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Source localization for EEG patterns relevant to motor imagery BCI control
Bobrov, P. ; Frolov, A. ; Húsek, Dušan ; Tintěra, J.
This work concerns spatial localization of sources of EEG patterns the most specific for control of the motor imagery based BCI. In our previous work we have shown that performance of Bayesian BCI classifier can be drastically improved by extraction of the most relevant independent components of the EEG signal. This paper presents the results of spatial localization of electrical brain activity sources which activity is reflected by the extracted components. The localization was performed by solving the inverse problem in EEG source localization, using individual finite-element head models. The sources were located in central sulcus (Brodmann area 3a), in the superior regions of post- and precentral gyri, and supplementary motor cortex.
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INFLUENCE OF LASER CUTTING AND PUNCHING ON MAGNETIC PROPERTIES\nOF ELECTRICAL STEEL M470-50A
Bulín, Tomáš ; Švábenská, Eva ; Hapla, Miroslav ; Ondrůšek, Č. ; Schneeweiss, Oldřich
Electrical steel M470-50A belongs to the most often used materials in electrical machines. Due to this fact, it is desirable to know the magnetic parameters after processing raw sheets into the required shape. Basic parameters of mechanical, electrical, and magnetic properties of the sheets are usually obtained from the producer but the magnetic properties are changing in dependence on additional machining processes. The aim of this study is to describe changes in parameters of magnetic behavior after punching, laser and spark cutting of the original sheets. The basic information of structure was obtained by optical and scanning electron microscopy. The magnetic parameters were acquired from the measuring of magnetic hysteresis loops in dependence on saturation fields and frequencies. The results are discussed from the point of view of applied\ncutting technology with the aim to obtain the best magnetic parameters and consequently a higher efficiency of the final product. Results can be used as input parameters in simulation of the electrical machine.
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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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Satisfaction of women in labour with nursing care during childbirth.
KLÍMOVÁ, Magdaléna
This dissertation investigates the level of satisfaction among expectant mothers with the care services provided during childbirth. Satisfaction reflects a subjective perception of an expectant mother in meeting her needs during childbirth. The feeling of satisfaction is very personal, however, evaluation of the care provided needs to be determined and not ignored. It is important for expectant mothers that the health care professionals present as empathic, friendly, co-operative, and tactful.Theoretical part was developed from evidence-based literature and available findings related to this problematic. There is a description of a childbirth process including a midwife's role during the individual stages of childbirth and options for pain management. Other chapters focus on midwife's approach toward an expectant mother and factors which influence the level of satisfaction during childbirth. Dissertation's aim was to determine whether the expectant mothers were more satisfied in smaller maternity departments, and to evaluate the way a midwife may influence the mother's satisfaction. There were two hypotheses stated and verified by a statistical testing. Hypothesis No. 1: Expectant mothers are more satisfied in smaller maternity departments than larger ones. Hypothesis No. 2: The level of satisfaction is influenced by midwife's empathic approach. Practical part focused mainly on a midwife's approach toward expectant mother. A quantitative research was implemented in form of questionnaires. The research sample constituted of expectant mothers from four postpartum departments in the Czech Republic. In total the sample included 215 expectant mothers, 109 from smaller facilities and 106 from larger maternity departments. In terms of the overall level of satisfaction with their midwife during the childbirth process, 89% of expectant mothers from smaller maternity departments and 83% of expectant mothers from larger departments stated they were satisfied. Conversely, 11% of respondents from smaller facilities and 17% of respondents from larger facilities were dissatisfied. Based on research analysis comparing the level of satisfaction of expectant mothers from smaller and larger maternity departments the hypothesis no. 1 "Expectant mothers are more satisfied in smaller maternity departments than the larger ones" did not show as statistically significant and was rejected. Nonetheless, the questionnaire responses clearly showed that empathic approach of a midwife influenced expectant mother's satisfaction. Statistical testing demonstrated a significant correlation between an expectant mother's satisfaction and empathic approach of a midwife. The second hypothesis "The level of satisfaction is influenced by midwife's empathic approach" was accepted.The research findings may serve as a guiding material for the midwives in order to provide a high quality care to expectant mothers during the childbirth process. They may also be utilised by future midwives who are in undergraduate preparation for the profession, or those professionals who contribute in any way during the childbirth process. Additionally, the research findings may be presented at conferences designated for midwives.
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The Liberation of Pilsen 1945 in Photography
Křenová, Tereza ; SILVERIO, Robert (advisor) ; JANOŠČÍK, Václav (referee)
This bachelor thesis deals with liberation of Pilsen in May 1945 by american army in photography. The aim of this thesis is finding and collecting archival materials and placing them in a historical-political context. Communist regime changed the portrayal of historical events and directly influenced the amount of exisiting photographs, documents and lives of those who created them. Important part of this bachelor thesis is working with those archival materials – particularly with photographs capturing arrival of Americans and their stay in Czechoslovakia at the end of WW2. Both professional and amateur photographers created valuable photographs as they witnessed the liberation of Pilsen. These photographs became in spite of communist propaganda a clear evidence that Pilsen was liberated by american army.
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Sorption and Stabilization of Metals/Mettalloids by Innovative Synthesized Sorbent Amochar.
Ouředníček, P. ; Trakal, L. ; Komárek, M. ; Pohořelý, Michael
Remediation of contaminated soil which is based on stabilization and immobilization of potential\nhazardous substance by sorption materials has been studied intensively nowadays. Biochar – activated organic carbon belongs to this group of stabilizing agents which can adsorb wide range of contaminants, including metals/metalloids. Surface area of the biochars is quite large in general and functional groups (e.g. COO–) can form chelates or alkaline elements on the surface, which is represented by cation exchange capacity. Altogether with the high pH values (7.00 – 10.00), biochars are quite effective sorbents and can adsorb metals/metalloids from the solution (ground water), especially in acidic soils (in the environments affected by intensive mining activities). Sorption\neffectiveness can be increased (especially for As (V) or Cr (VI) sorption) by modification of biochar by various types of secondary oxides. Innovative sorbent AMOchar (AMO + biochar) has been synthesized currently. The product was prepared by adding of biochar to the reaction solution during amorphous manganese oxide (AMO) synthesis. The AMOchar was formed mainly by Mn-oxalates which had coated surface of the pristine biochar. AMOchar composite was able to remove significantly higher amounts of various metal(loid)s from the solution despite the rather high pH of the material. Sorption effectiveness was high not only in case of Pb (II) sorption (almost 99%), and Cd(II) (51.2%), but also a very high amount of As(V), 91.4%. Additionally, both AMOchar composite was able to reduce Mn leaching. This can avoid potential post-contamination caused by the dissolution of less stable Mn-oxalates as observed in the pure AMO.
Fulltext: content.csg -  PDF
Plný tet: SKMBT_22316111113040 - PDF
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