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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.
11

Povrchové zpracování vybraných ocelí pomocí elektronového svazku / Surface treatment of selected steels using electron beam

Matlák, Jiří January 2013 (has links)
The aim of diploma thesis was preparation of hardened layer on three chosen types of materials with different alloying components content without surface melt by using electron beam technology. The influence of chosen process parameters was observed on the prepared hardened layers properties and shapes. In the first part of bibliographic search there are described electron beam properties, possibilities of his influencing and control. There is given example of complete set of electron beam are mentioned in the second part of theoretical research.
12

Morfologie dvoukomponentních povrchových struktur / Morphology of two-component surface structures

Babjak, Viktor January 2010 (has links)
In the presented thesis we investigate heteroepitaxial growth of one element (one type of adsorbate A with negative or positive misfit relative to substrate S) and static properties of two-component surface alloy, i.e. ternary system (two types of adsorbate A and B with negative and positive misfit relative to different substrat S). We use Monte Carlo simulations for an off-lattice model in (1+1) dimensions with Lennard-Jones interaction. In case of incoherent heteroepitaxial growth we investigate formation of misfit dislocations, their influence on structure of growing film and impurity-induced formation of dislocations. Two different types of formation of dislocations are found, depending on the sign and magnitude of misfit. Simulations of static properties of two-component surface alloys show that morphology is quite different for phase separation (formation of domains consist of one type of particles in direction along and vertically towards to substrate-adsorbate interface) and intermixing regime. The structures, which emerged, depend on relative misfit, interaction and concentration of individual elements.
13

Změny hlubokého a povrchového čití u depresivní poruchy / Changes in deep and superficial sensations in depression

Janoušková, Marie January 2013 (has links)
Title: Changes in deep and superficial sensations in depression Objectives: The theoretical part of this study aims to summarize the issues related to depression and sensory modalities in general. The goal of the practical aspect is to conduct an experiment that evaluates changes in superficial and deep sensations in depression at different stages of the mental illness in five patients. We evaluated sensations of thermal stimuli, tactile stimuli, vibrations and pain. Methods: The practical part describes the sensation analysis for each patient individually. The changes in deep and superficial sensations are compared in states of worse and lighter depression. There is also a suggested possibility for statistical evaluation of the interdependence between the severity of depression and selected modalities of sensation using the Wilcoxon test for two dependent samples. Results: The vibrating sensation in the upper left limb and algid sensation in the upper right extremity proved (on the chosen level of significance) the null hypothesis which stated that changes in sensation depend on changes in the state of depression. A sense of vibration in the upper right extremity, a sense of pain in the upper left limb and other sensory modalities present in both upper extremities were accepted (on the chosen...
14

Vliv chemických zdrojů znečištění na jakost povrchových vod v povodí Horní Vltavy

NEKOLNÝ, Tomáš January 2019 (has links)
The diploma thesis is focused on the issue of surface water pollution, which is one of the biggest problems of the contemporary world. The pollution of watercourses and reservoirs worsens the quality of aquatic ecosystems as well as ecosystems in their surroundings. The typical sources of surface water pollution include especially point sources (human settlements, industrial sites) and land resources (agriculture). While the point sources of pollution can be monitored, the situation is far more complicated for the field sources. In agricultural farming, the fertilizer residues, pesticides and other substances come into the groundwater and the surface water. The aim of this work is to find out the quality of surface water in the measuring profiles (river Malše), to find out the hydrological situation during the year and to evaluate the impact of chemical pollution sources influencing the quality of the surface water in the river basin.
15

Analýza rychlosti šíření trhliny pro vybraná zemětřesení z regionálních záznamů povrchových vln / Analysis of rupture velocity for selected earthquakes utilizing regional recordings of surface waves

Čejka, František January 2018 (has links)
Supershear earthquake is an interesting phenomena that is still without a robust method for its proving. In 2012 Vallée and Dunham (2012) published a method that studied far-field waveforms from supershear earthquakes. They conclude that unilateral supershear ruptures have similar shape of surface waves on the border of Mach cone as surface waves of smaller earthquake with the similar mechanism and location. In this work we use their method and we developed a script in Python with use of ObsPy library. Our script is capable of downloading and processing data from worldwide seismic databases like IRIS. We tested our program on a supershear earthquake in 2001, Kokoxili, China, which was studied in the original paper. Our results were the same as the original one. Then we use our script to other potential supershear earthquakes: Denali 2002, Yushu 2010 and Aegean sea 2014 to test the method and its results. We conclude that this method is relatively stable for large earthquakes like Kokoxili where we have a big difference between the main shock and the small one. For smaller events there could be a problem with seismic noise and proper setting of frequention.
16

Vliv teploty a vlhkosti na kvalitu povrchové úpravy nábytkových dílců

Jergl, Zdeněk January 2007 (has links)
No description available.
17

Vliv technologie, kompozitních materiálů a povrchové úpravy na emise VOC emitované nábytkem

Čech, Petr January 2008 (has links)
No description available.
18

Gliding Arc / Gliding Arc

KALA, Jaroslav January 2012 (has links)
The thesis is focused on increasing the surface tension of polyethylen, using plasma. A gliding arc was chosen for this surface modi cation. The theoretical part includes an overview of gas discharges, their classi cation, properties and technical applications, and deals with an in uence of surface tension on surface modi cations of materials. The experiment is explained in the practical part, a jet analysis carried out before the experiment is described. Results of the experiment are presented.
19

Analýza časových řad koncentrací aniontů a kationtů na povodí Kopaninského toku ve vazbě na využití půdy. / Analysis of time series of anions and cations concentrations in the Kopaninsky stream catchment in relation to land use.

KOUŘIMSKÁ, Kateřina January 2008 (has links)
Water quality of small streams in agricultural landscape is mostly classified as polluted or very polluted. The reason of enhanced mineralization of organic mass in soil can be found in changed physical, chemical and biochemical properties of soil profile, which negatively display in mineralization of organic mass and nitrogen release to soil water. Analysis of water quality in agricultural river-basin prove that quality of surface water in areas with high nitrate loadings did not significantly improve in recent years. Nitrates in water are a distinct anthropogenic factor, which defines well disturbance in natural environment. This thesis deals with analysis of time series of nitrate concentrations in the Kopaninsky stream catchment in Bohemo-Moravian Highland. Further the progress in nitrate concentration and its seasonal component is researched.
20

Měření povrchového napětí kapalin / Surface tension measurements

Hála, Ondřej January 2017 (has links)
The thesis deals with study of surface tension of liquids and measuring possibilities of this parameter. The paper is then focused on design of measuring apparatus based on pendant drop method. The apparatus is controlled with software written in Matlab. Several measurements are done at the end of this work, which confirm possibility to practical use of this apparatus for surface tension measurements. A part of this work is manual to use the apparatus and complete design documentation.

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