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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.
171

Návrh a implementace Data Mining modelu v technologii MS SQL Server / Design and implementation of Data Mining model with MS SQL Server technology

Peroutka, Lukáš January 2012 (has links)
This thesis focuses on design and implementation of a data mining solution with real-world data. The task is analysed, processed and its results evaluated. The mined data set contains study records of students from University of Economics, Prague (VŠE) over the course of past three years. First part of the thesis focuses on theory of data mining, definition of the term, history and development of this particular field. Current best practices and meth-odology are described, as well as methods for determining the quality of data and methods for data pre-processing ahead of the actual data mining task. The most common data mining techniques are introduced, including their basic concepts, advantages and disadvantages. The theoretical basis is then used to implement a concrete data mining solution with educational data. The source data set is described, analysed and some of the data are chosen as input for created models. The solution is based on MS SQL Server data mining platform and it's goal is to find, describe and analyse potential as-sociations and dependencies in data. Results of respective models are evaluated, including their potential added value. Also mentioned are possible extensions and suggestions for further development of the solution.
172

Diskriminační a shluková analýza jako nástroj klasifikace objektů / Discriminant and cluster analysis as a tool for classification of objects

Rynešová, Pavlína January 2015 (has links)
Cluster and discriminant analysis belong to basic classification methods. Using cluster analysis can be a disordered group of objects organized into several internally homogeneous classes or clusters. Discriminant analysis creates knowledge based on the jurisdiction of existing classes classification rule, which can be then used for classifying units with an unknown group membership. The aim of this thesis is a comparison of discriminant analysis and different methods of cluster analysis. To reflect the distances between objects within each cluster, squeared Euclidean and Mahalanobis distances are used. In total, there are 28 datasets analyzed in this thesis. In case of leaving correlated variables in the set and applying squared Euclidean distance, Ward´s method classified objects into clusters the most successfully (42,0 %). After changing metrics on the Mahalanobis distance, the most successful method has become the furthest neighbor method (37,5 %). After removing highly correlated variables and applying methods with Euclidean metric, Ward´s method was again the most successful in classification of objects (42,0%). From the result implies that cluster analysis is more precise when excluding correlated variables than when leaving them in a dataset. The average result of discriminant analysis for data with correlated variables and also without correlated variables is 88,7 %.
173

Similarity Measures for Nominal Data in Hierarchical Clustering / Míry podobnosti pro nominální data v hierarchickém shlukování

Šulc, Zdeněk January 2013 (has links)
This dissertation thesis deals with similarity measures for nominal data in hierarchical clustering, which can cope with variables with more than two categories, and which aspire to replace the simple matching approach standardly used in this area. These similarity measures take into account additional characteristics of a dataset, such as frequency distribution of categories or number of categories of a given variable. The thesis recognizes three main aims. The first one is an examination and clustering performance evaluation of selected similarity measures for nominal data in hierarchical clustering of objects and variables. To achieve this goal, four experiments dealing both with the object and variable clustering were performed. They examine the clustering quality of the examined similarity measures for nominal data in comparison with the commonly used similarity measures using a binary transformation, and moreover, with several alternative methods for nominal data clustering. The comparison and evaluation are performed on real and generated datasets. Outputs of these experiments lead to knowledge, which similarity measures can generally be used, which ones perform well in a particular situation, and which ones are not recommended to use for an object or variable clustering. The second aim is to propose a theory-based similarity measure, evaluate its properties, and compare it with the other examined similarity measures. Based on this aim, two novel similarity measures, Variable Entropy and Variable Mutability are proposed; especially, the former one performs very well in datasets with a lower number of variables. The third aim of this thesis is to provide a convenient software implementation based on the examined similarity measures for nominal data, which covers the whole clustering process from a computation of a proximity matrix to evaluation of resulting clusters. This goal was also achieved by creating the nomclust package for the software R, which covers this issue, and which is freely available.
174

Shluková a regresní analýza mikropanelových dat / Clustering and regression analysis of micro panel data

Sobíšek, Lukáš January 2010 (has links)
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.
175

European Electricity Market and EU Members'Energy Policies / Evropský trh s elektřinou a energetické politiky států EU

