National Repository of Grey Literature 36,524 records found  beginprevious36515 - 36524  jump to record: Search took 2.19 seconds. 

Energetic utilization of wastewater
Žáček, Jan ; Raček, Jakub (referee) ; Hlavínek, Petr (advisor)
Diploma thesis presents various methods of energetic utilization of wastewater. It shows that wastewater is source of heat energy that has not been used yet. The thesis focuses mainly on heat recovery from wastewater from sewer bypass by modular heat exchangers. Design of heating of polyfunctional building from bypass from main sewer in Brno is developed. The main finding is that wastewater as low potential source of energy can together with heat pump be not only used for heating and heating of domestic hot water but also for cooling of polyfunctional object. Part of work is also technical-economical assessment by the NPV method.

Development of Diffusive Gradients in Thin Films Technique for Determination of Mercury in Aquatic Systems
Szkandera, Roman ; Chýlková, Jaromíra (referee) ; Čelechovská, Olga (referee) ; Řehůřková, Irena (referee) ; Dočekalová, Hana (advisor)
The theoretical part of this doctoral thesis deals with determination of mercury and its species in aquatic systems. Special attention is paid to the use in situ sampling technique diffusive gradients in thin films technique (DGT) and its development. Current resin gels used for determination of mercury by DGT technique Duolite GT-73, Chelex-100 and Spheron-Thiol are described. Moreover, new types of resin gels including Iontosorb AV modified by imidazole or 6-mercaptopurine and commercially available titanium dioxide. Preparations of resin gels and their basic tests in model solution according to DGT Research are described. Mercury accumulation in relation to time and basic recovery test were tested and capacity of resins was determined. All tested resins meet the requirements of basic DGT Research tests and relative standard deviations of mercury in recovery tests were lower than 10 %. The sorption capacity of resins varied from 1,5 to 6 µmol.l-1 and decreased in following order: Duolite GT-73 > ISAV-IM > Chelex-100 > Spheron-Thiol > TiO2 > ISAV-MP. Mercury sorption on resins was investigated under conditions similar to those in natural waters. It was found that the ionic strength commonly occurring in natural waters does not affect the determination of mercury. The presence of chlorides significantly affects the determination of mercury using DGT with titanium dioxide and therefore this sorbent can not be recommended for the determination of mercury in sea waters. The accumulated amount of mercury, depending on the pH shows that all the sorbents can be used in natural waters with pH in the range form 4 to 8. Mercury sorption is most affected by the presence of humic acids, especially at ion-exchange resins containing other than thiol functional groups. The exception is titanium dioxide for which physical sorption of humic acid metal complexes is typical. Cadmium and copper in model solutions in the molar balance of the excess mostly influenced the sorption of mercury on Chelex-100 and Spheron-Thiol resins. After laboratory tests, the DGT units with studied sorbents were used for the determination of mercury in natural waters of South Moravia (Svratka, Jihlava and Svitava river). Mercury concentration determined using DGT units containing Duolite GT-73 resin was comparable to the total dissolved concentration of mercury in river water provided by direct determination using AAS technique. Order of magnitude smaller concentrations than the total dissolved mercury concentration were found using DGT containing Spheron-Thiol and ISAV-MP resins. These sorbents are probably able to capture only mercury present in the form of labile complexes. This can be used for speciation analysis if more DGT units with different resins are deployed together. Subtracting the measured DGT Spheron-Thiol or ISAV-MP concentrations from the DGT Duolite GT-73 concentration, information about the amount of mercury present in the form of stabile complexes can be obtained. The amount of mercury determined after application of DGT units containing ISAV-IM, Chelex 100 or TiO2 can probably represent the mercury fraction bound in even weaker complexes than fraction determined by Spheron-Thiol and ISAV-MP DGT.

Real-Time Data Exchange technology and its applications
Meluzín, Ivo ; Šilhavý, Pavel (referee) ; Krajsa, Ondřej (advisor)
Bachelor ‘s thesis target the analysis of the Real-Time Data eXchange technology. There are mentioned some preferences for using kit development of TMS320C6416 DSK invented by Texas Instruments Inc., in the way of signal porcessing with help of some software applications. On these basis, there is built a model in Simulink. Sequentially, we activate whole system, which is running on developer‘s kit for methods of counting, processing and reading data from interface RTDX.

