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Clustering and regression analysis of micro panel data
Sobíšek, Lukáš ; Pecáková, Iva (advisor) ; Komárek, Arnošt (referee) ; Brabec, Marek (referee)
The main purpose of panel studies is to analyze changes in values of studied variables over time. In micro panel research, a large number of elements are periodically observed within the relatively short time period of just a few years. Moreover, the number of repeated measurements is small. This dissertation deals with contemporary approaches to the regression and the clustering analysis of micro panel data. One of the approaches to the micro panel analysis is to use multivariate statistical models originally designed for crosssectional data and modify them in order to take into account the within-subject correlation. The thesis summarizes available tools for the regression analysis of micro panel data. The known and currently used linear mixed effects models for a normally distributed dependent variable are recapitulated. Besides that, new approaches for analysis of a response variable with other than normal distribution are presented. These approaches include the generalized marginal linear model, the generalized linear mixed effects model and the Bayesian modelling approach. In addition to describing the aforementioned models, the paper also includes a brief overview of their implementation in the R software. The difficulty with the regression models adjusted for micro panel data is the ambiguity of their parameters estimation. This thesis proposes a way to improve the estimations through the cluster analysis. For this reason, the thesis also contains a description of methods of the cluster analysis of micro panel data. Because supply of the methods is limited, the main goal of this paper is to devise its own two-step approach for clustering micro panel data. In the first step, the panel data are transformed into a static form using a set of proposed characteristics of dynamics. These characteristics represent different features of time course of the observed variables. In the second step, the elements are clustered by conventional spatial clustering techniques (agglomerative clustering and the C-means partitioning). The clustering is based on a dissimilarity matrix of the values of clustering variables calculated in the first step. Another goal of this paper is to find out whether the suggested procedure leads to an improvement in quality of the regression models for this type of data. By means of a simulation study, the procedure drafted herein is compared to the procedure applied in the kml package of the R software, as well as to the clustering characteristics proposed by Urso (2004). The simulation study demonstrated better results of the proposed combination of clustering variables as compared to the other combinations currently used. A corresponding script written in the R-language represents another benefit of this paper. It is available on the attached CD and it can be used for analyses of readers own micro panel data.
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Possibilities of Big Data use for Competitive Intelligence
Verníček, Marek ; Molnár, Zdeněk (advisor) ; Šperková, Lucie (referee)
The main purpose of this thesis is to investigate the use of Big Data for the methods and procedures of Competitive Intelligence. Among the goals of the work is a toolkit for small and large businesses which is supposed to support their work with the whole process of Big Data work. Another goal is to design an effective solution of processing Big Data to gain a competitive advantage in business. The theoretical part of the work processes available scientific literature in the Czech Republic and abroad as well as describes the current state of Competitive Intelligence, and Big Data as one of its possible sources. Subsequently, the work deals with the characteristics of Big Data, the differences from working with common data, the need for a thorough preparation and Big Data applicability for the methods of Competitive Intelligence. The practical part is focused on analysis of Big Data tools available in the market with regard to the whole process from data collection to the analysis report preparation and integration of the entire solution into an automated state. The outcome of this part is the Big Data software toolkit for small and large businesses based on their budget. The final part of the work is devoted to the classification of the most promising business areas, which can benefit from the use of Big Data the most in order to gain competitive advantages and proposes the most effective solution of working with Big Data. Among other benefits of this work are expansion of the range of resources for Competitive Intelligence and in-depth analysis of possibilities of Big Data usage, designed to help professionals make use of this hitherto untapped potential to improve market position, gain new customers and strengthen the existing user base.
