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Monitoring of buildings in relation to surrounding construction activity
Ledvoňová, Monika ; Heřmánková, Věra (referee) ; Cikrle, Petr (advisor)
This thesis deals with the monitoring of buildings disorders caused by surrounding con-struction activity. The first section describes the methods of monitoring failures, from the detailed inspection to the result evaluation, there is also given an overview of measuring instruments. The second part describes the methodology of passports implementation and contains an example of the object repassport that was violated by tunneling. There is a comparison of passport and repassport. The third largest section describes a practical ex-ample of monitoring object cracks around which the building activity took place. There is a documentation of failures, a description of the measuring spots choise, installation of the bases, monitoring, processing of results and conclusion.
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Characteristics features of luminescence radiation solar cells
Malý, Martin ; Šimonová, Lucie (referee) ; Stojan, Radek (advisor)
This thesis deals with characteristic features of luminiscence radiation solar cells during electroluminiscence. Electroluminescence is the process in which a substance begins to radiate electromagnetic radiation (luminiscence radiation) due to passing electrical current. Various defects in the structure of the photovoltaic cell can cause polarization of that radiation. The aim of this thesis is to measure some polycrystalline solar cells by electroluminescence. Selected solar cell is measured by electroluminescence extended by polarizing filter and afterward collected data are processed in MATLAB.
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Diagnosis of Pneumatic Cylinders Using Acoustic Emission Methods
Mahmoud, Houssam ; Baran,, Ireneusz (referee) ; Santos, Serge Dos (referee) ; Mazal, Pavel (advisor)
Tato práce se zabývá vývojem nového efektivního diagnostického postupu pro kontrolu funkce pneumatických válců pomocí metody akustické emise. Cílem práce bylo navrhnout a určit diagnostická kritéria pro hodnocení kvality vybraných typů pneumatických válců. Prvním krokem bylo nalezení typického akustického emisního signálu, který je spojen s určitým typem poškození ve válci využitím frekvenčního spektra signálu. Později byl tento parametr nahrazen parametrem RMS během sledování změn v průběhu testů. Na konkrétních válcích byl sledován vztah mezi akustickou emisí a různými typy defektů a byl představen nový přístup k určování těchto typů vad a jejich odlišením v signálu akustické emise. Druhý krok studie že neporušené a poškozené válce byly porovnávány tak, aby se zjistily výrazné rozdíly, které určují, zda je válec poškozen nebo nepoškozen. Několik nepoškozených válců bylo testováno akustickou emisí a následně v nich byly vytvořeny umělé vady. Signály z vysouvání a zasouvání pístu byly zaznamenány a analyzovány pomocí řady parametrů. Na základě časového zpoždění a normalizace RMS byly rozpoznány odezvy mezi poškozenými a nepoškozenými pneumatickými válci. Rozdíly byly zjištěny porovnáním maximální hodnoty RMS ze snímače upevněného na předním víku válce a snímače upevněného na zadním víku válce pro jeden cyklus. Poškozené a nepoškozené válce byly rozlišeny pomocí rozdílů energetických hodnot přítomných v signálech z obou snímačů v závislosti na zdvihu pístu. Konečné vyhodnocení válce bylo určeno výpočtem celkové hodnoty RMS. Ve třetím kroku experimentu byly válce postupně zatěžovány různými závažími ve svislém směru. Signály akustické emise byly zaznamenány z vysouvání a zasouvání pístu a poté analyzovány. Časové zpoždění se vypočítává z digitálního vstupu a začátku pohybu pístu. Energie signálu a RMS akustické emise porovnávají různé reakce v poškozených a nepoškozených pneumatických válcích s a bez zatížení. Výsledky testu ukázaly lineární vztah mezi křivkou RMS a zatížením. Defekty ovlivňují vztah mezi aplikovaným zatížením a zaznamenaným signálem snímačů.
