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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.
411

Majoritetens tyranni, eller? : En kvantitativ analys av effekten av konstitutionella lagprövningssystem

Björk, Emil January 2019 (has links)
No description available.
412

Nature Routines of Children as Leverage Point for Sustainable Social-Ecological Urbanism : Connecting childhood and biosphere to design sustainable civilizations in the human habitat

Giusti, Matteo January 2016 (has links)
Strong sustainability requires enhanced knowledge and understanding of complex social-ecological interactions, but it also implies a ‘novel’ conceptualization of the relationship between humans and nature, one in which individuals perceive themselves as embedded members of the Biosphere. The aim of this Licentiate thesis is to investigate the validity of a strategy that is centered on designing the urban green infrastructure to nurture such human-nature relationship in children’s attitudes. The research is framed by spatial cognition, conservation psychology, and social-ecological sustainability and it focuses on the validity of this strategy. Hence, the Licentiate analyzes how reoccurring experiences of nature that are situated in the everyday habitat (i.e. nature routines) affect personal human-nature attitudes and how these can be implemented as leverage points to change social-ecological systems using sustainable urbanism. Paper 1 tests the assumed link between the nature routines in Stockholm and preschool children’s development of cognitive and emotional affinity to nature. The results show that nature-rich routines over a period of four years are significantly correlated with the strength of preschooler’s affinity with nature. Paper 2 uses a mixed methods approach to evaluate changes in Connection To Nature (CTN) in 10 years olds who partake in a project of nature conservation. The results of Paper 2 show that there is an evaluative gap between theory and practice in connecting children with nature that impedes the evaluation of how children’s CTN changes over short periods of time and that impedes the creation of an evaluative framework for nature experiences. Paper 3 considers these empirical results in theorizing an approach to sustainable urban design based on social-ecological sustainability that includes CTN. In order to overcome existing limitations Paper 3 presents the concept of cognitive affordances as a theoretical tool to embed cognitive and emotional attitudes towards nature into the design of urban spaces. All combined these papers provide valid evidence that nature routines in cities, especially for children, can be a significant leverage point to enable future sustainable civilizations.
413

New methods for the ab-initio simulation of correlated systems

Schade, Robert 29 January 2019 (has links)
No description available.
414

Long range dependence v časových řadách / Long range dependence in time series

Till, Alexander January 2014 (has links)
Title: Long range dependence in time series Author: Alexander Till Department: Department of Probability and Mathematical Statistics Supervisor: RNDr. Michaela Prokešová, Ph.D. Abstract: The diploma thesis demonstrates the necessity of a study of long range dependence, introduces fractional Gaussian noise and discusses possible definitions of long memory. It is done by notions of ergodic theory and by second moment characteristics and spectral density. These definitions are confronted with the model of fractional Gaussian noise and with intuitive understanding of long range memory. Relations and connections between these criteria are studied as well. The work is restricted to the study of discrete time processes. 1
415

Long range dependence v časových řadách / Long range dependence in time series

Till, Alexander January 2016 (has links)
Title: Long range dependence in time series Author: Alexander Till Department: Department of Probability and Mathematical Statistics Supervisor: RNDr. Michaela Prokešová, Ph.D. Abstract: The diploma thesis demonstrates the necessity of a study of long range dependence, introduces fractional Gaussian noise and discusses possi- ble definitions of long memory. It is done by notions of ergodic theory and by second moment characteristics and spectral density. These definitions are confronted with the model of fractional Gaussian noise and with intuitive un- derstanding of long range memory. Relations and connections between these criteria are studied as well. The work is restricted to the study of discrete time processes. Method for Hurst index estimation for fractional Gaussian noise and it's application on logarithmic returns of shares of selected produ- cers of beer are included in this work. 1
416

Elektronová struktura a magnetické vlastnosti materiálů se silně korelovanými elektrony / Electronic structure and magnetic properties of the materials with strong electron-electron correlation

