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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

Medida da seção de choque difrativa simples dσ/d|t| a √s = 8 TeV no experimento CMS / Measurement of single diffractive cross section dσ/d|t| a √s = 8 TeV using the CMS experiment

Lina Milena Huertas Guativa 16 July 2013 (has links)
Coordenação de Aperfeiçoamento de Pessoal de Nível Superior / A análise descrita nesta dissertação tem como objetivo a medida da seção de choque difrativa d&#963;/d|t| à energia no sistema do centro de massa de &#8730;s = 8 TeV. Os eventos usados para obter a seção de choque difrativa foram selecionados para processos de difração simples com um próton espalhado na região frontal e na região cinemática de 0,03 <|t| < 1,0 GeV e 0,03 < &#958; < 0.1, usando os dados em comum obtidos em 2012 dos detectores CMS e TOTEM, o qual permite ter uma perspectiva mais detalhada do processo difrativo, devido à aceitação completa que oferece a combinação dos detectores. Os dados foram corrigidos devido à aceitação e eficiência do detector. A partir de uma parametrização exponencial da forma Ae ^Bt, o valor da inclinação do processo em que o próton espalhado é detectado em ambas as direções positiva da CMS é de B= -6,403 1,241 GeV- . / The goal of the analysis presented in this dissertation is the measurement of the diffractive cross section d&#963;/d|t| at center of mass energy of &#8730;s = 8 TeV. The events were selected for single diffractive processes with one scattering proton in the forward region and the kinematic region of 0,03 <|t| < 1,0 GeV e 0,03 < &#958; < 0.1, using the data collected during 2012 by both the CMS and TOTEM detectors, whose joint acceptance allows a more detailed perspective of the diffractive processes. The data were corrected for the effects of detector acceptance and efficiency. Since the exponential parametrization Ae ^Bt was fit to data, the value obtained for the slope for a precess when the scattering proton is detected in both positive or negative regions of CMS is of B= -6,403 1,241 GeV- .
22

Supervision des réseaux pair à pair structurés appliquée à la sécurité des contenus

Cholez, Thibault 23 June 2011 (has links) (PDF)
L'objectif de cette thèse est de concevoir et d'appliquer de nouvelles méthodes de supervision capables d'appréhender les problèmes de sécurité affectant les données au sein des réseaux P2P structurés (DHT). Ceux-ci sont de deux types. D'une part les réseaux P2P sont utilisés pour diffuser des contenus illégaux dont l'activité est difficile à superviser. D'autre part, l'indexation des contenus légitimes peut être corrompue (attaque Sybil). Nous proposons tout d'abord une méthode de supervision des contenus basée sur l'insertion de sondes et le contrôle du mécanisme d'indexation du réseau. Celle-ci permet d'attirer l'ensemble des requêtes des pairs pour un contenu donné, puis de vérifier leur intention en générant des appâts très attractifs. Nous décrivons ainsi les faiblesses du réseau permettant la mise en œuvre de notre méthode en dépit des protections existantes. Nous présentons les fonctionnalités de notre architecture et en évaluons l'efficacité sur le réseau P2P KAD avant de présenter un déploiement réel ayant pour but l'étude des contenus pédophiles. Nous considérons ensuite la sécurité des données indexées dans une DHT. Nous supervisons le réseau KAD et montrons que celui-ci est victime d'une pollution particulièrement néfaste affectant 2/3 des fichiers mais aussi de nombreuses attaques ciblées affectant la sécurité des contenus stockés. Nous proposons un moyen de détecter efficacement cette dernière attaque en analysant la distribution des identifiants des pairs autour d'une référence ainsi qu'une contre-mesure permettant de protéger les pairs à un coût négligeable. Nous terminons par l'évaluation de la protection au sein de réseaux P2P réels.
23

Medida da seção de choque difrativa simples d&#963;/d|t| a &#8730;s = 8 TeV no experimento CMS / Measurement of single diffractive cross section d&#963;/d|t| a &#8730;s = 8 TeV using the CMS experiment

