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Residual life assessment of hydrogen adsorption vessel subjected to cyclic loading
Brančan, Peter ; Vincour, Dušan (referee) ; Létal, Tomáš (advisor)
There was a need to asses the residual life of a cyclically pressurized adsorber of PSA unit used for the separation of hydrogen gas from a feedstock mixture, of which designed lifetime according to outdated standart ČSN 69 0010-4.20 was exceeded. The maximum design life was determined according to more recent design codes by the methodology of fatigue curves and comparison of results of outdated standard and 3 newer standards: EN 13445-3 - clause 17 and clause 18, and ASME BPVC Section VIII Div.2 - Level 2 was made. Due to the exceeding of the design life results by all of the standards the alternative approach of Fitness for service method based on linear elastic fracture mechanics of crack growth with the assumption of the occurrence of non-detectable defect size was used. The crack growth parameters were adjusted according to the study of crack propagation in hydrogen environment and implemented into the calculation of API-579-1/ASME FFS-1 Fitness for Service standard. The results showed, that pressure vessel can be further operated if regular NDT inspections are made. Inspection intervals of critical positions were determined from these results with compliance to safety and, at the same time, the scope of inspections has been modified to reduce expenses of carrying them out.
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Probabilistic safety assessment of operation
Jordánová, Petra ; Mladý, Ondřej (referee) ; Kotek, Luboš (advisor)
This thesis deals with the method of modelling event trees and fault trees within the probabilistic safety assessment at the Dukovany nuclear power plant. In the first part, probabilistic safety assessment is presented, along with a description of the used analyses, specifically ETA and FTA, and the software used for development of probabilistic models at nuclear power plants in the Czech Republic. Then Large LOCA accident is described, for which a pilot model is developed in the second part of this thesis. The main aim of this thesis is a replacement of the original modelling method with a new modelling. The presented method focuses, in addition to a development of event trees and fault trees, primarily on the substitution of previously used house event for initiating events. In order to prove correctness of the created model, the cut sets from both models are compared. The benefit of the work is the elaboration of a pilot model that utilizes a different modelling method. Thanks to the presented modelling method, the existing number of event trees can be significantly reduced, and manual setting of house events can be removed. This approach simplifies the work with the model and shortens the calculation time.
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Upgrading biogas by PSA
Krhut, Štěpán ; Havlásek, Martin (referee) ; Zejda, Vojtěch (advisor)
This work deals with bio gas cleaning by a PSA method and modernizing of a laboratory unit. Raw bio gas contains many unwanted elements like carbon dioxide mostly which lowers its energy potential then. To extend the possibilities of usage of bio gas it is necessary to remove such elements. One of the well-known method for eliminating CO2 out of the bio gas is the method called Pressure Swing Adsorption (PSA). This work describes PSA method and compares it with other methods for cleaning the bio gas. In the following part of my work I am introducing the original laboratory PSA unit which is placed in the laboratory of UPI institution for research purposes. The modernization of the method was made by changing the manual valves for electromagnetic ones and there was also designed a new control system unit for two control modes. For manual and for automatic. The essential function is based on remote controlling the valves either by switches or by a program. The electric control panel was created for such required modes. The automated process was controlled by Arduino programming platform which was integrated into the panel. In the case of the next measurement and reading there was created a detailed description for user on how to operate the control panel and also the comments for control program of automatization.
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Approach to the nuclaer safety of the 3rd generation nuclear reactors
Pavlíček, Michal ; Kolář, Jaroslav (referee) ; Kolář, Jaroslav (referee) ; Matal, Oldřich (advisor)
The main target of the master´s thesis is reviewing the generation III nuclear reactors in term of the nuclear safety. At first we have to learn some theory of the nuclear safety in order to understand safety systems of the generation III nuclear reactors. Therefore the thesis is divided into two parts. Legislative and technical approaches to nuclear safety are mentioned in the first part. Regulatory bodies, whose task is to supervise nuclear safety in the nuclear power plants, belongs to the legislative approaches. There are defined terms such as defence in depth, redundancy, diversity, etc. There are mentioned methods to assessing nuclear safety – deterministic and probabilistic methods, especially probabilistic methods, for which a simple example is provided. There are also mentioned active and passive safety systems and their significance for nuclear safety and inherent safety too. There is an example of the function of the active and passive safety systems of the EDU nuclear power plant in conclusion of this issue. The second part deals with description of the selected nuclear reactors in context of the construction of the new units of nuclear power plant in Temelín. The nuclear reactors from companies, which applied for the public tender opened by ČEZ, a. s., for the construction of the ETE 3+4. Thus, the nuclear reactor MIR-1200 by ATOMSTROYEXPORT (Russian Federation), the nuclear reactor AP1000 by WESTINGHOUSE (USA) and the nuclear reactor EPR by AREVA (France) are taken into account . Comparison of the generation II and these generation III+ nuclear reactors necessarily belongs to this master´s thesis. These the generation III+ nuclear reactors are compared with the nuclear reactor VVER 440 (EDU) and in particular with the nuclear reactor VVER 1000, which is operated in the nuclear power plant Temelín. The final chapter contains generally appraisal of the whole problem.
