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Global phylogeography of the deep-sea fishes
Knězů, Tereza ; Musilová, Zuzana (advisor) ; Vukićová, Jasna (referee)
Phylogeography of deep-sea fish remains poorly explored, largely due to the extreme conditions in which these organisms live and limited technological capabilities for researching these species. The aim of this thesis is to summarize the information known about the phylogeography of deep-sea fish, identify factors influencing population distributions, and connect them on a global scale. The distribution of deep-sea fish populations is influenced by physical, topographic, and hydrographic factors. Their connectivity is driven by the migratory abilities of fish and the utilization of marine currents for their dispersion. Migration is divided into vertical and horizontal. The vast majority of deep sea fish undergo some form of migration, at least during ontogenetic development. The most common is diurnal vertical migration, where fish regularly move to shallower depths at night for feeding. Molecular methods, mainly mitochondrial DNA markers, were used for research to determine the phylogenetic tree of species. The results suggest that the topography of the seafloor is rarely a barrier to the flow of genetic information. Furthermore, the results often refute the hypothesis of isolation caused by the distance between populations. They often exhibit a relatively high rate of panmixia. When speciation...
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Morphological adaptations of spores of ectomycorrhizal fungi and their role in dispersal
Jašková, Eliška ; Janošík, Lukáš (advisor) ; Kohout, Petr (referee)
The spore morphology determines the distance and the substrate on which they land. Recent studies show that colonization of a suitable substrate is more important than long-distance dispersal itself. Spore morphology therefore likely reflects specific ecological requirements of a particular species and is shaped by the selective pressure on their effective dispersal. In the case of ectomycorrhizal fungi, on which the work is focused, an important ecological requirement is a substrate where the spore can find a suitable partner for ectomycorrhiza. The beginning of the thesis is dedicated to a brief characterization of ectomycorrhizal fungi. The main part is divided into the summary of current knowledge about the key morphological features of ectomycorrhizal fungi (fruiting body, spore size, spore shape and cell wall ornamentation) and the specific ways how their spores can be dispersed. In the end, I also mention the possibilities of further research in this area.
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Demonstration kit for fiber optic sensing system
Beránek, Karel ; Klíčník, Ondřej (referee) ; Dejdar, Petr (advisor)
This bachelor thesis focuses on the design and implementation of a~demonstration kit for a~fiber optic sensing system. The thesis includes a~theoretical analysis of optical phenomena such as polarization, dispersion, and interference, which are crucial to understanding the principles of fiber optic sensors. The designed sensing system comprises a~Mach-Zehnder interferometer, a~UP-Board development kit, an external 24-bit sound card, and a~touch display. The practical part of the thesis is focused on the construction of the enclosure using 3D printing, the integration of individual components, the design of a~custom application, and the testing of the system. The results of this work contribute to the development of knowledge in the field of fiber optic sensors and can be utilized in both academic and industrial settings.
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Preparation and characterization of epoxy potting resins modified with nanoparticles
Lednický, Jiří ; Polsterová, Helena (referee) ; Chladil, Ladislav (advisor)
This bachelor's thesis focuses on nanocomposites composed of an organic matrix in the form of epoxy resin and TiO2 filler in the anatase crystallographic structure with dimensions in the order of tens of nanometers. The work is aimed at understanding the issue of nanocomposites, summarizing the results of other studies, and especially at the production and characterization of samples with nanoparticles dispersed using a planetary mill. Furthermore, the effect of the used nanoparticles and dispersion in the planetary mill on the dielectric properties of pure epoxy resin was analyzed.
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Animated Graphics Model
Mikšaník, Martin ; Kučiš, Michal (referee) ; Zemčík, Pavel (advisor)
This bachelor’s thesis deals with demonstrations of infrequently used optical phenomena in computer graphics, specifically fluorescence and dispersion of light. The work also proposes a different approach at working with light, material and its rendering. The resulting design is implemented in the attached interactive demonstration program.
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Dispersion measurements of optical transmissions.
Motúz, Rastislav ; Urban, František (referee) ; Filka, Miloslav (advisor)
This thesis firstly theoretically describes phenomena which appear in optical fiber transmission. The theoretical part of the thesis deals with linear and non-linear phenomena, and later on proceeds to dispersions with a more significant effect on the optical transmission quality. It puts polarization to the centre of the phenomenon called Polarization mode dispersion (PMD), which is the main object of our interest. It leads to a deep PMD description from the point of view of polarization states, limit values, compensation methods, and methods of measurement. The practical part of this thesis deals with a draft of PMD measurement via Fixed Analyzer method. For the purposes of this measurement, we used the optical spectral analyzer MS9740A. In order to compare measured values, the proposed idea then proceeds to the reference measurement by using a modular platform EXFO FTB--200 in combination with CD/PMD module EXFO FTB-5700. Results of measurements have been evaluated for the limit values defined by the standard. In the last chapter of this thesis, the reference measurements are compared to the Fixed Analyzer method. All the advantages and disadvantages of individual measurement methods are identified at the end of this chapter too.
