110 research outputs found
Processor PIC18F46K22 applied as DTMF generator
Submitted article describes an application of microcontroller PIC18F46K22 for generating DTMF (Dual Tone Multi-Frequency) signal. Used microcontroller is optimal for this application - it has timers with compare facilities, sufficient number of PWMs, powerful instruction set (extended - in comparison to classic PIC16xxx microcontrollers), etc. problematic of article relates to more branches - electronics, filters, signal generators, microcontrollers, telecommunications, programming. An important purpose was to create an experimental platform based on powerful microcontroller enabling implementation additional functions. There are together three different solutions of DTMF generating are described in article, they are compared as to the demands on external hardware and machine time of microcontroller. The first solution is based on sinus table, truncated onto 32 values. This solution uses 8-bit PORTD for value intended to external D/A converter. The second one solution exploits compare facilities of PIC18F46K22, only two pins of microcontroller are needed for described application. And the third solution is similar to the second, difference consists in exploiting of PWM microcontroller hardware. Presented solutions were created in context of works on dotation program "Support of Science and Research in Moravia-Silesia Region"
Jitter elimination at optical control of servomotors
The article describes the application of microcontroller PIC18F25K22 to servomechanism electronics built – in the model of car. Model is controlled optically, in the infrared part of the spectrum. Used microcontroller is optimal for this application – it has timers with capture facilities, sufficient number of PWMs, powerfull instruction set. The main task for microcontroller is to process incoming PWM signals S1, S2 (having jitter) into output PWM signals P1, P2 (jitter free). The P1 controls the angle of wheels, and the P2 handles the speed. Values of incoming signals are continuously summarized and rounded. There was choiced method of hysterezis in sophisticated algorithm for setting output PWM signals P1, P2 using tables of duties
Software as a Service
Cílem této bakalářské práce je seznámit se s modelem Software jako služba a implementovat informační systém využívající tento model. Zvolený model byl implementován jako systém pro správu úkolů a projektů. Teoretická část práce se zabývá tématem Software jako služba a je provedena analýza možností architektury. Praktická část práce popisuje implementovaný informační systém demonstrující aplikaci modelu Software jako služba, kde je také provedena datová a funkční analýza. Závěr práce je věnován porovnání s již existujícími systémy s podobnou funkcionalitou, implementaci konkrétních funkcí v systému a grafickému rozhraní.The goal of this bachelor thesis is to become acquainted with model Software as a Service and to implement an information system using this model. Model was implemented as task and project management system. The theoretical part delas with topic Software as a Service and contains analysis of architecture options. The practical part of the thesis contains description of the implemented system demonstrating model Software as a Service followed by data and function analysis. The end of thesis is devoted to comparison with existing systems with similar functionality, to system development including chosen functions and to user interface.460 - Katedra informatikyvýborn
Time Series, Cyclical Behavior and Technical Analysis for Automated Trading
Tato diplomová práce se zabývá analýzou časových řad a využití jejich výsledků pro automatické obchodování na burze kryptoměn. V práci je popsána teorie časových řad včetně metod a nástrojů pro analýzu časových řad. Práce obsahuje úvod do světa kryptoměn a zásady obchodování na burze. Praktická část se zabývá infrastrukturou pro práci s daty k automatickému obchodování s kryptoměnami. Na ni navazuje analýza časových řad, která poskytuje systému predikce vývoje cen. Systém pro automatické obchodování byl implementován v rámci týmového projektu. Pro implementaci analýzy byl využit primárně programovací jazyk Python.This thesis deals with the analysis of time series and the use of their results for automated cryptocurrency trading. The thesis describes time series theory including methods and tools for time series analysis. The thesis includes an introduction to the world of cryptocurrencies and the principles of exchange trading. The practical part deals with the infrastructure for working with data for automated trading, which is followed by time series analysis, which provides a price prediction to the system. The system for automatic trading was implemented as part of a team project. The Python programming language was used to implement the analysis.460 - Katedra informatikyvýborn
Systém řízení kvadrokoptéry
