|
|
Sensitivity analysis of flow through the vanes of the VNT mechanism
Čech, Martin ; Mrázek, Radim (referee) ; Vančura, Jan (advisor)
This diploma thesis analyzes the effects of various parameters of vane profile and position of VNT mechanism on the size of aerodynamic force which acts on the vanes and on the position of neutral axis of the vane. A CDF simulation was created to do this analysis, and the results of the simulation were evaluated. Thesis also deals with turbochargers in general and with other methods of their regulation.
|
|
|
Ice Hockey Stadium
Čech, Martin ; Barnat, Jan (referee) ; Pilgr, Milan (advisor)
Work deals with variant design of steel structure of ice hockey stadium located in Opava. It is a three-aisled hall with shape consists of intersection of ellipse and rectangle with dimensions 70 x 82m. The roof has cylindrical shape with approx. 50 m radius. The building is about 14 m high. Object is divided to three parts – main aisle and two side aisles. The main aisle contains of a rectangle of dimensions 40 x 42 m and two semicircles of radius approx. 20 m. Frames of main aisle are made of arc roof truss connected to steel plate columns. The side aisles with rectangular shape with dimensions 15 x 42 m are connected to main aisle. The structure of side aisle is made of a sloped roof truss. Longitudinal bracing and cross bracing are used to obtain spatial rigidity of the structure. Roof and wall cladding is made of Kingspan sandwich panels.
|
|
|
Technical-economic models of waste-to-energy plants
Čech, Martin ; Touš, Michal (referee) ; Pavlas, Martin (advisor)
Main principle of the thesis is to create technical-economic model of municipal waste-to-energy plant. This model is suitable for different technical parameters of various incinerators and there is not necessary to create new model for each new incinerator. The model also includes basic economic aspects of technology and service of the municipal waste incinerator. The importance of municipal waste incinerator construction, their current situation and planned future in Czech Republic are also mentioned in the thesis.
|
|
|
Business Plan
Čech, Jan ; Čech, Martin (referee) ; Bayerová, Vladimíra (advisor)
This work puts mind to process of business plan in section of delivering services. I hold forth on analysis of a market and analysis current status of company in this work and then I devote to project on upgrading the company.
|
|
|
Server clustering techniques
Čech, Martin ; Polívka, Michal (referee) ; Pelka, Tomáš (advisor)
The work is given an analysis of Open Source Software (further referred as OSS), which allows use and create computer clusters. It explored the issue of clustering and construction of clusters. All installations, configuration and cluster management have been done on the operating system GNU / Linux. Presented OSS makes possible to compile a storage cluster, cluster with load distribution, cluster with high availability and computing cluster. Different types of benchmarks was theoretically analyzed, and practically used for measuring cluster’s performance. Results were compared with others, eg. the TOP500 list of the best clusters available online. Practical part of the work deals with comparing performance computing clusters. With several tens of computational nodes has been established cluster, where was installed package OpenMPI, which allows parallelization of calculations. Subsequently, tests were performed with the High Performance Linpack, which by calculation of linear equations provides total performance. Influence of the parallelization to algorithm PEA was also tested. To present practical usability, cluster has been tested by program John the Ripper, which serves to cracking users passwords. The work shall include the quantity of graphs clarifying the function and mainly showing the achieved results.
|
|
| |
|
|
Non-fish prey in the diet of fish-eating mammals, Eurasian otter (Lutra lutra) and mink (Neovison vison)
Tuzarová, Veronika ; Čech, Martin (advisor) ; Poledníková, Kateřina (referee)
The Eurasian otter (Lutra lutra) is considered, along with the American mink (Neovison vison), a significant fish predator not only in the Czech Republic but also in other regions across Europe. One of the goals of this study is to determine, based on available literature, the types of prey that form the diet of the Eurasian otter and the American mink, specifically focusing on the non-fish component of their food and how the percentage representation of these items changes in the diet of both species depending on habitat and season. Another objective is to verify whether the American mink has a higher proportion of non-fish prey in its diet compared to the Eurasian otter. The processed data describing the diet through spraint analysis in biomass units were divided according to climatic regions, i.e., temperate, Mediterranean, and also based on the type of aquatic environment, i.e., stagnant or flowing water. The results of the study indicate that the American mink consumed, on average, three times more non-fish prey (74 % biomass) throughout the year than the Eurasian otter (24 % biomass). The seasonal variation had the most notable impact on the consumption rate of frogs and birds in the non-fish diet of both predators. According to the analyzed data, both predators especially focused on frogs,...
