The following paper presents application of methods of noise reduction in acoustic emission signals, accompanying phenomenon electrical treeing of solid dielectric such as epoxy resin, based on time-frequency signal analysis. For signal estimation was applied method of soft and hard thresholding described by Donoho and Johnson. All calculations ware obtained with use of Matlab software, especially Wavelet Toolbox.
PL
W artykule zaprezentowanie zastosowanie metod redukcji szumu w sygnałach emisji akustycznej towarzyszących zjawisku drzewienia dielektryków stałych, w szczególności żywic epoksydowych, opartych na falkowej analizie sygnałow. Opisany został algorytm usuwania szumów z sygnału m. in. algorytm miękkiego oraz twardego progowania stworzonych przez Donoho i Johnsona. Wszystkie obliczenia wykonano w Matlabie z wykorzystaniem dodatku Wavelet Toolbox.
Different groups of free radicals exist in biological material like animal tissues or plants parts. The processes like heating or cooling creates additional types of free radicals groups in this organic matter, due to changes in chemical bonds. The paper proposes a method to determine types and concentrations of different groups of free radicals in the matter processed in various temperatures. The method extracts the spectrum of free radicals using electron paramagnetic resonance with the microwave power of 2.2 mW. Then an automatic method to find a best possible fit using limited number of theoretical mathematical functions is proposed. The match is found using spectrum filtration, and a genetic algorithm implementation supported by a Gradient Method. The obtained results were compared against the samples prepared by an expert. Finally, some remarks were given and new possibilities for future research were proposed.
JavaScript jest wyłączony w Twojej przeglądarce internetowej. Włącz go, a następnie odśwież stronę, aby móc w pełni z niej korzystać.