Small heating units - emissions - fuels - choice

Bakalářská práce se ve své první části zaměřuje na přehled dostupných malých zdrojů tepelné energie. Na toto téma navazuje přehled dostupných paliv a k nim vztažené emise. Třetí částí je tvorba základního algoritmu pro volbu tepelného zdroje. V poslední části práce je navržený algoritmus aplikován na virtuálním modelovém domě Cesmína.The first part of thesis focuses on an overview of small heat energy sources. Second part is an overview of available fuels and their related emissions. The third part is the creation of the basic algorithm to select the heat source. The last part is application of the proposed model to the virtual house Cesmína.

Comments on Skin Effect in Solitary Solid Tubular Conductor

J. C. Maxwell derived formulae for the calculation of current density and current in a cylindrical conductor supplied with variable current. In the 1950s K. Simonyi published a method for calculating current density in a cylindrical conductor made up of two conductors, cylindrical and tubular, of different resistivities. The present paper proves that Simonyi's result is incorrect. The main attention is devoted to the method of calculating current density in a tubular conductor made up of tubular conductors of different resistivities

Stiffness characteristic of front part of the vehicle

So far, in the field of forensic engineering was used to describe the stiffness of the front part of the vehicle only central stiffness characteristic that can be used with sufficient accuracy for frontal crash with a full overlap. However, if the vehicle crashes with only partial overlap so can be central stiffness characteristic limitations in the accuracy of the calculation of the deformation energy. The present article deals with the stiffness of the each parts of the front part of the vehicle for their use in forensic expert practice. Stiffness characteristics was processed for each part of the vehicle, with which you can calculate the exact deformation energy for a specific front part of the vehicle which was damaged in a frontal collision.Doposud byla v oboru soudního inženýrství využívána pro popis tuhosti přední části vozidla pouze centrální tuhostní charakteristika, kterou bylo možné použít s dostatečnou přesností pro čelní nárazy vozidla s plným překrytím. Pokud však vozidlo narazí pouze s částečným překrytím má již centrální tuhostní charakteristika svá omezení v přesnosti výpočtu deformační energie. Předmětný článek pojednává o tuhostech jednotlivých partií přední části vozidla za účelem jejich využití ve znalecké praxi. Pro každou partii předmětného vozidla je zpracována příslušná tuhostí charakteristika, s pomocí které lze vypočíst deformační energii přesně pro konkrétní část vozidla, která je při čelním nárazu poškozena

Analysis of Power Quality Parameters in Off-Grid Systems

Import 03/11/2016Cílem této bakalářské práce je provést analýzu kvality elektrické energie v ostrovní napájecí soustavě, která není připojena k distribuční síti. Dodávka elektrické energie do této sítě pochází z obnovitelných zdrojů elektrické energie, využívající sluneční záření, s možností akumulace přebytků elektrické energie pro následné pokrytí spotřeby v době, kdy nestačí aktuální dopad úhrnu slunečního svitu na fotovoltaické panely. Předmětem této analýzy je najít vztahy nebo souvislosti mezi překročením kvalitativních parametrů elektrické energie a meteorologickými veličinami. Analyzované data pocházejí z měření v roce 2015, které započalo po změně zapojení topologie sítě Off-Grid napájecího systému z AC na DC. Naměřená data z tohoto roku mají odpovědět na klíčovou otázku z pohledu kvality elektrické energie a to, zda-li je nyní možné provozovat ostrovní napájecí systém, využívající fotovoltaické napájecí systémy, autonomně a to bez překročení stanovených velikostí limitů kvalitativních parametrů elektrické energie, zejména podle převzaté evropské normy o charakteristikách napětí elektrické energie, jež je dodávána z veřejné distribuční sítě, s označením ČSN EN 50160.The goal of this thesis is to analyze power quality in Off-Grid system, which isn't connected to distribution network. The supply of electric power to this network comes from renewable resource using solar power source with the ability to accumulate the excess of electric power to use it in times when the actual total sunlight caught on photovoltaic panels isn't enough. The aim of this analysis is to find relations between exceeding qualitative parameters and meteorological quantities. The analyzed data comes from measuring conducted in 2015 which started after the wiring change of network topology of Off-Grid feeding system from AC to DC. The data measured in that year are to answer the key question from the quality of electric energy point of view and whether it is possible to operate autonomic Off-Grid systems which uses photovoltaic supply system, without exceeding the limits of qualitative parameters of electric power, in particular these assumed from European norm labeled ČSN EN 50160 about characteristics of electric power voltage which is supplied from public distribution network.410 - Katedra elektroenergetikyvýborn

Orbispaces and their Mapping Spaces via Groupoids: A Categorical Approach

In this paper, we give an accessible introduction to the theory of orbispaces via groupoids. We define a certain class of topological groupoids, which we call orbigroupoids. Each orbigroupoid represents an orbispace, but just as with orbifolds and Lie groupoids, this representation is not unique: orbispaces are Morita equivalence classes of orbigroupoids. We show how to formalize this equivalence by defining the category of orbispaces as a bicatecory of fractions from the category of orbigroupoids. We focus particularly on laying the groundwork for future work in creating mapping objects for orbispaces which are themselves orbispaces, and providing a concrete description of how this mapping space construction will get its orbispace structure. Throughout this paper, we illustrate our definitions and results with numerous examples which we hope will be useful in seeing how the categorical point of view is used to study these spaces

The identification of chemical compounds that decrease cellular levels of toxic Huntington's disease protein through a novel cell-based assay

