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Compensatory Vocal Folds for Source Voice Generation: Computational Modeling of Vocal Folds Function
Matug, Michal ; Vampola, Tomáš (referee) ; Horáček, Jaromír (referee) ; Švancara, Pavel (advisor)
This doctoral thesis focuses on computational modelling of human vocal folds and vocal tract functions using finite element method (FEM). Human voice is crucial in human communication. Therefore one of the main targets of current medicine is creation of artificial vocal folds, which would substitute the original vocal folds. The computational modelling can be used to understand principles of voice production, determination of parameters that the artificial vocal folds have to meet and verification of their functionality. First part of this thesis focuses on modelling of human voice creation by whisper. Influence of intraglottal gap on eigenvalues distribution for individual vowels was analysed using FEM vocal tract and trachea model. Further there is presented two-dimensional (2D) finite element model of the flow-induced self-oscillation of the human vocal folds in interaction with acoustic spaces of the vocal tract. The 2D vocal tract model was created on the basis of converting the data from magnetic resonance images (MRI). Explicit coupling scheme with separated solvers for structure and fluid domain was used for modelling of the fluid-structure interaction. Created computational model comprises: large deformations of the vocal folds tissue, contact between vocal folds, fluid-structure interaction, morphing the fluid mesh according to the vocal-fold motion (Arbitrary Lagrangian-Eulerian approach), unsteady viscous compressible or incompressible airflow described by the Navier-Stokes equations and airflow separation during glottis closure. This model is used to analyse the influence of stiffness and damping changes in individual vocal fold tissue layers (in particular in superficial lamina propria). Part of this computational analysis is also comparison of vocal folds behaviour for compressible and incompressible flow model. Videokymograms (VKG) are subsequently created from obtained results of FEM calculations which enable to compare individual variants between themselves and with motion of real human vocal folds. In next part of this thesis is presented three-dimensional (3D) finite element model of the flow-induced self-oscillation of the human vocal folds. This 3D model was created from a previous 2D model by extrude to the third direction. Using this model was again compared influence of compressible and incompressible flow model on vocal folds motion and generated sound by using videokymograms and acoustic spectra. The last part of this thesis focuses on the possibility to replace missing natural source voice in form reed-based element. Behaviour of reed-based element was analysed using computational modelling and using measurements on experimental physical model. The physical model enables changes in setting gap between reed and reed stop and performing acoustical and optical measurements.
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GSM Module for Wireless Sensor Networks
Mayer, Jan ; Janoušek, Vladimír (referee) ; Horáček, Jan (advisor)
Main goal of this project is to achieve communication between user and distant wireless sensor network using GSM technology. This task will be accomplished by connecting Crossbow Iris wireless sensor node and Teltonika GSM module device. Communication itself will be provided by sending/receiving SMS and connecting platform to remote server over the internet using GPRS technology.
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Truck Braking System
Horáček, Jonáš ; Hejtmánek, Petr (referee) ; Blaťák, Ondřej (advisor)
The aim of this bachelor thesis is to examine truck braking systems and their components due to the construction and to describe their cooperation. The first part deals with brake definition and with dividing brakes into different categories. The second part focuses on compressed air brakes, truck trailer brakes and retarders. The thesis has a research character and the last part deals with possible trends in the development of truck braking systems.
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In Orderto Turn Attention to the Significance of the Monuments. The Image of Monument Conservation in Bohemia in the Period after the Establishment of the Central Commission
Horáček, Jaroslav ; Konečný, Lubomír (advisor) ; Petrasová, Taťána (referee) ; Novotný, Michal (referee)
e founding and subsequent convening of the Central Commission for the Preservation and Research of Building Monuments (k. k. Central-Commission zur Erforschung und Erhaltung der Baudenkmale) in 1850/1853 represents a significant milestone in the history of monument conservation in the countries of the Habsburg Monarchy and has its place in Europe. e present dissertation traces the impact of the Central Commission's activities in Bohemia during the 1850s and early 1860s, which roughly corresponds to the time of K. Czoernig von Czoernhausen's presidency. In the introduction, attention is paid to a review of current texts on early conservation, their authors and the method of treatment of the topic. en the situation of the preservation of monuments in selected neighbouring and more distant European states (Baden, Württemberg, Prussia, Saxony, Styria, France) is outlined. e beginning of the Central Commission is connected with the recruitment and designation of conservators and correspondents to work at the sites. According to the files of the Presidium of the Bohemian Governorate, the process from the selection of candidates to their designation in 1854 has been carefully described. In the following years, the individual regional conservators and later the correspondents contributed, according to their...
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One-trial association task as a basic biological model of episodic memory in rats
Radostová, Dominika ; Stuchlík, Aleš (advisor) ; Horáček, Jiří (referee) ; Telenský, Petr (referee)
One-trial association task as a basic biological model of episodic memory in rats Abstract A very important structure in the animal and human brain is the hippocampus. The study one of its many functions, episodic memory, is facing with the limited possibilities of non-invasive methods. In this regard, animal models are helpful. In order to study the individual components of such a complex ability in detail, a new behavioral task testing the association of temporally close but separate stimuli was developed. The test animals were exposed to a sequence of a sound conditioned stimulus and an unconditioned electric shock, between which there was a delay of 2 seconds. 59% of the rats successfully learned the association as well as the correct escape reaction to solve the task. Based on the results, the so-called One-Trial Trace Escape Reaction task could be a very valuable tool for a more detailed understanding of animals' incidental one-trial learning important for episodic memory. Another important phenomenon investigated in this work is the development of new neurons in the hippocampus in adulthood and its influence on learning and flexibility. After blocking the animals' neurogenesis with the temozolomide, the animals' ability to learn to avoid an invisible sector in the active avoidance task was tested....