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The diagnostic and prognostic ability of selected serum and urinary markers of prostate cancer
Do Carmo Silva, Joana Isabel ; Veselý, Štěpán (advisor) ; Čapoun, Otakar (referee) ; Fedorko, Michal (referee)
The diagnostic and prognostic ability of selected serum and urinary markers of prostate cancer Abstract Serum prostate specific antigen (PSA) is the only widely approved marker in prostate cancer (PC) diagnosis and follow up after treatment. Its role has remained controversial due to lack of specificity and the risk of overdiagnosis of insignificant PC. The aim of this work was to explore promising markers of PC and to improve current patient stratification to adjuvant treatment. Three main studies were performed using different media (urine and serum). The first study included the evaluation of Engrailed-2 (EN2) - a urinary marker of interest - in 90 patients with localized PC, 30 healthy controls, and 40 patients indicated for prostate biopsy. The second study evaluated 205 men with high-risk PC-features who underwent radical prostatectomy (RP) and were subject to a strict follow-up protocol of ultrasensitive PSA (UPSA) at close time intervals. The ability of particular measurements to predict biochemical recurrence (BCR) and thus the need for adjuvant therapy was assessed using the area under the curve (AUC) and a stratification model was created. The third study involved 128 patients who underwent RP. PSA and its serum isoforms normally used in the diagnostic context were evaluated both preoperatively...
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Probabilistic safety assessment of operation
Jordánová, Petra ; Mladý, Ondřej (referee) ; Kotek, Luboš (advisor)
This thesis deals with the method of modelling event trees and fault trees within the probabilistic safety assessment at the Dukovany nuclear power plant. In the first part, probabilistic safety assessment is presented, along with a description of the used analyses, specifically ETA and FTA, and the software used for development of probabilistic models at nuclear power plants in the Czech Republic. Then Large LOCA accident is described, for which a pilot model is developed in the second part of this thesis. The main aim of this thesis is a replacement of the original modelling method with a new modelling. The presented method focuses, in addition to a development of event trees and fault trees, primarily on the substitution of previously used house event for initiating events. In order to prove correctness of the created model, the cut sets from both models are compared. The benefit of the work is the elaboration of a pilot model that utilizes a different modelling method. Thanks to the presented modelling method, the existing number of event trees can be significantly reduced, and manual setting of house events can be removed. This approach simplifies the work with the model and shortens the calculation time.
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Design and Implementation of an OLAP Data Cube
Hurdálek, Pavel ; Smejkal, Milan (referee) ; Hruška, Tomáš (advisor)
This diploma thesis deals with the creation of a data OLAP cube for the purpose of analyzing big data. The process is shown when creating a cube containing data from the university's admissions process (specifically Brno University of Technology). The data is processed by the commercial tool Business Warehouse from the German company SAP, the cube visualization itself takes place in the program Excel using the Analysis extension. The result of this work is an OLAP cube, which can be used to create analyses of the university's admission procedure and obtain data to fill in the relevant section of the annual activity report.
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Neurální habituace statických reklam v homo- a heterogenním video-prostředí.
