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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.
161

Reconnaissance automatique des entités nommées arabes et leur traduction vers le français / Automatic recognition of Arabic named entities and their translation into French

Fehri, Héla 17 December 2012 (has links)
La traduction des Entités Nommées (EN) est un axe de recherche d'actualité vu la multitude des documents électroniques échangés à travers Internet. Ainsi, le besoin de traiter ces documents par des outils de TALN est devenu nécessaire et intéressant. La modélisation formelle ou semi formelle de ces EN peut intervenir dans les processus de reconnaissance et de traduction. En effet, elle permet de rendre plus fiable la constitution des ressources linquistiques, de limiter l'impact des spécificités linguistiques ct de faciliter les transformations d'une représentation à une autre. Dans ce contexte, nous proposons un outil de reconnaissance ct de traduction vers le français des EN arabes basé essentiellement sur une représentation formelle et sur un ensemble de transducteurs. L'outil prend en compte l'intégration d'un module de translittération. L'implémentation de cet outil a été effectuée en utilisant la plateforme NooJ. Les résultats obtenus sont satisfaisants / The translation of named entities (NEs) is a current research topic with regard to the proliferation of electronic documents exchanged through the Internet. So, the need to process these documents with NLP tools becomes necessary and interesting. Formal or semi-formal modeling of these NEs may intervene in both processes of recognition and translation. Indeed, it makes the accumulation of linguistic resources more reliable, limits the impact of linguistic specificities and facilitates the transformation from one representation to another. In this context, we propose a tool for the recognition and translation of Arabic NEs into French, based primarily on formal .representation and a set of transducers. This tool takes into account the integration of a module of transliteration. Its implementation was performed using the NooJ platform and the results obtained proved to be satisfactory
162

Vliv facilitačního kinesio tapingu v oblasti dolních fixátorů lopatek na bolestivost spoušťových bodů v m. trapezius pars descendens / The Effect of Facilitating Kinesio Taping of lower scapula fixators on pain threshold of trigger points in the m. trapezius pars descendens

Bahenská, Eva January 2013 (has links)
Name: The Effect of Facilitating Kinesio Taping of lower scapula fixators on pain threshold of trigger points in the m. trapezius pars descendens Objectives: This study is a pilot study. The goal of this study is to determine effects of Facilitating Kinesio Taping of lower scapula fixators on painfulness of trigger points in the m. trapezius pars descendens. Methods: The study took place in a private medical office with thirteen patients. All of these patients were physically examined using standard tests of physiotherapy. Patients were measured using a pressure algometer to assess trigger points as painful. They reported the intensity of pain on VAS. The places of measurement were trigger points one and two in the muscle according Travell and Simons. Data were analyzed using the statistical program SPSS 15.0 and Microsoft Office Excel. Results: This study had three hypotheses. In the case of the first hypothesis, I concluded that KT has an effect on the pain threshold and its application will reduce the pain threshold in m.trapezius pars descendens. Statistical significance was the value of p = 0.03 and p = 0.011, the value of material significance (101.31 kPa and 106.7 kPa) confirmed my theory that after KT will increase the pressure of 100 kPa in the TrP1 and TrP2. In the second hypothesis, it...
163

The Optimal trigger speed of vehicle activated signs

Jomaa, Diala January 2014 (has links)
The thesis aims to elaborate on the optimum trigger speed for Vehicle Activated Signs (VAS) and to study the effectiveness of VAS trigger speed on drivers’ behaviour. Vehicle activated signs (VAS) are speed warning signs that are activated by individual vehicle when the driver exceeds a speed threshold. The threshold, which triggers the VAS, is commonly based on a driver speed, and accordingly, is called a trigger speed. At present, the trigger speed activating the VAS is usually set to a constant value and does not consider the fact that an optimal trigger speed might exist. The optimal trigger speed significantly impacts driver behaviour. In order to be able to fulfil the aims of this thesis, systematic vehicle speed data were collected from field experiments that utilized Doppler radar. Further calibration methods for the radar used in the experiment have been developed and evaluated to provide accurate data for the experiment. The calibration method was bidirectional; consisting of data cleaning and data reconstruction. The data cleaning calibration had a superior performance than the calibration based on the reconstructed data. To study the effectiveness of trigger speed on driver behaviour, the collected data were analysed by both descriptive and inferential statistics. Both descriptive and inferential statistics showed that the change in trigger speed had an effect on vehicle mean speed and on vehicle standard deviation of the mean speed. When the trigger speed was set near the speed limit, the standard deviation was high. Therefore, the choice of trigger speed cannot be based solely on the speed limit at the proposed VAS location. The optimal trigger speeds for VAS were not considered in previous studies. As well, the relationship between the trigger value and its consequences under different conditions were not clearly stated. The finding from this thesis is that the optimal trigger speed should be primarily based on lowering the standard deviation rather than lowering the mean speed of vehicles. Furthermore, the optimal trigger speed should be set near the 85th percentile speed, with the goal of lowering the standard deviation.
164

