The aim of this thesis is creation the appropriate multimedia support for signals and system with continuous time. The understanding of this issue is very important, because the obligatory subject Signals and systems, exactly BSIS, is taught at the EST bachelor degree. The understanding is also necessary prerequisite to successful understanding next topics in other related subjects. The next part of this thesis is focused on one dimension discrete signals. Concretely, the aim of this part is a realization of software system. Designed system has some basic operations (the signal energy, the number of signal zero crossing etc.) with sound files and also some advance functions e.g. vowel seeking and separating in fluent speech. The system is divided into two main parts. The first one analyzes sound files, creates the new sound file with wanted vowel and matrices with important parameters for other processing. The second program computes with given data, which statistically evaluates in other steps. The final system can be useful for speaker recognition, his emotional status etc.

A brief introduction into biometrics is described in this thesis leading to description and to design a solution of verification system using speech analysis. The designed system provides firstly basic signal processing, then vowel recognition in fluent Czech speech. For each found vowel, observed speech features are calculated. The created GUI application was tested on created speaker database and its efficiency is approximately 54 % for short testing utterances, and approx. 88 % for long testing utterances respectively.

The purpose of this thesis is to design and implementation of the control unit for DC motors. Design is based on the concept of universal communication interface, which has been designed for simplification of communication between individual control systems. Control unit has been realized for DC motors within supply voltage range from 6 to 48 V, and maximal continuous current 2,5 A. For realization, we have used microcontroller LPC2103, and full bridge driver TLE 6209. In the thesis, we have described particular developmental steps of the control unit.

Cyclooxygenase-2 (COX-2) is a prostaglandin-generating enzyme that exhibits low basal expression levels and is upregulated in the central nervous system (CNS) in response to inflammatory stimuli. COX-2 has been implicated in the microglial-mediated neuroinflammatory and neurodegenerative processes of multiple sclerosis (MS), a demyelinating autoimmune disease. To study COX-2 activity and the role it may play in demyelination, a novel PET radiotracer specific for COX-2, [11C]BRD1158, was developed and evaluated in the lysolecithin rodent model of focal demyelination with PET-MR imaging. Preliminary results of this pilot pre-clinical study confirmed our hypothesis that the properties of [11C]BRD1158 enable visualization and monitoring of COX-2 activity under pathological conditions induced by LPC. Radiotracer uptake correlated positively with disease progression at the site of LPC injection in male rats, peaking at day 7 and resolving by day 28. Treatment with an FDA-approved MS therapy, Siponimod, diminished the increase in COX-2 activity and tracer uptake at the lesion site and throughout the brain in both male and female rats. The results from the present study will inform future pre-clinical and translational work that validates the use of [11C]BRD1158 to image COX-2 activity as a marker of underlying inflammation in MS, leading to a better understanding of pathological and inflammatory processes in MS development and progression.

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This dissertation thesis deals with a new method for digital modulation recognition. The history and present state of the topic is summarized in the introduction. Present methods together with their characteristic properties are described. The recognition by means of artificial neural is presented in more detail. After setting the objective of the dissertation thesis, the digital modulations that were chosen for recognition are described theoretically. The modulations FSK, MSK, BPSK, QPSK, and QAM-16 are concerned. These modulations are mostly used in modern communication systems. The method designed is based on the analysis of module and phase spectrograms of the modulated signals. Their histograms are used for the examination of the spectrogram properties. They provide information on the count of carrier frequencies in the signal, which is used for the FSK and MSK recognition, and on the count of phase states on which the BPSK, QPSK, and QAM-16 are classified. The spectrograms in that the characteristic attributes of the modulations are visible are obtained with the segment length equal to the symbol length. It was found that it is possible to correctly recognize the modulation with the known symbol length at the signal-to-noise ratio at least 0 dB. That is why it is necessary to detect the symbol length prior to the spectrogram calculation. Four methods were designed for this purpose: autocorrelation function, cepstrum analysis, wavelet transform, and LPC coefficients. These methods were algorithmized and analyzed with signals disturbed by the white Gaussian noise, phase noise and with signals passed through a multipass fading channel. The method of detection by means of cepstrum analysis proved the most suitable and reliable. Finally the new method for digital modulation recognition was verified with signals passed through a channel with properties close to the real one.

