960 resultados para Error in essence
Resumo:
This study examines how to institutional environment of gambling is currently in motion both in Europe and Finland. Furthermore, it examines the criticism by Finnish professional sport clubs directed towards the national gambling monopolies, especially Veikkaus Oy. This criticism addresses the acclaimed issue of low or non-existing sponsorship funds coming to the clubs despite the clubs’ duties to promote Veikkaus Oy in their stadiums etc. In essence the main research objective was to examine the interaction and institutional environments of both Finnish professional sport clubs and gambling regulation. This was done through three sub-objectives: 1) to analyze professional sport as business and its institutional environment 2) to analyze the institutions of gambling in their current state and their potential future 3) to evaluate the potential impact of an institutional change in gambling legislation to the professional sport clubs The findings from Finland were then compared to those of Denmark where an institutional change had occurred in gambling regulation. Empirical data was collected through multiple interviews. Interviewees represented sport clubs (7), sport association (1), sport league (1), Finnish monopoly representatives (2), commercial gambling providers (1), Danish monopoly system representatives (1), Danish sport club (1). In addition a vast amount of secondary data (e.g. Green and white books by EU, court decisions, a variety of studies etc.). Theoretically this study combines the aspects of institutional theory with the theory of professional sports as business. This proved to be a rather new approach and no published literature was found to have done specifically this. The findings of this study are twofold, on the European level it is clear that the momentum if towards a more liberated gambling market while Finland is at the moment trying to go the opposite direction and uphold its monopoly. From the sport club’s level the findings suggest that currently sport clubs do not directly benefit from the funds originated from Veikkaus Oy as these funds are more or less used on the association/league levels. However, the clubs themselves are also lacking in self-criticism as they are lacking in clear sponsorship packages/programs which Veikkaus Oy might be interested in participating. If liberation of the gambling market would occur it is highly possible that that the largest clubs in football and ice-hockey would be the main beneficiaries while smaller clubs and sports could possibly be worse off than currently. These interpretations were well supported by the findings from Denmark.
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This work deals with an hybrid PID+fuzzy logic controller applied to control the machine tool biaxial table motions. The non-linear model includes backlash and the axis elasticity. Two PID controllers do the primary table control. A third PID+fuzzy controller has a cross coupled structure whose function is to minimise the trajectory contour errors. Once with the three PID controllers tuned, the system is simulated with and without the third controller. The responses results are plotted and compared to analyse the effectiveness of this hybrid controller over the system. They show that the proposed methodology reduces the contour error in a proportion of 70:1.
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Yrityksen selviytyminen ja menestyminen ovat riippuvaisia sen kyvystä innovoida, luoda tietoa ja hyödyntää tietämystä ja keksintöjä (Dunk ja Kilgore 2001). Yrityksen menestyminen erityisesti korkean teknologian alalla on siten suoraan riippuvainen sen T&T:stä, johon tehdyt investoinnit tuovat merkittäviä taloudellisia etuja yritykselle uusien tuotteiden, palveluiden ja prosessien muodossa (McEvily ja Chakravarthy 1999). Teknologinen etumatka ja sen tuotteistaminen innovatiivisiksi tarjoamiksi mahdollistaa monopolististen etujen saavuttamisen yrityksen kansainvälisessä kilpailussa (Lall 1977). Tämä kaltainen kilpailuetu voidaan saavuttaa yrityksen kyvyllä yhdistää maantieteellisesti hajautettu T&T:nsä tehokkaaksi verkostoksi (Porter 1986). Boehen (2008) mukaan T&T:n globalisoitumista voidaan johtaa eri hallintömuodoilla: T&T:n kansainvälistymisellä, T&T:n ulkomaille sijoittamisella ja T&T ulkomaille ulkoistamisella. T&T:n globalisoituminen on osa 2000-luvun taloudellista muutosta, ja sille on esitetty useita vaikuttavia tekijöitä, kuten kustannuserot, työvoimaresurssit, erityisosaamiskeskukset, paikallinen teknologia osaaminen ja kohdemarkkinoiden potentiaali (bardhan 2006; Norwood, ym. 2006; von Zedtwitz ja Gassmann 2002). Tutkimuksen on osoitettu eroavan tuotekehityksestä ja eri tekijöiden on osoitettu vaikuttavan niihin (von Zedtwitz ja Gassmann 2002; Leifer ja Triscari 1987). Samoin T&T on osoitettu olevan jatkumo perustavanlaatuisesta soveltavaan ja lääkekehityksen muodostavan vastaavan T&T jatkumon (Lall 1980; Iansiti 1993), jonka yksittäiset osat vaikuttavat sen hallintomuotoon. Tutkimus esittää eri tekijöitä voivan hyödyntää hallintomuodosta riippuen. Tätä tutkimusta varten tutkija haastatteli lääketeollisuuden johtajia Kiinassa vahvistaakseen tai hylätäkseen eri tekijöitä ja niiden suhdetta lääketeollisen T&T:n hallintomuotoihin. Markkinoiden todettiin olevan ensisijainen tekijä mutta myös kustannuserojen, insentiivien, työvoimaresurssien ja erityisosaamiskeskusten merkitys T&T:n globalisoitumiseen vaikuttavina tekijöinä vahvistettiin yhdessä perusvaatimusten ja riskitekijöiden kanssa. Tutkimuksessa vahvistetaan myös lääketeollisen T&T-jatkumon vaikutus ja esitetään viitekehys hallintomuodoille.