Lina Milena Huertas Guativa 16 July 2013 (has links)
Coordenação de Aperfeiçoamento de Pessoal de Nível Superior / A análise descrita nesta dissertação tem como objetivo a medida da seção de choque difrativa d&#963;/d|t| à energia no sistema do centro de massa de &#8730;s = 8 TeV. Os eventos usados para obter a seção de choque difrativa foram selecionados para processos de difração simples com um próton espalhado na região frontal e na região cinemática de 0,03 <|t| < 1,0 GeV e 0,03 < &#958; < 0.1, usando os dados em comum obtidos em 2012 dos detectores CMS e TOTEM, o qual permite ter uma perspectiva mais detalhada do processo difrativo, devido à aceitação completa que oferece a combinação dos detectores. Os dados foram corrigidos devido à aceitação e eficiência do detector. A partir de uma parametrização exponencial da forma Ae ^Bt, o valor da inclinação do processo em que o próton espalhado é detectado em ambas as direções positiva da CMS é de B= -6,403 1,241 GeV- . / The goal of the analysis presented in this dissertation is the measurement of the diffractive cross section d&#963;/d|t| at center of mass energy of &#8730;s = 8 TeV. The events were selected for single diffractive processes with one scattering proton in the forward region and the kinematic region of 0,03 <|t| < 1,0 GeV e 0,03 < &#958; < 0.1, using the data collected during 2012 by both the CMS and TOTEM detectors, whose joint acceptance allows a more detailed perspective of the diffractive processes. The data were corrected for the effects of detector acceptance and efficiency. Since the exponential parametrization Ae ^Bt was fit to data, the value obtained for the slope for a precess when the scattering proton is detected in both positive or negative regions of CMS is of B= -6,403 1,241 GeV- .
24

Accessing intangible technologies through experimental archaeology : a methodological analysis

Schenck, Tine January 2015 (has links)
This thesis concerns the relationship between research in experimental archaeology and the intangible of the past. Only a quarter of technological experiments in a sample of 100 studies addresses the intangible of technological practice, and this project sets out to explore if there are conceptual or practical obstacles for this low rate. The thesis begins with an in-depth examination of experimental archaeology and the criteria, paradigms and theories that determine its practice. Through this study, elements of the dichotomy positivism/postmodernism are uncovered and discussed. To resolve this dualism, a third paradigm – philosophical pragmatism – is introduced as an alternative. This conceptual debate represents Part I, and is subsequently collated into a methodological framework for the creation of a typified experiment. Part II consists of the experimental segment of this study, in search for practical obstacles for the exploration of the intangible. Through experimenting with Iron Age Bucket-shaped pots, Mesolithic faceted pebbles and Middle Palaeolithic birch bark tar production, different components of an experiment are highlighted for investigation. An element that comes forward as problematic is the relationship between experimental archaeologists and science ideals that is underscored by experimental tradition. Conclusively, the final discussion leaves the conceptual and practical barriers that may prevent archaeologists from studying the intangible aspects of technology overturned. In sum, this may enable experimental archaeologists to take a fuller view of their own practice and that of the people of the past.
25

Alert correlation towards an efficient response decision support / Corrélation d’alertes : un outil plus efficace d’aide à la décision pour répondre aux intrusions

Ben Mustapha, Yosra 30 April 2015 (has links)
Les SIEMs (systèmes pour la Sécurité de l’Information et la Gestion des Événements) sont les cœurs des centres opérationnels de la sécurité. Ils corrèlent un nombre important d’événements en provenance de différents capteurs (anti-virus, pare-feux, systèmes de détection d’intrusion, etc), et offrent des vues synthétiques pour la gestion des menaces ainsi que des rapports de sécurité. La gestion et l’analyse de ce grand nombre d’alertes est une tâche difficile pour l’administrateur de sécurité. La corrélation d’alertes a été conçue afin de remédier à ce problème. Des solutions de corrélation ont été développées pour obtenir une vue plus concise des alertes générées et une meilleure description de l’attaque détectée. Elles permettent de réduire considérablement le volume des alertes remontées afin de soutenir l’administrateur dans le traitement de ce grand nombre d’alertes. Malheureusement, ces techniques ne prennent pas en compte les connaissances sur le comportement de l’attaquant, les fonctionnalités de l’application et le périmètre de défense du réseau supervisé (pare-feu, serveurs mandataires, Systèmes de détection d’intrusions, etc). Dans cette thèse, nous proposons deux nouvelles approches de corrélation d’alertes. La première approche que nous appelons corrélation d’alertes basée sur les pots de miel utilise des connaissances sur les attaquants recueillies par le biais des pots de miel. La deuxième approche de corrélation est basée sur une modélisation des points d’application de politique de sécurité / Security Information and Event Management (SIEM) systems provide the security analysts with a huge amount of alerts. Managing and analyzing such tremendous number of alerts is a challenging task for the security administrator. Alert correlation has been designed in order to alleviate this problem. Current alert correlation techniques provide the security administrator with a better description of the detected attack and a more concise view of the generated alerts. That way, it usually reduces the volume of alerts in order to support the administrator in tackling the amount of generated alerts. Unfortunately, none of these techniques consider neither the knowledge about the attacker’s behavior nor the enforcement functionalities and the defense perimeter of the protected network (Firewalls, Proxies, Intrusion Detection Systems, etc). It is still challenging to first improve the knowledge about the attacker and second to identify the policy enforcement mechanisms that are capable to process generated alerts. Several authors have proposed different alert correlation methods and techniques. Although these approaches support the administrator in processing the huge number of generated alerts, they remain limited since these solutions do not provide us with more information about the attackers’ behavior and the defender’s capability in reacting to detected attacks. In this dissertation, we propose two novel alert correlation approaches. The first approach, which we call honeypot-based alert correlation, is based on the use of knowledge about attackers collected through honeypots. The second approach, which we call enforcement-based alert correlation, is based on a policy enforcement and defender capabilities’ model
26

