A search for resonance signals from new physics models was performed using the ATLAS dijet invariant mass spectrum at a center-of-mass energy of 8 TeV. The full dataset from the 2012 data-taking period was used, corresponding to an integrated luminosity of 20.3 fb⁻¹. The analysis covered a mass range from 250 GeV to 4.5 TeV and found no evidence of an excess anywhere in the spectrum. Upper mass limits were set at 95% CL on both model- specific benchmark new physics signals and on two different generic resonance forms: a Gaussian shape and a Breit-Wigner shape which accounted for pdf and detector effects. The analysis excluded excited quarks below 4.06, heavy <i>W'</i> bosons below 2.45, colour-octet scalars below 2.70, leptophobic chiral excited bosons <i>W^*</i> below 1.75, and quantum black holes below 5.66 and 5.62 for the Qbh and BlackMax generators respectively.

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There is no abstract available for this dissertation.

This thesis reports an investigation on the feasibility study of a searching mechanism using an APP suitable for an on-line bibliographic retrieval, operation, especially for retrospective searches. From the study of the searching methods used in the conventional systems it is seen that elaborate file- and data- structures are introduced to improve the response time of the system. These consequently lead to software and hardware redundancies. To mask these complexities of the system an expensive computer with higher capabilities and more powerful instruction set is commonly used. Thus the service of the systen becomes cost-ineffective. On the other hand the primitive operations of a searching mechanism, such as, association, domain selection, intersection and unions, are the intrinsic features of an associative parallel processor. Therefore it is important to establish the feasibility of an APP as a cost-effective searching mechanise. In this thesis a searching mechanism using an 'ON-THE-FLY' searching technique has been proposed. The parallel search unit uses a Byte-oriented VRL-APP for efficient character string processing. At the time of undertaking this work the specification for neither the retrieval systems nor the BO-VRL APP's were well established; hence a two-phase investigation was originated. In the Phase I of the work a bottom up approach was adopted to derive a formal and precise specification for the BO-VRL-APP. During the Phase II of the work a top-down approach was opted for the implementation of the searching mechanism. An experimental research vehicle has been developed to establish the feasibility of an APP as a cost-effective searching mechanism. Although rigorous proof of the feasibility has not been obtained, the thesis establishes that the APP is well suited for on-line bibligraphic information retrieval operations where substring searches including boolean selection and threshold weights are efficiently supported.

Les recherches passées constituent pourtant une source d'information utile pour les nouveaux utilisateurs (nouvelles requêtes). En raison de l'absence de collections ad-hoc de RI, à ce jour il y a un faible intérêt de la communauté RI autour de l'utilisation des recherches passées. En effet, la plupart des collections de RI existantes sont composées de requêtes indépendantes. Ces collections ne sont pas appropriées pour évaluer les approches fondées sur les requêtes passées parce qu'elles ne comportent pas de requêtes similaires ou qu'elles ne fournissent pas de jugements de pertinence. Par conséquent, il n'est pas facile d'évaluer ce type d'approches. En outre, l'élaboration de ces collections est difficile en raison du coût et du temps élevés nécessaires. Une alternative consiste à simuler les collections. Par ailleurs, les documents pertinents de requêtes passées similaires peuvent être utilisées pour répondre à une nouvelle requête. De nombreuses contributions ont été proposées portant sur l'utilisation de techniques probabilistes pour améliorer les résultats de recherche. Des solutions simples à mettre en œuvre pour la réutilisation de résultats de recherches peuvent être proposées au travers d'algorithmes probabilistes. De plus, ce principe peut également bénéficier d'un clustering des recherches antérieures selon leurs similarités. Ainsi, dans cette thèse un cadre pour simuler des collections pour des approches basées sur les résultats de recherche passées est mis en œuvre et évalué. Quatre algorithmes probabilistes pour la réutilisation des résultats de recherches passées sont ensuite proposés et évalués. Enfin, une nouvelle mesure dans un contexte de clustering est proposée. / Past searches provide a useful source of information for new users (new queries). Due to the lack of ad-hoc IR collections, to this date there is a weak interest of the IR community on the use of past search results. Indeed, most of the existing IR collections are composed of independent queries. These collections are not appropriate to evaluate approaches rooted in past queries because they do not gather similar queries due to the lack of relevance judgments. Therefore, there is no easy way to evaluate the convenience of these approaches. In addition, elaborating such collections is difficult due to the cost and time needed. Thus a feasible alternative is to simulate such collections. Besides, relevant documents from similar past queries could be used to answer the new query. This principle could benefit from clustering of past searches according to their similarities. Thus, in this thesis a framework to simulate ad-hoc approaches based on past search results is implemented and evaluated. Four randomized algorithms to improve precision are proposed and evaluated, finally a new measure in the clustering context is proposed.

