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Statistical Expectation of High Energy Physics Data Sets Separation Algorithms
Hakl, František
Article focuses on the application of the basic results of the statistical learning theory known as Probabilistic Approximately Correct learning in the evaluation and post-processing of unique physical data obtained from the detectors of particle accelerators. The aim of this article is not direct separation of the measured data but evaluation of the appropriateness of separation methods used. The main principles and results of the PAC learning theory are briefly summarized, the main characteristics of selected multivariable data separation algorithms are studied from the VC-dimension point of view. Finally, based on actual data sets obtained from Tevatron D$\emptyset$ experiment, some practical hints for separation method selection and numerical computation are derived.
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Integrated Education of a Pupil with Special educational needs - Case Study
Habartová, Iva ; Mrkosová, Eva (advisor) ; Ptáčková, Klára (referee)
The aim of this thesis is to analyse the current situation in integrated educating of a pupil with special educational needs, or more specifically, of a child with high functioning autism combined with practical deafness. Through analysis of specialised literature, the theoretical part defines the expression integration; other definitions include hearing disability and autism as the causes limiting the pupil's inclusion in educating in a mainstream elementary school. The practical part of the thesis includes a case study - description of the pupil's case. Experience is described from the current integrated education in a special elementary school where the pupil is educated according to the Framework Educational Program for Elementary Schools, with the prospective of upcoming re-integration into the mainstream elementary school, or, as the case may be, depending on the parents' decision, his integration in an elementary school for hearing impaired children. In drawing up the case study, the following methods were applied: observation and analysis of the pupil's educational products.
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Changes in structure and phase composition in the surface of tram rail
Švábenská, Eva ; Roupcová, Pavla ; Schneeweiss, Oldřich
We have investigated structure and phase composition of surface layer of tram rails after long time running and the results were compared with those obtained on the original part of material. Changes due to effects of severe plastic deformation together with thermal shocks by friction process were expected. The information about structure and phase composition was obtained by optical and scanning electron microscopy, X-Ray Powder Diffraction, Mössbauer Spectroscopy and Glow Discharge Emission Spectroscopy (GDOES) and this was completed by microhardness measurements. The results show that the surface layer in comparison with the original material exhibits important changes in grain structure, an increase in microhardness and high content of iron oxide and hydrooxides. According to the depth profile of the chemical composition measured by GDOES there is an increase in carbon content in the surface layer which can be effect of up-hill diffusion.
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A Comparison of Preconditioning Methods for Saddle Point Problems with an Application to Porous Media Flow Problems
Axelsson, Owe ; Blaheta, Radim ; Hasal, Martin
The paper overviews and compares some block preconditioners for the solution of saddle point systems, especially systems arising from the Brinkman model of porous media flow. The considered preconditioners involve different Schur complements as inverse free Schur complement in HSS (Hermitian - Skew Hermitian Splitting preconditioner), Schur complement to the velocity matrix and finally Schur complement to a regularization block in the augmented matrix preconditioner. The inverses appearing in most of the considered Schur complements are approximated by simple sparse approximation techniques as element-by-element and Frobenius norm minimization approaches. A special interest is devoted to problems involving various Darcy, Stokes and Brinkman flow regions, the efficiency of preconditioners in this case is demonstrated by some numerical experiments.
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STRAIN ENGINEERING OF THE ELECTRONIC STRUCTURE OF 2D MATERIALS
del Corro, Elena ; Peňa-Alvarez, M. ; Morales-García, A. ; Bouša, Milan ; Řáhová, Jaroslava ; Kavan, Ladislav ; Kalbáč, Martin ; Frank, Otakar
The research on graphene has attracted much attention since its first successful preparation in 2004. It possesses many unique properties, such as an extreme stiffness and strength, high electron mobility, ballistic transport even at room temperature, superior thermal conductivity and many others. The affection for graphene was followed swiftly by a keen interest in other two dimensional materials like transition metal dichalcogenides. As has been predicted and in part proven experimentally, the electronic properties of these materials can be modified by various means. The most common ones include covalent or non-covalent chemistry, electrochemical, gate or atomic doping, or quantum confinement. None of these methods has proven universal enough in terms of the devices' characteristics or scalability. However, another approach is known mechanical strain/stress, but experiments in that direction are scarce, in spite of their high promises.\nThe primary challenge consists in the understanding of the mechanical properties of 2D materials and in the ability to quantify the lattice deformation. Several techniques can be then used to apply strain to the specimens and thus to induce changes in their electronic structure. We will review their basic concepts and some of the examples so far documented experimentally and/or theoretically.
