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Improvement of control and analysis techniques of a SPM model
Štefko, Marcel ; Nováček, Zdeněk (referee) ; Šulc, Dalibor (advisor)
Bakalářská práce se zabývá zdokonalováním výukového modelu mikroskopu atomárních sil (AFM). Součástí práce je rešerše stávajících analogii mezi makroskopickými jevy a fenomény spojenými s mikroskopii rastrovací sondou. Dále byla vybrána vhodná analogie, která byla následně implementována do již existujícího modelu mikroskopu atomárních sil. Do modelu byl integrován i jednodeskový počítač, který zajistí ovládání i bez nutnosti připojení externího počítače. Na závěr byly vyhodnoceny vlastnosti použité sondy a analogie mezi modelem a skutečnými mikroskopy atomárních sil.
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Correlated probe and electron microscopy for the study of modern magnetic nanomaterials
Novotný, Ondřej ; Flajšman, Lukáš (referee) ; Pavera, Michal (advisor)
High pressure on the development of new magnetic materials and their miniaturization also emphasizes the development of new analytical techniques. This diploma thesis deals with the development and demonstration of correlated magnetic force and electron microscopy, which is a promising tool for the characterization of magnetic nanomaterials. The first part of this thesis describes the fundamental physics of micromagnetism with a focus on cylindrical nanofibers. The following pages describe optic, probe, electron, and synchrotron methods for mapping the magnetic properties of materials. The next part describes magnetic domain wall motion in cylindrical nanowires performed as a part of a more extensive material study. The last part of the thesis describes the development of correlated magnetic force and electron microscopy on LiteScope device. A production of magnetic probes was designed and successfully tested. Probes were fabricated by focused electron beam-induced deposition from the Co2(CO)8 precursor. Further, the developed correlated microscopy is demonstrated on a multilayer PtCo sample, magnetic cylindrical nanofibers, NiFe vortex structures, and FeRh metamagnetic nano-islands.
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Software for patients and brain regions selection suitable for analysis of connectivity in fMRI
Slavíček, Tomáš ; Lamoš, Martin (referee) ; Jan, Jiří (advisor)
The aim of this thesis is to create an exploratory tool for functional magnetic resonance imaging data, which allows quickly and easily making a selection of persons and areas suitable for group analysis of connectivity. In the first chapters of this work is mentioned history of brain research and comparison of methods used in functional imaging. Next they are discussed the theoretical basis of fMRI methods, such as the formation of BOLD signal, acquisition parameters of MRI images and methods for designing experiments. The following chapter describes in detail the analysis of recorded data from the pre-processing to the interpretation of results. The last chapter of the first part describes problems of group analysis in SPM8 software. The second half of this work is dedicated to the description of developed program from data input to saving the results, including detailed descriptions of key features. In conclusion, there is a chapter characterizing the application of developed program on real data from clinical studies, including the results and evaluation of the usability of program. The program will mainly be used in neuroscience research.
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Visualization and export outputs from functional magnetic resonance imaging
Přibyl, Jakub ; Gajdoš, Martin (referee) ; Slavíček, Tomáš (advisor)
Thesis discusses the principles and methodology for measuring functional magnetic resonance imaging (fMRI), basically the origin and use of BOLD signal types used experiments. Further attention is paid fMRI data processing and statistical analysis. Subsequent chapters are devoted to a brief description of the most common software tools used to analyze data from fMRI. The main section was to create a program in MATLAB with a detailed graphic user interface for easy visualization and export output from analyzes of fMRI data. The second half is devoted to describing the program developer and graphic user interface, including key functionality. The final section describes the application program with real data from clinical studies of dynamic connectivity and use in an international project APGem.
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Local electrical conductivity measurements in AFM tapping mode
Dao, Radek ; Konečný, Martin (referee) ; Pavera, Michal (advisor)
This bachelor thesis is concerned about the development of a probe for local electrical conductivity measurements in tapping mode Atomic Force Microscopy. The teoretical part gives a short overview of Scanning Probe Microscopy techniques, with the focus being on Conductivity Atomic Force Microscopy. Furthermore, the measuring regime in which the probe operates is described here, as well as the basic component of the probe, the quartz tuning fork. The experimental part follows the iterative development process, and contains a chapter dedicated to making of very sharp tips. The final chapters describe the preparation of test samples, which were used to prove the functionality of the probe and the measurement of local electrical conductivity itself.