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Firm's survival and success, which are dependent on its ability to innovate, to create knowledge and to capitalize on inventions and know-how, is in essence directly linked to its R&D process (Dunk and Kilgore 2001). Especially in technology driven industries, such as the pharmaceuticals, there are significant positive returns to R&D investments through introduction of new or improved products and services (McEvily and Chakravarthy 1999). Technological lead and its transformation to innovative products as fruits of corporate R&D can be seen as monopolistic advantage that helps enterprises to compete in today’s market (Lall 1977). This competitive advantage can be derived from corporation's ability to integrate its activities across geographic locations (Porter 1986). According to Boehe (2008) globalization of R&D can executed with different governance forms: R&D internationalization, R&D offshoring or R&D offshore outsourcing. Globalization of R&D is intervened with the changes in global economy of the 21st century. Some studies argue for its influencing factors to be access to vast skilled labor pools and centers of excellence (Bardhan 2006). Other studies indicate the R&D cost differentials between countries to be the major expected benefit (Norwood et al. 2006). Von Zedtwitz and Gassmann (2002) presented benefits as divided to accessing markets and customers or to accessing local science and technology. This study proposes that based on governance form distinct factor derived benefits can be capitalized. To corroborate or refute factors and their relations on R&D globalization governance forms, an empirical study based on expert interviews of pharmaceutical directors was conducted in the People's Republic of China. The market was found to be the major influencing factor. Local requirements and adaptation were corroborated as factors connected with markets. Furthermore, influencing factors, such as labour, centers of excellence, cost, financial incentives were corroborated together with conditional and risk factors. Furthermore this research argues that the globalization of pharmaceutical R&D is dependent on the financial, scientific and operational requirements of the drug discovery stage. And thus establishes the influence of drug discovery's stages continuum on pharmaceutical R&D globalization. Finally, a R&D globalization governance form decision framework is proposed based on the frameworks presented in literature and author's corroborated empirical findings.
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This thesis takes seriously the proposition that existentialism is a lived philosophy. While Descartes' proof for the existence of God initially sparked my interest in philosophy, the insights of existentialism have allowed me to appropriate philosophy as a way of life. I apply the insights of Kierkegaard's writings to my spiritual and philosophy development. Philosophy is personal, and Kierkegaard's writings deal with the development of the person in his aesthetic, ethical and religious dimensions. Philosophy is a struggle, and this thesis, reveals the existential struggle of the individual in despair. The thesis argues that authentic faith actually entails faith. The existential believer has this faith whereas the religious believer does not. The subjectively reflective existential believer recognizes that a leap of faith is needed; anything else, is just historical, speculative knowledge. The existential believer or, the Knight of Faith, realizes that a leap of faith is needed to become open in inwardness to receive the condition to understand the paradoxes that faith presents. I will present Kierkegaard's "Analogy of a House" which is in essence, the backbone of his philosophy. I will discuss the challenge of moving from one floor to the next. More specifically, I will discuss the anxiety that is felt in the very moment of the transition from the first floor to the second floor. I will outline eight paradoxes that must me resolved in order for the individual to continue on his journey to the top floor of the house. I will argue that Kierkegaard's example of Abraham as a Knight of Faith is incorrect, that Abraham was in fact not a Knight of Faith. I will also argue that we should find our own exemplars in our own lives by looking for Knight of Faith traits in people we know and then trying to emulate those people. I will also discuss Unamuno's "paradoxical faith" and argue that this kind of faith is a strong alternative to those who find that Kierkegaard's existential faith is not a possibility.
