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Network-wide Security Analysis
de Silva, Hidda Marakkala Gayan Ruchika ; Šafařík,, Jiří (referee) ; Šlapal, Josef (referee) ; Švéda, Miroslav (advisor)
Práce představuje model a metody analýzy vlasností komunikace v počítačových sítích. Model dosažitelnosti koncových prvků v IP sítích je vytvořen na základě konfigurace a síťové topologie a umožňuje ukázat, že vabraný koncový uzel je dosažitelný v dané síťové konfiguraci a stavu. Prezentovaná práce se skládá ze dvou částí. První část se věnuje modelování sítí, chování směrovaích protokolů a síťové konfiguraci. V rámci modelu sítě byla vytvořena modifikovaná topologická tabulka (MTT), která slouží pro agregaci síťových stavů určených pro následnou analýzu. Pro analýzu byl použit přístup založený na logickém programování, kdy model sítě je převeden do Datalog popisu a vlastnosti jsou ověřovány kladením dotazů nad logickou databází. Přínosy práce spočívají v definici grafu síťových filtrů, modifikované topologické tabulce, redukce stavového prostoru agrgací síťových stavů, modelů aktivního síťového prvku jako filter-transformace komponenty a metoda pro analýzu dosažitelnosti založena na logickém programování a databázích.
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Analysis and Testing of Concurrent Programs
Letko, Zdeněk ; Lourenco, Joao (referee) ; Sekanina, Lukáš (referee) ; Vojnar, Tomáš (advisor)
V disertační práci je nejprve uvedena taxonomie chyb v souběžném zpracování dat a přehled technik pro jejich dynamickou detekci. Následně jsou navrženy nové metriky pro měření synchronizace a souběžného chování programů společně s metodologií jejich odvozování. Tyto techniky se zejména uplatní v testování využívajícím techniky prohledávání prostoru a v saturačním testování. Práce dále představuje novou heuristiku vkládání šumu, jejímž cílem je maximalizace proložení instrukcí pozorovaných během testování. Tato heuristika je porovnána s již existujícími heuristikami na několika testech. Výsledky ukazují, že nová heuristika překonává ty existující v určitých případech. Nakonec práce představuje inovativní aplikaci stochastických optimalizačních algoritmů v procesu testování vícevláknových aplikací. Principem metody je hledání vhodných kombinací parametrů testů a metod vkládání šumu. Tato metoda byla prototypově implementována a otestována na množině testovacích příkladů. Výsledky ukazují, že metoda má potenciál vyznamně vylepšit testování vícevláknových programů.
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Intraday Dynamics of Euro Area Sovereign Credit Risk Contagion
Komárek, Luboš ; Ters, Kristyna ; Urban, Jörg
We examine the role of the CDS and bond markets during and before the recent euro area sovereign debt crisis as transmission channels for credit risk contagion between sovereign entities. We analyse an intraday dataset for GIIPS countries as well as Germany, France and central European countries. Our findings suggest that, prior to the crisis, the CDS and bond markets were similarly important in the transmission of financial shock contagion, but that the importance of the bond market waned during the crisis. We find flight-to-safety effects during the crisis in the German bond market that are not present in the pre-crisis sample. Our estimated sovereign risk contagion was greater during the crisis, with an average timeline of one to two hours in GIIPS countries. By using an exogenous macroeconomic news shock, we can show that, during the crisis period, increased credit risk was not related to economic fundamentals. Further, we find that central European countries were not affected by sovereign credit risk contagion, independent of their debt level and currency.
