|
STRAIN ENGINEERING OF THE ELECTRONIC STRUCTURE OF 2D MATERIALS
del Corro, Elena ; Peňa-Alvarez, M. ; Morales-García, A. ; Bouša, Milan ; Řáhová, Jaroslava ; Kavan, Ladislav ; Kalbáč, Martin ; Frank, Otakar
The research on graphene has attracted much attention since its first successful preparation in 2004. It possesses many unique properties, such as an extreme stiffness and strength, high electron mobility, ballistic transport even at room temperature, superior thermal conductivity and many others. The affection for graphene was followed swiftly by a keen interest in other two dimensional materials like transition metal dichalcogenides. As has been predicted and in part proven experimentally, the electronic properties of these materials can be modified by various means. The most common ones include covalent or non-covalent chemistry, electrochemical, gate or atomic doping, or quantum confinement. None of these methods has proven universal enough in terms of the devices' characteristics or scalability. However, another approach is known mechanical strain/stress, but experiments in that direction are scarce, in spite of their high promises.\nThe primary challenge consists in the understanding of the mechanical properties of 2D materials and in the ability to quantify the lattice deformation. Several techniques can be then used to apply strain to the specimens and thus to induce changes in their electronic structure. We will review their basic concepts and some of the examples so far documented experimentally and/or theoretically.
|
|
White crow dressed in black. Life's journey of František Jan Kroiher (1871-1948)
CUKR, Jiří
The present rigorous thesis is about the personality of František Jan Kroiher (1871-1948). He represented a very engaged person in a public area. His activity was very extensive and intervened in minor works in the country up to the contacts with the highest clerical and political circles. Individual chapters are devoted Kroiher´s childhood and study, career of the priest in the South Bohemia, his taking part in the reform efforts of the Czech clergy, work in a cooperative and economic sphere, a politic career in Agrarian Party and his extensive journalistic activities and sponsorship. At the end there is evaluation of Kroiher´s personality, followed by the list of sources and bibliography, index of names, a list of abbreviations and supplements. The rigorous thesis was based on prospecting quantity of the archival documents, period newspapers and literature. The present rigorous thesis is about the personality of František Jan Kroiher (1871-1948). He represented a very engaged person in a public area. His activity was very extensive and intervened in minor works in the country up to the contacts with the highest clerical and political circles. Individual chapters are devoted Kroiher´s childhood and study, career of the priest in the South Bohemia, his taking part in the reform efforts of the Czech clergy, work in a cooperative and economic sphere, a politic career in Agrarian Party and his extensive journalistic activities and sponsorship. At the end there is evaluation of Kroiher´s personality, followed by the list of sources and bibliography, index of names, a list of abbreviations and supplements. The rigorous thesis was based on prospecting quantity of the archival documents, period newspapers and literature.
|
|
Zalužanský Brook Restoration Project
Lašek, Jakub ; Kalibová, Jana (advisor)
This thesis contains restoration project of chosen section of Zalužansky brook in Ústecký kraj. Project is processed at the level of documentation for territorial management according to decree no. 499/2006, of buildings documentation. Theoretical part captures professional literature research dedicated to restorations, spatial planning and buildings documentation. Analytic segment closely defines and characterise location of interest at first, although major part consists of designed restoration measures following requirements for creating a building documentation by mentioned decree. Benefit from this thesis is it's possible usage as a background material for documentation created by authorised engineer for water management and landscape planning.
|
|
Documentation of the nature reserve Miletinska bazantnice (Czech Republic)
Stejskalová, Klára ; Skalický, Milan (advisor) ; Martinková, Jaroslava (referee)
The aim of this study is to document the floristic species diversity through research in the natural reserve Miletinska bazantnice. Documentation was carried out on the territory concerned during the growing season of 2015. There was a determination of vascular species. The research was mainly focused on endangered and protected species.
The whole area is part of sites of European importance under the Habitats Directive Natura 2000 Miletinska bazantnice was declared a nature reserve in 1954 with an area of 75, 43 hectares and is part of a small-scale specially protected area. Typical features of the area are remnants of natural Podzvicinsko geobiocenosis and therefore the reason for its protection.
Further it describes the history, characteristics of the territory and the natural conditions that are typical for the locality. These include soil science, climate, hydrological, geomorphological, geological and phytogeographical. On the territory of the nature reserve are recorded two memorial trees. It´s oaks (Quercus robur) called Zizkovy duby.
