Fakulta elektrotechniky a informatiky / Faculty of Electrical Engineering and Informatics
Stálý URI pro tuto komunituhttps://hdl.handle.net/10195/3847
Práce obhájené před rokem 2008 jsou uloženy pouze v kolekci Vysokoškolské kvalifikační práce
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Článekpeer-reviewedpublished version Omezený přístup The dissociation constants of the cytostatic bosutinib by nonlinear least-squares regression of multiwavelength spectrophotometric and potentiometric pH-titration data(2016) Meloun, Milan; Nečasová, Veronika; Javůrek, Milan; Pekárek, TomášPotentiometric and spectrophotometric pH-titration of the multiprotic cytostatics bosutinib for dissociation constants determination were compared. Bosutinib treats patients with positive chronic myeloid leukemia. Bosutinib exhibits four protonatable sites in a pH range from 2 to 11, where two pK are well separated (Delta pK>3), while the other two are near dissociation constants. In the neutral medium, bosutinib occurs in the slightly water soluble form LH that can be protonated to the soluble cation LH43+. The molecule LH can be dissociated to still difficultly soluble anion L-. The set of spectra upon pH from 2 to 11 in the 239.3-375.0 nm was divided into two absorption bands: the first one from 239.3 to 290.5 nm and the second from 312.3 to 375.0 nm, which differ in sensitivity of chromophores to a pH change. Estimates of pK of the entire set of spectra were compared with those of both absorption bands. Due to limited solubility of bosutinib the protonation in a mixed aqueous-methanolic medium was studied. In low methanol content of 3-6% three dissociation constants can be reliably determined with SPECFIT/32 and SQUAD(84) and after extrapolation to zero content of methanol they lead to pK(c1)=3.43(12), pK(c2)=4.54(10), pK(c3)=7.56(07) and pK(c4)=11.04(05) at 25 degrees C and pK(c1)=3.44(06), pK(c2)=5.03(08) pK(c3)=7.33(05) and pK(c4)=10.92(06) at 37 degrees C. With an increasing content of methanol in solvent the dissociation of bosutinib is suppressed and the percentage of LH32* decreases and LH prevails. From the potentiometric pH-titration at 25 degrees C the concentration dissociation constants were estimated with ESAB pK(c1)=3.51(02), pK(c2)=4.37(02), pK(c3)=7.97(02) and pK(c4)=11.05(03) and with HYPERQUAD: pK(c1)=3.29(12), pK(c2)=4.24(10), pK(c3)=7.95(07) and pK(c4)=11.29(05).Článekpeer-reviewedpublished version Omezený přístup Statistical Analysis of Ground Clutter from FM Based Passive Radar(Springer, 2019) Bhatta, Abhishek; Pidanič, Jan; Mishra, AmitStatistical characterization of ground clutter information for radar systems is a topic that requires a detailed understanding. In this work, we characterize the ground clutter information from data captured by two Frequency Modulation (FM) based passive radar systems placed at different locations in the Czech Republic. Since the target models are statistically defined by the Swerling models, each of which is based on a particular distribution, we attempted to connect the ground clutter with some of the known distributions. The analysis is performed in three steps. The empirical distribution is fitted with some of the well-known distributions. Two different goodness-of-fit tests (named chi-squared test and Kolmogorov-Smirnov test) are performed on the obtained data by comparing the empirical distribution with the fitted distributions to determine which distribution is the best fit. The observations are analyzed and the results are considered in detail.Článekpeer-reviewedpublished version Otevřený přístup Software tool for voice disorder diagnostics(Fakulta strojní. VŠB-TU Ostrava, 2019) Jičínský, Milan; Mareš, JanCauses of voice disorders may vary the same way as treatment techniques. Surgical intervention is the most used treatment method. As for not so serious cases, vocal exercises can be efficiently used instead. Still, there are only few methods to find right diagnosis or classify the scale of impact on patient’s voice. Nowadays, it is possible to extract key features (fundamental frequency, sound pressure level and less common such as cepstral coefficients, zero crossing rate or spectral energy) from patient’s speech using state-of-the-art voice processing methods. So, the software called Voice disorder diagnostician was designed. The tool that can store patient’s data and immediately provide the results of analysis.Článekpeer-reviewedpostprint Otevřený přístup Speaker Verification Using Autoregressive Spectrum of Speech Signal in Composite Vector Stochastic Processes Model Representation(Institute of Mechanics of Continua and Mathematical Sciences, 2019) Chmelařová, Natalija; Tykhonov, Vyacheslav A.; Bezruk, Valerij M.; Chmelař, Pavel; Rejfek, LubošThis paper deals with the speaker verification system similar to a fingerprint or an eye scanner. For these purpose a long-term words' model and its spectral characteristics were used. The speaker verification method uses the word's sound parametric spectrum factorization in composite vector stochastic process representation based on the multiplicative autoregressive model. The developed method enables to receive the words' features with stable characteristics for the same speaker and differ for different speakers. During the training phase speaker's etalon frequencies has to be estimated for a pronounced word repeated several times. In the verification phase a speaker pronouncing the same word, word's frequencies are estimated and compared with the etalon frequencies database to find the best match or his deny. The results presented in the paper showed the high correct identification probability.