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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.
221

Äventyrsgenrens funktioner från fiktionsprosa till interaktiv fiktion : En intermedial jämförelse mellan fyra verk / The Adventure genre’s functions from fiction prose to interactive fiction : An intermedial comparison between four works

Olsson, Simon January 2016 (has links)
The purpose of this thesis is to apply the adventure formulas laid out by John G. Cawelti and the dramatis personae written by Vladimir Propp to the traditional adventure books Le Tour du monde en quatre-vingts jour (1874) and Treasure Island (1883) and the interactive fictions The Secret of Monkey Island (1990) and 80 Days (2014), both in the adventure genre. After they have been applied, I will compare Le Tour du monde en quatre-vingts jour with 80 Days and Treasure Island with The Secret of Monkey Island by how the formulas and dramatis personae work and evolve in the fictions. To start things off, I will present the four works and then go through the relevant parts of Cawelti’s formula and Propp’s dramatis personae. Thereafter, I will explain what interactive fiction might be by using Espen J. Aarseth’s Cybertext. Important concepts will be clarified as well.    The analysis in this thesis starts afterwards. Le Tour du monde en quatre-vingts jour and 80 Days will be the first two works to be analysed after Cawelti and thereafter Propp. When that is done, I will conclude what I have found. The same process will be done with Treasure Island and The Secret of Monkey Island. After that, I will make a concluding comparison between 80 Days and The Secret of Monkey Island and finally conclude whether Cawelti and Propp can be applied to interactive fiction.
222

Conservative decision-making and inference in uncertain dynamical systems

Calliess, Jan-Peter January 2014 (has links)
The demand for automated decision making, learning and inference in uncertain, risk sensitive and dynamically changing situations presents a challenge: to design computational approaches that promise to be widely deployable and flexible to adapt on the one hand, while offering reliable guarantees on safety on the other. The tension between these desiderata has created a gap that, in spite of intensive research and contributions made from a wide range of communities, remains to be filled. This represents an intriguing challenge that provided motivation for much of the work presented in this thesis. With these desiderata in mind, this thesis makes a number of contributions towards the development of algorithms for automated decision-making and inference under uncertainty. To facilitate inference over unobserved effects of actions, we develop machine learning approaches that are suitable for the construction of models over dynamical laws that provide uncertainty bounds around their predictions. As an example application for conservative decision-making, we apply our learning and inference methods to control in uncertain dynamical systems. Owing to the uncertainty bounds, we can derive performance guarantees of the resulting learning-based controllers. Furthermore, our simulations demonstrate that the resulting decision-making algorithms are effective in learning and controlling under uncertain dynamics and can outperform alternative methods. Another set of contributions is made in multi-agent decision-making which we cast in the general framework of optimisation with interaction constraints. The constraints necessitate coordination, for which we develop several methods. As a particularly challenging application domain, our exposition focusses on collision avoidance. Here we consider coordination both in discrete-time and continuous-time dynamical systems. In the continuous-time case, inference is required to ensure that decisions are made that avoid collisions with adjustably high certainty even when computation is inevitably finite. In both discrete-time and finite-time settings, we introduce conservative decision-making. That is, even with finite computation, a coordination outcome is guaranteed to satisfy collision-avoidance constraints with adjustably high confidence relative to the current uncertain model. Our methods are illustrated in simulations in the context of collision avoidance in graphs, multi-commodity flow problems, distributed stochastic model-predictive control, as well as in collision-prediction and avoidance in stochastic differential systems. Finally, we provide an example of how to combine some of our different methods into a multi-agent predictive controller that coordinates learning agents with uncertain beliefs over their dynamics. Utilising the guarantees established for our learning algorithms, the resulting mechanism can provide collision avoidance guarantees relative to the a posteriori epistemic beliefs over the agents' dynamics.
223