At present territories were found in protected and endangered species and classified under the Red and black list of vascular plants of the Czech Republic (Grulich, 2012) and Decree of the Ministry of Environment of the Czech Republic no. 395/1992 Coll. Into the category of rare taxa that require additional attention include species such as Carex otrubae, Cerastium lucorum, Daphne mezereum, Galium boreale, Listera ovata and Primula veris. The only species Platanthera bifolia is ranked in the category of endangered under both the Red and black list of vascular plants in the Czech Republic and under Decree.
In the field survey, attention was also paid to invasive species, sorted by Catalogue of alien plants of the Czech Republic (Pyšek et al., 2012) and categorized archeophytes (Arctium tomentosum, Cirsium arvense, Convolvulus arvensis, Chelidonium majus)
and neophytes (Arrhenatherum elatius, Impatiens parviflora) and described their risks (Mlíkovský and Stýblo, 2006)
|
|
Methods of Automated Model Transformations in Information System Analysis
Tůma, Jakub ; Merunka, Vojtěch (advisor) ; Toman, Prokop (referee)
This doctoral dissertation thesis has impact to holistically development extension of information systems. Thesis has impact to analytical models and its transformation methods.
This thesis is focused on models Business Process Modeling Notation (BPMN) and Business Object Relational Modeling (BORM). Model BPMN is developed since 2000. Model BORM is developed since 1993 and it is older. The thesis general target was extension of holistically development of information systems. The main target was to bridge the gap between BPMN and BORM models.
This thesis was inspired by Finite State Machine (FSM). The state of the art describes approaches to models transformation. In the analytical part the mathematical formula are used to describe transformation. This part is used to base for the implementation part. The implementation part contains transformation algorithm its description and verification on the case studies. Impact of developed transformation method is validated on the comparison with the other approaches.
The targets were aimed and documented automated transformation calculus. The impact of automated BPMN and BORM models connection using transformation method. The result is method of automated transformation from BPMN model to BORM model using algorithm. The transformation method is based on the Mealy automaton.
|
|
Cooperation of high schools with external contractors in preparing school educational programs
Tulach, David ; Lačev, Alek (advisor) ; Hochel, Matej (referee)
This thesis, Cooperation of high schools with external contractors in preparing school educational programs, deals with the question whether it would be possible and beneficial for high schools to cooperate with companies on the preparation or modification of their educational programs, with the goal of improving the quality of education. After initial contributions from experts who provided negative replies to this question, the view was focused on the root of the issue - what are the historical pillars of public schools and pedagogy, what does science say about learning and teaching, how pedagogy reacts to the crisis of science. After comparing literal sources and results from interview with the experts, in combination with a trace and activity analysis, a theory was established that public education is reaching a point of crisis, has not changed in its essence since its beginning and that the best solution might be the establishment of alternative educational institutions.
|
|
Employment in a state-funded institution
Brožová, Milena ; Světlíková, Daniela (advisor) ; Pikola, Pavel (referee)
This bachelor thesis is focused on employment in a state-funded institution. It is divided into a theoretical and an empirical part.
The theoretical part deals with analysis of legal regulations and their interpretation. The method of description is used in this part. The focus in legal regulations is on the problems of a state-funded institution, namely on the legal position and functioning and on management. The focus is also on labour relations, from the general definition to the conclusion of employment for a fixed period of time. The analysis of legal regulations is complemented with interpretations of authors of specialized publications.
Direct and indirect quotations are used in the text and are marked with footnotes.
The empirical part of this thesis deals with the application of legal regulations in a particular state-funded institution. The order of researched areas is in accordance with the theoretical part. The method of comparison and study of documents and internal regulations are used for analysing the data.
The primary research has shown that the legal regulations are applied without difficulty. The discovered discrepancy between the used terminology and the terminology in the Civil code does not invalidate legal documents and thus there is no need to mark it as a defect which needs to be fixed. Suggestions for discussion have been made, for which measures were proposed in the concluding part. The suggestions relate to arrangement of employment for a fixed period of time and its change to permanent contract and to allowance from the founder as a financial mean of a state-funded institution.
|
|
Monitoring of surface changes caused by underground mining in the Karviná region
Doležalová, Hana ; Kajzar, Vlastimil
Geodetic monitoring of the Louky locality revealed irregularities in the development of the subsidence depression and it also helped to document the changing terrain due to ongoing reclamation activities. Repeated GNSS measurements recorded not only the size of subsidence of individual points, but also the size and direction of horizontal displacement of these points, which revealed the influence of undermining in the area of interest, and in its surroundings. It turned out that particularly the significant tectonic fault A forms a barrier of the influence of underground mining. The subsidence depression develops differently than the models of the predicted subsidence expected, especially in the area between the tectonic faults X and A. The method of aerial photogrammetry recorded not only the subsidence caused by underground mining, but also the extent and size of the changes caused by the ongoing reclamation of the surface.
