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Verification of the model for predicting the properties of the combustion process
Horsák, Jan ; Kilkovský, Bohuslav (referee) ; Jegla, Zdeněk (advisor)
This work thoroughly analyzes a previously created computational model for predicting characteristic properties of the combustion process in an experimental combustion chamber. Any found shortcomings of the original model are removed and the model is further improved prior to its application on 11 real cases of combustion tests performed at various conditions and with various fuels. Data provided by the model are confronted with the data obtained during the combustion tests and the model accuracy is evaluated, based on local heat flux along the length of the combustion chamber. Finally, the overall usefulness of the model is determined by the means of evaluating the acquired accuracy values, and further possibilities of model improvement and use are presented.
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Engineering solution of photovoltaic power station
Gajdošík, Ivo ; Sobotka, Jiří (referee) ; Míča, Ivan (advisor)
This thesis deals with the usage of solar photovoltaic panel production of electic energy. First part focuses on solar radiation alighting the Earth, respectively the area of Czech republic. Next part covers a development of photovoltaic from the very beggining til nowadays, it describes its spread in the world and the area of Czech republic. Then a reader us introduced to physical principles that work inside solar cells a one single chapter desribes individual parts of photovoltaic power station. Next chapter is dedicated to a model study of photovoltaic power station devided in two alternates- with stacionary placement of panel and placement on trackers, where after a market research, there is a whole technical solution designed and economical and delivery balance is calculated. At the last part there are described main directions of development in the field of usage of solar energy for electric current production.
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Systems design and possibilities of utilization of photovoltaic power station in the Czech Republic
Švec, Radovan ; Procházka, Zdeněk (referee) ; Mastný, Petr (advisor)
This bachelor thesis deals with project and possibilities of use of photovoltaic power stations at the area of the Czech Republic. The first part is dedicated to state and aproach to solar energy in our state and abroad. In the second part are described parts of mecanism used for conversion of solar radiation to electric energy. The third part deals with physical principal of photovoltaic effect. Other parts are dedicated to general project of photovoltaic power station and in the final part economic evaluation of project and joining to the transmission system are mentioned.
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Cell - Phone Effects on Human Health
Pieniažek, Ireneusz ; Křepelka, Václav (referee) ; Filka, Miloslav (advisor)
This bachelor’s thesis is dealing with the influence of cell phones on man. First part is focused on the introduction to the problems of cell phone communication. There are described the frequencies and wave lengths, which the cell phones use. Here is also described the principle of cell phones functioning. Second part is devoted to influence of the cell phones on the human body. It is discussing the electromagnetic compatibility of the biological systems and describing the electromagnetic field occurring in cell phone communications. There are also described the thermal effects of the cell phones and this chapter further discusses the hypothesis about the non-thermal effects of the cell phones. There is a description of mechanism of influence of radio waves. This part also describes the possible health hazards resulting from the use of cell phones and the problem of relationship between the occurrence of cancer and the use of cell phones. There are mentioned other ecological problems connected with cell telephony. Third part is focused on the SAR measurement (specific absorption rate) of the cell phone. Here we can find the definition of SAR. It describes the tested apparatuses, the procedure of measurement and measured values for GSM 900, GSM 1800 and W-CDMA 2000 standards. Tested apparatus in this case is Samsung SGH-Z140V. We can find here technical engineering solutions, which are aimed to minimize the specific absorbing power absorbed by human body during the use of apparatus.
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Detection of ionize radiation with Geiger-Müller tube
Dědina, Radim ; Macků, Jan (referee) ; Musil, Vladislav (advisor)
This work deals with problems related with detection and measuring of the ionisated radiation. First part of this work is devoted to theoretical problems of detection, particulary to measuring with Geiger Muller tubes. Second part of the work contains proposal of electronical circuit using Geiger Muller tube as well as description of results experimentally acquired while using the detector, which was manufactured according to the proposed scheme. On the basis of those results it appears that proposed apparatus can be used for significant indication range extension.
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Nuclear accidents
Mik, Martin ; Suk, Ladislav (referee) ; Vojáčková, Jitka (advisor)
This thesis is a research dealing with nuclear accidents and disasters in the world and us. The work is divided into several parts. The first part deals with the regulation of nuclear safety in the Czech Republic. The second part describes the international INES scale. The last and largest section deals with the actual accidents and disasters.
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Temperature Measurement in Technical Diagnostics
Szmek, Tomáš ; Janečka, Jan (referee) ; Vdoleček, František (advisor)
The purpose of this bachelor’s thesis is to familiarize a reader with possibilities of temperature measurement along with constructions and functions of particular measuring instruments and to present their positive and negative aspects. Both basic contact thermometers used in common life and complex systems (thermovision) employed in the most demanding industrial application are described here. The thesis depicts temperature as a diagnostic value according to which the causes of machinery failures are easily detected and subsequent accidents prevented.
