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Piezoelectric nanofiber materials for wearable electronics
Frolíková, Štěpánka ; Škarvada, Pavel (referee) ; Macků, Robert (advisor)
This thesis deals with the influence of production parameters on the morphology of PVDF nanofibers produced by electrospinning. Nanofibers are generally a widely used material, nanofibers are generally a widely used material, they can also have piezoelectric properties, which gives them a specific spectrum of use, eg in biosensors. The production of nanofibers was realized by electrospinning. A scanning electron microscope was used to examine the morphology and surface properties. The aim of this thesis is to compare the properties of PVDF nanofibers produced under different settings of production parameters.
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Phase shifted harmonic oscillators for practical education
Hudec, Marek ; Petržela, Jiří (referee) ; Šotner, Roman (advisor)
This thesis focuses on designing a laboratory preparation for the study of phase-shift oscillators. The first part of the thesis comprises a theoretical discussion regarding the given problem. The laboratory preparation will include two types of oscillator circuits. An operational amplifier will be used as the amplifying element together with an RC feedback loop in one type of circuit whilst the other type will consist of operational transconductance amplifier employed as inverting amplifiers and generating feedback. The second part of the thesis includes the actual design of the preparation. The design process covers construction stage of the preparation, calculation of the component parameters necessary for oscillation to occur, simulations of the individual circuits along with THD analysis as well as with analysis of manufacturing variances. The second part of the thesis also contains the design of a separate block of all-pass filter. The simulation results will be verified experimentally, on a printed circuit board. In the last part of the thesis, I will evaluate and intercompare the theoretical, simulation and practical results.
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Modern low-emission combustion chamber for jet engines
Mašek, Jakub ; Nastálek, Ondřej (referee) ; Šplíchal, Miroslav (advisor)
Bachelor´s thesis examines modern low-emission combustion chambers for jet engines. It´s foremost aim is to specify construction parameters of low-emission combustion chambers, compare it´s features and comprise the use of these combustors in civil aviation. Thesis deals with reasons of modern low-emission combustion chamber development and estimate future development in the region of aircraft industry. Another aim is to specify legislations of aviation emissions, history of certification standards and organizations, which make and control these limits.
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Digitally controlled filter
Rez, Jan ; Szabó, Zoltán (referee) ; Friedl, Martin (advisor)
This bachelor's thesis deals with design of a functional prototype universal digitally controlled analog frequency filter 2th order. Part of the design is the selection of appropriate filter topology diagram and selection of an integrated circuit. Universal filter will contain lowpass, highpass, bandpass and notch filter. The filter is tuned in cutoff frequency from 100 Hz to 15 kHz. The bachelor's thesis focuses on the circuit analysis of selected concrete structure of universal filter and possibilities of digital control filters. The practical part of this thesis includes PCB design, control software for filter and graphical representation of measured results.
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Optimalization of Induction Furnace Operation in foundry Vsetín
Trachta, Jiří ; Nowak, Stanislav (referee) ; Lázničková, Ilona (advisor)
The aim of this work is optimalisation of induction furnace in foundry for company PROMET FOUNDRY a.s. The company has two induction furnances. There are installed as identical construction. They have 2 modes of operation. First mode is founding and second mode is mode, where is temperature in maintain mode. Only one induction furnance can work in the founding mode at a time though. Inducion furnances are in the single-phase connection and they cause unbalance in the distribution network. Near the foundry there is a small network area whitch it is operated by company Zásobování teplem Vsetín a.s. The consumption of electrical energy in foundry so big, that in the year 2009 was made elaborate for Zásobování teplem Vsetín a.s. It was write at Laboratoře diagnostiky výkonů (Laboratory of performance diagnostics), which is a part of Electrotechnic Department at Technical Univarsity of Ostrava. The ordered study was named “Verification of causes of increased reactive energy consumption during transition from electricity delivery to electricity consumption”. The conclusion of this assignment confirms that in distribution network in the Jiráskova area in Vsetín there is unbalance of electrical energy and there is high part of reactive power. The next conclusion is crucial to find the customer who made the unbalance and to set relevant remedy. The last step will be the identification whether such device can actually be effectively balanced. It was subsequently proved that the Promet Foundry was causing the unbalance and that balanced consumption would be reasonable. Promet Foundry thus addressed Autel a.s. company with an inquiry to make a study of removing the causes of the unbalance which is caused by current induction furnaces operation at a minimum possible cost, least possible influence on the performance and minimum construction changes concerning the building. In this thesis there will be some topics. The result of which will be introducing of used heating technology, introducing of company and of effective plant performance and subsequent suggestions of possible unbalance removal or reactive power decrease. Several ways which are being implemented in the industry in order to balance consumption will be described. A suitable balancing plant will be subsequently chosen and its parameters will be calculated.
