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Usage of Modern Methods for Increasing Reliability of Control System Implementations
Szurman, Karel ; Mičulka, Lukáš (referee) ; Kaštil, Jan (advisor)
At avionics control and critical systems is necessary guarantee a minimal level of fault tolerance and their high reliability. On the electronic components in these devices has an undesirable influence environment conditions and mainly cosmic ray. In this paper are described the most common failure types of semiconductor components and devices together with modern methods which can be increased the system fault tolerance and its overall reliability. There are introduced aspects of the avionic systems design due to finally certification and ways to evaluate its safety. This thesis describes design and implementation of the CAN bus control system for the FPGA platform which uses the CANAerospace application protocol. Created system design is improved by the TMR architecture. Fault tolerance of both system version is tested by the SEU framework which allows using the dynamic partial reconfiguration generate an SEU failures into running FPGA design.
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Methodology of highly reliable systems design
Straka, Martin ; Gramatová, Elena (referee) ; Racek, Stanislav (referee) ; Kotásek, Zdeněk (advisor)
In the thesis, a methodology alternative to existing methods of digital systems design with increased dependability implemented into FPGA is presented, new features which can be used in the implementation and testing of these systems are demonstrated. The research is based on the use of FPGA partial dynamic reconfiguration for the design of fault tolerant systems. In these applications, the partial dynamic reconfiguration can be used as a mechanism to correct the fault and recover the system after the fault occurrence. First, the general principles of diagnostics, testing and digital systems dependability are presented including a brief description of FPGA components and their architectures. Next, a survey of currently used methods and techniques used for the design and implementation of fault tolerant systems into FPGA is described, especially the methods used for fault detection and localization, their correction, together with the principles of evaluating fault tolerant systems design quality. The most important part of the thesis is seen in the description of the design methodology, implementation and testing of fault tolerant systems implemented into FPGAs which uses SRAMs as the configuration memory. First, the methodology of developing and automated checker components design for digital systems and communication protocols is presented. Then, a reference architecture of a dependable system implemented into FPGA is demonstrated including several fault tolerant architectures based on the use of partial dynamic reconfiguration as the mechanism of fault correction and the recovery from it. The principles of controlling the reconfiguration process are described together with the description of the test platform which allows to test and verify the design of fault tolerant systems based on the methodology presented in the thesis. The experimental results and the contribution of the thesis are discussed in the conclusions.
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Utilization of artificially created weak magnetic field for navigation in 3D space
Váňa, Dominik ; Beneš, Petr (referee) ; Havránek, Zdeněk (advisor)
This master's thesis focuses on the utilization of an artificially created weak magnetic field for navigation in 3D space. The theoretical part of this work deals with the general properties of the magnetic field and with its description. The next section of the theoretical part contains an overview of measuring principles for magnetic field measurements. Based on various types of measuring principles, the thesis elaborates on commercially available miniature sensors for magnetic field measurement with a measuring range up to 10 mT. The work focuses mainly on the magnetoresistive principle and fluxgate sensors. Furthermore, the theoretical part contains descriptions of methods for modeling the magnetic field of simple permanent magnets and various magnet assemblies. Lastly, the theoretical part involves a patent search of devices used for locating magnets that are installed in an intramedullary nail, which is used in intramedullary stabilization used on fractures of human bones. By locating the magnet in the nail, it is possible to precisely determine the position of the mounting holes. The practical part of the thesis deals with the analysis of magnetic field behavior in the vicinity of various magnetic assemblies, which were modeled in COMSOL Multiphysics using the finite element method. The models were created with the aim of analysing the behaviour of the magnetic field in the vicinity of the magnets and at the same time to find possible analytical functions that could be used to determine the position of the magnet in space relative to the probe. The result of this work is an analysis of various assemblies, which contains graphs of different dependencies and prescription of polynomial functions that approximate these dependencies. Another part of the thesis is the design of a probe that serves to locate the magnetic target. The work describes two possible methods of localization. For the differential method, a user interface in LabVIEW was created. The probe based on this method is fully capable of locating the magnet in the 2D plane. The state space search method is described only in theory.
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Methodology for fault tolerant system state synchronization design and its recovery from faults
Szurman, Karel ; Fišer, Petr (referee) ; Racek, Stanislav (referee) ; Vlček, Karel (referee) ; Kotásek, Zdeněk (advisor)
In this Ph.D. thesis, a new methodology for the fault tolerant system state synchronization design and its recovery from faults is presented. A state synchronization method designed by means of the proposed methodology allows to repair the state of sequential logic elements implemented in the FPGA application logic, which cannot be repaired by the partial dynamic reconfiguration. The proposed methodology describes possible state synchronization design methods with respect to TMR granularity, dependence of the system function on its previous states and the system architecture. The methodology focuses on coarse-grained TMR architectures and state synchronization in the systems controlled by means of finite state machines or a processor. The use of the methodology is demonstrated on the CAN bus control system and the microcontroller NEO430, for which specific synchronization methods were designed. The systems reliability and new ability of the systems for recovery from faults were verified in the presence of simulated SEU faults. The experimental results and the contribution of this thesis are discussed in the conclusion.
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Cell labeling with magnetic particles
Kukhta, Dziyana ; Janoušek, Oto (referee) ; Čmiel, Vratislav (advisor)
This bachelor thesis describes the movement of cells labelled with magnetic nanoparticles in the magnetic field in the direction of the magnet. First, it describes two types of magnets: permanent magnet and electromagnet. Then, it is dedicated to magnetic field sensors, magnetic nanoparticles and their incorporation in cells, optical systems for detecting cell movement and the effect of electromagnetic fields on cells. The practical part is dedicated to the incorporation of nanoparticles in cells, the measurement of the magnetic field intensity of a neodymium magnet and an electromagnet, and the methods of electromagnet control. It also describes the effect of electromagnetic fields on fibroblasts and the concentration of nanoparticles on the ability of the labelled cells to react to a magnetic field. The last part is dedicated to the production of a flow chamber, the analysis of the movement of cells in the chamber and the subsequent capture of cells in various magnetic fields.
