|
| |
|
|
Synthesis and study of ceramide analogues
Školová, Barbora ; Vávrová, Kateřina (advisor) ; Matějka, Pavel (referee) ; Šklubalová, Zdeňka (referee)
Charles University in Prague, Faculty of Pharmacy in Hradec Králové Department of inorganic and organic chemistry Candidate: Mgr. Barbora Školová Supervisor: doc. PharmDr. Kateřina Vávrová, Ph.D. Title of doctoral thesis: Synthesis and study of ceramide analogues Ceramides (Cer) together with free fatty acids and cholesterol form intercellular lamellar space of the uppermost skin layer (stratum corneum, SC). This lipid matrix presents the proper skin barrier - it protects organism against outer environment and keeps its homeostasis as well. The composition and arrangement of the intercellular lipid matrix is essential for the skin barrier properties. In spite of this fact, the organization of SC lipids at the molecular level is not fully elucidated. The aim of this work is to contribute to more detailed insight into organization of skin barrier using SC lipid model membranes, in particular to find the structural parameters in ceramide molecules, which play a role in the maintenance of the skin barrier. The SC model membranes present a useful tool to study SC lipids, they mimic physiological or pathological conditions in the skin. The obtained results should be used in diagnosing or therapy of skin diseases characteristic with impaired barrier function, such as atopic dermatitis or psoriasis....
|
|
| |
|
| |
|
|
Emotion Detection from Speech
Popková, Anna ; Fér, Radek (referee) ; Matějka, Pavel (advisor)
This Bachelor Thesis deals with research in the field of emotion recognition mainly from speech and marginally from other modalities (video and physiological data). It closely describes the topology of the systems built specifically for the subject of this work. Moreover, it describes experiments leading to optimized pre-processing, regressor training and post-processing. Data used for these research origins from evaluation AV+EC 2015. Results of fusion systems producing the most precise prediction were sent to this evaluation. The Bottle-Neck features are newly tested and combined favorably with commonly used eGeMAPS features for the recognition of arousal. For valence, two kinds of video features are used. Muli-task system (recognizing both valence and arousal) using Bottle-Neck features produces competitive results and is only 13 % relatively behind the mentioned fusion system. This is especially appealing for applications where only audio is available.
|
|
|
Robust Speaker Verification
Profant, Ján ; Novotný, Ondřej (referee) ; Matějka, Pavel (advisor)
The goal of this paper is to analyze the impact of codec degraded speech on a state-ofthe-art speaker recognition system. Two feature extraction techniques are analyzed - Mel Frequency Cepstral Coefficients (MFCC) and the state-of-the-art system using Bottleneck features together with MFCC. Speaker recognition system is based on i-vector and Probabilistic Linear Discriminant Analysis (PLDA). We compared scenarios where PLDA is trained only on clean data, then system where we added also noise and reverberant data, and at last, codec degraded speech. We evaluated the systems on the matched conditions (data from the same codec are seen with PLDA) and also mismatched conditions (PLDA does not see any data from the tested codec). We experimented also with recently introduced technique for channel adaptation - Within-class Covariance Correction (WCC). We can see clear benefit of adding transcoded data to PLDA or WCC (with approximately same gain) for both tested conditions (matched and mismatched).
|
|
|
Internet Voice Search
Belobrad, Michal ; Matějka, Pavel (referee) ; Schwarz, Petr (advisor)
This thesis is concerned with creating applications for touchscreen phones with the operating system Bada. The objective of this application is to allow users to search the web using their voice. We introduce with Samsung Wave for which this application was developed. In addition we look at the results of the recognizer processing, auto-complete, and their combination.
|
|
|
Analysis of Telephone Call of Two People
Herceková, Monika ; Schwarz, Petr (referee) ; Matějka, Pavel (advisor)
This thesis deals with analysis of two people's phone call. It describes possible ways of speech and silence appearence in record and reasons criteria for listening the record. There is implemented prototype of application suggested in the thesis for analysis of telephone call. There are introduced possible extensions of the work at the end of the thesis.
|
|
|
Voice Activity Detection
Břenek, Roman ; Grézl, František (referee) ; Matějka, Pavel (advisor)
This thesis describes techniques for voice activity detection in audio recordings. It is necessary to correctly classify all non-speech segments and recognize speech with noisy background. The whole process of voice activity detection (VAD) is described in this thesis, i.e. digitizing audio signal, feature extraction, training of the system, post-processing and final evaluation. There are three different systems compared within the thesis . The first one is based on phoneme recognition using neural network, the other two are variations of Gaussian Mixture Models (GMM). Each system was tested on three data sets - Tactical Speaker Identification Speech Corpus (TSID), Ham Radio (HR) and Rich Transcription Evaluation (RT05-RT07). The best results of each system are compared with the results of the third side.
|
|
|
Computer Graphics and Video Features for Speaker Recognition
Fér, Radek ; Matějka, Pavel (referee) ; Černocký, Jan (advisor)
We describe a non-traditional method for speaker recognition that uses features and algorithms used mainly for computer vision. Important theoretical knowledge of computer recognition is summarized first. The Boosted Binary Features are described and explored as an already proposed method, that has roots in computer vision. This method is evaluated on standard speaker recognition databases TIMIT and NIST SRE 2010. Experimental results are given and compared to standard methods. Possible directions for future work are proposed at the end.
|
guest ::