Correlação clínica e termográfica do ponto-gatilho miofascial nos músculos da mastigação / Thermographic and clinical correlation of myofascial trigger points in the masticatory muscles

Haddad, Denise Sabbagh 09 August 2011 (has links)
A síndrome dolorosa miofascial (SDM) é uma disfunção musculoesquelética não articular caracterizada por pontos-gatilho miofasciais. Estes pontos, identificados por meio da palpação, são descritos como bandas tensas na fibra muscular, podendo apresentar dor referida à compressão. Sabe-se que os pontos-gatilho miofasciais provocam hiperatividade simpática regional de temperatura local devido à atividade vasoconstritora cutânea. Para documentação objetiva por imagem desta alteração funcional, a termografia tem sido proposta como método auxiliar diagnóstico. O objetivo deste estudo foi correlacionar os exames clínico e termográfico dos pontos-gatilho nos músculos da mastigação masseter e temporal parte anterior. A amostra constituiu-se por 26 mulheres voluntárias com 41 ± 15 anos. Os resultados demonstraram correlação diretamente proporcional entre algometria e termografia na avaliação do ponto-gatilho miofascial, onde, quanto menor a força aplicada, menor a temperatura local (p<0,001). As áreas com dor referida apresentaram níveis de limiar de dor à pressão (1.28±0.45 kgf) menores quando comparados às áreas de dor local (1.73±0,59 kgf; p<0.001). Sendo assim, a imagem termográfica de um ponto-gatilho apresentou-se hiporradiante quando comparada à região de ausência de ponto-gatilho (&#916;T>0,4ºC; p<0.001). Além disso, a avaliação termográfica dos pontos-gatilho nos músculos masseter e temporal pelo gradiente térmico (&#916;T e &#916;&#952;) apresentou maior sensibilidade e especificidade em comparação com a temperatura absoluta (T), mesmo quando corrigidos estes valores para a temperatura ambiente e temperatura timpânica da voluntária durante o exame (&#952;). A termografia isoladamente identificou pontos-gatilho com sensibilidade de 62,5% e especificidade de 71,31%. Os autores concluíram que a termografia é um método de imagem não invasivo, com potencial de identificação de pontos-gatilho miofasciais na região facial. / Myofascial pain syndrome is a myalgic dysfunction characterized by myofascial trigger points (MTP). The taut band is a constant feature of a trigger point characterized by referred pain when stimulated. It is known that the myofascial trigger points cause regional sympathetic hyperactivity in local temperature due to the cutaneous vasoconstrictor activity. For detection of functional changes, thermography may be used as an auxiliary diagnostic imaging. The aim of this study was to correlate clinical and thermographic myofascial trigger points in the masticatory muscles masseter and temporalis. Twenty six women volunteers were included, having a mean age of 41 ± 15 years. The results showed directly proportional relationship by algometry and thermography in the assessment of MTP, where smaller the force applied, lower the local temperature will be (p<0.001). Moreover, when the soreness was evaluated and local vasomotor response, the temperature decreases as the worst local situation. PPT (pressure pain threshold) levels measured at the points of referred pain in MTP (1.28±0.45 kgf) were significantly lower than the areas of local pain in MTP (1.73±0,59 kgf; p<0.001). Thus, the thermographic image of a MTP presented colder than the area without trigger point (&#916;T>0,4ºC; p<0.001). In the thermographic assessment of MTP in the masseter and temporalis muscles, the results suggest that the parameters of thermal asymmetry (&#916;T and &#916;&#952;) show greater sensitivity and specificity in comparison to local absolute temperature values (T), even when corrected for the volunteer\'s core temperature and the temperature of the room during the exam (&#952;). Thermography can identify trigger points (referred pain) with sensitivity of 62,50% and specificity of 71,31%. The authors concluded that thermography is a noninvasive imaging method with potential for screening patients with MTP in the facial region.
165

