Wyniki wyszukiwania - Biblioteka Nauki

1

Wyznaczanie składowych mocy z wykorzystaniem funkcji korelacji

100%

Górniak M.

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tom R. 56, nr 5

464-470

PL

W artykule przedstawiono sposób wyznaczania składowych mocy według podejścia zaproponowanego przez Hashada i Hartmana. Dla porównania wyników uzyskanych tym sposobem, zastosowano definicje mocy zalecane przez standard IEEE 1459-2000. Badania były wykonywane pod kątem wykorzystania cyfrowego przetwarzania sygnałów do określania parametrów mocy. Przeprowadzono je dla przebiegów sinusoidalnych i okresowych niesinusoidalnych. Zastosowano wyznaczanie mocy zgodne ze standardem IEEE: na podstawie wartości chwilowych, według Budeanu oraz Depenbrocka. Do wyznaczania mocy według podejścia Hashada i Hartmana napisany został program w języku C++ "Funkcje" oraz arkusz obliczeniowy w programie Excel. W pracy przedstawiono wyniki badań symulacyjnych.

EN

A comparison of determination methods of power parameters by Hashad and Hartman way and by recommendation of IEEE 1459?2000 standard, in order to make the use digital signal proc-essing for describing the power components there are presented in the paper. Hashad and Hartman power functions properties are described in Chapter 2. In the paper a determination of power according to IEEE standard was applied: on the basis of instantane-ous values, by Budeanu way and by Depenbrock way. The formulas are described in Chapter 3. For calculation of power by Hashad and Hartman way program in C++ language called "Funkcje" and spread-sheet of Excel program were created. Thanks to the written software the comparison and evaluation of Hashad and Hartman way with actually valid IEEE 1459-2000 standard methods were carried out. The comparison and evaluation with use of sinusoidal and periodic non-sinusoidal waveforms were made up. The examples of voltage and current simulation waveforms are shown on Figures 2, 4 and on Figures 3, 5 appropriate to them functions of power waveforms. The most important results of re-search and intermediate conclusions are presented in Chapter 5, in Tables 1 to 6 and on Figures 6 to 8. The main conclusions and future direction of the work are pointed out in Chapter 6.

2

The preparation of aramid fibres in silicone based composite materials

51%

Dobrzański L. A. , Nowak A. J. , Pusz A. , Górniak M.

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tom Vol. 45, nr 2

125--131

EN

Purpose: The evaluation of modified aramid fibres - Kevlar - as reinforcement in silicon materials used in medicine. Design/methodology/approach: Samples of laminated material based on modified aramid fibres and medical silicone were made by a method of manual formation of laminates that is impregnation of reinforcement with matrix to hardening silicone process using hardening methods connected with heat. Created material was observed on Scanning Electron Microscopy manufactured by Zeiss. Findings: The results show that the modification of aramid fibres has a positive influence on adhesion of silicon material to aramid fibres and strengthening of tested samples. Research limitations/implications: Carried out investigations show that the problem with modification of aramid fibres is very important in having proper percentage of intensifier in developed material used for medical purposes. Originality/value: Taking the specific properties of material into account it seems that modification of aramid fibres would be useful in medicine. However, application of aramid fibres as reinforcing phase of polymer medical materials requires many additional investigations which are already planned and will soon be done in Institute of Engineering Materials and Biomaterials at Silesian University of Technology.

3

Czujniki i przetworniki pomiarowe w sieci przemysłowej M2 M

51%

Górniak M. , Krywald K. , Masnicki R.

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tom Vol. 49, nr 6

112-114

PL

W artykule omówiono podstawowe właściwości sieci bezprzewodowej ZigBee. Opisano konfiguracje urządzeń sieciowych firmy MeshNetics. Przedstawiono sposoby łączenia peryferii urządzenia końcowego ZigBee z przykładowymi wykonaniami przetworników pomiarowych.

EN

In paper, the basic features of ZigBee wireless network were discussed. The configuration of MeshNetics network devices were described. The ZigBee end-device peripherals connections to the exemplary measurement converters were shown.

4

Effect of water dilution and alcohol mixing on erosive potential of orange juice on bovine enamel

45%

Malara L. , Kloc-Ptaszna A. , Dobrzański L. , Górniak M. , Stefański T.

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tom Vol. 62, nr 1

15--21

EN

Purpose: This in vitro study aimed to evaluate the changes of erosive potential of an orange juice before and after mixing with water and alcohol. Design/methodology/approach: Fifty enamel specimens obtained from bovine teeth were prepared and randomly assigned into the following groups (n=10) with different erosive solution: I. commercially available pure orange juice (Cappy, Coca Cola Co.), II. orange juice diluted with distilled water at a ratio 3:1 (v/v), III. orange juice mixed with vodka (Smirnoff, 40% ethanol, Polmos) at a ratio 3:1 (v/v); IV. Orange juice diluted with distilled water (1:1, v/v), V. Orange juice mixed with vodka (1:1 v/v). The enamel specimens were submitted to a short-term erosion-remineralization cycling model (five 1-min erosion challenges in-between six 10-min remineralization periods in artificial saliva). Erosive potential of the drinks was assessed on the basis of chemical analysis and percent surface microhardness change (%SMHC) calculated from Vickers surface microhardness measurements before and after cycling. In chemical analysis of the experimental drinks, the pH value, titratable acidity, and buffer capacity (β) were determined. Findings: The pH of tested drink remained low even after dilution with water or mixing with alcohol, however, titratable acidity decreased after addition of water and alcohol. Short-term erosion-remineralization cycling resulted in significantly decreased surface microhardness of enamel specimens in all experimental groups. In the proportion of 3:1, juice mixed with alcohol resulted in significantly smaller %SMHC than juice diluted with water. This difference was not observed at a ratio 1:1. Practical implications: Consumers should be aware of tooth damage by drinks with low pH and high titratable acidity, even when mixing them with water and alcohol. Originality/value: To the best of our knowledge, this is the first study comparing the erosive effect of water-diluted orange juice with that of juice mixed with alcohol.