ISSN 2224-087X (Print)
ISSN 2224-0888 (Online)

Collected scientific papers
"Electronics and information technologies"

(In 1966-2010 published under the title "Electrical engineering")

(Certificate of State Registration 17618-6468 from February 11, 2011)

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Issue 10

Issue 10, Pages: 3-22
DOI: https://doi.org/10.30970/eli.10.1
CALCULATION METHODS AT THE PLASMONIC. 2. DISCRETE-DIPOLE APPROXIMATION METHOD
I. Bolesta, A. Demchuk, O. Kushnir, I. Kolych
In this section we consider a method by which one can simulate a much larger class of plasmonic structures. The method of discrete-dipole approximation, or simply a method of discrete dipoles, as is clear from the title, represents any structure in the form of a collection of small particles that behave like dipoles. It is a direct consequence of the quasi-static approximation, that is, if the structure is larger than the wavelength of light, you can always break it into elements, each of which will be smaller. These elements will behave like dipoles, and to determine the properties of the structure, it is necessary to calculate the interaction of each dipole with the inverse field and with the field of all the dipoles of the structure. This allows to simulate the flow of any complexity, to calculate the interaction of the husband with the elements of the structure and with the external field, which is not available for other models. This method has essential features that often interfere with the practice of modeling any structures. First, this is the complexity and ambiguity of breaking the volume of the structure into dipole elements. Secondly, it requires a large number of computations. Therefore, for the effective simulation, some optimizations, such as, for example, the parallelization of computations must be implemented. The review shows solutions to these problems and examples of numerous experiments. Also, here are presented options for using the method tested by the authors. By means of the discrete-dipole approximation method, optical responses of particles of various shapes are modelled. The particles of a spherical shape show an error in the method, which depends on the partition of the figure on the dipole. The method allows you to calculate the effect on the optical feedback of the interaction between the timing. The review shows the results of such calculations, both for a pair of particles, and for the clusters of which they are composed. Also, with the aid of the discrete-dipole approximation method, a field in the vicinity of nanoparticles for a real structure is calculated. The calculation showed the existence of a local amplification of the field - "hot spots". Their existence is confirmed by the experiment.
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Issue 10, Pages: 23-30
DOI: https://doi.org/10.30970/eli.10.2
PHOTON COUNT DYNAMIC RANGE DETERMINATION FOR OPTICALLY STIMULATED LUMINESCENCE DECAY MEASUREMENTS IN YAP:Mn
D. Afanassyev, S. Ubizskii, V. Rabyk, V. Paslavsky
Margins of photon counting dynamic range have been determined experimentally for a photomultiplier tube operating in a setup for pulsed optically stimulated luminescence measurement. An effect of light exposure on the dark count has been taken into account as an addition limitation for the upper limit of light flux. The experiments have revealed that the dispersion of individual dark count readings is weakly affected by light exposure up to $6 imes 10^{5}$ s$^{-1}$,while the mean dark count is increasing. These results are used for optimizing the measurement procedure for luminescence decay.
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Issue 10, Pages: 31-40
DOI: https://doi.org/10.30970/eli.10.3
HARDWARE AND SOFTWARE COMPLEX OF INTELLECTUALIZED ORNITHOPTER-TYPE UAV FOR MILITARY APPLICATIONS
R. Diachok, I. Trach, H. Klym, I. Karbovnyk, R. Dunets
The problem of the development of miniature, cost-effective, unmanned aerial-terrestrial ornithopter for military applications is considered. Solutions from leading foreign and domestic companies and research laboratories on the design and testing of aircraft systems are analyzed. The hardware complex was built up as a small-sized ornithopter using state-of-the-art electronic components such as Ardupilot Mega 2.6 chip and a GSM module to provide autonomy and orientation in space capability. By increasing the load capacity of the device, it is possible to install additional modules, in particular, a photo or video camera and an OSD module that will allow to overlay the telemetry settings on the image transmitted from the camera. Controlled stable hovering will minimize the negative impact of vibrations that arise during the model’s wings movement and save battery life. The principal fly modes of the ornithopter have been worked out in the Mission Planner environment: manual mode, stabilization mode, return to the launch point and the flight through predefined points. There is also ability to modify and optimize autonomous flight modes, improve handling and increase the functionality of the ornithopter.
