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Dimensional transmutation in quantum theory
Ebr, Jan ; Hořejší, Jiří (advisor) ; Novotný, Jiří (referee)
This work deals with two models - from the quantum eld theory it is the massless scalar electrodynamics (the so-called Coleman-Weinberg model) and from quantum mechanics it is the contact (-function) potential (in two dimensions) - that are apparently invariant under some sort of scale transformations and thus they, in suitably chosen units, contain only dimensionless parameters. It turns out that even in the quantum-mechanical case one has to add an additional procedure to the formal denition of the model and that the use of dierent physical regulators leads to the same results, that furthermore agree with the predictions of the mathematically rigorous method of self-adjoint operator extensions. In this work, we present detailed calculations supporting this result. Contrary to the common literature, we do so in a straightforward manner, which can be followed step by step (with all the necessary elements of functional analysis summarised in the Appendix). In quantum eld theory we apply a similar approach, when we "rediscover" the results of the abstract functional methods in the ordinary perturbation theory. In its framework, we further show how to obtain predictions also for other quantities than particle masses.
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Subspace Modeling of Prosodic Features for Speaker Verification
Kockmann, Marcel ; Kenny, Patrick (referee) ; Nöth, Elmar (referee) ; Černocký, Jan (advisor)
Předložená disertační práce se zabývá ověřováním mluvčího pomocí prozodických příznaků zahrnujících hodnoty základního tónu, energie a délek řečových úseků. Studovali jsme dvě rozdílné techniky pro parametrizaci: první vede k dobře definované sadě menšího počtu příznaků, druhá k vysoko-dimenzionální sadě heterogenních prozodických příznaků. První část práce se věnuje vývoji příznaků reprezentujících prozodické kontury, zde jsme vyvinuli a ověřili několik modelovacích technik, s důrazem na modelování v reprezentativních podprostorech. Druhá část práce se zaměřuje na nové pod-prostorové modelovací techniky pro heterogenní prozodické parametry s velkou dimenzionalitou. Model je teoreticky odvozen a experimentálně ověřen na oficiálních datech z NIST evaluací ověřování mluvčího (NIST Speaker Recognition Evaluation). Ve srovnání s ostatními současnými prozodickými jsme dosáhli podstatně lepších výsledků. Na konci práce presentujeme také novou techniku pro elegantní kombinaci dvou prozodických systémů. Tato technika může být použita rovněž pro fúzi prozodického systému se standardním přesným cepstrálním systémem, což vede k dalšímu podstatnému zvýšení úspěšnosti verifikace.
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Computational modelling of mechanical tests of composites "rubber - steel fibre"
Jarý, Milan ; Profant, Tomáš (referee) ; Burša, Jiří (advisor)
This diploma thesis focuses on realization of a computational model of fibre composite with elastomer matrix and on homogenization of properties of this composite. The work deals with computational modelling of strain-stress states which arise in mechanical tests of composites. The composites investigated by mechanical tests comprise of hyperelastic rubber matrix and steel reinforcing fibres. Computational modelling is carried out at two levels of the model. First, with three-dimensional modelling of fibres and matrix as two different materials and, second, using a homogenized model of composite; this constitutive model describes the composite as a homogeneous anisotropic material. It means that properties of fibres are encompassed into strain energy density by the mathematical formulation of the constitutive model. Further, the work deals with computational modelling of mechanical tests of hyperelastic isotropic materials used for identification of their material parameters and for verification of the selected constitutive model of material. For particular hyperelastic material, simulations of tests were carried out, namely of uniaxial tension, biaxial tension, uniaxial compression, biaxial compression, pure shear and uniaxial tension with constrained transversal strain (planar tension). Parameters of the constitutive model were determined of experimental input data. Verification of the constitutive model was carried out by comparison of the data acquired by experiments with the results of simulations of mechanical tests in FE program system Ansys. Then the authentic constitutive model of material was used for description of matrix behaviour in models of mechanical tests of composite material and results were compared with experimental data. Principal objectives which I want to attain are following: • to acquaint with the constitutive models of hyperelastic isotropic and anisotropic materials and identification of their perameters on base of mechanical tests. • to create computational models of testing specimens of composite “ rubber – steel fibre“ for different fibre arrangements and to use the created computational models in simulations of chosen tests. • to test the possibilities of computational modelling of composites with application of homogenized properties and to compare the results of both approaches. Results which were attained: • the computational models were created with the fibres modelled; the strain – stress characteristics are qualitatively corresponding to experiments, and quantitative difference is 20% - 40% (see (4.3)). • the computational models based on homogenization of properties were tested and gave results corresponding to the models with modelled fibres (see (4.4)) with a good accuracy.