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Design of Low-Temperature Ultra High Vacuum Scanning Probe Microscopes
Pavera, Michal ; Klapetek, Petr (referee) ; Vetushka, Aliaksei (referee) ; Šikola, Tomáš (advisor)
This thesis deals with the development of scanning probe microscopes. Mechanical requirements for microscopes using measuring methods of scanning tunneling microscopy (STM) and atomic force microscopy (AFM) under enviroments of an ultrahigh vacuum (UHV) and variable temperatures are specified. Mechanical designs of two microscopes are discussed and their control electronics described. A special chapter is devoted to description of linear piezo manipulators and mechanical design of these prototypes.
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Use of a special optical fiber in an electron microscope chamber
Černek, Ondrej ; Konečný, Martin (referee) ; Pavera, Michal (advisor)
This bachelor thesis is concerned about the modification of vacuum chamber of the Scanning Electron Microscope VEGA developed by TESCAN Brno s.r.o. in order to implementation of Scanning Probe Microscope. Moreover, it is dedicated to development of apparatus for using hollow optical fiber allowing the guidance of light and various gases on the sample surface placed in the vacuum of electron microscope. By using the hollow optical fiber as a probe of Scanning Probe Microscope, it is possible to work with a tip with specific properties. A brief introduction to Scanning Electron Microscopy and Atomic Force Microscopy is presented in the theoretical part. Furthermore, there is a technique of using optical fibers in Scanning Near-field Optical Microscopy described. Also a problem of vacuum systems, gas flow through the pipe and technique of Gas Injection System is introduced. In the construction part, there are initiated steps in the development of the vacuum chamber and the apparatus allowing the guidance of hollow optical fiber into the chamber of microscope. The experimental part presents the result of measurements obtained by probe of Scanning Probe Microscope with modified optical fiber and gas transmissivity of hollow optical fiber.
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Linear and nonlinear phenomena in optical access networks
Valášek, Martin ; Münster, Petr (referee) ; Šifta, Radim (advisor)
The aim of this thesis is an explanation of the problem linear and nonlinear phenomena in optical access networks. In the first chapter refers to a description of the optical fiber, description of the optical environment and the main part is theoretical and mathematical description of phenomena that operate in optical fibers. It is therefore a specific attenuation, dispersion, phenomena of second and third-order, nonlinear light scattering and solitons. Then there is the dismantling brief overview of the distribution of access networks and their description. The second part deals with specific simulation of these phenomena in the simulation program OptSim 5.2. All connections will be implemented in the block diagram Sample-Mode, in which using appropriate units and setting the right parameters, we will try to confirm the theoretical assumptions of the first part.
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Scanning probe microscopy scanner with high resonant frequency
Krupa, Matyáš ; Dostál, Zbyněk (referee) ; Pavera, Michal (advisor)
The thesis deals with the design of the scanning probe microscopy scanner with a higher resonant frequency. The first part of the thesis is focused on theory as the principle of atomic force microscopy, function of the scanner and its properties. The second part describes the gradual development of a new microscope. The mechanical simulations used to determine the properties of scanners are introduced first. Furthermore, the thesis deals with the design for the x, y axis and then also for the z axis. In conclusion, the final design of a three-axis scanner with a higher resonant frequency is presented.
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Self-sensing SPM probes for measuring electrical properties of materials
Očkovič, Adam ; Vařeka, Karel (referee) ; Pavera, Michal (advisor)
The bachelor's thesis is focused on the modification of probes with an integrated sensor usable for measuring conductivity characteristics of surfaces in atomic force microscopy. The first part presents the theory concerning atomic force microscopy, conductivity measurement and deposition using an ion beam. Furthermore, the method of production and limitation of the use of electrically conductive probes with optically read deflection is described. The practical part presents the main problems of probes with integrated sensors in conductivity measurements. Furthermore, the modification of the probes themselves, the measurements made with these probes and suggestions for improving the properties of the probes are described.
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