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Filtration in digital radiology
SVITÁKOVÁ, Eva
Filtration in digital radiology The bachelor´s degree work especially deals with importance of filtration in the resulting quality of an X-ray image. It describes the creation, properties and interactions of X-rays with mass, creation of an X-ray image, and parameters and factors that influence its quality. The main part of the degree work involves the monitoring of changes in the quality of an X-ray image while using a filter-type equalizer and under the conditions of measuring with a homogeneous phantom; further, under the same conditions while measuring with an anthropomorphous phantom, and also the comparing of quality of an image of several groups of patients while using a filter and without using a filter. The outcome of the degree work is a tabular representation of the measured and processed values and their evaluation.
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Coordinate measuring machines
Palásek, Vítězslav ; Zachoval, Luboš (referee) ; Zachoval, Luboš (referee) ; Pernikář, Jiří (advisor)
This graduation work is about co-ordinal measuring machines (CMM) with optical reader system and optical CMM. In accordance with submission and in terms of survival well known contactless systems the direction is to make methodology objective classification of rating with granting summary of these systems. The first part contains optical principles for visual scanner in CMM and optical CMM. Ist is described there principle of contactless obtaining steric digital version of measured object with using laser and optical facilities. The second part contains brief makes survey of these contactless systems and their component which are used for co-ordinal measuring. The survey is devided into optical readers, which are put on CMM brake or on mobile measuring brake and on optical CMM, which localize position measuring/sensing head in the space or they read measured object from specific distance – fotogrammetric. Characteristic of offered systems and chart with technical data are mentioned with each maker. The third and fourth part is about submission methodology for objective choice suitable sort of reader, optical CMM in target of characteristic reader system quality. And from this methodology is given the choice of suitable exponent stationary measuring machine with contact and contactless way of reading and their comparison.
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Contribution to the evaluation of different approaches to the modelling of soil loss by water erosion in GIS
Hrabalíková, Michaela ; Janeček, Miloslav (advisor) ; Jan, Jan (referee)
Dissertation thesis: Contribution to the evaluation of different approaches to the modelling of soil loss by water erosion in GIS, is a set of five studies published or accepted for publication in scientific journals. Thematically the work deals with the question of linking the erosion modelling together with geographic information systems. The work is divided into five chapters. In the first chapter, the issue of erosion and rainfall-runoff modelling is described. A particular focus is placed on the concept and the basic equations underlying erosion modelling. The second chapter contains 2 studies that deal with modelling rainfall-runoff conditions in the area of experimental area using KINFIL model. The chapter also discusses the selection of a suitable model and source datasets that forms the basis for the evaluation of physiographic parameters of a catchment. The third chapter is thematically focused in calculating the rainfall factor based on long-term precipitation records from 32 meteorological stations in the Czech Republic. It partially overlaps with the previous chapter because one of the outcomes of the study is the REDES database containing values of R-factor. However, the chapter focuses more on the time scale, and especially the influence of the time step in the simulation on resulting outcomes of the model. The fourth chapter is dealing by erosion modelling in GIS based on analysis of digital terrain models. It contains a study that addresses the influence of various algorithms and/or equations to calculate topographical factor and its effect on the overall prediction of soil loss.
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Advanced Security Methods of Medical Image
Roček, Aleš ; Šimák, Boris (referee) ; Molnár, Karol (referee) ; Dostál, Otto (advisor)
Medical institutions adapt digital based archiving of patients records images to fulfil its advantages like availability, easy sharing, high resolution etc. Digital form of records brings apart from advantages also disadvantages at security risks. It is easier attacking, stealing, using without authorization etc. This thesiss deals with this security issues, describes the needs and approaches to security, explains the reasons for deployment of watermarking. It names three main methods of medical image watermarking and compares their plus and cons: zero, reversible and watermarking in Region Of Non Interest (RONI). New method of Zero-reversible-RONI watermarking, that combine advantages of described methods, is proposed. For practical tests of properities of proposed method was used huge database of medical images. Application of the proposed method on this database delivers very promising results. Practical results discussion and comparison with other medical imaging watermarkikng methods are at the end of this thesis.
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Verification of Properties of WiFi IEEE 802.11n
Alexa, Jan ; Miloš, Jiří (referee) ; Kuder, Zenon (advisor)
This bachelor thesis deals with wireless systems of IEEE 802.11 standards. This thesis explains the fundamental terms and principles, which are relating to digital wireless systems. This thesis is structured into four thematic units. The first chapter discusses an introducing with Wi-Fi standard – IEEE 802.11 in general. Second part contains a deeper focus on modern standards 'n' and 'ac', showing the main differences and innovation compared to older standards 'b', 'g', 'a'. Further in this part of the thesis is described using of MIMO technology. The third chapter contains an analysis and description of the application, which is part of the thesis. The fourth part is detailed focused on to the design of laboratory tasks for teaching at the undergraduate level, which demonstrates the use of MIMO technology.
