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 4

Issue 4, Pages: 3-23
The physics of optical computers
I. Polovynko, T. Kril
This paper describes the foundations of optical computer physics (OC). To further increase the performance of OC we should be using photon instead of electron. This theoretically would allow to incirease the speed almost 103 times and keep the same size of devices. We Analyzed the existing information processing systems and the possibility of creating integral-optical elements OC. It is noted that the priority at present time is creating miniature optical processors, which are based on optical transistors (OT). We describe some current (circular resonators) and future (nanoparticles) OT .
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Issue 4, Pages: 24-38
Ampere’s law and paradoxical experiments in electrodynamics
V. Petuschak, N. Kozlova, B. Osyka
The purpose of this work consists in furnishing proofs of inadequacy of actual interpretation of Ampere’s law which is based on recognition of infringement of Newton’s third law in case of magnetic interactions of conductors with current, and offer and vindicate an adequate version of this law interpretation. A series of so called "paradoxical" experiments in Electrodynamics serves the basis for the physicists to recognize infringement of Newton’s third law. Studying these experiments Russian physicist G. Nikolayev proved that Newton’s third law is true for magnetic interactions of current-carrying conductors. The peculiarity of these experiments is infringement of the principle of orthogonality of the magnetic force relative to conductor’s axis which results from Ampere’s law. Nikolayev suggested an empiric formula for modified Ampere’s law, then Newton’s third law becomes true and magnetic forces which act on elements of conductors, are not orthogonal to their axes and may even have axial direction. The authors hereof, basing on the properties of relativity of force interactions of conducting elements, theoretically deduced this formula.
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Issue 4, Pages: 39-45
Relaxed optics: problems of modeling of processes of reirradiation
P. rokhimchuck, I. Dmytruk
The problem of influence of reirradiation on generation of irreversible changes in laser-irradiated materials is analysed. Difference between processes of reirradiation and radiative-stimulated diffusion is shown. These phenomena are analysed for indium antimonide. Models,which are necessary for explanation of proper experimental data are represented and discussed.
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Issue 4, Pages: 46-52
Cherenkov radiation as effect of nonlinear and relaxed optics
The problem of Cherenkov radiation as effect of Nonlinear and Relaxed Optics is analyzed. Basic models of this phenomenon, including microscopic, are represented. Basic models of self-focusing and self-trapping phenomena are discussed. Hypothesis of formal analogy between "cone" part of self-focusing and self-trapping phenomen and Cherenkov radiation is proved too.
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Issue 4, Pages: 53-64
Luminescence of PbWO4: Tb and CdWO4: Tb, Li crystals at the photon excitation
S. Novosad, L. Kostyk, I. Novosad, A. Luchechko, M. Partyka, T. Teplyy
The comparative analysis of the results of the luminescence study of PbWO4:Tb and CdWO4:Tb, Li crystals under synchrotron and optical excitations has been carried out in this work. In the case of excitation by photons in the region of 88 nm (14.09 eV) the luminescence of the weakly doped PbWO4: Tb crystal at 8 K is mainly due to the characteristics of the PbWO4 centers. In the heavily doped CdWO4:Tb, Li crystal at the excitation of synchrotron radiation in the region of the fundamental absorption at 10 K, a luminescence caused by ions Tb3+ has been observed on the background of matrix emission. From the reviewed literature data and the our results follows that matrix luminescence of PbWO4:Tb and CdWO4:Tb, Li is due to the self-trapped excitons localized on defects. Low-temperature luminescence of these crystals is being efficiently excited by synchrotron radiation in the region of long-wavelength fundamental absorption edge and in the region of photon multiplication. Mainly Tb3+ luminescence, which is due to the transitions within the 4f8-configuration from the excited 5D4 states on the 7FJ level is observed by optical excitation of PbWO4: Tb and CdWO4: Tb, Li crystals in the range of the impurity absorption at 300 K. Differences in the cation composition and the lowering of crystal symmetry structure of the investigated tungstates from tetragonal to monoclinic not change the regularities of luminescence of terbium ions.