La LPC ou Cued Speech est un augment manuel qui permet au sourd de désambiguïser l'information phonologique visible sur le visage. L'efficacité de ce système pour l'acquisition de la phonologie de la langue est bien établie. Mais la production du code LPC n'avait jamais été étudiée, et nous l'avons fait par une technique de suivi des mouvements labiaux et manuels de quatre codeuses professionnelles. Notre résultat comportemental majeur est que le geste de la main - contre toute attente - précède le geste des lèvres. Cette anticipation donne un rôle inattendu à la parole visible: celui de venir désambiguïser le geste manuel, conçu au départ pour désambiguïser la parole... Notre hypothèse est que le système de Cornett a été recodé en termes neuralement compatibles pourle contrôle des gestes des voyelles et des consonnes dans la LPC et la parole. Ainsi le contrôle des contavts vocaliques manuels va se trouver en phase avec celui des contacts consonantiques visibles. Ce phasage est assez précis pour que, quelles que soient les variations de la durée de l aproduction de la syllabe CV, l'aboutissement de la détente (stroke) du système main-bras se produise dans la phase de tenue de l'attaque consonantique. L'icorporation de la main et de la face dans un espace de contrôle neural commun peut être ainsi pleinement réalisée dans la LPC.

La Langue Française Parlée Complétée (LPC) héritée du Cued Speech (CS) a été conçue pour compléter la lecture labiale par nature ambigüe et ainsi améliorer la perception de la parole par les sourds profonds. Dans ce système, le locuteur pointe des positions précises sur le côté de son visage ou à la base du cou en présentant de dos des formes de main bien définies. La main et les lèvres portent chacune une partie complémentaire de l'information phonétique. Cette thèse présente tout d'abord une modélisation du flux manuel pour le codage automatique des positions de la main et de la configuration. Puis les travaux sont centrés sur le flux labial en discutant la classification des voyelles et des consonnes du Français. Le flux labial est composé des variations temporelles de paramètres caractéristiques issus du contour interne et externe des lèvres. Dans le cas des voyelles la méthode de classification utilise la modélisation gaussienne et les résultats montrent une performance moyenne de 89 % en fonction de la position de la main LPC. Le contexte vocalique est pris en compte dans le cas des consonnes par une modélisation HMM de la transition labiale de la consonne vers la voyelle avec un taux d'identification de 80 % en termes de visèmes CV. Un modèle de fusion « Maître-Esclave » piloté par le flux manuel est présenté et discuté dans le cadre de la reconnaissance des voyelles et des consonnes produites en contexte LPC. Le modèle de fusion prend en compte les contraintes temporelles de la production et la perception du LPC, ce qui constitue aussi une première contribution à la modélisation du système LPC du point de vue perceptif.

A Mandarin phrase recognition system based on MFCC, LPC scaled excitation, vowel model, hidden Markov model (HMM) and Viterbi algorithm is proposed in this thesis. HMM, which is broadly used in speech recognition at present, is adopted in the main structure of recognition. In order to speed up the recognition time, we take advantage of stability of vowels in Mandarin and incorporate with vowel class recognition in our system. For the speaker-dependent case, a single Mandarin phrase recognition can be accomplished within 1 seconds on average in the laboratory environment.

Cette thèse traite de la mise en œuvre d'un système de synthèse 3D de parole audiovisuelle capable, a partir d'une simple chaîne phonétique, de générer un signal audio synthétique, les mouvements du visage correspondant ainsi que les mouvements de la main reproduisant les gestes de la Langue française Parlée Complétée (LPC). Nous avons enregistré les mouvements faciaux et manuels d'une codeuse LPC par une technique de motion capture, ainsi que le signal audio correspondant, lors de la production d'un corpus de 238 phrases couvrant l'ensemble des diphones du français. Après traitements et analyses des données, nous avons implémenté un système de synthèse par concaténation d'unités en deux étapes capable de générer de la parole codée. Enfin, nous avons évalué notre système tant au niveau de l'intelligibilité segmentale qu'au niveau de la compréhension. Les résultats sont prometteurs et montrent clairement un apport d'information du code de synthèse.