Registered Dietitian Nutritionists' Knowledge, Education, Impressions, and Utilization of Treatments Regarding Postural Orthostatic Tachycardia Syndrome

McSwords, Kayla M. 18 April 2023 (has links)
No description available.
27

Parent-Child Dyadic Experiences Living with Postural Orthostatic Tachycardia Syndrome (POTS) during Emerging Adulthood

Farchtchi, Masumeh Auguste 08 May 2020 (has links)
Chronic illness and invisible disability are impactful contexts during emerging adulthood and the launching stage of the family life cycle (Beatty, 2011; Capelle, Visser, and Vosman, 2016; Young et al., 2010). The parent-child relationship is important to both developmental and health outcomes in families coping with chronic illness during emerging adulthood (Crandell, Sandelowski, Leeman, Haville, and Knafle, 2018; Fenton, Ferries, Ko, Javalkar, and Hooper, 2015; Waldboth, Patch, Mahrer-Imhaf, and Metcalfe, 2016). While informed clinical competency in counseling families experiencing disablement is a diversity-affirmative ethical imperative among psychotherapists (Mona et al., 2017), little is known in family therapy about how parents and emerging adult children experience launching with chronic illness. This qualitative study explored the parent-child dyadic experience of living with a chronic illness called Postural Orthostatic Tachycardia Syndrome (POTS) during emerging adulthood. Seven dyads of parents and their emerging adult children with POTS were interviewed. Data analysis of in-depth interviews using Moustakas's (1994) transcendental phenomenology uncovered eight thematic clusters of meaning in the shared lived experience of POTS at the launching stage of the family life cycle. Clinical implications for family therapists were explored using Rolland's family system-illness (FSI) model of medical family therapy. Study limitations and future directions for further research were discussed. / Master of Science / More and more young adults are living with chronic illness. Postural Orthostatic Tachycardia Syndrome (POTS) is a little-known chronic illness that tends to begin during adolescence. Like many health problems that disproportionately affect women, POTS is often overlooked by doctors. POTS symptoms, such as dizziness and cognitive difficulty, impact a person's ability to engage in preferred activities and identities. Family therapists can play an impactful role in supporting parents and children with POTS through developmental tasks related to launching an emerging adult in the context of this complex and widely misunderstood chronic illness. This thesis presented the first qualitative study of parent-child dyadic experiences living with POTS. Clinical implications for medical family therapy were highlighted. To construct an interview framework, Rolland's Family Systems-Illness (FSI) clinical model for helping families cope with illness and disability was used in conjunction with Arnett's description of emerging adulthood as a developmental stage in life. Seven parent-child dyads were interviewed for 1-2 hours in fourteen separate interviews generating transcripts about 140,000 words long in total. Analysis of these interviews identified shared themes composing the essence of the parent-child experience living with POTS during emerging adulthood. Results were described through tables and narratives. Clinical implications for family therapists working with parents and children with POTS during emerging adulthood were proposed. Limitations and ideas for future studies were discussed.
28

