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Algorithm of imaging methods in suspicion on pulmonary tuberculosis
MIKULÁŠOVÁ, Jana
Tuberculosis is an infectious disease which more than 8 million people are taken ill with throughout the world every year. During the last decade more than 30 million people succumbed to it. The Czech Republic succeeds in decreasing the number of TB cases, despite of it the physicians warn how dangerous is still this infectious disease. Basic diagnostic examination in pulmonary TB is an X-ray examination. Radiophotography, so called {\clqq}štítovka`` enacted remarkable part in combating TB. This apparatus was used in past for collective X-ray examination. The disadvantage of this technique is substantionally higher radiation load. In my work I dealt mostly with contemporary possibilities of radiodiagnostics in pulmonary TB examination (with regard to radiophotography). I carried out measurement of entering surface kerma with the help of water phantom in different work places, with different types of machines. In my thesis I compared examination techniques, both from the point of diagnostic yield , and from the point of patients´ radiation load. X-ray diagnostics participates in big rate in medical irradiation, which is the most important part in human irradiation from artificial radiation sources. Implementation of new diagnostic methods (especially computer tomography) resulted in important expansion of diagnostic possibilities . On the other hand, historical equipment still functions, e.g. cabin machines for imaging from the photographic plate. The most important factors affecting radiation load of patients is modern machine equipment, regular running of tests of long-term stableness and working steadiness , as well as protective aids use. In every work place with sources of ionizing radiation a permanent supervision on respecting of radiation protection rules must be ensured.
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Minimum Weight Triangulation (MWT)
Charvát, Pavel ; Kolingerová, Ivana (advisor) ; Ferko, Andrej (referee)
For a long time, it has been neither known whether MWT is solvable in a polynomial time nor whether it belongs to NP. As we now, its status still remain unknown. We present severalknown approaches to MWT such as modifications of the problem with known time complexity or various heuristics and approximations which allow us to find an exact or at least an approximate solution in a reasonable time. We compare the approximations in some particular situations. The main part of the work is devoted to a description and implementation of an efficient heuristic with (almost?) linear expected complexity for points uniformly distributed in some convex shape. The algorithm is a modification of Drysdale's algorithm for finding GT candidates and Beurouti's computation of the modified LMT-skeleton, where we add some proofs of the correctness. We are able to complete MWT from the graph of candidate edges in O(n · d3 + n · d2+k), where d is the the maximum degree and k is the maximum number of inner components of some skeleton face. Further, we suggest a new approximation of MWT with polynomial complexity in the worst case and (almost?) linear expected complexity, which only rarely differs from the optimal triangulation and has O(1) approximation factor in the worst case. This approximation combines the LMT-skeleton...
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Algorithm for Calculation of Radiation View Factors
Bílek, Tomáš ; Hlavička, Rudolf (referee) ; Čermák, Libor (advisor)
This thesis deals with a calculation of radiation view factors. The thesis includes mathematical model of the problem and its numerical solution. The main aim of the thesis is the creation of an algorithm for calculation of radiation view factors for given 3D geometries and its application for the heat flux analysis. CAD models of geometries, specified by a NASTRAN file format, are used as an input of the algorithm. Matrix of radiation view factors serves then as an output of the algorithm. The algorithm is programmed in MATLAB, but STAR-CCM+ is used for the NASTRAN specification of separate models. The algorithm is also designed for a computation on a computer cluster for cases of intricate geometries with consideration of shading areas.
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Selection of suitable fluid flow directions in laminar flow tubular cooler
Krobot, David ; Kohoutek, Josef (referee) ; Jegla, Zdeněk (advisor)
This master’s thesis is devoted to problematic of selection of suitable flow directions in double pipe heat exchanger. First chapter is oriented to the construction of tube heat exchangers. It is also discussed impact of construction solution to the flow character and changing of his process parameters. The difference between parallel and countercurrent flow is also occurred in this parts. The next chapter is focused to the basics of heat-hydraulic calculations of heat exchanger. This also means explanation of ways of heat transfer and heat exchanger function. There are told about specific access to the solving problem of fluid laminar flow. The third chapter is detailed focused to the calculating of heat exchanger. At first is discussed factors, which have impact to the flow character. Next are detailed descriptions of design and controlling calculations, including more alternative ways to solve it. Next chapter exploit those results for deciding, which flow arrangement will be better for given case. Last chapter contain realization and reformulating of process heat exchanger calculating to the program code in Maple. There is also description of used algorithms and operating with them, so any user could be able to work with it. In this master’s thesis are used many examples from attached programs on different parts.