Dor miofascial plantar e inervação do músculo abdutor do hálux: relação anátomo-clínica / Plantar miosfacial pain and inervation of the abductor hallucis muscle: and clinical- anatomy relationship

Wada, Juliano Takashi 22 May 2018 (has links)
A síndrome da dor miofascial crônica é a causa mais frequente das dores musculoesqueléticas com prevalência mundial que varia entre 13,7% e 47% da população, destes, em torno de 17% apresentam dores na região do retropé medial. O músculo abdutor do hálux que se localiza na região medial do pé representa grande importância para as síndromes dolorosas plantares, seu estudo será importante para compreender melhor a fisiopatologia da dor miofascial que ainda permanece desconhecida. Objetivos: Descrição dos pontos de penetração dos ramos do nervo plantar medial no ventre do músculo abdutor do hálux através da dissecção anatômica e a sua inter-relação com os sintomas clínicos de dor plantar nos pacientes ortopédicos. Método: O estudo foi realizado em dois grupos com a amostra calculada pelo projeto piloto realizado anteriormente. No grupo de dissecção anatômica (GDA) foram dissecados 30 pés para a avaliação do número de pontos de entrada dos ramos nervosos no músculo associado ao grupo dos pacientes ortopédicos (GPO) onde 30 pés com sintomas de dor no retropé medial foram submetidos à avaliação da sensibilidade dolorosa com o dolorímetro digital de pressão. Ambos os grupos utilizaram o referencial dos quadrantes no músculo abdutor do hálux. O GDA foi submetido a análise de equações de estimação generalizadas com distribuição Poisson e função de log logaritmo seguida de comparações múltiplas de Bonferroni assim como no GPO mas para a distribuição normal e função de ligação identidade, os dados foram expressos em média ± desvio padrão. O nível de significância foi ajustado para 5% (p < 0,05). Resultados: Neste estudo o GDA apresentou uma diferença estatisticamente significante de pontos de entrada dos ramos do nervo plantar medial no ventre muscular do abdutor do hálux no primeiro quadrante (póstero-lateral, Q1, p < 0,05) em relação aos demais quadrantes, assim como no GPO onde Q1 também apresentou uma maior sensibilidade dolorosa quando comparado aos demais quadrantes (p < 0,05). Foi registrado a partir das dissecções uma inédita fixação no osso navicular do músculo abdutor do hálux. Conclusão: Nossos resultados sugerem que existe uma possível relação entre o maior número de entrada dos ramos do nervo plantar medial no ventre do músculo abdutor do hálux e a maior sensibilidade dolorosa no retropé medial, ou seja, os problemas musculares podem desencadear sintomas clínicos dolorosos a partir da compressão nervosa na região. Os dados vão cooperar para a melhor compreensão das síndromes miofasciais dos pés que auxiliarão para o desenvolvimento de futuros tratamentos / Chronic myofascial pain syndrome is the most frequent cause of musculoskeletal pain, with a worldwide prevalence ranging from 13.7% to 47% of the population, which 17% have pain in the retromedial area. The abductor hallucis muscle is located in the medial region of the foot represent high importance for plantar painful syndromes and your study will be important to better understand the pathophysiology of myofascial pain that remains unknown. Objectives: Description through anatomical dissection of the penetration points of the medial plantar nerve branches in the abductor hallucis muscle layer and their interrelationship with the clinical symptoms of plantar pain in orthopedic patients. Methods: The study was carried out in two groups, the sample size was calculated by the previous pilot study. In the anatomical dissection group (ADG), 30 feet were dissected for the evaluation of the number of entry points of the nerve branches in the muscle belly associated with the orthopedic patients group (OPG) where 30 feet with pain symptoms were submitted to the evaluation of pain sensitivity with digital pressure gauge, both groups used the quadrants referential in the abductor hallucis muscle for the evaluation. The ADG were submitted to the analysis of generalized equation of estimation with Poisson distribuition and log logarithnm and was followed by Bonferroni multiple comparisons, for OPG the same analysis but for normal distribution and identity link function, the datas were expressed as mean ± standard deviation. The level of significance was adjusted to 5% (p < 0.05) for all tests. Results: In this study, the ADG presented a statistically significant difference of medial plantar nerve branches entry points in the first quadrant (posterolateral, Q1) in the abductor halluccis muscle (p < 0.05) in relation to the others, as well as in the OPG, where the first quadrant (Q1) also presented a greater pain sensitivity when compared to the other quadrants (p < 0.05). It was recorded an unprecedented navicular bone fixation from abductor hallucis muscle. Conclusion: Our results suggests that there are a possible relationship between the greater number of entry of the medial plantar nerve branches in the abductor hallucis muscle and the higher pain sensation in the retromedial plantar area and the muscle can trigger an nervous compression to develop painful symptoms. These datas will cooperate to better understand myofascial pain syndromes that will help to develop new treatments
166

