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Analysis of water demand depending on the level of temperature and precipitation
Malý, Vítězslav ; Slavíková, Lenka (advisor) ; Petŕužela, Lubomír (referee)
The demand for water is a very specific variable determined by many factors. The thesis aims to explain how does weather condition influenced the overall character of water demand. Predictions of climate change shows that in terms of CR it can expect changes in total precipitation during the seasons, the increase in average temperatures and a change in the variability and intensity of extreme events. The analysis therefore focuses on clarifying the impact of the level of temperature and precipitation on water withdrawals from public water supply. Analysis used daily data on the collection of water from public water supply for each interested location and daily hydrological data on the level of average daily air temperature and daily rainfall.
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Methods of calculating the spatial distribution of precipitation and differences in rainfall totals in a small catchment area
VÁVRA, Miroslav
This thesis is focused on methods of calculating the spatial distribution of precipitation and differences in rainfall totals in a small catchment area. The main aim is to find methods which enable transfer of spot measurements of precipitation to spatially distributed estimation and consequently comparison of results of these methods and evaluation of their differences and accuracy. For better understanding of this problematic, precipitation and its characteristics, origin and types are described. Factors which precipitation influence are also listed further in the text. The main part of this thesis is description of methods of spatial precipitation distribution and their application in a small catchment area. Methods are listed from the most common ones (Arithmetic mean method, Thiessen polygon method, Isohyetal method) to those most recent and least applied (Hypsometric method, Inverse distance weighted method, Kriging). Thiessen polygon method and Isohyetal method are described in detail and joined by figure for better understanding. Different methods of spatial precipitation distribution calculations (Thiessen polygon method, Isohyetal method, Arithmetic mean method) were compared on one catchment area with quite surprising results. The calculated values of rainfall totals in the catchment area differed only slightly using different calculation methods. It was also stated that not even with large number of rain gages in the catchment area we aren?t able to achieve 100% calculation accuracy.
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Floods in the South Bohemia Region
HRDÝ, Roman
Floods in the South Bohemia Region The first chapter provides general information including the current legislation of the Czech Republic pertinent to crisis management, floods, crisis situation and crisis state definition, and the categorisation of events/disasters, including flood. The important role of urbanism which affects the course and consequences of floods is also discussed. The second part deals with the issue of floods, their origin, classification, floodprotection measures and forecasting as connected with the Czech Hydrometeorological Institute whose functions and procedures are described. The main part presents results of the field survey carried out in the municipalities affected by floods in the South Bohemia. I describe, compare and analyze the last great floods in the years 1997, 2002 and 2006 in the Czech Republic, or the South Bohemia Region. Their intensity, progress, meteorological reasons and damages which they caused are evaluated. I generalize the factors with a direct influence on the extent of damages, including social and economic impact. In conclusion of this part, the danger of floods in the world is also mentioned. In the final part of my thesis, climatologists{\crq} opinions on global warming and the possible causation of this threat with floods are presented. The result is the confirmation or invalidation of the working hypothesis which I set for my thesis.
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Comparison of precipitation and runoff in the research area Jenin in relation to nitrates.
ŠULCOVÁ, Lucie
The influence of precipitation on runoff characteristics of tile drainage systems and nitrate concentrations in drainage water were evaluated in this thesis. The Jeninsky stream catchment is located at the foothill of Sumava Mountains near the border checkpoint Dolni Dvoriste. Extensive agriculture (pasture) is practised in the catchment as well as surrounding areas. Above mentioned evaluated characteristics were measured on two closure profiles of tile drained subcatchments. Discharges were measured continously, water quality was sampled forthnigtly. Evaluated hydrologic year 2007 was rich in rainfall {--} the precipitation amounted to 892 mm, which is classified as a wet year, despite of 41 days long dry period. Runoff characteristics don{\crq}t vary much in both subcatchments, due to similar area and land use on researched catchments. Long dry period did not cause zero discharges. The progress of nitrate concentrations in subcatchments is characterized by low variations in values. Relatively low values (90-percentil of nitrate concentrations in individual catchments belong to II. and III. class of water quality limits set by Czech legislative) occured in the catchment. These values correspond or slightly exceed values monitored on surrounding simirarly used areas, but are significantly lower than values monitored in areas, where intensive agriculture is practised. This confirms positive influence of grassing on nitrate pollution of drainage and surface water.
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Analýza výstupů klimatických modelů pomocí lineárních a nelineárních technik
Chládová, Zuzana
Regional climate models (RCMs) are currently one of regularly applied tools for localization of global climate models (GCMs) outcomes. This study is focused on analyses of mean daily temperature and precipitation using linear and nonlinear statistical techniques. 48 grid points of the regional climate models HIRHAM and RCAO and 29 meteorological stations of the Czech Republic were compared in the period 1961-1990. Mean annual courses of mean daily temperature and precipitation in the period 2071-2100 were analyzed at selected HIRHAM and RCAO grid points for A2 and B2 emission scenarios [IPCC, 2007]. Furthermore, time-delayed average mutual information (AMI) and autocorrelation function were analyzed. AMI and autocorrelation function were calculated for one selected time series of each grid point of the Czech Republic and Europe with a time lag varying from 1 to 10 days. The values of average mutual information were compared with values of autocorrelation function.
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Heat treatment conditions and their influence on precipitation of Ni4Ti3 phase in Ni-rich NiTi shape memory alloys
Dlouhý, Antonín ; Bojda, Ondřej ; Fiala, J.
The present work deals with a quantitative analysis of Ni4Ti3 precipitates after solution annealing (850°C/30min) and ageing (450°C/1hod) in air or inert argon atmosphere. The attention is given not only to the size of precipitates in the vicinity of grain boundaries and in the grain volume and to the corresponding Ni4Ti3 volume fractions, but also to subsequent martensitic transformations B2-(R)-B19’. Quantitative analysis of transmission electron microscopy micrographs is based on the automatic image processing by means of the Adaptive Contrast Control programme. Martensitic transformations were documented using differential scanning calorimetry. Results indicate a homogeneous precipitation of Ni4Ti3 with the heterogeneous distribution of crystallographic particle variants. A possible influence of the heat treatment environment on Ni4Ti3 precipitation and martensitic transformations is discussed in this work.
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Redistribuce napětí a její vliv na precipitaci v mikrostruktuře
Holec, David ; Dlouhý, Antonín
The present study considers two mechanisms that can contribute to the local redistribution of stresses in the microstructure of engineering alloys. The first model takes into account the anisotropy of thermal expansion coefficients and predicts a stress state generated close to a boundary between two differently oriented grains after a temperature change. The second model addresses a stress distribution in a polycrystalline aggregate characterized by anisotropic elastic constants and subjected to the isothermal aging under the assistance of external stress. The influence of local stress states on the selective precipitation of the Ni4Ti3 crystallographic variants in the microstructure of the NiTi shape memory alloy is demonstrated.
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Quantitative image analysis of precipitates in Ni-rich NiTi shape memory alloys
Bojda, Ondřej ; Dlouhý, Antonín ; Fiala, J.
A microstructure of a Ti-50.7at%Ni shape memory alloy resulting from solution annealing and subsequent aging at 500°C/3.6ks/8MPa is quantitatively analysed. The TEM study is assisted by Adaptive Contrast Control (ACC) routines embedded in a recent image processing system. The assessment focuses on the number density, size and distribution of crystallographic variants of Ni4Ti3 precipitates. It was found that the distribution of crystallographic particle variants in the microstructure is inhomogeneous. The influence of the heterogeneous Ni4Ti3 precipitation on the characteristics of the martensitic transformation B2®B19´ is briefly discussed.
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