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  • About
  • The Global ETD Search service is a free service for researchers to find electronic theses and dissertations. This service is provided by the Networked Digital Library of Theses and Dissertations.
    Our metadata is collected from universities around the world. If you manage a university/consortium/country archive and want to be added, details can be found on the NDLTD website.
81

Návrh výplňových prvků s trabekulární strukturou pro revizní implantát kolenního kloubu / Design of filling elements with trabecular structure for revision implant of total knee arthroplasty

Lang, Roman January 2014 (has links)
This diploma thesis describes the design of filling element with trabecular structure for revision implant of total knee arthroplasty. Design of the filling element is created by the digital data of the patient tissue. Production of a functional sample is performed using additive technology Selective Laser Melting. This work also include analyze of the accuracy of this technology for the production of titanium alloy Ti6Al4V.
82

Vliv anorganických plniv na elektrické vlastnosti epoxidových pryskyřic / Inorganic fillers effect on electrical properties of the epoxy resins

Doležel, Tomáš January 2016 (has links)
This thesis deals with problems of electrical insulation materials based on epoxy composites used in the electronics industry. This thesis is divided into theoretical part focused on composite materials, their technological processing and diagnostics. It also describes dielectric materials, their properties and events taking place in their structure. The experimental section describes the measurement of electrical properties of samples of electrical insulating materials with different types of fillers.
83

Vývoj meziplanetárních koronárních výronů hmoty / Evolution of interplanetary coronal mass ejections

Lynnyk, Andrii January 2011 (has links)
Title: Evolution of Interplanetary Coronal Mass Ejections Author: Andrii Lynnyk Department: Department of Surface and Plasma Science Supervisor: RNDr. Marek Vandas, DrSc. e-mail address: vandas@ig.cas.cz Abstract: This thesis deals with deformation of the Interplanetary Coronal Mass Ejections (ICMEs) and their sub-class Magnetic Clouds (MCs) during their propagation in the Solar Wind (SW). The statistical study of the expanded MCs has shown that expansion greatly affects the MC internal magnetic field. We had shown that this influence is more clear for the MCs observed close to their axes. The study of the stand-off shock distance in front of the supersonic ICME confirms a smooth deformation of the ICMEs along their path from the Sun into interplanetary space. We observed that this deformation is increasing with the velocity of the ICME. This study also confirmed the difference in sheaths that are created in front of expanding and non-expanding ICMEs. We found that velocity distribution inside the MC is not uniform and it has large fluctuations. We found that the MC cross-section is usually strongly deformed. Keywords: interplanetary coronal mass ejection, magnetic cloud, magnetosheath, flux rope, magnetic field, shock, fitting
84

Určování základních vlastností hvězd skrze analýzu vhodných dvojhvězd a vícenásoných systémů / Determination of accurate fundamental stellar properties of stars via analyses of suitable binary and multiple systems

Nemravová, Jana Alexandra January 2016 (has links)
Context: Binaries and multiple systems are very frequent and form large fraction of all stellar systems. In contrast to their single counterparts, studying binaries provides the possibility to accurately determine fundamental properties of their components that are needed for testing models of stellar structure and evolution. On top of that, binaries can be used for accurate distance determinations. The mass exchange in close binaries remains the only mechanism, which completely alters their evolution. Aims: The primary goal of my doctoral study was to determine orbital elements of selected systems and properties of their components - masses, radii, and ef- fective temperatures. - In case of more complicated objects (e.g. interacting multiple systems, mass-transferring binaries, . . . ) the secondary goal was to confront our results with predictions of theoretical models. Methods: Studies that I co-authored were based on three different types of ob- servations, each sensitive to partly different properties of studied systems - photometry, spectroscopy, and spectro-interferometry. The analysis was carried out through several "observation-specific" models, whose outcome was critically compared to each other and to previous studies of the object in question. Results: Throughout my study I contributed to: (i)...
85

Kostní remodelace u revmatických onemocnění: Ztráta kosti u pacientů s juvenilní idiopatickou artritidou. / Bone remodeling in rheumatic diseases: Bone loss in juvenile idiopathic arthritis

Brábníková Marešová, Kristýna January 2015 (has links)
Introduction: The inflammation plays the essential role in the bone loss in juvenile idiopathic arthritis (JIA). Proinflammatory cytokines and also glucocorticoids (GCs) may activate bone resorption by osteoclasts. Simultaneously, bone formation can be attenuated, especially by inhibitors of proteins, which control the osteoblast differentiation. The aim was to verify the hypothesis that in patients with highly active JIA, reduction of bone formation via Wingless (Wnt) proteins inhibitors - Dickkopf 1 (Dkk-1) and sclerostin could be found. Except the densitometry measurements of bone and lean mass, we assessed markers of disease activity, bone metabolism and remodeling in young adult patients with JIA before and during 2 years of anti TNFα (tumour necrosis factor α) treatment, which decreases disease activity. Results: In patients with JIA before antiTNFα treatment, bone mineral density (BMD, g/cmš) was significantly reduced compared to controls. Values of BMD and body composition in JIA significantly depended on disease duration and GCs treatment. Serum concentration of sclerostin was significantly elevated in JIA compared to values in healthy controls. Values of the other monitored markers did not differ between JIA and controls. In patients with JIA, Dkk-1 correlated positively with C-reactive...
86

Vliv ztráty hmoty hvězd na dynamiku hvězdokup / The influence of the stellar mass-loss on the dynamics of star clusters

