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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.
21

La nouvelle physique dans le système des mésons B

Hamel, Philippe January 2006 (has links)
Mémoire numérisé par la Direction des bibliothèques de l'Université de Montréal.
22

Cultural Collectivism and Tightness Moderate Responses to Norm Violators: Effects on Power Perception, Moral Emotions, and Leader Support

Stamkou, Eftychia, van Kleef, Gerben A., Homan, Astrid C., Gelfand, Michele J., van de Vijver, Fons J.R., van Egmond, Marieke C., Boer, Diana, Phiri, Natasha, Ayub, Nailah, Kinias, Zoe, Cantarero, Katarzyna, Treister, Dorit Efrat, Figueiredo, Ana, Hashimoto, Hirofumi, Hofmann, Eva, Lima, Renata P., Lee, I-Ching January 2019 (has links) (PDF)
Responses to norm violators are poorly understood. On one hand, norm violators are perceived as powerful, which may help them to get ahead. On the other hand, norm violators evoke moral outrage, which may frustrate their upward social mobility. We addressed this paradox by considering the role of culture. Collectivistic cultures value group harmony and tight cultures value social order. We therefore hypothesized that collectivism and tightness moderate reactions to norm violators. We presented 2,369 participants in 19 countries with a norm violation or a norm adherence scenario. In individualistic cultures, norm violators were considered more powerful than norm abiders and evoked less moral outrage, whereas in collectivistic cultures, norm violators were considered less powerful and evoked more moral outrage. Moreover, respondents in tighter cultures expressed a stronger preference for norm followers as leaders. Cultural values thus influence responses to norm violators, which may have downstream consequences for violators' hierarchical positions.
23

Effects of fermionic singlet neutrinos on high- and low-energy observables / Effets des neutrinos singulets fermioniques sur les observables de haute et basse énergie

Weiland, Cedric 04 July 2013 (has links)
Dans cette thèse, nous étudions à la fois des observables de basse et de haute énergie liée à la présence de neutrinos massifs. Les oscillations de neutrinos ont apporté des preuves indiscutables en faveur de l'existence de masses non-nulles et de mélanges. Néanmoins, la formulation originale du Modèle Standard ne permet pas d'expliquer ces observations, d'où la nécessité d'introduire de nouveaux modèles. Parmi de nombreuses possibilités, nous nous concentrons ici sur le seesaw inverse, un mécanisme générant des neutrinos massifs par l'ajout de fermions singulets de jauge au Modèle Standard. Ce modèle offre une alternative attractive aux réalisations habituelles du seesaw puisqu'il a des couplages de Yukawa potentiellement naturels (O(1)) tout en conservant l'échelle de la nouvelle physique à des énergies accessibles au LHC. Parmi de nombreux effets, ce scénario peut générer de larges écarts à l'universalité leptonique. Nous avons étudié ces signatures et trouvé que les rapports R_K et R_π constituent de nouvelles contraintes pour le seesaw inverse. Nous nous sommes aussi intéressé à l'intégration de l'inverse seesaw dans différents modèles supersymétriques. Ceci conduit à une augmentation de la section efficace de divers processus violant la saveur leptonique du fait de contributions plus importantes venant des diagrammes pingouins comportant un boson de Higgs ou Z. Finalement, nous avons aussi trouvé que les nouveaux canaux de désintégration ouverts par la présence de neutrinos stériles dans les modèles de seesaw inverse supersymétriques peuvent significativement relaxer les contraintes sur la masse et les couplages d'un boson de Higgs CP-impair. / In this doctoral thesis, we study both low- and high-energy observables related to massive neutrinos. Neutrino oscillations have provided indisputable evidence in favour of non-zero neutrino masses and mixings. However, the original formulation of the Standard Model cannot account for these observations, which calls for the introduction of new Physics. Among many possibilities, we focus here on the inverse seesaw, a neutrino mass generation mechanism in which the Standard Model is extended with fermionic gauge singlets. This model offers an attractive alternative to the usual seesaw realisations since it can potentially have natural Yukawa couplings (O(1)) while keeping the new Physics scale at energies within reach of the LHC. Among the many possible effects, this scenario can lead to deviations from lepton flavour universality. We have investigated these signatures and found that the ratios R_K and R_π provide new, additional constraints on the inverse seesaw. We have also considered the embedding of the inverse seesaw in supersymmetric models. This leads to increased rates for various lepton flavour violating processes, due to enhanced contributions from penguin diagrams mediated by the Higgs and Z bosons. Finally, we also found that the new invisible decay channels associated with the sterile neutrinos present in the supersymmetric inverse seesaw could significantly weaken the constraints on the mass and couplings of a light CP-odd Higgs boson.
24

