Wyniki wyszukiwania - BazTech

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Selekcja cech osobniczych sygnału mowy z wykorzystaniem algorytmów genetycznych

Kamiński Kamil, Dobrowolski Andrzej P., Majda Ewelina

Inżynieria Bezpieczeństwa Obiektów Antropogenicznych

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2019

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Nr 1-2

8--16

PL

W referacie przedstawiono system automatycznego rozpoznawania mówcy zaimplementowany w środowisku Matlab oraz pokazano sposoby realizacji i optymalizacji poszczególnych elementów tego systemu. Główny nacisk położono na wyselekcjonowanie cech dystynktywnych głosu mówcy z wykorzystaniem algorytmu genetycznego, który pozwala na uwzględnienie synergii cech podczas selekcji. Pokazano również wyniki optymalizacji wybranych elementów klasyfikatora, m.in. liczby rozkładów Gaussa użytych do zamodelowania każdego z głosów. Ponadto, podczas tworzenia modeli głosów zastosowano model głosu uniwersalnego.

EN

The paper presents automatic speaker recognition system, implemented in the Matlab environment, and demonstrates how to achieve and optimize various elements of the system. The main emphasis was put on features selection of speech signal using a genetic algorithm, which takes into account synergy of features. The results of the selected elements of optimizing classifier have been also shown, including the number of Gaussian distributions used to model each of the voices. In addition during creating voice models, the universal voice model have been used.

2

A study of ruthenium-based catalysts used in homogeneous transfer hydrogenation of acetophenone

Mikołajczyk Filip, Kamiński Kamil

Chemical and Process Engineering

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2019

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Vol. 40, nr 2

213–-222

EN

A detailed comparison of catalytic properties of two different ruthenium-based catalysts in the reaction of homogeneous hydrogenation of acetophenone was performed. Additionally, methods of synthesis of both catalysts were tested and optimized in order to achieve the best possible quality and purity of the final catalysts. NMR analysis was used to analyze and identify the composition of ruthenium compounds and gas chromatography was used to analyze the conversion rate of hydrogenation reactions. It was determined that RuCl2(PPh3)3 obtained with a modified method described by Shaw’s group (Shawet al., 2007) had the best catalytic properties in the reaction performed under conditions described in Liang Wang’s publication (Wang et al., 2014). It was also determined that for concentration ratio of substrate to RuCl2(PPh3)3 amounting to 250:1 the conversion rate was much higher than that of the reaction performed with a double dose of the catalyst. Results of experiments also show that samples of the post-reaction solution should be analyzed right after the reaction, because even if they are stored in low temperature the amount of product can change up to 3–5% compared to the base sample and this change is not predictable. These findings have significant implications for further research of the reaction of homogeneous transfer hydrogenation of ketones. With the right catalysts and methods of their synthesis other parameters of this reaction can be optimized. The most important one is a change of solvent from isopropyl alcohol to a less toxic substance like water. This may increase the value of the reaction in green chemistry and chemical industry.

3

New long-term action insulin formulations obtained using polycations for heparin neutralization

Kamiński Kamil, Kaczor-Kamińska Marta, Irska Izabela, Popiołek Iwona, Szczubiałka Krzysztof, Nowakowska Maria

Bio-Algorithms and Med-Systems

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2019

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Vol. 15, no. 3

art. no. 20190029

EN

Phenomena that occur between an insulin and four different positively charged polymers (protamine, cationic dextran, chitosan, and poliallylamine derivatives) were studied by dynamic light scattering and fluorescence measurements (using fluorescein-labeled polymers). These processes were compared to the reaction of polycations with heparin that is responsible for the neutralization of anticoagulant activity in blood stream.The nature of polycations interaction with heparin is electrostatic, while the interaction with insulin is more complicated.We observed that the presence of zinc atoms (and its complexing by nitrogen from macromolecules) is critical for insulin suspensions formation and stability. The differences between the nature of these two reactions were revealed. The highly immunogenic action of protamine present in long-acting insulin products makes it reasonable to develop similar systems based on the nonprotein polycations.