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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.
321

"Všechno je lehounké a vše je nahoře a nejvýše je tanec slonů". Metafory pohybu v díle Vladimíra Holana. / "Everything's light and everything's upwards, the dance of elephants being uppermost". The metaphors of the movement in poetry of the poet Vladimir Holan.

Hudcová, Zuzana January 2011 (has links)
The purpose of the thesis is to deal with a writings of Vladimir Holan as a thematic unity, where the motifs are transformed. The metamorphosis depend on a time, when they have been written in. Our used method of his writings is in a chronological order. This thesis is focused on the motif of a movement and his metamorphosis in poetry of Vladimir Holan. The aim is to penetrate the problems of the movement as a physical activity and approached the movement as a confirmation of existence on a basis of Patočka's phenomenological phylosophy. Other chapters pay attention to analysis of motifs of movement, which are recognizable in Holan's poetry. Their feature change from lightness and freedom to heaviness and limitation. Afterwards the point of this work reaches the axis: a wind - a wave - a water flowed - a bird - a cloud - a stone - a snake - a wall. Due to the better understanding of Holan's work, we make a passing comment about the motifs which are connected with notised above. These connections will able to put our thoughts about Holan's conception in order.
322

Interakce podzemní a povrchové vody za extrémních hydrologických situací v nivě horní Lužnice / Interaction of groundwater and surface water under extreme hydrological conditions in the floodplain of the upper Lužnice river

Fialová, Petra January 2015 (has links)
The object of this work is an analysis of the influence of extreme hydrological events (floods and droughts) in terms of interaction between groundwater and surface water in the river floodplain. The aim of this thesis is also the evaluation of the hydrological regime of the upper Lužnice basin and evidence of retention potential preserved natural floodplain. The selected objectives of the work were resolved on the basis of the values of groundwater levels and surface water in the area of interest. Based on data from underground wells and a digital terrain model, it was possible to create an image of the distribution of groundwater levels in river floodplains during selected hydrological situations. Data from surface flow was obtained from several habitats in the flow direction Lužnice. This has enabled graphically illustrate individual flood waves and characterize their size, speed and transformation after the passage of a preserved natural floodplain of Lužnice river. Carried out research has been confirmed retention capacity of the floodplain, which is most significant at flow rates slightly in excess of the flow capacity of the river bed. However, extreme floods or in periods with many culminations in a relatively short time leads to reduces water retention capability of the floodplain. In...
323

Matematický model proudění podzemní vody v oblasti s cirkulačním vrtem / Mathematical model of groundwater flow during operation of a circulation well

Žáková, Tereza January 2014 (has links)
In this master's thesis, a numerical model of groundwater flow in a contaminated area of Hradec Králové was created. After that, a circulation well was introduced. Two circulation well variants, which differ in the amount of pumped water, were examined. All simulations were performed with the aid of a finite element solver Feflow 5.2. The values of hydraulic head resulting from the mathematical model are in a good agreement with those obtained from the field measurement. The groundwater flow present in the area of interest exhibits south to southwest direction. After introducing the circulation well, I focused on the influence of the amount of pumped water on the groundwater flow. The outcome of this observation was that during the higher volume pumping, the circulation cell is larger and therefore has a higher influence on the groundwater flow. I evaluated that it is more efficient to pump a higher amount of water in the investigated area.
324

Schémata typu ADER pro řešení rovnic mělké vody / ADER schemes for the shallow water equations

Monhartová, Petra January 2013 (has links)
In the present work we study the numerical solution of shallow water equations. We introduce a vectorial notation of equations laws of conservation from which we derive the shallow water equations (SWE). There is the simplify its derivation, notation and the most important features. The original contribution is to derive equations for shallow water without the using of Leibniz's formula. There we report the finite volume method with the numerical flow of Vijayasundaram type for SWE. We present a description of the linear reconstruction, quadratic reconstruction and ENO reconstruction and their using for increasing of order accuracy. We demonstrate using of linear reconstruction in finite volume method of second order accuracy. This method is programmed in Octave language and used for solving of two problems. We apply the method of the ADER type for the shallow water equations. This method was originally designed for the Euler's equation.
325

Ekologické hodnocení toků v CHKO Křivoklátsko v rámci Směrnice 2000/60/ES / Ecological evaluation of streams in protected area Křivoklátsko in Directive 2000/60/ES

Kesnerová, Lucie January 2013 (has links)
This thesis deals with the monitoring of water quality and aquatic sediments analysis in the protected area Křivoklátsko. Monitoring was carried out at 16 locations and there were determined 14 physico-chemical parameters . Sediment samples were collected once for the whole period at 14 locations in which was determine the content of metals. In each sediment sample there was analyzed content of selected metals. The results of analysis, water and sediment samples were evaluated according to the Directives and regulations giving limits for water and sediment. Due to the Czech Republic is a member state of the European Union, the state was also evaluated according to Water Framework Directive. Theoretical part of thesis decribes characteristics of metals, their forms in water and soils. This section also contain some informations about water framework directive 2000/60/EC as a great step in a water policy. Moreover there is a short history about development water quality in the Czech Republic. Experimental section contains standards for determining water quality, but indicating in particular the processing of sediment samples from sampling to determine concentrations. The following chapter deals with the evaluation of the results given by legislation - for water to the CSN 75 7221 and Regulation...
326