Dinnbier, František January 2012 (has links)
This work aims at studying the influence of the stellar mass-loss, resulting from the stellar evolution, on the dynamics of massive star clusters. The emphasis has been put on the mass-loss by low-mass and intermediate-mass stars (m < 8 Mo) that form, at the end of their life, a planetary nebula. The expansion speed of gas released by these stars is lower than the escape speed from sufficiently massive star clusters, and the gas can be retained by the cluster. For modelling of the gas hydrodynamics, a simple sticky-particles method was used. To carry out simulations in which gaseous and stellar particles mutually interact through their gravity, substantial modifications had to be realized in the N-body codes Nbody6 and Hermit. For the sake of comparing the influence of stellar mass-loss and relaxation processes, which are happening in the simplified model, two types of simulations were performed: one with the formation of gaseous particles and the other consisting of purely stellar component. The simulations in which the gas component was present showed out a significantly different evolution in the central part of the cluster than those in which the presence of gas was not considered.
87

Stabilní izotopy uhlíku v letokruzích smrku jako marker napadení stromu patogenní houbou. / Carbon Stable Isotopes in Spruce Tree Rings as a Marker of Pathogenic Fungal Attack of Trees.

NECUDOVÁ, Lucie January 2013 (has links)
Trees are long living plants, which use carbon from the air and hydrogen and oxygen predominantly from soil water for their growth. They deposit these elements largely into a wood where they may persist for thousands of years. Tree growth is influenced by environment, especially by air temperature and precipitation. These factors have an effect on stomatal conductance and photosynthesis rate which influence carbon stable isotope ratio (13C/12C) in the tree tissue. This thesis is focus on stable carbon isotopes in tree-rings of Norway spruce attacked by honey mushroom, and Norway spruce which doesn?t show any signs of disease. The hypothesis of the thesis is based on an expected difference in carbon isotope fractionation during photosynthesis between the spruce attacked by honey mushroom and a ?healthy? spruce. The difference in isotope fractionation could be caused by water deficit induced by honey mushroom disease in the tree. We expect that the attacked spruce defends against water loss by closing stomata, and it could lead to lower CO2 concentration in the needles and higher ?13C value in tree-rings biomass The stable carbon isotope analysis (IRMS) was done on tree-rings of four spruce pairs, each one including an attacked spruce and spruce which didn?t show any signs of disease. Carbon isotope ratio of early wood, late wood and in biomass of the whole annual increment was measured. In contrary to our hypothesis we did not fined any systematic difference in isotopic composition between the attacked spruce and the spruce which did not show any signs of disease.
88

Zjištění, vyčíslení a rozbor nákladů na výrobu senáže ve vybraném podniku s vyšší svaživostí pozemků. / Location, evalution and analysis of the cost for production of a pasturage in chosen establishment with higher steep lands.

KÜMMEL, Miloš January 2009 (has links)
The graduated thesis is described the characteristic of a permanent grass vegetations, analysis of the scale of production a pasturage in chosen establishment and identification with a technological line for harvest and conservation pasturage. Next describe size of a store, land steep a traffic distance. This thesis describes measuring procedure in order to location of engineering characteristics, consumption of fuels and financial evaluation of all operation in the end.
89

Možnosti zužitkování travní hmoty. / Possible utilization of grass material

KOBERNA, Daniel January 2008 (has links)
The objective if this degree work is creating a survey of possible uses of surplus grass material which is caused by animal farming reduction and by bringing the ground in less fertile areas of our country to a standstill. In the work possible uses of the grass are described, especially its use in the energy industry as a fuel source for the production of heat and biogas. Classical usage of the grass material as a food source for livestock or for the production of compost is described here as well. Examples are shown there of energy kinds of grass, which seems to be a promising renewable resource of biomass for favourable economic results. The harvest of the grass material and its consequent prossesing is done by production lines, that is why a survey of such lines and their economic figures connected with the operation of these machines is also included in this work. The economic part of this work contains many formulae that can be used for counting out all the costs connected with the operation of the grass harvest machine and for evaluating the effectiveness of the return on investment into this machine
90

ELECTROCHEMICAL DETECTOR WITH ELECTRODES ARRAY AND ROTATING DISK / ELECTROCHEMICAL DETECTOR WITH ELECTRODES ARRAY AND ROTATING DISK

SAJDLOVÁ, Zuzana January 2010 (has links)
The thesis deals with the testing and optimization of hydrodynamic conditions of the electrochemical detector, which consists of a flow cell containing the electrochemical sensor with an array of electrodes. The flow cell includes a rotating disc-shaped component, which allows radial flow of analytes along the sensor electrodes. This principle imitates the rotating disk electrode, with the difference that here the electrodes are immobile. Hydrodynamic phenomena in this case are similar to RDE. Therefore, the theoretical part of my work deals with hydrodynamics and mass transfer for the well-described case of rotating disk electrode. It was found that in the current set-up under certain conditions, an analyte flowed back from the output cell channel to the sensor, even at the laminar flow. This causes a nonlinear response of the electrodes and their low reproducibility. The solution is to reduce the distance between the rotation component and the electrodes surface and reduce flow speed of analyzed liquid towards the sensor. A novel type of sensor with annular electrodes was designed and tested. It showed four times higher conversion rate of the analyte compared with the originally used AC9 electrochemical sensor having electrodes in the form of full circles lying on a circumference of a common circle. Based on calculations, conversion of the analyte on the plane electrode can be increased up to 100% when using this annular sensor, adjusting flow cell and reducing of the input flow rate. The detector was connected to the liquid chromatograph and its function was tested on two substances - ascorbic acid and dopamine. For the current detector these parameters were set: dynamic range, linearity, noise, detection limit, time constant and the temperature range at which the detector can be operated.

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