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Durability of Polyehtylene Ribbons from Netwrap
Huljak, Pavel ; Poláček, Petr (referee) ; Bálková, Radka (advisor)
This diploma thesis deals with the measurement of mechanical properties and accelerated aging of monoaxially stretched polyethylene strips coming from three types of polymeric mesh, which serves to pack hay on baling machines. The strength of the strips is evaluated from two points of view. The first one is static tensile strength measured before and after accelerated aging at 23 °C and 40 °C, the second one determines the strength as the weight that causes the strip failure on a simple machine at 23, 40, 60 and 80 ° C. The results show that the smallest static strength has the least stabilized strip, which, on the other hand, revealed the highest strength in a dynamic loading. The change of supermolecular structure was evaluated by calorimetric measurements. The data shown only very little change of inner structure due to the average response of the whole crystalline phase comprising relatively wide distribution of crystallites. It is more than probable that supermolecular structure had been changed but the method is not sensitive to see the change of orientation of lamellae and macromolecular chains in them.
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Study of chemical processes in Titan atmosphere
Klohnová, Karolína ; Grossmannová, Hana (referee) ; Krčma, František (advisor)
The bachelor’s thesis deals with study of chemical processes in Titan atmosphere simulated under laboratory conditions. The abnormal glow discharge as a for-step for gliding arc discharge was used for the plasma generation in nitrogen-methane gas mixture corresponding to the Titan atmosphere composition. The optical emission spectroscopy was chosen as the basic plasma diagnostic method. The theoretic part of thesis describes briefly history of Titan atmosphere studies including the last space craft obtained results. Later, the fundamental properties of plasmas including their diagnostics are given. The general components determined in Titan atmosphere include N2, CH4, H2 molecules as well as a suite of lower weight hydrocarbons including HCN, C2H2 and C2H4; some traces of higher hydrocarbons and amino acids were determined, too. The electrode configuration corresponding to gliding arc arrangement with interelectrode gap of 2 mm was used with high voltage power supply giving power up to 300 W. Plasma was generated in the nitrogen-methane mixtures (0.5 – 2.5 % of methane) at atmospheric pressure. Both gases had purity better than 99.999% and all system was evacuated before measurement to suppress oxygen traces. Optical emission spectra were taken in dependence of applied power and gas mixture composition. Nitrogen and CN radical spectra as well as atomic lines of hydrogen and carbon were identified in the spectra. The vibrational temperatures of 2300 - 8000 K were determined from the spectra of nitrogen second positive, CN violet and C2 spectral systems. Rotational temperature calculated from nitrogen second positive and CN violet 0-0 bands varied in the interval of 1200 - 4800 K depending on the experimental conditions. The obtained results were submitted as a part of paper into international journal. The obtained results maybe used as a fundament for the future study of Titan atmosphere using also other discharge.
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Effect of nutrients deficiencies on root architecture and growth of winter wheat
Rattanapichai, W. ; Klem, Karel
The study of the effects of N, P, K deficiencies on root architecture and growth was tested in phenotyping platform with winter wheat (Bohemia variety). The experiment was arranged with 4 treatments: Complete nutrient, Without N, Without P and Without K. The root were grown on the surface of vertically fixed black filter paper sheets (30x60cm), covered from both sides by black plastic sheets (PVC-P). The system was setup with a micro-irrigation channel in the top of sheets to ensure circulation of hydroponic medium as hydroponic system. Eighteen days after transplanting, we took the root images by the standard RGB digital camera. To evaluate the root architecture parameters the "SmartRoot" software was used. The results showed that nutrient deficiency had effect on root architecture of winter wheat. N deficiency increase in total seminal root and lateral root length and root/shoot ratio, while P deficiency resulted in increase of mean root diameter, total root area when compared to the control. N deficiency also decreased root and shoot dry weight and total leaf area. However, nutrient deficiency slightly decreased lateral density. There was a slight effect of K deficiency on root architecture when compared to the complete nutrient application. The increasing of leaf dry weight was related with the increased of root dry weight.
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DEVELOPMENT OF ICHTIOFAUNA IN THE NEW FILED POND CHABAŘOVICE
ŤUK, Josef
The Chabarovice coal mining pit arose by flooding the former strip mine area for brown coal. After filling, the pit area should reach about 225 hectare, total volume of water 34.4 mil. m3, average depth 15,6 meters with maximum of 23,3meters. It is assumed that the pond and adjacent areas will be used for recreation usage after completion of recultivation and ground shaping. I have performed the investigations in June and in August 2004 - 2005, using basic ichthyological methods. The data about recruitment were collected by the littoral seine net and adult fish (older than one year) were investigated by gillnets nets. Fish was determinated to genus, individually measured by slide caliper (fry) and by measuring plate (adult fish). The lenght of fish body (SL-standart lenght) was measured in millimeters and fish were weighted separately (W v g). In the year 2005, also scales were taken from individual fish for the age assesment. Obtained data were processed with regard to performed biomanipulation measures in individual sectores. Nine fish species and one hybrid were recorded by the monitoring with gillnets nets. The most numerous fish were juveniles and adults of rudd with SL 74 {--} 300 mm and the weight up to 618 g. The fish species with the strongest impact upon the pit ecosystem function is conitnuously the perch with the dominance of individuals with SL 46 to 337 mm and weight zup to 850 g.