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Height measurement in the northern area of mining areas Doubrava and Karviná Mines In 2016
Kajzar, Vlastimil ; Waclawik, Petr ; Staš, Lubomír
In the northern area of mining areas Doubrava and Karvina mines on the border RA Detmarovice and Doubrava are implemented, the mining activities. For this reason, in order to detect possible effects of the mine to the surface and surface objects twice a year height focuses, points in this area stable. From 2014 he was a contractor for these works chosen by the Institute of Geonics, v.v.i., Ostrava. In August and November 2016 survey conducted campaigns planned this year, during which it conducted a total of 4 highrise focus of inter-related leveling routes, which are formed by these points. Highrise points are stabilized in the area of interest in several ways - usually in steel design height marks on buildings, then as an iron bolt concreted in the ground or using nails driven into the concrete foundation or other alternative means. Distribution points in the area of interest is indicative captured in the map appendix. Existing trace and focus points are highlighted in green, yellow trace inaccessible points, refocused points in red and violet points that have occurred to their long term disablement or destruction. Each zaměřovaných points in order to trace the terrain carefully documented (GPS coordinates, photos, text description) and registered. These documents are available from the contractor.
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Modelling, parameter estimation, optimisation and control of transport and reaction processes in bioreactors.
ŠTUMBAUER, Václav
With the significant potential of microalgae as a major biofuel source of the future, a considerable scientific attention is attracted towards the field of biotechnology and bioprocess engineering. Nevertheless the current photobioreactor (PBR) design methods are still too empirical. With this work I would like to promote the idea of designing a production system, such as a PBR, completely \emph{in silico}, thus allowing for the in silico optimization and optimal control determination. The thesis deals with the PBR modeling and simulation. It addresses two crucial issues in the current state-of-the-art PBR modeling. The first issue relevant to the deficiency of the currently available models - the incorrect or insufficient treatment of either the transport process modeling, the reaction modeling or the coupling between these two models. A correct treatment of both the transport and the reaction phenomena is proposed in the thesis - in the form of a unified modeling framework consisting of three interconnected parts - (i) the state system, (ii) the fluid-dynamic model and (iii) optimal control determination. The proposed model structure allows prediction of the PBR performance with respect to the modelled PBR size, geometry, operating conditions or a particular microalgae strain. The proposed unified modeling approach is applied to the case of the Couette-Taylor photobioreactor (CTBR) where it is used for the optimal control solution. The PBR represents a complex multiscale problem and especially in the case of the production scale systems, the associated computational costs are paramount. This is the second crucial issue addressed in the thesis. With respect to the computational complexity, the fluid dynamics simulation is the most costly part of the PBR simulation. To model the fluid flow with the classical CFD (Computational Fluid Dynamics) methods inside a production scale PBR leads to an enormous grid size. This usually requires a parallel implementation of the solver but in the parallelization of the classical methods lies another relevant issue - that of the amount of data the individual nodes must interchange with each other. The thesis addresses the performance relevant issues by proposing and evaluation alternative approaches to the fluid flow simulation. These approaches are more suitable to the parallel implementation than the classical methods because of their rather local character in comparison to the classical methods - namely the Lattice Boltzmann Method (LBM) for fluid flow, which is the primary focus of the thesis in this regard and alternatively also the discrete random walk based method (DRW). As the outcome of the thesis I have developed and validated a new Lagrangian general modeling approach to the transport and reaction processes in PBR - a framework based on the Lattice Boltzmann method (LBM) and the model of the Photosynthetic Factory (PSF) that models correctly the transport and reaction processes and their coupling. Further I have implemented a software prototype based on the proposed modeling approach and validated this prototype on the case of the Coutte-Taylor PBR. I have also demonstrated that the modeling approach has a significant potential from the computational costs point of view by implementing and validating the software prototype on the parallel architecture of CUDA (Compute Unified Device Architecture). The current parallel implementation is approximately 20 times faster than the unparallized one and decreases thus significantly the iteration cycle of the PBR design process.
