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  • About
  • The Global ETD Search service is a free service for researchers to find electronic theses and dissertations. This service is provided by the Networked Digital Library of Theses and Dissertations.
    Our metadata is collected from universities around the world. If you manage a university/consortium/country archive and want to be added, details can be found on the NDLTD website.
221

Instalace malé větrné elektrárny / Installation of small wind power station

Puchnar, Jiří January 2015 (has links)
This work is focused on the power engineering of the Czech Republic, particularly the alternative and its subset, wind power. Introduction acquaints readers with the state of energy in the country. They're the facts of the historical development of energy in Czechoslovakia and its status today. Representation of particular sources which are involved in the so-called. "Big Energy", their description and production. Each of the resources used is briefly described and discussed basic advantages and disadvantages arising from the nature of the source. It is also outlined the possible development of energy and change in the application of these resources in the future. The conclusion is devoted to alternative energy sources. Strives to cover the positive and negative aspects. It also shows the effect of alternative energy sources to power grid stability. The conclusion of this chapter is devoted to draft measures to increase the use of alternative energy sources in the energy mix of the Czech Republic. The second part is devoted to experimental measurements on small wind turbine JPT-100 from Jetpro Technology, Inc. The beginning describes the basic mathematical methods for calculating wind power and wind turbine itself. The text is accompanied by illustrative graphs. Another part deals with the actual wind turbine JPT-100. There are mentioned its characteristics, complete description of measuring workplace and measurement results.
222

Lávka pro pěší podporovaná kabely / Cable-supported pedestrian bridge

Hlava, Martin January 2015 (has links)
The purpose of the master’s thesis is about a concept of a pedestrian bridge´s bearing construction for pedestrian endorsed wires above a highway R35. The work includes a statical construction calculation of the suspended foot bridge of six spans, which has been chosen from three options. The chosen option is built of a monolithic, pre-stressed concrete board supported by suspenders, which is made by segmental elements above the fast highway. Calculation of a longitudinal direction has been made in an ANSYS application. Assembling status and cross direction of the construction has been modelled at SCIA Engineer. The construction´s recognition has been made manually expect of several towers cross-section, where the judgement has been made at IDEA StatiCa.
223

Návrh sanace sesuvu / Design of Landslide Remediation

Poruba, Michal January 2015 (has links)
Main goal of thesis entitled "Landslide remediation design" is - based on acquired knowledge and submitted documents about the problematic of landslides - to determine the causes of the landslides on II. class road between villages Koryčany and Jestřabice and to propose optimal redevelopment.
224

Detekce těžkých kovů v kapalinách metodou spektrometrie laserem buzeného plazmatu / Detection of heavy metals in liquids employing laser-induced breakdown spectroscopy

Skočovská, Katarína January 2015 (has links)
The diploma thesis deals with the use of laser induced breakdown spectroscopy (LIBS) for detection of heavy metals traces, copper and lead, in aqueous solution of copper(II) sulphate pentahydrate and lead(II) ethanoate trihydrate. Results obtained by using single and double-pulse LIBS are compared. The theoretical section focuses on the issue of heavy metals and detection possibilities, describes the fundamental principle of LIBS technique and its modification for liquid analysis. The experimental section describes analyzed samples, the experimental apparatus, double-pulse technique, and method of spectral analysis. The moving breakdown model, which theoretically predicts optimal values of some experimental parameters, is explained briefly in section Optimalizácia. This model has been tested, however the results of experiments did not prove the theory. Furthermore, the experimental section reports the process and results of the optimization of all key measurement parameters and obtaining limits of detection from calibration curves.
225

Lávka pro pěší přes řeku Berounku / Footbridge over the Berounka river

Pejčoch, Karel January 2017 (has links)
THE OBJECT OF THE MASTER THESIS IS TO DESIGN OF SUPPORTING STRUCTURE OF PEDESTRIAN BRIDGE SITUATED OVER THE RIVER OF BEROUNKA. THE THESIS CONTAINS STATIC ANALYSIS OF THE CABLE-STAYED BRIDGE WITH TWO FIELDS, WHICH WAS CALCULATED IN THREE VERSIONS .THE CHOSEN VERSION OF THE BRIDGE CONSIST OF MONOLITIC AND PRECAST CONCRETE BRIDGE DECK, WHICH IS CONSTRAINED USING PRESTRESSED CABELS AND SUPPORTED BY HANGINGS.THE CALCULATIONS OF THE LONGITUDINAL WAS PERFORMED BY COMPUTATIONAL SOFTWARE OF SCIA ENGINEERING 15.1
226

