using of two independent correction signals - for no-load speed and hardness of each the motor, that calls for need the mathematical tool to determinate the reasons of nonequal common torque distribution. The aim of the paper - determinate the reasons of non-equal torque distribution in multi-motor drive by analyzing the functional dependencies between the motor torques non-equalities and the total drive torque.

We created a mathematical model of a sodium high-pressure lamp. This model is used in production before sending lamps to the consumer. To develop the model, we used a mathematical model. An analytical method was used to describe the operation of a sodium lamp based on differential equations. We also used the singular value decomposition algorithm to find the coefficients of the ARMA model. Also, the transfer function of the ARMA model was obtained. Then we tested the models to control the quality of sodium lamps in production. The obtained results of the simulation coincide with the experimental results. A graphical dependence is obtained in the case when the standard deviation is 1. Using a series of tests based on the singular value decomposition method, we confirmed the adequacy of elaborated model by Kolmogorov-Smirnov criterion.

We present experimental and numerical data on different approaches for efficient electron acceleration and gamma production at slightly relativistic intensities: optimized artificial prepulse for solid or liquid-metal target and structured targets.

Plasma wave excitation in inhomogeneous femtosecond laser plasma due to the two plasmon decay instability is demonstrated. PIC simulation results and their experimental validation are presented.

We conducted investigation of filament spatial interactions in a weakly focused filament bundle under various types of regularization by introducing amplitude and phase modulations into the laser beam. We revealed more than 1 order of magnitude energy deposition increase in the amplitude regu- larized 4-filament bundle and conservation of the multifilament transverse pattern in the phase regularized regime.

A wideband piezoelectric transducer was used to receive signals from different filaments inside a multiple filament. A technique for calculating parameters of filaments in each laser pulse has been proposed. For a regularized superfilament created using of the amplitude mask a growth of absorbed linear energy density has been observed by more than an order compared to a single filament.

The paper presents the experimental results of the ionizing response in p-i-n diode and operational amplifier under femtosecond X-ray pulse. TW Ti:Sa femtosecond laser facility was used to create X-ray radiation. Possibility of this facility to simulate SEE is discussed.

The paper considers the problem of desired load distribution in multi-motor electric drives having semi-rigid mechanical connections of the motors with a common load. The original solutions of such a problem, when it is reduced to the loads equalization, was developed and presented in this paper. The solution is based on the motor mechanical characteristics matching referred to the output shaft. An automatic system analyzes a periodical distribution of loads among the motors in various operating conditions of the drive and generates correction signals to equalize the values of the no-load speed and the hardness for all the motors of the drive. The correction of no-speed values is going on at low loads of the motor and the hardness correction — at high loads. To check the validity of the proposed technical solution, the model of the two-motor traction electric drive was developed in the MATLAB-Simulink and used. It was shown that the proposed system provides an effective automatic equalizing of the motor torques or the tractive forces with the preservation of this effect after the system release.

The article considers algorithms of operating the multiphase unit for balancing main load based on selection of load phase connection to electric network phases with retaining an original order of load phases interlace. The influence of the operating algorithms on the load asymmetry coefficients of zero and negative sequences at the electrical point is analyzed based on computer modeling the treed three-phase electric main. The results show thresholds and limitations of the given operating algorithms. They reveal that the operating algorithm, which meters the magnitude of currents and voltages, can be used to operate the three-phase unit balancing main load when the magnitude of phase load angles, for instance municipal-domestic service load, is similar. Hardware implementation of the algorithm does not require the phase-locked loop within the unit. However, in case of asymmetry characterized by a significant difference in load angles of some particular phases, the use of this algorithm will lead to incorrect work in some instances. This drawback is rare when the operating algorithm controlling both effective ranges and values of the estimated load angle are used, but its implementation makes the unit more complicated. The paper also presents the flowchart of the balancing load unit implementing the given operating algorithms and based on the ATmega8A microcontroller. The flowchart helps operating a switching module of any power and purpose.