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Distribution of CD46 and β1 integrin molecules with respect to different membrane structures of the sperm head
Šebková, Nataša ; Frolíková, Michaela ; Děd, Lukáš ; Dvořáková-Hortová, Kateřina
CD46 protein plays an important role during fertilization and its role is associated with acrosome stability. CD46 is probably involved in signalling pathways triggering the acrosome reaction (AR). It also associates through membrane integrins with specific MAP kinases involved in the AR. Our aim was to monitor the dynamics of relocation of CD46 and β1 integrin during sperm maturation and its preparation for the fertilization. The dependence of this localization changes on the dynamic of actin cytoskeleton was studied. Our results show the changes in the localization of these proteins associated with the AR and their co-localization was observed using proximity ligation assay. After the AR CD46 and β1 integrin spreads across the sperm head, entering the post-acrosomal compartment, and permeates the borders of different domains. It was shown previously that actin dynamics is necessary for acrosome reaction-associated translocation of Izumo1 protein that is required for sperm-egg fusion. Therefore Latrunculin A was used during sperm incubation. The co-incubation of capacitated sperm with Latrunculin A leads to a decrease of the percentages of sperm, which express relocation pattern after induced AR. 3D models and visualizations of potential membrane processes responsible for the relocation of proteins from the acrosomal area to the other compartments of the sperm head were prepared. Our results deliver new information that proteins CD46 and β1 integrin undergo dynamic relocation towards the sites of sperm-egg fusion during the AR in vitro. The inhibitor of actin dynamics abrogates significantly the AR-associated changes in proteins localization. We speculate that this relocation is of importance for the successful sperm-egg interaction, adhesion and subsequent gamete fusion.
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Unreliability in Narration
HAVLOVÁ, Zuzana
The bachelor thesis is primarily focused on the aspects of unreliable narration in literature and deals with its characterization and assessment. It presents several theoretical expositions of unreliability accompanied by the analysis of the chosen literary illustrations demonstrating the discussed issues on the concerete samples. The indidvidual insights display that unreliability in naration is marked with disunity of opinion and a number of different attitudes. These facts result in substantially diverse interpretations of the particular literary works when apllying different criteria connected with distinct scholarly approaches. Simultaneously, the discrepancy of estimations and the thesis in general reflect dynamics, attractiveness and variety of this narratological category.
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The effect of pyrethroid based pesticides on fish
RICHTEROVÁ, Zuzana
Pyrethroids are ones of the most used pesticides worldwides. The widespread use and high stability of pyrethroids lead to the assumption of that their occurrence in the environment could be quite frequent. They can reach water ecosystem as pollutants. Residues of pyrethroids are not only detected in the water column, but also in sediments and in fish tissues. The first study was devoted to the product Nexide containing 60 g.l-1 of active substance gamma-cyhalothrin. Tested Nexide concentrations were 5, 25, 50, 100, and 250 µg.l-1. Early life stage test was used.Common carp (Cyprinus carpio) was tested. There were significant mortalities in all concentrations except the lowest concentration during the trial. The lowest concentration tested 5 µg.l-1 only caused a slightly increased mortality. This lowest concentration influenced the growth in length and weight negatively, decelerated ontogenetic development, and made the body surface of the individuals darker. Histopathology of individuals from this concentration revealed dystrophy in liver. Examination of kidney, intestine and gills did not show significant histopathological differences compared with control. The evaluation of selected parameters of oxidative stress demonstrated a significantly higher activity of detoxification enzyme glutathione-S.transferase (GST) and a significantly lower activity of defensive enzyme glutathione peroxidase (GPx) compared with the control group. The other examined parameters of oxidative stress such as catalase (CAT), glutation reductase (GR), and lipid peroxidation determined by using the thiobarbituric acid-reactive substances (TBARs) were comparable to the control group. Changes in oxidative stress parameters suggest that exposure of the organism to the product Nexide in the given concentration leads to dysbalance of defensive enzymes. The second study was devoted to the product Cyperkill 25 EC containing 250 g.l-1. Tested Cyperkill 25 EC concentrations were 7.2, 36, 72, 144, and 360 µg.l-1. The procedure of the trial was the same as the preceded one. There were 100% mortalities in all concentrations except the lowest concentration during the trial. The lowest tested concentration 7.2 µg.l-1 allowed 90% of individuals to stay alive till the end of experiment. The lowest concentration influenced the growth in length and weight negatively and decelerated ontogenetic development compared with the control. Any individual exposed to this concentration did not reach juvenile stage until the end of the trial. Dark pigmentation was visible in 68% of these exposed individuals on the last day. Similar darkening was visible in individuals from higher concentrations shortly before death too. Histological examination did not revealed significant changes in intestine, liver, kidney, and gills compared with the control group. Evaluation of selected parameters of oxidative stress demonstrated significantly lower activities of GST, GR, and GPx. Activities of CAT and TBARS were comparable with the control group. Changes in oxidative stress parameters suggest that exposure of the organism to the product Cyperkill 25 EC in the given concentration could induce oxidative stress and interfere with the activities of antioxidant enzymes. The presented thesis summarises actual data about pyrethroids and their influence on fish. The demonstrated effects confirm high susceptibility of early developmental stages of fish to tested pesticides. When interpreting the results, we have to take into account the fact that studies showed this risk even on single pyrethroid substances. But water organisms are exposed to many other more or less toxic products and substances in a real environment. These xenobiotics could react with each other and their mixture could even potentiate negative effects. The performed studies also clearly show the significant differences in the sensitivity of embryonic and embryolarval tests.