Étude des déterminants moléculaires associés à l’intolérance orthostatique dans la pathogenèse de l’encéphalomyélite myalgique

Leveau, Corinne 12 1900 (has links)
L’encéphalomyélite myalgique (EM) est une maladie complexe, multi-systémique et débilitante, dont l’étiologie est inconnue. D’une personne atteinte d’encéphalomyélite myalgique (PAEM) à l’autre, les symptômes varient en fréquence et en sévérité créant ainsi une grande hétérogénéité clinique entre les individus. Un sous-groupe de PAEM vivent des épisodes d’intolérance orthostatique (IO) ou vivent avec une comorbidité de syndrome de tachycardie orthostatique posturale (POTS), deux conditions qui sont mal comprises. Le malaise après-effort (PEM), un des symptômes phare de l’EM, survient après une activité physique ou mentale minimale. Le malaise après-effort entraîne une dégradation générale de l’état de l’individu, peut entraîner une exacerbation des autres symptômes et va durer de plusieurs heures à plusieurs jours. Chez les individus souffrant de POTS ou d’IO, le malaise après-effort peut déclencher des épisodes d’intolérance orthostatique. Le gène SLC6A2 codant pour le transporteur de norépinephrine NET a été identifié comme potentiel mécanisme dans pathophysiologie du POTS, tout comme les protéines impliquées dans la vasodilatation, comme la thrombospondine-1 (TSP-1). Notre laboratoire a identifié un panel de onze microARN (miARN) exprimés différentiellement chez les PAEM. Parmi ceux-ci, le miR-150-5p a comme cible prédite SLC6A2. Notre hypothèse était qu’une plus grande expression du miR-150-5p après un effort ou qu’une chute de thrombospondine-1 pourrait induire une vasodilatation soudaine contribuant aux symptômes d’IO ou de POTS. Nous avons mesuré les niveaux plasmatiques du miR-150-5p et de TSP-1 avant (T0) et après (T90) l’induction du malaise après-effort chez des PAEM avec POTS/IO (n = 20), chez des PAEM sans POTS/IO (n = 117) et chez des témoins sédentaires associés pour le sexe et l’âge (n = 48). Nous avons démontré que les sujets atteints de POTS/IO avaient des niveau plus importants du miR-150-5p et des symptômes plus sévères. Finalement, nous avons également utilisé la veste intelligente Hexoskin (Carré Technologies Inc., Montreal, Qué., Canada) pour suivre un sous-groupe d’individus (n = 10) sur une plus longue période après l’induction du malaise après-effort. Avec cet outil, nous avons pu monitorer les symptômes au quotidien, permettant un meilleur suivi clinique de ces patients. Ce projet de maîtrise a permis une meilleure compréhension de la pathophysiologie de l’EM et de celle du POTS. / Myalgic encephalomyelitis (ME) is a complex chronic disease with debilitating smyptoms and unknown etiology. Symptoms vary in frequency and severity from a person with ME (PwME) to another, thus creating a highly clinically heterogeneous patient population. Some PwME also experience orthostatic intolerance (OI) episodes or live with a comorbidity of postural orthostatic tachycardia syndrome (POTS), two conditions that are not well understood. Post-exertional malaise (PEM) causes patients to experience a worsening of their symptoms following an effort, whether it be physical or mental. PEM can last from a few hours to several days. In PwME with POTS/OI, PEM can trigger orthostatic intolerance episodes. SLC6A2 is a gene coding for the norepinephrine transporter NET. Its contribution to the POTS pathophysiology has been mentioned several times in literature. A biochemical milieu prone to vasodilation was also reported as a contributing element to POTS pathophysiology. Recently, our laboratory published an article identifying a panel of eleven microRNAs (miRNAs) differentially expressed in PwME. Among these miRNAs, miR-150-5p has been predicted to target SLC6A2. Our hypothesis was that higher expression of miR-150-5p following an effort or a decrease in circulating thrombospondin-1 (TSP-1) inducing vasodilation could contribute to POTS/OI symptoms. We measured circulating levels of miR-150-5p and TSP-1 before (T0) and after (T90) PEM induction in PwME (n = 117), PwME with POTS/OI (n = 20) and age and sex matched sedentary controls (n = 48). We demonstrated that PwME with POTS/OI have higher levels of miR-150-5p at both T0 and T90, while also having more severe symptoms. Furthermore, we used the connected vest Hexoskin (Carré Technologies Inc., Montreal, Qué., Canada) to follow a subgroup (n = 10) of patients for a longer period following PEM induction. With this tool, we were able to monitor symptoms on a daily basis, allowing better clinical follow-up. Overall, this project allowed better understanding of ME and POTS’ pathophysiology.
29

