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Analytical methods applied for the evaluation of environmental contamination by uranium ore mining
Bílek, Jiří ; Holubová, Zuzana (referee) ; Čáslavský, Josef (advisor)
This thesis deals with the testing procedures used in monitoring of environmental contamination after uranium ore mining in the uranium mine in Dolní Rožínka. It deals with the determination of radioactive elements radium, uranium and radon. The methods used for the determination of radioactive elements in mine laboratory in Dolní Rožínka are described. The thesis also mentions other applicable methods for determination of uranium. The metods of determination of manganese, iron and other metallic elements are also summarized in brief.The values of concentrations of monitored analytes in selected locations are presented at the end of the thesis. These values, which were provided by laboratories in Dolní Rožínka, are valid for 2010.
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Directional Image Representations
Zátyik, Ján ; Rajmic, Pavel (referee) ; Průša, Zdeněk (advisor)
Various methods describes an image by specific shapes, which are called basis or frames. With these basis can be transformed the image into a representation by transformation coefficients. The aim is that the image can be described by a small number of coefficients to obtain so-called sparse representation. This feature can be used for example for image compression. But basis are not able to describe all the shapes that may appear in the image. This lack increases the number of transformation coefficients describing the image. The aim of this thesis is to study the general principle of calculating the transformation coefficients and to compare classical methods of image analysis with some of the new methods of image analysis. Compares effectiveness of method for image reconstruction from a limited number of coefficients and a noisy image. Also, compares image interpolation method using characteristics of two different transformations with bicubic transformation. Theoretical part describes the transformation methods. Describes some methods from aspects of multi/resolution, localization in time and frequency domains, redundancy and directionality. Furthermore, gives examples of transformations on a particular image. The practical part of the thesis compares efficiency of the Fourier, Wavelet, Contourlet, Ridgelet, Radon, Wavelet Packet and WaveAtom transform in image recontruction from a limited number of the most significant transformation coefficients. Besides, ability of image denoising using these methods with thresholding techniques applied to transformation coefficients. The last section deals with the interpolation of image interpolation by combining of two methods and compares the results with the classical bicubic interpolation.
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The family house in Věžnice
Stránská, Miroslava ; Jelínek, Petr (referee) ; Hradil, Dušan (advisor)
Bachelor´s thesis deals with the project documentation for the realization of a new family house designed for inhabitition by four persons. The house has a partial basement and one floor. The construction is designed from traditional building materials. The house is roofed with a hipped roof. The thesis also contains a seminar thesis, which deals with waterproofing of lower part of the building and radon arrangement.
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Construction technological project of residential building in Liberec
Plachý, Jakub ; Hrdličková, Eliška (referee) ; Novotný, Michal (advisor)
This diploma thesis deal with phase of construction, which is foundation and upper construction of apartment building Komenského in Liberec. Building is situated in built-up and green area. Foundation circumstances is half difficult because of lower water included in soil. In this phase, we use formowork for columns, walls and roof. Used formwork is from Peri company, Quatro, Trio and Multiflex. There is suteren in the house, and because of lower water and high index of radon, we have to protect structure by compact waterproof isolation. This project contains formwork schematics and the time calculation needed to protect concrete until accomplishment. Other task is thermal review of constructions.
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Irradiation of the population from natural sources
UHLÍŘOVÁ, Daniela
Natural sources of radiation cause much higher exposure than artificial sources and can come in many forms. Natural sources of ionizing radiation are cosmic rays and natural radionuclides. Radon accounts for the largest percentage of the population's exposure. In the Czech Republic, radon occurs to a large extent, and because of this, we are among the countries with the largest volumetric activity of radon. The aim of the submitted bachelor's thesis was to find out and compare the awareness of the population in the area of natural sources of ionizing radiation in selected localities with high and low incidence of radon, namely Příbramsko and Mostecko. The theoretical part contains knowledge about radioactivity, biological effects of ionizing radiation, natural sources of ionizing radiation and quantities associated with ionizing radiation. A section is also devoted to the radon issue, health complications associated with radon and the radon program, which summarizes anti-radon measures. In the research part, the results of the questionnaire survey are summarized using graphs. These results are further processed using statistical methods, thanks to which both given hypotheses were confirmed. The first hypothesis examined whether the total awareness of the population would reach at least 70%, which was confirmed using a one-sample t-test. The second hypothesis related to the comparison of the knowledge of the population in the area of natural sources of ionizing radiation in people living in a locality with a higher incidence of radon and in people living in a locality with a lower incidence of radon, where the awareness of people in localities with a higher incidence of radon should be considerably higher. The hypothesis was confirmed using a two-sample t-test.
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Radon in a lake – an estimation of ground water input.
Porcal, Petr
A balance study of radon activity in Lake Plešný and its tributaries was carried out in 2020 to refine the estimate of groundwater resources. The balance is based on quantification of sources, monitoring of the amount of water draining from the lake, and lead concentrations in the overlying sediments.
