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Laboratory exercise for RTG imaging systems
Kuchař, Otakar ; Macíček, Ondřej (referee) ; Mézl, Martin (advisor)
The aim of this Bachelor thesis is to study the X-ray and computed tomography. The theoretical section explains the basic physical principles, elementary particle, atom and ionizing. The following parts of the thesis deal with topics from the origin and various types of X-ray, to interaction of X-ray with tissue and X-ray detection. For computed tomography the thesis also explains data collection, the reconstruction of image using simple back projection, filtered back projection and algebraic reconstruction. In the practical part are analysed several measurements which were taken in the X-ray chamber designed for educational purposes by Leybold. The topics solve the attenuation of X-rays depending on the type and thickness of the material and the spectrum of the X-ray radiation. In the field of computerized tomography solve tasks as the change of contrast, parameters of acquisition and methods for reconstruction. The work includes prepared sample solutions to a laboratory experiments.
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Emerging Trends in Dendrochronology
Horáček, Tomáš ; Neuwirthová, Ludmila (referee) ; Mikulka, Jan (advisor)
Tato práce se zabývá popisem současných a experimentálních metod odběru vzorků pomocí presslerova nebozezu, výřezů z kmene, fotografie, rentgenu, počítačové tomografie a magnetické rezonance na poli dendrochronologického výzkumu. V práci jsou rozebírány destruktivní a nedesktruktivní metody odběru vzorků. Je také kladen důraz na původ vzorků: zdali je možno využít destruktivní metody nebo zdali je to nemožné jako v případě vzácných archeologických objektů. Dále popisuje standardní optometrickou metody a další experimentální metody fungujicí na principu kontranstního zpracování obrazu za účelem rozeznání letokruhů. V práci jsou také popsány různé druhy metod softwarového zpracovnání kde jako vstup slouží buď série dat nebo obraz letokruhů. Další rozdíly tvoří vymezené spektrum uvedených prací, některé práce se zaměřují na zpracování obrazu od píky tedy od pořízené fotografie až po hotové datovaní, některé však zajímá pouze úzký sektor dendrochronologie jako jsou například vady či špatně rozeznatelné letokruhy.
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Design of computer tomograph
Bojková, Eva ; Lehocký, Peter (referee) ; Zvonek, Miroslav (advisor)
The graduation thesis is engaged in the design of computed tomography (CT). It is a piece of medical equipment which helps to define the diagnosis of a patient. The first part of the project is a research into contemporary stage and production of CT systems. Consequently the new design of computed tomography is designed in a way to maximise ergonomical, technical and aesthetic quality.
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Properties and the Use of Metal Foams
Křivánek, Robin ; Liškutín, Petr (referee) ; Němec, Karel (advisor)
In this thesis are summarized the findings of metal foams, with prevailing constraints on aluminum foam, because in them hides the greatest potential. The first part is described the production of porous materials, especially the way of floam production by thermal decomposition of floaming agent and melt gas injection. There are also written stress tests to gain a deeper knowledge of their properties, but also the latest exploring methods of foams, such as using a radioscopiy and CT scanner from which then creates a voxel model of foam. They are summarized here the basic ways of processing. Finally we must mention the possibility of using these materials with a focus on commercially produced foams Alporas® and Duocel®. Mass using foams mainly prevents high production costs and in some cases difficult reproducibility of properties.
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Application of non-destructive methods determining the quality of glued wood bondlines
Dvořáková, Martina ; Brožovský, Jiří (referee) ; Vaněrek, Jan (advisor)
The presented bachelor thesis is focused on the evaluation of timber elements by using non-destructive methods which are intended for the evaluation of glue lines. The main part of the work is focused on summarizing and the detailed description of selected non-destructive methods which can be used for glue line evaluation. There is also carried out the researche of selected scientific articles describing the application of non-destructive methods with regard to the evaluation of timber elements.
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Radiation load patients during lung skiagraphy
NOVÁKOVÁ, Andrea
The topic of my thesis was to evaluate radiation doses to patients with lung skigrafii. The impetus for the treatment of this topic was that even though the Ministry of Health of the Czech Republic (Věštník MZ ČR 9/2011) recommends the use of classic hard skigrafii lung imaging technique, a number of radiodiagnostic workplaces still uses the technique of low voltage, although the patient is exposed to a higher dose. Skigrafie lung examination is among the low-dose exposure, but it is the most commonly performed tests. Since the risks of radiation from various sources of radiation during their lives constantly in the body are added, it is necessary to try to make at least a medical exposures are minimized as much as possible. In the theoretical part I tried to arrange the all important information on x-rays, skiagrafii, lung anatomy, imaging techniques, radiation protection and legislative framework that deals radiodiagnostika. Department of Radiology in the Czech Republic have at their disposal guidelines and recommendations for proper X-ray examinations, called. National Radiological standards that ensure optimum image quality while minimizing the radiation dose for the patient. For physicians who indicate radiodiagnostic examinations is crucial document "Indication criteria for imaging", which sets criteria so that all examinations imaging methods were duly substantiated, and their indications regulated. Practical work is focused on comparing the radiation burden of two imaging techniques for the examination of the lungs, namely imaging technique compared with low (ie. Soft) and high (ie. Hard) exposure voltage. The main part is based on the processing of results and input values falling surface kerma, which were measured for X-ray work by a water phantom ionization chamber using two exposure techniques. Based oriented values and using tabulated values I calculated the dose for each imaging technique. The effective dose for soft imaging technique was almost three times higher than the technique hard. Also interesting is the result of secondary radiation, the soft technique is almost five times exceeds the emerging secondary radiation hard imaging technique. Another important part of this work was to compare the effective doses for the two groups of selected patients with radiographic examination of the lungs, were divided according to the used imaging technique. The first group of patients who were imaged in the first quarter of 2014 equipment with voltage 125kV, in the second group were patients from the first quarter of 2011 the average radiography exposure voltage 57.2 kV. From both groups were selected only patients with a weight of 60-80 kg, which approximates the patient's usual layout, with whom works legislation Ministry of Health. The effective dose for hard imaging technique for the examination is 0.0085 mSv, for a soft technique is effective dose equal to 0.0304 mSv. It follows that the effective dose for hard skigrafické imaging technique for examination of the lungs during soft imaging technique is 3.5 times higher than in the technique hard. In terms of radiation protection is also interesting, as shown in the calculation of benefits program PCXMC that the dose to the gonads when skigrafické examination of the lungs almost zero, therefore the use of protective equipment in the genitals during the examination pointless and rather plays a psychological role. The aim of this thesis was to demonstrate that the advised the Ministry of Health of the Czech Republic on the transition from soft to hard imaging technique technique is justified. On the basis of unmeasured values and progressive processing of results I could confirm my hypothesis: Using hard imaging technique at skigrafii lungs is reduced patient radiation dose.