Hodnocení zátěže životního prostředí v ČR pomocí indikátoru Vodní stopa / Environmental assessment of the Czech Republic based on Water Footprint

Žlábková, Jana January 2013 (has links)
This dissertation sets its goal in application of the water footprint indicator, which is a practical and multi-layered indicator of water sources consumption. Of human activities, agriculture presents the most significant demands on water sources consumption. Therefore I have turned my focus to the widely-discussed issue of biofuels production, because the input materials for production of this kind of energy are agricultural crops (in the Czech republic those are: oilseed rape, sugar beet, Indian corn and winter wheat). The calculated results of water footprints of the selected industrial crops (m3 /t) and of water footprints of the heating value units of that crops (m3 /GJ) offer us a concrete notion of energy requirements of water of that chosen industrial crops in the conditions of the Czech republic. Keywords: water footprint indicator, biofuels, oilseed rape, water consumption, biodiesel, bioethanol, evapotranspiration.
327

Nukleace kyseliny sírové a vody - laboratorní a atmosférická pozorování / Nucleation of Sulphuric Acid and Water - Laboratory and Atmospheric Observations

Škrabalová, Lenka January 2016 (has links)
1 ABSTRACT: This study is dedicated to the study of nucleation of sulphuric acid and water, which presents the key process associated with secondary aerosol formation via gas to particle conversion. We investigated the nucleation rates, new aerosol particles formation and growth dynamics of newly nucleated particles. These processes were explored in both laboratory and field experiments. In the laboratory measurements, we explored the H2SO4 - H2O nucleation rates and growth rates of newly formed particles under well-defined conditions and we also investigated the effect of experimental conditions on particle growth dynamics. Furthermore, we proposed a model, which predicts the particle growth and accounts for condensation of H2SO4, H2O and NH3. The comparison of experimental growth rates with atmospheric ones was made and resulting implications of the chemical nature of compounds involved in the early growth of nucleated particles is also presented. To investigate the atmospheric H2SO4 - H2O nucleation and new particle formation, we analysed a two-year long dataset of particle number size distributions, obtained from a urban background station in Prague Suchdol. A special attention was given to a recently reported special feature of particle growth dynamics - a particle shrinkage following previous new...
328

Tvorba a estimace modelu malé vodní elektrárny v programu PSCAD / Creation and estimation of small hydro power plant model in PSCAD

Razyapova, Aygul Unknown Date (has links)
This thesis focused on creating a model of a small hydropower plant model (SHPP) and a part of the electricity network in the simulation software "PSCAD" (basing on real sources). The model will be specified on the basis of the data obtained from the measurements to correspond with the real equipment.
329

Analýza srážko-odtokových procesů a erozních charakteristik vybraného povodí při různém uspořádání krajiny

VANČUROVÁ, Lenka January 2019 (has links)
The diploma thesis focuses on the analysis of rainfall-runoff processes and erosion characteristics of selected catchment in different landscape management. This analysis was solved at the Lukavecký brook catchment, which is located in the Pelhřimov district in Vysočina region. The theoretical part of the thesis describes the rainfall-runoff process and then focuses more on individual processes. It also characterizes water erosion, its consequences, forms and erosion control. At the end of the theoretical part are described methods of calculation of water runoff and water erosion. The practical part describes the catchment of the Lukavecký brook, its characteristics of natural conditions and the threat of water erosion. Then there is a procedure for processing of bases and data in the program ArcGIS. Subsequently, it includes an assessment of the different measures and changes in the type of land to drain water from the catchment and erosion threat.
330

Adsorpce nízkomolekulární složky organických látek produkovaných fytoplanktonem na aktivním uhlí při úpravě vody / Adsorption of low molecular weight algal organic matter onto activated carbon during water treatment

Fialová, Kateřina January 2019 (has links)
This diploma thesis deals with the study of adsorption of low-molecular components of organic substances produced by phytoplankton - AOM (Algal Organic Matter) on AC (Activated Carbon) during drinking water treatment. For the experimental purpose in this thesis, there were used selected amino acids as low molecular substances of AOM that are difficult to remove by conventional water treatment process by coagulation. As adsorbent, there was used a detailed characterized of granulated activated carbon (GAC) - Filtrasorb TL 830 (FTL830) which is intended directly for the purpose of water treatment. There were realizing the equilibrium batch adsorption experiments with three different model amino acids - arginine (Arg), phenylalanine (Phe) and aspartic acid (Asp). There was investigated the efficiency of removing amino acid depending on the solution temperature and pH. Results of the adsorption experiments have shown that the temperature affects the adsorption efficiency. Adsorption is essentially described as an exothermic process but the adsorption of Arg and Phe from an aqueous solution to GAC occurs more efficiently at higher temperatures. It means that the adsorption is the endothermic process. In the case of Arg adsorption, the temperature was found to influence adsorption efficiency less than...

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