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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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Plasma spraying from liquids: plasma liquid interaction and coating build up
Tesař, Tomáš ; Mušálek, Radek ; Medřický, Jan ; Lukáč, František
Plasma spraying from liquid feedstocks is a rapidly developing field of thermal spraying since the coatings prepared from liquids exhibit some unique features, such as high hardness, thermal shock resistance or low thermal and electric conductivity. The key factor influencing the final coating character and properties is the input material which may be in the form of a suspension or a solution. Parameters of the selected suspension (solids concentration, viscosity, surface tension, chemical composition, etc.) or solution (concentration, etc.) determine its interaction with the plasma jet which strongly influences the coating buildup. This proceeding introduces the problematics of the interaction between the liquid feedstock material with the plasma jet and presents the way of evaluation of the coating buildup.
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Preliminary evaluation of sites for long-term safety - a detailed factual and timetable of work
Havlová, V. ; Pertoldová, J. ; Mixa, P. ; Uhlík, J. ; Vavro, Martin ; Maryška, J. ; Černík, M. ; Vašíček, R.
Tato zpráva obsahuje Podrobný věcný a časový harmonogram prací ZL Předběžné hodnocení lokalit z hlediska dlouhodobé bezpečnosti, zaměřeného na hodnocení vhodnosti lokalit pro umístění hlubinného úložiště VJP a RAO na základě archivních informací, , také na základě průběžných výsledků ze probíhajících projektů a geologického průzkumu prováděného pomocí metod prováděných z povrchu. \nLokality budou hodnoceny podle následujících charakteristik, důležitých pro dlouhodobou bezpečnost:\n1) Popsatelnost a predikovatelnost lokality\n2) Hydrogeologické vlastnosti horninového prostředí\n3) Stabilita lokality (seismické, klimatické, vertikální pohyby, postvulkanické jevy)\n4) Pravděpodobnost intruze/invaze člověka do úložiště\n5) Transportní vlastnosti horninového prostředí\n6) Slučitelnost horninového prostředí s navrženým systémem inženýrských bariér\nŘešení bude probíhat v 5 etapách\n1) Podrobný věcný a časový plán řešení projektu \n2) Hodnocení lokality Čihadlo (první fáze)\n3) Hodnocení ostatních lokalit (první fáze)\n4) Hierarchie kritérií či indikátorů vhodnosti lokalit a způsob hodnocení lokalit \n5) Hodnocení lokalit (druhá fáze)\nŘešení projektu je zajištěno účastí širokého týmu řešitelů, kteří buď participují na řešení probíhajícího projektu Výzkumná podpora hodnocení lokality, nebo splňují vysokou kvalitu odborné erudice.\n
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Evaluation of the effectiveness of teaching vocational subjects depending on physical activity before schooling.
Janošíková, Martina ; Hanušová, Marie (advisor)
The period of transition to secondary school brings substantial changes in the requirements for study obligations, autonomy, communication, expression, or separated from their families in the form of staying at the dormitory. Students enrolled in sport centers, in addition to these changes, still struggling with the responsibilities associated with sport. Because they are students first through fourth grades of secondary schools and secondary vocational schools, an age when image self-I am, what I believe in, arises in interactions with the outside world and their own experience, plays a very important role to influence the environment, educators, teachers and trainers, with which students spend most of their time in practice. This study looks at students comprehensively in terms of personal development as a multifactorial biopsychosocial unit, in terms of cognitive and motivational processes, states and properties from the perspective of social psychology dealing with the interactions, relationships and communication, psychology of individuals within the social group and its importance for the development of the individual . It monitors conditions and educational outcomes in terms of educational psychology, dealing with forming properties, opinions, attitudes and value orientation from the perspective of educational psychology.
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Effect of snowpack on runoff generation during rain on snow event.
Juras, Roman ; Máca, Petr (advisor) ; Ladislav , Ladislav (referee)
During a winter season, when snow covers the watershed, the frequency of rain-on-snow (ROS) events is still raising. ROS can cause severe natural hazards like floods or wet avalanches. Prediction of ROS effects is linked to better understanding of snowpack runoff dynamics and its composition. Deploying rainfall simulation together with hydrological tracers was tested as a convenient tool for this purpose. Overall 18 sprinkling experiments were conducted on snow featuring different initial conditions in mountainous regions over middle and western Europe.