Predictability of a laboratory analogue for planetary atmospheres

Young, Roland Michael Brendon January 2009 (has links)
The thermally-driven rotating annulus is a laboratory experiment used to study the dynamics of planetary atmospheres under controlled and reproducible conditions. The predictability of this experiment is studied by applying the same principles used to predict the atmosphere. A forecasting system for the annulus is built using the analysis correction method for data assimilation and the breeding method for ensemble generation. The results show that a range of flow regimes with varying complexity can be accurately assimilated, predicted, and studied in this experiment. This framework is also intended to demonstrate a proof-of-concept: that the annulus could be used as a testbed for meteorological techniques under laboratory conditions. First, a regime diagram is created using numerical simulations in order to select points in parameter space to forecast, and a new chaotic flow regime is discovered within it. The two components of the framework are then used as standalone algorithms to measure predictability in the perfect model scenario and to demonstrate data assimilation. With a perfect model, regular flow regimes are found to be predictable until the end of the forecasts, and chaotic regimes are predictable over hundreds of seconds. There is a difference in the way predictability is lost between low-order chaotic regimes and high-order chaos. Analysis correction is shown to be accurate in both regular and chaotic regimes, with residual velocity errors about 3-8 times the observational error. Specific assimilation scenarios studied include information propagation from data-rich to data-poor areas, assimilation of vortex shedding observations, and assimilation over regime and rotation rate transitions. The full framework is used to predict regular and chaotic flow, verifying the forecasts against laboratory data. The steady wave forecasts perform well, and are predictable until the end of the available data. The amplitude and structural vacillation forecasts lose quality and skill by a combination of wave drift and wavenumber transition. Amplitude vacillation is predictable up to several hundred seconds ahead, and structural vacillation is predictable for a few hundred seconds.
224

Industrial Phantasmagoria : Subcultural Interactive Cinema Meets Mass-Cultural Media of Simulation

Dymek, Mikolaj January 2010 (has links)
The video game industry has in three decades gone from a garage hobby to a global multi-billion euro media industry that challenges the significantly older and established cultural industries. After decades of explosive growth the industry surprisingly finds itself in a crisis – in terms of sales, future trajectories and creative paradigms. The global gaming culture receives substantial attention from society, media and academia – but the industry itself appears in comparison as an enigmatic terra incognita with astonishingly little dedicated research. This thesis aims to amend this situation by presenting a study at the cross-section of the video game industry, game studies, literary theory, cultural industries and business studies. It deals with the following question: how does the global game industry relate to its own product, in terms of communication and media dimensions, and what are the (business) consequences, in terms of production, strategy and commercial/creative innovation, of this relationship? This study’s departure point is constituted by a comprehensive description of the industry’s structure, dynamics and processes, based on extensive interviews with industry professionals. It is followed by an examination and comparison of the game industry with other media/cultural industries in relation to their economy and business dynamics. With inconclusive answers regarding the medium-industry relation, this study proceeds by exploring literary theories from the field of game studies, in order to gain insights into the dynamics of medium and industry. Literary theories from ludology and narratology provide rewarding perspectives on this inquiry, since it is found that the ontological dichotomy of simulation vs. respresentation present in the interpretational realm of the game medium is also reflected in the industry and its dynamics. This has pivotal consequences for the analysis of the game industry. This study concludes by positing the current critical condition of the industry as an extremely decisive moment in its history: will it become a truly universal mass-medium, or will it continue down its subcultural path? Subcultural “interactive cinema” meets mass-cultural media of simulation – how will the industry evolve? / QC20100708
225

Sur quelques problèmes non-supervisés impliquant des séries temporelles hautement dèpendantes