X-ray stereo imaging is a upcoming medical imaging technology, offering 3D observational patient tissue at significantly lower doses than computed tomography or tomosynthesis. One of the main development direction for stereo imaging is geometrical measurement of patients tissues and pathologies. Such measurements are necessary to monitor the dynamics of the treatment. But measurement in stereo X-ray imaging is based on imagined stereo model. Thus there is a need for a method of objective control operator's action during the training or to determine the measurement errors in such Stereo X-ray systems.

The article describes some of the features of the servo amplifier, developed in the NRU “MPEI” for use in multi-axis high-precision materials processing. Simplified structure of servo amplifier and some of the key components of servo drive digital control system are presented. Two ways of multi-axes control are compared: using the RS-232 interface and digital inputs/outputs, and using the CANopen standard based digital CAN protocol. The benefits of multi-axis control with the CANopen protocol are high-speed exchanges, reliability of data transmission, standardization and simple communication topology.

Strong dependency of hot electron yield and energies in relativistic laser-plasma interaction on the pre-plasma properties is demonstrated. Experimental data and numerical simulation results are presented.

The efficiency of terahertz radiation generation induced by focusing two-color femtosecond laser pulses in the air with different polarization state of the pump fields was studied. A new measurement technique for the detection of the spatio-temporal THz electric field strength distribution in an electro-optic crystal using optical interferometry was demonstrated.

In the course of mathematical modeling, correlations have been established between the parameters of the input and output holes of the pneumatic chamber and the speed of its filling and deflation at a preset temperature. Mathematical relationships, which describe the pneumatic chamber filled with air at the preset initial conditions at a certain moment of time, have been obtained. The experimental data match with the theoretical ones with the specified degree of accuracy.

X-Ray stereo imaging is a promising medical imaging modality, offering 3D observational patient tissue at significantly lower doses than computed tomography or tomosynthesis. Decrease of patient dose arises from the fact that only two images are necessary to create the stereo image. Nevertheless, the ability to measure the distance in stereoscopic X-Ray scene still remains not elaborated. This paper experimentally demonstrates the method for measuring the dimensions of the geometrical object from the X-Ray stereo and shows the possibility to get a stereo image at patient dose lower than two single X-Ray images.

4D stereo X-ray imaging is realized as the sequence of 3D stereo images in some period of time. Data for 4D stereo can be received on tomosynthesis, linear tomography or cone beam tomography units. Majority of computed tomography systems don't suits for 4D because of motion artifacts caused by organ's deformation during data collecting. Organ's movement causes geometrical measuring errors in 3D and 4D imaging. But such errors can be predicted and corrected. Correction of motion errors is based on predicted Z coordinate value for next stereo image and calculated value from acquired image.

This article discusses the option of asynchronized converter-fed motor only active power consumption by the armature.

Numerical and experimental studies of several types of 3-mm wavelength illumination antennas were carried out. The illumination antennas are intended for use in an active radio-vision system disposed in the near-field scattering region of objects. An efficient and constructive-simple leaky wave antenna was designed. The antenna is constructed on the basis of the standard rectangular waveguide with 2.4×1.2-mm cross-section.

The appreciable enhancement of relativistic plasma parameters (hot electron generation and hard X-Ray yield) by controlling the pre-plasma scalelength with complementary laser pulse is demonstrated. Experimental data and numerical simulation results are presented. Keywords— hot electron generation; pre-plasma; laser plasma

3D stereo X-ray imaging can be realized on tomosynthesis, linear tomography or cone beam tomography units. Geometry of stereo imaging depends on used unit's type. The developed algorithm for determining the coordinates for each of such X-ray units realizes geometric measurements of the object. Additional 3D stereo mode with geometrical measuring function can be useful for earlier stage of diagnostics.

We present the results of development of a 3-mm wavelength video imaging system. The external EM radiation is detected with an 8 × 8 detector array illuminated by an aspheric lens, which forms an image, and a digital control unit. Some measured characteristics of the array elements (antenna element patterns, sensitivity, etc.), optical characteristics of the imaging system (point spread function, resolution, field of view, etc), as well as parameters of the digital unit (data processing and transmission rates) are given. The developed system was used in the experiments for imaging of simple objects (one or several metal spheres of different diameters) by means of reflected monochromatic signal detection.