Security Portfolio Optimalization
Roušavý, Jan ; Zerzánek, Ivan (referee) ; Sojka, Zdeněk (advisor)
Diploma thesis focuses on the issue of an appropriate selection of securities and the subsequent establishment of a portfolio of these securities. Follow detailed discussion about analysis of portfolio and investor’s preferences. Below is a description of the CAPM model, its assumptions and usage of this model to build a portfolio. Then there is the actual calculation of characteristics of securities traded on the Prague Stock Exchange and on the basis of these calculations is made the proposal of several portfolios and their evaluation.

Labour Market Modelling within a DSGE Approach
Tonner, Jaromír ; Tvrz, Stanislav ; Vašíček, Osvald
The goal of this paper is to find a suitable way of modelling the main labour market variables in the framework of the CNB’s core DSGE model. The model selection criteria are: the predictive ability for unemployment, the change in the overall predictive ability in comparison to the baseline model and the extent of the required model change. We find that the incorporation of a modified Galí, Smets and Wouters (2011) labour market specification allows us to predict unemployment with an acceptable forecast error. At the same time it leads to a moderate improvement in the overall predictive ability of the model and requires only minor adjustments to the model structure. Thus, it should be preferred to more complicated concepts that yield a similar improvement in predictive ability. We also came to the conclusion that the concept linking unemployment and the GDP gap is promising. However, its practical application would require (additional) improvement in the accuracy of the consumption prediction. As a practical experiment, we compare the inflation pressures arising from nominal wages and the exchange rate in the baseline model and in alternative specifications. The experiment is motivated by the use of the exchange rate as an additional monetary policy instrument by the CNB since November 2013 in an environment of near-zero interest rates and growing disinflationary pressures. We find that the baseline model tends to forecast higher nominal wage growth and lower exchange rate depreciation than the models with more elaborate labour markets. Therefore, the alternative models would probably have identified an even higher need for exchange rate depreciation than the baseline model did.
Fulltext: Download fulltextPDF

Valuation of PX Index Options with NGARCH Volatility and Time Dependent Expected Risk Free Rate
Štěrba, Filip ; Málek, Jiří (advisor) ; Kodera, Jan (referee) ; Hnilica, Jiří (referee)
The main purpose of this thesis is to propose the valuation method of PX index options. PX index consists of blue chip stocks traded on Prague Stock Exchange. There are traded a few futures contracts on PX index on Prague Stock Exchange. However, the options on PX index are traded neither on Prague Stock Exchange nor on the OTC market. It is reasonable to think that it is only question of time when the trading of these options will emerge and thus, it is highly relevant subject of research to propose the method for valuation of these options. The traditional Merton's approach for valuation of equity index options assumes constant volatility and constant risk free rate. This results in serious mispricing which can be easily seen when we compare market prices and Merton formula derived prices. Instead, this thesis releases the assumptions of constant risk free rate and constant volatility. Firstly, it is assumed that that the risk free rate is time dependent function based on current market expectations and secondly it is assumed that the volatility of underlying asset follows NGARCH-mean process. For the purpose of former, the validity of pure expectation theory assumption is made. This enables to employ the instantaneous forward rate curve estimation procedure. For the purpose of the latter, the locally risk-neutral valuation relationship is applied. The assumption of NGARCH-mean process is essential in an effort to capture usually observed patterns of volatility (volatility skews) whereas the assumption of time dependent risk free rate still moves the valuation option model closer to the reality. The author derives the expected path of risk free rate and estimates the parameters of NGARCH process. Subsequently, the empirical martingale Monte Carlo simulation is used to price the PX options with different moneyness and with different times to maturity. It is shown that this proposed model results in volatility pattern which is usually observed on developed markets and the author's results are in line with similar empirical studies testing the GARCH Option Pricing Theory. The author concludes that proposed valuation method superiors original Merton's model and thus is more appropriate for primary valuation of PX options.

