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Increasing the life of blanking punch by coating
Šplíchal, Jan ; Lidmila, Zdeněk (referee) ; Podaný, Kamil (advisor)
This Bachelor thesis presents possible methods for increasing the lifespan of cutting tools made of steel 19 436 designed for cutting stator and rotor plates made of silicon steel. These sheets are characterized by high hardness, which adversely affects the edges of the scissors. Experimental hardness measurement on delivered samples has verified the actual heat treatment on the surface and inside the scraper. The measured value 62 HRC corresponds to the input requirements. Based on the literature study, a combination of chemical – heat treatment and coating was chosen as the most appropriate method. In order to preserve the microstructure of the punch produced after the heat treatment, it was necessary to apply the coating by physical vapor deposition, which is characterized by low deposition temperatures. The FeinAl coating will be applied by cathodic arc deposition and is primarily designed to protect tools and cutting tools.
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Comparison of the environmental impact of different car's drive concept
Kopca, Filip ; Blaťák, Ondřej (referee) ; Zháňal, Lubor (advisor)
This thesis describes structure and operation of particular car‘s drive mechanisms, examine and compares their level of harmfulness against living environment. From acquisition, manipulation and distribution of raw material needed for manufacturing vehicles, amount of used propellant, production of emissions during life cycle, resources needed for maintenance, demands of waste disposal and possibilities of recycling.
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Monitoring of Electrode Changes of Negative Electrode for Lead-Acid Batteries by Operando Confocal Microscopy
Hálová, Hana ; Vanýsek, Petr (referee) ; Chladil, Ladislav (advisor)
The thesis is focused on the laser microscopy observation of the negative electrode for lead-acid batteries during their cycling. The surface changes are evaluated during both deep cycling and PSoC (Partial State of Charge) cycling. The mode leads to gradual degradation of the negative electrode – mostly because of irreversible sulfation. The speed of the sulfation can be influnced by additives of the negative active mass added already during production process. The active mass was firstly examined by electron microscope and X-ray diffractometer. The crystal growth during cycling was observed using confocal microscope Olympus Lext OLS4100.
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Selected problems in the process of building operation appraisal for the purposes of expert opinions
Novák, Jindřich ; Pivoda, Bohuslav (referee) ; Puchýř, Bohumil (referee) ; Mikš, Lubomír (advisor)
The basic requirement for a good quality expert opinion are high quality sources of information, i.e. adequately detailed and valid groundwork. This dissertation analyzes groundwork for expert activities in the area of building operation appraisals, handling of information and its transmission within the life cycle of a construction. For this purpose, it is possible to divide the construction according to its functional parts. The thesis puts emphasis on drawing up a budget according to its functional parts, which is clearer for the investors, contractors and real estate administrators as well as the expert. A significant part of the dissertation is dedicated to recommendations on how to determine the usual price of building operations. In this section I define some options of how to determine the usual price of building operations, including their comparison. Likewise, I investigated and compared real agreed prices of building contracts for public commissions. The basic recommendation resulting from this chapter is the recommendation for the Czech statistics department to automate the data collection based on registers of building operations created with one of the budgeting programs (preferably according to functional parts). For the experts, I prepared a set of recommendations based on the analyzed differences between the budgeted prices and those applied in real contracts. There is no generally accepted method to evaluate the losses created due to delays in construction. For the purposes of this dissertation, I investigated the common prices of rent of the individual equipment and then established two approaches to put value on the cost of equipping the site, percentage rate and individual calculation. I examine in more detail the issues related to quantification of costs for wintertime arrangements. At the end of the chapter I define recommendations for experts. With regard to recommendations for establishing discounts from the construction price due to occurrence of defects and unfinished tasks, I analyzed real examples of distribution of defects and unfinished tasks at the moment of delivering the building operation to the investor and discovered that approximately 50% of defects are part of the surface working. Additionally, I analyzed the Czech technical regulations regarding surface working in order to find basis for assessment of the presence or absence of a defect. While investigating the approach to non-removable defects, I discovered incorrectly considered shelf life of waterproofing within the appraisal. Based on this, I investigated the market and determined the shelf life of common waterproofing systems. At the end of this dissertation I carry out a comparison of selected items of the two pricing systems most commonly used in the Czech Republic, URS and RTS. The differences are a result of contemplating using different technologies, varied mechanisms and diverse approaches to determine the costs of material.