Trigger and reconstruction farms in the HERA-B experiment and algorithms for a Third Level Trigger

Schwanke, Ullrich 30 October 2000 (has links)
Das HERA-$B$-Experiment am Deutschen Elektronen-Synchrotron (DESY) in Hamburg dient der Untersuchung der Physik von Teilchen, die $b$-Quarks enthalten. Der Schwerpunkt des Ex\-pe\-ri\-mentes liegt auf der Messung der CP-Verletzung im System der neutralen $B$-Mesonen. Es wird erwartet, dass die pr\"azise Bestimmung der CP-Asymmetrie im Zerfallskanal $B^0(\bar{B}^0)\to J/\psi K_S^0$ gro{\ss}en Einfluss auf die Weiterentwicklung des Standardmodells der Elementarteilchenphysik und g\"angiger kosmologischer Theorien haben wird. Das HERA-$B$-Experiment nutzt den Protonenstrahl des HERA-Ringes, um in Kollisionen mit einem feststehenden Target paarweise $B$-Hadronen zu erzeugen. Die Wechselwirkungen werden in einem Vorw\"artsspektrometer mit etwa 600.000 Auslesekan\"alen nachgewiesen. Aufgrund der relativ niedrigen Schwerpunktsenergie von 41.6\,GeV sind Ereignisse mit $b$-Quarks im Vergleich zu Wechselwirkungen mit leichteren Quarks um etwa sechs Gr\"o{\ss}enordnungen unterdr\"uckt. Die Selektion von Signalereignissen stellt daher eine besondere Herausforderung dar. Sie wird von einem vierstufigen Datennahme- und Triggerystem \"ubernommen, das die Ereignisrate von 10\,MHz auf etwa 20\,Hz reduziert. Neben speziell entwickelter Elektronik werden im Triggersystem mehrere hundert handels\"ubliche PCs eingesetzt. Die Computer sind in zwei so genannten PC-Farmen mit jeweils mehr als 200 Prozessoren angeordnet, die die Rechenkapazit\"at f\"ur Triggerentscheidungen und die prompte Analyse der Ereignisdaten zur Verf\"ugung stellen. Auf der einen Farm laufen schnelle Triggerprogramme mit einer Rechenzeit von etwa 1--100\,ms pro Ereignis ab. Die andere Farm rekonstruiert die Ereignisse online, bevor die Daten auf Band dauerhaft archiviert werden. Die pro Ereignis aufgewandte Rechenzeit liegt dabei im Bereich einiger Sekunden. Die vorliegende Arbeit behandelt zwei Themenkreise. Einerseits wird die technische Umsetzung der Trigger- und der Rekonstruktionsfarm beschrieben. Besonderes Augenmerk liegt dabei auf den Software-Systemen, die den Farmen erforderliche Kalibrationsdaten verf\"ugbar machen und die zentrale \"Uberwachung der Ergebnisse der ablaufenden Programme gestatten. Der Hauptteil der Arbeit besch\"aftigt sich mit Algorithmen f\"ur eine dritte Triggerstufe, die zus\"atzlich zu existierenden Programmen auf der Triggerfarm zum Einsatz kommen sollen. Der Zerfall $B^0(\bar{B}^0)\to J/\psi X$ hat eine sehr klare Signatur, wenn das $J/\psi$ in ein $e^+e^-$- oder $\mu^+\mu^-$-Paar zerf\"allt. Im Triggersystem wird nach einem Paar entgegengesetzt geladener Leptonen des gleichen Typs gesucht, deren invariante Masse der des $J/\psi$ entspricht und deren Spuren von einem gemeinsamen Vertex in der N\"ahe des Targets ausgehen. Es wird davon ausgegangen, dass die Ausnutzung aller kinematischen Zwangsbedingungen ausreicht, um diesen Zerfallskanal klar von Untergrundereignissen zu trennen. Die dritte Triggerstufe soll dagegen auf Signalprozesse mit weniger kinematischen Beschr\"ankungen angewandt werden. Solche Ereignisse entstehen zum Beispiel