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Visual preferences for wind turbines
Běťáková, Vendula ; Sklenička, Petr (advisor) ; Janečková, Kristina (referee)
This dissertation is a selection of three papers focused on visual preference of wind turbines. Visual impact presents the connectivity of the articles, whereas each one deals with the topic from different perspective. First paper "Wind turbines location: How many and how far?" analyses in detail the characteristics of wind turbines themselves, i.e. their number and distance from observer or vantage point in relation to landscape quality. Second paper "How education orientation affects attitudes toward wind energy and wind farms: implications for the planning process" concentrates on respondents´ characteristics, in particular educational orientation, general attitude, occurrence of WTs in respondents´ vicinity and willingness to live close to WTs. Whereas first two papers use same assessment method to analyse differences of WTs perception from different point of view, the third paper "Futuristic Wind Power Systems Suitable as Artistic Sculptures" presents review of WTs appearance in general and proposals of possible future look as an alternative to traditional wind turbines.
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Total contents and speciation of arsenic and selenium in plants growing in soils with different physico-chemical properties
Tremlová, Jana ; Száková, Jiřina (advisor) ; Vymazal, Jan (referee)
This dissertation thesis deals with uptake, accumulation and transformation of arsenic and selenium in plants growing on soils with different chemico-physical soil properties. The contents of arsenic were investigated in 99 wild plant species, coming from 27 different families and 6 different vegetables growing in arsenic contaminated soils. The results suggest that there are species-specific mechanisms which protects certain plants from the excessive uptake of arsenic from the soil. On the other hand, there are plants using a strategy of accumulation, which theoretically may increase the risk of arsenic entry into the food chain, whether through grazing cattle and wildlife or through consumption of vegetables growing on arsenic contaminated soils. The most prevalent arsenic compounds are AsV and AsIII. Other arsenic compounds occure as minor species. An important finding was detection of arsenobetaine in Plantago lanceolata L. and Carex praecox Schreb ..
The contents of selenium were examined in 73 species of wild plants, coming from 29 different families. The results suggest that naturally low levels of selenium in the soil of selected locations along with a low capability of selenium uptake via collected plant species lead to the low content of selenium in plant biomass which may contribute to selenium deficient throughout the food chain. Foliar application of selenate on wild plant communities and on some types of vegetables in our case Brassica oleracea var. italica can have a positive impact on increasing the selenium content in the aboveground biomass of these plants and by extension, increase the selenium content in the human diet. Dominant selenium compounds in the aboveground biomass of the analyzed plants were SeVI and selenomethionine, with variable proportion of other commonly occurring organic selenium compounds, which is mainly affected by plant species.
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Possibilities in monitoring of laser welding process
Horník, Petr ; Mrňa, Libor
With increasing demands on the quality of the welds, it is usual to apply automated machine welding with monitoring of the welding process. The resulting quality of the weld is largely affected by the behavior of keyhole. However, its direct observation during the welding process is practically impossible and it is necessary to use indirect methods. At ISI we develop optical methods of monitoring the process based on analysis of radiation of laser-induced plasma using Fourier and autocorrelation analysis. Observation of keyhole inlet opening is partially possible through a coaxial camera mounted on the welding head and the subsequent image processing. A high-speed rear camera to understand the dynamics of the plasma plume. Through optical spectroscopy of the plume, we can study the excitation of elements in a material. Shielding gas flow can be visualized using schlieren method.
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The impact analysis of the technical devices used by the driver on the reaction time
Kubánek, Ondřej ; Bradáč, Albert (referee) ; Panáček, Vladimír (advisor)
This master‘s thesis analyzes the impact of the use of technical equipment for the driver reaction time. There are described the legal requirements for the use of technical devices by the driver in the vehicle. There are analyzed the types of technical devices used by drivers and mainly discussed the issue of drivers' reaction times. They assessed factors affecting reaction time, ways of measuring the reaction time and the type of reaction times. They discussed earlier research from the beginning of the measurement of reaction times to the latest research, dealing with the measurement of reaction times when using a mobile phone. The practical part is devoted to perform road tests on a sample of drivers and evaluate their reaction times during normal driving and during a call. The measured and evaluated data are commented with respect to the benefits of expert activities in the field of transport.