Kmenové buňky zubní pulpy / Dental pulp stem cells

Suchánek, Jakub January 2011 (has links)
The aim of this dissertation study was to optimize the isolation and long term cultivation protocols for human dental pulp stem cells. The protocols which showed best results were used for cultivation of dental pulp stem cell isolated from exfoliated teeth (SHED). Additional aims were to characterize DPSC and SHED and prove their ability to proliferate over Hayflick's limit and differentiate into mature cell lines (osteoblasts, chondroblasts and adipocytes). In order to find optimal protocols for isolation of dental pulp from tooth, we tried three different approaches. During optimization of cultivation protocol we focused on decreasing amount of fetal calf serum (FCS) from 10 % FCS in cultivation media (most often used in literature) into 2 % and thus get closer to cultivation conditions suitable for clinical usage. We compared DPSC cultivated in three different media (medium with 10 % FCS, 2 % FCS supplemented with growth factors and media with 2 % FCS supplemented with ITS and growth factors). For characterization of DPSC and SHED we used basic biological properties (proliferation activity, viability, morphology), their phenotype and karyotype. The study demonstrated that the best protocol for isolation of dental pulp from tooth was to break the roots and extract the pulp throw this aperture. We...
227

Electrochemical Aptasensing of B-Type Natriuretic Peptide-A Biomarker for Myocardial Infarction

Oranzie, Marlon January 2019 (has links)
>Magister Scientiae - MSc / infarction (MI) affects many parts of the western world and in South Africa alone it is estimated that MI is responsible for 1 in 6 deaths (17.3%). Traditional diagnostic methods for MI include an electrocardiograms and blood tests. The problem with these diagnostic methods are that they are time consuming, require large sample volumes, expensive equipment and complicated machinery. To achieve early detection of MI the discovery of specific, sensitive and reliable biomarkers are required. Brain natriuretic peptide (BNP) has been identified as a reliable biomarker for MI due to the fact that it has a defined cutoff of 100 pg/ml and it is not susceptible to patient‘s age which could make early detection of BNP complicated. Early detection methods for BNP has been based on immunoradiometric assays but problems associated with immunoradiometric assays are that there is a restricted availability of antigens and incubation of the labeled antibody could take up to two weeks which affects the patients waiting time on results. Electrochemical biosensors are emerging as early detection method for MI because they can be designed to be sensitive, specific to BNP at a low cost. This research study reported for the first the successful fabrication and implementation of highly sensitive mercaptosuccinic acid capped nickel selenide quantum dots (MSA-NiSe2 QDs) aptasensor for the detection of BNP. The poly-dispersed MSA-NiSe2 QDs were synthesized via an inexpensive, simple and reproducible aqueous microwave assisted irradiation method. The prepared MSA-NiSe2 QDs were characterized by Ultraviolet spectroscopy (UV-Vis), X-ray Diffraction (XRD), Fourier Transform Infrared spectroscopy (FTIR), High Resolution Transmission/Scanning Electron Microscopy (HR TEM/SEM) and Small Angle X-ray Scattering (SAXSpace). The electrochemical properties of the MSA-NiSe2 QDs were investigated by Cylic Voltammetry (CV) and Electrochemical Impedance Spectroscopy (EIS). HR-TEM revealed the formation of small sized MSA-NiSe2 QDs about 4 nm in diameter which was complemented by SAXSpace. UV-Vis studies showed absorption peaks in the ultraviolet region (100-400 nm) confirming the small size of these QDs as well confirming the direct and indirect bandgap of the QDs. XRD confirmed that the QDs are crystalline and belong to the bulk cubic MSA-NiSe2 QDs phase. FTIR studies confirmed the successful capping of MSA on the QDs due to the disappearance of the thiol peak at 2652 cm-1. Electrochemical studies revealed that the MSA-NiSe2 QDs showed good electrochemical properties on screen printed carbon electrodes (SPCE) which allowed them to be used as a mediating platform between the aptamer and SPCE. The successful detection of BNP was achieved by an incubation process between the aptamer drop coated on the MSA-NiSe2 QDs/SPCE surface overnight. The response of the MSA-NiSe2 QDs based aptasensor towards different concentrations of BNP was studied by differential pulse voltammetry (DPV). DPV showed a good linearly with correlation coefficient of R2 = 0.98. DPV also showed a high sensitivity (0.4513 μA/ pg/mL) towards detecting BNP with a detection limit of 11.93 pg/ml. The value of 11.93 pg/ml falls within the negative predictive value range of 10-100 pg/ml for early-stage diagnosis of BNP.
228