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Issue 10, Pages: 41-51
DOI: https://doi.org/10.30970/eli.10.4
THE INFLUENCE OF SURFACE ENERGY ON INCOMMENSURATE SUPERSTRUCTURES
S. Sveleba, I. Karpa, I. Katerynchuk, I. Kunyo, Ya. Shmygelsky
Phase portraits of the incommensurate superstructures described by the Livshits invariant were studies. The construction of phase portraits executed in the Python software environment using the scipy library. Using the set_integrator method, the integrator "vode" was chosen, which the usual solver of the differential equation is. The influence of parameters, the stability of the initial phase (T) and the anisotropic interaction (K), which is determined by the Dzyaloshinsky invariant on the phase portraits of the investigated system of differential equations, was considered. We have established that the anisotropic interaction described by the Dzyaloshinsky invariant leads to a violation of the spatial periodicity of the superstructure with the appearance of the amplitude and frequency modulation of the superstructure. Investigations of the stability of the system on the magnitude of surface energy were carried out. As a result, the superficial energy reduces the number of bifurcations of the system, indicating the transition of the system to a steady state. It is characterized by two mutually symmetric attractors. The system goes into a metastable state with an increase of the electric field intensity. It is characterized by a constant value of the magnitude of the wave vector of the superstructure, but not a zero mean value of the spatially modulated spontaneous polarization value. The increase of the value of the electric field, unlike to the influence of the surface energy, is accompanied by a decrease in the number of existing metastable states, and in the final stage the system passes to a state described by the existence of a single metastable state. Consequently, in contrast to the influence of surface energy, the action of an electric field does not lead to the removal of the degeneration of the investigated system. In the surface layer, an incommensurate superstructure is absent because its energy is less than the surface energy. The bulk part of the crystal is characterized by greater energy of the incommensurate superstructure in relation to the surface energy. In a thin-layer crystal, the transition from the inhomogeneous state to a homogeneous state occurs when the energy of the incommensurate superstructure becomes equal to the surface energy.
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Issue 10, Pages: 52-63
DOI: https://doi.org/10.30970/eli.10.5
THE INFLUENCE OF MECHANICAL STRESSES ON INCOMMENSURATE SUPERSTRUCTURES OF THIN-LAYER CRYSTALS
S. Sveleba, I. Katerynchuk, I. Kunyo, I. Karpa, Ya. Shmygelsky
The study of the influence of mechanical stresses on the incommensurate (IC) superstructure of fine-layer ferroelectric and ferroelastic crystals was performed Phase portraits for crystals $mathrm{[N(CH_3)_4]_2MeCl_4}$ of the group $mathrm{A_2BX_4}$, with even n were constructed. If the symmetry of a potential energy is described by a even number n, then this crystal have a spontaneous polarization. The construction of phase portraits was carried out in the Python software environment using the scipy library. It was established that mechanical stresses lead to the deformation of the superstructure, the blocking of its appearance, and the appearance of commensurate long-periodic phases. Simultaneous influence of both superficial and mechanical energy on the IC of the superstructure for ferroelectric (n = 4) and ferroelastic (n = 3) was considered. It arises if the value of the surface energy is commensurate with the energy of the incommensurate superstructure. Small values of mechanical stress lead to the deformation of the IC superstructure, which leads to the localization of the wave vector of the incommensurability on the higher order commensurate values. Further increase in the magnitude of mechanical stress leads to the appearance of chaos and blocking the IC modulation. Such an effect of the mechanical stress on the superconducting state is characteristic of both ferroelectric and ferroelastic crystals. In the work it was assumed that in the near-surface layer, the surface energy is greater than the energy of the incommensurate superstructure, which causes its absence in the near-surface layer, and the origin of the latter when it passes into the bulk part of the crystal. When the linear dimensions of the crystal are reduced, the effect of the surface defective layer will increase as a result of the reduction of the bulk part of the crystal. When the energy of an incommensurate superstructure becomes equal to the surface energy in a thin-layer (or micro-sized) crystal, the transition from the inhomogeneous state to a homogeneous state was observed. It was established that the influence of surface energy on an incommensurate superstructure in a limited-sized crystal reduces the spatial region of its existence, and also was reducing the number of existing harmonics of oscillations of the superstructure. Consequently, this is the main feature of the difference in the influence of surface energy on the IC structure, in relation to other external factors.
