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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.
271

Optimalizace provozu chloraminace v závislosti na kvalitě surové vody a nastavení provozních podmínek úpravny vody / Optimization of chloramination based on raw water quality and operational conditions of a water treatment plant

Švec, Pavel January 2009 (has links)
The most difficult part of water treatment is to ensure that water will be delivered to consumer in unchanged form and hygienic unexceptionable. To hygienic safety is using doses of chlor, whiches are deadly for organisms and inhibite their proliferation in pipeline. Modern way how to clear water from organism is called chloramination. By the help of ammonium salts chlor is released in sequence. So large single-shot doses of chlor aren´t necessary. Due the big dose was THM and another dangerous compounds formed.
272

Numerické řešení rovnic mělké vody / Numerical solution of the shallow water equations

Šerý, David January 2017 (has links)
The thesis deals with the numerical solution of partial differential equati- ons describing the flow of the so-called shallow water neglecting the flow in the vertical direction. These equations are of hyperbolical type of the first or- der with a reactive term representing the bottom topology. We discretize the resulting system of equations by the implicit space-time discontinuous Ga- lerkin method (STDGM). In the literature, the explicit techniques are used most of the time. The implicit approach is suitable especially for adaptive methods, because it allows the usage of different meshes for different time niveaus. In the thesis we derive the corresponding method and an adaptive algorithm. Finally, we present usage of the method in several examples. 1
273

Vliv organických látek produkovaných fytoplanktonem na charakter agregátů tvořených koagulací/flokulací při úpravě vody / The influence of algal organic matter on the character of aggregates formed during the coagulation/flocculation process in drinking water treatment

Filipenská, Monika January 2017 (has links)
Tato práce se zabývá studiem vlivu kaolinitových ástic (reprezentujících látky tvo ící zákal vody) a peptidové/proteinové složky COM (Cellular Organic Matter) produkovaných sinicí Microcystis aeruginosa na velikost, strukturu a tvar tvo ených agregát v prom nných hydrodynamických podmínkách (gradientu rychlosti) p i úprav vody. Agregace probíhala v Taylor-Couettov reaktoru. Koagulace vybraných typ zne iš ujících p ím sí (kaolinitové ástice, COM peptidy/proteiny a jejich sm s) probíhala pomocí síranu hlinitého a síranu železitého. Vzniklé agregáty byly hodnoceny ve fázi homogenní velikosti (steady state) po 60 min míchání pomocí ukazatel : velikost (polom r) agregát , fraktální dimenze D2 a Dpf a velikostní distribuce. Bylo zjišt no, že velikost agregát je závislá na typu koagula ního inidla, typu koagulované p ím si a aplikovaném gradientu rychlosti. S rostoucím gradientem rychlosti se velikost agregát zmenšuje. Železité koagula ní inidlo produkuje v tší agregáty než hlinité koagula ní inidlo. Podle p ím si roste velikost agregát v po adí kaolinit < COM < kaolinit + COM. Struktura agregát se stává kompaktn jší s gradientem rychlosti. P i použití hlinitého koagula ního inidla vznikají ve srovnání s inidlem železitým kompaktn jší agregáty (mají vyšší hodnotu D2). Kompaktnost agregát klesá v po adí...
274

Vliv podzemní drenáže a následné revitalizace na zásobu uhlíku a zadržování vody v povodí / The effect of artificial drainage and subsequent restoration on carbon stock and water retention in a watershed

Kešner, Michal January 2017 (has links)
In the 1980s, the meadows around Senotín in southern Bohemia were drained by subsurface pipe drainage. After considerable drought in 1992, this area was subjected to extensive research. In 1995, a part of the drained area was revitalized. The drainage pipeline was interrupted by seven clay screens, over four of them country lanes and shallow depressions were built. The research of this site was realized after revitalization and focused on the water regime of the soil and on the physical, chemical and biological properties of the soil. This thesis describes the state of water regime, physical and chemical parameters of soil in undrained, drained and revitalized areas 20 years after revitalization and compares them with data from research performed in the past. The rainfall and runoff data was measured in the catchment area, and soil samples were collected in the regular network. Research has shown that between 1998 and 2014 there has been a reduction in river runoff. However, a more detailed data analysis has identified the vegetation transpiration as the main factor. There has been no increase in soil retention or soil moisture. None of the investigated soil parameters on the revitalized area (bulk density, carbon and nitrogen content, C:N ratio, pH, and conductivity of the aqueous extract) is...
275