Resumo:
The NeO'liberal State and the Crisis ofPublic Service Broadcasting in the Anglo-American Democracies The purpose ofthis analysis ofthe present condition ofpublic service broadcasting in the Anglo- American democracies was to investigate whether such media can still be regarded as the primarypublic spherefor a dialogue between each nation 's civil society and the State. The motivationfor this thesis was based on a presumption that such fora for public discussion on the central issues of each society have become viewed as less relevant bypoliticians andpolicy-makers and thepublics they were intended to serve in the Anglo-American democracies over thepast two decades. It is speculated that this is the case because ofa beliefthat the post-war consensus between the respective States andpublics that led to the construction of the Keynesian Welfare State and the notion ofpublic service broadcasting has been displaced by an individualistic, neo-liberal, laissez-faire ideology. In other words, broadcasting as a consumer-oriented, commercial commodity has superseded concerns pertaining to the importance ofthe public interest. The methodology employed in this thesis is a comparative analysisfrom a criticalpolitical economy perspective. It was considered appropriate to focus on the United Kingdom, Australia, Canada and the\ United States because they comprise the four largest Anglo-American nations with democratic political systems andprimarily market economies. Justificationfor this particular sample is reinforced by thefact that case study countries also share a common socio-political and economic tradition. The evidence assembledfor this thesis consisted almost exclusively ofexisting literature on the subjects ofpublic service broadcasting, global economic andpolitical integration, and the ascendance ofthe 'free-market ' ethos in Western democracies since the late mid- to late-1970s. In essence, this thesis could be considered as a reinterpretation ofthe existing literature relevant to these issues. Several important common features werefound among the political, economic and broadcasting systems of the four case study nations. It is proposed that the prevalence of the neo-liberal world view throughout the political and policy environments of the four countries has undermined the stability and credibility of each nation 's national public service broadcasting organization, although with varying intensity and effect,. Deregulation ofeach nation 's broadcasting system and the supremacy ofthe notion of 'consumer sovereignty' have marginalized the view of broadcasting on any basis other than strictly economic criteria in thefour case study countries. This thesis concludes that,for a reconstruction ofa trulyparticipatory anddemocraticpublicsphere to be realized in the present as well as thefuture, a reassessment ofthe conventional concept ofthe 'public sphere ' is necessary. Therefore, it is recommended that thefocus ofpolicy-makers in each Anglo-American democracy be redirectedfrom that which conceived ofan all-encompassing, large, state-ownedand operated public broadcasting service toward a view which considers alternativeforms ofpublic communication, such as local community and ethnic broadcasting operations, that are likely to be more responsive to the needs of the increasingly diverse and heterogeneous populations that comprise the modem Anglo-American democracies. The traditional conception of public broadcasters must change in accordance with its contemporary environment if the fundamental principles of the public sphere and public service broadcasting are to be realized.
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The influence of peak-dose drug-induced dyskinesia (DID) on manual tracking (MT) was examined in 10 dyskinetic patients (OPO), and compared to 10 age/gendermatched non-dyskinetic patients (NDPD) and 10 healthy controls. Whole body movement (WBM) and MT were recorded with a 6-degrees of freedom magnetic motion tracker and forearm rotation sensors, respectively. Subjects were asked to match the length of a computer-generated line with a line controlled via wrist rotation. Results show that OPO patients had greater WBM displacement and velocity than other groups. All groups displayed increased WBM from rest to MT, but only DPD and NDPO patients demonstrated a significant increase in WBM displacement and velocity. In addition, OPO patients exhibited excessive increase in WBM suggesting overflow DID. When two distinct target pace segments were examined (FAST/SLOW), all groups had slight increases in WBM displacement and velocity from SLOW to FAST, but only OPO patients showed significantly increased WBM displacement and velocity from SLOW to FAST. Therefore, it can be suggested that overflow DID was further increased with increased task speed. OPO patients also showed significantly greater ERROR matching target velocity, but no significant difference in ERROR in displacement, indicating that significantly greater WBM displacement in the OPO group did not have a direct influence on tracking performance. Individual target and performance traces demonstrated this relatively good tracking performance with the exception of distinct deviations from the target trace that occurred suddenly, followed by quick returns to the target coherent in time with increased performance velocity. In addition, performance hand velocity was not correlated with WBM velocity in DPO patients, suggesting that increased ERROR in velocity was not a direct result of WBM velocity. In conclusion, we propose that over-excitation of motor cortical areas, reported to be present in DPO patients, resulted in overflow DID during voluntary movement. Furthermore, we propose that the increased ERROR in velocity was the result of hypermetric voluntary movements also originating from the over-excitation of motor cortical areas.