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ELECTRON BEAM REMELTING OF PLASMA SPRAYED ALUMINA COATINGS
Matějíček, Jiří ; Veverka, J. ; Čížek, J. ; Kouřil, J.
Plasma sprayed alumina coatings find numerous applications in various fields, where they enhance the properties of the base material. Examples include thermal barriers, wear resistance, electrical insulation, and diffusion and corrosion barriers. A typical structure of plasma sprayed coatings, containing a multitude of voids and imperfectly bonded interfaces, gives them unique properties - particularly low thermal conductivity, high strain tolerance, etc. However, for certain applications such as permeation barriers or wear resistance, these voids may be detrimental.\nThis paper reports on the first experiments with remelting of plasma sprayed alumina coatings by electron beam technology, with the purpose of densifying the coatings and thereby eliminating the voids. Throughout the study, several parameters of the e-beam device were varied - beam current, traverse velocity and number of passes. The treated coatings were observed by light and electron microscopy and the thickness, structure and surface morphology of the remelted layer were determined and correlated with the process parameters. Based on the first series of experiments, the e-beam settings leading to dense and smooth remelted layer of sufficient thickness were obtained. In this layer, a change of phase composition and a marked increase in hardness were observed.\n
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Nutrition and other factors, which have influence on the formation and prevention of colorectal cancer
BENEŠOVÁ, Lucie
The full title of my bachelor thesis is Nutrition and Other Factors Influencing the Development and Prevention of Colorectal Cancer. In the theory section of the paper I have concentrated on clarifying the term "colorectal cancer", its epidemiology, and furthermore, on diet and other risk factors concerning the development and prevention of this disease. In this theory section I have included information about screening tests for occult bleeding. I have addressed the key objectives in the practical section of the thesis. I had set two key objectives. The first was to research how well respondents were informed concerning diets beneficial in the prevention of colorectal cancer, and the second objective concentrated on assessing the respondents' behaviour in relation to the information they had acquired. The research questions were formulated thus: "How well are people informed about diets aimed at preventing colorectal cancer?" and "Do people behave according to information thus gained?" The qualitative research method a semi-structured interview was used for the research section. Ten male respondents over the age of 45 took part in the interview. Five of these males were Dr Ilona Paseková's outpatients all with a genetic disposition to colorectal cancer, with most experiencing problems related to this disease. The other five respondents were without any predispositions. After receiving answers to the questions posed to the respondents, I wanted to compare both groups in order to ascertain whether those with a genetic predisposition showed a greater interest in this disease. Furthermore, I wanted to find out whether those respondents were actively seeking information concerning the prevention or treatment of colorectal and anal cancer. All those interviewed were very open and willing to answer questions. Collection of data was carried out from January 2014 to March 2014. The conclusions of this thesis show that public awareness of colorectal cancer and its prevention is inadequate. Public awareness of diets beneficial in the prevention of colorectal cancer is markedly poor, even among high-risk respondents. Having observed this lack of awareness, I proceeded to question respondents as to their dietary and lifestyle habits. Furthermore, the respondents were asked if they were aware that colorectal cancer screening was available in the Czech Republic. The results showed that some respondents, however unaware of diets beneficial in the prevention of colorectal cancer, follow a healthy diet, thus fulfilling dieticians' recommendations concerning the prevention of this disease. When asked about preventive foods, respondents most often mentioned brassicas broccoli and cabbage, etc. Conversely, the most often mentioned foods said to increase the risk of disease were smoked meat and red meat. One respondent mentioned the preventive affects of shark cartilage. I was very surprised by this assertion and subsequently searched the internet for information relating to shark cartilage. To my surprise, I found that the respondent was indeed not mistaken, and that statements to that effect can be found on websites promoting dietary supplements containing shark cartilage extract. According to these sources sharks do not suffer from cancer and therefore, their cartilage is closely studied and dietary supplements containing its extracts are produced. Furthermore, I intended to compare two groups of respondents those with genetic dispositions and those without. After carrying out the respective interviews, their comparison appeared to be futile. In both groups I identified respondents who followed a healthy diet and lifestyle as well as those who did not. I found that there is no relation between high-risk habits and predisposition to colorectal cancer. Whether a respondent with such a predisposition decided to follow a healthy diet or change his dietary habits and lifestyle or not was purely a question of his personal preferences.