Kozub, Agnieszka Lidia January 2018 (has links)
In this thesis, we summarize the material-specific theories of strongly correlated systems and apply them to selected materials. We describe and apply the corre- lated band theory methods: the local density approximation plus Coulomb U, and the density functional theory plus exact diagonalization of single impurity An- derson model. First, we investigate the systems containing impurity atoms: cobalt impurity located in the bulk copper and samarium, and neodymium adatoms on the surface of graphene. We present the spectral densities and study the magnetism of those compounds. Afterwards, we analyze three Np-based compounds: NpPt2In7, Np2Ni17 and NpBC. For all three compounds we analyze the spin, orbital and to- tal magnetic moments and the total density of states, as well as its projections for selected orbitals and spins. Moreover, for NpPt2In7 and NpBC we perform the to- tal energy analysis between different magnetic moment arrangements on the Np atoms.
417

Zajištění bezpečnosti online platebních služeb / Ensuring security of online payment services

Havlíková, Nikola January 2019 (has links)
Ensuring security of online payment services Abstract The thesis is devoted to the topic of ensuring security of online payment services, especially in the context of identification and authentication of the client in the Internet when performing acts related to the provision of payment services. The issue of the customer identity is described especially in the context of know your customer principle governed by legal regulation in the area of combating money laundering and financing of terrorism, and in the context of the obligation to carry out a strong customer authentication (SCA) brought by the PSD2 directive and related RTS. The aim of the thesis is to describe and critically evaluate the legislation in the area of ensuring security of online payment services, meaning the binding legislation, soft law and rules created by entities operating on the payment services market. In this context, the thesis also deals with the question of proportionality of legislation in connection to the positive user experience and the possibility of implementing innovative FinTech solutions. The thesis is divided into four chapters, supplemented by introduction to the respective subject matter and conclusion summarizing the observations made in the thesis. The first chapter is devoted to the general definition of the...
418

Mid-Infrared Detectors and THz Devices Operating in the Strong Light-Matter Coupling Regime / Détecteurs moyen infrarouge et dispositifs THz en régime de couplage fort entre lumière et matière

Vigneron, Pierre-Baptiste 15 April 2019 (has links)
Les polaritons inter-sous-bandes, observés pour la première fois il y a une quinzaine d’années, sont des quasi-particules dont de nombreuses propriétés restent encore à découvrir. La recherche dans ce domaine se focalise actuellement sur la réalisation de condensats de Bose-Einstein. Une telle découverte pourrait révolutionner l’optoélectronique du moyen infra-rouge jusqu’au THz ouvrant la voie à l’instauration de nouveaux concepts de sources lumineuses,de détecteurs ou de systèmes logiques en couplage fort. Dans cette quête, le choix de la cavité résonnante est critique. Dans ce manuscrit nous proposons d’utiliser des cavités métal-isolant-métal (M-I-M) avec un réseau dispersif sur le métal supérieur. Ce type de cavité,conservant un confinement élevé entre les deux plans métalliques, offre de nombreuses possibilités d’ajustement de la résonance de cavité : via la géométrie de la cavité ( épaisseur de la cavité, période et recouvrement du réseau) ainsi que par le couplage de la lumière avec la cavité (vecteur d’onde incident). Les cavités M-I-M dispersives ouvrent donc un nouveau champ d’exploration des polaritons inter-sous-bande. Dans un premier temps nous avons introduit ces cavités dans le domaine du THz afin d’étudier les phénomènes de relaxation polariton-polariton. Un système expérimental dédié à cette exploration a été conçu pour mesurer la réflectivité des polaritons THz avec une fine résolution en angle. Dans une second temps, des capteurs moyen infrarouge en couplage fort avec une cavité M-I-M dispersive ont été conçus, fabriqués et mesurés dans le but d’explorer la génération de photo-courant à partir de polaritons et d’utiliser le couplage fort pour dissocier l’ énergie de détection de l’énergie d’activation. Cette seconde étude s’inscrit dans l’objectif de pompage électrique des polaritons ISB. Parallèlement à l’étude des polaritons, nous avons également participé au développement de techniques(interféromètre Gires-Tournois et revêtement anti-réflection) pour compresser les impulsions optiques de lasers à cascade quantique THz. / After fifteen years of intersubband polaritons development some of the peculiar properties of these quasi-particles are still unexplored. A deeper comprehension of the polaritons is needed to access their fundamental properties and assess their applicative potential as efficient emitters or detectors in the mid-infrared and THz.In this manuscript we used Metal-Insulator-Metal (MI-M) cavities with a top metal periodic grating as a platform to deepen the understanding of ISB polaritons.The advantages of M-I-M are twofold : first they confine the TM00 mode, second the dispersion of the cavity -over a large set of in-plane wave-vectors- offers various experimental configurations to observe the polaritons in both reflection and photo-current. We reexamined the properties of ISB polaritons in the mid-infrared and in the THz using these resonators. In the first part, we explore the implementation of dispersive M-I-M cavities with THz intersubband transitions. In the THz domain, the scattering mechanisms of the THz ISB polaritons need to be understood. The dispersive cavity is a major asset to study these mechanisms because it provides more degrees of freedom to the system. For this purpose, we fabricated a new experimental set-up to measure the polariton dispersion at liquid Helium temperature. After the characterization of the polaritons in reflectivity, a pump-probe experiment was performed on the polaritonic devices. The second part of this manuscript presents the implementation of M-I-M dispersive cavities with abound-to-quasi-bound quantum well infrared photo detector designed to detect in strong coupling. Beyond electrical probing of the polaritons, the strong coupling can disentangle the frequency of detection from the thermal activation energy and reduce the dark current at a given frequency. In parallel to the exploration of THz polaritons, we developed two techniques (Gires-Tournois Interferometer and Anti-reflection coating) in order to shorten the pulses of THz quantum cascade lasers with metal-metal waveguides.
419