The high time-resolution radio sky represents unexplored astronomical territory where the discovery potential is high. In this thesis I have studied the transient radio sky, focusing on millisecond scales. As such, this work is concerned primarily with neutron stars, the most populous member of the radio transient parameter space. In particular, I have studied the well known radio pulsars and the recently identified group of neutron stars which show erratic radio emission, known as RRATs, which show radio bursts every few minutes to every few hours. When RRATs burst onto the scene in 2006, it was thought that they represented a previously unknown, distinct class of sporadically emitting sources. The difficulty in their identification implies a large underlying population, perhaps larger than the radio pulsars. The first question investigated in this thesis was whether the large projected population of RRATs posed a problem, i.e. could the observed supernova rate account for so many sources. In addition to pulsars and RRATs, the various other known neutron star manifestations were considered, leading to the conclusion that distinct populations would result in a 'birthrate problem'. Evolution between the classes could solve this problem - the RRATs are not a distinct population of neutron stars. Alternatively, perhaps the large projected population of RRATs is an overestimate. To obtain an improved estimate, the best approach is to find more sources. The Parkes Multi-beam Pulsar Survey, wherein the RRATs were initially identified, offered an opportunity to do just this. About half of the RRATs showing bursts during the survey were thought to have been missed, due to the deleterious effects of impulsive terrestrial interference signals. To remove these unwanted signals, so that we could identify the previously shrouded RRATs, we developed new interference mitigation software and processing techniques. Having done this, the survey was completely re-processed, resulting in the discovery of 19 new sources. Of these, 12 have been re-detected on multiple occasions, whereas the others have not been seen to re-emit since the initial discovery observations, and may be very low burst-rate RRATs, or, isolated burst events. These discoveries suggest that the initial population estimate was not over-estimated - RRATs, though not a distinct population, are indeed numerous. In addition to finding new sources, characterisation of their properties is vital. To this end, a campaign of regular radio observations of the newly discovered sources, was mounted, at the Parkes Observatory, in Australia. In addition, some of the initially identified RRATs were observed with the Lovell Telescope at Jodrell Bank. These have revealed glitches in J1819-1458, with anomalous post-glitch recovery of the spin-down rate. If such glitches were common, it would imply that the source was once a magnetar, neutron stars with the strongest known magnetic fields of up to 10¹⁵ gauss. The observations have also been used to perform 'timing' observations of RRATs, i.e. determination of their spin-down characteristics. At the beginning of this thesis, 3 of the original sources had 'timing solutions' determined. This has since risen to 7, and furthermore, 7 of the newly discovered sources now also have timing solutions. With this knowledge, we can see where RRATs lie in period-period derivative space. The Parkes RRATs seem to be roughly classifiable into three groupings, with high observed nulling fractions - normal pulsars, high magnetic field pulsars and old, 'dying' pulsars. It seems that RRATs and pulsars are one and the same. When a pulsar is more easily detected in searches for single bright pulses, as opposed to in periodicity searches, we label it a RRAT. Such searches impart a selection effect on the parameter space of possible sources, in both nulling fraction and rotation period. In this sense, an observational setup could be designed to make any pulsar appear as a RRAT. For realistic survey parameters however, this is not the case, and the groups mentioned above seem to be the most likely to appear as RRATs. In fact, we can utilise RRAT searches to identify neutron stars, difficult to find by other means, in particular high-magnetic field pulsars, and pulsars approaching the pulsar "death valley". Some of the RRATs are well explained as being distant/weak pulsars with a high modulation index, others seem to be nulling pulsars. This highlights the incomplete knowledge of nulling behaviour in the pulsar population. It seems that there may be a continuum of nulling durations, under a number of guises, from 'nulling pulsars' to 'RRATs' to 'intermittent pulsars'. In fact this nulling may fit into the emerging picture, whereby pulsar magnetospheres switch between stable configurations.