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Public awareness about ionizing radiation from natural sources
HRBKOVÁ, Jana
Ionizing radiation comes from artificial or natural sources. Greater collective exposure of the population is caused by natural resources. Natural sources of ionizing radiation are cosmic radiation and natural radionuclides (cosmogenic and terrestrial). Radon and its products are the main contributors of natural irradiation. In the Czech Republic, the average indoor radon concentration is 118 Bq/m3, which ranks us among the countries with the highest average concentration of radon in dwellings. Radon is considered to be the second leading cause of lung cancer. Due to the possible health risks from radon, there is an effort in our country and in many other countries to regulate radon concentration in some way. The purpose of this diploma thesis was to find out how much is the public aware of the issue of ionizing radiation from natural sources and to create information material on this topic. Also compare how some countries approach the issue of radon regulation. In order to collect necessary data for my thesis a questionnaire survey was conducted. I also used professional resources. The electronic survey, which I created on website www.vyplnto.cz, was filled in by 362 respondents. All the results of the survey were displayed in pie charts. Questions no. 3-16, which were focused on awareness, were also displayed in bar charts, which show the percentage of correct answers by level of education. Thanks to the data from the survey I was able to answer research questions. In the first research question, I asked whether the public is sufficiently informed about ionizing radiation from natural sources; in the second research question, I wanted to know who has the least awareness on this topic based on education. I evaluated that the public is not sufficiently informed and people with just primary education have the least awareness about this topic. In the Canva program, I also created information material about ionizing radiation, in the form of a double-sided A5 leaflet. It can serve to increase public awareness of the issue. With help of professional sources, I also found out how some countries regulate radon concentration. I paid particular attention to the Czech Republic, where the history of radon regulation dates back to the 1990.
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Dating of radioactive mineral springs of the Krkonoše-Jizera crystalline by 230Th/234U method
Fanta, Martin ; Goliáš, Viktor (advisor) ; Mizera, Jiří (referee)
The isotopes 238 U, 234 U and 230 Th, as members of the uranium-radium decay chain, are fractionated in the environment by changes of geochemical conditions, and they can be used for dating of recent or past geochemical processes in the Quaternary. Samples of water with uranium and of water-activated solids were taken of radioactive mineral water springs at two study sites in the area of Krkonoše-Jizera crystalline complex: Svatý Vojtěch (St. Adalbert) in Horní Malá Úpa, and Bukový Pramen in the Těsný důl valley in Janské Lázně. Uranium was co-precipitated in field conditions with hydroxides of FeIII+ in 50-liter water samples of the radioactive springs. In the lab, uranium and thorium were separated from water precipitates, as well as from solid samples after their chemical decomposition, using chromatographic extraction agent UTEVA. All the three isotopes of interest emit alpha particles, and so their activities were measured by alpha spectrometry and expressed as 234 U/238 U and 230 Th/234 U ratios. As an internal standard, 232 U/228 Th was used. The resulting 234 U/238 U activity ratios of four water samples measured ranged from 1.0747 to 1.423. In twelve samples of solid phases activity ratios 234 U/238 U from 0.861 to 1.129 were determined. The 230 Th/234 U activity ratios form two distinct...
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Radioactive medicinal springs in the Skalná - Bad Brambach area
Turnová, Štěpánka ; Goliáš, Viktor (advisor) ; Vylita, Tomáš (referee)
Radiohydrochemical exploration took place in east part of the "smrčinský" pluton between "Skalná-Plesná-Bad Brambach in years 2016-2018. The main aim of the exploration was location and thorough research of possible occurrence of waters with radioactive concretation higher than 1500 Bq/l. That is a value for radioactive mineral waters given by the "lázeňským" law number 164/2001 Sb. Most important area is Plesná-south where was discovered several springs with values exceeding 5000 Bq/l. Eminent spring is called "Břetislav-Radonka" and lies one kilometre southwest from the train station Plesná-Šneky with an activity of about 12.5 kBq / l 222 Rn and a flow rate of about 2.5 l / min. It is the most active surface discharge of radon mineral water in the Czech Republic Another significant source area is north of Skalna - north. These springs were discovered almost 60 years ago, Dr. Marie Zukriegelová. The main source of this area was named after its discoverer - the "Marie Z" spring with an activity of 5800 Bq / l 222 Rn.Further the research focused on historical radioactive conduit which were used to supply village Skalné with water. The conduit was separated on two "branches" and the younger one was built ten years after the first one. In both pipes were found radioactive waters and the most important...
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Radon daughter products absorption by filters
Šálek, Ondřej ; Jáně, Zdeněk (advisor) ; Matolín, Milan (referee)
The work is engaged in effect of short-lived radon (222 Rn) daughter products on measurement of radon volume activity in soil gas. Solid radon daughter products 214 Po and 218 Po transform by α-decay and influence measurement of radon volume activity in soil gas. This effect was investigated by experimental measurement of radon volume activity in soil gas at the Buk radon reference site in Central Bohemia. At each particular point of radon reference site, three values of radon volume activity were determined by measuring; without filter, with automobile petrol filter and with micro-fibrous filter AFPC type. Experimental measurement demonstrates that both of applied filters have near the same effect on measured values of radon volume activity in soil gas. The difference between radon volume activity values got by measuring without filter and with filters is low, in order of measurement error. Experiment did not evidence necessity of using filter for measuring radon volume activity in soil gas. Radon volume activity measurement error is in order of several kBq.m-3 . This fact brings uncertainty into obtained results. The absence of theoretically possible high content of solid radon daughter products in soil gas samples may be explained by possible adsorption of these particles on sampling and soil...
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