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11	Zařízení pro automatizovaná testování řídicích jednotek plynových kotlů / Device for automated testing of gas boiler controllers Kuřímský, Lukáš January 2021 (has links) This diploma thesis deals with the design and implementation of a computer-controlled device for testing gas boiler control units, especially in the development phase. The reason for creating a test facility is the inadequacy of older test systems and the automation of existing testing. The test device in development consists of individual different cards. Each of the cards inserted into the motherboard performs its function in the system. Each of the cards has a special functionality which simulates the real conditions of the developed product. The basis of most cards is a microcontroller with a Cortex-M core, which communicates with the connected computer using the MODBUS protocol on the RS-485 communication interface. All cards on the bus are connected in parallel and behaves as a SLAVE, while the computer behaves as a MASTER and requests data or sends commands to the cards. The cards represent status switches (switching sensors), resistance and analog temperature sensors, PWM inputs and outputs (for simulation of feedback pumps or flow meters with pulse output). The cards also include a flame simulator, which reliably simulates the electrical properties of the flame and at the same time acts as a fan simulator. The input of the control unit is taken care of by the input card, which is intended for digital detection of the voltage presence in the range of 5 to 230 V DC and AC. Simultaneously, a card for connecting the power supply at zero voltage and disconnecting at zero current is created to supply the tested device with alternating voltage. A schematic diagram was designed or simulated for each card, then the function was verified and on this basis the whole card was created, including the microcontroller firmware. The most suitable solution and function of each card is carefully described and evaluated. All the requirements of the assignment within the work were met and the whole test equipment was manufactured and verified in four versions. In the future, the device is ready for the implementation of an automatic flame simulator and other improvements of individual module cards.
12	The modernization of a DOS-basedtime critical solar cell LBICmeasurement system. Hjern, Gunnar January 2019 (has links) LBIC is a technique for scanning the local quantum efficiency of solar cells. This kind of measurements needs a highly specialized, and time critical controlling software. In 1996 the client, professor Markus Rinio, constructed an LBIC system, and wrote the controlling software as a Turbo-Pascal 7.0 application, running under the MS-DOS 6.22 operating system. By now (2018) both the software and several hardware components are in dire need to be modernized. This thesis thoroughly describes several important aspects of this work, and the considerations needed for a successful result. This includes both very foundational choices about the software architecture, the choice of suitable operating system, the threading model, and the adaptation to new hardware with vastly different behavior. The project also included a new hardware module for position reports and instrument triggering, as well as several adaptations to transform the DOS-based LBIC software into a pleasant modern GUI application. Pascal programming language Linux operating system real-time PREEMPT_RT patch Free Pascal compiler Lazarus multi-threading computer controlled measurements false color map refactoring software modernization adaptation layer MS-DOS GPIB IEEE-488 silicon solar cell quantum efficiency LBIC electron recombination serial communication micro-controller ISR incremental encoder lock-in amplifier trans-impedance amplifier triggered measurement Computer and Information Sciences Data- och informationsvetenskap
13	Sintering and slagging of mineral matter in South African coals during the coal gasification process Matjie, Ratale Henry 11 November 2008 (has links) Coals, from mines in the Highveld coalfield, as well as gasification ash samples were characterised, in order to understand the mineralogical and chemical properties of the individual components in the gasification feedstocks. X-ray diffraction of low temperature oxygen-plasma ash indicates that the coals contain significant proportions of kaolinite, quartz and a fluxing elements-bearing mineral (dolomite), plus minor concentrations of illite and other fluxing elements-bearing minerals namely calcite, pyrite and siderite. Of the feed coal, the -75+53 mm size fraction has a high pyrite, and to a lesser extent a high calcite and dolomite content. However, the small proportion of iron-bearing phases (from the reaction between kaolinite and pyrite) in samples taken from the gasifier implies that pyrite contributes minimally to sintering or slagging in this case. Calcite is mainly present in the >1.8 g/cm3 density fraction of the feed coal, whereas dolomite is mainly present in the 1.5-1.8 g/cm3 density fraction, as inclusions or fine cleats in the coal matrix. Electron microprobe analyses of coals from the six different South African mines confirmed that some Ca, Mg, Al, Si, Na, K, Ti and Fe are present in the organic matrix in the coal samples tested in this study, but the amounts of these are small compared with the fluxing elements in minerals. XRD and microprobe analyses indicate that the ash clinker samples taken from the gasifiers contain a number of crystalline high temperature phases, including anorthite, mullite, cristobalite, quartz and diopside. FactSage confirmed that anorthite and mullite are equilibrium phases at elevated temperatures in the ash clinkers and heated rock fragments. Limited reaction takes place between the included coal minerals and the extraneous rock fragments. / Thesis (PhD)--University of Pretoria, 2008. / Materials Science and Metallurgical Engineering / unrestricted Energy dispersive spectrometer X-ray diffraction Electron microprobe Particle morphology Low temperature ashing Pyrolysis Sequential leaching Pyrometallurgy Screening Density separation Coal analysis Coal sintering and slagging Lurgi gasification Coal ash analysis Mineral matter Petrology Scanning electron microscopy (SEM) Quantitative evaluation Macerals Factsage modeling Glass analysis Scanning electron microscopy UCTD

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