|
|
Mathematical transformation in dielectric relaxation spectroscopy
Brida, Marek ; Rozsívalová, Zdenka (referee) ; Frk, Martin (advisor)
This labor treats the problem of dielectric relaxation spectroscopy in time domain, measurement of the absorption characteristics and their conversion to the frequency domain by creating a frequency depends of loss factor. Paper reports an overview of the most common mathematical transformation and approximation, which are used for this conversion and they also compare some of them. Mathematical methods used in this paper are Fourier transformation and Hamon approximation. Measured dielectric insulation is slot insulation type Isonom NKN 2039 and Isonom NMN 0967.
|
|
|
Arc Fault Detection
Fendrychová, Michaela ; Chumak,, Oleksiy (referee) ; Orságová, Jaroslava (advisor)
Diplomová práce je zaměřena na problematiku analýzy signálů za účelem detekce poruchového oblouku, přičemž analýza signálů je prováděna v časové, frekvenční a smíšené časově-frekvenční oblasti. Práce stručně shrnuje existující normy pro zařízení pro detekci poruchového oblouku. Práce dokumentuje testy a měření, které byly realizovány v souladu s normami IEC 62606:2013 a UL 1699B. Z důvodu nedostatečnosti stávajících norem je v práci popsána nová metoda iniciace poruchového oblouku. naměřená data byla analyzována s využitím rychlé Fourierovy transformace, krátkodobé Fourierovy transformace a vlnkové transformace. Na základě provedeného literárního průzkumu a s využitím výsledků provedených analýz signálu je v práci proveden návrh nové detekční metody pro účely detekce poruchového oblouku v systémech napájených střídavým i stejnosměrným napětím.
|
|
|
Modification of Speech Rate
Kovářík, Aleš ; Schwarz, Petr (referee) ; Szőke, Igor (advisor)
This diploma thesis discusses modification of a speech rate. The PSOLA (Pitch Synchronous OverLap Add) method was used for the rate modification. This algorithm works in time domain. Another method -- phase vocoder, which works in frequency domain is also presented in an overview. This thesis extends the PSOLA method with a phoneme recognition, which allows for better understandability of the speech output by considering characteristics of the phonemes beeing pronounced. To examine this proposed method, an application connecting PSOLA and a phoneme recognizer was developed.
|
|
| |
|
|
Integral quality criteria of regulation
Gruna, Jiří ; Cejpek, Zdeněk (referee) ; Dosoudilová, Monika (advisor)
This bachelor’s thesis deals with the assessment of the quality of regulation using integral criteria. In the first part we are interested in the basic theory of regulation needed to understand the problem. It includes a description of the control system, differential equations in the theory of transfer function, types of regulators and addresses the question of stability. In the second part the thesis introduces the integral criteria. Using their area, we assess the quality of regulation. For clarity, the criteria are supplemented by examples to show their advantages and disadvantages.
|
|
|
Time domain edge finite elements
Cigánek, Jan ; Motl, Milan (referee) ; Raida, Zbyněk (advisor)
Diplomová práce se zabývá metodou hybridních (hranových a uzlových) konečných prvků ve frekvenční i časové oblasti. Tato metoda je použita pro analýzu vlnovodu parallel-plate, v kterém jsou umístěny dvě dielektrické vrstvy. Jako ukončení vlnovodu je implementována dokonale přizpůsobená vrstva označována PML. Projekt řeší možný výběr PML vrstvy v časové oblasti. Metoda je programována v programu MATLAB a výsledky jsou porovnány s programem COMSOL Multiphysics.
|
|
| |
|
|
Analysis of Heart Rate Variability
Škrtel, Karol ; Kolářová, Jana (referee) ; Provazník, Ivo (advisor)
The project describes the methods useful for observe changes of heart rate in ECG signal. Heart rate variability become (HRV) the conventionally accepted term to describe variations of NN intervals between consecutive heart beats and generally it is function of instantaneous heart rate or NN interval on time. HRV may be evaluated by time domain or frequency domain measures. In Matlab was developed algorithm, realized like function, which counts HRV parameters from ECG signal series. Analysis in time domain adverts to high correlation between statistic and geometric parameters and similarly with signal HRV. Results of frequency domain analysis shows similarity of power spectral density, which was calculated by two different ways (from interpolated and no interpolated signal HRV). Functionality of developed algorithm was verified on each signal. Project results have signification in progress of analysis ECG signal methods with a view to observe pathological changes in heart rate.
|
|
|
Detection of Gunshots from Small Arms
Nesvadba, Ondřej
This paper deals with acoustic gunshot detectionfrom small arms primarily for use in urban areas. Key part of thepaper is an examination of typical features of gunshot signals.Based on the short-term features detection algorithms areproposed in the time and frequency domains. Training andevaluation of the algorithms was performed using real gunshots,non-gunshots as well as synthetic gunshots. The non-gunshots setcontains impulsive acoustic events such as dog barking, glassbreaking, car horn, etc.
|
|
|
Detection of gunshots from small arms
Nesvadba, Ondřej ; Malucha, Jan (referee) ; Sigmund, Milan (advisor)
This thesis deals with acoustical gunshot detection from small arms, typically of the calibre up to 10 mm, primarily in urban areas. Thesis includes initial research of methods, which are usually used for gunshot detection. The key part of this work is examination of typical values of gunshot signal. Based on the values obtained, decisive parameters in time and frequency domains are determined and detection algorithms are proposed. Function of these algorithms is tested and evaluated. The possible influence of various features of recordings on detection success rate was discussed.
|
guest ::