Veselý, Aleš January 2012 (has links)
The main focus of this thesis is to find out what factors have the biggest influence on the price of electricity for household consumers in the European Union in the context of creating the internal electricity market in the EU. By means of the cluster analysis six EU Member States have been selected according to the following criteria: electricity consumption, electricity production, and the price of electricity. As a result of that Belgium, the Czech Republic, Estonia, Hungary, Malta and Sweden have been selected. Consequently, the regression analysis has been carried out to find out what factors influence the electricity prices in every country individually. The independent variables are mainly various sources of electricity production. It was found out those renewable resources most influent the electricity price for households in Belgium, Estonia, Hungary, and Sweden. Nevertheless, in the context of Europe 2020 strategy and the formation of the European energy market, one of the European Commission's objectives is to increase the share of renewable sources in the production of electricity in the EU Member States. Therefore, it will bring about higher prices of electricity, which goes against the Commission's effort to decrease the price of electricity for households through the liberalisation of electricity and the creation of the internal electricity market.
176

Marketingová doporučení pro porodnice na základě dotazníkového šetření zkoumajícího preference rodiček / Marketing recommendations for maternity hospitals on the basis of questionnaires inquiry containing preferences of expectant mothers

Kuželová, Adéla January 2012 (has links)
The main goal of this Master's Thesis is to form marketing recommendations for maternity hospitals. These marketing recommendations are in the form of marketing mixes, that are designed for individual revealed segments. The theoretical part of my Master's Thesis contains the reason why the maternity hospitals should implement marketing in the present day. Further goal of the theoretical part is to explain why I apply to the area of obstetrics the marketing of services. Further the theoretical part describes specifics of marketing of services, segmentation process, targeting and positioning. There is stated characteristics of the marketing mix in the area of services at the end of the theoretical part. The analytical part is based on written questionnaires inquiry. On the basis of results of questionnaires inquiry is carried out the process of segmentation using statistical programme IBM SPSS Statistics version 21.0. The result of segmentation process is discovering three market segments. These segments show similar characteristics. There is determined attractiveness of revealed segments in the chapter dealing with targeting. Marketing recommendations describe the value of providing services. Marketing recommendations are supplemented with social status of respondents.
177

Analýza AVG signálů / Analysis of AVG signals

Musil, Václav January 2008 (has links)
The presented thesis discusses the basic analysis methods of arteriovelocitograms. The core of this work rests in classification of signals and contribution to possibilities of noninvasive diagnostic methods for evaluation patients with peripheral ischemic occlusive arterial disease. The classification employs multivariate statistical methods and principles of neural networks. The data processing works with an angiographic verified set of arteriovelocitogram dates. The digital subtraction angiography classified them into 3 separable classes in dependence on degree of vascular stenosis. Classification AVG signals are represented in the program by the 6 parameters that are measured on 3 different places on each patient’s leg. Evaluation of disease appeared to be a comprehensive approach at signals acquired from whole patient’s leg. The sensitivity of clustering method compared with angiography is between 82.75 % and 90.90 %, specificity between 80.66 % and 88.88 %. Using neural networks sensitivity is in range of 79.06 % and 96.87 %, specificity is in range of 73.07 % and 91.30 %.
178

Shluková analýza signálu EKG / ECG Cluster Analysis

Pospíšil, David January 2013 (has links)
This diploma thesis deals with the use of some methods of cluster analysis on the ECG signal in order to sort QRS complexes according to their morphology to normal and abnormal. It is used agglomerative hierarchical clustering and non-hierarchical method K – Means for which an application in Mathworks MATLAB programming equipment was developed. The first part deals with the theory of the ECG signal and cluster analysis, and then the second is the design, implementation and evaluation of the results of the usage of developed software on the ECG signal for the automatic division of QRS complexes into clusters.
179

Borcení časové osy v oblasti biosignálů / Dynamic Time Warping in Biosignal Processing

Kubát, Milan January 2014 (has links)
This work is dedicated to dynamic time warping in biosignal processing, especially it´s application for ECG signals. On the beginning the theoretical notes about cardiography are summarized. Then, the DTW analysis follows along with conditions and demands assessments for it’s successful application. Next, several variants and application possibilities are described. The practical part covers the design of this method, the outputs comprehension, settings optimization and realization of methods related with DTW
180

Identifikace podobných řešení při stochastické simulaci v oblasti odpadového hospodářství / Similar solution identification in the field of stochastic simulation related to waste management

Gal, Pavel January 2015 (has links)
The Master’s thesis deals with the issue of collecting mixed municipal waste from producers to a~waste-to-energy or landfills. The initial chapters are aimed to waste legislation and transportation of the waste by road freight transport across Europe. The objective is to collect the data, that are required for calculation in tool NERUDA. The next part describes the cluster analysis and different approaches in it. The selected methods of cluster analysis are apllied to the logistic task in the final chapters. The cluster analysis is considered from different aspects. The results are visualized using the software ArcGIS.

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