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This thesis deals with the nature of ignorance as it was interpreted in the Upani~adic tradition, specifically in Advaita Vedanta, and in early and Mahayana Buddhism , e specially in the Madhyamika school of Buddhism. The approach i s a historical and comparative one. It examines the early thoughts of both the upanis.a ds and Buddhism abou t avidya (ignorance), shows how the notion was treated by the more speculative and philosphically oriented schools which base d themselves on the e arly works, and sees how their views differ. The thesis will show that the Vedinta tended to treat avidya as a topic for metaphysical s peculation as t he s chool developed, drifting from its initial e xistential concerns, while the Madhyamika remained in contact with the e xistential concerns evident in the first discourses of the Buddha. The word "notion" has been chosen for use in referring t o avidya, even though it may have non-intellectual and emotional connotations, to avoid more popular a lternatives such as "concept" or "idea". In neither the Upani,ads, Advaita Vedanta, or Buddhism is ignorance merely a concept or an idea. Only in a secondary sense, in texts and speech , does it become one. Avidya has more to do with the lived situation in which man finds himself, with the subjectobject separation in which he f eels he exists, than with i i i intel lect ual constr ucts . Western thought has begun to r ealize the same with concerns such as being in modern ontology, and has chosen to speak about i t i n terms of the question of being . Avidya, however, i s not a 'question' . If q ue stions we r e to be put regarding the nature of a vidya , they would be more of t he sort "What is not avidya?", though e ven here l anguage bestows a status t o i t which avidya does not have. In considering a work of the Eastern tradition, we f ace t he danger of imposing Western concepts on it. Granted t hat avidya is customari ly r endered i n English as ignorance, the ways i n which the East and West view i gno rance di f f er. Pedagogically , the European cultures, grounded in the ancient Greek culture, view ignorance as a l ack or an emptiness. A child is i gnorant o f certain t hings and the purpose o f f ormal education , in f act if not in theory, is to fill him with enough knowledge so that he can cope wit h t he complexities and the e xpectations of s ociety. On another level, we feel t hat study and research will l ead t o the discovery o f solutions, which we now lack , for problems now defying solut i on . The East, on the o t her hand, sees avidya in a d i fferent light.Ignorance isn't a lack, but a presence. Religious and philosophical l iterature directs its efforts not towards acquiring something new, but at removing t.he ideas and opinions that individuals have formed about themselves and the world. When that is fully accomplished, say the sages , t hen Wisdom, which has been obscured by those opinions, will present itself. Nothing new has to be learned, t hough we do have t o 'learn' that much. The growing interest in t he West with Eastern religions and philosophies may, in time, influence our theoretical and practical approaches to education and learning, not only in the established educati onal institutions, but in religious , p sychological, and spiritual activities as well. However, the requirements o f this thesis do no t permit a formulation of revolutionary method or a call to action. It focuses instead on the textual arguments which attempt to convince readers that t he world in which they take themselves to exist is not, in essence, real, on the ways i n which the l imitations of language are disclosed, and on the provisional and limited schemes that are built up to help students see through their ignorance. The metaphysic s are provisional because they act only as spurs and guides. Both the Upanisadic and Buddhist traditions that will be dealt with here stress that language constantly fails to encompass the Real. So even terms s uch as 'the Real', 'Absolute', etc., serve only to lead to a transcendent experience . The sections dealing with the Upanisads and Advaita Vedanta show some of the historical evolution of the notion of avidya, how it was dealt with as maya , and the q uestions that arose as t o its locus. With Gau?apada we see the beginnings of