Submitted by Biblioteca Central (biblioteca@unicap.br) on 2018-02-27T17:34:51Z No. of bitstreams: 2 ana_catharine_rodrigues_pereira_lima.pdf: 1121866 bytes, checksum: 228e573cd677159ade0979f5d3a0c43d (MD5) license_rdf: 0 bytes, checksum: d41d8cd98f00b204e9800998ecf8427e (MD5) / Made available in DSpace on 2018-02-27T17:34:51Z (GMT). No. of bitstreams: 2 ana_catharine_rodrigues_pereira_lima.pdf: 1121866 bytes, checksum: 228e573cd677159ade0979f5d3a0c43d (MD5) license_rdf: 0 bytes, checksum: d41d8cd98f00b204e9800998ecf8427e (MD5) Previous issue date: 2017-12-04 / This is the present research of a meta-analysis about the duty of procedural cooperation exercised from three specialized periodicals in Procedural Law. Leaning over the scientific articles of the Journal of Process, the Dialectic Processes Journal and the Brazilian Journal of Procedural Law, this study try to find answer the question that inaugurated it: how the Brazilian civil procedural literature dealt with the duty of procedural cooperation, in the period between 1989 and 2017? In force of the Federal Constitution of 1988 defined the choice of the initial frame of this research. Under the hypothesis that there would be a uniformity of treatment in the published studies on procedural cooperation in the Brazilian civil procedural literature, as well as the possibility of these studies having developed as a consequence of the legal provision that started to provide for procedural cooperation in form expressed in the CPC of 2015, it was sought to identify, in the literature accessed when and in what way the topic of procedural cooperation was treated, as well as the number of times it was approached, as well as the immediate criteria for analyzing the data collected. Therefore, the research evolution stages were carried out according to the phases that the meta-analysis requires to be effectively carried out. The dogmatic chapters developed aim only to access the foundations necessary to the knowledge and identification of the proposed research problem. Some distinctions and similarities were observed in the way the studies published in the periodicals dealt with the researched subject, among other situations. We then defined categories of analysis in relation to the data collection, and, once applied in the interpretative graphs of these data, we pointed out the results of the research. This paper does not aim to position itself on the subject researched, but only presents an overview that can serve to guide and adapt future studies, considering that it can diagnose if there are excesses or gaps, superficiality or deepening, among other factors, in the studies published by the analyzed journals. It may also contribute to the development of future academic research on the same theme, insofar as the results found by this research can be accessed, for example, before a literature review, pointing out, from the results found here, which journals should be accessed, considering how the topic was treated. For these reasons, the work presented here may become an instrument of consultation for future studies on procedural cooperation, which may have the expense of research time possibly minimized. / Trata-se a presente pesquisa de uma meta-análise acerca do dever de cooperação processual exercido a partir de três periódicos especializados em Direito Processual Civil. Debruçando-se sobre os artigos científicos da Revista de Processo, da Revista Dialética de Processo e da Revista Brasileira de Direito Processual, este estudo buscou resposta ao questionamento que o inaugurou: como a literatura processual civil brasileira tratou o dever de cooperação processual, no período compreendido entre o ano de 1989 e 2017? A vigência da Constituição Federal de 1988 definiu a escolha do marco inicial dessa pesquisa. Sob as hipóteses de que haveria uma uniformidade de tratamento nos estudos publicados, acerca da cooperação processual, na literatura processual civil brasileira, bem como a possibilidade desses estudos terem se desenvolvido em consequência do dispositivo legal que passou a prever o dever de cooperação processual de forma expressa, no CPC de 2015, buscou-se, identificar na literatura acessada quando e de que maneira o tema cooperação processual foi tratado, bem como a quantidade de vezes em que fora abordado, assim também, os critérios imediatos para análise dos dados coletados. Para tanto, foram exercidos estágios de evolução da pesquisa de acordo com as fases que a meta-análise exige para que seja eficazmente efetuada. Os capítulos dogmáticos desenvolvidos visam apenas a acessar os fundamentos necessários ao conhecimento e à identificação do problema de pesquisa proposto. Observaram-se algumas distinções e diversas semelhanças na forma como os estudos publicados nos periódicos tratavam o tema pesquisado, dentre outras situações. Definiram-se, então, categorias de análise face à coleta dos dados, e, uma vez aplicados nos gráficos interpretativos desses dados, apontaram-se os resultados da pesquisa. Este trabalho não visa a posicionar-se acerca da temática pesquisada, mas apenas apresentar um panorama que pode servir ao direcionamento e à adequação de futuros estudos, considerando-se que poderá diagnosticar se há excessos ou lacunas, superficialidade ou aprofundamento, dentre outros fatores, nos estudos publicados pelos periódicos analisados. Poderá também, contribuir para o desenvolvimento de futuras pesquisas acadêmicas acerca da mesma temática, na medida em que poderão ser acessados os resultados encontrados por essa pesquisa, por exemplo, diante de uma revisão de literatura, apontando-se, a partir dos resultados aqui encontrados, quais periódicos deveriam ser acessados, tendo em vista como a temática foi tratada. Por tais razões, poderá tornar-se, o trabalho ora apresentado, um instrumento de consulta para os próximos estudos acerca da cooperação processual, que poderão ter o dispêndio de tempo de pesquisa possivelmente minimizado.

