|
|
Magnetic fields for medical experiments
Punčochář, Marek ; Cipín, Radoslav (referee) ; Patočka, Miroslav (advisor)
his work deals with the creation of magnetic fields for medical experiments. The first part deals with different types of coils, with a focus on the Helmholtz coil. Longer be described here how the winding coil-shaped mats, calculate the length of the field lines. After the work is focused on the involvement of the coil into the circuit.
|
|
|
Use of Vibrodiagnostics in Forensic Engineering
Záleská, Veronika ; Bradáč, Albert (referee) ; Panáček, Vladimír (advisor)
This thesis deals with the measurement and evaluation of vibration on selected parts of car. Part of the work is devoted to the theory of vibration and noise, which includes, among others, presentations of common disorders of machine parts in terms of vibration. In the practical part of the work were performed out measurements described here and the results analyzed. Last part is in short devoted to the possibilities of using a similar measurement in forensic engineering.
|
|
| |
|
|
Powertrain Vibration Solution using Computational Modelling
Zubík, Martin ; Prokop, Aleš (referee) ; Novotný, Pavel (advisor)
The thesis solves vibration of simple combustion engine model as a basic step for evaluating the noise of engine. On the basis of computational model realized in software MBS ADAMS, which contains all significant input parameters, there are found normal velocities of the one cylinder four stroke engine block surfaces. The outputs are then processed into the integral characteristics that define the level of possible emissions for whole acoustic spectre. Two variants of the engine block were solved and in the end the summary of solution approach was made.
|
|
|
Oscillatory Power Generator Base on Mechanical Resonant Element
Mihalík, Vlastimil ; Houška, Pavel (referee) ; Hadaš, Zdeněk (advisor)
This work deals with the power supply of wireless sensors. When using a wireless sensor is desirable application of alternative energy sources, because the primary cells or batteries may reduce the extent or length of service of the sensor itself. Ambient energy can be used as a suitable alternative source. This energy must be in an appropriate form, which allows its conversion to electric energy. These appropriate, already used types include: solar en., temperature gradient en., en. of flowing liquids, vibration, etc. The advantage of vibrations is its presence in almost all mechanical systems. One of the possibilities for using the vibration of machine systems for power supply wireless sensors is using the vibration power generator with oscillating component. The generator must be designed so that its resonance frequency coincides with the frequency of vibration in the machine system. This method can be used only if the machinery system vibrations at least partially constant. Another option is to use the vibrations caused by, for example, transit transport, or different step acting factor. In this case, it is desirable that the generator is designed with variable resonant frequency, which can partly be achieved, for example, integrating several oscillating component in the body of generator. After the general analysis of the problem, graduation theses will be concerned with the possibility of use of energy from the short damped oscillation and step impulse. Focusing on a proposal of multi-element structures.
|
|
|
Blood pressure meter
Průdek, Ctirad ; Sekora, Jiří (referee) ; Čech, Petr (advisor)
In my master's tehsis I'm dealin with the methods used for non-invasive blood pressure measurement. For realization of a virtual blood pressure meter in LabVEW I have chosen the oscillometric method. Algorithm determining systolic and diastolic blood pressure is based on the relatively easy detection of maximum amplitude oscillations (corresponds with a mean arterial pressure), when thelimiting valuesof blood pressure are in a specific ratio with a maximum amplitude of oscillation. In LabVIEW was solved loading of signal from the measure card and processing pressure curve into a form suitable for the detection of the peak oscillations. The program calculates the limits of arterial pressure and mean heart rate too. Linking the virtual device with the blood pressure sensor Vernier BPS-BTA then makes up komplex for capturing the blood pressure via oscillatory method.
|
|
|
Principles and types of hydrodynamic valves
Havelka, Milan ; Himr, Daniel (referee) ; Pochylý, František (advisor)
This thesis deals with characteristics of the most commonly used valves in hydraulic systems. The aim was to create an overview of available features and define their brief characteristics. The emphasis was placed on their function and principles of task performance in a hydraulic circuit. The second part of the thesis is aimed at solving the issue of valves oscillation and subsequent optimization of constants that function as factor dampping.
|
|
| |
|
|
Interesting properties of microbubbles
Tesař, Václav
Paper investigates properties of very small, sub-millimetre sized gas bubbles in liquids,which are generated by oscillation produced by a fluiidic no-moving-part oscillato in the gas supply into the aerator. Of particular interest is the tendency of microbubbles to coalesce already while in immediate neighbourhood of the aerator exit. Another investigated property is oscillation driven by released surface energy. Autorr derived an equation describing the natural frequencty of the oscillation and with the help of this equation found interesting parameters of the processes, such as the amount of outside water that takes part in the oscillation and has a decisive role in the inertial properties of the variations of the microbubble shape.
|
|
|
Oscillation of a Bubble in Surfactant Solution
Vobecká, Lucie ; Vejražka, Jiří ; Zedníková, Mária ; Orvalho, Sandra ; Tihon, Jaroslav
The decay of shape oscillations of a bubble in solutions of a soluble non-ionic surfactant are studied by means of high-speed imaging. The oscillations are induced by a sudden motion of a capillary, to which the bubble is attached. The bubble then either detaches or remains attached at the capillary. In both cases, the observed bubble shape is decomposed into eigenmodes (Legendre polynomials). The frequency f and the decay time τ of the lowest oscillation mode are evaluated. Their dependences on the surfactant concentration c, on the bubble size and on the bubble age are studied.
|
guest ::