Thesis (Ph. D.)--Massachusetts Institute of Technology, Dept. of Biology, 2006.Vita.Includes bibliographical references.Huntington's disease (HD) is a progressive degenerative neurological disorder. Individuals who inherit the IT15 gene with an expansion of the CAG repeat region inevitably succumb to increasingly sever motor, psychological, and cognitive symptoms. I sought to develop an assay system with the capability for identification of chemical compounds that selectively decrease the intracellular levels of disease-causing expanded polyglutamine huntingtin (Htt) protein without reducing the intracellular levels of the potentially protective normal Htt. To achieve this goal I designed a cell-based assay using the enzymatic activity of E. coli [beta]-galactosidase as a reporter for Htt protein levels. I expressed either expanded (97Q) or normal (23Q) Htt fused to the [beta]-galactosidase alpha-subunit ([alpha]) in an inducible fashion in PC12 cells which also expressed the [beta]-galactosidase delta-subunit ([delta]). Complementation between these expressed subunits allowed the formation of functional P-galactosidase. The level of [beta]-galactosidase activity in these [delta]-[alpha]97Q and [delta]-[alpha]23Q cells directly correlated with the amount of a 97Q and a 23Q fusion protein levels, indicating that [beta]-galactosidase activity could be used as a reporter in this system for Htt protein levels.(cont.) I implemented this cell-based assay as a secondary assay to characterize a group of compounds that had been initially identified in a High Throughput Screen because they reduced levels of expanded Htt-fragment fused to GFP. Of the 34 compounds characterized in the -galactosidase [delta]-[alpha]97Q assay, dose response curves and counter-screening with [delta]-[alpha]23Q cells revealed that seven compounds decrease [beta]-galactosidase activity only in [delta]-[alpha]97Q cells. Immunofluorescence demonstrated that two compounds decrease levels of expanded but not normal Htt proteins in the cells. Finally, tests of toxicity on HttQ103 PC12 cell lines, which show specific toxicity following expression of expanded Htt, revealed a significant correlation with the results from the [beta]-galactosidase assay and the identification of at least one compound which continued to meet the criteria for therapeutic intervention in HD. These results support the feasibility of the development of an HD therapeutic strategy based on small molecules which cause a specific reduction of intracellular expanded Htt protein levels and suggest a program of development for such molecules.by Myra Alfert Coufal.Ph.D

Characterising the impact of ergot alkaloids on digestibility and growth performance of lambs

The negative impacts of ergot contamination of grain on the health of humans and animals were first documented during the fifth century AD. Although ergotism is now rare in humans, cleaning contaminated grain concentrates ergot bodies in screenings which are used as livestock feed. Ergot is found worldwide, with even low concentrations of alkaloids in the diet (<100 ppb total), reducing the growth efficiency of livestock. Extended periods of increased moisture and cold during flowering promote the development of ergot in cereal crops. Furthermore, the unpredictability of climate change may have detrimental impacts to important cereal crops, such as wheat, barley, and rye, favoring ergot production. Allowable limits for ergot in livestock feed are confusing as they may be determined by proportions of ergot bodies or by total levels of alkaloids, measurements that may differ widely in their estimation of toxicity. The proportion of individual alkaloids, including ergotamine, ergocristine, ergosine, ergocornine, and ergocryptine is extremely variable within ergot bodies and the relative toxicity of these alkaloids has yet to be determined. This raises concerns that current recommendations on safe levels of ergot in feeds may be unreliable. Furthermore, the total ergot alkaloid content is greatly dependent on the geographic region, harvest year, cereal species, variety and genotype and can vary greatly depending on the chosen analytical method. Considerable animal-to-animal variation in the ability of the liver to detoxify ergot alkaloids also exists and the impacts of factors, such as pelleting of feeds or use of binders to reduce bioavailability of alkaloids require study. Accordingly, unknowns greatly outnumber the knowns for cereal ergot and further study to help better define allowable limits for livestock would be welcome

Modeling And Economic Analysis Of A Crop-Livestock Production System Incorporating Cereal Rye As A Forage

This thesis consists of two chapters using agent-based modeling for a crop-livestock production system incorporating human labor. The first chapter examines the principles used to develop a fundamental simulation pertaining to grazing cereal rye (Secale cereal L.) with calves. Within the software guidelines, the base model has the ability to capture diverse system interactions between livestock/plants and land management with human labor efficiency. AnyLogic incorporates agent-based modeling while combining with discrete event modeling and system dynamics. The purpose of the model was to find the economic returns of grazing cover crops relative to the area of Mead, Nebraska. In our simulation model, we used data from the University of Nebraska-Lincoln Climate Center. The model was developed to create more in depth case studies to help further the understanding of crop and livestock interactions through simulation. AnyLogic is a complex tool that has the capabilities of discovering the interactions between crops, livestock, land, and humans. In the second chapter, we examined the economic returns of grazing cereal rye with calves versus mechanically removing the cover crop. This analysis evaluated production risks due to weather variability and cattle market risk to determine the theoretical best outcome using existing weather and market data. Working with the University of Nebraska-Lincoln’s agronomy and animal science departments, we modified a cereal rye growth production model first proposed by Feyereisen et al. (2006) to match recent on-farm production trial experience in Mead, Nebraska. Based on simulation results over multiple years, it was determined that mechanically harvesting cereal rye is a better option as a long term fixed strategy than grazing cereal rye. This is largely due to cattle market risk during the spring grazing period. The costs associated with mechanically removing the crop depend on farm size and equipment used. Both chapters utilize a model simulating the grazing of cover crops developed using the AnyLogic software while the analysis on mechanically removing the forage was completed with the use of a University of Nebraska-Lincoln cover crop budget. Through bridging the gap between production and economic information, this study sought to develop a financial comparison between the two cover crop strategies for eastern Nebraska farmers. Advisor: Jay Parson