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The audit methology of optical networks
Štěpán, Petr ; Münster, Petr (referee) ; Reichert, Pavel (advisor)
This work deals with summary of optical system audit in the terms of all layer of the reference model ISO/OSI. Introduction of the work focuses on exploring issues of management networks control, the description of ISO/OSI model and explanation of the terms QoS and SLAs. The description of the optical fiber transmission follows after that. The characteristics of the waveguide and optical communication system components with regard to its reliable operation and management are analyzed. Some major types of optical networks are described. Following section contains a description of methods used in the audit, further the methods for measuring physical, connection and network layer of the reference model are discussed more thoroughly. The work also contains a partial analysis of the audit of the physical layer of the selected section of the Brno academic network optical line. Of all these methods for networks control the final audit report for the optical network with selected limits is compiled as a conclusion of the work.
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Effect of sub-micrometer structural features on rheology of polymer nanocomposites
Lepcio, Petr ; Chodák,, Ivan (referee) ; doc.Ing.Marián Lehocký, Ph.D. (referee) ; Jančář, Josef (advisor)
Polymerní nanokompozity (PNCs) mají slibnou budoucnost jako lehké funkční materiály zpracovatelné aditivními výrobními technologiemi. Jejich rychlému rozšíření však brání silná závislost jejich užitných vlastností na prostorovém uspořádání nanočástic (NP). Schopnost řídit disperzi nanočástic je tak klíčovým předpokladem pro jejich uplatnění ve funkčních kompozitech. Tato práce zkoumá přípravu polymerních nanokompozitů v modelové sklotvorné polymerní matrici roztokovou metodou, technikou schopnou vytvářet prostorové uspořádání nanočástic řízené strukturními a kinetickými parametry přípravného procesu. Prezentované výsledky popisují rozdíly mezi změnami rheologického chování roztoku polystyrenu při oscilačním smyku s vysokou amplitudou (LAOS) vyvolanými nanočásticemi. Výsledky vedou k závěru, že vysoce-afinní OP-POSS nanočástice při nízkých koncentracích dobře interagují s PS a tvoří tuhé agregáty, zatímco nízko-afinní OM-POSS nanočástice za těchto podmínek neovlivňují deformační chování polymerních řetězců. Dále byla pozornost zaměřena na vliv použitého rozpouštědla na uspořádání nanočástic v SiO2/PMMA a SiO2/PS nanokompozitech, který je v literatuře prezentován jako parametr řídící prostorové uspořádání nanočástic v pevném stavu. Důraz byl kladen na kvalitativní rozdíly mezi „špatně dispergovanými“ shluky nanočástic, které byly na základě rheologie a strukturální analýzy (TEM, USAXS) identifikovány jako polymerními řetězci vázané nanočásticové klastry a dva typy agregátů, jeden termodynamického a druhý kinetického původu. Jednotlivé druhy agregátů se vyznačují odlišnými kinetikami vzniku a rozdílnými vlastnostmi jak mezi sebou, tak v porovnání s dispergovanými nanočásticemi. Pozorované typy disperze nanočástic byly kvantitativně posouzeny podle svých rheologických vlastností během roztokové přípravy, podle kterých byla vyhodnocena míra adsorpce polymeru na povrch nanočástic a atrakce ve vypuzeném objemu. Výsledky byly porovnány s teorií PRISM. Důležitost uspořádání nanočástic byla demonstrována na porovnání teplot skelných přechodů různých struktur při stejném chemickém složení.
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Nonlinear phenomena in optical fibers
Burian, Radek ; Horváth, Tomáš (referee) ; Münster, Petr (advisor)
The subject of this thesis is to describe nonlinear phenomena in the optic fiber. The theoretical part describes a principle of transmission in optical fibers. Optics modules, fibers and their parameters are described marginally. Except nonlinear phenomena, there is also described linear phenomena such as attenuation, dispersion, scattering. In terms of nonlinear phenomena there is described second order phenomena such as Second harmonic generation (SHG), Sum and difference harmonic generation (SFG and DFG) and third order phenomena, such as Kerr effect, Third harmonic generation (THG), Four-wave mixing (FWM) and Cross phase modulation (XPM). There are also described nonlinear scattering, such as Raman´s and Brillouin´s scattering. The Four-wave mixing is simulated in the first half of the practical part. Four-wave mixing occurs in DWMD systems, where can invoke cross-talks between channels. In the second half of the practical part is measured this nonlinear phenomenon. The aim of the measurement is to understand the behaviour of the FWM and find the way how to eliminate its power. The Four-wave mixing measurement is based on the simulation. Second measurement is designed for Brillouin scattering. The conclusion from simulated and laboratory part from both measurements are compared with theoretical knowledge.
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Design of optical fiber sensor for vibration detection
Janoušek, Adam ; Münster, Petr (referee) ; Dejdar, Petr (advisor)
The master theses deals with a detailed analysis of optical fiber sensors. Specifically, there are discussed optical fibers, various types of sensors and realization optical fiber senzor and senzor system that has been optimized and processed data in real time. In master theses also describes the LabView programming enviroment and uses components, including the entire sensor systém of a sensors system that sends measured data
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