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Optimization of microclimate parameters in dairy farms, while reducing the energy consumption of selected technological systems
Češpiva, Miroslav ; Pecen, Josef (advisor) ; Ján, Ján (referee)
Thesis is focused on the measurement and evaluation of microclimate parameters in barns for dairy farming and the determination of the energy consumptions of selected technologies in these barns. The aim of this work was to design and eventually to implement adjustments in order to improve the parameters of cowshed microclimate and reducing the energy consumption of selected technologies in depends on results of the measurements. Three structurally different cowsheds with different slurry clearing technologies were selected for monitoring. I focused on the measurement of temperature and relative humidity in relation to temperature- humidity index and its impact on heat stress on dairy cows. I measured airflow in the cowsheds and I determinate concentrations and emissions of ammonia and methane in the cowsheds in different seasons. I monitored light intensity in the cowsheds and I determined the dependence of building solutions on the use of outdoor light to illuminate the interior of the barns. The energy consumption of the lighting system depending on the season and the consumption of additional fans on the air temperature were studied.
On the bases of results of the experimental part I designed and implemented lighting system, controlled by light intensity in a cowshed and energy-saving ventilation in the cowshed - type K105. I suggested a system of continuously monitoring of climatic parameters in the cowshed with immediate calculation of temperature- humidity index.
Measurements have shown the dependence of gases concentrations on the way of slurry clearing technologies. The building solutions of cowsheds and type of ventilation proved a significant influence on the temperature- humidity index during the summer.
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Growth and environmental effects of Grand fir cultivation in conditions of the Czech republic
Fulín, Martin ; Podrázský, Vilém (advisor) ; Antonín, Antonín (referee)
Grand fir (Abies grandis /Douglas ex D. Don/ Lindl.) is a species with potential benefits for the implementation of many functions in forest management: namely the function of production, soil improvement, stabilization and landscaping. It was introduced to the Czech Republic, as well as to other European countries, since the first half of the 19th century, mainly by aristocratic families. First plantings were performed in the parks, but gradually also in the forest stands. Another wave of interest in this tree species was associated with the decline of the domestic silver fir (Abies alba Mill.). It was to some extent substitute, for this period comes the greatest number of plantations in the country. The aim of this thesis is, therefore, monitoring of growth and production of the grand fir, but also the evaluation of the effects on the basic characteristics of the soil chemistry, nutrient dynamics and possible degradation effect on forest lands. Research areas were mainly located in the University Forest Enterprise Kostelec nad Černými lesy, but also in other places such as Hrubá Skála at Turnov, forests owned by Kinský at Žďár nad Sázavou and Kynšperk nad Ohří. Monitoring was carried out on already established and monitored middle-aged permanent plots (35 to 55 years), which were assessed at mensurational parameters (position, height, diameter at breast height, ratio of the green crown), in further the quantity and quality of forest floor and upper mineral soil components was studied. This work also contains the measurements of the provenance plot of Forestry and Game Management Research Institute. The results show that the grand fir is a productive tree species that exceeds the stock of domestic conifer tree species and its intensive growth is comparable with Douglas fir. From the perspective of provenance trials is crucial the correct choice of provenance, which achieves better yields and quality of wood. Best provenances come from the island Vancouver and the coast of Washington state. At the soil analysis reaching grand fir better values in comparison with Norway spruce and got it closer to the values of broad-leaved tree species. Thus it can be said that grand fir represents important soil-improving and stabilization tree species.