Dye tracer brilliant blue (FCF) was used for flow regime determination, because it enables to visualise preferential paths and layers interface. Snowpack runoff composition was assessed by hydrograph separation method, which provided appropriate results with acceptable uncertainty. It was not possible to use concurrently these two techniques because of technical reasons, however it would extend our gained knowledge. Snowmelt water amount in the snowpack runoff was estimated by energy balance (EB) equation, which is very efficient but quality inputs demanding. This was also the reason, why EB was deployed within only single experiment.
Timing of snowpack runoff onset decrease mainly with the rain intensity. Initial snowpack properties like bulk density or wetness are less important for time of runoff generation compared to the rain intensity. On the other het when same rain intensity was applied, non-ripe snowpack featuring less bulk density created runoff faster than the ripe snowpack featuring higher bulk density. Snowpack runoff magnitude mainly depends on the snowpack initial saturation. Ripe snowpack with higher saturation enabled to generate higher cumulative runoff where contributed by max 50 %. In contrary, rainwater travelled through the non-ripe snowpack relatively fast and contributed runoff by approx. 80 %.
Runoff prediction was tested by deploying Richards equation included in SNOWPACK model. The model was modified using a dual-domain approach to better simulate snowpack runoff under preferential flow conditions. Presented approach demonstrated an improvement in all simulated aspects compared to the more traditional method when only matrix flow is considered.
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Design of Experiment for Non-Stationary Processes of Production
Jadrná, Monika ; Macák, Tomáš (advisor)
The doctoral thesis is concerned with the services sector and the area of mass production. Particularly, the optimization of the product portfolio of the travel agency and the optimization of production rounds of ammunition.
The theoretical part deals with the current overview of discussed topic. Further, the terminology and methods of the decision-making process are defined to support decision making. The theoretical basis of research focused on the choice of appropriate input variables in the area of services, and on the choice of a particular material option in the production area and appropriate equipment for the production. The theoretical part forms the basis for the practical part of the thesis.
For the doctoral thesis was chosen an enterprise operating in the defined sector. Product portfolio for the services sector is optimised using Fuzzy logic and Fuzzy sets so that the enterprise can maintain its competitiveness in todays highly ambitious market. Product portfolio for manufacture is optimised for achieving desired properties of the product.
The main aim of the thesis is to propose a new methodological approach for the management of selected business processes in their nonstationary time course. The aim of the practical implementation is to verify the functionality of the proposed methodological approach, both in the area of services and in the field of mass production.
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The use of biomass ash
Ochecová, Pavla ; Tlustoš, Pavel (advisor) ; Radim, Radim (referee)
One of the most frequently used sources of renewable energy is biomass, mainly wood biomass. Incineration is the most common technology utilizing the energy from biomass to produce heat. A byproduct of these technologies is ash, whose composition depends on the feedstock composition and the incineration technologies. Due to the high content of valuable nutrients in ash, one of the suitable option for ash utilization seems to be application into agricultural or forestry land. Therefore, it is necessary to test response of soils and plants and look for the most suitable combination of soil additive (biomass ash), and plants. Experimental part of PhD thesis was divided into the incubation experiment and the vegetation pot experiments. The incubation experiment: The efficiency of ash addition at two application rates was tested for nutrients enrichment in different soils within period of 56 days. The vegetation pot experiments: The two plants Triticum aestivum L: (three-year experiment) and Lolium perenne L. (one-year experiment) were planted in the 5L pots. Soils were treated with ash or ash combinated by superphoshate and flue gas desulfurization gypsum. For both plants, we evaluated the plant growth, biomass production and content of macro, micro and toxic elements in the biomass and in the soils.
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Doppler's sensor beat freqeuncy proccessing
Dušek, Martin ; Macho, Miloslav (referee) ; Fuchs, Michal (advisor)
This work is engaged in ways of objects speed measuring mainly helped by Doppler Effect. The sensor HB410 is described in this work and its possible elaboration output heterodyne analog signal. The calculation of objects speed is deduced from frequency of heterodyne signal. In this work is projected circuit solution for elaboration of analog signal and its digitalization. Available types and nature of microcontrollers which are elaborating digital signal and communicating with PC are summarized in this work. In the last chapter is described microcontroller's driving software and PC software for speed measure.
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