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Wireless security facility
Gargulák, Lukáš ; Morský, Ondřej (referee) ; Zeman, Václav (advisor)
The content of this thesis is the design, construction and programming of wireless security device. This wireless security system consists of two units. Personal unit and sensor unit. This thesis compares two ISM bands 433 MHz and 868 MHz. The thesis presents a selection of parts for construction wireless security device. The work also deals with the structure of transmitted frames on the link layer. Marginally are discussed ways to reduce consuption AtmelAVR microcontrollers and also two ways of charging Li-Ion battery. It also outlined the firmware of both units. Its complete source code is included on the DVD.
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Comparison of parameters of selected types of commercial lithium-ion batteries
Špina, Martin ; Libich, Jiří (referee) ; Bača, Petr (advisor)
This thesis deals with operation principles of Lithium-ion battery. It evaluates its characteristics, advantages, and disadvantages. Technological processes and materials used in manufacturing and recycling are also discussed. Practical part of the thesis evaluates initial capacity of given Li-ion cells at different loads. Batteries are then cyclically charged and discharged, and its capacity and other parameters are determined. Electrochemical impedance spectroscopy data are also taken and evaluated for batteries in new-like condition, used batteries and cycled batteries as the capacity fades.
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Wireless Sensory Network Using LoRa Technology
Mikulášek, Michal ; Pokorný, Jiří (referee) ; Škorpil, Vladislav (advisor)
The bachelor thesis focuses in the first half on the Internet of Things and the available wireless technologies for the Internet of Things. Each technology is characterized by its features, pros and cons, as well as the possibilities of using it in the Internet of Things. In the second half of the thesis, a practical design and construction of a LoRa network, consisting of a sensory and a central unit, is carried out. The parts of the solution are designed wiring schemes, printed circuit boards and detailed photo documentation. Additionaly the software solutions for both types of units are described, with detailed descriptions of the proposed features. The maximum possible range is tested and documented for the entire solution. Subsequently, a detailed measurement of the power consumption of the sensor unit is carried out and an extensive estimation of its battery life for a selected battery.
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Controll Electronics for Effective Supplying of Equipment with Li-Ion Accu by Solar Cells
Horký, Luděk ; Dřínovský, Jiří (referee) ; Urbanec, Tomáš (advisor)
This Bachelor`s thesis deals with questions surrounding the collection and harnessing of solar radiation for use as electrical energy. The aim of this project was to build an effective system for charging Li-Ion batteries by means of solar cells. To this end, four different solar panels currently available were chosen for measuring and evaluation. The most suitable of these was chosen and an electronic control system devised for effectively supplying the Li-Ion batteries. It was necessarily to make solution for problems consequent upont this method of charging this type of battery and make practise realizitaion of this electrical scheme by SMT technology.
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Materials and Components for Lithium-Ion Power Sources
Jirák, Tibor ; Kadlec, Jaromír (referee) ; Paidar,, Martin (referee) ; Vondrák, Jiří (advisor)
The dissertation thesis deals with electrode materials and components for lithium-ion power sources. The thesis works with two different kinds of materials, concretely nanostructured Li4Ti5O12 with spinel basis and LiCoO2 with layered structure. The electrochemical properties, structure and element analysis and utilization possibilities in electrochemical industry of new technological electrode material Li4Ti5O12 were investigated. The influences of admixtures and electrolytes on characteristics of electrode materials with aforesaid active masses were also examined. Low cost price, environmental safety and obtained results of electrochemical measurements and structure analysis refer to wide possibilities of usage electrode material Li4Ti5O12 in the field of electrochemistry.
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USB battery tester
Andrysík, Lukáš ; Langhammer, Lukáš (referee) ; Lattenberg, Ivo (advisor)
This bachelor's thesis contains construction of battery tester along with primary and secondary cells comparsion. It consists of four parts - the first one focuses on general description of the most commonly used electrochemical cells, their characteristics, advantages and disadvantages. Second one relates to design a custom equipment for testing these cells including software, parts values calculations and common problems with the design. Third part is mainly about mechanical design and PCB manufacture. The last section is devoted to comparsion of several models of cells in terms of capacity and performance under different conditions.
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Capacity meter for Li-Ion and NiMH accumulators
Pinďák, Lukáš ; Cipín, Radoslav (referee) ; Huták, Petr (advisor)
The goal of this bachelor thesis is primarily theoretical analysis of battery problems, analysis tester capacity of Li-ion and NiMH accumulators and its subsequent construction. The work consists of three main. The first part deals with the electrochemical current sources and their division, a brief description of their charging and final comparison commonly most used batteries. The second part of the thesis is already focused on the practical design of the capacity meter. In this section is explained the issue of measuring voltage, current and temperature of the battery and determination of their capacity. The last part describes the device software. The proposed devices allow measurement capacity Li-ion and NiMH cells at three different load modes and can be recharged after discharge.
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RF power meter
Hlaváč, Štěpán ; Jedlička,, Petr (referee) ; Drexler, Petr (advisor)
This master’s thesis describes various principles of measurement of electromagnetic waves in a free space and on a line. Used sensors and their real parameters are given for every method. The analysis of protections of high-frequency inputs of measuring instruments is done here and the most suitable method and protections of input for realization are chosen. The analysis of design of secondary protection of high-frequency input is done in this project. The protection of input is realized and measured. The suitable method of measurement is chosen as well as the sensor for measurement of power. The block diagram and circuit diagram of the meter of power are designed. According to designed conception the measuring instrument for measurement of power is realized and its single qualities are measured during the realization. In the final part its precision is measured and the evaluation of results is done.
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