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Study of factors influencing weight of oral drops
Franzová, Pavla ; Šklubalová, Zdeňka (advisor) ; Řehula, Milan (referee)
10 SUMMARY The factors influencing weight of peroral drops were investigated in this dissertation. During this work six commercial available plastic dropper tips for peroral drops and model mixtures of hydrophil solvents were used. It was determined that the most suitable mixture for testing dropper charakteristics (depending on design of dropper tip) was the mixture of five parts of 96% ethanol and ninetyfive parts of purified water or the mixtureof sixty parts of 85% glycerol and forty parts of purified water. The weight of drop was influenced by the diameter of outer orifice of dropper tip. The final weight of drop is also affected by the other charakteristics - inner diameter of dropper part, inner aperture diameter of dropper capilary, design of dropper tip, design of compensatory capilary. The drop weight of mixture of water with glycerol increased with decreasing density of mixture. The reduction of dropper angle from 90ř (vertical) to 45ř (transversal) lead to decisive reduction of drop weight. The uncontrolled wettion of dropper surface by the liquid was observed in some cases. On the base of optimal dispending of peroral drops we should recommend the producer following: there should be the instruction about the right holding of dropper bottle in upright position (upside-down, 90ř vertical)
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Webmining
Ljubopytnov, Vladimír ; Húsek, Dušan (referee) ; Pokorný, Jaroslav (advisor)
This thesis focuses on mapping latest knowledge in the area of web mining with emphasis on document clustering. Most attention is given to the DOC projective clustering algorithm, a modification is presented for data with weighted dimensions. Algorithm is used for web search engine result clustering. Also, a clustering package with Google interface and phrase evaluation tool is implemented.
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Sociomap Visualization
Höschl, Cyril ; Černý, Jakub (referee) ; Bálek, Martin (advisor)
In this work we study algorithms for visualization of sociomaps. We focus on surface-fitting method which converts bitmap picture into a sequence of closed spline curves. For curve-fitting, we describe tracing algorithm that for a given level of height in a smooth surface finds a contour as a closed Bézier curve. Further we describe algorithm that draws hierarchy of clusters into a 2D plane. We first create a skeleton of the cluster analysis which we then project into a plane using curve-fitting method. We describe methods of interpolation of surface based on inverse distances weights and also we present a linear interpolation based on Delanauy triangulation. We apply these methods on sociomappig analysis. Sociomapping is a data-mining method for visualization of relations among objects as well as analyzing statistical data. The result of sociomapping analysis is an easy-to-read picture - a sociomap. We explain cluster analysis for model of a sociomap and also we describe statistical test based on fuzzy approach.
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Minimum Weight Triangulation (MWT)
Charvát, Pavel ; Kolingerová, Ivana (advisor) ; Ferko, Andrej (referee)
For a long time, it has been neither known whether MWT is solvable in a polynomial time nor whether it belongs to NP. As we now, its status still remain unknown. We present severalknown approaches to MWT such as modifications of the problem with known time complexity or various heuristics and approximations which allow us to find an exact or at least an approximate solution in a reasonable time. We compare the approximations in some particular situations. The main part of the work is devoted to a description and implementation of an efficient heuristic with (almost?) linear expected complexity for points uniformly distributed in some convex shape. The algorithm is a modification of Drysdale's algorithm for finding GT candidates and Beurouti's computation of the modified LMT-skeleton, where we add some proofs of the correctness. We are able to complete MWT from the graph of candidate edges in O(n · d3 + n · d2+k), where d is the the maximum degree and k is the maximum number of inner components of some skeleton face. Further, we suggest a new approximation of MWT with polynomial complexity in the worst case and (almost?) linear expected complexity, which only rarely differs from the optimal triangulation and has O(1) approximation factor in the worst case. This approximation combines the LMT-skeleton...
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Food of predatory fish during the flooding of the Chabařovice coal mining pit
KABILKA, Petr
The Chabařovice coal mining pit is currently still under the process of continuous flooding and its area increased up to 174 ha since 2001.Adult perch (Perca fluviatilis) have been the most numerous fish of the lake until 2004. Fish were collected during the ichtyological survey sampling campaigns in June and September.Diet composition was expressed as percent weight, which was calculated for each prey taxon.
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Possibilities of UCP2 (uncoupling protein 2) induction in rat hepatocytes in in vivo conditions
Bolehovská, Radka ; Červinková, Zuzana (advisor) ; Kalous, Martin (referee) ; Novotný, Dalibor (referee)
Possibilities of UCP2 (uncoupling protein 2) induction in rat hepatocytes in in vivo conditions Introduction Uncoupling protein 2, discovered in 1997, is the first described homologue of uncoupling protein 1. Uncoupling proteins increase the permeability of inner mitochondrial membrane for protons, decrease the efficiency of energy conversion, inhibit the ATP synthesis and stimulate energy release in form of heat. Uncoupling proteins also increase the substrate oxidation and reduce production of reactive oxygen species in mitochondria. Objective, material and method The aim of this study was to establish and optimised the quntitative real-time PCR for detection of UCP2 mRNA expression kinetics in rat liver tissue. The present study was conducted to assess the effects of acute and chronic treatment with triiodothyronine and the effect of partial hepatectomy on liver uncoupling protein 2 mRNA levels in male Wistar rats. Results Intraperitoneal injection of one dose of triiodothyronine (200 μg/kg rat body weight) increased mRNA expression of uncoupling protein 2 in liver tissue almost 2-fold (P < 0.01 vs. control group) in rats 12 hours after T3 administration. Concentrations of total triiodothyronine and free triiodothyronine in serum were increased 122-fold and 77-fold (p < 0.001), respectively....
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