Khaleghi, Azadeh 18 November 2013 (has links) (PDF)
Cette thèse est consacrée à l'analyse théorique de problèmes non supervisés impliquant des séries temporelles hautement dépendantes. Plus particulièrement, nous abordons les deux problèmes fondamentaux que sont le problème d'estimation des points de rupture et le partitionnement de séries temporelles. Ces problèmes sont abordés dans un cadre extrêmement général oùles données sont générées par des processus stochastiques ergodiques stationnaires. Il s'agit de l'une des hypothèses les plus faibles en statistiques, comprenant non seulement, les hypothèses de modèles et les hypothèses paramétriques habituelles dans la littérature scientifique, mais aussi des hypothèses classiques d'indépendance, de contraintes sur l'espace mémoire ou encore des hypothèses de mélange. En particulier, aucune restriction n'est faite sur la forme ou la nature des dépendances, de telles sortes que les échantillons peuvent être arbitrairement dépendants. Pour chaque problème abordé, nous proposons de nouvelles méthodes non paramétriques et nous prouvons de plus qu'elles sont, dans ce cadre, asymptotiquement consistantes. Pour l'estimation de points de rupture, la consistance asymptotique se rapporte à la capacité de l'algorithme à produire des estimations des points de rupture qui sont asymptotiquement arbitrairement proches des vrais points de rupture. D'autre part, un algorithme de partitionnement est asymptotiquement consistant si le partitionnement qu'il produit, restreint à chaque lot de séquences, coïncides, à partir d'un certain temps et de manière consistante, avec le partitionnement cible. Nous montrons que les algorithmes proposés sont implémentables efficacement, et nous accompagnons nos résultats théoriques par des évaluations expérimentales. L'analyse statistique dans le cadre stationnaire ergodique est extrêmement difficile. De manière générale, il est prouvé que les vitesses de convergence sont impossibles à obtenir. Dès lors, pour deux échantillons générés indépendamment par des processus ergodiques stationnaires, il est prouvé qu'il est impossible de distinguer le cas où les échantillons sont générés par le même processus de celui où ils sont générés par des processus différents. Ceci implique que des problèmes tels le partitionnement de séries temporelles sans la connaissance du nombre de partitions ou du nombre de points de rupture ne peut admettre de solutions consistantes. En conséquence, une tâche difficile est de découvrir les formulations du problème qui en permettent une résolution dans ce cadre général. La principale contribution de cette thèse est de démontrer (par construction) que malgré ces résultats d'impossibilités théoriques, des formulations naturelles des problèmes considérés existent et admettent des solutions consistantes dans ce cadre général. Ceci inclut la démonstration du fait que le nombre de points de rupture corrects peut être trouvé, sans recourir à des hypothèses plus fortes sur les processus stochastiques. Il en résulte que, dans cette formulation, le problème des points de rupture peut être réduit à du partitionnement de séries temporelles. Les résultats présentés dans ce travail formulent les fondations théoriques pour l'analyse des données séquentielles dans un espace d'applications bien plus large.
226

Study of compact quantum groups with probabilistic methods : caracterization of ergodic actions and quantum analogue of Noether's isomorphisms theorems / Etude des groupes quantiques compacts avec des méthodes probabilistes : caractérisation d'actions d'action ergodiques et analogues quantiques des théorèmes d'isomorphismes de Noether

Omar hoch, Souleiman 29 June 2017 (has links)
Cette thèse étudie des problèmes liés aux treillis des sous-groupes quantiques et la caractérisationdes actions ergodiques et des états idempotents d’un groupe quantique compact.Elle consiste en 3 parties. La première partie présente des résultats préliminaires sur lesgroupes quantiques localement compacts, les sous-groupes quantiques normaux ainsi queles actions ergodiques et les états idempotents. La seconde partie étudie l’analogue quantiquede la règle de modularité de Dedekind et de l’analogue quantique des théorèmesd’isomorphisme de Noether ainsi que leur conséquences comme le théorème de raffinementde Schreier, et le théorème Jordan-Hölder. Cette partie s’inspire du travail de recherche deShuzhouWang sur l’analogue quantique du troisième théorème d’isomorphisme de Noetherpour les groupes quantiques compacts ainsi que le travail récent de Kasprzak, Khosraviet Soltan sur l’analogue quantique du premier théorème d’isomorphisme de Noether pourles groupes quantiques localement compacts. Dans la troisième partie, nous caractérisonsles états idempotents du groupe quantique compact O−1(2) en s’appuyant sur la caractérisationde ses actions ergodiques plongeables. Cette troisième partie est dans la lignedes travaux fait par Franz, Skalski et Tomatsu pour les groupes quantiques compactsUq(2), SUq(2) et SOq(3). Nous classifions au préalable les actions ergodiques et les actionsergodiques plongeables du groupe quantique compact O−1(2).Les travaux présentés dans cette thèse se basent sur deux articles de l’auteur et al.Le premier s’intitule “Fundamental isomorphism theorems for quantum groups” et a étéaccepté pour publication dans Expositionae Mathematicae et le second est intitulé “Ergodicactions and idempotent states of O−1(2)” et est en cours de finalisation pour être soumis. / This thesis studies problems linked to the lattice of quantum subgroups and characterizationof ergodic actions and idempotent states of a compact quantum group. It consistsof three parts. The first part present some preliminary results about locally compactquantum groups, normal quantum subgroups, ergodic actions and idempotent states. Thesecond part studies the quantum analog of Dedekind’s modularity law, Noether’s isomorphismtheorem and their consequences as the Schreier refinement theorem and theJordan-Hölder theorem. This part completes the work of Shuzhou WANG on the quantumanalog of the third isomorphism theorem for compact quantum group and the recentwork of Kasprzak, Khosravi and Soltan on the quantum analog of the first Noether isomorphismtheorem for locally compact quantum groups. In the third part, we characterizeidempotent states of the compact quantum group O−1(2) relying on the characterizationof embeddable ergodic actions. This third part is in the sequence of the seminal works ofFranz, Skalski and Tomatsu for the compact quantum groups Uq(2), SUq(2) and SOq(3).We classify in advance the ergodic actions and embeddable ergodic actions of the compactquantum group O−1(2).This thesis is based on two papers of the author and al. The first one is entitled“Fundamental isomorphism theorems for quantum groups” which have been accepted forpublication in Expositionae Mathematicae and the second one is entitled “Ergodic actionsand idempotent states of O−1(2)” and is being finalized for submission.
227

