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  • About
  • The Global ETD Search service is a free service for researchers to find electronic theses and dissertations. This service is provided by the Networked Digital Library of Theses and Dissertations.
    Our metadata is collected from universities around the world. If you manage a university/consortium/country archive and want to be added, details can be found on the NDLTD website.
461

Studie rekonstrukce železniční stanice Zruč nad Sázavou / Upgrading of Zruč nad Sázavou Railway Station

Hřib, Oldřich January 2015 (has links)
Primary objective of diploma thesis is design geometrical parameters of tracks at railway station Zruč nad Sázavou for three new platforms with acces options for paralyzed people and preservetion four railway tracks. Other objective is proposition of track drainage and reconstruction superstructure and substructure
462

Studie úrovňové křižovatky I/45 a I/11 v Bruntále / The study level crossings I / 45 and I / 11 in Bruntal

Kufka, Jiří January 2017 (has links)
The subject of my Master’s thesis is the variant redevelopment of level crossings I/45 and I/11 nearby bus terminal in Bruntál in Moravian-Silesian region. The current design isn’t well arranged and the crossroad is place of frequent traffic accidents. There are four solutions of existing crossroad. In the frame of variants, there is a different manner of solution of structural layout of crossroad, possibility of connection of shopping center and solution of pedestrian traffic. The thesis includes traffic survey, evaluation of accidents, capacity analysis of existing crossroad and four new solutions and estimate of building costs.
463

Návrh rekonstrukce železničních stanic Šternberk a Bohuňovice / Design of reconstruction of railway stations Šternberk nad Bohuňovice

Šatánek, Jan January 2017 (has links)
The design of reconstruction of railway stations Šternberk and Bohuňovice comprises the proposal to increase the line speed of the main track to the maximum possible value, the design of station tracks and reconstruction of railway switches and crossings, the design of the new platforms, which implements the requirements for people with reduced mobility and the design of new drainage system. Next, the design of reconstruction comprises the design of the railway superstructure and substructure and the design of railway level crossings.
464

Rekonstrukce železniční stanice Veselí nad Moravou / Veseli Nad Moravou Station Reconstruction

Klar, Vít January 2017 (has links)
The subject of the Master's thesis is to design the redevelopment of the Veseli nad Moravou railway station. This renovation will include renewal of both, railway superstructure and substructure, including drainage system and new platform construcion proposal in order to meet current legislation regarding access of persons with reduced mibility and orientation skills. This thesis also deals with design of the track geometry compoments and geometry of set of switches at both heads of the railway station to fulfill the maximum train velocity demands at certain tracks. Last but not least, the rail track scheme of the station has been simplified.
465

Práce v neziskovém sektoru jako další kariérní výzva / Working in non-profit sector as a new career challenge

Nováková, Michaela January 2016 (has links)
This work is aimed to find out what are the motives of people to cross from for-profit to non- profit sector and what life experiences and opinions of those who work in both sectors are. The work examines whether the sectors are different (and how) and whether they can feel some change after being and working in both sectors. Conceptual section places the issue in a broader context, which presents key concepts related to the topic. This explained through the literature, while also bringing some research on work motivation. In the empirical part I analyze the testimony of five respondents, with analysis divided into four thematic blocks. I analyze here the start of their careers, how they feel about career as a word, what means to them. After that I analyze their motives to cross from for-profit to the nonprofit sector, as well as their own comparison between the two sectors. In the last part of my work I slightly analyze their philosophy of life and I also ask about the career and how they think their career could continue. In other chapters, I bring my research results and their comparison with the submitted literature.
466

Mezi Nostalgií a Pragmatismem: 'Hraniční Trilogie' Cormaca McCarthyho. / Between Nostalgia and Pragmatism: Cormac McCarthy's 'Border Trilogy.'

Polívka, Zdeněk January 2019 (has links)
THESIS ABSTRACT This thesis deals with the problematics and the role of American frontier and American West in Cormac McCarthy's border trilogy consisting of All the Pretty Horses (1992), The Crossing (1994) and Cities of the Plain (1999). The reading proper focuses mainly on the second novel of the trilogy, making frequent references to both the other two volumes of the trilogy and to Blood Meridian (1985), a novel directly preceding the trilogy itself. The main goal of the thesis is to demonstrate that the trilogy not only critically engages with the American nationalist ideology represented by a nostalgically conceptualized myths of the American frontier, but that it also offers its own alternative vision of the concept of the frontier and of American national identity. The thesis further claims that McCarthy's critical approach to the mythical representations of the American history bears strong resemblance to the philosophy of American pragmatism as defined by a French philosopher Giles Deleuze in his works dedicated to American thinking and culture. In his pragmatic view of American identity the frontier ceases to function in its traditional, nationalistic sense as a line of separation that divides the social and political space into binary categories, and instead it is understood as an open and...
467