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Identification and detection of defects on the PV system - operational measurement
Leitman, Valentín ; Morávek, Jan (referee) ; Mastný, Petr (advisor)
This work deals with the problem of identifying and detecting faults in photovoltaic systems. This thesis includes theoretical knowledge related to photovoltaic panels, the definition of measured parameters of the PV system and five ways how to identify faults in PV systems. The last part of this bachelor thesis deals with the author's contribution, which is to introduce a system for continuous monitoring data. System for continuous monitoring of data consists of measuring the power output of a photovoltaic panel and measurement using optical diagnostics using thermal camera. In conclusion are summarized individual knowledge, evaluation and recommendation of appropriate measurement methods for the detection of faults in PV systems.
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System for electroluminiscence defect detection of solar cells
Marčík, Silvestr ; Jandová, Kristýna (referee) ; Vaněk, Jiří (advisor)
The master thesis focuses primarily on issues of photovoltaic cells in terms of their defects. The introductory part deals with the history of photovoltaics, their introduction into practice and finally an explanation of the photoelectric effect itself. The thesis also describes photovoltaic cells themselves. It explains their principle, advantages, disadvantages and the creation of photovoltaic systems. A substantial part of the work is focused on the topic of detection of defects using luminescent methods. Subsequently, it describes procedural defects arising from the improper handling of already manufactured products. The final part deals with the main topic of the work, which is a detection using luminescence methods and it also mentions the non-luminescence method LBIC. The practical part of the master thesis contains the analysis of the current solution and of the subsequent proposal of solution using a low cost camera. It describes how to modify the camera, verify its spectral sensitivity using a spectrometer and measure the sensitivity of the CMOS sensor. The conclusion is focused on verifying the functionality of the proposed solution on different sources of infrared radiation and photovoltaic panels themselves.
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Prevention of defects during tube bending
Procházka, Libor ; Štroner, Marek (referee) ; Peterková, Eva (advisor)
The bachelor thesis describes the most occurring defects of tube´s component bending. The first part of this thesis is focused on a detailed research of these unwanted phenomenons. The second part contains complete list of possibilities in the defects reduction. There are quoted the suitability and the terms of use for an individual eliminative methods in the second part of this thesis, too. The last part of this bachelor thesis contains classifying of elimination possibilities to the particular types of defects.
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Airless Tires
Hanus, Jan ; Pacal, Bohumil (referee) ; Molliková, Eva (advisor)
The aim of this bachleor thesis was describing options of constructing the airless tire with inner structure, finding out its properties and comparision with conventional tire. The first part deals with the historical development of the airless tire structure. The second part describes ways to design the inner structure with focus on the honeycomb type. The comparison of airless and conventional tire properties is stated in the end of this bachleor thesis.
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Influence of Tyre Defect on the Driving Dynamics of a Vehicle
Kubík, Adam ; Bradáč, Albert (referee) ; Panáček, Vladimír (advisor)
In this thesis, an effect of a tyre defect on the driving dynamics of a vehicle is dealt with. The first part of the thesis is mainly concerned with the vehicle dynamics, road resistance, adhesion, orientation characteristics of the tyres and slowing down. This chapter is followed by an overview of the manufacturing process and construction of modern passenger car tyres. The practical part is focused on driving tests that are used to demonstrate the influence of tyre defects on handling characteristics of the vehicle. The main focus of this thesis is on directional variation, braking distance, deceleration and lateral acceleration. The very end of the thesis concentrates on tyre defect in higher speeds and its after-effects as well as precautions for mitigation of these after-effects.
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Reliability of LED Panels Solder Joints
Šimon, Vojtěch ; Špinka, Jiří (referee) ; Starý, Jiří (advisor)
Thesis is focused on the effect of heating factor on quality of solder joints. In theoretical part is solved reflow soldering technology, problematice of solder paste choice or criteria of soldering profile setting. The practical part is dedicated to demonstrating the impact of heating factor on solder joint quality. There are used X-Ray analysis, microsections and electron microscopy. In the final part of this thesis are summarized knowledge from theoretical part and experimental obtained results to defend of next steps in diploma thesis.
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