Oleksandra Hotra

Carbazole Derivative Based Near Ultraviolet Organic Light Emitting Diode with ZnMgO:Al Anode Layer

We demonstrate the fabrication and properties of an near ultraviolet organic light emitting diode (UV OLED) that contains 2,7-di(9-carbazolyl)-9-(2-ethylhexyl)carbazole organic emitting layer and aluminum-doped magnesium zinc oxide (ZnMgO:Al) layer as transparent electrode. The obtained ZnMgO:Al layer is transparent for the wavelengths longer than 325 nm and has low resistivity of the order of 10-3 Ωcm. The UV OLED device turns on at the applied voltage of 9 V.

Synthesis of the configuration structure of digital receiver of NQR radiospectrometer

Analysis of methods for demodulation of free induction decay signal that are suitable for use in pulsed nuclear quadruple resonance radiospectrometers was performed. The structure and MATLAB Simulink model of the receive path of radiospectrometer was synthesized, in which the Software Defined Radio technology was chosen for the implementation of a quadrature detector with a filtration and quadrature reflection suppression system. The application of the principle of direct digitization of the signal made it possible to significantly reduce the length of the analog portion of the receiver, and, consequently, reduce the noise of the useful signal and the level of out-of-band higher order spectral components. Streszczenie. Przeprowadzono analizę metod demodulacji sygnału zaniku indukcji swobodnej, które są odpowiednie do stosowania w impulsowych radiospektrometrach jądrowego rezonansu kwadrupolowego. Opracowano strukturę i model ścieżki odbiorczej radiospektromeru w środowisku MATLAB Simulink, w którym do realizacji kwadraturowego detektora z układem filtracji i tłumienia odbicia kwadraturowego wybrano oprogramowanie Software Defined Radio. Zastosowanie zasady bezpośredniej cyfryzacji sygnału pozwoliło znacznie zmniejszyć długość analogowej części odbiornika, a w konsekwencji zmniejszyć szum sygnału użytecznego oraz poziom pozapasmowych składowych widmowych wyższych rzędów. (Synteza struktury konfiguracji odbiornika cyfrowego radiospektromeru NQR).

Application of a statically configured FPGA in the digital control system of the NQR radio spectrometer

The digital control system of pulsed nuclear quadrupole resonance (NQR) Fourier radio spectrometer of laboratory type is developed, the main functional-algorithmic methods of which are implemented in field-programmable gate array (FPGA) Cyclone EP1C12F324. The algorithm of the proposed program and the configuration structure of the IC, created by means of the syntax of modeling the dynamic modes of logical structures on the basis of the finite state machine and functional modules, provide for the adjustment of all necessary NQR operation modes of the spectrometer and the operative control over the performance of the radiophysical experiment. The transfer of commands to the execution units of radiospectrometer at a rate of 3.15 Mbit/s is provided through a 4-bit parallel interface.

Correction of dynamic characteristics of temperature measuring devices

The correction method of dynamic characteristics of temperature measuring devices is proposed. It is based on the measurement of the RTD’s resistance value at a certain moment of the beginning of the transition process with subsequent calculation (by developed algorithm) of the given RTD’s resistance value corresponding to the measured temperature value. The structural scheme of the thermoresistive converter with the RTD pre-heating to the initial temperature value of the measuring range and with microprocessor calculation of the measured temperature value has been developed. The accuracy of temperature determination in this case is mainly determined by the accuracy of temperature measurement at a time instant t of the transition process beginning chosen less than the time constant of the RTD t <τ . It has been found that the proposed temperature measuring device provides the measurement accuracy of 0.05 °C at the measurement time t=0.1τ.

Optimal control of copper concentrate blending and melting based on intelligent systems

The possibilities of use of intelligent systems in automation of production and technological processes are considered. The intelligent system for optimal control of copper concentrate blending and melting is developed. The paper presents the results of the investigation of the intelligent system for optimal control of copper concentrate blending and melting using neural network (Matlab NNTool), adaptive neuro-fuzzy (hybrid network Matlab Anfis) and fuzzy inference (Matlab Fuzzy Logic) modelling. Streszczenie. W artykule opisane zostały możliwości wykorzystania inteligentnych systemów sterowania w automatyzacji procesów produkcyjnych I technologicznych. Przedstawiony został system do optymalnego sterowania topieniem i wzbogacaniem koncentratu miedzi. W artykule przedstawiono również wyniki badań symulacyjnych przedstawionego systemu z wykorzystaniem sieci neuronowych (Matlab NNTool), rozmytych (sieć hybrydowa Matlab ANFIS) i logiki rozmytej (Fuzzy Logic) (Sterowanie optymalne procesem rozdrabiania i roztapiania wsadu miedzianego w oparciu o systemy inteligentne).

Determination of blood flow velocity in vessels of the bulbar conjunctiva

The paper presents the methods and the system for registration of digital video recordings of the sclera with a spatial resolution of 2 μm. The pulsed illumination of the sclera was used to eliminate the image blurring caused by the continuous movement of the eyes. At evaluation of blood flow velocity the stabilization of the position of recorded images relatively to the first image frame is used and the trajectory of displacement of the bulbar conjunctiva of the eye is determined. Streszczenie. W artykule omówiono metody oraz opisano system do rejestracji cyfrowych nagrań wideo twardówki z rozdzielczością przestrzenną 2 μm. Zastosowano impulsowe oświetlenie twardówki w celu eliminacji rozmycia obrazu spowodowanego przez ciągły ruch gałek ocznych. Przy ocenie szybkości przepływu krwi przeprowadza się stabilizację pozycji zarejestrowanych obrazów względem pierwszej ramki obrazu oraz wyznacza się trajektorię przemieszczenia spojówki gałki ocznej. (Wyznaczenie szybkości przepływu krwi w naczyniach spojówki gałki ocznej).

Optimal control of blending and melting of copper concentrates

The mathematical models of the melting process, the optimization criterion and constraints on the input and controlling variables and the values of the conductivities of the melt under the electrodes and the phase voltages are used to solve the optimization problem of the electrical regime of the electric furnace. In this paper the optimal variant of the electrical regime of the furnace for the electromelting and blending processing of copper concentrates is considered, which can be provided by the optimal immersion of electrodes. The optimal parameters of the technological process of electromelting and blending are calculated. The proposed mathematical model could be applied for melting process optimization.

ZnMgO:Al Anode layer for organic light emitting diode based on carbazole derivative

We demonstrate the fabrication and properties of an near ultraviolet organic light emitting diode (UV OLED) that contains 2,7-di(9-carbazolyl)-9-(2-ethylhexyl)carbazole organic emitting layer and aluminumdoped magnesium zinc oxide (ZnMgO:Al) layer as transparent electrode. The obtained ZnMgO:Al layer is transparent for the wavelengths longer than 325 nm and has low resistivity of the order of 10−3 Ωcm. The UV OLED device turns on at the applied voltage of 9 V.