Teoretická studie vlivu spin-orbitální interakce na spektra a fotofyziku rheniových komplexů / Theoretical study of spin-orbit coupling on spectra and photophysics of rhenium complexes

Heydová, Radka January 2017 (has links)
Title: Theoretical study of spin-orbit coupling on spectra and photophysics of rhenium complexes Author: RNDr. Radka Heydová Department: Physical and Macromolecular Chemistry Supervisor: Ing. Stanislav Záliš, CSc., JHI AS CR, v.v.i. Supervisor's e-mail address: stanislav.zalis@jh.inst-cas.cz Abstract: Relativistic effects, especially spin-orbit coupling (SOC), play an essential role in transition metal chemistry and SOC treatment is indispensable for a correct theoretical description. To demonstrate the importance of SOC, the energies and oscillator strengths of vertical transitions for a series of [ReX(CO)3(2,2'-bipyridine)] (X = Cl, Br, I) and [Re(imidazole)(CO)3(1,10-phenanthroline)]+ complexes were calculated in the spin-free (SF) and spin-orbit (SO) conceptual frameworks. Two different computational approaches were adopted: SO-MS-CASPT2 where SOC was added a posteriori using a configuration interaction model (SO-RASSI), and the approximate perturbative SO-TD-DFT method. Relativistic effects were included via the two-component Douglas-Kroll-Hess transformation and the zeroth-order regular approximation in the former and the latter technique, respectively. The SF (i.e. accounting only for the scalar relativistic effects) and SO results from both methods were compared with each other and to available...
468

Mutation and Genome Evolution

Yampolsky, L. Y. 14 April 2016 (has links)
Genome composition and architecture is shaped by two types of processes: those that introduce heritable changes (mutagenesis) and those that determine the fate of such changes in the populations (genetic drift and selection). Chemical and biological properties of mutagenesis determines the frequencies at which different type of mutations occur, which, in turn, determines their rates of fixation by drift and affects the spectrum of mutations available for selection to operate on. As the result, genomes of living organisms carry many signatures mutagenesis.
469

Hur påverkar en ökad belysningsstyrka på övergångsställen bilisters hastighet? / How an increased illuminance at pedestrian crossing affects the speed of vehicles?

Karlsson, Anton, Hjorth, Alexander January 2020 (has links)
Syftet med studien var att undersöka hur en ökad belysningsstyrka på övergångsställen påverkar bilisters hastighet. Vid vissa övergångsställen används idag intensivbelysning. Intensivbelysning innebär att belysningen förstärkts vid platsen och utformas av en eller flera armaturer över eller i anknytning till övergångsställen för att öka synbarheten för fotgängare. Målet med studien är att undersöka om en ökad belysningsstyrka på övergångsställen har en positiv eller en negativ påverkan på bilisters hastighet och därför kunna bidra till en ökad kunskap inom trafiksäkerhet. För att undersöka hur intensivbelysning påverkar bilisters hastighet har hastighetsmätningar utförts på två övergångsställen i centrala Jönköping samt vid en kontrollplats. Hastighetsmätningarna utfördes på en urban väg med en hastighetsbegränsning på 40 km/h. mätningarna utfördes under perioden 2020-03-16 – 2020-03-24. Det ena övergångsstället har intensivbelysning det andra har det inte, för att kunna jämföra de två platserna utfördes mätningar av både luminans och belysningsstyrka. Övergångsstället med intensivbelysning benämnt som observationsplats 1, hade en medelbelysningsstyrka på 73,27 lux och en medelluminans på 2,7 cd/m². Övergångsstället utan intensivbelysning benämnt som observationsplats 2, hade en medelbelysningsstyrka på 15.63 lux och en medelluminans på 1,3 cd/m². Det skiljer alltså 57,64 lux i medelbelysningsstyrka mellan observationsplats 1 och observationsplats 2, och 1,4 cd/m² i medelluminans. Vid observationsplats 1 uppmättes dagtid 10 passager. Vilket resulterade i en medelhastighet på 35,7 km/h (standardavvikelse 4,6 km/h). Kvällstid uppmättes 35 passager. Vilket resulterade i en medelhastighet på 37,49 km/h (standardavvikelse 5,3 km/h). Vid observationsplats 2 uppmättes dagtid 10 passager. Vilket resulterade i en medelhastighet på 40 km/h (standardavvikelse 4 km/h). Kvällstid uppmättes 34 passager. Vilket resulterade i en medelhastighet på 36 km/h (standardavvikelse 4 km/h). Resultatet från studien antyder att intensivbelysning vid övergångsställen leder till en högre fordonshastighet. Skillnaden i medelhastighet mellan observationsplats 1 och observationsplats 2 var låg 1,49 km/h, standardavvikelsen var hög (observationsplats 1 5,3 km/h observationsplats 2 4 km/h).
470