Ballast water management - current trends and economic impact of recently adopted regulations on the seafreight transportation market / Management balastní vody – aktuální vývoj a ekonomický vliv přijímaných opatření na trh námořní přepravy

Pavlíčková, Veronika January 2015 (has links)
This master thesis deals with the very current topic of ballast water management, a very specific field in the maritime shipping industry. The aim of the thesis is to introduce the subject clearly and to sum up the main issues which restrain a smooth implementation of new regulations that emerged from a recently adopted international treaty. This treaty, the so-called Ballast Water Management Convention, will possibly have immediate impact on the seafreight market rates and thus on the entire international trade. So purpose of this thesis is to estimate what the result might be like.
276

Výzvy pre republiku Jemen v 21.storočí / Challenges for the Republic of Yemen in the 21st century.

Sadovenková, Ľubica January 2011 (has links)
The thesis aims to take a closer look at fundamental problematic areas of Yemeni society, carries out their deeper analysis and identifies the root causes. It deals specifically with human capital from quantitative(demographic trends) as well as qualitative perspective (level of human development) and analyses current political and security situation. The thesis focuses also on the natural resources -- water and oil, their depletion and estimated available amounts. Yemen will likely become the first country ever to run out of underground water resources. A combination of natural dispositions, economy orientation and technology level could possibly lead to the first humanitarian disaster of its kind. In terms of oil production, Yemen is a small exporter on the global level, however the public finance together with public services provision are on the sector highly depended.
277

Řízení vírového proudění v sací troubě vodní turbíny / Flow control in a hydraulic turbine draft tube

Litera, Jiří January 2017 (has links)
Hydraulic energy is one of the most important sources in the world for electricity production. Nowadays the trend is to limit the production of the electricity from fossil fuels and to protect the environment. The main idea is to use more renewable energy sources such as wind and solar energy. Unfortunately, these alternative sources are strongly dependent on current weather conditions, which causes the instability of the electrical grid. Luckily pumped storage and hydraulic power plants provide the solution. However, it requires an extension of the operating range of the hydraulic machines. For that reason, the water turbines now operate over and extended range of regimes, that can be quite far from the best efficiency point. Hence two types of unstable two-phase flows in the Francis turbine draft tube occur: part load overload. This diploma’s thesis is focused on the Francis turbine operating at the part load. During part load conditions the helical vortex rope is being developed in the draft tube, it causes pressure pulsation and it can lead to the hydro-acoustic resonance, which damages the elements of the power plant. The aim is to eliminate the pulsation by jet control of the swirling flow in the draft tube. In the diploma’s thesis, various approaches to jet control of the flow in conical diffuser are tested using the computational fluid dynamics.
278

Analýza spotřeby vody v areálu FAST VUT Brno / Analysis of Water Consupmtion in Campus of FAST VUT Brno

Fogl, Jiří January 2018 (has links)
The subject of the diploma thesis is the analysis of water consumption in the area of the Faculty of Civil Engineering, Brno University of Technology. The main part of the thesis deals with the analysis of the measured data, which are recorded using a data logger located on the VF2 billing water meter. The processing of consumption curves is focused on individual working days, for days with or without instruction. From the results of the individual analyzes, maximum hourly limits are set for signaling of undesirable sampling states. In the end, the Smart Water Meters principle is introduced in the Czech Republic and abroad and a technical solution for the replacement of all billing water meters in the FAST area with new smart meters has been made.
279

Energetický posudek solární soustavy / Energy Assessment of Solar System

Šmardová, Eva January 2018 (has links)
The first part of diploma thesis describes how to measure the parameters of solar thermal collector and solar thermal system. The computational part analyzes heat consumption in the evaluated building and describes design of the solar thermal system for domestic hot water. Last part focuses on the energy assessment of the designed solar system above and evaluation of the solar system, which is located at the Faculty of Civil Engineering in BUT.
280

Cena vody ve vybraných obcích České republiky / The price of water in selected municipalities of the Czech Republic

Vázlerová, Marcela January 2019 (has links)
The diploma thesis deals with the problems related to operation of water supply and sewerage systems in the Czech Republic. The view is focused on the calculation of the water price for the customer because of large scope of the topic. The diploma thesis also describes the technical development of water management infrastructure, ways of operation of water supply and sewerage systems and the development of water and sewer rate price. The main aim of the thesis is to describe the specific situation in the selected village and the voluntary association of municipalities. It is focused to calculating water and sewer rate price. For a good overview in the prices of water and sewer rate in the Czech Republic, the prices in the selected municipality and the voluntary association of municipalities are compared with prices in the Czech Republic, in general.

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