dann, wenn zwei in der Proton-Target-Kollision erzeugte $B$-Mesonen semileptonisch zerfallen. Das Triggersystem selektiert lediglich die beiden Leptonen, die aber hier nicht von einem gemeinsamen Vertex kommen. Die dritte Triggerstufe soll f\"ur derartige Zerfallstopologien innerhalb von 100\,ms pro Ereignis weitere Kriterien zur Unterscheidung von Signal- und Untergrundprozessen aus den Daten extrahieren. In der Arbeit wird anhand von Monte-Carlo-Studien untersucht, inwieweit die Daten des Silizium-Vertexdetektors des Experimentes zur Entscheidungsfindung einer dritten Triggerstufe beitragen k\"onnen. Dabei wird die Rekonstruktion von Spuren aus der Zerfallskaskade der $B$-Hadronen zus\"atzlich zu den von der vorhergehenden Triggerstufe selektierten Lep\-ton\-en an\-ge\-strebt. Mithilfe einer schnellen Mustererkennung f\"ur den Vertexdetektor wird gezeigt, dass das Auffinden aller Spuren und die Anwendung von Triggeralgorithmen innerhalb des vorgegebenen Zeitfensters von 100\,ms m\"oglich sind. Die Bestimmung der Spurparameter nahe der Targetregion macht von der Methode des Kalman-Filters Gebrauch, um der Vielfachstreuung im Detektormaterial Rechnung zu tragen. Dabei tritt das Problem auf, dass weder der Impuls der gefundenen Spuren bekannt ist, noch die Materialverteilung im Vertexdetektor aus Zeitgr\"unden in aller Strenge ber\"ucksichtigt werden kann. Durch geeignete N\"aherungen gelingt es, eine ausreichende Genauigkeit f\"ur die Spurparameter zu erreichen. Die aufgefundenen Teilchen bilden den Ausgangspunkt f\"ur Triggeralgorithmen. Hierbei wird untersucht, welche Methoden am besten geeignet sind, um Signal- und Unter\-grund\-ereignisse voneinander zu trennen. Es erweist sich, dass das Auffinden von Spuren mit gro{\ss}em Impaktparameter aussichtsreichere Ans\"atze als eine Suche nach Sekund\"arvertices bietet. / The HERA-$B$ experiment at Deutsches Elektronen-Synchrotron (DESY) Hamburg aims at investigating the physics of particles containing $b$ quarks. The experiment focusses on measuring CP violation in the system of neutral $B$ mesons. It is expected that the precise determination of the CP asymmetry in the channel $B^0(\bar{B}^0)\to J/\psi K_S^0$ will have an impact on the further development of the Standard Model of Elementary Particle Physics and cosmological theories. The HERA-$B$ experiment uses the proton beam of the HERA storage ring in fixed-target mode. $B$ hadrons are produced in pairs when protons from the beam halo interact with target nuclei. The interactions are recorded by a forward-spectrometer with roughly 600.000 readout channels. At the HERA-$B$ centre-of-mass energy of 42.6\,GeV, the $b\bar{b}$ cross section is only a tiny fraction of the total inelastic cross section. Only one in about 10$^6$ events contains $b$ quarks, which turns the selection of signal events into a particular challenge. The selection is accomplished by a four-stage data acquisition and trigger system reducing the event rate from 10\,MHz to about 20\,Hz. Besides custom-made electronics, several hundreds of PCs are used in the trigger system. The computers are arranged in two so-called PC farms with more than 200 processors each. The PC farms provide the computing