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New solutions of converters for measurement of current-mode filters
Štork, Petr ; Kubánek, David (referee) ; Jeřábek, Jan (advisor)
This bachelor’s thesis describes some new solutions of differential converters that convert voltage to current and vice versa. Such converters are necessary for measurement of frequency filters in a current mode due to absence of instruments able to mesure signals with current as signal carrier. The goal is to design such converters that should influence gauged frequency properties in a current mode as little as possible. Converters will consist of operative amplifiers with current feedback. Converters designed this way are tested using simulations from PSpice programme, where particularly wideness of band of individual solutions is tested. Simulated solutions that are the most suitable ones are practicably re-enacted and gauged. These resuls of measurement and simulations are compared.
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Laboratory equipment aimed on the all-pass filters
Lokaj, Jakub ; Šotner, Roman (referee) ; Petržela, Jiří (advisor)
Theme of bachelor thesis is design and realisation of allpass filters. It consists of using pasive and active components in design of allpass filters and followed by realisation in laboratory equipment. Functionality was verified in simulating software LTspice and SNAP3v2. In real implementation were used integrated circuits such as TL071, AD844 and LT1228 for CCII+, OTA and design with op-amp. This bachelor thesis includes concept of laboratory equipment, where will be compared functionality of allpass filters with simulated results
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Preparation for the implementation of a prestressed bridge in the village of Hnojník
Stupka, Matouš ; Diaz, Yvetta (referee) ; Vlčková, Jitka Laura (advisor)
The subject of this diploma thesis is the preparation for the implementation of a prestressed bridge in the village of Hnojník. This thesis contains a technical report, coordination situation of the construction with broader relations to transport routes, phases time shedule, a feasibility study of the main technological phases, project of construction site equipment, a suggested list of the main construction vehicles and building mechanisation, time shedule of main construction, shedule of transport of fresh concrete mixture, technological regulation of concreting bridge deck, technological regulation of additional prestressing bridge deck, control and test plan, health and safety at work on bridge construction, The annexes contain drawings of concept of load-bearing falsework, drawing of the construction site equipment, drawing of coordination situation of the construction with broader relations to transport routes , itemized budget, graph of workers and machines needs, phases time shedule and delivery shedule of fresh concrete mixture.
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Architectural study of accessible / protected/ spaces
Kalíšková, Eliška ; Myslín, Jiří (referee) ; Boleslavská, Yvona (advisor)
This architectural study offers a solution of the Gemini High School‘s new bulding, /Brno Lesná, the bulding site number 202/9, Vaculíkova street/, and shows a new building of a house of culture with a commercial area instead of today’s school /the bulding site number 253/. The new way of car parking and strenghtened areas of this street are included. The building and pulling down of today’s houses and buildings are devided into 2 phases. In the first phase a new barrier – free school building with a possibility of accommodation and flats is designed /building site number 202/9. This bulding has got two entrances. One from the northern part is for a school and the second one in the west is for the tenants. The school area is spread among the first and the third floor (classrooms, canteen, offfices). The fourh floor is used for students‘ accommodation and for a terrace entrance. There are some flats (2+1, 3+ small kitchen, max. area 120 m) from the fifth to the tenth floors. In the underground the are some tenants‘ cellars and technological rooms for school. The renewed car parking for all the tenants, school visitors and others is provided in Vaculíkova street. After the firt phase of building the new school project will go into the second part. In that time the old school will be pulled down and a new house of culture is designed in this place. There will be restaurant, commercial area, cinema, library – café and gym – fitness. On the first floor there are a restaurant, a library – café a cinema. On the second floor there are a gym – fitness and a commercial area. Car parking for the visitors is provided in the underground - 52 cars + 4 handicapped people. The green roof of this house is designed to be comfortable to watch it from the neighbourhood and do not damage the look of this new building. To finish all this project means to create the public area between the two new buildings. A nice place for meeting people and a cultural events will be bo
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Phase shifted harmonic oscillators for practical education
Hudec, Marek ; Petržela, Jiří (referee) ; Šotner, Roman (advisor)
This thesis focuses on designing a laboratory preparation for the study of phase-shift oscillators. The first part of the thesis comprises a theoretical discussion regarding the given problem. The laboratory preparation will include two types of oscillator circuits. An operational amplifier will be used as the amplifying element together with an RC feedback loop in one type of circuit whilst the other type will consist of operational transconductance amplifier employed as inverting amplifiers and generating feedback. The second part of the thesis includes the actual design of the preparation. The design process covers construction stage of the preparation, calculation of the component parameters necessary for oscillation to occur, simulations of the individual circuits along with THD analysis as well as with analysis of manufacturing variances. The second part of the thesis also contains the design of a separate block of all-pass filter. The simulation results will be verified experimentally, on a printed circuit board. In the last part of the thesis, I will evaluate and intercompare the theoretical, simulation and practical results.
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