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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.
71

Cautious Romantics: Trinitarian Transcendentalists and the emergence of a conservative religious tradition in America

Koefoed, Jonathan George 22 January 2016 (has links)
The American Transcendentalists are often equated with Romanticism in nineteenth-century America. This dissertation thoroughly complicates that equation, arguing that a group of "Cautious Romantics" emerged as an alternative and conservative Romantic religious tradition. Drawing on history, art history, philosophy, literature, and theology, this dissertation provides a much fuller picture of the way European Romantic texts and authors functioned in American intellectual, cultural, and religious history by highlighting the contribution of these Cautious Romantics. Taken together, the Cautious Romantics represented a distinct religious discourse. They were American Romantics: relentless and introspective questers who emphasized epistemological intuition, artistic inspiration, and spiritual experience. In fact, some of them were the first Americans to promote European Romantic influences. Nevertheless, the Cautious Romantics continued to embrace Trinitarian Christianity, and they celebrated institutions--colleges and churches--in contrast to the often anti-institutional temperament of the Transcendentalists. Moreover, the Cautious Romantics defied religious categorization among standard antebellum groups. They were neither evangelicals, nor traditional Congregationalists, nor Unitarians. Although many became Episcopalians or Catholics, their Romantic intellectual lineage and historical relationships with one another distinguished them from their denominational kindred. Functioning on two levels, this dissertation resituates several well-known American artists and intellectuals such as Washington Allston, Orestes Brownson, Richard Henry Dana Jr., and Harriet Beecher Stowe by connecting them historically and intellectually with a wider discourse. This dissertation also unearths or re-contextualizes numerous lesser-known religious intellectuals such as Richard Henry Dana Sr., James Marsh, Sophia Dana Ripley, George Allen, Henry Hope Reed, Gulian Verplanck, Leonard Woods Jr., and Isaac Hecker. While conservative, these intellectuals were neither committed to the antebellum American South's unique conservative vision nor did they celebrate the free-market conservatism common in twentieth-century America. Thus, in addition to its contribution to intellectual and religious history, this dissertation contributes to a growing body of literature on cultural conservatism in America. Moreover, although the Cautious Romantics were American, this dissertation highlights the important historical relationships between the Cautious Romantics and Coleridge, Wordsworth, the Roman Catholic Church, and, in Harriet Beecher Stowe's case, transatlantic social reform, thereby demonstrating the transatlantic nature of Romanticism in the nineteenth century.
72

Inversion acoustique tridimensionnelle des formes d'onde complètes : méthodes algorithmes et application au réservoir pétrolier de Valhall / Three-dimensional acoustic Full Waveform Inversion : method, algorithms and application to the Valhall petroleum field