La protection des systèmes informatiques vis à vis des malveillances

Nicomette, Vincent 19 November 2009 (has links) (PDF)
La sécurité des systèmes informatiques répartis est un problème de plus en plus important, en particulier avec l'utilisation massive du réseau Internet. Il est donc essentiel de pouvoir imaginer des techniques de protection efficaces de nos systèmes et de nos réseaux. Ces travaux proposent une contribution à la protection des systèmes informatiques vis-a-vis des malveillances, en abordant le problème sous deux angles : un angle architectural et un angle expérimental. L'angle architectural concerne la conception d'architectures de sécurité permettant de faire face aux menaces actuelles, en proposant plusieurs approches suivies dans la cadre de différentes thèses. L'angle expérimental se focalise sur des techniques permettant d'améliorer notre connaissance des attaquants et des processus d'attaques, en particulier, les processus qui utilisent le réseau Internet comme support.
30

Supervision des réseaux pair à pair structurés appliquée à la sécurité des contenus / Monitoring of structured P2P networks applied to the security of contents

Cholez, Thibault 23 June 2011 (has links)
L'objectif de cette thèse est de concevoir et d'appliquer de nouvelles méthodes de supervision capables d'appréhender les problèmes de sécurité affectant les données au sein des réseaux P2P structurés (DHT). Ceux-ci sont de deux types. D'une part les réseaux P2P sont utilisés pour diffuser des contenus illégaux dont l'activité est difficile à superviser. D'autre part, l'indexation des contenus légitimes peut être corrompue (attaque Sybil).Nous proposons tout d'abord une méthode de supervision des contenus basée sur l'insertion de sondes et le contrôle du mécanisme d'indexation du réseau. Celle-ci permet d'attirer l'ensemble des requêtes des pairs pour un contenu donné, puis de vérifier leur intention en générant des appâts très attractifs. Nous décrivons ainsi les faiblesses du réseau permettant la mise en oeuvre de notre méthode en dépit des protections existantes. Nous présentons les fonctionnalités de notre architecture et en évaluons l'efficacité sur le réseau P2P KAD avant de présenter un déploiement réel ayant pour but l'étude des contenus pédophiles.Nous considérons ensuite la sécurité des données indexées dans une DHT. Nous supervisons le réseau KAD et montrons que celui-ci est victime d'une pollution particulièrement néfaste affectant 2/3 des fichiers mais aussi de nombreuses attaques ciblées affectant la sécurité des contenus stockés. Nous proposons un moyen de détecter efficacement cette dernière attaque en analysant la distribution des identifiants des pairs autour d'une référence ainsi qu'une contre-mesure permettant de protéger les pairs à un coût négligeable. Nous terminons par l'évaluation de la protection au sein de réseaux P2P réels. / The purpose of this thesis is to design and implement new monitoring solutions which are able to deal with the security issues affecting data stored in large structured P2P networks (DHT). There are two major types of issues. First, P2P networks are used to spread illegal contents whose activity is difficult to monitor accurately. Second, the indexation of regular contents can be corrupted (Sybil attack).We first designed a new approach to monitor contents based on the insertion of distributed probes in the network to take control of the indexation mechanism. The probes can attract all the related requests for a given content and assess the peers intent to access it by generating very attractive honeypots. We describe the weaknesses of the network allowing our solution to be effective despite recent protection mechanisms. We then present the services offered by our monitoring architecture and we evaluate its efficiency on KAD. We also present a real deployment whose purpose is to study pedophile contents on this network.Then, we focus on data integrity in distributed hash tables. We performed large scale monitoring campaigns on the KAD network. Our observations show that it suffers from a very harmful pollution of its indexation mechanism affecting 2/3 of the shared files and from a large number of localized attacks targeting contents. To mitigate these threats, we propose a new efficient way to detect attacks by analysing the distribution of the peers' ID found around an entry after a DHT lookup and a counter-measure which can protect the peers at a negligible cost. Finally, we evaluate our solution in real P2P networks.

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