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Packet Classification Algorithms
Puš, Viktor ; Lhotka,, Ladislav (referee) ; Dvořák, Václav (advisor)
Tato práce se zabývá klasifikací paketů v počítačových sítích. Klasifikace paketů je klíčovou úlohou mnoha síťových zařízení, především paketových filtrů - firewallů. Práce se tedy týká oblasti počítačové bezpečnosti. Práce je zaměřena na vysokorychlostní sítě s přenosovou rychlostí 100 Gb/s a více. V těchto případech nelze použít pro klasifikaci obecné procesory, které svým výkonem zdaleka nevyhovují požadavkům na rychlost. Proto se využívají specializované technické prostředky, především obvody ASIC a FPGA. Neméně důležitý je také samotný algoritmus klasifikace. Existuje mnoho algoritmů klasifikace paketů předpokládajících hardwarovou implementaci, přesto však tyto přístupy nejsou připraveny pro velmi rychlé sítě. Dizertační práce se proto zabývá návrhem nových algoritmů klasifikace paketů se zaměřením na vysokorychlostní implementaci ve specializovaném hardware. Je navržen algoritmus, který dělí problém klasifikace na jednodušší podproblémy. Prvním krokem je operace vyhledání nejdelšího shodného prefixu, používaná také při směrování paketů v IP sítích. Tato práce předpokládá využití některého existujícího přístupu, neboť již byly prezentovány algoritmy s dostatečnou rychlostí. Následujícím krokem je mapování nalezených prefixů na číslo pravidla. V této části práce přináší vylepšení využitím na míru vytvořené hashovací funkce. Díky použití hashovací funkce lze mapování provést v konstantním čase a využít při tom pouze jednu paměť s úzkým datovým rozhraním. Rychlost tohoto algoritmu lze určit analyticky a nezávisí na počtu pravidel ani na charakteru síťového provozu. S využitím dostupných součástek lze dosáhnout propustnosti 266 milionů paketů za sekundu. Následující tři algoritmy uvedené v této práci snižují paměťové nároky prvního algoritmu, aniž by ovlivňovaly rychlost. Druhý algoritmus snižuje velikost paměti o 11 % až 96 % v závislosti na sadě pravidel. Nevýhodu nízké stability odstraňuje třetí algoritmus, který v porovnání s prvním zmenšuje paměťové nároky o 31 % až 84 %. Čtvrtý algoritmus kombinuje třetí algoritmus se starším přístupem a díky využití několika technik zmenšuje paměťové nároky o 73 % až 99 %.
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Measurement of \kur{in situ}Phasporus Availability in Acidified Soils using Iron-Infused Resin soils.
ČAPEK, Petr
A hybrid anion resin was tested for in situ phosphorus (P) availability measurement in soils of two stands recovering from acidification and having different P-sorption characteristics. The phosphate (P-PO4) sorption capacity of the resin (before saturation) was 48 mol g-1. Sorption and elution were tested under P-PO4 concentrations common in acidic soils (0 0.42 mmol l-1) either with or without the presence of sulfate (0.2 mmol l-1). The efficiency of P-PO4 sorption was independent of the sulfate and was 100 +/- 0.2% (n = 56, +/- SD). The P-PO4 recovery stabilized after six elution steps (each: 50 ml of 0.5 M sodium hydroxide, resin/solution 5:1). The efficiency of P-PO4 recovery was 80 +/- 7% and was used to evaluate field measurements. We determined the amount of P-PO4 in the field using resin bags in three consecutive years. The results indicate that bioavailable P is negatively related to the soil ability to retain P.