Basic problems arising in development of antenna elements which are used to be combined in matrixes or linear arrays for radio imaging of mm wavelengths range are the next one: 1) matching of an antenna element with a high-sensitive diode, i.e. a minimization of mismatch factor in diode frequency operating range, 2) providing of demanded radiation pattern of the element, 3) providing of minimal interaction between elements included in a linear array or 2D matrix.

Stereoscopy is one of the ways for creating 3D images in radiography. Such technique can be realized on widespread X-ray equipment. Geometrical object measurement on stereo images is realized with the help of synthesized stereo cursor, which is displayed superimposed with X-ray stereo image.

In article variants of hardware realization of system of vector management by the electric drive on a basis asynchronized switched motor with use of modern element base are considered, and also application possibility as current inverter, and inverter of pressure for a food of windings stator is shown. The analysis of modern controlers for systems of the electric drive is given and the variant of debugging of the developed algorithms on imitating Simulink-model of the electric car is offered.

A mathematical model of tree rings in the form of an interference pattern is presented. The model allows retrospective reconstruction of continuous radial growth of a tree during the entire vegetation season. The radial dependence of the wood density is considered as a certain oscillation whose phase is a strictly increasing function of radius. The radial growth is defined as a monotonic function of time, inverse with respect to the phase. Algorithms for model analysis are based on the condition of dispersion causality. Experimental results are discussed.

The mathematical models and their software implementation (computer models) for image analysis of annual tree rings to detect changes in environmental parameters reflected in the tree growth are provided. The fundamental properties of radial tree growth including the growth monotony in time and space and the speed limit are based on annual tree rings modeling, whereas the changes in wood density are considered as spatio-temporal oscillatory process. The solution of two-dimensional image analysis task of the tree rings, specifically the azimuth calculation and the average width of the maximum annual tree rings growth, the calculation of index values of the increase in the width of annual tree rings are showed. The results of analysis of environmental heterogeneity obtained at image processing of annual tree rings and the connection of increment index for Siberian cedar and summer precipitation are provided. For practical implementation of models the functional structure of a distributed computing system to process dendroecological data on LAMP freeware platform was developed.

The paper describes a novel method of localizing line segments and estimating their start and end points. The lines are ordered within the image by detecting the orientation of straight edges. Image processing structure is considered which includes directional gradient processing for obtaining straight lines from edges and filtering of lines with the prescribed line slope. It permits to order lines of this slope according to their gradient values and their lengths. Extraction of a gradient line profile is used for start and end points estimation by thresholding. The problem considered is related to reduction of an original grey-level image to a set of geometric edge position parameters. This set may be used for construction primary features for image understanding and storing. It is also useful for a comparison of different images of the same scene and for finding the mutual points for images matching.

The results of theoretical and experimental investigations of signal transmission COFDM by means of radio-relay line with the use of apparatus “Evrika” in the frequency range 12,75–13,25 GHz are presented. It has been proved that transmission rate increased in 2 times, communication range in 2–4 times in comparison with RRL with QPSK modulation due to higher energetic and spectral characteristics of RRL with OFDM.

Of a high interest now are the light fields with spatially inhomogeneous polarization state. These fields give new possibilities for many aspects of optical science and engineering. We consider a new effective method for the synthesis of light fields with predetermined polarization structure by means of specific diffractive optical element (DOE).

Filaments created during propagation of an ultrashort laser pulses in gases and solids combine high non-linearity with huge intensity and long interaction path. Four-wave mixing, coherent Raman scattering, third harmonic production and others non-linear processes were observed [1, 2]. These studies were made with focused laser beams, when interaction length depends on the Rayleigh length. In this paper we report on thorough investigation of new spectral components formation under filamentation of pre-collimated laser beam in molecular gases. These components arose at the red and blue sides of the initial spectrum and were attributed to the generation of vibrational Raman “spectral solitons” and their cascaded four-wave mixing.