capacity for trigger decisions and the prompt analysis of event data. One farm executes fast trigger programs with a computing time of 1--100\,ms per event. The other farm performs online reconstruction of the events before data are archived on tape. The computing time per event is in the range of several seconds. This thesis covers two topics. In the beginning, the technical implementation of the trigger and the reconstruction farm are described. In doing so, emphasis is put on the software systems which make calibration data available to the farms and which provide a centralised view on the results of the executing processes. The principal part of this thesis deals with algorithms for a Third Level Trigger. This trigger is to come into operation on the trigger farm together with existing programs. Processes of the type $B^0(\bar{B}^0)\to J/\psi X$ have a very clean signature when the $J/\psi$ decays to a $e^+e^-$ or $\mu^+\mu^-$ pair. The trigger system attempts to identify two unlike-sign leptons of the same flavour whose invariant mass matches the $J/\psi$. In later steps, the tracks are required to originate from a common vertex close to the target. It is assumed that these kinematic constraints are sufficient to pick out events of this type among the copious background processes. In contrast, the Third Level Trigger is to be applied to signal processes with fewer kinematic constraints. Such events occur for example when two $B$ mesons, which were created in a proton-target collision, decay semileptonically. The trigger system selects merely the two leptons which do not originate from a common vertex in this case. The Third Level Trigger has 100\,ms at its disposal to extract further criteria from the data which can serve to distinguish between signal and background events. This thesis investigates with the aid of Monte-Carlo simulations how the data of the experiment's silicon vertex detector can contribute to the decisions of a Third Level Trigger. The trigger aims at reconstructing tracks from the decay cascade of $B$ mesons in addition to the leptons selected by the preceding trigger levels. A fast pattern recognition for the vertex detector demonstrates that the reconstruction of all tracks and the application of trigger algorithms are possible within the given time slot of 100\,ms. The determination of track parameters in the target region exploits the Kalman-filter method to account for the multiple scattering of particles in the detector material. The application of this method is, however, made difficult by two facts. First, the momentum of the reconstructed tracks is not known. And, second, the material distribution in the detector cannot be taken into consideration in detail due to timing limitations. Adequate approximations for the momentum and the material traversed by a particle help to accomplish a sufficient accuracy of the track parameters. The reconstructed tracks constitute the starting point of several trigger algorithms, whose suitability to select signal events is investigated. Our studies indicate that the reconstruction of tracks with large impact parameters is a more promising approach than a search for secondary vertices.
167

