38 research outputs found
Monitoring and calibration of machine tools and coordinate measuring machines
Tato bakalářská práce se zabývá rešerší kontroly a kalibrace obráběcích a souřadnicových měřících strojů používaných v mnoha různých odvětvích průmyslu. Hlavními body této práce je představení různých měřicích postupů dle norem, kalibračních postupů a jejich uplatnění.This is a bachelor´s thesis concerning the retrieval of monitoring and calibration of machine tools and coordinate measuring machines, used in many different industries. The main points of the work is introduction to different measurement procedures according to standards, calibration procedures and their application.
MV Network Operation Issues and Elimination of Phase Voltage Unbalance
This article focuses on networks with great phase voltage unbalance. Formerly, it was necessary to operate these networks with an isolated neutral, resistance or solid grounding. The three-phase compensation system eliminates phase voltage unbalance and can substitute or complement the arc-suppression coil. This system enables a more effective operation of distribution networks with non-effectively grounded node, even in networks with a significantly high capacity unbalance
Determination of the Value of the Capacitive Earth-Fault Current in Distribution Networks Operated with Isolated Neutral Point
The new indirect method of measurementand calculation of the phase-earth capacity in networks withisolated neutral point is based on creation of a short-termphase capacity asymmetry in the network. The value of thephase earth capacity in the network can be determinedusing the voltage ratio in the network and the capacity valueof the connected capacitor. When expanded, the method canbe also used for the leakage current estimation.Furthermore, this method can be applied to periodiccontrols of the earth capacitive current value. For theevaluation of the phase earth capacity, a single-purposeautomation can be used and thus the whole process ofmeasurement and evaluation is conducted at a definedperiod (at a given hour, day, month…) or on operator’scommand
Activating function of a didactic game in the foreign language education at primary school
Práce se zabývá využitím aktivizační funkce didaktické hry jako výukové metody v hodinách angličtiny na prvním stupni. Hledá argumenty pro její použití, možné překážky při její plnohodnotné aplikaci a navrhuje překonávání těchto překážek. Výzkumná část objevuje využití didaktické hry v praxi, jak oblíbené jsou různé hry používané ve školách a jejich vazbu na výukový cíl, bez nějž by postrádaly hry své využití v hodině. Zjišťuje, že rozdílné hry mají v různém věku různou oblibu a různé vnímání vazby na výukový cíl.The thesis focuses on using the activating function of a didactic game as a method in the English lessons at primary school. It looks for the arguments supporting using the game at school, the obstacles causing problems using it and suggests possible solutions. The research part seeks different usage of didactic games in real environment, different favour of particular types of games and their relationship to the educational aim. There are found connections between children's age and their positive feelings towards different kinds of games and their ability to reach the educational aim.Katedra primární pedagogikyFaculty of EducationPedagogická fakult
No more blind dates with calcite: fluid-flow vs. fault-slip along the Očkov thrust, Prague Basin
Dating of fracture-filling calcite with U-Pb geochronology is becoming a rapidly adopted technique for determining the absolute timing of brittle deformation in the upper crust. Slickenfibre calcite is a desirable target, as it precipitates between individual fault slip displacement events, and provides additional kinematic information. Here we present a case study of slickenfibres formed on the Očkov thrust in the Lower Palaezoic Prague Basin, Bohemian Massif, utilising a combination of petrographic and in situ methods. We demonstrate that slickenfibre external textures can be preserved, whilst internally primary textures are removed by fluid infiltration and recrystallization, leading to variable U and Pb mobilisation. One slickenfibre yielded a date of ca. 250 Ma, which we interpret as recording fault slip along the Očkov thrust. Another cross-cutting slickenfibre yielded more scattered U-Pb data, with an imprecise apparent age around ca. 95 Ma. This slickenfibre is recrystallised, destroying the primary textures, and exhibits element mobility. The meaning of this younger apparent age is therefore questionable; whereas it likely reflects Cretaceous U and Pb mobility assisted by fluid-flow along the fault plane, it may not reflect a period of fault slip. Our results demonstrate that slickenfibre-based U-Pb dates do not unequivocally relate to fault motion, and that petrographic and elemental analyses are important requirements for interpreting calcite U-Pb data
Pleiotropic effects of niacin: Current possibilities for its clinical use