Le Modèle Standard de la physique des particules est un modèle décrivant très bien les particules élémentaires et leurs interactions mais plusieurs raisons motivent les physiciens à rechercher de la physique au-delà de ce modèle. La supersymétrie correspond à une des extensions les plus prometteuses. La thèse est axée sur deux sujets, et repose sur les données acquises en 2015 et 2016 avec le détecteur ATLAS du LHC (CERN):La première partie est un travail de performance permettant d'améliorer la mesure de l'énergie des jets de particules. Ces objets sont générés par l'hadronisation des quarks et des gluons par interaction nucléaire forte et sont difficiles à reconstruire. Ma contribution correspond à la dernière étape et repose entièrement sur les données. La méthode se base sur les mesures effectuées sur les photons qui servent d'objets de référence. Mon travail a consisté à mettre en place la méthode, estimer les corrections en énergie et évaluer les incertitudes. Les corrections obtenues sont de l'ordre de 2-3% en fonction de l'énergie des jets. L'incertitude sur l'échelle en énergie des jets est estimée à environ 1% pour les trois types de jets étudiés. Les résultats sont actuellement utilisés par la collaboration ATLAS. Cette méthode permet également de mesurer la résolution en énergie des jets du détecteur. Une résolution de l'ordre de 17%-22% est obtenue à 40 GeV en fonction du type de jet étudié, et 4% à 1 TeV, avec une incertitude de l'ordre de 10%.La deuxième partie de la thèse porte sur la recherche d'un signal de supersymétrie. Le signal recherché correspond à la production d'une paire de squarks ou de gluinos et comprend des jets et de l'énergie transverse manquante dans l'état final. Mon travail porte principalement sur l'optimisation des critères de sélections en se basant sur plusieurs modèles simplifiés de supersymétrie. Neuf nouvelles régions de signal ont été introduites dans l'analyse. Les limites tracées au cours du Run 1 sur la masse des squarks et gluinos ont ainsi été augmentées pour atteindre une valeur maximale respective de l'ordre de 1.6 TeV et 2 TeV sur les modèles étudiés. / The Standard Model of particle physics is a very precise model describing the elementary particles and their interactions. However, some issues lead physicists to search for physics beyond the Standard Model. Supersymmetry is an extension of the Standard Model providing solutions to the current issues. In this thesis, results are obtained using the data collected in 2015 and 2016 with the ATLAS detector at the LHC (CERN). The thesis is based in two parts:The first part is a performance analysis improving the energy measurement of high energy objects called "jets". They are generated by the hadronization of quarks and gluons in the detector via the strong nuclear interaction. My contribution is the last step of the the reconstruction and calibration chain and is fully based on data. The method uses the very precise measurement of the photon energy, and provides corrections to the jet energy scale. My contribution consists in set-up the method, estimate the corrections, measure the jet energy scale and evaluate the uncertainties. Corrections are at the order of 2-3% as a function of the jet energy scale. The uncertainty of the jet energy scale is estimated to be at the order of 1% for the three jet types. Results are now used by the ATLAS Collaboration. This method is also used to estimate the jet energy resolution. A resolution at the order of 17%-22% at 40 GeV depending on the jet type, and 4% at 1 TeV is obtained with an uncertainty at the order of 10%.The second part of the thesis corresponds to the search for supersymmetry. The signal corresponds to a pair of supersymmetric particles called squarks and gluinos and corresponds to jets and missing transverse energy in the final state. My contribution mainly corresponds to the optimisation of the selections using several simplified models of supersymmetry. Nine signal regions have been introduced in the analysis. Limits on the mass of squarks and gluinos computed during the Run 1 have been greatly improved to reach a maximal value respectively at the order of 1.6 TeV and 2 TeV.