a more abstract treatment of the topic, and , the influence of Buddhism. Though Sankhara' S interest was primarily directed towards constructing a philosophy to help others attain mok~a ( l iberation), he too introduced t echnica l t e rminology not found in the works of his predecessors. His work is impressive , but areas of it are incomplete. Numbers of his followers tried to complete the systematic presentation of his insi ghts . Their work focuses on expl anat i ons of adhyasa (superimposition ) , t he locus and object of ignorance , and the means by which Brahman takes itself to be the jiva and the world. The section on early Buddhism examines avidya in the context o f the four truths, together with dubkha (suffering), the r ole it p l ays in t he chain of dependent c ausation , a nd t he p r oblems that arise with t he doctrine of anatman. With t he doct rines of e arly Buddhism as a base, the Madhyamika elaborated questions that the Buddha had said t e nded not t o edi f ication. One of these had to do with own - being or svabhava. Thi s serves a s a centr e around which a discussion o f i gnorance unfolds, both i ndividual and coll ective ignorance. There follows a treatment of the cessation of ignorance as it is discussed within this school . The final secti on tries to present t he similarities and differences i n the natures o f ignorance i n t he two traditions and discusses the factors responsible for t hem . ACKNOWLEDGEMENTS I would like to thank Dr. Sinha for the time spent II and suggestions made on the section dealing with Sankara and the Advait.a Vedanta oommentators, and Dr. Sprung, who supervised, direoted, corrected and encouraged the thesis as a whole, but especially the section on Madhyamika, and the final comparison.
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The exact mechanistic understanding of various organocatalytic systems in asymmetric reactions such as Henry and aza-Henry transformations is important for developing and designing new synthetic organocatalysts. The focus of this dissertation will be on the use of density functional theory (DFT) for studying the asymmetric aza-Henry reaction. The first part of the thesis is a detailed mechanistic investigation of a poorly understood chiral bis(amidine) (BAM) Brønsted acid catalyzed aza-Henry reaction between nitromethane and N-Boc phenylaldimine. The catalyst, in addition to acting as a Brønsted base, serves to simultaneously activate both the electrophile and the nucleophile through dual H-bonding during C-C bond formation and is thus essential for both reaction rate and selectivity. Analysis of the H-bonding interactions revealed that there was a strong preference for the formation of a homonuclear positive charge-assisted H-bond, which in turn governed the relative orientation of substrate binding. Attracted by this well-defined mechanistic investigation, the other important aspect of my PhD research addressed a detailed theoretical analysis accounting for the observed selectivity in diastereoselective versions of this reaction. A detailed inspection of the stereodetermining C-C bond forming transition states for monoalkylated nitronate addition to a range of electronically different aldimines, revealed that the origins of stereoselectivity were controlled by a delicate balance of different factors such as steric, orbital interactions, and the extent of distortion in the catalyst and substrates. The structural analysis of different substituted transition states established an interesting dependency on matching the shape and size of the catalyst (host molecule) and substrates (guest molecules) upon binding, both being key factors governing selectivity, in essence, offering an analogy to positive cooperative binding effect of catalytic enzymes and substrates in Nature. In addition, both intra-molecular (intra-host) and inter-molecular (host-guest, guest-guest) stabilizing interactions play a key role to the high π-facial selectivity. The application of dispersion-corrected functionals (i.e., ωB97X-D and B3LYP-D3) was essential for accurately modeling these stabilizing interactions, indicating the importance of dispersion effects in enantioselectivity. As a brief prelude to more extensive future studies, the influence of a triflate counterion on both reactivity and selectivity in this reaction was also addressed.