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Optimization of Gaussian Mixture Subspace Models and Related Scoring Algorithms in Speaker Verification
Glembek, Ondřej ; Brummer, Niko (referee) ; Campbell,, William (referee) ; Burget, Lukáš (advisor)
Tato práce pojednává o modelování v podprostoru parametrů směsí gaussovských rozložení pro rozpoznávání mluvčího. Práce se skládá ze tří částí. První část je věnována skórovacím metodám při použití sdružené faktorové analýzy k modelování mluvčího. Studované metody se liší převážně v tom, jak se vypořádávají s variabilitou kanálu testovacích nahrávek. Metody jsou prezentovány v souvislosti s obecnou formou funkce pravděpodobnosti pro sdruženou faktorovou analýzu a porovnány jak z hlediska přesnosti, tak i z hlediska rychlosti. Je zde prokázáno, že použití lineární aproximace pravděpodobnostní funkce dává výsledky srovnatelné se standardním vyhodnocením pravděpodobnosti při dramatickém zjednodušení matematického zápisu a tím i zvýšení rychlosti vyhodnocování. Druhá část pojednává o extrakci tzv. i-vektorů, tedy nízkodimenzionálních reprezentací nahrávek. Práce prezentuje dva přístupy ke zjednodušení extrakce. Motivací pro tuto část bylo jednak urychlení extrakce i-vektorů, jednak nasazení této úspěšné techniky na jednoduchá zařízení typu mobilní telefon, a také matematické zjednodušení umožněňující využití numerických optimalizačních metod pro diskriminativní trénování. Výsledky ukazují, že na dlouhých nahrávkách je zrychlení vykoupeno poklesem úspěšnosti rozpoznávání, avšak na krátkých nahrávkách, kde je úspěšnost rozpoznávání nízká, se rozdíly úspěšnosti stírají. Třetí část se zabývá diskriminativním trénováním v oblasti rozpoznávání mluvčího. Jsou zde shrnuty poznatky z předchozích prací zabývajících se touto problematikou. Kapitola navazuje na poznatky z předchozích dvou částí a pojednává o diskriminativním trénování parametrů extraktoru i-vektorů. Výsledky ukazují, že při klasickém trénování extraktoru a následném diskriminatviním přetrénování tyto metody zvyšují úspěšnost.
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Security of social networks
Hric, Michal ; Veber, Jaromír (advisor) ; Luc, Ladislav (referee)
Social networks represent an integral part of the personal, and in some cases, professional life of many people. The security of social networks is one of the key factors that determines its quality and credibility. The thesis analyzes security of six of most widely used social networks, with emphasis on the security of their web applications, optional security features of user accounts and privacy policies. Web application security was different for all investigated social networks. The most common deficiency was the use of SHA-1 signature algorithm, RC4 cipher support and unsupported option HSTS. Optional security features of user accounts were managed best by the first two evaluated networks (Facebook and YouTube), while other social networks provided less optional security features. Privacy policies didn't differ significantly, major differences were determinated by social network functionality. Although there are known risks related to insufficient security of social networks, even the most widely used social networks have deficiencies in this area.
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SEO in terms of redesign and organic search
Brůnová, Kateřina ; Benda, Petr (advisor) ; Monika , Monika (referee)
This thesis deals with the decline in decrease of traffic to the website at their redesign or significant intervention into their content, in terms of optimizing websites for search engines. This issue is known acronym for SEO - Search Engine Optimization.
The search part focuses on the functioning of the search engine algorithms, factors affecting traffic to sites and their success in the search results. It also describes the appropriate procedures for the planned redesign, a significant interference with the content of sites that always leads to a decrease traffic from organic search. These procedures should eliminate a decrease in traffic to a minimum.
The practical part shows the functionality of the procedures described in the theoretical part of the work on real cases of websites of various sectors and the difficulties of those sites that have ignored these recommendations or not incorporated them correctly.
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SEO analysis of the selected site
Hošták, Miroslav ; Sova, Martin (advisor) ; Böhmová, Lucie (referee)
The bachelor thesis is dealing with problematic of website optimization for search engines. The result of the thesis is a creation of a control list that includes SEO factors that would be possible to use for controlling optimization of a smaller websites that are utilised for presentation purposes of tradesmen and small enterprises or alternatively, proceed accordingly to that when optimizing. Thesis is divided into theoretical and practical part, theoretical part includes first to third chapters and practical fourth and fifth. First chapter is dealing with SEO characteristics based on multiple opinion routings, describes division of SEO techniques into ethical and unethical, comments overall significance and addition of SEO, deals with its history and describes its relationship with online marketing. Second chapter is focused on present state of SEO, deals with relevant trends of website development and describes their mutual influence with algorithms of search engines, mostly Google search engine and sketches a prognosis of future direction of SEO. Third chapter adds information about web searching, specifically discusses characteristics and division of various types of search engines, describes what factors influences indexing ability of web sites and focuses in detail on Google search engine, characterises it and explains its underlying principles. First chapter of practical part of the thesis -- fourth, directly deals with creation of controlling list that serves for SEO optimisation of web sites. Describes reasons and a mode, by which was this list compelled and explains and advocates enlistment of its specific parts -- SEO factors. Further on, deals with division, quality and weights of specific factors. Fifth chapter deals with practical application of a control list on a specific example of a selected web site. Includes a description of a selected web site and results of an analysis conducted on it. Explains inclusion of selected SEO factors into a revitalisation of a web site and rates their success. Conclusion of work is related to assessment of overall value addition of a control list, of which significance and effectivity is supported by included practical findings.
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