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Measurement of relaxation constants, using MR techniques
Pavlíček, Petr ; Chmelař, Milan (referee) ; Gescheidtová, Eva (advisor)
Bachelor‘s thesis deals with measuring methods of relaxation times T1 and T2 using nuclear magnetic resonance (NMR) and experimental measuring of conductive gels samples. In the theoretical part an analysis of the behavior of atoms placed in the magnetic field, basic principles of NMR functionality and commonly used measuring sequences for relaxation times detection are given. The experimental part is oriented to measuring both relaxation times of conductive gels samples, which were examined in terms of use in lithium-polymer (Li-Pol) accumulators. Relaxation times T1 were measured using Inversion Recovery (IR) method and relaxation time T2 using Hahn Echo and halfwidth methods.
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A System Using Artificial Intelligence to Detect Starlings
Heimlichová, Klára ; Gescheidtová, Eva (referee) ; Marcoň, Petr (advisor)
This thesis describes the usage of artificial intelligence for the purpose of acoustical detection of starlings. Repelling the birds based on acoustical detection is an efficient method, although it can be disrupted by e.g. sounds of loud motors of cars passing or by other birds. This project is created in order to effectively protect ripe fruits growing on vineyards using remotely controlled sound contraption. First part of this thesis contemplates the principles of capturing sound and the analysis and classification of sound recordings. The second part describes the concept of the detection module itself, its construction and results of testing used materials.
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Processing of images of early spruce needles scanned by MR technology
Raichl, Jaroslav ; Říha, Kamil (referee) ; Gescheidtová, Eva (advisor)
This semester project deals with filtering of the images detected by use of NMR obtained by NMR application measurement of nuclear magnetic resonance (NMR). This thesis includes the theory of nuclear magnetic resonance, digital filters, basic digital filter banks structures, theory of Wavelet transformation and description of Signal to Noise Ratio calculation. Basic procedure of the MR signal denoising is summarized in the theoretical part of the thesis. The denoising of the images detected by nuclear magnetic resonance is described. In experimental part filtering methods for images denoising are described, which are implemented in program Matlab. These methods are based on Wavelet transformation, digital filter banks with proper thresholding. Effectiveness of filtering methods designed was verified on 2D NMR images. All of these 2D images were measure on MR tomography in the Institute of Scientific Instruments Academy of Science of the Czech Republic in Brno.
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Fast MRI methods
Kořínek, Radim ; Gescheidtová, Eva (referee) ; Bartušek, Karel (advisor)
This thesis deals with comparison of rapid and conventional methods used in MRI (Magnetic Resonance Imaging). There is a description of imaging methods such as EPI (Echo Planar Imaging), Ultra-fast GRE, FSE (Fast spin echo) as well as a snapshot-FLASH and FISP (Fast Imaging with Steady Precession). Experimental part of this thesis deals with the rapid FSE (Fast Spin Echo) method. Especially is explained and assembled an algorithm for proper compilation of data from the FSE method. This algorithm allows us to evaluate the images from the FSE method. This method is examined in detail (in terms of impact parameters) and compared with traditional conventional methods. Finally, the individual images are evaluated, and the best parameters for FSE method are identified.
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A System Using Artificial Intelligence to Detect Starlings
Heimlichová, Klára ; Gescheidtová, Eva (referee) ; Marcoň, Petr (advisor)
This thesis describes the usage of artificial intelligence for the purpose of acoustical detection of starlings. Repelling the birds based on acoustical detection is an efficient method, although it can be disrupted by e.g. sounds of loud motors of cars passing or by other birds. This project is created in order to effectively protect ripe fruits growing on vineyards using remotely controlled sound contraption. First part of this thesis contemplates the principles of capturing sound and the analysis and classification of sound recordings. The second part describes the concept of the detection module itself, its construction and results of testing used materials.
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RF coil for MR systém
Vojtíšek, Miloš ; Kořínek, Radim (referee) ; Gescheidtová, Eva (advisor)
The bachelor thesis is focused on radio frequency coils for magnetic resonance imaging systems. Magnetic resonance is used for imaging of many objects, especially human body in medicine, plants and many other different objects. For obtaining optimal results it is essential to use a special suitable coil for every single application. In the first part of this work, the short overview of principles of magnetic resonance imaging is described followed by a look at hardware used in MRI. The main aim of the work is design of several different types of RF coils used in MRI. Finally two suitable designs have been chosen for the purpose. Coils have been realized, tested in experiments. Results were analyzed, maps of generated magnetic field were calculated and homogeneity was determined.
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Filtering methods for NMR measurements
Zvěřina, Lukáš ; Rajmic, Pavel (referee) ; Gescheidtová, Eva (advisor)
The subject of this thesis is the principle of modern filtering techniques of signals acquired by nuclear magnetic resonance technique. In the NMR images a disturbing element is almost always present, especially noise, which causes useful signal and image degradation. The noise is a random signal, related to the errors of measurement and evaluation. The noise brings no information about the behaviour of the signal and it is unwanted signal component. The bachelor thesis is therefore focused mainly on the removal of the interfering parts of the signals. It exploits the fact that the nowadays widely expanding wavelet transform is closely connected with the banks of the digital filters. The subsequent section deals with experimental filtering of signals by implementation the wavelet transform in Matlab.
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Segmentation Methods in Biomedical Image Processing
Mikulka, Jan ; Přibil, Jiří (referee) ; Dostál, Otto (referee) ; Gescheidtová, Eva (advisor)
The PhD thesis deals with modern methods of image processing, especially image segmentation, classification and evaluation of parameters. It is focused primarily on processing medical images of soft tissues obtained by magnetic resonance tomography (MR) and microscopic images of tissues. It is easy to describe edges of the sought objects using of segmented images. The edges found can be useful for further processing of monitored object such as calculating the perimeter, surface and volume evaluation or even three-dimensional shape reconstruction. The proposed solutions can be used for the classification of healthy/unhealthy tissues in MR or other imaging. Application examples of the proposed segmentation methods are shown in this thesis. Research in the area of image segmentation is focused on methods based on solving partial differential equations. This is a modern method for image processing, often called the active contour method. It is of great advantage in the segmentation of real images degraded by noise with fuzzy edges and transitions between objects. The results of the thesis are methods proposed for automatic image segmentation and classification.
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Study of gel electrolytes properties by MR methods
Mrnka, Michal ; Gescheidtová, Eva (referee) ; Bartušek, Karel (advisor)
Theoretical part of the work deals with explanation of nuclear magnetic resonance phenomenon, relaxation processes in system of nuclear spins, basic techniques for measurement of relaxation times. There are described diffusion and techniques for diffusion coefficient measurement including method for suppressing the background gradient. Experimental part describes preparation of gel electrolytes samples and measurement of relaxation times. Sodium salt was used as a conductive agent. There is interpreted dependence of relaxation times on polymerization times and on concentration of conductive agent in gels.
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