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The formation of biogenic amines in flesh of selected fish species
MATĚJKOVÁ, Kateřina
The thesis deals with the use and effectiveness of some less common methods of conservation of fish meat. The formation of biogenic amines in meat is observed in connection with the non-traditional preservative methods. Amines can serve as indicators of protein degradation. The quality of fish was considered in connection with the increasing content of selected biogenic amines (putrescine, cadaverine, spermidine, spermine, 2-fenylathylamine, histamine, tyramine and tryptamine). Ultra performance liquid chromatography (UPLC) was used as the method for determination of biogenic amines. Amines were derivatized by dansylchloride before their UPLC separation. The fish flesh was vacuum-packed. Samples were stored for several weeks in a thermostat at the selected storage temperature after the application of selected preservative technique. Beta-irradiation and high hydrostatic pressure were used for the preservation of fish flesh. Control samples were not exposed to the â-irradiation and high pressure. The organoleptic properties were studied for all samples (smell/odor, insight and shape). Beta-irradiation was applied to fish meat of common carp (Cyprinus carpio) and rainbow trout (Oncorhynchus mykiss). Both these species of freshwater fish are economically significant. Carp and trout are the species being mostly consumed in the Czech Republic. Fish meat is considered to be provided the flesh is fresh. A testing series of samples was created with common carp to determine the appropriate dose of â-irradiation. The maximum permissible dose of irradiation for fish meat is 3 kGy. Fish samples were exposed this dose in the first experiment. The dose of irradiation was reduced in following experiments based on the experience from the initial experiment. The doses of 0.25, 0.5, 0.75, 1.0 and 2.0 kGy were applied to rainbow trout. The value of 0.75 kGy of â-irradiation or higher (1.0, 2.0 and 3.0 kGy) prolonged the shelf life of fish meat, which was stored for three months (98 days). Prolonging of the shelf life of fish meat to approximately 98 days at 3.5 °C is redundant from technical point of view. For that reason lower doses 0.25, 0.5 and 0.75 kGy were tested in more detail in the repeated experiment with carp meat. Lower doses of â-irradiation are considered to be more acceptable and-at the same time-sufficiently effective for delaying the beginning of degradation processes. 6 High hydrostatic pressure was applied to meat of common carp (Cyprinus carpio), rainbow trout (Oncorhynchus mykiss) and pike (Exos lucius). Pike is another very popular kind of freshwater fish. Pike flesh is very tasty, but in spite of this, pike is not so much popular among consumers compared to carp and trout. The cause is its high price. Samples of pike were stored at standard temperature 3.5 °C and also at higher temperature 12 °C (unlike experiments with â-irradiation). Lower temperature of storage (3.5 °C) followed the conditions of storing of fish meat in industrial refrigeration facilities and households. The high pressure might not be sufficient for preservation at higher storage temperatures. This assumption was based on available information. Samples were treated by high pressure and stored at both 3.5 °C and 12 °C to verify this assumption. Higher temperature simulated either failure of refrigeration equipment or unsuitable store temperature of meat. In all species selected freshwater fish two levels of high pressure were applied ? 300 and 500 MPa. Both levels had significantly reduced the formation of biogenic amines, especially in samples stored at 3.5 °C. At this temperature, the effect of 300 and 500 MPa delayed start of degradation processes in fish meat by 3?4 weeks. At 12 °C and 500 MPa, high pressure extended the sustainability of meat by no more than one week. 500 MPa is effective treatment at the lower temperature of 3.5 °C. High pressure is not reliable preservative techniques at higher temperature.
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Detection of Ionizing Radiation in Radiological Controlled Area of Nuclear Power Plant Temelín.
DOUDOVÁ, Vendula
The power plant Temelin is equipped with the modern system of radiation control. The system meets high technical standard. It ensures the control of all parameters according requirements of our legislative and government authority. The system provides the control in such dimension to have necessary information about irradiation of workers and the population in neighbourhood, outlets to environment, and about the situation in the some selected technological circuits and systems. It is necessary to monitor the integrity of barriers in every mode of power plant Temelin including emergency and post-emergency conditions. The working environment in contained area of the power plant Temelin is monitored with stationary monitoring system and with the mobile instruments according the approved operational manual. The workplace monitoring is realized with surveillance, measurement, evaluation and recording parameters of ionizing radiation field and the occurrence of radionuclides in working area, especially the dose equivalent on the working area and the volume activities in the environment and the surface activities.
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