Cílem této diplomové práce je provedení návrhu systému řízení kvadrokoptéry, implementace jeho algoritmů na mikrokontrolér STM32 a navržení vlastní řídicí desky se zmíněným mikrokontrolérem. V úvodní teoretické části jsou vysvětleny základní termíny z řešené problematiky, je představen princip fungování regulátorů PID respektive PSD a probrán potřebný matematický aparát, nutný k pochopení principů, představených v následující části práce. V ní je provedena rešerše metod vyhodnocování orientace kvadrokoptéry, na základě které je jedna z metod vybrána. Část následující je věnována regulaci letu kvadrokoptéry a popisu vybraného řešení na bázi regulátorů PSD. V další části je představena rodina mikrokontrolérů STM32 a vybrán konkrétní mikrokontrolér a vývojová deska. Následující kapitola popisuje návrh elektronického obvodu vlastní řídicí desky, na základě kterého je v další kapitole proveden návrh desky plošných spojů. Po představení výsledků výroby navržené desky je v následující kapitole popsána implementace algoritmů zvoleného systému řízení na vybraný mikrokontrolér. V části poslední jsou představeny výsledky této implementace.The aim of this thesis is to design a quadcopter control system, implement its control algorithms on STM32 microcontroller and design a custom flight control board based on the mentioned microcontroller. The initial theoretical part explains the basic terms of the discussed problems, describes the principles of operation for the PID and PSD controllers and presents the necessary mathematical apparatus needed to understand the principles presented in the following part. In it a review of methods for evaluating quadcopter attitude is presented, on the basis of which one of the method is selected. The following section is dedicated to the quadcopter flight control and the description of the selected solution based on PSD controllers. In the next section, the STM32 microcontroller family is introduced and a specific microcontroller and development board is selected. In the next section, the electronic circuit design of the custom flight control board is performed with respect to the selected microcontroller. The following section describes the PCB design procedure for the proposed electronic circuit. After presenting the manufacturing results of the designed board, the next section describes the implementation of the algorithms of the selected control system to the selected microcontroller. The last section presents the results of implementation.1
Secondary zircon-group minerals originating by recrystallization of Sc,Y,U,P-rich zircon and complex WNb-Fe-Sc oxide from the pegmatite No. 3, Dolní Bory, Czech Republic
Optimisation of lab-scale continuous alcohol-free beer production
In order to study the formation and conversion of the most important flavour compounds, the real wort used in alcohol-free beer fermentation was mimicked by a complex model medium containing glucose, yeast extract, and selected aldehydes. The fermentation experiments were carried out in a continuously operating gas-lift reactor with brewing yeast immobilised on spent grains (brewing by-product). During the continuous experiment, parameters such as oxygen supply, residence time (Rt), and temperature (T) were varied to find the optimal conditions for the alcohol-free beer production. The formation of ethanol, higher alcohols (HA), esters (ES), as well as the reduction of aldehydes and consumption of glucose were observed. The results suggest that the process parameters represent a powerful tool in controlling the degree of fermentation and flavour formation brought about by immobilised biocatalyst. Subsequently, the optimised process parameters were used to produce real alcohol-free beer during continuous fermentation. The final product was compared with batch fermented alcohol-free beers using the methods of instrumental and sensorial analysis.Ministry of Education, Youth and Sports of the Czech Republi
Preparation of textured surfaces on aluminum-alloy substrates
The ways of producing porous-like textured surfaces with chemical etching on aluminum-alloy substrates were studied. The most appropriate etchants, their combination, temperature, and etching time period were explored. The influence of a specifically textured surface on adhesive joints' strength or superhydrophobic properties was evaluated. The samples were examined with scanning electron microscopy, profilometry, atomic force microscopy, goniometry, and tensile testing. It was found that, with the multistep etching process, the substrate can be effectively modified and textured to the same morphology, regardless of the initial surface roughness. By selecting proper etchants and their sequence one can prepare new types of highly adhesive or even superhydrophobic surfaces. © 2018 by the authors.Ministry of Education, Youth, and Sports of the Czech Republic-Program NPU I [LO1504]; European Regional Development Fund [CZ.1.05/2.1.00/19.0409]; TBU grant [IGA/FT/2017/011, IGA/FT/2018/011
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