Finances in Strong African American Marriages

Anderson, Bonnie Lichfield 01 December 2010 (has links)
This study focused on how African American couples in happy marriages talked about finances in their couple relationships. Qualitative methodology was used for this study, and the data came from transcribed interviews with participants. Thirty-seven couples who identified their marriages as being strong, happy, or highly satisfying, volunteered to be interviewed for this study. All individual participants (74 total) talked about finances in their marriages, and all interviews were used for the purpose of this study. Their descriptions were coded and analyzed to explore the way that they talked about money issues in their marriages. The research questions focused on how couples talked about financial stress and how they talked about financial decisions in their relationships. An unanticipated finding was how they talked about transcending finances in their marriages. The findings can contribute to future research and financial education for African American couples.
420

Parametry uspořádání tříflavourové chirální symetrie z ππ rozptylu / Order parameters of three-flavour chiral symmetry from ππ scattering

Říha, Jaroslav January 2021 (has links)
This thesis familiarizes the reader with the process behind the construction of ππ scattering amplitudes. Several representations and transformations nec- essary to pass from one to another are introduced. Then known solutions of Roy equations are employed to extract values of subthreshold parameters αππ and βππ from recent experimental data. As a second goal three-flavour chiral perturbation theory(χPT), which is a low energy effective field theory of quan- tum chromodynamics, is used to obtain theoretical predictions for αππ and βππ by applying a technique called resummed approach. A large statistical ensemble of predictions is numerically generated. Subsequently, Bayesian statistics is uti- lized to get more information about spontaneous symmetry breaking parameters X(3), Y (3), Z(3), which are related to the leading order low energy coupling constants of three-flavour χPT. These results are then compared to several other recent determinations. Significant shifts in probability distributions compared to Descotes-Genon et al. [2004] are observed. The new results are more consistent with theoretical expectations. 1 Bibliography S. Descotes-Genon, N. H. Fuchs, L. Girlanda, and J. Stern. Resumming qcd vac- uum fluctuations in three-flavor chiral perturbation theory. The European Phys- ical Journal C,...

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