|
|
|
Round goby (Neogobius melanostomus) in the diet of great cormorant (Phalacrocorax carbo): the role of the season and temperature
Starý, Vojtěch ; Čech, Martin (advisor) ; Adámek, Zdeněk (referee)
Round goby (Neogobius melanostomus) is invasive species, present in the Elbe river since 2015. This study The purpose of this study was to find out how piscivorous predators have adapted to its presence, using the example of the great cormorant (Phalacrocorax carbo). The research was carried out on the basis of the analysis of cormorant's pellets, collected at a locality near Velké Březno (50ř40ʹ34.2ʹʹ N, 14ř07ʹ28.5ʹʹ E) under roosting trees in the period from 1 October 2020 to 15 April 2021, during a total of 7 visits. A total of 1,775 pieces of fish, 15 species belonging to 5 families, were determined from the diagnostic bones. Of this number, 1,115 were round gobies, i.e. a total of 62.8 % of the cormorant's food consisted of these fish. However, the weight share of the total reconstructed weight of all fish caught (113.6 kg) was only very small - 6.6 %. The mean daily food intake (DFI ± S.D.) of cormorants was determined to be 423.7 ± 113.6 g. It was found that cormorants hunting only round gobies overwhelmingly do not consume the necessary prey weight to cover their energy expenditure. Furthermore, the dependence of the size of the hunted prey on the average daily temperature was tested. Linear regression did not show any significant dependence in this case. The hypothesis that at lower...
|
|
|
Ellimination of unwanted fish species from dam reservoirs - Possibilities, efficiency and economic evaluation.
Jůza, Tomáš ; Blabolil, Petr ; Čech, Martin ; Draštík, Vladislav ; Holubová, Michaela ; Hůda, J. ; Kočvara, Luboš ; Kolařík, Tomáš ; Muška, Milan ; Peterka, Jiří ; Prchalová, Marie ; Říha, Milan ; Sajdlová, Zuzana ; Tušer, Michal ; Vašek, Mojmír ; Vejřík, Lukáš ; Kubečka, Jan
spontaneous development of populations and the influence of human interventions. For situations where a certain part of the fish population needs to be caught, within the project 'Biomanipulation as a tool for improving the water quality of reservoirs', we tested the available approaches in terms of their effectiveness and difficulty. The target species of catches were mainly cyprinid fish (bream, bleak, roach, rudd, white bream), which feed mainly\non zooplankton and tend to form very large populations. Among the most effective methods of catch during spawning are catches using electrofishing boats and fyke nets. In the non-spawning period, it is possible to carry out mass catches using trawl nets. Catches are effective both before spawning (in April) and during the summer. However, with repeated catches in the same places, their effectiveness decreases as a result of the fish being spooked. The efficiency of the catches partially improves again if the catches are repeated with a break of approximately 1–2 weeks. Catches also vary according to the stocking density of a given water body. With effective catches, the cost of catching 1 kg of fish is in the range of CZK 15–50.
|
|
|
Fourier transform on polytopes and tiling with rectangles
Couf, František ; Kala, Vítězslav (advisor) ; Čech, Martin (referee)
The aim of this thesis is a detailed exposition of the proof of a theorem on nice intervals in d dimensions and a theorem on the properties of harmonic intervals. We introduce first the notions of a nice rectangle and a tiling of a set. Then we extend the notion of a nice rectangle to that of a nice d-dimensional interval. We subsequently prove the main theorem (a closed interval tiled by nice closed intervals is also nice) in d dimensions. Then we define harmonic intervals and prove in detail several important theorems on tiling by harmonic intervals. We illustrate their assumptions with examples which demonstrate their importance. We show the connection between the notions of a harmonic interval and a multiple of an interval for intervals with integral edges at the end of the last chapter. 1
|
guest ::
RSS feed.