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Current Induced Magnetization Dynamics in Nanostructures
Uhlíř, Vojtěch ; Thiaville, André (referee) ; Ravelosona, Dafiné (referee) ; Šikola, Tomáš (advisor)
Předkládaná dizertační práce pojednává o problematice pohybu doménových stěn (DS) vyvolaného spinově polarizovaným proudem v magnetických nanodrátech na bázi spinového ventilu NiFe/Cu/Co. Jedná se o tzv. efekt přenosu spinového momentu. Multivrstevnatý systém NiFe/Cu/Co, kde se doménová stěna pohybuje ve vrstvě NiFe, vykazuje velmi vysokou účinnost přenosu spinového momentu, což bylo v literatuře potvrzeno na základě magnetotransportních měření. Tato práce má za cíl pozorovat stav DS během jejich pohybu, pomocí fotoelektronové mikroskopie kombinované s kruhovým magnetickým dichroismem. Tato technika využívá synchrotronové záření, které svým časovým rozlišením umožňuje sledovat dynamickou odezvu magnetizace na elektrický proud. Podstatnou částí řešení byla optimizace růstu vrstev NiFe/Cu/Co kvůli snížení magnetické dipolární interakce mezi vrstvami. V práci je také řešen způsob přípravy nanodrátů litografickými metodami. Byly provedeny dva módy měření: i) kvazistatický, tj. pozorování DS před a po injekci proudu do nanodrátu a ii) dynamické měření, kde je DS sledována během působení proudového pulzu. S využitím kvazistatickém módu byla vypracována rozsáhlá statistika pohybu DS: i) byly naměřeny jejich vysoké rychlosti přesahující 600 m/s za působení průměrné proudové hustoty nutné k posuvu doménové stěny - 5x10^11 A/m^2; ii) DS jsou v systému NiFe/Cu/Co velmi silně zachycovány dipolární interakcí mezi NiFe a Co způsobenou nehomogenitou krystalové struktury ve vrstvě Co. V dynamickém módu bylo odhaleno, že působením Oerstedovského pole kolmého na nanodráty v rovině vzorku se magnetizace ve vrstvě NiFe silně natáčí. Tento efekt přispívá k vysokým rychlostem DS pozorovaných v nanodrátech NiFe/Cu/Co.
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Study of Post-Discharge Processes
Soural, Ivo ; Hrachová, Věra (referee) ; Brablec, Antonín (referee) ; Krčma, František (advisor)
The decaying plasma was studied by the optical emission spectroscopy. DC discharge created at 45 – 200 mA in Pyrex and Quartz tubes in flowing regime was used. The emission of three nitrogen spectral systems (1st and 2nd positive and 1st negative) were studied in time evolution for pressures of 500 – 5 000 Pa at two wall temperatures – ambient and liquid nitrogen (150 K inside the decaying plasma). Results showed that all three nitrogen systems (respectively N2(B, v), N2(C, v) and N2+(B, v) states as their origins) had their population maxima called pink-afterglow in the afterglow part. These maxima decreased with the increase of pressure for all systems, and moved to the later decay time. Maxima increased with discharge current (respectively power) and moved to shorter time. Populations at temperature of 150 K were measured due to the experimental arrangement from 17 ms, only, and thus pink aftergow maximum wasn’t observed (only at 5 000 Pa some maximum was recognized). Populations were smaller at 150 K that populations measured at laboratory temperature at the middle decay time (50-100 ms). At the late time, the populations were higher at lower temperature at lower pressure. Higher shifts (in intensity and decaytime) of pink afterglow maxima were observed in Quartz tube in comparison with their values in Pyrex tube. Besides the populations, rotational temperatures of selected bands of three observed spetral systems (for 1st negative 0-0 band, 1st positive 2-0 band and for 2nd positive 0-2 band) were measured. Rotational temperatures were monitored from presumption that this kind of temperature is equal to temperature of neutral gas (at local thermodynamic equilibrium). Results from 1st negative and 1st positive system showed strong decreasing of rotational temperatures up to about 10 ms at post-discharge begin, then temperatures were constant up to 20 ms of decay time and after that they grew up. Temperatures increased with the increase of current. The part with decreased temperature correlated with pink-afterglow part of post-discharge. Unfortunately, rotational temperatures of 2nd positive system had bad reproducibility and the time profile shape was opposite. Experimental results were compared with numerical kinetic model created by group of prof. Vasco Guerra at Instituto Supetior Técnico in Portugal. Several sets of conditions for simulation at 500 and 1 000 K in active discharge were applicable for the calculation corresponding to the experiment. Comparison of numerical simulation and experimental data done for N2(B) state demonstrated that maxima populations in pink afterglow are depended on the temperature difference between active discharge and post discharge. Maxima populations were supposed in pink afterglow disappeared if the same temperatures in active and post discharges were supposed. Temperature in active discharge is higher at higher apllied power, as it was showed from rotational temperatures observation. The results clearly showed that real temperature profile must be included into the kinetic model.
