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Optoelectronic application of perovskite nanoparticles
Ambro, Filip ; Zdražil,, Lukáš (referee) ; Pospíšil, Jan (advisor)
This bachelor thesis deals with the utilization of perovskite nanoparticles in optoelectronics. The thesis is composed of three main parts. The first part focuses on the theoretical properties of perovskite materials, with an emphasis on their structure and properties influencing their electrical and optical behavior. The second part describes the procedure for preparing solutions of these nanoparticles, their subsequent characterization, the preparation of thin layers, and the subsequent characterization of the optical, electrical, and dielectric properties of these layers. The final part is dedicated to presenting the results of the work and discussion.
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Proposal for the Extension of the Functionality of Electronic Shelf Labels for the Improvement of Communication with Customers
Petýrková, Pavlína ; Pospíšil, Jan (referee) ; Chlebovský, Vít (advisor)
The topic of this thesis is a proposal to expand the functionalities of electronic shelf labels to enhance communication with customers. The thesis is divided into three parts – theoretical, analytical, and proposal. The theoretical part is based on professional literature and is crucial to a deeper understanding of the issue. It also serves as a basis for the analytical part. In its introduction the company DATART is presented. The analytical part then deals with answering partial research questions interviews, questionnaire survey and observation. Based on the results of the analysis, the proposal part develops proposals focusing on specific measures and strategies that will meet the defined objectives.
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Using of Perovskite Nanoparticles in Biochemistry
Srncová, Melanie ; Tumová, Šárka (referee) ; Pospíšil, Jan (advisor)
This bachelor's thesis examines study of the properties of lead halide perovskite nanoparticles and their use in biochemistry. The synthesis of two types of perovskite nanoparticles MAPbBr3 and MAPbCl3 was performed using the LARP method. During the synthesis was observed the influence of the mixing length of the precursors on the properties of these solutions, which were characterized using UV-VIS spectrophotometry, fluorescence spectrometry and dynamic light scattering. A discussion of the obtained results was carried out along with a discussion of the suitability of using these perovskite nanoparticles in biochemistry due to the toxicity of the lead that these nanoparticles contain.
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Model of electric charge transport in perovskites and their precursors
Raška, Vilém ; Pospíšil, Jan (referee) ; Zmeškal, Oldřich (advisor)
Thesis focuses on analysis and determination of basic electric properties of perovskite materials. Thesis includes theoretical section which discusses electric properties and charge transport in solid materials. In the experimental section several chloride and boride perovskite material samples are used for measurement of VA characteristics and Impedance Spectroscopy. Then based on acquired data multiple models are created which are then used to determine required properties and state distribution of samples.
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Study of multilayer perovskite structures properties
Gabzdyl, Adam ; Kratochvíl, Matouš (referee) ; Pospíšil, Jan (advisor)
The bachelor thesis focuses on the optical, electrical and dielectric properties of perovskites and their multilayer structures for use in optoelectronic applications. Samples of lead MAPbI3 and lead-free Cs3Bi2I9 perovskite in a photovoltaic cell of FTO/SnO2/perovskite/spiro-OMeTAD/Au structure were prepared and studied. The optoelectrical properties were determined by direct current measurement of current-voltage characteristics and the dielectric properties were determined by impedance spectroscopy. It was determined that with this photovoltaic cell structure, lead perovskites are a more suitable material for optoelectronic applications than lead-free perovskites because they exhibit many times higher solar energy conversion efficiency and possess more favorable electron processes.
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Lighthouse for maritime communication
Chadima, Jan ; Mašek, Pavel (referee) ; Pospíšil, Jan (advisor)
This bachelor thesis deals with design and construction of lighthouse model, which will be used for teachning. It describes types of naval signalizacion, which are established by organization IALE in decree E-110. In thesis is described Arduino platform, metods of 3D printing and used materials For model needs was designed printed circuit board with microcontroller ATmega328P, which control RGB LED. Program, which control model, was writed on Arduino platform. Program has nine modes of sea light comunication. It can change periode, color of LED, brightness and turning on power saving mode. The result of this work is a functional model of lighthouse powerd by battery. Model is based on Green Cape Lighthouse in Australia in scale 1:58.
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Study of electric properties of thin films of perovskite precursors
Harna, Václav ; Pospíšil, Jan (referee) ; Zmeškal, Oldřich (advisor)
High efficiency perovskite solar cells may be the solution to obtain cheap renewable solar energy. However, characteristics of crystalline perovskite materials suitable for solar cells are not yet all clearly understood. In this thesis was studied and optimized the preparation of perovskite methylammonium lead tribromide (MAPbBr3) crystals using anti solvent vapor assisted crystallization (AVC). These crystals were prepared and studied in a small channel between two carbon electrodes on 3D printed substrate made from polylactic acid (PLA) connected to a larger electrode system were measuring took place. Electrical properties of prepared crystal structures were studied using current voltage characteristic and the process of crystallization was documented. Crystal prepared by AVC method achieved sizes larger than 0,5 mm, their electrical conductance increased with their size and the crystals were photo and thermal sensitive. During crystallization of MAPbBr3 precursors from solution was found that a certain structural change exhibiting an increase in electrical conductance takes place in the presence of MABr. The setup of PLA substrate and measuring electrode system creates great opportunities for study of other perovskite materials and may be able to uncover some of the mysteries that these fascinating materials hold.
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Honeypot for LoRaWAN protocol
Zhukova, Viktoriia ; Pospíšil, Jan (referee) ; Pospíšil, Ondřej (advisor)
The bachelor’s thesis in the theoretical section focuses on LoRaWAN technology. It describes network communication, LoRaWAN security, vulnerabilities, and mitigation measures. The second half of the theoretical section focuses on describing honeypot technology and its distribution, listing its advantages and disadvantages, and comparing IoT honeypots. The practical section focuses on building an experimental environment. There is a description of the selected hardware and software. It describes the commissioning of the LoRaWAN network, the configuration of the gateway, and the startup of the LoRaWAN server. Next, the whole procedure of honeypot assembly is described. Two variants of high-interaction honeypot are described and investigated. One without the use of sandboxing and using a firewall, the other with the use of sandboxing and an implementation of chroot/jail.
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Multi-Level Association Rules Module of a Data Mining System
Pospíšil, Jan ; Bartík, Vladimír (referee) ; Zendulka, Jaroslav (advisor)
This thesis focuses on the problematics of implementing a multilevel association rules mining module, for existing data mining project. There are two main algorithms explained, Apriori and MLT2L1. The thesis continues with the datamining module implementation, as well as the DMSL elements design. In the final chapters deal with an example dataminig task and its result comparison as well as the whole thesis achievement description.
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Analysis of Bicycle Race Grand Prix of Kuřim
Pospíšil, Jan ; Ing.Lubomír Stříž (referee) ; Drnek, Jiří (advisor)
The Bachelor thesis is aimed of organizing bike races Grand Prix of Kuřim. The first part is devoted to the theoretical background for creation of analysis and explanation of important concepts in mountain biking. The second part is focused on application of analysis. The last section contains suggestions for improvements and increase the attractiveness of the races.
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