Mathematical evolutionary epidemiology : limited epitopes, evolution of strain structures and age-specificity

Cherif, Alhaji January 2015 (has links)
We investigate the biological constraints determined by the complex relationships between ecological and immunological processes of host-pathogen interactions, with emphasis on influenza viruses in human, which are responsible for a number of pandemics in the last 150 years. We begin by discussing prolegomenous reviews of historical perspectives on the use of theoretical modelling as a complementary tool in public health and epidemiology, current biological background motivating the objective of the thesis, and derivations of mathematical models of multi-locus-allele systems for infectious diseases with co-circulating serotypes. We provide detailed analysis of the multi-locus-allele model and its age-specific extension. In particular, we establish the necessary conditions for the local asymptotic stability of the steady states and the existence of oscillatory behaviours. For the age-structured model, results on the existence of a mild solution and stability conditions are presented. Numerical studies of various strain spaces show that the dynamic features are preserved. Specifically, we demonstrate that discrete antigenic forms of pathogens can exhibit three distinct dynamic features, where antigenic variants (i) fully self-organize and co-exist with no strain structure (NSS), (ii) sort themselves into discrete strain structure (DSS) with non-overlapping or minimally overlapping clusters under the principle of competitive exclusion, or (iii) exhibit cyclical strain structure (CSS) where dominant antigenic types are cyclically replaced with sharp epidemics dominated by (1) a single strain dominance with irregular emergence and re-emergence of certain pathogenic forms, (2) ordered alternating appearance of a single antigenic type in periodic or quasi-periodic form similar to periodic travelling waves, (3) erratic appearance and disappearance of synchrony between discrete antigenic types, and (4) phase-synchronization with uncorrelated amplitudes. These analyses allow us to gain insight into the age-specific immunological profile in order to untangle the effects of strain structures as captured by the clustering behaviours, and to provide public health implications. The age-structured model can be used to investigate the effect of age-specific targeting for public health purposes.
228

Understanding interactive fictions as a continuum : reciprocity in experimental writing, hypertext fiction, and video games

Burgess, Elizabeth January 2015 (has links)
This thesis examines key examples of materially experimental writing (B.S. Johnson’s The Unfortunates, Marc Saporta’s Composition No. 1, and Julio Cortázar’s Hopscotch), hypertext fiction (Geoff Ryman’s 253, in both the online and print versions), and video games (Catherine, L.A. Noire, The Elder Scrolls IV: Oblivion, and Phantasmagoria), and asks what new critical understanding of these ‘interactive’ texts, and their broader significance, can be developed by considering the examples as part of a textual continuum. Chapter one focuses on materially experimental writing as part of the textual continuum that is discussed throughout this thesis. It examines the form, function, and reception of key texts, and unpicks emerging issues surrounding truth and realism, the idea of the ostensibly ‘infinite’ text in relation to multicursality and potentiality, and the significance of the presence of authorial instructions that explain to readers how to interact with the texts. The discussions of chapter two centre on hypertext fiction, and examine the significance of new technologies to the acts of reading and writing. This chapter addresses hypertext fiction as part of the continuum on which materially experimental writing and video games are placed, and explores reciprocal concerns of reader agency, multicursality, and the idea of the ‘naturalness’ of hypertext as a method of reading and writing. Chapter three examines video games as part of the continuum, exploring the relationship between print textuality and digital textuality. This chapter draws together the discussions of reciprocity that are ongoing throughout the thesis, examines the significance of open world gaming environments to player agency, and unpicks the idea of empowerment in players and readers. This chapter concludes with a discussion of possible cultural reasons behind what I argue is the reader’s/player’s desire for a high level of perceived agency. The significance of this thesis, then, lies in how it establishes the existence of several reciprocal concerns in these texts including multicursality/potentiality, realism and the accurate representation of truth and, in particular, player and reader agency, which allow the texts to be placed on a textual continuum. This enables cross-media discussions of the reciprocal concerns raised in the texts, which ultimately reveals the ways in which our experiences with these interactive texts are deeply connected to our anxieties about agency in a cultural context in which individualism is encouraged, but our actual individual agency is highly limited.
229