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Recognition of picture languages
Barták, Jakub ; Plátek, Martin (referee) ; Mráz, František (advisor)
We present a transformation of one-dimensional shrinking restarting automaton concept into two-dimensions. The resulting automaton (called Two-dimensional Restarting Automaton - 2RA) proved to have an interesting closure properties as well as close relation to the class or recognizable languages (REC) which qualify it as a notable member of two-dimensional language hierarchy.
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Programmable illuminating system for an optical microscope
Lošťák, Martin ; Křupka, Ivan (referee) ; Chmelík, Radim (advisor)
A programmable illuminating system (PIS) uses a commercial multimedia projector together with a suitable optical relay system in order to illuminate specimens under microscope with transmitted light. The theoretical part of the diploma thesis describes some methods used in the optical transmission microscopy. All of these methods employ physical masks placed in the condenser front focal plane. In the case of the traditional methods the masks are used to enhance contrast (e.g. dark-field illumination) and resolution (oblique illumination). One of the methods (a condenser with rotating aperture) provides the information about the three-dimensionality of the specimen. The next part of the thesis contains the theory and the basic classification of the illuminating systems used in the optical transmission microscopy. An optical and mechanical design of the optical relay system used for PIS is introduced. The experimental part shows the results made with two different PIS arrangements. It was shown on two different specimens that the PIS provides the same illumination as the classical methods. It was also proved that the PIS can simulate the rotating aperture in the condenser front focal plane and thus to give the information about the three-dimensionality of the specimen. Some new static and dynamic illuminating methods were introduced.
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Combining OLAP and data mining for analysis on trainee dataset
Borokshinova, Anastasia ; Chudán, David (advisor) ; Šimůnek, Milan (referee)
The aim of this thesis is to show the possibility of combining two data analyses techniques OLAP and data mining in a certain area. The principal method of achieving the aim will be continuous comparison and check of acquired results using two techniques. A practise dataset on credits provided to physical persons is used for practical application. The data analysis will be performed using Power Pivot MS Excel complement and LISp-Miner system. For work with LISp-System the 4ft Miner procedure will specifically be used, which proceeds according to respected CRISP-DM data mining methodology. The thesis added value consists first of all in presentation of a possibility of OLAP and data mining linkage on the same dataset, thus reducing the number of erroneous conclusions which analysers might arrive at on the basis of one technique. Other benefits consist in presentation of relational data transfer to multi-dimensional structure and practical options of 4ft-Miner system LISp-Miner procedure usage.
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FEMM program - preparation of education materials
Pešek, Michal ; Huzlík, Rostislav (referee) ; Vítek, Ondřej (advisor)
The manual is supposed to introduce to users the program FEMM. It is designed for solving low freqency electromagnetics problems. It shoul allow students, who are not experienced with work in english interface programs, make a model and set parametres needed for successful solution of required problem. There is description of setting and location of important program elements. Users have to quickly understand, how to work in program. FEMM work indeed in two dimensional mode and it is simplier, than expensive 3D programs, on the other hand, he is free for commercial and noncommercial use. It makes this program very interesting for home using by students. Licence restricton is related with program code itself and selling only.
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Self-service BI for retail industry
Čoček, František ; Pour, Jan (advisor) ; Šedivá, Zuzana (referee)
This thesis addresses current topic of self-service business intelligence solutions. The main goal is to create a dimensional model and pilot applications for retail used for Management of Business Informatics (MBI). In order to achieve it is main goal there are four steps, to be taken. During fulfilling of these steps minor and practical goals are achieved as well. Minor goal focuses on comparison of the advantages and disadvantages of current business intel-ligence approaches. Practical goal is to create reports and dashboards for Management of Business Informatics (MBI). The first step is to introduce the issue of classic and self-service BI concluded by comparison of both variants. The second step is the definition of retail and identification of potential indicators. The third step is the introduction of Mi-crosoft´s self-service BI technologies and tools. The fourth step is to create applications for retail in MBI using tools PowerPivot and Power View. The main contribution of this work is to create reports and dashboards that are able to support processes of general retail mod-el. Reports and dashboards will serve as pilot applications for MBI. Another contribution is to acquaint readers with the possibilities of tools PowerPivot and Power View.
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