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Finite element modal analysis of a silicone vocal fold filled with fluid
Hájek, P. ; Radolf, Vojtěch ; Horáček, Jaromír ; Švec, J. G.
A three dimensional (3D) finite element (FE) model of a silicone vocal fold (VF) filled with fluid is presented here. The silicone part of the model is based on partial differential equations of the continuum mechanics and consider large deformations. The fluid domain encapsulated in the silicone VF is defined semianalytically as a lumped-element model describing the fluid in hydrostatic conditions. The elongated and pressurized silicone VF was subjected to perturbed modal analysis. Results showed that the choice of the fluid inside the VF substantially influences the natural frequencies. Namely, the water-filling lowers the natural frequencies approximately by half over the air-filling. Besides, the procedure of reverse engineering for obtaining the geometry of the VF from already 3D-printed mold is introduced.
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Prediction of the Antidepressant Effect of Ketamine Based on Clinical Parameters and Intoxication Phenomenology
Andrashko, Veronika ; Horáček, Jiří (advisor) ; Papežová, Hana (referee) ; Juřica, Jan (referee)
Background: ketamine is a rapid and potent antidepressant treatment, however no sufficient predictors for tailored treatment have been identified to date. The aim of the thesis was to identify possible clinical and phenomenological characteristics, associated with better antidepressant response in patients receiving ketamine. Materials and methods: data from 86 depressed patients from cohorts A (2010-2015) and B (2018-2022) were utilized. All patients underwent ketamine infusion and demographic as well as clinical assessment (severity of depressive symptoms, subjective and objective anxiety and anhedonia before and after ketamine application). In addition, an electrocardiogram was taken to assess heart rate variability in cohort A and blood pressure, heart rate, and altered state of consciousness scales were recorded in cohort B during ketamine intoxication. Results: in cohort A, the use of higher doses of benzodiazepines was associated with worse response at day 3 (p = 0.04) and day 7 (p = 0.02) after ketamine administration. Responders showed higher heart rate (p = 0.001) and differed from nonresponders in heart rate variability (p = 0.011). In cohort B, responders reached higher values od systolic (p = 0.003) and diastolic (p = 0.005) blood pressure during intoxication, but not higher heart...
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Altered morphology of white and grey matter in patients with Alzheimer disease and Schizophrenia on MRI
Lahutsina, Anastasiya ; Zach, Petr (advisor) ; Horáček, Jiří (referee) ; Němcová, Veronika (referee)
Cortical folding of the anterior cingulate cortex (ACC), particularly the cingulate (CS) and the paracingulate (PCS) sulci, represents a neurodevelopmental marker. Deviations in in utero development in schizophrenia can be traced using CS and PCS morphometry. In the present study, we measured the length of CS, PCS, and their segments on T1 MRI scans in 93 patients with first episode schizophrenia and 42 healthy controls. Besides the length, the frequency and the left-right asymmetry of CS/PCS were compared in patients and controls. Distribution of the CS and PCS morphotypes in patients was different from controls. Parcellated sulcal pattern CS3a in the left hemisphere was longer in patients (53.8 ± 25.7 mm vs. 32.7 ± 19.4 mm in controls, p < 0.05), while in CS3c it was reversed-longer in controls (52.5 ± 22.5 mm as opposed to 36.2 ± 12.9 mm, n.s. in patients). Non parcellated PCS in the right hemisphere were longer in patients compared to controls (19.4 ± 10.2 mm vs. 12.1 ± 12.4 mm, p < 0.001). Therefore, concurrent presence of PCS1 and CS1 in the left hemisphere and to some extent in the right hemisphere may be suggestive of a higher probability of schizophrenia. Measurement of an hippocampal area or volume is useful in clinical practice as a supportive aid for diagnosis of Alzheimer's disease....
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Robust semi-generalized camera pose estimation using multiple minimal solvers
Beliansky, Patrik ; Kúkelová, Zuzana (advisor) ; Horáček, Jan (referee)
Camera pose estimation is a fundamental problem in computer vision with various ap- plications, such as in Structure-from-Motion and Visual Localization. These applications often focus on registering a new camera to a set of already registered cameras with known poses. Thus, camera poses can be estimated by solving the semi-generalized relative pose problem. This is usually achieved by using a minimal solver inside a RANSAC-style robust estimator. This estimator can handle data with a large amount of outliers. While solvers for the semi-generalized relative pose problem are typically too inefficient for practical use, the highly related semi-generalized homography problem can be solved effi- ciently. This thesis develops and investigates different implementations, e.g., using Sturm sequences or companion matrix approaches, for multiple solvers for this problem. This thesis further proposes a novel RANSAC-based approach that automatically selects the most suitable solver for each iteration in a data-driven way. In detailed experiments, the solvers are evaluated in terms of efficiency and stability. Extensive experiments show the effectiveness of our novel RANSAC-based approach by comparing it against two baselines. 1
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