Hu, Guanghui 21 September 2012 (has links)
L'imagerie quantitative des propriétés physiques du sous-sol est fondamentale pour de nombreuses applications impliquant des échelles d'exploration très variées: géotechnique pour l'imagerie de la proche surface, exploration à l'echelle crustale, reconstruction lithosphérique et imagerie globale pour la compréhension fondamentale des processus géodynamiques, mais aussi pour l'exploitation optimale des ressources du sous-sol.Parmi les méthode géophysiques, les méthodes sismiques ont le pouvoir de résolution le plus élevé. La densification des dispositifs d'acquisition, la mise au point de sources et de capteurs large bande et l'augmentation de la puissance de calcul ouvrent de nouvelles perspectives pour le développement et l'application de méthodes non conventionnelles d'imagerie sismique pour une extraction plus complète de l'information contenue dans les données sismiques. Parmi ces méthodes d'imagerie non conventionnelles, les méthodes d'inversion du champ d'onde complet, fondées sur la résolution complète de l'équation d'onde pour le problème direct (modélisation sismique) et la résolution d'un processus d'optimisation pour le problème inverse, font actuellement l'objet de nombreux développements méthodologiques, tant au sein des communautés industrielles qu'académiques.Le challenge numérique est la résolution du problème direct en trois dimensions pour un grand nombre de sources sismiques caractéristique des acquisitions pétrolières massives, et le challenge méthodologique est la gestion de la non-linéarité du problème inverse résultant de l'éclairage incomplet du sous-sol depuis la surface par des sources de bande-passante limitée. L'apport attendu de ces méthodes est la résolution de l'imagerie sismique de l'ordre de la demi-longueur d'onde propagée, sa capacité à imager des cibles complexes d'un point de vue structural notamment sous des écrans salifères ou basaltiques et la quantification des paramètres physiques caractérisant le sous-sol tels que la vitesse de propagation des ondes de compression à laquelle peuvent s'ajouter la densité, l'atténuation, la vitesse de propagation des ondes de cisaillement et des paramètres caractérisant l'anisotropie du milieu.L'objectif de cette thèse est de poursuivre le développement d'une méthode d'imagerie sismique acoustique 3D par l'inversion du champ d'onde complet et de l'appliquer à des données réelles pétrolières 3D de fond de mer enregistrées sur le champ pétrolier de Valhall en Mer du Nord et de fournir une des premières évaluations du potentiel des méthodes d'inversion des formes d'onde pour l'imagerie de milieux géologiques 3D L'inversion est effectuée en domaine fréquentiel où un nombre limité de fréquences est inversé suivant un protocole hiérarchique maintenant bien éprouvé procédant des basses fréquences vers les hautes fréquence: cette approche multi-échelle favorise la prise en compte de la non-linéarité du problème inverse.L'approche de modélisation en domaine temporel avec extraction du champ monochromatique par une transformée de Fourier discrète est effectuée pour calculer les champs d'onde monochromatique nécessaires à la résolution du problème inverse. L'algorithme d'optimisation du problème inverse est fondé sur une méthode de gradients conjugués préconditionés ou sur une méthode quasi-Newton. Les méthodes sont appliquées dans le cadre de l'approximation visco-acoustique isotrope où le milieu est paramétré par la vitesse de propagation des ondes de compression, l'atténuation et la densité. Seule, la composante hydrophone acquise en fond de mer est inversée. L'enjeu méthodologique de cette thèse est de fournir un modèle tri-dimensionelle du champ pétrolier de Valhall dans un cube de dimensions approximatives 18 km x 12 km x 5 km en poussant l'inversion à la fréquence la plus élevée possible. / Quantitative imaging of the subsurface physical properties is fundamental to many applications involving very various explorations, such as geotechnical imaging of the near surface, petroleum exploration, crustal lithospheric exploration. This helps us to understand the fundamental of geodynamic processes and also to exploit the resources of subsurface. Among the geophysical methods, seismic methods can give a higher resolution. The improvements of the acquisition in size and density, the multifold/multicomponent wide-aperture and wide-azimuth acquisitions, and the increased high-performance computing power open new perspectives to develop and apply non-conventional seismic imaging methods for extraction more complete and continuous information in the seismic data. Among these non-conventional methods, the full waveform inversion method based on the complete resolution of the wave equation for the direct problem (seismic modeling) and the resolution of optimization process for the inverse problem, are currently the subject of many methodological developments, in both industrial and academic communities. The numerical challenge is the resolution of the three-dimensional direct problem for a large number of seismic sources, typically few to tens of thousands in petroleum industry acquisition. The methodological challenge is the management of the non-linearity of the inverse problem resulting from the incomplete illumination of subsurface from the surface survey with a limited bandwidth source. The expected contribution of these methods is to reach a spatial resolution of half-a-wavelength. It has the ability to image complex structure targets such as saline or salt-bearing basaltic and to quantify the subsurface physical parameters such as velocity, density, attenuation, anisotropic parameters and so on. The objective of this thesis is to develop a method of three-dimensional seismic imaging by full waveform inversion and apply it to real ocean-bottom data set recorded in the Valhall oil field (in the North Sea) and to provide an early evaluation of the potentialities of full waveform inversion for imaging three-dimensional geological environments . The inversion is performed in frequency domain. A limited number of frequencies is inverted following a hierarchical protocol from low to high frequencies. This multi-scale approach helps to reduce the non-linearity of the inverse problem. The modeling approaches is performed in time domain and monochromatic wavefields are extracted by discrete Fourier transform to solve the inverse problem in frequency domain. The optimization algorithm of the inverse problem is based on conjugate gradients method or quasi-Newton method. The method is applied in the framework of the visco-acoustic isotropic approximation, where the medium is parameterized by the velocity of compressional wave propagation, attenuation, and density. The hydrophone data component located at the seabed is inverted. The methodological issue of this thesis is to develop by full waveform inversion a three-dimensional high-resolution velocity model of the Valhall oil field in a cube with a size of 18 km $\times$ 12 km $\times$ 5 km, and to push the inversion towards frequencies as high as possible.
73

