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Flood protection and flood plans on selected basin of the Lužnice river
KUKAČKOVÁ, Lucie
The thesis consists of two parts - the theoretical outline and the research. The theoretical section describes in general the topic of floods, protection of the population against floods, flood control measures, flood plans and legislation related to floods. The last chapter of the theoretical section is focused specifically on the Lužnice river and the affected municipalities, in which qualitative research took place. These are the villages of Vlkov, Veselí nad Lužnicí, Dráchov and Soběslav. In order to fulfil the aim of this thesis, it was necessary to acquire not only flood plans of the affected municipalities, but also other non-public documents, and to thoroughly analyze and compare them with each other. Based on this analysis and comparison, information was compiled concerning flood protection measures in the municipalities, where the investigation took place. This comprehensive information is presented in chapter 'Results'. During the qualitative research, several errors and shortcomings were uncovered in the flood plans of municipalities in the Lužnice river basin. Shortcomings were discovered mainly in the continuity of flood plans and in the absence of endangered objects, which should be listed in flood plans. These objects pose anthropogenic risks to municipalities. Others shortcomings were found in food plans updates. These updates should be performed regulary but this is not happen in practice. For example food plan of the village Vlkov is 22 years old and has been update only once. During the examination of the official websites of the municipalities, other shortcomings were found in the information available to the population. The actual investigation and analysis of the flood plans provided an answer to the research question. Individual flood plans and flood control measures are not in concord.
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The Difference between Planed and Real Measured Dose under the Bolus Made of New Material
KUKAČKOVÁ, Lucie
The first chapter of the theoretical part of the bachelor's thesis outlines radiotherapy in general. Radiotherapy is a clinical treatment using ionising radiation to treat malignant and benign diseases. It is one of the youngest medical disciplines. The development of radiotherapy began in November 1895, when Wilhelm Conrad Röntgen discovered X-rays. Radiotherapy became an independent medical specialty in 1922. The second chapter describes planning in radiotherapy. Irradiation plans for radiotherapy are created on the basis of a planning system. ECLIPSE planning system is used in the oncology department in České Budějovice Hospital. Phantoms are the theme of the third chapter. Phantoms are materials whose radiation absorption corresponds to human tissue. Water is a basic universal phantom material. In addition to water, also other materials are used, such as polystyrene, plexiglass, paraffin, PMMA etc. The last, fourth chapter of the theoretical part, deals with boluses. Boluses are tissue-equivalent materials that are put on the patient's skin during irradiation when it is needed to increase the surface dose and at the same decrease the depth dose. Moreover, bolus is used to compensate the missing tissue. Bolus is most often used to diagnose patients after mastectomy due to breast cancer. The most important characteristic of boluses is their ability to absorb radiation. In the oncology department in České Budějovice Hospital, bolus from dental wax Ceradent had been used before. A bolus made from this material was hard and uneasy to shape. That is why it did not fit tightly to the chest wall of the patient. For this reason a new line of boluses was obtained for the oncology department, from gel material supplied by CIVCO company with dimensions 30 x 30 cm and thickness 0.3 cm, 0.5 cm and 1 cm, in "skin" and "skinless" version. These new boluses stick easily to the patient's skin and copy the shape of the body. The first objective of my bachelor's thesis was to compare the doses planned and measured under the bolus from the new material. This objective is elaborated in the practical part of the bachelor's thesis in chapter presenting the results. Another objective was to elaborate the principles for the use of bolus. These principles are described in the theoretical part of the bachelor's thesis in chapter describing the use of bolus in radiotherapy. The following hypothesis was suggested in the thesis: "It can be assumed that the generated bolus in the planning system corresponds to the scanned bolus on the CT with patient and that there is a difference between the planned dose and measured one." To confirm or refute the working hypothesis, measuring was executed in the oncology department in České Budějovice Hospital. Data about individual doses were collected boluses generated in the Eclipse planning system of different width (0.3 cm, 0.5 cm, 1 cm) on phantoms. Three types of phantoms from PMMA were used for the purposes of this measuring. First, the measuring was executed on phantom in the shape of the chest wall of a patient after breast ablation. Then, the tabular phantom and universal IMRT verification phantoms were used. The measurement was executed on the Clinac 2100 C/D linear accelerator, later on the new TrueBeam 2.5. linear accelerator. All these doses were measured by ionisation chamber from PTW company with volume of 0.125cm3. The obtained data were processed in tables and deviations of individual doses were calculated. Based on this measurement it was found out that the deviations of all doses are less than 3%. And therefore also the hypothesis of the thesis was confirmed. There really is a difference between individual doses, but not so significant to affect the size of dose during the planning. As for the practical outcome, generated boluses will be used as standard in the oncology department in České Budějovice Hospital.
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