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Issue 10, Pages: 64-70
DOI: https://doi.org/10.30970/eli.10.6
RECOMMENDATION TECHNIQUES IN FORENSIC DATA ANALYSIS
Y. Eines
Data mining for digital forensic analysis is focused on pattern extraction from large-scale data. These patterns are used to help analysts to solve crimes. One of the most promising applications of data mining algorithms is building recommendation systems. The goal of such systems is to propose future directions of the investigation. They are especially useful for investigation with large scale collections of forensic data. In this paper I will depict one of possible architectures aiming to build recommender system for forensic data analysis. This system consists of two subsystems: clues recommendation and suspects recommendation. They can be used together as well as independently. The goal of the first subsystem is to make a list of clues based on previous investigations of other cases. First stage of clues recommendation algorithms is feature extraction. Feature extraction could be performed by NLP (Natural Language Processing) algorithms if we have text data or some other algorithms for analysis of images, videos and audios. Then for clues recommendation matrix decomposition LFA (Latent Factor Analysis) method is used. To make predictions also LFA is used. Recommendation is made by means of context filtering. The last stage is sorting of resulting data output of recommendation. The goal of the second subsystem is to make a recommendation list of suspects. This is achieved through analysis of previous cases of the same type as current case. First stage of suspect recommendation algorithm is also feature extraction, which is performed the same way as in clues recommendation algorithm. Then KNN (K nearest neighbors) algorithms is used. Next stage is collaborative prediction. Same as in clues recommendation algorithm recommendation is made by means of context filtering. The last stage is sorting of resulting data and output of recommendation. Such system should help investigators to save time which is very important at first stage of investigation.
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Issue 10, Pages: 71-85
DOI: https://doi.org/10.30970/eli.10.7
FORECASTING OF EVENTS BY TWEETS DATA MINING
B. . Pavlyshenko
This paper describes the analysis of quantitative characteristics of frequent sets and association rules in the posts of Twitter microblogs related to different event discussions. For the analysis, we used a theory of frequent sets, association rules and a theory of formal concept analysis. We revealed the frequent sets and association rules which characterize the semantic relations between the concepts of analyzed subjects. The support of some frequent sets reaches its global maximum before the expected event but with some time delay. Such frequent sets may be considered as predictive markers that characterize the significance of expected events for blogosphere users. We showed that the time dynamics of confidence in some revealed association rules can also have predictive characteristics.
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Issue 10, Pages: 86-98
DOI: https://doi.org/10.30970/eli.10.8
DIGITAL SIGNATURE CREATIONS BY USING DISCRETE COSINE AND WAVELET TRANSFORMATIONS
I. Polovynko
The bringing on of digital signature (DS)-is a method of revealing unique owner sight and used first of all for identifications and protections copyrights.Depending on the method of data conversion, the technology of applying the DS can use spatial method, frequency method and spectral connections method. At present moment methods of DS constantly perfected. Int hisreport the applying of DS two algorithms are used-DCT and WLT Selection of algorithms depends from selections by users the types of DS. The DC being processed after selections, including transformations to the grayscale. For the realizations of DCT the algorithms Hsu was used . This algorithm is used in the case, where DS is more than twice smaller from the document. For the realizations of wavelets transformations, Pitas algorithm was used. This algorithm is useful in the case of DS with size more than half of image value.
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Issue 10, Pages: 99-108
DOI: https://doi.org/10.30970/eli.10.9
STATISTICAL ANALYSIS OF THE THERMAL PARAMETERS OF SMART HOMES
O. Sinkevych, L. Monastyrskii, B. Sokolovskyi
A statistical analysis of the annual smart home sensor data obtained from REFIT smart homes project is considered. These data, in particular, consist of the high frequency external, internal, radiator surface temperatures and the gas usage values selected from 20 buildings in a period between March 7, 2014 and March 7, 2015. The data were obtained using sensors installed in twenty UK dwellings under REFIT programme dedicated to the research problem of energy savings for the smart homes. Firstly, a sqlite database for the raw data readings was created. Secondly, data preprocessing and resampling of the data were made in order to fill missing values, smooth and decrease the frequency. The correlation analysis of different data readings showed relations which allow one to use the data not only for forecasting problems, but also to formulate inverse problems of the determination of the effective thermophysical coefficients.
