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Stárnutí obyvatelstva a jeho důsledky ve městě Přerově
Calábková, Zuzana
The bachelor thesis deals with the aging of the population of the town of Přerov and associated the growing need of social services for elderly. In the first part of bachelor thesis is an analysis of selected demographic indicators in the town of Přerov and prediction of their development using the extrapolation of time series. Second part deals with evaluation of capacity of social services for elderly in Přerov and in the close surroundings of the Přerov.
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Testing of Surge Arresters
Jeřábek, Lukáš ; Paar, Martin (referee) ; Krbal, Michal (advisor)
This bachelor's thesis is devoted to metal oxide surge arresters. After historical and theoretical introduction, which explains their principles and describes their characteristical properties, analysis of the standard IEC 60099-4 and testing according to the standard with focus on the type tests follows. This chapter is also amended with review of the standard's imperfections and with its most probable future development. The work concludes with a market survey, a review of the largest manufacturers and a comparison of their products.
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Thermal degradation of alternative electrical insulating liquids
Vodička, Tomáš ; Kazelle, Jiří (referee) ; Frk, Martin (advisor)
This thesis deals with alternative thermal degradation of electrical insulating liquids. The theoretical part describes the current state of the problem, electrical insulating liquids, their classification and types. There are described properties of electrical insulating liquids, their models of aging and diagnostic methods in accordance with the appropriate standards. In the practical part are chosen by representatives of alternative electrical insulating liquids and there are determined their dielectric characteristics in the initial state. According to the measured values is chosen five candidates for which it is designed and implemented an accelerated degradation test. During the test are measured dielectric parameters of the selected oils. Measured dependencies are mathematically approximated. In conclusion, the results are compared and physically interpreted in view of oxidation stability.
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Ageing of asphalt binders
Střasáková, Monika ; Hegr, Zdeněk (referee) ; Dašek, Ondřej (advisor)
The theoretical part of this thesis describes the rheology of bituminous binders, aging of asphalt binders and laboratory methods simulating short and long term aging. The following describes an empirical tests (needle penetration, softening point ring ball method) and functional tests (complex shear modulus and phase angle, dynamic viscosity), which are performed in the dynamic shear rheometer. At the end of this section, laboratory aging of bituminous binders using method RTFOT and method RTFOT + PAV is described in more detail. In the practical part of this thesis, the results of all tests performed on the binders aged using RTFOT + PAV are introduced and compared with results of properties of non-aged binders and binders aged by 3xRTFOT.
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Analysis of ageing of selected materials used in sewage systems
Horák, Marek ; Stanko,, Ing Štefan (referee) ; Tlolka, Jan (referee) ; Raclavský, Jaroslav (advisor)
The doctoral thesis deals with analysis of the ageing of concrete and reinforced concrete pipes in sewage systems. The ageing of the sewage system is caused by several reasons, for example material abrasion, chemical and biological corrosion and subsequent static overload sewer construction. One of the common causes of degradation of sewage systems made from materials bonded with cement sealant is biogenic sulphate corrosion. Due to the corrosion the degradation of the pipe walls accelerates, particularly in upper part of the pipe and reduces planned lifetime of the sewage system. There is proposed new ageing analysis monitoring method for observation and evaluation of the loss of thickness of concrete and reinforced concrete pipes, which is caused by biogenic sulphate corrosion. Residual lifetime is calculated from the expected corrosion rate, it`s the loss of wall thickness on the monitored section of the sewer system. There is designed the monitoring system of the loss of wall thickness on the sewage system for practical application of the measurement procedure, which is administrated in cooperation with the BVK, a. s. The thesis uses existing knowledge regarding this subject. We use this information for better understanding of the process of the loss of wall thickness in sewage systems in real time and the posibility to correct and in-time implementation of appropriate operational measures. This should cause the limitation of the degradation process of piping material while extended service life and safe operation in sewage systems within the required time period. Based on the methodology is proposed to determine the residual life of the sewage system and maintenance and rehabilitation can be done more effectively. There is needed to be noted that only long-term monitoring period can bring a better overview of the technical condition of sewage systems in time and thus better and more effective maintenance and rehabilitation, which is related to the effective u
