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The beginning kindergarten teacher
HOŘEJŠÍ, Jana
The bachelor's thesis focuses on beginning teachers and their induction into practice. It summarizes the requirements for kindergarten teachers, focuses on their induction and focuses on forms of self-reflection or psycho-hygiene. The aim of the thesis is to find out what the means of induction are and whether the perceptions of employment of kindergarten teachers differ from reality. The theoretical part discusses the required education, the requisites of the job. Attention is also paid to beginning teachers, their induction and the possible pitfalls that accompany the beginning. Self-reflection of teachers is also addressed, as well as psycho-hygiene, to prevent burnout syndrome. A semi-structured interview ascertains the actual beginnings of beginning teachers, as well as their expectations and subsequent awareness of reality.
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Electronic RLC meter
Dvořák, Radim ; Hanák, Pavel (referee) ; Lattenberg, Ivo (advisor)
This work deals with measurement methods of passive components R, L ,C used almost in every electrical circuit. Work describes progress of choosing the right methods for measurement and also the process of designing the autonomous RLC meter with use of ATMEL microprocessor chips. The RLC meter will be powered from rechargable battery and will be able to measure primary attributes of RLC components.
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Efficiency Improvement of Small Induction Motors
Vilím, Martin ; Veselka, František (referee) ; Hájek, Vítězslav (advisor)
In this bachelor´s thesis I discuss about asynchronous engines in general, describe their construction and principle of operation, using. It also includes measurements of a specific motor and design engine. The first part deals with theprinciple of the engine options including the fundamental control over speed and torque. The second part deals with the measurement of the size of the searchengine and losses. The last part provides a proposal for a new induction motor.
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FEM model and simulation of induction motor with pole-changing winding
Záškodný, Jiří ; Ondrůšek, Čestmír (referee) ; Vítek, Ondřej (advisor)
This master thesis deals with calculations and simulations of multi-speed induction motors. In the first part, basic principle of these machines is described. Next, there are given three examples of pole-changing stator windings and their properties are analyzed (winding factors, magnetomotive force). Main part includes simulations and measuring of the specific motor, which is produced by company Siemens Mohelnice. This is the motor with 2/1 pole-changing in Y/YY connection. First, influence of skewed rotor slots on current and torque is analyzed. Next, parametres of motor from simulations are given and these results are compared to measured values.
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DC/DC step-up converter for notebook
Škunda, Michal ; Klíma, Bohumil (referee) ; Červinka, Dalibor (advisor)
Given bachelor’s thesis devoted to a proposal and implementation of transducer STEP-UP for supplying of notebook in car. Introduction presents dividing of switching power supplies followed by a choice and a proposal of power supply. In this work we can find the specific proposal of inductor, the proposal of electronic connexion and the proposal of PCB layout. There is a software EAGLE used for the design of PCB layout. In the last part of work there are particular courses of current and voltage that characterize power supply pictured. The work contains measured load characteristic of switching power supply loaded by notebook as well. Notebooks need to have quality power supplies that is why there was a special attention paid to the quality of supply and its electric parameters.
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The simulation of steel rod improvement by the induction lines heat treatment
Chmiel, David ; Turoň, Rostislav (referee) ; Kouřil, Miloslav (advisor)
Bachelor thesis deals with possibilities of simulation of induction heat treatment. Literary analysis is focused on the method of induction treatment, the physical nature and its use for the heat treatment. For completeness is in the end comparison of different methods of heat treatment. The experimental part describes the future of quenching and tempering of steel bars in company Třinecké železárny a.s. Also is contained method of simulation of the heat treatment in computer program QTSteel and the subsequent design of parameters for a continuous processing.
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Wireless charging station
Pokorný, Josef ; Hrabina,, Jan (referee) ; Janoušek, Jiří (advisor)
The paper deals with possibilities of wireless charging and transmission of electric energy using inductive coils. Basic models of air coils are described using CST simulation software. The product consists of a transducer for transmitting coil, two coils with ferromagnetic shield, synchronous rectifier and battery charging circuit. Communication is provided by an 8-bit microcontroller with wireless modules and an ethernet shield for online monitoring. The aim of the thesis is to design a wireless charging station with a power transfer of 40 W with the possibility of online monitoring of the charging state.
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Modeling of torque-speed characteristics of induction motor
Michalík, Marek ; Chrobák, Petr (referee) ; Vítek, Ondřej (advisor)
This master thesis deals in first part with basic theory of an induction motor and principle of function. It also includes theory about higher harmonics of magnetic field and how asynchronous and synchronous torques are created. Various ways how to decrease effect of these torques are suggested. These findings are later applied in practical analytical calculation in second part, in which all parameters of motor are calculated from given dimensions of motor from technical documentation. This is done for basic and higher harmonics. After that a model of this motor was created in RMxprt program, which also calculated all parameters of this motor and created torque characteristic. This motor was also modelled in ANSYS Maxwell 2D. Additional simulations for finding out influence of harmonics on torque characteristic were also done in this software. Torque characteristic of motor was also practically measured in laboratory. All results were compared and evaluated.
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Forming lines molding hot weighing up to 100 kg
Smyček, Ondřej ; Humlíček, Jaroslav (referee) ; Omes, Jiří (advisor)
This project was made within the engineering studies and its aim was to design an assembly line to product assigned components of appropriate quality and quantity, using the technology of hot extrusion, both backward and forward. A series of technology steps was suggested, parameters necessary for individual operations were set and on this basis, adequate machines were chosen. The conclusion of this work contains technical-economical evaluation for the chosen options which expects the ten-year return with average production of 40 000 pieces.
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Calculation of parameters of small induction motor
Vojče, Zbyněk ; Cipín, Radoslav (referee) ; Vítek, Ondřej (advisor)
This bachelor thesis deals in the first part with a construction and a principle of function of an induction motor. In the second part deals with an actual analytical calculation of three-phase low power induction motor. Is performed a simulation in a program Ansoft RMxprt, which calculated the characreristics of the motor analytically and simulation in program Maxwell 2D by finite element method. The aim of the work is to compare results of simulations with results of analytical calculation.
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