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Climate change caused by volcanic eruptions
Kolářová, Iveta ; Vokoun, Martin (advisor) ; Soukupová, Jana (referee)
This Bachelor thesis is engaged in climate changes caused by volcanic eruptions and explains, why after major volcanic eruptions follow volcanic winters. The first chapter shows the formation of volcanic activity and relations to climate changes. In three parts of the second chapter are described sectional factors (solar activity, problems of ocean currents and at-mospheric flow) to climate changes. In the third chapter are mentioned issues of science discipline of paleoclimatology and historical climatology, which combines a lot of disciplines as a geology, botany, zoology and more. The fourth chapter presents the main part of the work, because in this part is a description of the selected major volcanic eruptions of the last millennium and their consequences in the period after an explosion from the viewpoint of abnormalities in the weather. In conclusion of the Bachelor thesis is a search for an answers to question: Risks of powerful eruptions in the future and their impact on the human population.
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Route truck transport planning for company Blažek a synové s.r.o.
Němcová, Michaela ; Fejfar, Jiří (advisor) ; Kvasnička, Roman (referee)
This bachelor thesis deals with the planning of routes for truck transport company Blažek a synové. The aim is through appropriate economic and mathematical methods to find a suitable route, while that would be a minimal cost.
The literature review describes the basic terms on this topic. Primarily i tis focused on logistics and road car transport. There are also so described the methods by which it is possible to solve this problem.
Practical work is divided into two parts. First, it is assumed that the circuit will take a larger car that can carry all at once. Therefore, in this case, Vogel's approximation method is used and the best route for the company is chosen. In the second part, on the contrary, it is assumed that smaller cars must be taken so the route is divided into circuits. In this case Mayer's method is used, which divides the route into three areas. Again, the best route is selected.
In the end of this work there is evaluation. Assessing the financial terms and there is also a comparison of actual mileage of the routes used and calculated routes chosen methods. The comparison shows that the larger cars company save more money and also driving less kilometers.
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Effect of Exchange Rate Hedging on the Performance of Collective Investment Fund
Pfeiferová, Daniela ; Valder, Antonín (advisor) ; Jiří, Jiří (referee)
Collective investment is among the fastest growing areas of investment in financial markets. Its importance within each economy is influenced by the level of development of the capital market. The beginnings of collective investment in the Czech Republic are associated with the coupon privatization in the 90s of the last century. The basic advantages of this method of investing can include risk diversification, professional portfolio management, liquidity of the investment, regulation and tax benefits. The theoretical part describes the historical development of this business in the financial market. The systematization of collective investment was proposed according to the subject of investing, the method of returns distribution to investors, the terms of investment strategy, the investor's investment profile and according to the existing legislation. Transparent classification schemes were created for particular perspectives. The analytical part of the thesis analyzes the processes used to measure the performance of mutual funds, characterization of the risks associated with collective investment and the possible ways to hedge the foreign currency exchange rate risk. The outputs of the thesis respond to two hypotheses: H1: The monthly cost to hedge the foreign exchange risk affects the monthly performance of the mutual fund on the basis of the correlation in time series. H2: Is the information on the costs of exchange rate hedging required for quality decisionmaking for a small investor (consumer).
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Optimizing controller settings in terms of quality of work gasoline engines E85
Kotek, Tomáš ; Pexa, Martin (advisor) ; Malaťák, Jan (referee)
The work deals with optimizing the operation of spark ignition internal combustion engine on fuel E85. The theoretical part is devoted to the issue of biofuels in terms of production, distribution and use in internal combustion engines.
The experimental part is devoted to the design and verification of the additional control unit (ADU) which solves the optimisation of operation unmodified engine on E85.
The first part of the experiment is dedicated to the design and construction of ADU with aim to faultless operation of the engine on E85.
The second part of the experiment was devoted to optimisation of engine operation in terms of fuel consumption using dynamic changes of the injectors opening time. Part of the experiments was an evaluation of emissions production and impact on the performance parameters of the engine.
The final part of the experiment evaluates the achieved results at the various settings strategy of ADU and compares them with results during engine operation on prescribed fuel N95.
By the dynamic change of the injector opening time were reached decrease in fuel consumption by about 5%, reduction in CO production by around 70%, approximately fourfold increase in the production of NOx emissions and about 50% decrease in production of particulate matters.