Modélisation et simulation de l’écoulement diphasique dans les moteurs-fusées à propergol solide par des approches eulériennes polydispersées en taille et en vitesse / Eulerian modeling and simulation of two-phase flows in solid rocket motors taking into account size polydispersion and droplet trajectory crossing

Dupif, Valentin 22 June 2018 (has links)
Les gouttes d’oxyde d’aluminium présentes en masse dans l’écoulement interne des moteurs-fusées à propergol solide ont tendance à influerde façon importante sur l’écoulement et sur le fonctionnement du moteur quel que soit le régime. L’objectif de la thèse est d’améliorerles modèles diphasiques eulériens présents dans le code de calcul semi-industriel pour l’énergétique de l’ONERA, CEDRE, en y incluant lapossibilité d’une dispersion locale des particules en vitesse en plus de la dispersion en taille déjà présente dans le code, tout en gardant unestructure mathématique bien posée du système d’équations à résoudre. Cette nouvelle caractéristique rend le modèle capable de traiter lescroisements de trajectoires anisotropes, principale difficulté des modèles eulériens classiques pour les gouttes d’inertie modérément grande.En plus de la conception et de l’analyse détaillée d’une classe de modèles basés sur des méthodes de moments, le travail se concentre sur larésolution des systèmes d’équations obtenus en configurations industrielles. Pour cela, de nouvelles classes de schémas précis et réalisables pourle transport des particules dans l’espace physique et l’espace des phases sont développées. Ces schémas assurent la robustesse de la simulationmalgré différentes singularités (dont des chocs, -chocs, zones de pression nulle et zones de vide...) tout en gardant une convergence d’ordredeux pour les solutions régulières. Ces développements sont conduits en deux et trois dimensions, en plus d’un référentiel bidimensionnelaxisymétrique, dans le cadre de maillages non structurés.La capacité des schémas numériques à maintenir un niveau de précision élevé tout en restant robuste dans toutes les conditions est un pointclé pour les simulations industrielles de l’écoulement interne des moteurs à propergol solide. Pour illustrer cela, le code de recherche SIERRA,originellement conçu durant les année 90 pour les problématiques d’instabilités de fonctionnement en propulsion solide, a été réécrit afin depouvoir comparer deux générations de modèles et de méthodes numériques et servir de banc d’essais avant une intégration dans CEDRE. Lesrésultats obtenus confirment l’efficacité de la stratégie numérique choisie ainsi que le besoin d’introduire, pour les simulations axisymétriques,une condition à la limite spécifique, développée dans le cadre de cette thèse. En particulier, les effets à la fois du modèle et de la méthodenumérique dans le contexte d’une simulation de l’écoulement interne instationnaire dans les moteurs-fusées à propergol solide sont détaillés.Par cette approche, les liens entre des aspects fondamentaux de modélisation et de schémas numériques ainsi que leurs conséquences pour lesapplications sont mis en avant. / The massive amount of aluminum oxide particles carried in the internal flow of solid rocket motors significantly influences their behavior.The objective of this PhD thesis is to improve the two-phase flow Eulerian models available in the semi-industrial CFD code for energeticsCEDRE at ONERA by introducing the possibility of a local velocity dispersion in addition to the size dispersion already taken into accountin the code, while keeping the well-posed characteristics of the system of equations. Such a new feature enables the model to treat anisotropicparticle trajectory crossings, which is a key issue of Eulerian models for droplets of moderately large inertia.In addition to the design and detailed analysis of a class of models based on moment methods, the conducted work focuses on the resolution ofthe system of equations for industrial configurations. To do so, a new class of accurate and realizable numerical schemes for the transport ofthe particles in both the physical and the phase space is proposed. It ensures the robustness of the simulation despite the presence of varioussingularities (including shocks, -shocks, zero pressure area and vacuum...), while keeping a second order accuracy for regular solutions. Thesedevelopments are conducted in two and three dimensions, including the two dimensional axisymmetric framework, in the context of generalunstructured meshes.The ability of the numerical schemes to maintain a high level of accuracy in any condition is a key aspect in an industrial simulation of theinternal flow of solid rocket motors. In order to assess this, the in-house code SIERRA, originally designed at ONERA in the 90’s for solidrocket simulation purpose, has been rewritten, restructured and augmented in order to compare two generations of models and numericalschemes, to provide a basis for the integration of the features developed in CEDRE. The obtained results assess the efficiency of the chosennumerical strategy and confirm the need to introduce a new specific boundary condition in the context of axisymmetric simulations. Inparticular, it is shown that the model and numerical scheme can have an impact in the context of the simulation of the internal flow ofsolid rocket motors and their instabilities. Through our approach, the shed light on the links between fundamental aspects of modeling andnumerical schemes and their consequences on the applications.

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