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Measurement and analysis of the blood flow in peripheral vessels by ultrasound Doppler methods
Lepš, Milan ; Sedlář, Martin (referee) ; Vlk, Daniel (advisor)
Nowadays, the Doppler ultrasonography is an essential part in medicine. With it, we can observe acoustic showoff some tissue associated with Doppler measurement of blood flow parameters. It is still using Doppler devices with a continuous signal which are although structurally and technically simpler, but they are suitable for measuring the speed and volume of blood flow in peripheral blood vessels of the upper and lower limbs. There are calculated physiological parameters from the flow curves that are clinically used for assessing the state of blood supply to the body part. We can determine many values from the flow curves, like peripheral resistance, blood flow in systole and diastole, medium speed, etc. Study group of people are male and female students from 18 to 20 years. Doppler measurements have been performed before physical exercise and after physical exercise.
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ASSESSMENT OF REINFORCED CONCRETE STRUCTURES EXPOSED TO ELEVATED TEMPERATURES
Rozsypalová, Iva ; Kolář,, Karel (referee) ; Vítek,, Jan (referee) ; Daněk, Petr (advisor)
Doctoral thesis is focused on the assessment of concrete structures after fire exposure and extends the knowledge in view of the main aims of the research defined in the objectives of his work. Thanks to the performed fire tests of full-scale concrete specimens, material characteristics corresponding to actual fire load have been assessed for different temperature levels. Resulting from presented research, main steps of assessment procedure have been recommended for both destructive and non-destructive tests of concrete after exposure to fire. Furthermore, behaviour of FRP reinforcement at elevated temperatures have been investigated. Aiming to determine the effects of fire exposure on reinforced concrete structures, experimental program have been defined and performed, including concrete beams reinforced with either steel, or composite reinforcement with glass or carbon fibres and subjected to experimentally simulated fire load. After cooling, bending test have been executed. Above mentioned experimental program was further complemented by extensive numerical analysis. Finally, presented work provides guidelines regarding further investigations required in this field of research.
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Speckle noise suppression
Kuchař, Otakar ; Hesko, Branislav (referee) ; Mézl, Martin (advisor)
Master thesis deals with the study of ultrasound. The first part of this work is devoted to basic physical principles, imaging modes, ultrasound probes, biological effects and the last part is associated with the artifact associated with ultrasound waves. In the next part the specific noise called speckle noise is detaily discussed. The description includes both a mathematical and a statistical view. Several methods are described to eliminate this noise. In the practical part the described methods are realized and compared based on objective and subjective evaluation.
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Power measurement in ultrasound fields
Škůrek, Pavel ; Čížek, Martin (referee) ; Rozman, Jiří (advisor)
This work is focused on the developement of a sensor, which enables to measure the ultrasonic power by heat effect of the mechanical Wales. The princip of two basic kinds of thermoacoustic sensor is descibed here – one level and two level sensor. This work also contains a proposition of these sensors with description of each parts and a trial to find suitable absorber. Achieved results, which support the function of the sensors are presented here by form of graphs and tables. Measuring by thermoacoustic sensors is confronted here with measuring of ultrasonic by hydrophone, which is used as reference measuring.
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Simulation of ultrasound sequences in contrast mode
Staňková, Jana ; Mézl, Martin (referee) ; Harabiš, Vratislav (advisor)
This bachelor thesis deals with the principle of contrast imaging techniques for ultrasound imaging. In the first part there are described basic principles and characteristics of ultrasound waves for the understanding. It is also focused on ultrasound contrast agents used in contrast enhanced ultrasound imaging. The important part is the description of perfusion models with a focus on obtaining perfusion parametres and analyzing perfusion curves obtained by measuring the ultrasound contrast agent over time. The second part is devoted to designing a program for generating simulated ultrasound images and description of the simulation of 2D ultrasound tomograms.
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Evolution algorithms for ultrasound perfusion analysis
Kolářová, Jana ; Odstrčilík, Jan (referee) ; Mézl, Martin (advisor)
This master´s thesis is focused on the application of evolutionary algorithms for interleaving data obtained by ultrasound scanning of tissue. The interleaved curve serves to estimate perfusion parameters, thus allowing to detect possible pathophysiology in the scanned area. The theoretical introduction is devoted to perfusion and its parameters, contrast agents for ultrasonic application, ultrasonic modality scanning, optimization, evolutionary algorithms in general and two selected evolutionary algorithms - genetic algorithm and bee algorithm. These algorithms were tested on noisy data obtained from clinical images of mice with tumor. The final part summarizes the results of the practical part and provides suggestions and recommendations for further possible development.
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Fast Reconstruction of Photoacoustic Images
Kukliš, Filip ; Dvořák, Václav (referee) ; Jaroš, Jiří (advisor)
The ability of reconstruction of photoacoustic images is important requirement to study soft tissues or vascular and lymphatic systems in high resulution but in small space. Today solution needs extensive computing power and it is noticeably time-consuming. In this study we would like to introduce a new solution which would be a way much faster and easy to use. My solution is up to 20x faster and needs forty percent less memory. This solution may be a better alternative for scietnist who study soft tissues by photoacoustic imaging.
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Design of Portable Ultrasound Device
Sedláková, Jana ; Buganská, Tamara (referee) ; Křenek, Ladislav (advisor)
The goal of bachelor thesis is proposing design of portable ultrasound device, which could be a complement of existing range of this type with respecting all technical and aesthetic requirements. This device should be convenient mainly for doctor’s necessities and for giving brief information about foetus of pregnant women
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Unconventional machining processes
Exnerová, Jitka ; Mouralová, Kateřina (referee) ; Kalivoda, Milan (advisor)
This thesis deals with the methods of the unconventional machining. The first part outlines the history of the machining methods, their characteristic and use follows. The second part aims at the method of the water jet, its technology, safety use, its advantages and disadvantages. Subsequently the thesis presents selected companies dealing with water jet cutting technology. At the end the thesis presents the environmental impact of the water jet cutting.
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