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Classifier of astrophysics data
Rylko, Vojtěch ; Vrábelová, Pavla (referee) ; Zendulka, Jaroslav (advisor)
Cílem této práce je implementace algoritmu pro dolování z dat pro použítí v astrofyzice. V práci jsou představeny základní pojmy a principy dolování z dat. Zejména jeho obecná definice, rozlišení mezi klasifikací a regresí a vyhodnocování přesnosti modelu. Text se zabývá převážně učením s učitelem. Blíže představeny jsou algoritmy založené na rozhodovacích stromech. Je definován rozhodovací strom jako model a uveden obecný algoritmus pro tvorbu rozhodovacích stromů z dat. Jsou diskutována různá kritéria dělení v uzlech (zejména založená na etropii), kritéria pro ukončení růstu a ořezávání stromů. Pro ilustraci jsou uvedeny vybrané algoritmy - ID3, CART, RainForest a BOAT. Na dříve uvedených informacích je založena kapitola o souborech rozhodovacích stromů. Zabývá se základními způsoby jejich kombinací (bagging a arcing) . Detailněji je popsán obecný algoritmus náhodných lesů a RandomForest TM jako příklad jeho praktické realizace. Na základě srovnání algoritmů a provedených experimentů v literatuře jsou k implementaci vybrány náhodné lesy. Implementovaný algoritmus je detailněji popsán - k dělení uzlů používá Gini entropie a průměrnou kvadratickou chybu, ignoruje chybějící hodnoty a pro kombinaci výstupů jednotlivých stromů používá většinové hlasování / průměr. Jako formát vstupních a výstupních dat je zvolena podmnožina ARFF formátu. Architektura implementace je ilustrována UML diagramy s popisujícím komentářem. Jednotlivé aspekty implementace jsou stručně popsány - implementačním jazykem je C++11, je využívána knihovna Boost (zejména chytré ukazatele, serializace, nastavení parametrů a konfigurační soubory, ...) společně s dalšími volně dostupnými knihovnami (google-glog pro logování, googletest pro jednotkové testování, ...). Grafického výstupu je dosaženo tiskem modelu náhodného lesu do XML souboru a jeho transformací skriptem do jazyka DOT. Pro oveření validity a vlastností implementace a jejího srovnání s jinými implementacemi náhodných stromů (Waffles, RF-ACE a R - balíček randomForest) jsou navrženy, popsány a provedeny exprimenty: klasifikace astronomických těles na základě barevných indexů, regrese rudého posuvu na základě barevných indexů, osm klasifikačních a pět regresních experimentů na datech z UCI repository. Průběh experimentů je plně automatizován skripty (Bash, Python a R) a je měřena doba učení modelů. Z výsledků experimentů vyplývá, že autorova implementace si vedla výborně při klasifikaci a průměrně při regresi; z časového hlediska měla problémy při datech s mnoha instancemi. Výsledkem práce je zdokumentovaná, snadno rozšiřitelná implementace náhodných lesů v jazyce C++ s grafickým znázorněním modelu, mnoha možnostmi nastavení a experimentálně ověřenou funkčností. Diskuze o dalším možném pokračování projektu se zabývá zejména odstraněním problemů s časovou náročností a přídáním nových funkcionalit.
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Concentration of parenteral preparations. Electrolytes.
Novotná, Jitka ; Šklubalová, Zdeňka (advisor) ; Šnejdrová, Eva (referee)
Amount of the dissolved substances in parenteral solutions is expressed in molarity (mol ∙ l-1 ). To express the osmotic effect of the dissolved particles in one litre of solution, osmolarity (mosmol ∙ l-1 ) is used. Physical measurement is provided by an osmometer. However, by this measurement we can determinate osmolality (mosmol ∙ kg-1 ) which depends on the concentration in molality (mol ∙ kg-1 ). Mutual conversion between osmolality and osmolarity is then desirable. The conversion of molality to molarity requires a knowledge of the volume of the solution whereas the conversion factor is wanted to convert molarity to molality. Conversion factor, in fact, expresses content of water in the solution. The mutual conversion between molality and molarity requires knowledge of the solution density. In this work, the effect of temperature in range of 15-40žC on density of the aqueous solutions was studied. Aqueous solutions of sodium chloride, potassium chloride and ammonium chloride in concentration range of 0,1 - 1,0 mol ∙ l-1 or 0,1 - 1,0 mol ∙ kg-1 were investigated. Relationship between the solution density and temperature was described with quadratic equation regressions. The solution density was directly proportional to the solution concentration at 20žC. Using the average density at 20žC, the...