Resumo:
Les avancés dans le domaine de l’intelligence artificielle, permettent à des systèmes informatiques de résoudre des tâches de plus en plus complexes liées par exemple à la vision, à la compréhension de signaux sonores ou au traitement de la langue. Parmi les modèles existants, on retrouve les Réseaux de Neurones Artificiels (RNA), dont la popularité a fait un grand bond en avant avec la découverte de Hinton et al. [22], soit l’utilisation de Machines de Boltzmann Restreintes (RBM) pour un pré-entraînement non-supervisé couche après couche, facilitant grandement l’entraînement supervisé du réseau à plusieurs couches cachées (DBN), entraînement qui s’avérait jusqu’alors très difficile à réussir. Depuis cette découverte, des chercheurs ont étudié l’efficacité de nouvelles stratégies de pré-entraînement, telles que l’empilement d’auto-encodeurs traditionnels(SAE) [5, 38], et l’empilement d’auto-encodeur débruiteur (SDAE) [44]. C’est dans ce contexte qu’a débuté la présente étude. Après un bref passage en revue des notions de base du domaine de l’apprentissage machine et des méthodes de pré-entraînement employées jusqu’à présent avec les modules RBM, AE et DAE, nous avons approfondi notre compréhension du pré-entraînement de type SDAE, exploré ses différentes propriétés et étudié des variantes de SDAE comme stratégie d’initialisation d’architecture profonde. Nous avons ainsi pu, entre autres choses, mettre en lumière l’influence du niveau de bruit, du nombre de couches et du nombre d’unités cachées sur l’erreur de généralisation du SDAE. Nous avons constaté une amélioration de la performance sur la tâche supervisée avec l’utilisation des bruits poivre et sel (PS) et gaussien (GS), bruits s’avérant mieux justifiés que celui utilisé jusqu’à présent, soit le masque à zéro (MN). De plus, nous avons démontré que la performance profitait d’une emphase imposée sur la reconstruction des données corrompues durant l’entraînement des différents DAE. Nos travaux ont aussi permis de révéler que le DAE était en mesure d’apprendre, sur des images naturelles, des filtres semblables à ceux retrouvés dans les cellules V1 du cortex visuel, soit des filtres détecteurs de bordures. Nous aurons par ailleurs pu montrer que les représentations apprises du SDAE, composées des caractéristiques ainsi extraites, s’avéraient fort utiles à l’apprentissage d’une machine à vecteurs de support (SVM) linéaire ou à noyau gaussien, améliorant grandement sa performance de généralisation. Aussi, nous aurons observé que similairement au DBN, et contrairement au SAE, le SDAE possédait une bonne capacité en tant que modèle générateur. Nous avons également ouvert la porte à de nouvelles stratégies de pré-entraînement et découvert le potentiel de l’une d’entre elles, soit l’empilement d’auto-encodeurs rebruiteurs (SRAE).
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Ma thèse de doctorat, intitulée Inventing Interventions: Strategies of Reappropriation in Native and First Nations Literatures traite du sujet de la réappropriation de la langue anglaise et de la langue française dans les littératures autochtones du Canada et des États-Unis, en tant que stratégie d’intervention de re-narration et de récupération. De fait, mon projet fait abstraction, autant que possible, des frontières nationales et linguistiques, vu que celles-ci sont essentiellement des constructions culturelles et coloniales. Ainsi, l’acte de réappropriation de la langue coloniale implique non seulement la maîtrise de base de cette dernière à des fins de communication, cela devient un moyen envers une fin : au lieu d’être possédés par la langue, les auteurs sur lesquels je me penche ici possèdent à présent cette dernière, et n’y sont plus soumis. Les tensions qui résultent d’un tel processus sont le produit d’une transition violente imposée et expérimentale d’une réalité culturelle à une autre, qui, pour plusieurs, n’a pas réussie et s’est, au contraire, effritée sur elle-même. Je soutiens donc que les auteurs autochtones ont créé un moyen à travers l’expression artistique et politique de répondre (dans le sens de « write back ») à l’oppression et l’injustice. À travers l’analyse d’oeuvres contemporaines écrites en anglais ou en français, que ce soit de la fiction, de l’autobiographie, de la poésie, du théâtre, de l’histoire ou du politique, ma recherche se structure autour de quatre concepts spécifiques : la langue, la résistance, la mémoire, et le lieu. J’examine comment ces concepts sont mis en voix, et comment ils sont interdépendants et s’affectent à l’intérieur du discours particulier issu des littératures autochtones et des différentes stratégies d’intervention (telles la redéfinition ou l’invention) et du mélange de différentes formules littéraires.