Reading the Game: Exploring Narratives in Video Games as Literary Texts

Turley, Andrew C. 12 1900 (has links)
Indiana University-Purdue University Indianapolis (IUPUI) / Video games are increasingly recognized as powerful tools for learning in classrooms. However, they are widely neglected in the field of English, particularly as objects worthy of literary study. This project argues the place of video games as objects of literary study and criticism, combining the theories of Espen Aarseth, Ian Bogost, Henry Jenkins, and James Paul Gee. The author of this study presents an approach to literary criticism of video games that he names “player-generated narratives.” Through player-generated narratives, players as readers of video games create loci for interpretative strategies that lead to both decoding and critical inspection of game narratives. This project includes a case-study of the video game Undertale taught in multiple college literature classrooms over the course of a year. Results of the study show that a video game introduced as a work of literature to a classroom increases participation, actives disengaged students, and connects literary concepts across media through multimodal learning. The project concludes with a chapter discussing applications of video games as texts in literature classrooms, including addressing the practical concerns of migrating video games into an educational setting.
230

[pt] CONTINUIDADE HOLDER PARA OS EXPOENTES DE LYAPUNOV DE COCICLOS LINEARES ALEATÓRIOS / [en] HOLDER CONTINUITY FOR LYAPUNOV EXPONENTS OF RANDOM LINEAR COCYCLES

MARCELO DURAES CAPELEIRO PINTO 27 May 2021 (has links)
[pt] Uma medida de probabilidade com suporte compacto em um grupo de matrizes determina uma sequência de matrizes aleatórias i.i.d. Considere o processo multiplicativo correspondente e suas médias geométricas. O teorema de Furstenberg-Kesten, análogo da lei dos grandes números neste cenário, garante que as médias geométricas desse processo multiplicativo convergem quase certamente para uma constante, chamada de expoente de Lyapunov maximal da medida dada. Este conceito pode ser reformulado no contexto mais geral da teoria ergódica usando cociclos lineares aleatórios sobre o shift de Bernoulli. Uma questão natural diz respeito às propriedades de regularidade do expoente de Lyapunov como uma função dos seus dados. Sob uma condição de irredutibilidade e em um cenário específico (que foi posteriormente generalizado por vários autores) Le Page estabeleceu a continuidade de Holder do expoente de Lyapunov. Recentemente, Baraviera e Duarte obtiveram uma prova direta e elegante deste tipo de resultado. Seu argumento usa a fórmula de Furstenberg e as propriedades de regularidade da medida estacionária. Seguindo sua abordagem, neste trabalho obtemos um novo resultado mostrando que, sob a mesma hipótese de irredutibilidade, o expoente de Lyapunov depende Hölder continuamente da medida, relativamente à métrica de Wasserstein, generalizando assim o resultado de Baraviera e Duarte. / [en] A compactly supported probability measure on a group of matrices determines a sequence of i.i.d. random matrices. Consider the corresponding multiplicative process and its geometric averages. Furstenberg-Kesten s theorem, the analogue of the law of large numbers in this setting, ensures that the geometric averages of this multiplicative process converge almost surely to a constant, called the maximal Lyapunov exponent of the given measure. This concept can be reformulated in the more general context of ergodic theory using random linear cocycles over the Bernoulli shift. A natural question concerns the regularity properties of the Lyapunov exponent as a function of the data. Under an irreducibility condition and in a specific setting (which was later generalized by various authors) Le Page established the Holder continuity of the Lyapunov exponent. Recently, Baraviera and Duarte obtained a direct and elegant proof of this type of result. Their argument uses Furstenberg s formula and the regularity properties of the stationary measure. Following their approach, in this work we obtain a new result showing that under the same irreducibility hypothesis, the Lyapunov exponent depends Holder continuously on the measure, relative to the Wasserstein metric, thus generalizing the result of Baraviera and Duarte.

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