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Econometric Analysis of Microeconomic Processes. Application on Wages in the Czech Republic
Kalčevová, Jana ; Pánková, Václava (advisor) ; Arlt, Josef (referee) ; Cahlík, Tomáš (referee)
This thesis is focused on wages models on the czech labor market in 1996 and 2002. Wages models are built on non-trivial mathematical background and parameters of given models are estimated by methods based on sum of squared residuals and also not often used quantile regression. The quantile regression theory is described in the thesis together with test statistics. Properties of estimations, demonstration examples and proposal of practical application are also indroduced. The theory was applied to two large-size data-files, recieved results show the difference between years 1996 and 2002; a comparison with European Union countries is also given.
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Patogenesis of aortic stenosis. Posibillity of medical treatment
Štěrbáková, Gabriela ; Linhartová, Kateřina (advisor) ; Rosolová, Hana (referee) ; Staněk, Vladimír (referee) ; Hricák, Vasiľ (referee)
Background: Calcific aortic stenosis is the most frequent and most frequently operated valvular diasease. Currently, there is no known medical treatment to slow the progression of the disease. The aim of our study was first, to assess predictors of the progression of the aortic valve calcification, and second, to assess the association of the progression of aortic stenosis with the bisphosphonate treatment. Methods: Part I - prospective follow-up of consecutive patients with coronary artery disease associated with aortic stenosis (mean transvalvular aortic gradient of 30 mmHg or greater), aortic sclerosis or normal aortic valve were prospectively identified. Clinical, laboratory, echocardographic, angiographic and calcium score evaluation using multidetector computer tomography at baseline, and at the end ofthe study. Predictor of calcification were sought using multivariate regression. Part II - pilot retrospective study of patients with aortic stenosis and two echocardiographies >8 months apart. The patients were divided into those treated with bisphosphonates for osteoporosis and those not treated. We compared the annualized gradient change between the groups and identified predictors of AS progression. Results: Part I 294 patients were prospectively enrolled, with mean follow-up 30±11 months....
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Determinants of claim occurrence: case of Motor Third Party Liability insurance
Novotný, Jakub ; Bolcha, Peter (advisor) ; Potužák, Pavel (referee)
In this paper the hypotheses related to individual variables used for segmentation of Motor Third Party Liability (MTPL) insurance by Czech insurance companies are tested. Summary of papers focused on this topic and development of insurance market segmentation in European Union are presented in the first part of this thesis. The first part of this paper is extended by the analysis of actual MTPL segmentation in Czech Republic. The estimation of marginal effects of exogenous variables on probability of occurrence a claim is described in empirical part. For the estimation of parameters I use the logistic regression. Specific models for small and large claims are created. The most significant variables positively correlated with probability of occurrence a claim are engine capacity, young age and region Prague. The most significant variables negatively correlated with probability of occurrence a claim are historical car, old age, number of months without any claim and region South Moravia. My results are compared to the results of other papers.
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Impact of overweight and obesity on life quality
Nová, Kateřina ; Rychtaříková, Jitka (advisor) ; Kraus, Jaroslav (referee)
This diploma thesis addresses overweight and obesity worldwide and in the Czech Republic. It deals primarily with child obesity and investigates obesity impact on life quality of individuals. The aim of this work was to manifest a negative effect of obesity and overweight on health of the population. The theoretic part of the thesis deals with obesity definition, methods of measurement, treatment options and time trends with an emphasis on the situation in the Czech Republic. Effects of overweight and obesity on humans are analysed on the basis of expert studies. The obesity increases mortality and morbidity levels and the risk may increase if the prevalence grows. The analytical part of the work deals with the examination of survey data for children and adults. Statistical methods of correlation and regression were used for the analytical purpose. Powered by TCPDF (www.tcpdf.org)
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Determination of soluble phenolics in common spruce stands using hyperspectral data
Buřičová, Michaela ; Kupková, Lucie (advisor) ; Petruchová, Jana (referee)
The thesis deals with lignin and soluble phenolic determination in Norway spruce foliace using hyperspectral data. A literature overview is focused on the analysis of lignin and soluble phenolics. The practical part focuses on the determination of wavelenghts intervals which are suitable for the detection of lignin and soluble phenolics. There is applied regression analysis for the determination of relationship between the foliage spectra and the content of biochemical substances for the chosen spektrum intervals. Indexes NDLI, mNDLI and RLI were than calculated. HyMap hyperspectral airborne images from 2009 and 2010 for the area of Sokolov, spectral curves of dry matter and fresh branches of Norway spruce and laboratory determination of lignin and soluble phenolics content were the inputs for the analyses. Maps of lignin content in Norway spruce are the final output of the work. Keywords: Norway spruce (Picea Abies), lignin, soluble phenolics, PLS (partial least square) method, multiple Stepwise regression, NDLI
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Influence of sports on smoking and consumption of alcohol
Michlian, Štefan ; Princ, Michael (advisor) ; Hrbek, Pavel (referee)
This paper focuses on the meaning of sport for present people. All motivations which lead them to practise sport are stated. We consider the trend of decreasing volume of physical activity in population especially in developed countries and the total social costs because of this trend. We analyse the investments opportunities of health system in promoting physical activity and how much these methods are cost-effective. Furthemore the meaning of sport as prevention before socially undesirable phenomena is examined, particularly smoking of cigarettes and consumption of alcohol We present the previous studies which were done in this topic. The methodology of survey, questionnaire survey in theory and in practice is described. In the last chapter gained data are analysed with OLS method, Tobit model, probit model and interval regression. Pros and cons of these models and results are commented.