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Issue 4, Pages: 65-73
Effect of surface modification on luminescence spectra of NC CdS
V. Smyntyna, B. Semenenko, V. Skobyeyeva, M. Malushyn
In this paper we have investigated the influence of interfacial surface processes on the luminescence. Found that humidity influences the recombination processes in nanocrystals (NC) CdS. We found fotostimulation shortwave band radiation λmax = 480 nm. Shown that the hydroxyl group of water molecules are involved in the surface modification of nanocrystals. Based on the experimental studies of localization of photoinduced band relative to the absorption spectrum, the temperature dependence of luminescence intensity and emission studies in air and vacuum the nature and mechanism of recombination was detected, which causes luminescence with λmax = 480 nm.
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Issue 4, Pages: 74-80
The influence of values on the synthesis of CdS nanocrystals and their optical properties
V. Smyntyna, V. Boshernitsan, V. Skobeeva, N. Malushin
We have investigated the influence of solution pH on the formation of nanocrystals and their size in the process of synthesis. We have analyzed the optical absorption spectra and luminescence of colloidal solutions of NC CdS. Nanocrystals of cadmium sulphide were obtained by sol-gel technology in gelatin solution which has different pH values pH (6-10). There has been established the dependence of the contour of luminescence spectra from pH values. A decrease was observed in the average size of the nanocrystals from 8 till 3.5 nm while reducing pH from 10 to 6.
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Issue 4, Pages: 81-87
Generation (Tl0-Tl2+)-complementary pairs in alkali-halide crystals
Z. Chornij, M. Panasiuk, N. Djachuk, I. Pirko, V. Salapak
Calculated kinetics of activator color centers in ion crystals. In the one-dimensional model of ionic crystals calculated radiation parameters alkali halide crystals doped with thallium ions. It is shown that the probability of generation of color centers under the action of ionizing radiation is less than the probability of highlighting action and it falls rapidly with decreasing concentration of the activator. The concentration of color centers is of the order of 10% of the activator concentration at the saturation stage. Calculated the energy required to create a pair of color centers and kinetics of increase in their number.
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Issue 4, Pages: 88-94
Choice of working point of semiconductor temperature sensors
B. Pavlyk, A. Hrypa, A. Lenovenko, R. Didyk, R. Lys, D. Slobodzyan, J. Shykoryak, . Kushlyk
The influence of X-ray irradiation and weak magnetic field on electrophysical parameters of thermal sensors based on 2T363A transistor p-n-junction has been investigated. From the analysis of current-voltage characteristics it is shown that at the initial stage of X-ray radiation influence the increase of efficiency of recombination processes in the space charge region (SCR) and slight decrease of the direct current are observed. The external magnetic field (B = 0,17 Tl) does not change the efficiency of recombination processes in SCR, but make the impact on the diffusion component of direct current through p-n-junction. It is shown that thermosensor working point should be chosen on the area where the current-voltage characteristics overlap. The effect of X-rays (D < 325 Gy) and weak magnetic field (exposure to 15 hours) almost did not change the temperature response curve.
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Issue 4, Pages: 95-102
Influence of delay in control onto quadrocopter’s flight
B. Blahitko, Yu. Mochulsky
The investigation of mathematical model of quadrocopter with proportionally-differential control in the aspect of flight stabilization and optimal leading of quadrocopter to a specified operating mode taking into account the electro engines properties is presented. Mathematical model of a quadrocopter is defined as a 16th order system of differential equations in a Cauchee form. The input information consists of flight height, pitch, roll and yaw angles and their time variations. PD-controller is implemented with a microcontroller and changes the propellers motive force by setting the voltage of the four electro engines. We consider A test problem of automatic performing of a simple pilotage figure - a horizontal figure-of-eight (with both left and right turns) is considered. The influence on a flight of time delay in the microcontroller between the input of a quadrocopter’s status and the output of calculated voltage trajectory was investigated.
