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The effect of climate conditions on wheel-rail contact adhesion
Nohel, Rostislav ; Horák, Zdeněk (referee) ; Omasta, Milan (advisor)
Presented master’s thesis is focused on the experimental research of influence of climate conditions on wheel-rail adhesion, where climate conditions are meant two parameters: ambient air temperature and air humidity. These parameters always affect wheel-raid contact and their values change significantly during the year. For presented experimental research was used tribometer Mini Traction Machine (MTM) in configuration „ball on disc“. For determination of influence climate conditions was first found out the influence of air humidity on adhesion at certain temperatures, which varied between (1 to 50) °C. These experiments were performed for two types of discs, where one disc was exposed to leaf extract contamination. After that was assembled influence of both parameters (air humidity and ambient air temperature) on adhesion in the form of a 3D map, where were distinctioned states, when condensation has occured and when didn‘t. Obtained results in this thesis will be used for optimalization of rail vehicle control systems.
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Wireless weather station
Filka, Tomáš ; Novotný, Radovan (referee) ; Levek, Vladimír (advisor)
This diploma thesis deals with a draft of wireless weather station, whose task is to measure basic values inside and outside the home. Measured variables are for example temperature, atmospheric pressure, relative humidity, wind speed and direction or concentration of carbon dioxide (CO2). These data will be transmitted to a web server for later processing. Possible technical solutions are described and the outcome is a designed printed circuit boards, which has been assembled and tested. Resulting system was tested in trial operation.
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Crop water stress assessment using remote sensing approach
ERBEN, Jiří
The present thesis deals with evaluation of crop water stress by means of remote sensing. The first part of the research is focused on the assessment of water stress of sunflowers in a laboratory environment using spectral analysis of the reflected radiation and thermography. Leaf of suflowers temperature were evaluated and using them, the index of water stress CWSI were calculated. Reflection of leaf was evaluated in the wavelengths 350 -2500 nm. From these wavelengths spectral indexes were calculated - NDVI (Normalized difference vegetation index) which detect the presence of living green vegetation, WI (Water Index) which serve to calculate the approximate amount of water in the vegetation and RVI (simple ratio vegetation index) which determine the content of biomass or photosynthetic capacity. After that, they were compared with CWSI. Finally CWSI was compared with the spectral data, and from the resulting correlations they were apparent wavelengths, which correlated with given index more or less. The second part is focused on the assessment of water stress in terms of 4th. level catchment, specifically on catchment "Dehtáře" near Pelhřimov. There were primarily evaluated three biggest areas - fields of winter wheat, field corn and TTP.
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Industrial local exhaust ventilation
Brdečko, Radim ; Štětina, Josef (referee) ; Charvát, Pavel (advisor)
This bachelor‘s thesis deals with local ventilation in industrial working. At the start of work are listed the reasons why is the ventilation very important. In chapter are legislative terms and technical requirements to make humen general comfort during working. Local exhaust ventilation (LEV) is divided into some kinds and types. Filtration in industry is just for overview. The last part deals with appropriate local ventilation to certain technical operation.
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Control and monitoring of climate in groups of terrariums
Pavlišin, Tomáš ; Petyovský, Petr (referee) ; Macho, Tomáš (advisor)
The aim of this master thesis is to propose a system for monitoring and regulating the climate in groups of terrariums using the Raspberry Pi platform and subsequent transparent display through the web server. Each group of terrariums has its own control device that wirelessly communicates with the Raspberry Pi control computer. The measured values are stored in the MySQL database on the control computer. The measured values are graphically displayed on the web page.