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Issue 10, Pages: 109-120
DOI: https://doi.org/10.30970/eli.10.10
METHOD OF USING DUAL-BOOTING AND MULTI-BOOTING OF MICROSOFT WINDOWS FAMILY OPERATING SYSTEMS ON EXTERNAL SYSTEM DRIVE
V. Kostogriz
Computer’s operating system in generally installed on its internal SSD (HDD). When user boot computer, the BIOS loads the boot loader from the internal SSD and the boot loader boots the installed operating system. A boot loader is a computer program that loads an operating system or some other system software for the computer after completion of the power-on self-tests. A boot loader is loaded into main memory from persistent memory. On modern general purpose computers, the boot up process can take tens of seconds, or even minutes, and typically involves performing a power-on self-test, locating and initializing peripheral devices, and then finding, loading and starting an operating system. Booting is complete when the normal, operative, runtime environment is attained. Dual-booting is a technique which allows a single physical computer to run two operating systems. Multi-booting allows to the common configuration of multiple operating systems on computer, and ability to choose which operating system to boot. I have Implemented method of using dual-booting and multi-booting based on the external SSD system drive.
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Issue 10, Pages: 121-132
DOI: https://doi.org/10.30970/eli.10.11
INFLUENCE OF LOW-TEMPERATURE ANNEALING IN VACUUM ON PHYSICAL PROPERTIES OF SINGLE CRYSTAL $p-mathrm{Cd_xHg_{1-x}Te}$ ($xapprox 0,28$)
V. Belyukh , B. Pavlyk
This research directed on the subsequent study of thermodynamics stability problem of $mathrm{Cd_xHg_{1-x}Te}$ (x=0,19-0,3) and is continuation of experiments on the low-temperature annealing of this alloy system. The $mathrm{Cd_xHg_{1-x}Te}$ crystals were grown from the basic components of 6N or 7N cleanness classes. With the result p type conductivity material [$N_A-N_Dapprox(2ldots 4) 10^{15}$ $^{-3}$] was obtained. The $p-mathrm{Cd_xHg_{1-x}Te}$ samples used in this investigation had a composition x=0,28. Samples were made in classical Hall configuration and annealed in a vacuum (10$^{-3}$ torr) at =373 . Influence of low temperature annealing in a vacuum on physical properties of $p-mathrm{Cd_xHg_{1-x}Te}$ ($xapprox 0,28$) was studied on the basis of the Hall coefficient measurements and conductivity measurements versus temperature, have performed on an automated dc system (standard KAMAK) in the temperature range of 80-273 . Quantitative analysis of changes of electrophysical parameters have performed on the basis of model for the $p-mathrm{Cd_xHg_{1-x}Te}$. Already after the first stage of annealing, which lasted 4 hours, the electrophysical parameters of the $p-mathrm{Cd_xHg_{1-x}Te}$ ($xapprox 0,28$) have changed significantly. The reason for such changes is a significant increase in the concentration of mercury vacancies which is a defect of the acceptor type. In particular, after the first stage of annealing, the concentration of mercury vacancies increased by almost an order of magnitude and reached the value of $[V_{Hg}]approx 2,4 10^{16}$ $^{-3}$. However, the analysis of changes in the electrophysical parameters of the $p-mathrm{Cd_xHg_{1-x}Te}$ ($xapprox 0,28$) caused by the second stage of annealing allowed us to make an assumption about the possible existence of an upper limit of the concentration of mercury vacancies that can be achieved at this annealing temperature. The simulation results give all the grounds to conclude that this value will not exceed $[V_{Hg}]approx 10^{17}$ $^{-3}$. In view of this, we can confidently assert that the electrophysical parameters of single crystal $mathrm{Cd_xHg_{1-x}Te}$ (x=0,19-0,3) in which the concentration of donors $N_D$ (n type conductivity) or the concentration of acceptors $N_A$ (p type conductivity) in the initial state $< (2ldots 3) 10^{15}$ $^{-3}$, undergo significant changes in the presence of a sample in an environment with a temperature of 353-373 K for several hours. Therefore, the conclusion that the passivation of the surface of this material is necessary to maintain the stability of the physical parameters of single crystal $mathrm{Cd_xHg_{1-x}Te}$ (x=0,19-0,3) with high mobility of charge carriers is valid not only for the material of the n-type conductivity, but also for the material of the p-type.
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Issue 10, Pages: 133-141
DOI: https://doi.org/10.30970/eli.10.12
INVESTIGATION OF POROUS SILICON PHOTOCONDUCTIVE STRUCTURES
P. Parandiy, L. Monastyrskii
Porous silicon layers photoconductive and electrical properties obtained by electrochemical etching of silicon have been investigated. Photoconductive and current-voltage properties depend on structure morphology are determined by not only properties of modified layer, but presence of charge carriers’ traps. The photosensitivity of structures with PS layers is determined by thickness of porous layer.
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