VOLCHKOV, Ivan
This bachelor thesis focuses on theoretical elaboration and empirical research of the topic of habituation and perception of static advertisements in the cyberspace during video perception. The theoretical part contains a summary of the theory and research of habituation, perception of advertisements, and visual perception, as well as the theoretical basis of electroencephalography. The empirical part describes the intention, design, implementation, results of the research and their discussion. The between-subject experimental design is constructed to mimic real cyberspace, where advertisements become noise and distractions to the Internet users. The study aims to measure the brain's habituation response to repeated advertisement presentation while viewing educational videos based on following biophysical signals (using electroencephalography), i.e., to determine how the brain learns to get used to or respond to advertising stimuli during educational video streaming and whether there is a difference in brain reaction to homo- and heterogeneous advertising stimuli. A new experimental paradigm was created for this research. 18 participants took part in the research, randomly divided into three groups: two experimental groups and one control group. 15 participants' data proceeded to the final analysis, due to technical deficiencies of signal processing. The analysis was performed using the following EEG methods: Event-Related Potentials, Event-Related Spectral Perturbation, and Power Spectral Analysis. The results indicate that homogeneous advertisements are less disruptive to the fluency of perception of the video viewer than heterogeneous ones, but may require more prominent differentiation.
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Magnetic resonance imaging of prostate and the success rates in statistics of guided biopsy of the prostate
HEFLER, Jakub
A carcinoma of a prostate is a very serious and common disease in the Czech republic and even in the whole world. It's incidence in 2018 was 62,5 in 100 000 across the Czech republic. To this day incidence and mortality slowly decreases. Diagnosis of a prostate carcinoma is started with a palpating examination per rectum. Then we determine a patient's PSA. If the PSA level is high, the patient is indicated for a biopsy od the prostate which is done with an ultrasound navigation. For more precise biopsy we use an image fusion. This means that the urologist, which is doing the biopsy, fuses an MRI image with the ultrasound. During the biopsy 10-15 samples are taken and they're histologically examined. A pathologist then determines a Gleason score of the carcinoma which takes values of 1-5 and it shows a differentiation and type of the carcinoma. Medical professionals also measure the risk of having a prostate carcinoma with PI-RADS 2.1 system. This system also has a scale of 1 to 5. A guided biopsy is usually done to patients with PI-RADS 4 or 5. For this bachelor thesis I used data from an urology department of Nemocnice České Budějovice. I took data about patients that were examined from April of 2019 to June of 2021. During that time 288 patients were examined. 45 patients that went through a MR guided biopsy were randomly chosen and their data were statistically processed. Goals of this work were: - Creating an informational text that contains anatomy and fysiology of the prostate, a mechanism of the MRI and a description on a guided biopsy of a prostate. - Determination of a statistical succes rate of an MRI guided biopsy of a prostate. Also there were hypothesis: H1: If it happens that laboratory and hystological results are not corresponding, majority of the patients are indicated for an MRI guided biopsy of the prostate. H2: At least 80% of patients have a positive result for a prostate carcinoma after an MRI navigated biopsy of a prostate. An informational text was created so the fist goal was fulfilled. Goal number 2 was fulfilled also because a statistical rate of positive and negative results of the guided biopsy were determined. This rate is 73% positive and 27% negative findings so it is necessary to reject a hypothesis H2. We can accept a hypothesis H1 according to information from MUDr. Černý that takes care of the MRI guided biopsies in Nemocnice České Budějovice.
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Prostate Cancer Diagnostic Algorithm
Sedláčková, Hana ; Hora, Milan (advisor) ; Baxa, Jan (referee) ; Záleský, Miroslav (referee)
Prostate cancer diagnostic algorithm Aim: The aim of the study is to implement the latest scientific knowledge in the diagnosis of prostate cancer (PC). We focused on tumor markers, imaging methods, prostate biopsy methodology and we created a diagnostic algorithm based on a review of current literature in combination with our own experience. Material and methods: The algorithm is divided into several branches, which have been individually subjected to clinical studies. Due to the low sensitivity and specificity of PSA, prostate health index (PHI) was added to the first line of patient stratification. 787 patients were primarily examined and these subsequently underwent radical prostatectomy. PHI levels were compared with definitive staging and grading. Cut-off values for PC detection and high-risk stratification, including locally advanced PC were determined. Next, 320 patients underwent prostate biopsy followed by radical prostatectomy. The cohort was further divided into two subgroups, patients with GS = 6 and patients with GS > 6. The ability of PHI to distinguish between insignificant and significant prostate cancer was evaluated. In a multicentric study with 395 patients, PHI with additional markers (tPSA, PSAD) and multiparametric magnetic resonance imaging of prostate (mpMRI) was assessed....
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