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Study of Scattering and Polarization of Light in Biological Tissue
Abubaker, Hamed Mohamed ; Hrabovský, Miroslav (referee) ; Číp, Ondřej (referee) ; Tománek, Pavel (advisor)
Tkáňová optika nabývá rychle na významu a přesná znalost optických vlastností biologických tkání je podstatná pro výzkum v biomedicíně i pro kontrolu kvality potravin. Jestliže je vzorek tkáně osvětlen, dochází k mnohonásobnému odrazu světla. V případě postmortem neživých tkání (maso) je rozměr buněk větší než vlnová délka použitého světla. Dochází k Mieovu rozptylu prošlého nebo zpět odraženého světla, v důsledku čehož se objevují různé polarizační stavy světla. Polarizační stavy světla rozptýleného na difúzním prostředí jsou experimentálně zkoumány a modelovány. V práci jsme provedli dva modifikované experimenty: rozptyl polarizovaného světla, které dvakrát prochází vzorkem (vpřed a vzad) a jen světla, které jen prochází vzorkem. Měření rozptýleného světla ukazuje, že dochází k depolarizaci a ke stáčení polarizační roviny, což obojí závisí na orientaci svalových vláken a stárnutí tkání postmortem. Mimo experimentů byl také proveden teoretický popis difúzní biologické tkáně a byla vypočtena radiační přenosová rovnice pomocí modifikované Monte Carlo metody, která zahrnuje polarizační stav světla (PLMC). Je ukázáno, že stupeň polarizace podstatně závisí na optických vlastnostech rozptylového prostředí. Výsledky ukazují, že stav polarizace světla na výstupu závisí na stavu polarizace světla před vzorkem a na optických vlastnostech a tloušťce vrstvy prostředí v průběhu jejího stárnutí. Je také provedena korelace změn polarizace na čerstvosti masa, i popis dynamického chování polarizace při stárnutí masa.
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Rheological properties of asphalt binders
Pěnčík, Michal ; Mondschein,, Petr (referee) ; Hýzl, Petr (advisor)
The Diploma thesis is focused on rheological properties of bituminous binders and mixtures. Above all, it describes the changes of these properties of samples of bituminous binders and mixtures. Those were brought by the process of laboratory aging, since it simulates the changes occurring in the in the real-life conditions. The theoretical part depicts the field of rheology and methods utilized for simulating the ageing of binders and mixtures. The practical part describes the process of preparation of samples and its testing. Firstly, the ageing of bituminous mixture by the means of BSA method (Braunschweiger Alterung) took place, which was followed by preparing the solids for testing the modulus of stiffness and main testing. The rest of the mixture was used for extracting the binder. Tests with the binder were focused on the usage of dynamic shear rheometer (complex shear modulus, dynamic viscosity). The last part of the work is dedicated to the comparison of the outcomes of testing.
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Ageing of asphalt binders and mixtures
Štěpanovský, Vlastimil ; Komenda, Radek (referee) ; Hýzl, Petr (advisor)
Diploma thesis is particularly focused on ageing of asphalt mixtures and asphalt binders. In the theoretical part an array of methods simulating short term and long term ageing consequently is introduced. The main objective of the practical part was to carry out the long-term ageing test method BSA (Braunschweiger Alterung). Thereafter, specimens testing for stiffness properties according to CSN EN 12697-26 were made. After conducting the measurement on those, asphalt binder was extracted and processed to follow-up testing. The testing consisted of a range of methods – Penetration CSN EN 1426, Ring and Ball test CSN EN 1427, Determination of the Frass breaking point CSN EN 12593, Determination of complex shear modulus CSN EN 14770 and Dynamic viscosity using a dynamic shear rheometer (DSR). The given results were assessed in the last part in order to evaluate the rate of the binder degradation caused by the method BSA.
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Rheological properties of binders
Hotař, Petr ; Fišer,, Jiří (referee) ; Kudrna, Jan (advisor)
The comparison of rheological properties (complex shear modulus and phase angle and dynamic viscosity) of four paving bitumens and two polymer modified bitumens is performed in this diploma thesis. Furthermore, the empirical tests (needle penetration and softening point) were determined on these binders. Effect of asphalt binders aging was modeled using RTFOT test and modified RTFOT test (3 x RTFOT).
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Resistance of bituminous binder to ageing
Rous, Vojtěch ; Frýbort, David (referee) ; Kudrna, Jan (advisor)
Asphalt binder ageing and experiences with various ageing methods from abroad are described in this thesis. The practical part deals with the RTFOT aging and with the influence of the duration of this test. The comparison of test results is conducted before and after the aging by values of needle penetration, elastic recovery, softening point and resilience tests are evaluated and compared.
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