We present experimental and theoretical investigation of the pulse self compression under femtosecond pulse filamentation in argon cell. It is shown that beam focal length increase and pressure in the cell decrease lead to the better pulse self-compression. Experimental and theoretical results are in good qualitative agreement.

Presented in this paper are the results of research regarding increasing of telecommunication systemspsila spectral and power efficiency due to two-level modulation.

The characteristics of an optical hydrogen sensor based on tungsten oxide film are studied. It is shown, that on velocity of initial change of light transmission of sensor in H2-air mixture it is possible to define concentration H2 rapidly. The mean of rapidly periodic decoloration of an optical sensor by transient activation of WO3/Pt film in contact with electrolyte is offered.

Summary form only given. In this paper we investigate experimentally the origin of conical emission utilizing pump-probe method. To check the role of four-wave mixing process, we tried to amplify weak probe radiation in filament created by powerful pulse. The 2 mJ 70 fs 800 nm pulse was spitted in two parts. The weak one with energy of 50 muJ was used for generation of white light which was used as probe radiation. The main part created filament in 1 cm fused silica plate. Angles between beams were chosen to satisfy phase-matching conditions of eventual parametric process. We did not observe any amplification. At the instant of temporal overlapping of the pulses, the filament served as a positive lens, decreasing the divergence of probe radiation.

Effects of image formation, sampling and reconstruction in focal plane antenna array (FPAA) MMW/SMMW imager are analyzed in terms of its spatial frequency response. Rigorous expression for the optical transfer function (OTF) of an imaging subsystem of the imager is derived. Formalism of average modulation transfer functions (MTF) for sampled imaging systems is extended for exact MTF analysis of both the entire FPAA MMW imager and its constituent subsystems.

In this paper, the advanced digital microwave communication system "Evrika MIC-RL8C" with synchronous digital hierarchy within 7.9-8.4 GHz for 155.52 Mbit/s transmission rate is considered. Structure flowchart, design peculiarities and results of the system operation are described. The system is high-efficient. It is shown that perfect techniques for signal processing improve the system characteristics

We discuss the coaxial power input in normal and superconducting RF (SRF) photoinjector cavities. Upstream coaxial power input has been previously used at the PITZ facility where the output beam tube is an intrinsic part of the coaxial transmission line into the gun. In this paper, we describe coaxial coupling from the cathode side of the gun. For normal conducting RF guns, in addition to the advantage from symmetric coupling, an emittance compensation solenoid can now be positioned close to the gun cavity to deliver optimal transverse emittance. Beam dynamics calculations demonstrate 0.8 mm-mrad at 1 nC in X-band. For an SRF gun, we present a design for coaxial input around the cathode using a superconducting coupling cell. This cell matches the external quality factor of the gun for different beam powers and there is no RF loss associated with the axial gap of the cathode. The heat input into the coaxial feed and the surface field of the coupler are discussed. For a 1.3 GHz half-cell gun cavity with stored energy of 6.6 J, a 2.5 MeV electron beam can be delivered with a peak accelerating field of 50 MV/m. At 10 mA, the external Q is 2.1 x 106 and the coaxial line power loss that must be cooled is 28 W.

In this paper, we present atomic energy and charge spectra of ions accelerated at the front of the silicon and tungsten targets irradiated by the high-contrast femtosecond laser pulse with the intensity of 3/spl middot/10/sup 16/ W/cm/sup 2/, which is delayed with respect to the cleaning nanosecond laser pulse of the 3-J/cm/sup 2/ energy density. The tremendous increase in the number of fast primary ions (Si or W) and significant growth of their maximum charge in the case of the cleaned target has been observed. The main specific features of the energy and charge spectra have been analyzed by means of one-dimensional hydrodynamic transient-ionization modeling. We are also discussing the possible impact from above threshold ionization by ambipolar field on the generation of deeply ionized fast ions.