Niacin was the first hypolipidemic drug to significantly reduce both major cardiovascular events and mortality in patients with cardiovascular disease. Niacin favorably influences all lipoprotein classes, including lipoproteina,and belongs to the most potent hypolipidemic drugs for increasing HDL-C. Moreover, niacin causes favorable changes to the qualitative composition of lipoprotein HDL. In addition to its pronounced hypolipidemic action, niacin exerts many other, non-hypolipidemic effects (e.g., antioxidative, anti-inflammatory, antithrombotic), which favorably influence the development and progression of atherosclerosis. These effects are dependent on activation of the specific receptor HCA2. Recent results published by the two large clinical studies, AIM-HIGH and HPS2-THRIVE, have led to the impugnation of niacin’s role in future clinical practice. However, due to several methodological flaws in the AIM-HIGH and HPS2-THRIVE studies, the pleiotropic effects of niacin now deserve thorough evaluation. This review summarizes the present and possible future use of niacin in clinical practice in light of its newly recognized pleiotropic effects
Structural and anisotropy of magnetic susceptibility records of granitoid sheets emplacement during growth of a continental gneiss dome (Central Sudetes, European Variscan Belt)
František Žák SJ (1862-1934) and the theology of creation
FRANTIŠEK ŽÁK SJ (1862-1934) AND THEOLOGY OF CREATION The thesis is focused on the personality of Czech Jesuit priest František Žák SJ (1862-1934) and his theology of creation. In the first chapter the life story of František Žák is presented - the description of key moments of his life offers a basis for an evaluation of his personality. Consecutively, his writings are summed up in different thematic groups according to author's interest. In the second chapter Žák's main work of systematic theology - Soustavná katolická věrouka pro lid - is portrayed. Themes of different parts of the book are outlined and special focus is put on its fifth chapter, which deals with God the Creator. This question will be examined in the third chapter of this thesis. The fifth chapter of the book will be thematically and formally analyzed - with special regard to the way how Žák uses the evidence from the Scripture and Church Fathers. Finally, author's main work will be examined in comparison with the writings of his contemporaries Josef Pospíšil, Richard Špaček and Jan Valerián Jirsík. Their and Žák's conception of God the Creator is compared. Keywords František Žák Biography Systematic theology Theology of Creatio
Analysis of the Means of Neutral Point Earthing in MV Networks and Their Influence on MV Networks Operation and Protection
Disertační práce je věnována analýze způsobů uzemnění uzlu sítí vysokého napětí (VN) a jejich vlivu na provoz a chránění. Zvláštní pozornost je pak věnována metodám zjišťování hodnoty nabíjecího zemního kapacitního proudu ve VN sítích s izolovaným uzlem, odporově uzemněným uzlem nebo v sítích s kompenzací zemních kapacitních proudů, tj. v sítích s uzlem neúčinně uzemněným přes zhášecí tlumivku. V některých VN sítích se můžeme setkat s vývody, které mají vysoké hodnoty nabíjecího zemního kapacitního proudu. U takovýchto vývodů, kde nabíjecí zemní kapacitní proudy dosahují vysokých hodnot, je nutné přijmout opatření ke zmírnění jejich negativního vlivu. Znalost nabíjecího zemního kapacitního proudu v jednotlivých vývodech VN sítě je důležitá pro správné nastavení zemních ochran. Proto je nutné alespoň orientačně znát nabíjecí zemní kapacitní proudy jednotlivých vývodů. Negativní vliv vysokých hodnot nabíjecího zemního kapacitního proudu spočívá v ovlivnění systému chránění a ve zhoršení ekonomiky přenosu elektrické energie.Katedra elektroenergetiky a ekologieObhájenoThis dissertation thesis deals with an analysis of means of neutral points earthing in middlevoltage networks (MV) and their influence on operation and protection. Special attention is paid to methods of establishment of earth capacitive charging current values in middle-voltage distribution networks with an insulated neutral point, with a neutral point earthed through a resistor, or in distribution networks with an earth capacitive current compensation - i.e. in networks with a neutral point ineffectively earthed through an arc-suppression coil. In some MV distribution networks, we can find feeders which have got high values of earth capacitive charging current. With such feeders, where earth capacitive charging current reaches high values, it is necessary to adopt measures to moderate its negative impact. The establishment of earth capacitive charging current in each feeder of MV distribution network is important for fault protection setting. Therefore it is important to know, at least approximately, the value of earth capacitive charging current in each feeder. The negative effect of high values of earth capacitive charging current involves the impact on protection system and aggravation of electrical power distribution economy
Markovské semigrupy
In the presented work we study the existence of periodic solution to infinite dimensional stochastic equation with periodic coefficients driven by Cylindrical Wiener process. Used theory of infinite dimensional stochastic equations in Hilbert spaces and Markov processes is summarized in the first two chapters. In the third and last chapter we present the result itself. Necessary technical background mostly from operator theory is encapsulated in the Appendix. The proof of existence of periodic solution of corresponding equation is a combination of arguments by Khasminskii, which ensure under suitable conditions the existence of periodic Markov process, and the results of Da Prato, G¸atatrek and Zabczyk for the existence of invariant measure for homogeneous stochastic equation in Hilbert spaces. At the end we derive sufficient condition for the existence of periodic solution in the language of coefficients using the work of Ichikawa and illustrate the results by the example of Stochastic PDE. The work is written in English