Measurement of the CP violating phase ϕs using B⁰/s → ψ(2S)ϕ decays at the LHCb Experiment

Ferguson, Dianne January 2016 (has links)
The LHCb experiment at the Large Hadron Collider (LHC) at CERN is designed to make precise measurements of processes including B and D mesons to test the Standard Model (SM) predictions for CP violation, and to search for new physics. From its inception one of the key aims of the LHCb collaboration has been to precisely measure the CP violating phase ϕs, the weak phase due to the interference between B⁰/s -B¯⁰/s mixing and decay. Having collected 3 fb-1 of data in Run 1, the combined results of LHCb measurements of ϕs from various decay modes are in agreement with SM predictions. The aim now is to improve the precision of the LHCb measurement to be sensitive to any small deviation from the SM prediction of ϕs. One strategy to achieve this, in addition to collecting more data, is to expand the number of modes used to measure ϕs to improve the sensitivity of the combination. This thesis presents the measurement of the CP violating phase ϕs in the yet unstudied B⁰/s→ ψ(2S)ϕ decay mode. In addition to providing a measurement of ϕs the study of this mode presents an opportunity to confirm the lifetime difference of the B⁰/s mass eigenstates ∆Γs, currently only measured in the B⁰/s→ Jψϕ decay mode. The results from 3 fb-1 of LHCb data are; ϕs = 0:23+0:29-0:28 ± 0:02 rad, ∆Γs = 0:066+0:041-0:044 ± 0:007 ps-1. which are in agreement with the SM and the results from the LHCb measurement from B⁰/s→ Jψϕ decays.
25

The faithful infidel : exploring conformity and deviance of category members

Syakhroza, Maima Aulia January 2018 (has links)
This dissertation explores the drivers of why organizations, as members of its market category, choose to conform or deviate from the category’s codes. In essence, codes are the social rules category members are expected to abide by and that underpin the very existence of a category. Given the importance of producer conformity in upholding a category’s continued existence, code deviance then seems a counterintuitive strategy to pursue. Nonetheless, organizations are known to defy codes in certain instances, sometimes even pairing the violation simultaneously with conformity to other codes. On top of this, organizations also seem to be able to strategically decide which codes they will abide by to a certain extent. Each of the three papers in this dissertation investigates why organizations may choose to either conform or deviate by, respectively, examining (1) the identity difference between the code violator with the potential adopter of the code violation, (2) the taken-for-grantedness of the category the organization is a part of, and (3) the individual status and organizational identity (insider-outsider) of the producer. The main overarching finding of this dissertation is that organizations will take into account both its internal resources and external socio-environment to decide which strategy it will deploy and whether it can afford to do so. All in all, this dissertation specifies how the three factors mentioned may affect an organization’s propensity to conform or violate to category codes.
26

Desconstrução dimensional e violação de sabor / Dimensional desconstruction and flavor violation