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Surface runoff generation and its erosion processes
Kalibová, Jana ; Kovář, Pavel (advisor) ; Štibinger, Jakub (referee)
Research of model simulations of hydrological data for water resources studies and field and laboratory experiments testing the effectiveness of erosion control geotextiles using rainfall simulators is summarized in this dissertation. The results of the research have been used to suggest a water regime optimisation in the catchment of a former mining pit Medard-Libík. Although agricultural and forestry reclamation measures have been applied, rill erosion still appears on some slopes within the catchment. The soil loss and sediment transport result in the deterioration of the crop yield, cause damage on the road and drainage systems and also influence the quality of water in the lake arising by flooding the former mining pit.
The first part of the dissertation provides a review on surface runoff and its erosion processes. Next, bio-technical erosion control measures on slopes are summarised. The third part of the dissertation is devoted to a simulation of surface runoff on a model slope in the Medard Catchment. The main aim was to test whether the KINFIL model is suitable for the simulation of the effectiveness of erosion control geotextiles and suggest an appropriate erosion control measures for the eroded slopes in the Medard Catchment.
The KINFIL model seems to be a useful tool to quantify the effectiveness of individual erosion control products and measures in order to find the most convenient option. The simulations carried out in the dissertation corresponded to the results of field and laboratory experiments testing the impact of geotextiles on surface runoff and soil erosion published earlier.
A well-balanced rainfall-runoff regime in the Medard Catchment would increase the stability of the landscape, reduce the cost of restoration of the damage caused by erosion to road and drainage systems and improve the water quality by elimination of the sediment transport. The results of this dissertation may be offered to the public administration or private stakeholders to control erosion within the reclamation of areas affected by mining activities.
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Bionomics and physiology of stored product mite Tyrophagus putrescentiae (Acari: Acaridida)
Rybanská, Dagmar ; Ryšánek, Pavel (advisor) ; Vladimír, Vladimír (referee)
The infestation of foodstuffs by mites is connected to health risks and economic losses. Tyrophagus putrescentiae (Schrank, 1781) is a cosmopolitan generalist feeder that prefers foodstuffs of high-fat and high-protein content. The stored product mite T. putrescentiae is an emerging and predominant pest of dry dog food. It is an emerging source of allergens in stored products and homes. The results of this study have important implications for predictive models of stored-product mite populations in dry dog food. High-fat and -protein food accelerated T. putrescentiae population growth compared with the high-carbohydrate diet.
The results increase the medical importance of the mite allergens detected in the feces. The cocktail of allergens, i.e. feces covering chitin, mite allergens and bacterial toxins, represent high risks for the mammalian immune system. The association of the mite with Bacillus cereus is to the medical importance.
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Evaluation of cow fertility on profitability of milk production
Čítková, Dana ; Stádník, Luděk (advisor) ; Dalibor, Dalibor (referee)
Objectives of this study were to evaluate effects of milk production level and calving interval, resp. days open period length on the lactation curve parameters and milk production profitability. Data were obtained from Holstein dairy farm. From our results can be stated, that cows with the longest days open period length reached significantly the highest lactation persistence. Due to their ability to maintain high milk productivity after peak day, average daily milk yield was not in these cows, despite long lactation, lower than in cows with shorter lactations. From the economic point of view, milk production profitability with calving interval length decreased and with milk production level increased. Low profitability in cows with long days open period caused high replacement and fertility costs. Feeding costs despite expectations didn´t differ between these groups. All early lactating cows are fed with the same expensive concentrated feeding ration, thats why there is not possible to save feeding costs in high persistent cows with low milk production increase after calving
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Environmental risk assessment of ornamental aquaculture
Patoka, Jiří ; Kalous, Lukáš (advisor) ; Antonín, Antonín (referee)
The ornamental aquaculture comprises both outdoor and indoor keeping of aquatic animals and plants for ornamental purpose which is a very popular hobby with many followers worldwide. It is also commercially profitable for specialized producers and vendors. Associated environmental risks include particularly introduction of non-native species, biological invasions and intensive field capture of exploited and marketed species. Since subsequent regulation, mitigation and eradication of naturalised alien species is very difficult and ineffective in many cases, the most important above all is to prevent new introductions. This trend is accented with a short delay in European legislature. The European Union (EU) currently initiates formation of list of the most invasive alien species. Although invasive potential of certain ornamental species such as red-eared slider (Trachemys scripta elegans) is well known, the vast majority of traded species has never been tested and analysed from this point of view. Publications attached to this thesis are focused on monitoring and survey of market with ornamental animals, such as fishes and crayfishes, with special emphasis on list of advertised species, size classes, prices, origin and availability on market. With use of predictive models the probability of naturalisation and potential invasiveness of mentioned ornamental species were estimated. These information are supported by analysis of hobbyist behaviour. Results in present thesis highlight known environmental risks associated with ornamental aquaculture and also show detailed information about overlooked risks from the Czech Republic's as well as from EU perspective. Therefore this thesis should to help formation of aforementioned list of the undesirable species.