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Optimization of network flow monitoring
Žádník, Martin ; Lhotka,, Ladislav (referee) ; Matoušek, Radomil (referee) ; Sekanina, Lukáš (advisor)
The thesis deals with optimization of network flow monitoring. Flow-based network traffic processing, that is, processing packets based on some state information associated to the flows which the packets belong to, is a key enabler for a variety of network services and applications. The number of simultaneous flows increases with the growing number of new services and applications. It has become a challenge to keep a state per each flow in a network device processing high speed traffic. A flow table, a structure with flow states, must be stored in a memory hierarchy. The memory closest to the processing is known as a flow cache. Flow cache management plays an important role in terms of its effective utilization, which affects the performance of the whole system. This thesis focuses on an automated design of cache replacement policy optimized to a deployment on particular networks. A genetic algorithm is proposed to automate this process. The genetic algorithm generates and evaluates evolved replacement policies by a simulation on obtained traffic traces. The proposed algorithm is evaluated by designing replacement policies for two variations of the cache management problem. The first variation is an evolution of the replacement policy with an overall low number of state evictions from the flow cache. The second variation represents an evolution of the replacement policy with a low number of evictions belonging to large flows only. Optimized replacement policies for both variations are found while experimenting with various encoding of the replacement policy and genetic operators. The newly evolved replacement policies achieve better results than other tested policies. The evolved replacement policy lowers the overall amount of evictions by ten percent in comparison with the best compared policy. The evolved replacement policy focusing on large flows lowers the amount of their evictions two times. Moreover, no eviction occurs for most of the large flows (over 90%). The evolved replacement policy offers better resilience against flooding the flow cache with large amount of short flows which are typical side effects of scanning or distributed denial of service activities. An extension of the replacement policy is also proposed. The extension complements the replacement policy with an additional information extracted from packet headers. The results show further decrease in the number of evictions when the extension is used.
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Do Consumers Really Follow a Rule of Thumb? Three Thousand Estimates from 130 Studies Say “Probably Not”
Havránek, Tomáš ; Sokolova, Anna
We show that three factors combine to explain the mean excess sensitivity reported in studies estimating consumption Euler equations: the use of macro data, publication bias, and liquidity constraints. When micro data are used, publication bias is corrected for, and the households under examination do not face liquidity constraints, the literature implies no evidence for the excess sensitivity of consumption to income. Hence little remains for pure rule-of-thumb behavior. The results hold when we control for 45 additional variables reflecting the methods employed by researchers and use Bayesian model averaging to account for model uncertainty. The estimates of excess sensitivity are also systematically affected by the order of approximation of the Euler equation, the treatment of non-separability between consumption and leisure, and the choice of proxy for consumption.
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The contributions of the sections (NACE-CZ) to the creation of gross value added
BEDNÁŘOVÁ, Monika
The aim of this thesis was to evaluate the contributions of the sections (NACE-CZ) to the creation of gross value added. The first part of this thesis described the theoretical concepts relating to national economic gross value added. Analytical processes were used for the calculations, which may be used only if we are dealing with an additive link between individual factors. The sections' contributions to the creation of national eco-nomic gross value added were evaluated in the practical part, on the basis of the proc-esses set forth in the methodology. In the given time horizon, contributions by institu-tional sectors and groups of sections classified according to the level of technology showed a certain dependency on the actual economic cycle. Although the strongest in-stitutional sector is non-financial enterprises, they were the ones most affected during the crisis period, together with government institutions. On the contrary, the financial institution sector showed a strong position during the crisis period. In terms of the grouping of the sections according to the level of technology, the greatest contribution to national economic gross value added is by groups B1 and B2. The influence of the economic cycle was noted in all the groups but, according to the results, group C did not react quite as sensitively as the other groups.