Desenvolvimento de apalpador de contato elétrico (\"touch trigger probe\") para atuação no processo de torneamento / Devefopment of a low cost touch trigger probe for CNC lathes

Del Guerra, Marcelo 21 September 2004 (has links)
A utilização dos apalpadores acoplados a máquinas CNC se tornou uma realidade muito comum no mundo atual, principalmente devido à diminuição do tempo de preparação e possibilidades de realização de medições na própria máquina-ferramenta. Porém, ainda existem algumas barreiras a se transpor, como por exemplo, a dificuldade de programação, custo relativamente elevado e pouca literatura que trata exclusivamente a respeito da utilização dos apalpadores para medição nas máquinas-ferramentas. Nesse trabalho é realizada uma revisão bibliográfica sobre o uso dos apalpadores em ambiente industrial, discutindo-se as tecnologias utilizadas na geração do sinal de \"trigger\" e é proposto um novo modelo de apalpador de contato elétrico, de baixo custo, desenvolvido especialmente para atender as necessidades de medições em tornos CNC. Os testes em laboratório revelaram que a repetibilidade do protótipo construído foi de 0,003 mm dentro de uma confiabilidade de mais ou menos 3 \'sigma\' ou 99,73%. Concluiu-se que tais características são altamente compatíveis com os requisitos necessários para a maioria dos processos de torneamento. / The use of touch trigger probes attached to CNC machines has become a world standard, especially due the reduction of setup time and the ability to promote work piece measurements on machine. However, some barriers like measurement routines programming difficulties, high costs of these equipments and the low number of technical literature about this subject, still need to be transposed. This work presents a review on the applications of touch trigger probes on companies shop floor, discussing the nowadays technologies used to generate the trigger signal. A new touch trigger probe model based on a simple electrical contact is specially developed to provide the measuring characteristics required for Lathes, with the needed characteristics and low cost. The tests of the probe developed in the laboratory shown a repeatability of 0,003 mm (more and less 3 \'sigma\' or 99,73%). Those characteristics are high compatible with the most needs of the industry.
168

Observation du boson de Higgs dans sa désintégration en gamma+gamma et recherche de sa désintégration en Z+gamma avec le détecteur ATLAS / Observation of the Higgs particle in gamma+gamma events and search for the Higgs particle in Z+gamma events at ATLAS

Liu, Kun 24 June 2014 (has links)
Ce travail de thése concerne la recherche du boson de Higgsa laide de canaux de désinégration contenant des photons dans létat final, baée sur les données enregistrées par le détecteur ATLAS en 2011 et 2012, a une énergie dans le centre de masse des collisions proton-proton center-mass-energy et 8 TeV. La sélection deséévenements, les principaux bruits de fond, les propriéés du signal, la discrimination statistique entre signal et bruits de fond, ainsi que l'interprétation des ésultats en terme de boson de Higgs du moéle standard sont discués. Dans le canal de désinégration H to gamma+gamma, un excés par rapport au niveau de bruit de fond est clairement visible a une masse mH=126,8 +- 0,2(stat) +- 0,7(syst) GeV et avec une significativité locale de7,4 sigma. En revanche, dans le canal de désinégration rareH to Z+gamma, aucun excés n'est obseré dans la feétre de masse allant de 120 a 150 GeV. Ce résultat est interpéé comme une limiteégalea 11 fois la valeur de la section efficace de production pp to H to Z+gamma prédite par le moéle standard pour une masse du boson de Higgs de mH = 125,5 GeV, proche de celle mesurée dans les canaux engamma+gamma et en quatre leptons. Une reconstruction et une identification efficace des photons, ainsi qu'une connaissance précise des performances du systéme de éclenchement et de l'algorithme d'identification, sont des aspects importants de ces mesures. Une grande partie de ce manuscrit est ainsi consacréea la description de l'optimisation de ces performances et des activités de mesures que j'ai réalisées pendant ces trois années. / This thesis focuses on the searches for the Higgs boson in events with photons in the final states, using the full proton-proton collision data collected by ATLAS at center-mass-energy of 7 TeV and 8 TeV in 2011 and 2012.Higgs boson decays to photon pairs or to a photon and a Z boson decaying to di-electrons or di-muons are investigated. The event selection, the main backgrounds, the signal properties, and the statistical discrimination between the signal and background in data and the interpretation of the results in terms of a Standard Model Higgs boson are discussed. In the H decays to diphoton channel a clear excess over the background is seen at a mass of mH= 126.8 +- 0.2(stat) +- 0.7(syst) GeV, with a local significance of 7.4 sigma. In the rare decay channel H decays to Z+gamma no evidence of excess over the background is observed in the mass range 120-150 GeV, and, for a Higgs boson mass near the one obtained from the combined mass measurement in the diphoton and 4-lepton final states, mH=125.5 GeV, an upper limit of 11 times the SM prediction, at 95% confidence level, is set on the production cross section times the H to Z+gamma cross section. One of the most important ingredient for these measurements is the efficient reconstruction and identification of photons, and a precise knowledge of the trigger and identification performance. A significant part of the document is thus devoted to the photon performance optimisation and measurement activities that I carried on in the past three years.
169