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Utilization of biological and chemical amelioration treatments for restoration of anthropogenic degraded locality near Boleboř village in Ore Mts.
Kouba, Martin ; Podrázský, Vilém (advisor)
This dissertation contains evaluation of the growth dynamics and nutritional status of tree species plantations after application of biological and chemical amelioration treatments, impact of trees on quality of soil and on the accumulation of surface humus. There were evaluated: Norway spruce (Picea abies L.), Blue spruce (Picea pungens Engelm.), Birch (Betula spp.), European larch (Larix decidua Mill.), Gray alder (Alnus incana Moench.), Lodgepole pine (Pinus contorta Dougl.), Eastern White pine (Pinus strobus L.) and Rowan (Sorbus aucuparia L.).
On 4 research plots in Boleboř (Ore Mts.) was measured height, thickness of root collar, breast-height diameter. Were taken samples of soil, weed and assimilation apparatus. There was determined yellowing, browsing, plants mortality and calculated amount of accumulated surface humus.
Application of fertilizer Silvamix Forte on spreading windrows reduced mortality and increased increment for the first 3 years, the effect is evident even after 10 years. It was not confirmed the attractiveness of plants for wildlife after Silvamix Forte application. Silvamix Mg fertilizer application had minimal effect on the growth dynamics and nutrient contents in needles. Positively impacted soil characteristics, increased the value of the cation exchange capacity, decrease in hydrolytic acidity, increase the saturation of sorption bases, decrease of aluminium ions Al3+ and decrease of Fe2O3. On fertilized plots increased content of available nitrogen, phosphorus, calcium and magnesium, increase of the total supply of nitrogen, calcium and magnesium. The rapid increase in the content of Ca and Mg is related to the liming in 2002. Fertilizer application significantly supported the development of ground-weed on plots of Colorado blue spruce mixed with birch, while in pure stands of Colorado blue spruce led to a reduction in aboveground biomass.
For the Colorado blue spruce mixed with birch plot compared with only Colorado blue spruce plot were documented favourable soil properties, increased supply of total nitrogen, phosphorus and potassium. Rowan tree on an intact soil surface exhibits the lowest reaction pH as humus and in the mineral, high hydrolytic acidity, extremely sorption unsaturated soil state, high content of ion Al3+ and low content of available calcium, although was applied liming. Technical and biological reclamation (Boleboř III.) has a long-term positive effect on the average height and breast-height diameter of Colorado blue spruce and white pine. The growth dynamics of European larch and Lodgepole pine were affect only at the beginning. Meliorated stand of Gray Alder has very good growth dynamics, comparable with Larch and Lodgepole pine. The big problem is the game impact, especially in Lodgepole pine, which led to the destruction of all individuals. Colorado Blue spruce in terms of biological reclamation is totally inappropriate. This Spruce has reduced resistance to abiotic factors, which often suffer uprooting and breakage. During the 21 years the Clorado Blue spruce mixed with birch accumulated of 66,09 t.ha-1 humus matter with better properties also in the deeper horizon. Colorado Blue spruce accumulated 54,11 t.ha-1 of humus matter. Rowan tree accumulated on the intact soil largest amount of humus matter (194,98 t.ha-1), however acidifies the deeper horizons. The stand of Norway Spruce occurred during the reporting period a decrease of 47% to 107,03 t.ha-1. The decline may be associated with more open stand and due to air liming.
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Modelling Scenarios of Development of Small Agriculture Businesses
Koláčková, Gabriela ; Tichá, Ivana (advisor) ; Stanislava, Stanislava (referee)
The paper deals with the dynamic simulation of possible development scenarios of small farmers. The model is based on the official data sources but also on the qualitative research of small farmers. The modelling structure reflects the specifics of the examined field and personal and social specifics of small farmers. For the purposes of the analysis, the business model describes the value creation in the small farms, thereafter the model is extended into dynamic simulation model and the selected scenarios of development are simulated.
The analysis shows the impact of the current setup in the field. Despite the paper contains the optimistic scenarios, simple change of parameters leads to unsustainable situation. The pessimistic scenarios grow from realistic conditions when parameters reflects the recent period settings. This clearly depicts the influence of weak market position of the farmers and advocates the diversification tendencies.
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