Inference for nonparametric high-frequency estimators with an application to time variation in betas
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We consider the problem of conducting inference on nonparametric high-frequency estimators without knowing their asymptotic variances. We prove that a multivariate subsampling method achieves this goal under general conditions that were not previously available in the literature. We suggest a procedure for a data-driven choice of the bandwidth parameters. Our simulation study indicates that the subsampling method is much more robust than the plug-in method based on the asymptotic expression for the variance. Importantly, the subsampling method reliably estimates the variability of the Two Scale estimator even when its parameters are chosen to minimize the finite sample Mean Squared Error; in contrast, the plugin estimator substantially underestimates the sampling uncertainty. By construction, the subsampling method delivers estimates of the variance-covariance matrices that are always positive semi-definite. We use the subsampling method to study the dynamics of financial betas of six stocks on the NYSE. We document significant variation in betas within year 2006, and find that tick data captures more variation in betas than the data sampled at moderate frequencies such as every five or twenty minutes. To capture this variation we estimate a simple dynamic model for betas. The variance estimation is also important for the correction of the errors-in-variables bias in such models. We find that the bias corrections are substantial, and that betas are more persistent than the naive estimators would lead one to believe.
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It has become clear over the last few years that many deterministic dynamical systems described by simple but nonlinear equations with only a few variables can behave in an irregular or random fashion. This phenomenon, commonly called deterministic chaos, is essentially due to the fact that we cannot deal with infinitely precise numbers. In these systems trajectories emerging from nearby initial conditions diverge exponentially as time evolves)and therefore)any small error in the initial measurement spreads with time considerably, leading to unpredictable and chaotic behaviour The thesis work is mainly centered on the asymptotic behaviour of nonlinear and nonintegrable dissipative dynamical systems. It is found that completely deterministic nonlinear differential equations describing such systems can exhibit random or chaotic behaviour. Theoretical studies on this chaotic behaviour can enhance our understanding of various phenomena such as turbulence, nonlinear electronic circuits, erratic behaviour of heart and brain, fundamental molecular reactions involving DNA, meteorological phenomena, fluctuations in the cost of materials and so on. Chaos is studied mainly under two different approaches - the nature of the onset of chaos and the statistical description of the chaotic state.
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Die vorliegende Arbeit befasst sich mit den Fehlern, die bei der Berechnung von Tragstrukturen auftreten können, dem Diskretisierungs- und dem Modellfehler. Ein zentrales Werkzeug für die Betrachtung des lokalen Fehlers in einer FE-Berechnung sind die Greenschen Funktionen, die auch in anderen Bereichen der Statik, wie man zeigen kann, eine tragende Rolle spielen. Um den richtigen Einsatz der Greenschen Funktion mit der FE-Technik sicherzustellen, werden deren Eigenschaften und die konsistente Generierung aufgezeigt. Mit dem vorgestellten Verfahren, der Lagrange-Methode, wird es möglich auch für nichtlineare Probleme eine Greensche Funktion zu ermitteln. Eine logische Konsequenz aus diesen Betrachtungen ist die Verbesserung der Einflussfunktion durch Verwendung von Grundlösungen. Die Greensche Funktion wird dabei in die Grundlösung und einen regulären Anteil, welcher mittels FE-Technik bestimmt wird, aufgespalten. Mit dieser Methode, hier angewandt auf die Kirchhoff-Platte, erhält man deutlich genauere Ergebnisse als mit der FE-Methode bei einem vergleichbaren Rechenaufwand, wie die numerischen Untersuchungen zeigen. Die Lagrange-Methode bietet einen generellen Zugang zur zweiten Fehlerart, dem Modellfehler, und kann für lineare und nichtlineare Probleme angewandt werden. Auch hierbei übernimmt die Greensche Funktion wieder eine tragende Rolle, um die Auswirkungen von Parameteränderungen auf ausgewählte Zielgrößen betrachten zu können.
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Building robust recognition systems requires a careful understanding of the effects of error in sensed features. Error in these image features results in a region of uncertainty in the possible image location of each additional model feature. We present an accurate, analytic approximation for this uncertainty region when model poses are based on matching three image and model points, for both Gaussian and bounded error in the detection of image points, and for both scaled-orthographic and perspective projection models. This result applies to objects that are fully three- dimensional, where past results considered only two-dimensional objects. Further, we introduce a linear programming algorithm to compute the uncertainty region when poses are based on any number of initial matches. Finally, we use these results to extend, from two-dimensional to three- dimensional objects, robust implementations of alignmentt interpretation- tree search, and ransformation clustering.