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Analysis of Occurrence of Imported Infectious Diseases in the Region of South Bohemia over the Last Five Years
MYSLÍK, Ladislav
Imported diseases are infections that have been acquired during a travel or a stay abroad. Such infectious diseases may include cosmopolitan and potential re-introduction illnesses and tropical and re-emerging illnesses. The movement of populations affects the distribution and spread of communicable diseases globally. Today?s mobility and unnatural interaction of different races or otherwise geographically defined populations facilitate the emergence of contagious diseases in humans, animals or, even in plants. Some pathogens can be imported into a new area by travellers or immigrants in the absence of illness signs or symptoms. Many geographical barriers have now been breached by mobility and migration. The theoretical section of this thesis is mainly aimed to provide a description of the most common imported diseases according to their current epidemiological trends. Travel-related risks, risk groups of travellers and migration characteristics are also mentioned. In addition, it deals with domestic and international inbound and outbound tourism and includes a forecast of international tourism development towards 2030. The conclusion of the theoretical section aims to describe epidemiology of imported diseases and to provide an insight into systems of monitoring and surveillance of travel-related infections, such as GeoSentinel Surveillance Network, EuroTravNet, TropNet and the Czech Nationwide Epidat information system. The objective of this diploma thesis of the empirical section is to carry out an analysis of occurrence of imported infectious diseases in the Region of South Bohemia over the last five years. Data and information recorded into Epidat database from 2007 to 2011 shapes the target group. Methods of research are mainly based on descriptive statistics that describe most of collected data quantitatively. Moreover, seven hypotheses were designed that were tested via results using regression analysis, Pearson's chi-squared test and Student's t-test. A total of 190 cases from 46 world-wide destinations were imported between 2007 and 2011. Of those, 166 were imported by residents; 24 cases were brought in by foreigners. The most frequent countries of acquisition were European destinations (49%; n = 92), Asia (33%; n = 63) and Africa (16%; n = 31). Gastro-intestinal (GI) diseases accounted for 68.4% of illnesses, followed by blood-borne and vector-borne infections. GI conditions included campylobacteriosis (n = 38), salmonellosis (n = 33) and shigellosis (n = 30). Amongst blood-borne diseases, hepatitis B accounted for 21 cases (mainly in Vietnamese). Amongst vector-borne illnesses, 6 cases of malaria and 1 case of dengue were identified. Hypothesis H1 (further described only as H2, etcetera) "There is an association between numbers of travellers and occurrence of imported infectious diseases" was rejected. H2 "There is a different incidence rate among countries of acquisition" could not be confirmed because of the lack of the denominator data (numbers of travellers to specific destinations). H3 "The most frequent countries of acquisition are European countries" was confirmed and accepted. H4 "The highest rate of imported infectious diseases is in the České Budějovice District" was confirmed and accepted. H5 "The most frequent imported infections are gastro-intestinal diseases" was confirmed and accepted. H6 "There is a descending tendency of occurrence of imported infectious diseases" was rejected. H7 "There is a higher likelihood of presenting with a vaccination preventable disease in unvaccinated returned travellers" could not be confirmed due to the lack of data.
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