Mobilizing Victimhood: Blaming and Claiming the Victim in Conservative Discourse in Canada

Gordon, Kelly 22 June 2018 (has links)
When it comes to the politics of victimhood, existing academic accounts contend that conservative politics and ideology have largely been defined by a backlash against discourses of victimization. In this respect, North American conservatism is seen as embodying an anti-victimist approach – one where progressive claims of victimhood are represented as the result of an impaired character rather than as the result of systemic cultural and legal discrimination. However, while this literature accurately captures many characteristics of conservative ideology, it risks overlooking the ways that conservative proactively engage with the politics of victimhood and victim arguments. This dissertation offers an examination of the discursive significance of the “victim” in contemporary conservative politics and ideology through an analysis of three realms of conservative politics in Canada: (1) the men’s rights movement, (2) the anti-abortion movement, and (3) the Conservative Party of Canada. Drawing on the results of a large-scale critical discourse analysis and the participant observation of over a dozen conservative events in Canada, this dissertation contends that the debate over the politics of victimhood is not a battle between anti-victim conservative and pro-victim progressives. Rather, contemporary Canadian conservatives are increasingly makers of victim politics – rather than its critics – challenging many academic assumptions made about both conservative ideology and discourse in Canada, as well as the larger politics of victimhood in North America.
74

Discrétisations spatiales de systèmes dynamiques génériques / Spatial discretizations of generic dynamical systems

Guihéneuf, Pierre-Antoine 26 June 2015 (has links)
Dans quelle mesure peut-on lire les propriétés dynamiques (quand le temps tend vers l’infini) d’un système sur des simulations numériques ? Pour tenter de répondre à cette question, on étudie dans cette thèse un modèle rendant compte de ce qui se passe lorsqu’on calcule numériquement les orbites d’un système à temps discret f (par exemple un homéomorphisme). L’ordinateur travaillant à précision numérique finie, il va remplacer f par une discrétisation spatiale de f, notée f_N (où l’ordre de la discrétisation N rend compte de la précision numérique). On s’intéresse en particulier au comportement dynamique des applications finies f_N pour un système f générique et pour l’ordre N tendant vers l’infini, où générique sera à prendre dans le sens de Baire (principalement parmi des ensembles d’homéomorphismes ou de C^1-difféomorphismes). La première partie de cette thèse est consacrée à l’étude de la dynamique des discrétisations f_N lorsque f est un homéomorphisme conservatif/dissipatif générique d’une variété compacte. L’étude montre qu’il est illusoire de vouloir retrouver la dynamique du système de départ f à partir de celle d’une seule discrétisation f_N : la dynamique de f_N dépend fortement de l’ordre N. Pour détecter certaines dynamiques de f il faut considérer l’ensemble des discrétisations f_N, lorsque N parcourt N.La seconde partie traite du cas linéaire, qui joue un rôle important dans l’étude du cas des C^1-difféomorphismes génériques, abordée dans la troisième partie de cette thèse. Sous ces hypothèses, on obtient des résultats similaires à ceux établis dans la première partie, bien que plus faibles et de preuves plus difficiles. / How is it possible to read the dynamical properties (ie when the time goes to infinity) of a system on numerical simulations ? To try to answer this question, we study inthis thesis a model reflecting what happens when the orbits of a discrete time system f (for example an homeomorphism) are computed numerically. The computer working in finite numerical precision, it will replace f by a spacial discretization of f, denotedby f_N (where the order N of discretization stands for the numerical accuracy). In particular, we will be interested in the dynamical behaviour of the finite maps f_N for a generic system f and N going to infinity, where generic will be taken in the sense of Baire (mainly among sets of homeomorphisms or C^1-diffeomorphisms). The first part of this manuscript is devoted to the study of the dynamics of the discretizations f_N, when f is a generic conservative/dissipative homeomorphism of a compact manifold. We show that it would be mistaken to try to recover the dynamics of f from that of a single discretization f_N : its dynamics strongly depends on the order N. To detect some dynamical features of f we have to consider all thediscretizations f_N when N goes through N.The second part deals with the linear case, which plays an important role in the study of C^1-generic diffeomorphisms, discussed in the third part of this manuscript. Under these assumptions, we obtain results similar to those established in the first part,though weaker and harder to prove.
75

Är Sverigedemokraterna ett Högerradikalt populistiskt parti eller Socialkonservativt? : En undersökning av partimaterialet utifrån två idealtyper. / The Sweden Democrats a radical right-wing populist party or Socialconservatives? : A study of the party documents based on two ideal types.