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Influence of Customers Involvement on Brand Loyalty
Vebrová, Tereza ; Hron, Jan (advisor) ; Rojík, Stanislav (referee)
The dissertation thesis focuses on identifying relationship between brand loyalty and customer
product involvement. The main goal is to find out whether customer product involvement has
a positive effect on brand loyalty. In the theoretical basis are defined the main terms of brand
loyalty and customer product involvement and are discussed various approaches of authors who
examined the issue. The own research follows after the theoretical part whose primary data was
collected by using an electronic questionnaire. The research was applied to the area of
telecommunication services in the Czech Republic. On the basis of factor analyses were
evaluated factors a web-based brand loyalty and customer product involvement with these
factors were then made cluster analyses to find customers segments. Using correlation analyses
were determined the effects of sociodemographic variables on brand loyalty and customer
product involvement. At the same time it was also found the relationship between brand loyalty
and customer product involvement. The research results are used for the development of the
discipline, are discussed in the context of previous studies and are described in terms of
theoretical and practical use.
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Application of mathematical models for simulation of hydrological conditions in selected streams
Kurková, Marie ; Vašků, Zdeněk (advisor) ; Michal, Michal (referee)
Flood is a natural phenomenon that occurs at different intensities and irregular time intervals. As to natural disasters, floods represent the greatest direct threat for the Czech Republic. They may cause serious critical situations during which not only extensive material damages are done, but may bring also losses of the lives of inhabitants in affected areas as well as vast devastation of cultural landscape including environmental damages. Important from the viewpoint of the elimination of potential threats and consequences of such events is the information issued by flood forecasting service about the character and size of flood areas for individual N-year flood discharges and specific flood scenarios. An adequate image of depths and flow rates in the longitudinal or cross profile of the watercourse during a flood event is provided by the hydrodynamic model. This is why the information obtained from the hydrodynamic models occupies a privileged position from the viewpoint of the protection of citizens' lives and mitigation of damage to their property. The first study is situated on the river Úhlava in meadows by Příchovice near the town Přeštice. The proposal of flood-protection measures is contained in Territorial control documentation. The documentation was elaborated on the basis of hydraulic calculations and experiences from the flood in August 2002. The mathematical model is practically used in the study of analysis of proposed flood-protection measures. The analysis is based on mathematical simulation of water outflow and water level on the river Úhlava. It is possible to use the non-commercial software Hec-Ras, version 3.1.1., for the simulation itself. One of the points of view of the possibility of using proposed flood-protection measures is total efficiency. The mathematical model is posssible to use as a basis of support for realization of proposed flood-protection measures on the river Úhlava in meadows by Příchovice within the grant programme "Program prevence před povodněmi II" under the control of the Ministry of Agriculture. In the second case the mathematical model is practically used in the study of hydrotechnical analysis of streams in cadastral unit. The analysis is based on matjematical simulation of water outflow and water level on chosen streams. It is possible to use the noncomercial software HEC-RAS for the own simulation. The analysis should be shown on dangerous places in the interest place. The mathematical model is possible of using to use as basis for revaluation of action in spatial plan or for view of the flood-protection measures in the village Mochtín. Basic input into the hydrodynamic models is represented by altimetry data. One of ways to obtain such data is through the method of aerial laser scanning (ALS) from the digital relief model (DRM). This method is considered one of the most accurate methods for obtaining altimetry data. Its bottleneck is however incapacity of recording terrain geometry under water surface due to the fact that laser beam is absorbed by water mass. The absence of geometric data on watercourse discharge area may perceptibly affect results of modelling, especially if a missing part of the channel represents a significant discharge area with its capacity. One of methods for eliminating the deficiency is a sufficient channel recess by means of software tools such as CroSolver. The third submitted paper deals with the construction of a hydrodynamic model using 5th generation DRM data, and compares outputs from this model at various discharges with a model based on the altimetry data modified by using the CroSolver tool. Outputs from the two hydrodynamic models are compared in HEC-RAS programme with the use of recessed data and with the use of unmodified DRM. The comparison is done on the sections of two watercourses with different terrain morphology and watercourse size. A complementary output is the comparison of inundation areas issuing from both model variants. Our results indicate that differences in the outputs are significant namely in the lower discharges (Q1, Q5) whereas for Q50 and Q100 the difference is negligible with a great role being played by morphology of the modelled area and by the watercourse size.
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