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Image digitalization in radio diagnostics and application in mammography
Glatzner, Miloš ; Slanina, Martin (referee) ; Frýza, Tomáš (advisor)
The aim of this study was to analyze issues on digitalization in radiology, especially in mammography. Definition of the separate parts of the diagnostic chain with special accent on mammography imaging with several mammography digitalization designs according to various conditions is stated in the first part of the paper. Comparison between CR and DR systems is then provided in term of patient dose and in term of diagnostic efficacy followed by corresponding conclusions and recommendations. Further is being discussed the methodology of quality assurance in digital mammography. Methodics of single tests is adapted from European guidelines for quality assurance in breast cancer screening and diagnosis [7]. Set of tests enlisted in short-term stability tests national system is selected on the basis of recommended intervals and our specific conditions as described in the paper. Selected test were implemented into „ZPS“ software (VF a.s.) as a new module – digital mammography. This method is supposed to be optimal for a practical utilization, because several radiology departments already use this user friendly software, which also enables to follow the changes in legislation.
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Artificial neural networks for pattern recognition
Kukačka, Marek ; Božovský, Petr (referee) ; Mrázová, Iveta (advisor)
This work describes the advantages and disadvantages of using neural networks for pattern recognition. Several neural network models are described and their use for pattern recognition is demonstrated. Standard multi-layered perceptron model is compared to a more sophisticated convolutional network model. A new network model is introduced, which is inspired by the convolutional networks and aimed at rectifying some of their shortcomings. The work describes results of tests performed with the described network model on the problem of recognizing hand-written digits.
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Genetic Regulation of Limb Development
Šnajdr, Pavel ; Grim, Miloš (advisor) ; Peterka, Miroslav (referee) ; Slípka, Jaroslav (referee)
Lx in SHR.Lx rat manifests in homozygotes as hindlimb preaxial polydactyly. We showed that a 2,964-bp deletion in Plzf (Promyelocytic leukemia zinc finger) intron 2 is the only candidate for Lx. The deletion removes the most deeply conserved CNE with putative regulatory influence on Plzf expression. Using in situ hybridization we found reduced expression pattern of Plzf in Lx/Lx limb and anterior expansion of expression domains of Plzf targets Hoxd10-13 genes and Bmp2, in the absence of ectopic Shh expression. Rat hd manifests in homozygotes as reduction or loss of digits II and III on both hind and forelimb and impairment of spermatogenesis leading to male infertility. We showed that hd mutation is caused by an insertion of an endogenous retrovirus into intron 10 of the Cntrob gene resulting in the translation of a truncated protein. In situ hybridization showed that expression of cartilage condensation marker Sox9, and Bmp receptor Bmpr1b is absent from the distal parts of the digit condensations II and III. Studying spermatogenesis we showed that centrobin (protein of Cntrob) localizes to the centrosome, manchette, and the marginal ring of the spermatid acroplaxome. Mutant spermatids show a disruption of head-tail coupling apparatus leading to spermatid decapitation . We demonstrated distinct...
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Imaging methods in assesment of the scoliotic children spine deformities
HLADÍKOVÁ, Ilona
Long-term effects of static load and lack of physical activity in children leads to the formation of poor posture, which is nowadays more and more often. Orthopedic deformity arising in childhood is usually reflected the after-effects in adulthood. It is useful and important these deformities early recognition and capture in order to prevent the progression of many diseases. In that radiology has an irreplaceable role. The work entitled " Imaging the investigation scoliosis spinal child deformity" approaching the issue of damage to children´s spine scoliosis mainly children, and thein investigation by imaging methods. At the beginning of my work, I reminded the anatomy and physiology of the spine. Then I described the division and types of scoliosis. The rapid development of imaging techniques and new in the last few decades have brought about changes in imaging the spine. I described the principle of the methods that are applied in the examination of the spine. Great progress for the entire radiology and changes in working practices radiology assistants brought digitization. Therefore, for the mention in my work and I compare it with conventional analog radiology. Investigation of children have thein own characteristics and pediatric radiology I devoted a separate chapter. In chapter radiation protection, I described the basic principles of protection against harmful ionizing radiation, I mentioned the valid legislation, the basic units and quantities in radiation protection. The aim of my thesis is to test children´s scoliosis spine, to compare the frequency of examination methods of diagnosis. As the second goal I set to compare the radiation exposure in children´s spine examination on an analog meter compared to tests on digital devices. The first objective is building on the hypothesis that even today, despite the development of new diagnostic methods such as CT, MR, ultrasound, radiographic examination remains the priority children´s spine. The second objective I hypothesized that due to the digitization of the radiation dose to the patient during the examination decreased. Quantitative research was conducted at University Hospital Motol. Number of examined children´s backbone has shown that the vast majority of children with deformities of the spine radiography was investigated. Hypothesis number one is hereby confirmed. To meet the second objective, I selected group of 30 children diagnosed with idiopathic scoliosis, which in 2008 was on the unit Chiralux 2 (6a) conducted an analog image of the spine. In the same way, I chose a group of 30 children examined in the first half of 2013 on the same site digital radiography unit at Siemens Ysio 2 Fluorospot Compact. This was possible because in 2009 there was a baby Radiodiagnostics FN Motol direct digitization. The parameters used in tests I averaged a further mathematically processed. Hypothesis number two was also fulfilled, since calculations have shown that the examination of the spine digital radiography, radiation to the child about 31,3% lower. In my work I have in addition included the calculation of radiation doses received by the mammary gland during radiographic examination of the spine in the AP and PA projection. It turned out that the values are significantly different. This finding is in terms of radiation protection relatively important, since the ICRP in its recommendation to increase the value of tissue weighting factor for the mammary gland. Investigation of children imaging using ionizing radiation is the radiation dose to the child. Radiology assistant by its qualified work experience and contribute to this burden is as low as possible.
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