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Specificity of insect-plant associations and their role in the formation of plant defenses and speciation
VOLF, Martin
The aim of this dissertation is to investigate what role insect-plant interactions play in the formation of host-plant defenses and in the diversification of both groups. We show that various groups of herbivore respond differently to host-plant defenses. Therefore plant defenses diversify into suites of complementary traits, as individual traits fail to provide protection against specialized herbivores. Further, we identify what levels of host-phylogeny shape the food-web structure of insect herbivores. We show that specialized herbivores are affected mainly by the terminal parts of the host-phylogeny. In contrast, more polyphagous guilds are affected mainly by the mid-levels of the host phylogeny because the effects of terminal or deeper phylogeny seem to be surpassed by other factors in more generalist insect species. In the last chapter, we show how specialized insect-plant interactions generated by tight insect-plant coevolution can influence the speciation in plants over environmental gradients.
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Project management in selected company
POKORNÝ, Radek
This work deals with project management in chosen company. It has two parts. The first part is theoretical, which is focused to theoretical treatment of the subject. It explains what is the project, management of projects, organizations of projects, processes of project management, what is target of project, communication, control, changes and risks and more. In the practical part I focused to concrete company and project management and than I analyzed concrete project. Name of the mentioned company is OHL ŽS, a.s. It is company from Spain, which acts all over the world. In the Czech Republic has the base in Brno. This company has several divisions and every of them is focused to different professional architecture. I have chosen division of structural engineering. This division builds all kinds of buildings. It could be construction of new buildings or reconstruction. To analysis of chosen project I used various business documents, contracts with investor or suppliers, document which include billing, timetable. I especially used my experience with projects of this company, and I was part of this project. Name of this project is Reconstruction of cladding including replacement windows and insulation. During the analysis of project I found a couple major gaps. If we could avoid these gaps, we could increase profit. These graphs is especially in management. At the beginning there were appointed two temporary construction managers. They doesn't care about result project, because they knew that they will not be to the end of the project. These gaps are because there is missing motivation system. Project manager can´t affect results of employees. It doesn´t depend on performance of employees, they always has the same wages. For elimination of these gaps I proposed several suggestions for improvement. The first suggestion is modification and extension of motivation system. New motivation system include personal evaluation. This evaluation depends on performance of employee. The second part is bonus from over profit. The next suggestion is make a new working position. This position would take care about controlling and project documentation. During the building project, especially at the end is construction manager very busy. It depend of decision of construction 63 manager what kind of activity will have prefer. Project documentation and administration or controlling of building works. If they are doing everything correct and technology are respect. Suggested position would take care about invoices, real work, which is done, project documentation, controlling of budget. The third suggestion is purchase of small machinery such as chipping hammers and drills. At this time they rent all devices. Rent is higher than purchase price. The last suggestion is use credit to restoration of fleet. At this time they have obsolete fleet, because the bought all cars by cash. It is not conveniently.
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Vliv klimatických podmínek na chování koz
MOJŽÍŠKOVÁ, Nikola
The aim was to record the basic categories of behavior of milked goats on an organic farm with regard to the different climatic conditions throughout the year. The herd of approximately 100 goats for milk production was kept throughout the year with unlimited access to pasture freely within the enclosure. Followed the basic categories of behavior: feed intake, exercise, lying and standing. There were five investigations done by interval method (interval of 10 minutes) after 24 hours at different macro climatic conditions (rain, mild winter, frost, heat, optimum temperature). In all investigations were the most represented category relaxing form of lying. The goats rested longest at low temperatures approximately (-12C) for 42% of the day. In contrast the shortest duration of resting during high summer temperatures approximately (32C) was 35% of the day. The length of feed intake was relatively stable with the longest intake in winter by up to 10% to 25% of the day. Climatic conditions affect the regime of the day, especially in determining the time of intake. Goats grazed in summer when high temperatures mostly in the early morning, while the optimal temperatures were grazing evenly distributed throughout the day. Goats are very active, which is due to their lively temperament. Increased unrest in the herd was recorded in relentless rain.
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