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Valuation of total damage to a house caused by fire
Hornychová, Michaela ; Nykodýmová, Veronika (referee) ; Šmahel, Milan (advisor)
The aim of the Thesis is to determine the amount of indemnity for the total damage caused of the wooden detached house caused by fire, find out the costs of bringing the property to its original state and evaluate the price of the original and after an insured event the newly established building. The theoretical part is devoted to the basic concepts and methods in the field of real estate valuation and insurance and the liquidation of insurance events. On the introduction and theoretical part is followed by a practical part in which I apply the theoretical information on the real, by fire stricken the wooden family house, I approach the location and describe the building technical condition before and after the occurrence of the insured event. I find a new price of the real estate at the time of approval, the current price before and after the occurrence of the insured event and the new price of an identical family house without the structures which have been preserved and have not been damaged by the fire or fire-fighters. At the conclusion of the Thesis is the insured value of the building after repair of damage compared with the insured value just before the occurrence of the insured event.
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Business Environment in Russia - Stability, Potential Advantages for Czech Republic and the Impacts of Ukraine Crisis
Pardíková, Barbora ; Petříček, Václav (advisor) ; Bolotov, Ilya (referee)
This study focus on evolution of the business environment in Russia since the fall of Soviet Union, its main features and the impacts of Ukraine Crisis on it. At first, the term business environment is generally described. Next part is dedicated to the most important steps of transformation process Russia underwent and the consequences of 1998 Russian financial crisis. Evaluation of the current performace is based on main economic indicators and the rankings created by international organizations. Second part describes the roots and the development of Ukraine Crisis and the timeline of the measures imposed. Impacts are examined not only from macroeconomic view, but also from the point of view of czech companies exporting to Russia.
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Area analysis in term of possible emergencies occurrance
VACKOVÁ, Denisa
Hand in hand with the evolution of mankind and the improvement of scientific and technical progress of the society new risks and threats occurred, regardless of more suitable living conditions. At the beginning there were only dangers caused by nature, but in the course of time new threats of anthropogenic origin emerged. Even in the Czech Republic emergency risks or critical situations may appear. Besides serious road accidents and natural disasters like floods, fires, hurricanes, erosions, and snow avalanches there is a big probability of disasters caused by leak of chemical substances. Therefore a timely prevention is important in order to avoid such events. In the Czech Republic a system of crisis management was set up to deal with prevention and solution of emergencies and critical situations. In my work I focused on the methods used for analysis of the area of South Bohemia, because they provide us with a survey of risks and threats in a particular area and may result in decreasing of these risks. This work will be used to work out an alarm plan of an integrated safety system of South Bohemian region. It will form one of the supplements of the study that is now being processed and that concerns the area placement of fire brigades in South Bohemian region.
