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The forensic analysis of soil by FTIR and NIR with multivariate analysis
Nawrath, Pavel ; Kučerík, Jiří (referee) ; Doležalová Weissmannová, Helena (advisor)
This diploma thesis is about forensic multivariate soil analysis in the localities Ostrava and Třinec. A total of 52 samples were taken in the areas near metallurgical companies. These samples were measured for concentrations of chromium, manganese, copper, nickel, lead, mercury and zinc. Mercury concentration was analysed using AMA 254 device. The remaining metals were determined by flame atomic absorption spectrometry (F–AAS). Additionally, IR spectra were acquired by Fourier transform infrared spectroscopy (FTIR) using diffusion reflectance technique (DRIFT). In the end the results were used to create correlation models and statistical models of PCA (principal component analysis) methods with CA (correlation analysis).
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Development of universal software interface for detection units in optical spectroscopy
Belica, Martin ; Pořízka, Pavel (referee) ; Žalud, Luděk (advisor)
This master's thesis deals with the design and implementation of universal user interface for detection devices used in Laser-induced breakdown spectroscopy. The design and implementation are based on analysis of current state of instrumentation used in laser spectroscopy. The user interface should be able to work with high repetition frequency of measurement. Acquired spectra should be visualised to user and it is also necessary to save this data on hard drive. The resulting application must be universal. It means the application must support various types and vendors of detection devices.
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Properties of faint meteors studied by video observations
Vojáček, Vlastimil ; Borovička, Jiří (advisor) ; Campbell-Brown, Margaret (referee) ; Tóth, Juraj (referee)
Parallel double-station video observations paired with spectroscopic video observations are a good way to study millimetre-sized meteoroids. Almost two decades of video observations of meteors at the Ondřejov observatory give us broad database to study large quantities of meteoroids and their properties. In this work we combined spectral video observations and results of the modelling of the fragmentation of meteoroids. Along with complex infor- mation about meteoroid's trajectories and orbits, this can give us better understanding about origin, internal structure etc. of these millimetre-sized interplanetary bodies. Meteoroids that contained small grains tend to release the sodium early. Since there is a smaller amount of sodium for Na depleted meteoroids, the sodium was released earlier than it was released for meteoroids with same grain sizes and without the sodium depletion. Overall, meteoroids with sodium depletion showed different composition: they were composed of stronger material without very small grains and they did not showed very bright wakes. Two iron meteoroids on Halley type orbits were observed. They are probably remnants of complicated early years of our solar system. The dis- tribution of grain sizes of Jupiter-family members was in a good agreements with results from the COSIMA...
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Optimalozace generace superkontinua v UV až blízké IR oblasti
HOROVÁ, Nikola
Supercontinuum generation occurs when a laser pulse with high intensity passes through an optical medium. The white light is a combination of several nonlinear effects and thus depends on the various parametres. The main task of this bachelor thesis is to find parametres (a focal length, energy of pulse, a diameter of an aperture) for the white light generation in the UV through near IR region in 2-3mm thin crystal plates of sapphire, quartz and YAP.
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Monitoring land cover changes using satellite high temporal resolution data
Indrová, Magdalena ; Lysák, Jakub (referee) ; Štych, Přemysl (advisor)
The objective of this work is to create a base of spectral characteristics of the monitored vegetation types and to create a classification of the land cover. In this work MERIS images obtained by KAGIK were used. Ten different categories of land cover were selected for the study. The spectral behaviour of all categories for the period April - November 2009 was determined. The spectral response of some defined categories (coniferous forests, developed areas) was stable during the year. Contrary to that, significant changes in the spectral response of agricultural crops were observed. The best results were obtained in the categories Forests and Oilseed rape. Finally, the method of Spectral Unmixing was also tested. This method is used when some pixels contain several cover types. Using this method the best result was also obtained in the category Forests. It is evident that the MERIS images can be used for monitoring land cover changes, but because of the coarse resolution only large and homogeneous areas can be studied.
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Unfolding of energies of fusion products measured by the activation probe at JET
Ficker, Ondřej ; Mlynář, Jan ; Bonheure, G. ; Murari, A. ; Popovichev, S.
Providing a detection method for diagnostic of charged fusion products in tokamaks presents a major challenge, while its absolute calibration with a sufficient accuracy and its capability to withstand harsh fusion reactor environment will be required. A novel type of detector that meets most of these requirements, based on an activation probe, was tested in JET and other European facilities. This probe proved to be extremely robust due to its simple construction. It is equipped with samples of well defined isotopic abundance. The amounts of activated nuclei due to the reactions in these materials could be measured via ultra-low-level gamma spectroscopy. The feasibility of the proton spectrum reconstruction from measured activities is examined in this contribution with the help of the algorithm based on the Tikhonov regularisation constrained by minimum Fisher information. The reliability of the method was previously illustrated using synthetic proton data.
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Finite element modelling of voice propagation through the vocal tract and around the human head
Tomeček, Vojtěch ; Pellant, Karel (referee) ; Švancara, Pavel (advisor)
This diploma thesis deals with creating of finite element model for the analysis of acustic waves radiation through human vocal tract and through the head surrounding space. The thesis contains a short overview of the anatomy of relevant parts and a short overview of formerly published models relevant to the topic. Then the process of creating the 3D model of human head, including the vocal tract, based on CT scans, and the mesh itself follows. This is succeeded by the computational solution taking in the acount the acoustic absorption of the vocal tract walls and radiation into the open space. The results gained are compared to relevant literature on this topic. The changes in frequency spectra in specific nodes of the mesh are reviewed and compared to relevant literature on the topic. The results could be used as basis of eventual frequention corrections of microphones used for voice diagnosis or registration in general, eg of speach or singing.
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Non-invasive Blood Glucose Measuring
Vítová, Hana ; Chmelař, Milan (referee) ; Sekora, Jiří (advisor)
Goal of my master´s thesis is examination of non-invasive blood glucose measurement methods, and designing of device for non-invasive blood glucose reading. The introductory chapter of thesis contains description of know different methods for blood glucose measurement, mainly Near Infra-Red region (NIR) measurement with spectroscopy methods. This project describes pathology of Diabetes Mellitus, specifies how it is divided, and looks also on human metabolism. The theoretical part contains exploration of blood glucose measurement methods. Thesis continues with system scheme design for non/invasive glucose measurement device, based on present knowledge. Major principle of device is measuring with Infra-Red laser, bifurcate optic fiber and photodiode. Design of printed circuit board is also present. Document contains also designs of software diagrams for calibration and processing program written in C# language. Communication between device and computer is made via USB. Microcontroller with C language program is part of designed device. It is used to send measured values into PC and also receives data from computer. This data determines blood glucose concentration and their thresholds.
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Real time noise reduction
Koula, Ivan
Algorithms enhancing the useful audio signal at the expense of background interference noise have become a topical problem. Most important of all is to improve methods working in real time. These methods come in useful especially in area of mobile communications.
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