METHODOLOGIE DE DEVELOPPEMENT ET DE MODELISATION UML DES SYSTEMES D'ACQUISITION ET DE TRAITEMENT EN TEMPS REEL POUR LES EXPERIENCES DE PHYSIQUE DES HAUTES ENERGIES

Anvar, Shebli 13 September 2002 (has links) (PDF)
La complexité croissante des systèmes d'acquisition et de traitement en temps réel (TDAQ) pour les expériences de physique des hautes énergies appelle à une évolution ad hoc des outils de développement. Dans cet ouvrage, nous traitons de l'articulation entre la spécification de principe des systèmes TDAQ et leur conception/réalisation sur une plateforme matérielle et logicielle concrète. Notre travail repose sur la définition d'une méthodologie de développement des systèmes TDAQ qui réponde aux problématiques de développements particulières à ces systèmes. Il en résulte la spécification détaillée d'un « canevas méthodologique » basé sur le langage UML, destiné à encadrer un processus de développement. L'usage de ce canevas méthodologique UML doit permettre la mise en place progressive d'un canevas « maison », c'est-à-dire un atelier de développement comprenant des composants réutilisables et des éléments d'architecture génériques adaptés aux applications TDAQ. L'ouvrage s'articule autour de 4 sections principales. La section II est dévolue à la caractérisation et à l'évolution des systèmes TDAQ. En section III, nous nous intéressons aux technologies pertinentes pour notre problématique, notamment les techniques de réutilisation logicielle telles les motifs récurrents (design patterns) et les canevas (frameworks), avec une orientation en faveur des domaines du temps réel et de l'embarqué. Notre apport conceptuel spécifique est exposé en section IV, où nous procédons notamment à la spécification détaillée, formalisée et exemples à l'appui, de notre modèle de développement. Enfin, nous terminons notre propos en section V en évoquant le projet de R&D MORDICUS de mise en œuvre concrète de notre canevas méthodologique UML, ainsi que les développements récents de l'OMG (Object Management Group) sur l'architecture orientée modèles (Model Driven Architecture), particulièrement en résonance avec notre travail.
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Etude du système de déclenchement électronique pour le projet HL-LHC et recherche de nouvelle physique dans le spectre de masse invariante top anti-top au sein de l'expérience CMS du LHC

Beaupère, Nicolas 19 September 2012 (has links) (PDF)
Ce manuscrit décrit mon travail de thèse au sein de l'expérience CMS du collisioneur LHC. Il présente les deux sujets sur lesquels j'ai travaillé : un sujet orienté détecteur et un sujet orienté analyse de données. Le premier sujet, orienté détecteur, se situe dans le cadre du projet HL-LHC qui prévoit une augmentation de la luminosité instantanée d'un facteur cinq. Une telle augmentation et la conservation du système de haut niveau du déclenchement (HLT), engendre de nouvelles contraintes sur le détecteur CMS. Notamment au niveau du système de déclenchement électronique. La collaboration CMS envisage d'implanter ce dernier au sein du détecteur de traces. La méthode des mémoires associatives est proposée. Elle nécessite toutefois une présélection intelligente des signaux électriques pour être utilisable. La méthode de la largeur des amas est proposée pour présélectionner les signaux. L'optimisation de cette méthode, en particulier des paramètres géométriques des modules et des seuils appliqués pour la présélection des signaux électrique, est le résultat de mon travail. Il est détaillé tout au long de la partie III de ce manuscrit. Le deuxième sujet concerne l'analyse des données récoltées par CMS durant l'année 2011. Cette analyse a pour objectif de rechercher de nouvelles particules dans le spectre de masse invariante top anti-top. De par sa grande masse, proche de la brisure électrofaible, le quark top joue un rôle prépondérant dans de nombreuses extensions du Modèle Standard. L'observation de résonances étroites dans le spectre pourrait en être le signe. L'analyse est subdivisée en trois parties : la sélection des évènements top anti-top, la reconstruction de la masse invariante top anti-top et une étude statistique pour quantifier la présence de nouvelle physique. Les résultats de ce travail sont des limites sur la section efficace de production de nouvelles particules. Ils sont présentés dans la partie IV du manuscrit.

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