Tengdelius, Daniel January 2019 (has links)
The political party Sweden democrats became Sweden’s third largest party in 2014 after entering the Swedish parliament back in 2010 for the first time. During this time discussions about the party background and ideology have increased both from other parties and in the society. The controversy surrounding the party can partly be traced back to its foundation and the period before the party entered the national parliament in 2010. Sweden democrats was founded in 1988 by the remains of two right wing extremist movements, today the party has distanced itself from Nazism and calls itself a social conservative party. According to studies Sweden democrat’s ideology is considered as right-wing radical populism. This difference of identification is a problem, because it creates questions why it exists. Are the Sweden democrats really a social conservative party or is the party rendering a false image, and why. In this essay I will use ideal types of the two ideologies social conservative and Right-wing radical populism to evaluate which ideal type can describe the ideology in the party materials of the Swedish democrats most adequate. Additionally this essay will compare the ideal types to see how different the two ideologies are. The analysis and conclusion shows that the two ideologies differs from each other, but they share a few aspects. The evaluation of Sweden democrats party material does show that the party shares the fundamental value of right-wing radical populism and contains attributes from that theory, including etno-nationalism and etno-pluralism. The essays conclusion is therefore that Sweden democrats appears to be a right-wing radical populist party. That creates a question for future research, why the party identify itself as a social conservative party.
76

Lincoln, the Republican Party and The Drastic Shift From Voting Republican by Black Voters, to Calhoun Conservatism and Voting for the Democratic Party Among Black Voters: The Republican Party’s Loss of the Black Vote (1865 – 2016)

Griffin, Cameron N 01 January 2016 (has links)
The thesis of this paper is that the evolution of the black vote from Republicanism to the Democratic Party was determined by several causes, and these are the subjects of my paper. Following Lincoln’s Emancipation Proclamation and the end of the Civil War, African Americans in the United States joined the Republican Party and by and large voted for Republican candidates, both in the North and South. Following the end of Reconstruction in 1876, the pressures or renewal of social conservatism, Southern localism, and the re-emergence of so-called “Calhoun” politics, along with main spread interference with African-American voting, all combined to establish the beginnings of a transition from Republican Party affiliation to increasing membership in the Democratic Party.
77

Reliable computation of invariant dynamics for conservative discrete dynamical systems

James, Jason Desmond 25 August 2010 (has links)
Computing reliable numerical approximations of invariant sets for nonlinear systems is the core problem for computer assisted study of dynamical systems. In the case of conservative systems the problem is complicated by the fact that there is no phase space dissipation to drive orbits onto attractors. In this dissertation we discuss several contributions to the field of computer assisted study of invariant dynamics in conservative systems. / text
78

On study of deterministic conservative solvers for the nonlinear boltzmann and landau transport equations