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Půdy dinarské oblasti - management a ochrana
Bešťák, Ondřej
The aim of this bachelor's thesis was issue and management of Dinaric area. It focused on geomorhological, geological and pedological aspects this area. It consists of area's geomorphology, climate and land using. In the next part there is a article about geological and geomorphological evolution of Croatia and erosion like very important aspect and impact on it like fire and wind.. The last part describe of legislative of Croatia and their effect on landscape protection.
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A comparison of legal regulation of forest protection in the Czech Republic and Sweden
Norman, Michaela ; Žákovská, Karolina (advisor) ; Damohorský, Milan (referee)
Forests extend on about 4 billion hectares on the planet Earth, which makes up approximately one third of the total land area and is probably one of the most important environmental elements on the planet.In the Czech Republic forests cover about 33.7% of its land area.Out of Sweden's total land area, which is 41.3 million hectares, there is 23 million hectares of forest land. That is more than half of its total area. Creation of clear-cut areas, loss of the forests natural evolution information, waste majority of artificial forest, storm or fires are just some of the indicators of unsatisfactory conditions of forests. Therefore there is a strong importance for forest protection by means of legal regulation - International, European and especially national law, to be capable of leaving this heritage in a good condition for future generations. In this work I will focus on the comparison of forestry law in the Czech Republic and Sweden - from formal and also material point of view.
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Particularities of diplomatic and business protocol of Spain
Krejčová, Petra ; Gullová, Soňa (advisor) ; Laschoberová, Libuše (referee)
Spain - land of sun and fire, country of dance and singing, country of passion and joy of life, land of horses and bullfighting, land of wine and celebration or country of epic heroes and battles. So, or otherwise, imagine many foreigners this State located on the Iberian Peninsula and representing also the gateway to Latin America. Kingdom of Spain and its culture and traditions have undergone a long evolution and many changes over the centuries and shows the effects of influence not only of European but also Arabian and Indian cultures. These factors significantly affect the Spanish way of trading, the treatment of partners, negotiation or diplomatic and business relations. Although Spain is a part of Europe and since 1986 also a member of the European Union, it still has its specific differences from other European states, which must be taken into account when establishing and maintaining any relationship, whether of business, diplomatic or cultural nature. The goal of my work is, with the help of Spanish literature authors, to characterize the business and diplomatic protocol of Spain and to highlight the most significant differences related to cultural and historical facts. Areas of interest are, for example, the style and methods of negotiation, business etiquette, business and social events, the specificities of royal protocol and other factors of social life, which blend with the world of business and diplomacy. The differences are more pronounced in the area of business, as diplomatic protocol and its rules are governed by international treaties, particularly the Vienna Convention on Diplomatic Relations from 1961 and the Vienna Convention on Consular Relations from 1963, and the differences between countries are less apparent or none. In Spain, this issue is given much attention and many professional publications have come out on similar issues. Professional and informal social etiquette have their strong and respected position here, and with the increasing importance and formality of contacts, their importance is increasing as well. A model and image of the perfect knight of past times has outlasted in a modified form to this day. The role of family and differences in status and roles of men and women can not be ignored. In our country, there are these issues an object of much less interest and often then occurs the failure of negotiations or the failure of business contacts only because of ignorance and misunderstanding. My aim is therefore also to provide a better view of the Spanish country and culture from the perspective of a potential trading partner and enable an easier understanding of the Spanish way of life, thinking and the resulting negotiations. The potential of the country for our manufacturers and retailers is big and successful penetration of the Spanish market may also be the first step into the business waters of Latin America.
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Multicultural Education per ring ceramics advanced
Malinová, Eva ; Skarlantová, Jana (advisor) ; Havlásek Tatarová, Lucie (referee)
I have called the work Multicultural Education pet ring ceramics (advanced). The goal is to introduce children of Interest Advanced ceramic ring formation and evolution of the world's continents, through awareness and understanding of culture and life of different nations, with the influence of the environment, society and the welfare of ceramic production in different regions on Earth. Final output will consist of two days of firing zakuřované ceramics exhibition of the Academy of the House of children and young people, participation of children in ceramic products for the contest organized by the DDM and SVC Regional Office.
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