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Crystallographic study of the iron-regulated outer membrane lipoprotein (FrpD) from Neisseria meningitidis
SVIRIDOVA, Ekaterina
Neisseria meningitidis (N. meningitidis) is a Gram-negative commensal bacterium colonizing nasopharynx of about 10 % of healthy individuals, which can cause invasive diseases, such sepsis and meningitis, upon occasional penetration into bloodstream. Pathogenesis of N. meningitidis appears to be directly related to conditions of limited iron availability. Under these conditions two proteins of unknown function: FrpC and FrpD, are synthesized. FrpD is a highly conserved lipoprotein of N. meningitidis anchored to the bacterial outer membrane. It is known that FrpD tightly binds the FrpC protein, which belongs to the Repeat-in-Toxin (RTX) protein family and may act as bacterial exotoxin. However, the mechanism of FrpD-FrpC interaction and the exact function of this complex are unknown due to the absence of structural information on these proteins. Therefore, we set out to determine the structure of FrpD and provide insights into its interaction mechanism with FrpC and structure-functional relationships of these two proteins. We determined the first crystal and solution structures of the FrpD protein. We found that atomic structures of FrpD reveal a novel protein fold. We uncovered the structure-function relationships underlying the mechanism of interaction between the FrpD and FrpC proteins and tested the putative function of the FrpD-FrpC1-414 complex in vitro. Finally, we proposed the putative function of the FrpD-FrpC1-414 complex as a new minor adhesin of N. meningitidis, which mediates the bacterial adhesion to the host epithelial cells and facilitate the colonization. Our work constitutes the first step in clarifying the molecular basis of the FrpD-FrpC interaction and sets the base for further investigation of the role of FrpD and FrpC in the virulence mechanism of N. meningitidis.
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Role fosforu v biologické aktivitě kryogenních půd
ČAPEK, Petr
The combined effect of temperature, moisture and phosphorus availability on soil organic matter mineralization in permafrost affected soils of northern circumpolar region was investigated. This study was a part of research activities of the European project CryoCARB and it was primarily focused on the cryoturbated organic horizons of permafrost affected soils. During this study, the temperature sensitivity of the organic matter mineralization and its relation to the soil moisture and phosphorus availability was investigated using series of incubation experiments and field measurements.
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The Role of Nurse in the Prevention of Disease of Civilisation
PAVLOVÁ, Martina
The current state Prevention is a complex care of a patient when we are trying to prevent from the occurrence or development of a disease, or when we want to prevent from its consequences and mitigate them. Recommendations for prevention set by a doctor must be on a scientific basis, and they must be a part of all branches of medicine. Their effectiveness depends on the cooperation between patients and medical staff. The basic and most efficient method of prevention is the health promotion and health education, which is closely associated with it. The term health promotion involves a set of activities and precautions for the purpose of making health better and sustaining it. Diseases of civilisation (hereinafter "DoC") are groups of diseases which are distinguished by their association to our lifestyles. Human body is more and more threatened from unfavourable influences of external environment, such as the quality of atmosphere, work environment and environment itself, the lack of physical movement, unhealthy diet, smoking, and alcohol consumption. The list of diseases of civilisation varies and changes together with our society and the development of our lifestyles. Among the most common or frequent diseases of current time are cardiovascular diseases, which involve atherosclerosis, hypertension, myocardial infarction, stroke, coronary artery disease and obesity. Furthermore, between civilization diseases include diabetes mellitus type 2 or cancer, etc. The goal of the thesis There are two goals set for this paper. The first goal was to find out what the role of a nurse in the prevention of diseases of civilisation was. The second goal was to find out what the above mentioned role of a nurse was from the point of view of patients. Methodology For the purpose of the research part of this thesis, qualitative research using semistructured interviews was carried out. Respondents were divided into two groups; the first one consisted of eight nurses working at internal medicine and neurological department of the hospital in České Budějovice and a nurse working in a private office of a general practitioner for adult patients. The second group consisted of eight patients of the above mentioned health facilities. Results According to our findings, nurses and patients have different oppinions on the role of a nurse. Nurses in disease prevention see themselves as an equivalent to a doctor when undertaking this practice and giving guidance. The patient speaks only to the nurse who emphasized what they were told by the doctor and reiterated the main points. They make available to them leaflets and brochures or Internet resources. In contrast, most patients see a nurse as a more important source of information than the doctor. Patients have the feeling that the doctor does not have enough time or does not want to be botherd with questions. Rather the patient turns to his nurse, which they sees as more appropriate and someone to whom they can confide in without bothering. Summary The goal of the thesis was to focus on prevention, DoC, and the role of a nurse in the prevention of such diseases, as well as to study this issue, look at it from the point of view of patients and nurses via the interviews carried out in this paper, and to analyse such information. Based on this analysis are published recommendations for nurses and patients.
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