Stochastic Process Limits for Topological Functionals of Geometric Complexes

Andrew M Thomas (11009496) 23 July 2021 (has links)
<p>This dissertation establishes limit theory for topological functionals of geometric complexes from a stochastic process viewpoint. Standard filtrations of geometric complexes, such as the Čech and Vietoris-Rips complexes, have a natural parameter <i>r </i>which governs the formation of simplices: this is the basis for persistent homology. However, the parameter <i>r</i> may also be considered the time parameter of an appropriate stochastic process which summarizes the evolution of the filtration.</p><p>Here we examine the stochastic behavior of two of the foremost classes of topological functionals of such filtrations: the Betti numbers and the Euler characteristic. There are also two distinct setups in which the points underlying the complexes are generated, where the points are distributed randomly in <i>R<sup>d</sup></i> according to a general density (the traditional setup) and where the points lie in the tail of a heavy-tailed or exponentially-decaying “noise” distribution (the extreme-value theory (EVT) setup).<br></p><p>These results constitute some of the first results combining topological data analysis (TDA) and stochastic process theory. The first collection of results establishes stochastic process limits for Betti numbers of Čech complexes of Poisson and binomial point processes for two specific regimes in the traditional setup: the sparse regime—when the parameter <i>r </i>governing the formation of simplices causes the Betti numbers to concentrate on components of the lowest order; and the critical regime—when the parameter <i>r</i> is of the order <i>n<sup>-1/d</sup></i> and the geometric complex becomes highly connected with topological holes of every dimension. The second collection of results establishes a functional strong law of large numbers and a functional central limit theorem for the Euler characteristic of a random geometric complex for the critical regime in the traditional setup. The final collection of results establishes functional strong laws of large numbers for geometric complexes in the EVT setup for the two classes of “noise” densities mentioned above.<br></p>
229

A Paper Accepted for the Proceedings but not Presented at the Conference: Hypothesis Aided Approach to the Instruction of the Limit of a Function

Meznik, Ivan 22 May 2012 (has links)
The concept of the limit of a function is undoubtedly the key to higher mathematics. With a view to very fine mathematical essence of the notion mathematics educators permanently deliberate what didactic method to take in order to reach relatively satisfactory level of its understanding. The paper presents an approach based on the aid of hypothesis that is put forward by means of calculator support.
230

Optimale Strategien fuer spezielle Reparatursysteme / Optimal control of special repairable systems

Bruns, Peter 08 September 2000 (has links)
The thesis contains 3 repairable systems and 2 replacement systems: First a repairable system is considered with Markovian deterioration and imperfect repair, carried out at fixed times. We look for optimal strategies under certain conditions. Two optimality criteria are considered: expected discounted cost and long-run average cost. Conditions are found under which the optimal policy is a control-limit policy as used by Derman or Ross. We explicitly explain how to derive this optimal policy; numerical examples are given, too. The special case of unbounded cost is also studied. With the first model the state space is numerable but with the second it is not. With the fourth model the system occurs a shock process and is only inspected after such a shock. Models 3 and 5 are replacement systems with Morkovian deterioration and finite state space {0,...,N}. A system in state N is considered to be in a very serious situation. Hence there is the condition, e.g. stipulated by law, that the percentage of all replaced machines in state N in the group of all replaced machines may not be larger than 100 epsilon for a fixed epsilon in [0,1]. We prove that a generalized control limit policy maximizes the expected running time of a machine and we explain explicitly how to derive this optimal policy. Illustrated numerical examples are given.

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