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Effect of water temperature on the electrical activity of muscle
Novotná, Petra ; Pánek, David (advisor) ; Jalovcová, Miroslava (referee)
Title: Effect of water temperature on the electrical activity of muscle Objective: Main objective of this work is to determine the spatiotemporal changes in muscle activation depending on different properties of the environment. All this at a defined muscle power output. Measured by hand dynamometer. Methods: This is a case study. Is processed and analyzed the relationship of the forearm muscles against the aquatic environment (different temperatures - 15 řC, 24 řC and 35 řC) and against dry. Muscular power output is defined and measured by hand dynamometer. Muscular power output was determined as isometric contraction flexors of wrist and fingers of dominant hand. It all in three different modes. The research group were included 5 healthy individuals (3 women, 2 men). As objectivization method was determined surface electromyography. Findings: There is no influence of water temperature (15 řC, 24 řC and 35 řC) on spatiotemporal activation of muscle. It all at a defined muscle power output. There is also no changes on spatiotemporal activation of muscle in aquatic and dry. Keywords: muscle contraction, temperature, water environment, surface electromyography, Water Surface EMG
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Viannia development in the vector
Hlaváčová, Jana ; Volf, Petr (advisor) ; Dostálová, Anna (referee)
Leishmania of the subgenus Viannia are protozoan parasites transmitted by phlebotomine sandflies (Diptera: Phlebotominae). They occur in tropical and subtropical areas in South America, where they cause cutaneous and mucocutaneous leishmaniasis. In this thesis, we studied developmental pattern of Viannia group and factors affecting its development within the sand fly gut. First, we investigated Leishmania braziliensis development within the Lutzomyia longipalpis digestive tract. Using GFP-labeled strain we demonstrated peripylar development: promastigotes escaped from the endoperitrophic space, colonized the hindgut and then migrated anteriorly. Four morphological forms were found within the Lu. longipalpis digestive tract: elongated nectomonads, short nectomonads, metacyclic promastigotes and paramastigotes. Furthermore, using the histological methods we demonstrated parasite attachment in pylorus region, while there were only free promastigotes in the midgut; neither form was found attached to the midgut epithelium. The next part was devoted to the effect of temperature on Viannia in Lu. longipalpis. We compared development of two closely related species L. peruviana and L. braziliensis at 20 řC and 26 řC. Leishmania braziliensis developed well in both temperatures tested, L. peruviana developed...
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Heat wave effect on mortality in summer 2003 and 2006 in Prague
Knobová, Veronika ; Hůnová, Iva (advisor) ; Bartoňová, Alena (referee)
Background: During August 2003 and July 2006 there were observed records of high temperature and high concentrations of pollutants across Europe. The effect of heat waves led to significant increases in total mortality, respiratory mortality and cardiovascular mortality. This study evaluates the association between exposure to the heat waves and daily non- accidental mortality, respiratory mortality and cardiovascular mortality in Prague, the Czech Republic. Methods: The effect of heat waves in summer 2003 and 2006 on mortality was investigated using the negative binomial regression (type of the Poisson model). Counts of death were regressed on temperature, long-term trends, season, day of week and concentrations of pollutants (O3 levels, PM10 levels, NO2 levels, SO2 levels, CO levels). We used one day lag. Results: We found an association between the heat waves in summer 2003 and 2006 and daily mortality and mortality on respiratory and cardiovascular diseases. No statistically significant association was detected. The effect of the heat wave was more significant in women. Conclusions: The effect of the heat wave in August 2003 and July 2006 caused adverse effect on the mortality in Prague, though lower as compared to many other cities in Europe. Keywords: heat wave, mortality, temperature, ozone,...
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Variability of cranial size and shape in modern humans
Danda, Hynek ; Velemínská, Jana (advisor) ; Bejdová, Šárka (referee)
Variability of cranial size and shape in modern humans is affected by many different factors. Neutral evolutionary processes: mutation, genetic drift and migration; sex; but also the environment in witch the individual grows andt the food it recieves are responsible for this variability. Due to ethical constrains in experiments on humans and primates is very difficult to determine to what extent is for observed differences responsible selection and what proportion generates developmental plasticity. From the climatic factors temperature most likely forms the biggest selection pressure, which is evident especially on the facial part of the skull. Another important climatic variable influencing skull shape, nasal cavity most, is humidity. Within-population diversity decreases with increasing geographic distance from putative origin of modern human expansion.
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Thermal requirements for plant development
Chuchvalcová, Lucie ; Skálová, Hana (advisor) ; Jarošík, Vojtěch (referee)
Plant development is strongly influenced by temperature. Other factors affect plant development to smaller extent. Plant development is affected by rate of enzymatic reactions which depend on temperature surrounding plant. Temperature and time are integrated into thermal time which is defined as sum of temperatures above temperature at which development ceases which is called base temperature. Cardinal temperature at which is the rate of plant development highest is called optimal temperature. When temperature exceeds optimum temperature rate of plant development, rate of development diminishes in higher rate than it increased between base and optimum temperature. Thermal time is mostly being used in agriculture for rate of development prediction, for optimizing crop yield, for prediction of particular developmental stage of weeds. There are also works that focus on wild plants. The easiest way to study temperature effect on plant development is to study leaf development. Rate of leaf appearance on the main stem and its reciprocal called phyllochron (duration separating appearance of two successive leaves) are plant development characteristics most frequently used. Use of thermal time instead of calendar days improved considerably prediction of plant phenological events. The goal of this bachelor thesis was...
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