Zhang, Chenglong 24 October 2014 (has links)
The Boltzmann Transport Equation (BTE) has been the keystone of the kinetic theory, which is at the center of Statistical Mechanics bridging the gap between the atomic structures and the continuum-like behaviors. The existence of solutions has been a great mathematical challenge and still remains elusive. As a grazing limit of the Boltzmann operator, the Fokker-Planck-Landau (FPL) operator is of primary importance for collisional plasmas. We have worked on the following three different projects regarding the most important kinetic models, the BTE and the FPL Equations. (1). A Discontinuous Galerkin Solver for Nonlinear BTE. We propose a deterministic numerical solver based on Discontinuous Galerkin (DG) methods, which has been rarely studied. As the key part, the weak form of the collision operator is approximated within subspaces of piecewise polynomials. To save the tremendous computational cost with increasing order of polynomials and number of mesh nodes, as well as to resolve loss of conservations due to domain truncations, the following combined procedures are applied. First, the collision operator is projected onto a subspace of basis polynomials up to first order. Then, at every time step, a conservation routine is employed to enforce the preservation of desired moments (mass, momentum and/or energy), with only linear complexity. The asymptotic error analysis shows the validity and guarantees the accuracy of these two procedures. We applied the property of ``shifting symmetries" in the weight matrix, which consists in finding a minimal set of basis matrices that can exactly reconstruct the complete family of collision weight matrix. This procedure, together with showing the sparsity of the weight matrix, reduces the computation and storage of the collision matrix from O(N3) down to O(N^2). (2). Spectral Gap for Linearized Boltzmann Operator. Spectral gaps provide information on the relaxation to equilibrium. This is a pioneer field currently unexplored form the computational viewpoint. This work, for the first time, provides numerical evidence on the existence of spectral gaps and corresponding approximate values. The linearized Boltzmann operator is projected onto a Discontinuous Galerkin mesh, resulting in a ``collision matrix". The original spectral gap problem is then approximated by a constrained minimization problem, with objective function the Rayleigh quotient of the "collision matrix" and with constraints the conservation laws. A conservation correction then applies. We also study the convergence of the approximate Rayleigh quotient to the real spectral gap. (3). A Conservative Scheme for Approximating Collisional Plasmas. We have developed a deterministic conservative solver for the inhomogeneous Fokker-Planck-Landau equations coupled with Poisson equations. The original problem is splitted into two subproblems: collisonless Vlasov problem and collisonal homogeneous Fokker-Planck-Landau problem. They are handled with different numerical schemes. The former is approximated using Runge-Kutta Discontinuous Galerkin (RKDG) scheme with a piecewise polynomial basis subspace covering all collision invariants; while the latter is solved by a conservative spectral method. To link the two different computing grids, a special conservation routine is also developed. All the projects are implemented with hybrid MPI and OpenMP. Numerical results and applications are provided. / text
79

Kunskap, ordning och krav : Liberalism och konservatism i Folkpartiets skolpolitik

Höglund, Alexander January 2006 (has links)
<p>This paper examines the ideological content of the compulsory school policy of the Swedish Liberal Party. The aim of the study is to investigate whether the Liberal Party does really represent a liberal policy for the compulsory school, or if it is more accurately described as conservative. The analysis is carried through by two separate critical examinations of the Liberal Party motion on school politics to the parliament and the Conservative Party motion on school politics to the parliament respectively. A comparison is then made between the ideological contents of the two documents. The specific party policies are linked to universal definitions of liberalism and conservatism with the help of an analytical tool consistent of a series of educational philosophies. Difference is made between ideologically motivated purposes and concrete policy recommendations in the motion texts.</p><p>The results of the ideological content analyses and the comparison show that the compulsory school policy of the Liberal Party can be categorized as conservative, not only vis-à-vis a universal definition of liberalism and conservatism, but also in comparison with the compulsory school policy of the Conservative Party.</p>
80

Improving the accuracy of the gradient method for determining soil carbon dioxide efflux

Sánchez-Cañete, Enrique P., Scott, Russell L., van Haren, Joost, Barron-Gafford, Greg A. 01 1900 (has links)
Soil CO2 efflux (F-soil) represents a significant source of ecosystem CO2 emissions that is rarely quantified with high-temporal-resolution data in carbon flux studies. F-soil estimates can be obtained by the low-cost gradient method (GM), but the utility of the method is hindered by uncertainties in the application of published models for the diffusion coefficient. Therefore, to address and resolve these uncertainties, we compared F-soil measured by 2 soil CO2 efflux chambers and F-soil estimated by 16 gas transport models using the GM across 1year. We used 14 published empirical gas diffusion models and 2 in situ models: (1) a gas transfer model called Chamber model obtained using a calibration between the chamber and the gradient method and (2) a diffusion model called SF6 model obtained through an interwell conservative tracer experiment. Most of the published models using the GM underestimated cumulative annual F-soil by 55% to 361%, while the Chamber model closely approximated cumulative F-soil (0.6% error). Surprisingly, the SF6 model combined with the GM underestimated F-soil by 32%. Differences between in situ models could stem from the Chamber model implicitly accounting for production of soil CO2, while the conservative tracer model does not. Therefore, we recommend using the GM only after calibration with chamber measurements to generate reliable long-term ecosystem F-soil measurements. Accurate estimates of F-soil will improve our understanding of soil respiration's contribution to ecosystem fluxes.

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