Fulltext: content.csg -  PDF
Plný tet: UGN_0464599 - PDF
|
|
Noise, Transport and Structural Properties of High Energy Radiation Detectors Based on CdTe
Šik, Ondřej ; Lazar, Josef (referee) ; Navrátil, Vladislav (referee) ; Grmela, Lubomír (advisor)
Poptávka ze strany vesmírného výzkumu, zdravotnictví a bezpečnostního průmyslu způsobila v posledních letech zvýšený zájem o vývoj materiálů pro detekci a zobrazování vysokoenergetického záření. CdTe a jeho slitina CdZnTe. jsou polovodiče umožnují detekci záření o energiích v rozsahu 10 keV až 500 keV. Šířka zakázaného pásma u CdTe / CdZnTe je 1.46 -1.6 eV, což umožňuje produkci krystalů o vysoké rezistivitě (10^10-10^11 cm), která je dostačující pro použití CdTe / CdZnTe při pokojové teplotě. V mé práci byly zkoumány detektory CdTe/CdZnTe v různých stádiích jejich poruchovosti. Byly použity velmi kvalitní spektroskopické detektory, materiál s nižší rezistivitou a výraznou polarizací, detektory s asymetrií elektrických parametrů kontaktů a teplotně degenerované vzorky. Z výsledků analýzy nízkofrekvenčního šumu je patrný obecný závěr, že zvýšená koncentrace defektů způsobí změnu povahy původně monotónního spektra typu 1/f na spektrum s výrazným vlivem generačně-rekombinačních procesů. Další výrazná vlastnost degenerovaných detektorů a detektorů nižší kvality je nárůst spektrální hustoty šumu typu 1/f se vzrůstajícím napájecím napětí se směrnicí výrazně vyšší než 2. Strukturální a chemické analýzy poukázaly, že teplotní generace detektorů způsobuje difuzi kovu použitého při kontaktování a stopových prvků hlouběji do objemu krystalu. Část mé práce je věnována modifikaci povrchu svazkem argonových iontů a jejímu vlivu na chemické složení a morfologii povrchu.
|
|
Packet Classification Algorithms
Puš, Viktor ; Lhotka,, Ladislav (referee) ; Dvořák, Václav (advisor)
Tato práce se zabývá klasifikací paketů v počítačových sítích. Klasifikace paketů je klíčovou úlohou mnoha síťových zařízení, především paketových filtrů - firewallů. Práce se tedy týká oblasti počítačové bezpečnosti. Práce je zaměřena na vysokorychlostní sítě s přenosovou rychlostí 100 Gb/s a více. V těchto případech nelze použít pro klasifikaci obecné procesory, které svým výkonem zdaleka nevyhovují požadavkům na rychlost. Proto se využívají specializované technické prostředky, především obvody ASIC a FPGA. Neméně důležitý je také samotný algoritmus klasifikace. Existuje mnoho algoritmů klasifikace paketů předpokládajících hardwarovou implementaci, přesto však tyto přístupy nejsou připraveny pro velmi rychlé sítě. Dizertační práce se proto zabývá návrhem nových algoritmů klasifikace paketů se zaměřením na vysokorychlostní implementaci ve specializovaném hardware. Je navržen algoritmus, který dělí problém klasifikace na jednodušší podproblémy. Prvním krokem je operace vyhledání nejdelšího shodného prefixu, používaná také při směrování paketů v IP sítích. Tato práce předpokládá využití některého existujícího přístupu, neboť již byly prezentovány algoritmy s dostatečnou rychlostí. Následujícím krokem je mapování nalezených prefixů na číslo pravidla. V této části práce přináší vylepšení využitím na míru vytvořené hashovací funkce. Díky použití hashovací funkce lze mapování provést v konstantním čase a využít při tom pouze jednu paměť s úzkým datovým rozhraním. Rychlost tohoto algoritmu lze určit analyticky a nezávisí na počtu pravidel ani na charakteru síťového provozu. S využitím dostupných součástek lze dosáhnout propustnosti 266 milionů paketů za sekundu. Následující tři algoritmy uvedené v této práci snižují paměťové nároky prvního algoritmu, aniž by ovlivňovaly rychlost. Druhý algoritmus snižuje velikost paměti o 11 % až 96 % v závislosti na sadě pravidel. Nevýhodu nízké stability odstraňuje třetí algoritmus, který v porovnání s prvním zmenšuje paměťové nároky o 31 % až 84 %. Čtvrtý algoritmus kombinuje třetí algoritmus se starším přístupem a díky využití několika technik zmenšuje paměťové nároky o 73 % až 99 %.
|
guest ::