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Issue 4, Pages: 103-110
The mechanical stresses influence on inhomogeneous states in microcrystals with incommensurate superstructure
I. Karpa, S. Sveleba, I. Katerynchuk, Ya. Shmygelsky, I. Kunyo, O. Fitsych
The influence of the thickness of the microcrystals on the spatial heterogeneity of the order parameter is investigated. The heterogeneous structure in a model of Lifshitz invariant, without constant amplitude approximation is investigated. It is shown that the mechanical stresses in the microcrystals resulting from mismatches of coefficients of linear expansion of the crystal and the substrate. The mechanical stresses change the spatial behavior of the amplitude and phase of the order parameter incommensurate superstructure. Also, the mechanical stresses cause the doubling period superstructure (occurrence of bifurcations), which leads to the appearance of wave superposition existing wave modulation and chaotic structure.
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Issue 4, Pages: 111-119
Comparison of methods of local truncation error estimation for different integrators
Ya. Kost, J. Khvyshchun, Ya. Shmygelsky
The algorithms of evaluation of local truncation errors for the most widespread methods of integration are given. The method of such evaluation is offered for the trapezoidal integrator. The set of the test problems with known analytical solution is given. These problems solved with different intergators. Conclusions about the effectiveness are made.
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Issue 4, Pages: 120-126
Modeling of photoconductivity of porous silicon with spherical and cylindrical geometry of pores (english)
L. Monastyrskii, B. Sokolovskii, M. Pavlyk
This paper investigates by the finite element method the influence of inhomogeneity in the distribution of pores on the photoconductivity of porous silicon. For cylindrical pores the significant influence the Gaussian distribution of pore radii takes place for small distances between the centers of pores (R* ~ 0,2) and at low velocities of surface recombination of photocarriers (S* ~ 5). Typical part of the photoconductivity growth with increasing the distance between the centers of pores has a saturation region for low surface recombination velocity (S* ~ 5). For porous silicon with a cylindrical pore geometry the photoconductivity decrease due to recombination processes at the same radii of pores between the centres and surface recombination velocities is several times more substantial than for the porous silicon with a spherical pore geometry. The results obtained can be used for creating sensory devices operating on the peculiarities of the photoconductivity effect of porous materials.
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Issue 4, Pages: 127-140
Numerical simulation of the mechanical interactions in processes of thrusting in Earth’s crust
V. Fourman, N. Khomyak, L. Khomyak
Finite element models are used to simulate tectonic compression of sedimentary rocks by sub-merged stage and take into account frictional slipping on the detachment horizon. Numerical results show specific features of the inhomogeneous stress fields for small (0.01-0.5), middle (0.5-0.64), large (0.64-0.8) and overlarge (0.8-1.15) friction coefficients. The magnitude of the tangential contact stress controls the front between sliding and sticking zones. Stress trajectories enable to predict thrust structures using Mohr-Coulomb failure criterion.
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Issue 4, Pages: 141-147
Determining of complex magnetic permeability of the ferromagnetic material by complex impedance of inductance coil with ferromagnetic core
D. Trushakov, S. Rendzinyak, . Vasylchyshyn
In the work there has been presented the method of determining of complex magnetic permeability of ferromagnetic material by the results of measuring complex impedance of inductance coil with ferromagnetic core. The complex impedance of the inductance coil was measured with immitance measuring device "E7-25"
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Issue 4, Pages: 148-155
Software support of practical lessons in programming
V. Bondariev
The paper proposed the software and methodology support for practical lessons on programming. Methodological basis of proposals is a collection of tasks and automatic verification of programs written by students. The software consists of a client-server application that runs on the LAN. As experience has shown the proposed approach increases student interest and makes them work more intensively and at the same time relieves the teacher from routine and allows him to individualize the learning process.
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Issue 4, Pages: 156-173
Specialized distributions for educational and research institutions
E.R. Alekseev, V.I. Rodionov, O.V. Chesnokova, S.S. Chopovskyy
Using of free distribution in educational and research institutions are justified. Technique for creating a local repository of free software described. Applications for building operating systems are considered. Recommendations for building your own Linux distributions.
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© Ivan Franko National University of Lviv, 2011

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