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The use of biomass ash
Ochecová, Pavla ; Tlustoš, Pavel (advisor) ; Radim, Radim (referee)
One of the most frequently used sources of renewable energy is biomass, mainly wood biomass. Incineration is the most common technology utilizing the energy from biomass to produce heat. A byproduct of these technologies is ash, whose composition depends on the feedstock composition and the incineration technologies. Due to the high content of valuable nutrients in ash, one of the suitable option for ash utilization seems to be application into agricultural or forestry land. Therefore, it is necessary to test response of soils and plants and look for the most suitable combination of soil additive (biomass ash), and plants. Experimental part of PhD thesis was divided into the incubation experiment and the vegetation pot experiments. The incubation experiment: The efficiency of ash addition at two application rates was tested for nutrients enrichment in different soils within period of 56 days. The vegetation pot experiments: The two plants Triticum aestivum L: (three-year experiment) and Lolium perenne L. (one-year experiment) were planted in the 5L pots. Soils were treated with ash or ash combinated by superphoshate and flue gas desulfurization gypsum. For both plants, we evaluated the plant growth, biomass production and content of macro, micro and toxic elements in the biomass and in the soils.
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Single particle analysis of size-segregated aerosol in Prague city center
Marvanová, S. ; Skoupý, Radim ; Kulich, P. ; Bendl, J. ; Hovorka, J. ; Machala, M.
Particulate matter (PM) is omnipresent pollutant in the ambient air known to cause cardiovascular and respiratory diseases (WHO 2004). Recently, outdoor air pollution and particulate matter in outdoor air pollution were classified as carcinogenic to humans, Group 1 (IARC 2015). Especially, ambient PM of aerodynamic diameter < 100 nm, ultrafine particles, appears to be of great importance due to its high specific surface area and high number concentration (Hughes et al. 1998). Ultrafine particles also easily enter and are being transferred in organisms, and interact with cells and subcellular components (Oberdorster et al. 2005). As the evidence of ultrafine PM significance increased, size-fractionated PMs sampled by various cascade impactors have been employed into the toxicological studies on cell cultures or isolated cells, using the organic extracts of size-fractionated PMs (Topinka et al. 2013, Topinka et al. 2015) or directly the size-fractionated particles (Becker et al. 2003, Ramgolam et al. 2009, Reibman et al. 2002, Loxham et al. 2013, Jalava et al. 2006, Thomson et al. 2015, Jalava et al. 2015). The aim of this study was to evaluate shape and composition of size-segregated aerosol particles, sampled by high volume cascade impactor, using electron microscopy and energy dispersive X-ray spectroscopy (EDX).
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Radio frequency resonator for feeding ion trap
Jedlička, Petr ; Pham, Minh Tuan ; Čížek, Martin ; Pavelka, Jan ; Lešundák, Adam ; Hucl, Václav ; Hrabina, Jan ; Řeřucha, Šimon ; Lazar, Josef ; Číp, Ondřej
Two versions of resonators were designed and manufactured - asymmetric and symmetric.\nThe resonator consists of a coil and capacity of ion trap which makes parallel resonant circuit.\nEnergy is supplied to the resonator through the coupling inductance. Resonator assembly was equipped with outputs for monitoring high-frequency voltage. Both versions have been tuned and tested.\n\n
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