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Creation of a Client Database for a Financial Advisor
Holý, Vladimír ; Holá, Lucie (referee) ; Luhan, Jan (advisor)
This bachelor´s thesis deals with the formation of the database application in Microsoft Access 2003 that will serve to the financial advisors to make their communication with customers easy and faster. The contents include the formation of the proposal, charts, forms, arrangements and the visual database setting. The last part of the solution proposal deals with the important asset.
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V-pit Defects in InGaN/GaN Studied by X-ray Diffraction
Stránská Matějová, Jana ; Holý, Václav (advisor) ; Dopita, Milan (referee) ; Rafaja, David (referee)
V-pit defects in InGaN/GaN heterostructures were studied by high-resolution x-ray diffraction accompanied by numerical simulations. The work is focused on the role of the V-pits in strain relaxation, on their impact on the appearance of the x-ray reciprocal- space maps and on their relation to the threading dislocations. Analysis of the diffuse part of the diffracted intensity by kinematical scattering theory, together with principal strains and their directions in the vicinity of the V-pit, explains why the lateral position of the InGaN peak is not affected by the V-pits presence. The strain relaxation by V-pit formation was confirmed, while plastic relaxation by misfit dislocations was not observed. The density of the V-pits in the epilayer turned out to be given by the content of threading dislocation with a screw component in the substrate. Pure edge threading dislocations do not affect the V-pit density. The In concentration has an influence on the size of the V-pits, but not their density. 1
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Magnetic nanostructures with application potential
Bittová, Barbara ; Kalbáčová Vejpravová, Jana (advisor) ; Holý, Václav (referee)
The thesis is mainly focused on the investigation of macroscopic and microscopic magnetic properties of selected nanomaterials containing cobalt and iron, and also the capability of our new device, scanning probe microscope Multimode V by Veeco, to directly visualise morphology and magnetic structure of these samples (Magnetic Force Miscroscopy, MFM). Investigated materials, such as CoFe2O4 nanoparticles and SiO2_Co_Si(111) thin films and multilayers are in general promising materials in many fields. In the medicine, the nanoparticles are used as the drug targets or contrast agents whereas in electronics, the (nano)granular thin films are the starting point in fabrication of high density storage media. The macroscopic magnetic properties of our samples are discusses in a view of superparamagnetic phenomena. The interactions in systems of nanoparticles are presented theoretically within the up-to date knowledge and also experimentally by demonstrating the behavior of the strongly-interacting, uper-spin-glass system. The thin films are studied in term of their granular structure and magnetic anisotropy. The morphology and the microscopic domain structure, respectively, are studied with use of the MFM. The first successful results obtained in our lab by this method are presented.
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Diffuse x-ray scattering from GaN epitaxial layers
Barchuk, Mykhailo ; Holý, Václav (advisor) ; Caha, Ondřej (referee) ; Pietsch, Ulrich (referee)
Real structure of heteroepitaxial GaN and AlGaN layers is studied by diffuse x-ray scattering. A new developed method based on Monte Carlo simulation enabling to determine densities of threading dislocations in c-plane GaN and stacking faults in a-plane GaN is presented. The results of Monte Carlo simulations are compared with ones obtained by use of other conventional techniques. The advantages and limitations of the new method are discussed in detail. The methods accuracy is estimated as about 15%. We have shown that our method is a reliable tool for threading dislocations and stacking faults densities determination.
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X-ray investigation of defects in graded SiGe/Si thin layers
Endres, Jan ; Daniš, Stanislav (advisor) ; Holý, Václav (referee)
The goal of presented work is a study of defects in graded Si1xGex/Si thin layers. Misfit dislocations are dominant type of defects in this kind of layers. Diffuse scattering of radiation, which is caused by the presence of defects, was measured with high-resolution diffractometer. Misfit dislocations arrangement in the layers was determined from measured reciprocal space maps. Misfit dislocations distribution is discussed within the scope of two models. Equilibrium one, which is based on energy minimization, and kinetic one, which considers thermally activated movement of dislocations. Measured reciprocal space maps were compared with simulations, which were realized via kinematic theory of X-ray radiation scattering.
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Tests in multinomial distribution
Holý, Vladimír ; Anděl, Jiří (advisor) ; Antoch, Jaromír (referee)
In this paper there are at first described classical goodness-of-fit tests - the Pear- son's χ2 test and the log likehood ratio test. The more modern method of testing is the family of statistics based on power divergence which is generalisation of classical statistics. Another type of generalisation is the family of disparity statis- tics which includes beside the family of power divergence also the families BWHD and BWCS. It is demonstrated that all these test statistics have an asymptotic χ2 distribution. In the program R the exact level and exact power can be calculated for individual tests. Hereafter, moments of test statistics can be derived. On the basis of these comparisons there will be shown which test statistics are the most suitable for the goodness-of-fit tests. 1
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Theoretical studies of rolled-up and wrinkled nanomembranes
Čendula, Peter ; Holý, Václav (advisor) ; Fedorchenko, Alexander I. (referee) ; Onck, Patrick N. (referee)
Title: Theoretical studies of rolled-up and wrinkled nanomembranes Author: Mgr. Peter Cendula Department: Department of Condensed Matter Physics Thesis Supervisors: Prof. Dr. Oliver G. Schmidt, Prof. RNDr. Václav Holý, CSc. Abstract : The thesis is devoted to three similar topics from the field of rolled-up and wrinkled nanomembranes. We start by recalling classical theory of thin plates, which will be used to describe deformation of nanomembranes. In the first topic, relaxation of internal strain is studied when a flat film is partially released from the substrate by etching the sacrificial layer underneath. Energetic competition of the tube and wrinkle shape is quantitatively investigated. Similar model is used to investigate the limiting maximum value of tube rotations. In the second topic, roll-up of initially wrinkled film is shown to favor tubes forming on the flat edge of rectangular wrinkled pattern, enabling precise control of tube position. Experiment is provided to justify our theoretical predictions. In the third topic, quantum well is assumed inside a wrin- kled nanomembrane. Shift of transition energy induced by lateral modulation due to bending strain is quantified, being of interest for strain-sensitive optical detectors and emitters. In addition, lateral localization of electron and hole due to...
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