Backtesting of Time Series Models
Stroukalová, Marika ; Houfková, Lucia (advisor) ; Zichová, Jitka (referee)
Title: Backtesting of Time Series Models Author: Marika Stroukalová Department: Department of Probability and Mathematical Statistics Supervisor: Mgr. Lucia Jarešová Supervisor's e-mail address: lucia.jaresova@centrum.cz Abstract: In the present work we study the basic models of financial time series (ARMA, GARCH), we focus on parameter estimation and forecasting in estimated models. We describe the means of estimating parametres and future values in the program R. In the theoretical section we also discuss the features of financial time series, define simple returns and log returns and we introduce the benefits of the log returns. We also apply the white noise model, ARMA(1,1) and GARCH(1,1) on historic time series of logarithmic returns of chosen stock exchange indices, we also backtest 1-step ahead fore- cats and 5-step ahead forecasts and we compare the results of these models. By empirical comparison of real data we also analyze how the models reac- ted on the present financial crisis and evaluate how the normal distribution assumption for the data held up. Keywords: time series, ARMA, GARCH, backtesting. 1

Mining XML Integrity Constraints
Fajt, Stanislav ; Nečaský, Martin (advisor) ; Svoboda, Martin (referee)
The most important integrity constraints in XML are primary keys and foreign keys. In general, keys are essential in understanding both the structure and properties of data. They provide an instrument by which va- lues from a given set of attributes uniquely identify tuples in a database. As a result, keys are important to main database operations. Since XML beco- mes lingua franca for data exchange on the web, it is widely accepted as a model of real world data. Because XML documents in general can appear in any semi-structured form, structural constraints (including keys) are often imposed on the data that are to be modified or processed These constra- ints are formally defined in a schema.Unfortunately, in spite of the obvious advantages, the presence of a schema is not mandatory and many XML do- cuments are not joined with any. Consequently, no integrity constratins are specified in those documents, neither. This thesis is mainly focused on the inference of primary and foreign keys from XML documents. 1

Cytogenetic methods in genotoxicology
Bártů, Linda ; Langová, Martina (referee) ; Daňková, Pavlína (advisor)
We are constantly exposed to a variety of factors which may be a cause of DNA mutations. The influence of mutagens of physical, chemical and biological origin is studied by genotoxicology. Ionic radiation is among the most common physical mutagens, benzene, vinylchloride or some drugs represent the chemical mutagens, while some viruses and may act as biological mutagens. The repair mechanisms of double strand breaks can be divided into those that require HRR-homologous sequences and those that may use of microhomologies consisting of a short DNA sequence (NHEJ). Both mechanisms can lead to aberrations of chromosomes, if they are not precise. Acquired chromosomal aberrations include translocation, common in cancer cells; deletion; or the production of acentric fragments, dicentrics and rings. Chromatid aberrations includes chromatid breaks and chromatide exchanges. There are various methods for detecting/examining such mutations and these can be categorised according to the phases of the cell cycle. The basic method is clasic Giemsa stain which reveals the most of aberrations except translocations and inversions and numeric abnormalities in metaphasic cells. Another way of testing mutagenicity is determining the rate of sister chromatide exchange; or the so called micronucleus test used to measure...

Fundamental analysis of Erste Bank shares listed on the Prague Stock Exchange
Petr, Pavel ; Veselá, Jitka (advisor)
This bachelor thesis is an attempt by the methods of fundamental analysis to evaluate all the relevant factors that are relevant in the process of evaluation shares. The aim of this work is to prepare investment recommendations on the shares of Erste Bank. The first chapter is the theoretical background of all the analytical methods used in the stock market. In particular, technical analysis, efficient markets theory, psychological analysis and fundamental analysis. The second chapter is devoted to the global analysis. Global analysis is supplemented by regression analysis of each of evaluated factors. Another chapter deals with the sectoral analysis as insight into the banking sector in the Czech Republic, partly in Central Europe. The fourth chapter contains its own internal calculation of value shares, compared with the current rate of investment and the resulting recommendations.