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Magnetic multilayers for spintronics applications
Vaňatka, Marek ; Dvořák, Petr (referee) ; Urbánek, Michal (advisor)
Magnetic multilayers have applications as magnetic field sensors or magnetic memory cells. Mastering the methods of fabrication and characterization of the structures such as spin valve or magnetic tunnel junction is an important step towards more complicated spintronics devices. This work summarizes basic theory of magnetism, magnetotransport properties, and it describes basic applications of magnetic multilayers. The experimental part of this work deals with the sample preparation by ion beam sputtering (IBS), ion beam assisted deposition (IBAD), and characterization of prepared multilayers by measuring anisotropic magnetoresistance (AMR), giant magnetoresistance (GMR), or tunnel magnetoresistance (TMR).
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Stanovení in vitro stravitelnosti sušiny a organické hmoty směsných krmných dávek s rozdílným zastoupením krmných surovin
Ursová, Lucie
The aim of this thesis was evaluvation of the digestibility of dry matter and organic matter by in vitro method in total mixed ration (TMR) with different representation of components. The gastrointestinal tract of ruminants with all its physiological requirements is described in the literary review. Furthermore, attention was paid to factors affecting the digestibility of feed and subsequent methods for determination of digestibility. The literary review was also focused on the characteristics and structure of TMR. TMR analyzes were determined by chemical methods and subsequently statistically evaluated in Excel and Statistica. The analysis took into account the chemical analysis, nutritional value and concentration of macroelements and microelements. 8 TMRs with different proportions of components were selected for analyzes, of which 6 were assembled for the peak of lactation, one for early lactation and one for the end of lacta-tion. All TMRs are designed for dairy cows with production capacity of over 9,000 l of milk.
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Non-pharmacological methods for influencing memory consolidation during sleep
Němcová, Monika ; Kopřivová, Jana (advisor) ; Honc, Ondřej (referee)
Sleep plays vital role in many physiological processes of the human body, including the consolidation of memory. The beneficial effects of sleep on memory consolidation have long been known, but only in the last two decades the knowledge of the relationship between sleep and memory has been used to develop interventions to improve memory consolidation during sleep. Two of these approaches are the focus of this work: closed-loop auditory stimulation (CLAS) and targeted memory reactivation (TMR). They are of particular clinical interest, as they are non- pharmacological, which minimizes the risk of dependence and abuse. In addition, they do not impose exogenous force fields on the brain and are, therefore, considered safer than other similar interventions. The aim of this work is to describe CLAS and TMR in detail, to investigate which factors influence their efficacy, and to discuss their clinical potential in the treatment of memory- related disorders.
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Vliv kvality kukuřičné siláže na mléčnou užitkovost dojnic
BRÁCHA, Daniel
With the ever-increasing demands on milk yield, it is necessary that the present feed is of the highest quality and contains the required nutrients. To fulfill these requirements, the bulk feeds produced, especially maize silage, must be healthy and of the highest quality. The bachelor thesis was divided into two parts. In the first, thus theoretical part, are generally discussed about the silage process and related terms, such as ensilability or silage. However, the majority part of it is devoted to technological silage processes. Following these processes means healthy and high-quality feed. These processes include mainly covering, compactining, filling silage pits and more. From a qualitative point of view, it is important to control the dry matter content, the length of the cut and the degree of grain crushing. Failure of following the recommended the optimal values may mean a degradation of the fermentation process or the occurrence of undesirable microorganisms in the final feed. In a result, the utility and reproductive properties are worsen. The health of the animals may also be worsen. Preservatives can be used to improve the fermentation process and keeping constant aerobic stability during feeding. The end of the theoretical part is devoted to nutrition and feeding techniques of dairy cows, specifically mixed feed ration (TMR), rumen fermentation and milk yield. The practical part was carried out on a dairy farm in Pernarec, which is part of the Úněšovského statku a.s., which agricultural in the northern part of Plzeň. Here were evaluated the annual milk yields and the factors that influence them. The majority part is devoted to the analysis of corn silage and the preparation of TMR. Next were evaluated the qualitative composition of silages and the precision of TMR preparation in relation to the economics of milk production. The possible effect of the weather on milk yield and quality of corn silages was also taken account. Monitored and evaluated were data in the years 2018 - 2021.
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Methodology for fault tolerant system state synchronization design and its recovery from faults
Szurman, Karel ; Fišer, Petr (referee) ; Racek, Stanislav (referee) ; Vlček, Karel (referee) ; Kotásek, Zdeněk (advisor)
In this Ph.D. thesis, a new methodology for the fault tolerant system state synchronization design and its recovery from faults is presented. A state synchronization method designed by means of the proposed methodology allows to repair the state of sequential logic elements implemented in the FPGA application logic, which cannot be repaired by the partial dynamic reconfiguration. The proposed methodology describes possible state synchronization design methods with respect to TMR granularity, dependence of the system function on its previous states and the system architecture. The methodology focuses on coarse-grained TMR architectures and state synchronization in the systems controlled by means of finite state machines or a processor. The use of the methodology is demonstrated on the CAN bus control system and the microcontroller NEO430, for which specific synchronization methods were designed. The systems reliability and new ability of the systems for recovery from faults were verified in the presence of simulated SEU faults. The experimental results and the contribution of this thesis are discussed in the conclusion.
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