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Mortar with alkali-activated matrix
Černá, Hana ; Hela, Rudolf (referee) ; Bodnárová, Lenka (advisor)
The thesis addresses the issue of alkali-activated materials and their manufacturing components. In the theoretical part the description of such materials is provided and the requirements for source materials are defined. The theoretical part further addresses the resistance of alkali-activated materials and their lifespan - namely sulphate resistance, chloride resistance, acid resistance, frost resistance, porosity, carbonation, resistance, abrasion resistance and heat resistance. The experimental part of the thesis focuses on compounding four different mixtures of alkali-activated materials. In the loosened stage, the weight was measured. In the hardened stage the weight was measured as well as the tensile strength when bending, the strength under pressure applied, heat resistance, water and defrosting chemicals resistance and formation of cracks.
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Monitoring of Electrode Changes of Negative Electrode for Lead-Acid Batteries by Operando Confocal Microscopy
Hálová, Hana ; Vanýsek, Petr (referee) ; Chladil, Ladislav (advisor)
The thesis is focused on the laser microscopy observation of the negative electrode for lead-acid batteries during their cycling. The surface changes are evaluated during both deep cycling and PSoC (Partial State of Charge) cycling. The mode leads to gradual degradation of the negative electrode – mostly because of irreversible sulfation. The speed of the sulfation can be influnced by additives of the negative active mass added already during production process. The active mass was firstly examined by electron microscope and X-ray diffractometer. The crystal growth during cycling was observed using confocal microscope Olympus Lext OLS4100.
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The influence of the quality of articulation UHMWPE inserts on the lifetime of joint replacements
Fulín, Petr ; Pokorný, David (advisor) ; Koudela, Karel (referee) ; Gallo, Jiří (referee)
This thesis focuses on the introduction with the problems of high molecular weight polyethylene (UHMWPE) in orthopedics in the first part. It discusses the history, properties and processes that lead to the failure of UHMWPE joint replacement components. The experimental part validates the hypotheses expressed. It acquaints readers with the experimental verification of the effect of different types of sterilization on the oxidative stability of laboratory prepared samples and explanted UHMWPE joint replacement components using methods of infrared microscopy, electron spin resonance, mechanical tests and tests of microhardness. Other experimental measurements on a large set of explanted components of hip and knee total joint replacements validates the hypothesis that the amount of oxidative damage affects the lifespan of joint replacements. The third part of the experimental study maps the degree of oxidative damage in different places of the hip and knee joint replacements. In the final part we experimentally demonstrate the fact that the rate of oxidative damage has an effect on supramolecular structure of the UHMWPE. From the above experiments are concluded clearly defined recommendations for clinical practice, which should lead to extend the lifespan of total joints replacements in orthopaedics....
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The evaluation of overarm throw in elementary school children using two selected methodologies
Filip, Ondřej ; Kaplan, Aleš (advisor) ; Komínková, Linda (referee)
Title: The evaluation of overarm throw in elementary school children using two selected methodologies Work objectives: The diploma thesis aim is to determine and assess the level of overarm throw technique in 1st and 2nd grade of elementary school using two different evaluation methods meda by Haywood and Getchell (2014) and Haibach, Reid and Collier (2011). The results of the evaluation of overarm throw by the methodology of Haywood and Getchell (2014) will then be compared with the results of the evaluation of the diploma theses created by Maryšková (2007) and Králová (2014). The sub-objective is to create an overview of the evaluation of product and process of overarm throw and to determine whether the methodology of evaluating the overarm throw according to Haibachová, Reid and Collier (2011) can be applied to children of elementary school in Czech conditions. Methodology: The study involved 70 probands, of which 35 boys and 35 girls, attending 1st and 2nd grade of elementary school. Monitoring the movement level of the overarm throw was realized by the method of participatory observation. Probands conducted three attempts in the defined area. Two digital video cameras were used for recording for more detailed analysis of motion using selected methodologies. The camera was statically placed to...
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Physiological adaptations associated with body size and longevity in endothermic vertebrates
Pazdera, Lukáš ; Tomášek, Oldřich (advisor) ; Blažek, Radim (referee)
Abstact Lifespan is related to a number of physiological processes that are interconnected. Longevous species are assumed to have evolved certain physiological adaptations that slow down ageing rate and enable long lifespan. The aim of my thesis was to review physiological traits that has been hypothesised to be associated with lifespan, and to evaluate the empirical support for such hypotheses. Studies testing the association of these traits with body size has also been included in my thesis, as body size is known to be tightly related to lifespan. Traits that are reviewed in my thesis due to their hypothesised coevolution with lifespan are as follows: metabolic rate (i.e., a total amount of energy expended by the organism per unit of body mass and unit of time), oxidative stress resistance, telomere length and rate of telomere shortening and intensity of stress and immune responses. Key words: Lifespan, longevity, survival, reproduction, oxidative stress, free radicals, reactive oxygen and nitrogen species, metabnolic rate, immunity, antioxidants
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