Sá, Nayara Fonseca de 08 September 2011 (has links)
O Modelo Padrão das partículas elementares descreve com sucesso as interações eletrofracas e fortes, mostrando-se consistente com os dados experimentais disponíveis. Entretanto, há diversas questões que não são respondidas pelo mesmo, entre elas, o problema da hierarquia de gauge e o problema associado à origem das massas dos férmions. Ambos podem ser solucionados de forma natural em teorias com uma dimensão extra curva. No entanto, essas teorias violam sabor em primeira ordem de teoria de perturbações e são não renormalizáveis. Nesta dissertação utilizamos técnicas de desconstrução dimensional para resolver os problemas da hierarquia de gauge e da hierarquia de massas dos férmions com mínima violação de sabor em um modelo puramente quadridimensional. / The Standard Model of elementary particles describes the electroweak and strong interactions, and its predictions have successfully matched existing experimental data. However, there are some issues that are not addressed by this model, such as the gauge hierarchy problem and the origin of fermion masses. Both problems can be solved naturally using Warped Extra Dimensions. On the other hand, these theories are flavor-violating in tree level and are non-renormalizable. In this dissertation we apply dimensional deconstruction techniques to solve the gauge hierarchy problem and the fermion masses hierarchy problem achieving minimal flavor violation in a purely four-dimensional model
27

Determination of CKM phases through rigid polygons of flavor SU(3) amplitudes /

Dighe, Amol Shreerang. January 1997 (has links)
Thesis (Ph. D.)--University of Chicago, Dept. of Physics, August 1997. / Includes bibliographical references. Also available on the Internet.
28

A System for Detecting, Preventing and Exposing Atomicity Violations in Multithreaded Programs

Chew, Lee 13 January 2010 (has links)
Multi-core machines have become common and have led to an increase in multithreaded software. In turn, the number of concurrency bugs has also increased. Such bugs are elusive and remain difficult to solve, despite existing research. Thus, this thesis proposes a system which detects, prevents and optionally helps expose concurrency bugs. Specifically, we focus on bugs caused by atomicity violations, which occur when thread interleaving violates the programmer’s assumption that a code section executes atomically. At compile-time, our system performs static analysis to identify code sections where violations could occur. At run-time, we use debug registers to monitor these sections for interleaving thread accesses which would cause a violation. If detected, we undo their effects and thus prevent the violation. Optionally, we help expose atomicity violations by perturbing thread scheduling during execution. Our results demonstrate that the system is effective and imposes low overhead.
29

The Neural Correlates of Implicit Theory Violation

Xu, Xiaowen 04 January 2012 (has links)
Implicit theories play an important role in the structure and maintenance of people’s sense of meaning, and violations to one’s theory can create significant distress. Using electroencephalography (EEG), this study examined the neural correlates of implicit theory violation. Participants were primed with one of two implicit theories of success attainment and were then shown a series of words that either confirmed or violated that theory. Analyses revealed that compared to implicit theory confirmations, implicit theory violations produced greater N400 amplitudes, which is a brain wave associated with “semantic violations,” or violations of meaning. Current literature on the N400 has been limited to language-specific semantic violations. Therefore, these results represent a novel extension of the N400 to include violations of complex lay theories of human behavior. Furthermore, these data suggest that implicit theories represent a fundamental type of semantic knowledge that helps perceivers to generate predictions about the social world.
30

A System for Detecting, Preventing and Exposing Atomicity Violations in Multithreaded Programs

Chew, Lee 13 January 2010 (has links)
Multi-core machines have become common and have led to an increase in multithreaded software. In turn, the number of concurrency bugs has also increased. Such bugs are elusive and remain difficult to solve, despite existing research. Thus, this thesis proposes a system which detects, prevents and optionally helps expose concurrency bugs. Specifically, we focus on bugs caused by atomicity violations, which occur when thread interleaving violates the programmer’s assumption that a code section executes atomically. At compile-time, our system performs static analysis to identify code sections where violations could occur. At run-time, we use debug registers to monitor these sections for interleaving thread accesses which would cause a violation. If detected, we undo their effects and thus prevent the violation. Optionally, we help expose atomicity violations by perturbing thread scheduling during execution. Our results demonstrate that the system is effective and imposes low overhead.

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