National Repository of Grey Literature 339 records found  beginprevious31 - 40nextend  jump to record: Search took 0.00 seconds. 
Virtual instrument for experimental ultrasonic measurement
Dufek, Ladislav ; Harabiš, Vratislav (referee) ; Kolář, Radim (advisor)
This bachelor’s thesis is about usage the virtual instrument created in LabVIEW environment for measurement of ultrasonic transducers and for resulting signal scanning. It briefly describes the basics of ultra acoustic and the principles of piezoelectric transducers. Then problematic of generation and scanning signals using cards National Instruments NI-PCI 5401 and NI-PCI 5102 are explained. Subsequently an instrument is designed. This instrument is used for experimental measurement at 4 pcs engineering samples of ultrasound transducers, is painted the frequency response characteristic and determines frequency of resonance.
Cheap device for non-invasive detection of blood flow
Mívalt, Filip ; Majzner, Jiří (referee) ; Sedlák, Petr (advisor)
Blood flow measurement by Doppler effect is widely used technique for the assessment of blood vessels condition. Stenosis, aneurysm and blood insufficiency might be revealed by this method. In recent years, measurement devices based on Doppler effect haves been introduced also in veterinary medicine. For example, peripheral blood pressure of a cat might be observed at tail or paw. This thesis deals with the design of blood flow Doppler detector prototype and its implementation to fully operational instrument. Proposed device is uses a low-cost doppler probe. Blood flow detection is based on the analysis of Doppler probe output signal discrete power spectrum. The frequency spectrum is determined from digitized preprocessed analog signal. This thesis should illustrate the possibility of usage of Arduino platform and cheap ultrasound vascular probe as alternative for expensive Doppler devices.
Autonomous Landing System for Quadrocopter
Vomočil, Jan ; Kopečný, Lukáš (referee) ; Žalud, Luděk (advisor)
This thesis describes the design and implementation of systems for automatic landing and stabilization of air vehicle known as Quadrocopter. It focuses on image processing from a camera placed on board of the robot. The aim of image processing is detect landing target and calculate the distance from the desired position. Further is solved vertical stabilization for higher altitudes. For this function is measured atmospheric pressure. Conversely, for low altitude flight is used a ultrasonic range finder. In the conclusion is solved the implementation of the system.
The properties of ultrasonic equipment for directional messages transmission
Klíma, Martin ; Král, Michal (referee) ; Bajer, Arnošt (advisor)
In work are under examination properties of equipment for spatially selective propagation of acoustic signal with usage ultrasonic carrying frequency. Further is shown summary accessible informations about this problems. Part of work includes analysis of possibility low-cost realization of such equipment.
Detector of bubbles in blood
Foltýn, Vojtěch ; Sekora, Jiří (referee) ; Rozman, Jiří (advisor)
ABSTRAKT This thesis is the theoretical part deals with various ways of cleansing the blood, with a focus on hem dialysis. Describes the technical solution and monitor the dialysis flow diagram of blood and dialysate. The paper describes various solutions to detect bubbles in the blood and their advantages and disadvantages. Based on the best method of detection are designed detector bubbles. Working in the practical part contains a proposal detector set for venous diameter of 20 mm. Equipment to detect bubbles allows for connection to a blood pump discontinue its activities. Output works are drawing diagrams, printed circuit board design and implementation of graphs circuits.
Thermoacoustic measurement of ultrasonic power
Vysoudil, Ladislav ; Čížek, Martin (referee) ; Rozman, Jiří (advisor)
The assignment of this work is to suggest structural design of thermoacoustic sensor and experimentally verify his function for testing intensity of ultrasound diagnostic systems. Then the measured results are compared with measurement by the hydrophone in ultrasonic measuring tank. Opening part of this work is focused on functional description of sensors and their construction, including functional description and construction of hydrophone. The rest of the work deals with project of thermoacoustic sensor and measuring with sensor and hydrophone and evaluation results of measurement. Intention of this work is to verify the correct function of designed thermoacoustic sensor with the help of comparison measurement with hydrophone.
Doppler blood flow detector
Klügl, Jan ; Čech, Petr (referee) ; Rozman, Jiří (advisor)
This bachelor's thesis is engage in suggestion of nondirection doppler blood flow detector with unmodulated carrying wave. At first the thesis describes indicator's principle of working and mention the systemic proposal for working frequency and intensity of ultrasound. Later in detail describes individual blocks, which are the detector consist of. At every block of system is mentioned the diagram of connection and values of components, which are ascertained from calculation, simulation and recommendation of producer.
Model nonlinear effect in ultrasound fields
Kulík, Tomáš ; Čech, Petr (referee) ; Rozman, Jiří (advisor)
The main topic of this diploma thesis is the modeling of nonlinear effects in ultrasonic fields. The work deals with application of finite difference method (FDTD) on the Westervelt equation and the subsequent creation of the model of ultrasonic fields in MATLAB. This thesis also includes theoretical analysis of ultra-acoustic and technical aspects of diagnostic ultrasonography. In addition, this document includes verification of theoretical assumptions by using created model.
Properties measurement of ultrasound system in ophthalmology
Grebíková, Lucie ; Mézl, Martin (referee) ; Harabiš, Vratislav (advisor)
The thesis deals with physical principles of ultrasound with following specialization on ophtalmic ultrasound system Nidek Echoscan 4000 and its properties. And also it deals with description of investigative techniques in ophthalmology (A-mode, B-mode, biometry and pachymetry). Next, they was suggested procedures of measurement and that is spatial resolution (axial and lateral spatial resolution) and propagation speed of ultrasound depending on the temperature. Then these properties was tested on laboratory phantoms of eye – ETETECH LTD. and Multipurpose Ultrasound Phantom but on created phantoms of eye too, which will be made from agarose gel with build-in materail (fishing line, plastic film, plastic bag and rubber). At the end, measured values was processed in the generated program.
Specifics of assessment of old concrete structures
Mička, Michal ; Žítt, Petr (referee) ; Cikrle, Petr (advisor)
The bachelor thesis deals with evaluation of properties materials concrete structures of former textile factory Vlněna from the 19th century in Brno. The content of this work is divided into the theoretical and practical part. The theoretical part deals with the description of the methods used in the research of reinforced concrete structures, comparison of the types of beams used in the past with used today and unlike the principles of the design of reinforced concrete structures in the 1920s and 30s of the 20th century compared to the present time. There are also described components, properties and technologies of concrete production in the period between the war and the comparison with the present time. The practical part consists of on-site examinations and sampling. A large part consists of the evaluation of laboratory tests on the test samples taken from the solved part. A total of 24 test samples were performed. It also compares the strength of the concrete reinforcement with the reinforcement used today.

National Repository of Grey Literature : 339 records found   beginprevious31 - 40nextend  jump to record:
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