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Bone traumatology
DOLEŽALOVÁ, Barbora
The subject of the bachelor?s work is ?Bone traumatology?, which is in health institutions of the Czech Republic classified forefront in diagnostics thanks to skiagraphy. In nowadays medicine new technologies are used permanently. Dealed with conventional radiology, its the biggest expansion came in the beginning of 20 century, when some new radiation X (X-ray radiation) was discovered. Just thanks to this discovery the new era of permanently developing new methods for diagnostics started. The theoretical part of the work is concerned with anatomy of a bone together with traumatology. Next there is a part dedicated to some basic facts about X-ray radiation. In this work is also described skiagraphy, in which I deal more with the matters of film material and digital radiology. In hospitals and in majority of workplaces we meet more and more digitalisation of a system and a transition from film materials to various detectors (an image intensifier, semiconductor detectors, photostimulable phosphor plate etc.,). The aim of the work is to analyse a quotient of skiagraphy of bone traumatology in particular age groups. The hypotheses of this bachelor?s work were defined this way: in radiodiagnostic wards predominates skiagraphy of an axial skeleton over other radiographic diagnostics (soft tissues- lungs, a heart, an abdomen). The most numerous group of examined people are children at the age to 15. The practical part of the work provides information dealed mainly with numbers of radiographic exeminations performed in the X-ray workplace in Týn nad Vltavou from 2009 to 2011. These examinations were concerned with bones, but also soft tissues (a heart, lungs, an abdomen). The data were found out from operative diaries and computer systems. In this work there were compared patients of particular age groups: - in the number of radiographic examinations in an observed period (2009-2011) - in the number of radiographicly, examined particular zones of a human body (a hearth+lungs, a spine, an upper limb, a lower limb, a skull, ribs+a breastbone and an abdomen). Further data which was obtained from the internet portal of Institute of health information and statistics of the Czech Republic (ÚZIS ČR) were worked up. Examinations were tested through the use of imaging technologies in the Czech Rebublic and Southern Bohemia and a number of radiographic examined particular zones of a human body (a breast,a lower limb, an upper limb, a spine, bone radiology and an abdomen) in Southern Bohemia from 2009 to 2011. All the obtained data I worked up into particular graphs which are found in the chapter ?Quantitative research?. In the chapter ?Discussion? particular graphs are described and are complemented with my personal hypothesis and opinions of a radiology asistent from X-ray workplace in Týn nad Vltavou. The results of the work prove that the aim of the work was realised. Defined hypothesis no.1: in radiological workplaces skiagraphy of an axial skeleton prevails over the other radiographic diagnosis (soft tissues- a heart, lungs, an abdomen) was confirmed, however hypothesis no.2: the most numerous group of examined are children to the age of 15 was not succesful to confirm. In the chapter ?Conclusion? I summarised the results of the work, which will help as a supplemental statistical material with a more detailed structure in X-ray workplace in Týn nad Vltavou. The theoretical part of the work can be used as a tutorial material not only in the subject of the radiological assistant.
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Acceptability of X-ray security controls at the airports
Heriban, Josef ; Druláková, Radka (advisor) ; Dubský, Zbyněk (referee)
Security controls at airports using full-body scanners based on X-rays which have been installed by states since the experience with September 11, 2001 and with other terrorist attacks invoke debates in both professional and social-wide circle. The acceptability for society is discussed having a core role in its health, economic, ethic or politic aspects. The aspiration of this bachelor thesis stem from global evaluation of all those aspects interconnected with legal settings of such measures. Special attention belongs to the United States and Europe, representing the west cultural area, which are the most often addressees of contemporary terrorism.
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Modulace HFQPO
Bursa, Michal
We study strong-gravity effects on modulation of radiation emerging from accreting compact objects as a possible mechanism for flux modulation in QPOs.
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O vzájemných vazbách mezi kHz QPOs
Török, G. ; Bursa, Michal ; Horák, Jiří ; Stuchlík, Z. ; Bakala, P.
We further investigate the issue of kHz QPO frequency ratios in neutron star low mass X-ray binaries. In this note we report on recent analysis of occurrences and properties of kHz QPOs in the source 4U1636-53. Assuming that kHz QPOs occur in pairs whose frequencies are linearly correlated, we find a prominent frequency range that separates upper and lower QPO observations.
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