Článekpeer-reviewedpostprint Otevřený přístup Design a combination of filters to reduce decline the attenuation in magnitude response(WSEAS Press, 2019) Brtník, BohumilSome biquad filters structures are characterized by a decreasing of the attenuation at high frequencies, caused by the final value of the output resistance of the operational amplifier. This decreasing of the attenuation occurs only for the some even orders filters, i.e. for the biquads, of which a higher order filter is composed. One possible solution is to replace the biquad with another biquad that does not have this property. The conversion of parameters of such biquads to each other biquad is described in the detailed steps. The results of the proposed numerical procedure are verified by simulation.Článekpeer-reviewedpostprint Otevřený přístup Desired Terminal State Concept in Model Predictive Control: A Case Study(Hindawi limited, 2019) Dušek, František; Honc, DanielThe paper deals with an online optimization control method for dynamical processes called Model Predictive Control (MPC). It is a popular control method in industry and frequently treated in academic areas as well. The standard predictive controllers usually do not guarantee stability especially for the case of short horizons and large control error penalization. Terminal state is one way to ensure stability or at least increase the controller robustness. In the paper, deviation of the predicted terminal state from the desired terminal state is considered as one term of the cost function. Effect of the stability and control quality is demonstrated in the simulated experiments. The application area for online optimization methods is very broad including various logistics and transport problems. If the dynamics of the controlled processes cannot be neglected, the optimization problem must be solved not only for steady state but also for transient behaviour, e.g., by MPC.Konferenční objektpeer-reviewedpostprint Otevřený přístup Singularity subtraction in a multidimensional Fredholm integral equation of the second kind with a singular kernel(American Institute of Physics, 2019) Rak, JosefA numerical solution of the Fredholm integral equations can be obtained by many methods. Most of them lead to a solution of a system of linear equations with fully populated matrices. In the case of collocation or product integration methods, each element of the matrix is an integral, which needs to be calculated. It causes high computing time in multidimensional problems. Computing time can be reduced by the Nyström method. It is based on substitution of the integral by a numerical integration rule. It has the advantage that only diagonal elements of the matrix are integrals. When the kernel function is singular, a singularity subtraction is needed. However it can not be used for every kernel function and every integration rule. The main point of this paper is the convergence conditions of the Nyström method as applied to a special multidimensional integral equation. The paper includes an illustrative example.Konferenční objektpeer-reviewedpostprint Otevřený přístup Adaptive Pulse Compression Filter in Radar Receiver Application(IEEE (Institute of Electrical and Electronics Engineers), 2019) Bezoušek, Pavel; Karamazov, Simeon; Roleček, JiříIn the paper the matched compression filter, the compression filter with minimum sidelobe energy and with maximum peak to sidelobe ratio for linear and nonlinear frequency modulated signals are presented and compared. Then application of those filters in radars in various clutter situations are discussed.Konferenční objektpeer-reviewedpostprint Otevřený přístup Nonlinear distortion in a microwave high power amplifier(IEEE (Institute of Electrical and Electronics Engineers), 2019) Bezoušek, Pavel; Matoušek, David; Rejfek, LubošIn this paper the high-power amplifier CGHV31500F designed for the radar S-Band application is studied. The amplifier module is based on GaN HEMT encapsulated internally matched transistor, delivering more than 500 W in a pulse regime. Nonlinear model of this amplifier was developed and nonlinear distortion of a standard radar signal and of possible future QAM signals are predicted.Konferenční objektpeer-reviewedpostprint Omezený přístup MONDAY EFFECT ON STOCK PRICES: TESTING OF STATISTICAL HYPOTHESIS(Slovenská technická univezita v Bratislave, 2019) Pozdílková, AlenaThe aim of this article will be to analyse one of calendar effects - Monday effect. In testing, we will not just go through analysing price returns, but we will study the values of the measurement of investment success. Therefore, we will determine the Win Ratio, Profit Factor, and Profit Loss Ratio. For hypothesis testing, we suggest appropriate statistical tests. We will work with the prices of the period from January 2005 to October 2018 for 29 stock companies that are part of the DJA index.