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Digital radiography- image processing simulation
Lamoš, Martin ; Kolář, Radim (referee) ; Drastich, Aleš (advisor)
This paper describes a MATLAB application with the main purpose of the simulation of noise components and noise elimination methods of Digital Radiography. The main parts of simulator are the model of a scene, procedures for loading the noise components to image data and methods for image processing. Various methods are employed depending on the type of noise. Subtraction techniques are used for the elimination of structural noise. The physical noise suppression is obtained using several methods of cumulation and Pixel Shift is used to reduce motion artifacts caused by the existence of moving noise. The techniques of superposition highlight the areas of interest in an image. Included are also auxiliary procedures for simulator running and presentation of final data. The model and the presented application can be used mainly for educational purposes as a powerful didactic tool.
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Modern trends in radiographic procedures and methods in defectoscopy
Skřivánková, Vendula ; Vlašic, František (referee) ; Juliš, Martin (advisor)
Presented thesis deals with modern trends and techniques in radiographic methods of crack detection which are recently used in engineering practice. In the first part, conventional (analogue) radiography principles based on creating a visible image of tested object to radiographic film are discussed. The next part is aimed to the digital radiography and radioscopy. To digitize existing X-ray film images, application of storage phosphor plates (CR), flat panels (DR) and computed tomography (CT).
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Digital radiography- image processing simulation
Lamoš, Martin ; Kolář, Radim (referee) ; Drastich, Aleš (advisor)
This paper describes a MATLAB application with the main purpose of the simulation of noise components and noise elimination methods of Digital Radiography. The main parts of simulator are the model of a scene, procedures for loading the noise components to image data and methods for image processing. Various methods are employed depending on the type of noise. Subtraction techniques are used for the elimination of structural noise. The physical noise suppression is obtained using several methods of cumulation and Pixel Shift is used to reduce motion artifacts caused by the existence of moving noise. The techniques of superposition highlight the areas of interest in an image. Included are also auxiliary procedures for simulator running and presentation of final data. The model and the presented application can be used mainly for educational purposes as a powerful didactic tool.
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Modern trends in radiographic procedures and methods in defectoscopy
Skřivánková, Vendula ; Vlašic, František (referee) ; Juliš, Martin (advisor)
Presented thesis deals with modern trends and techniques in radiographic methods of crack detection which are recently used in engineering practice. In the first part, conventional (analogue) radiography principles based on creating a visible image of tested object to radiographic film are discussed. The next part is aimed to the digital radiography and radioscopy. To digitize existing X-ray film images, application of storage phosphor plates (CR), flat panels (DR) and computed tomography (CT).
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RADIATION PATIENT LOAD IN DIGITAL AND CONVENTIONAL RADIOGRAPHY
KRAINA, Aleš
To implement a digital service essentially means transition from the established SFR technique (i.e. screen-film radiography) to predominantly CR (Computed Radiography) or DR (Direct Radiography). The stated methods of digitalization differ in their use of a range of types of diagnostic equipment and image digitalization devices. The utilization of individual methods can, however, lead to different results in the amount of skin entry radiation dose and organs absorbed dose in patients undergoing ionizing radiation examination. The objective of this thesis is to compare individual methods (i.e. SFR, CR, DR) generally used for image digitalization in respect of radiation stress for patients. Radiation stress was compared both by measuring entry radiation dose on phantoms and by clinical results acquired from a KAP meter. To validate clinical results, the three most often examinations have been chosen: skull, chest, and stomach examinations. This selection was affected by its frequency and amount of radiation stress. The measured results were then compared with available foreign literature. On the basis of the measurements acquired, it is apparent that Direct Radiography leads to radical reduction in radiation dose in patients. As regards Computed Radiography, it cannot be generally said whether it entails a lower dose in patients. The measured and consequently published figures imply that there are significant differences amongst individual manufactures of CR systems (for example Fuji, Kodak, Konica, etc.) which do or do not lead, in comparison with SFR, to a lower radiation stress. According to the measurements published in this thesis, it can be stated that the use of state-of-the art CR technology could lead to reduction as high as 50 percent of the radiation stress if compared to SFR.
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The ambulatory radiology institution - the transition from the analog to the digital system
DOUCHOVÁ, Irena
This work offers general information about digitizing an outpatient radiodiagnostic department. It presents physical principles of digital imaging and the equipment that is necessary for the transition to a new technology. The introduction explains the functional principle of memory foils, digitizers and data archiving. Some attention is also paid to economic and organizational problems related to maintaining partial operation of the analogue system at a digitalized department. At the same time, some mistakes are described that can be eliminated having greater knowledge of the system of work at a digitalized department. A comparison of the amount of finance expended on chemicals, films and servicing of a developing automatic machine with operating costs after digitizing led me to a conclusion that the cost of digitizing will not return after five years by saving finance related to the analogue process. Most of the memory foils have to be replaced after four years due to their ``worn-outness{\crqq}. The most important benefit digitizing brings is the improvement and acceleration of the access to information, which means saving of labour time. The new technology makes it possible to shorten the time of examination helping thus in critical situations.
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