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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.
151

日中同形二字漢字語の品詞性の対応関係に関する考察

TAMAOKA, Katsuo, XIONG, Kexin, 玉岡, 賀津雄, 熊, 可欣 11 November 2014 (has links)
No description available.
152

Betydelsen av socialt stöd för upplevelsen av psykisk ohälsa : En kvalitativ socialpsykologisk studie som omfattar åtta individer i ett kommunalt rehabiliteringsprojekt

Svensson, Simon, Fransson, Mattias January 2014 (has links)
Med denna socialpsykologiska studie ville vi få en ökad förståelse för vad socialt stöd upplevdesbetyda för rehabiliterande individers syn på sin psykiska ohälsa. De åtta intervjuernagenomfördes i anslutning till ett rehabiliteringsprojekt för personer med psykisk ohälsa i enav Sveriges kommuner. De intervjuade personerna var inskrivna i rehabiliteringsprojektet ochdeltog i dess aktiviteter. Resultatet visade att dialoger med personer som hade erfarenhet avliknande psykisk ohälsa och professionella hade störst inverkan på individernas syn på sinpsykiska ohälsa. I analysen använde vi Goffmans teori om stigma, Meads teori om rollövertagandeoch Bubers dialogteori. Enligt analysen bidrog personer med liknande psykisk ohälsaoch professionella till vad vi kallar frigörande dialoger, där respondenterna kunde bli förståddaoch accepterade såsom de var. Betydelsen dessa personer hade för individernas förståelseoch acceptans menar vi baserades på deras förståelse genom sitt igenkännande och sittarbete. Vi menar att denna nivå av förståelse inte kunde fås av personer utan dessa egenskaper,oavsett vem det var, om inte kunskapen skaffades. / With this social psychological study we wanted to gain an increased understanding of whatimportance the social support had for how rehabilitative individuals' look at their mental illness.The eight interviews were conducted in a rehabilitation project for people with mentalillness in one of Sweden's municipalities. The people we interviewed were enrolled in the rehabilitationproject and participated in its activities. The result showed that dialogue withpeople who had experience from similar mental illness and professionals had greatest impacton how the respondents' looked at their mental illness. In the analysis, we used Goffman’stheory of stigma, Mead’s theory of role taking and Buber’s theory of dialogue between individuals.According to our analysis, people with similar mental health and professionals contributedto what we call liberating dialogues in which respondents could be understood andaccepted as they were. We mean that the significance these people had for the individual'sunderstanding and acceptance was based on their understanding by their recognition andwork. We mean that this understanding could not be obtained by any person without suchproperties, no matter who it was, if the knowledge wasn’t acquired.
153

O tratamento das demandas de massa nos Juizados Especiais Cíveis

Hermann, Ricardo Torres January 2010 (has links)
Submitted by Pedro Mizukami (pedro.mizukami@fgv.br) on 2011-01-05T18:04:47Z No. of bitstreams: 1 DMPPJ - RICARDO TORRES HERMANN.pdf: 1590905 bytes, checksum: 11f290b6ab97f7ec2a4f21474fa7e7c8 (MD5) / Approved for entry into archive by Pedro Mizukami(pedro.mizukami@fgv.br) on 2011-01-05T19:17:49Z (GMT) No. of bitstreams: 1 DMPPJ - RICARDO TORRES HERMANN.pdf: 1590905 bytes, checksum: 11f290b6ab97f7ec2a4f21474fa7e7c8 (MD5) / Made available in DSpace on 2011-01-06T12:26:39Z (GMT). No. of bitstreams: 1 DMPPJ - RICARDO TORRES HERMANN.pdf: 1590905 bytes, checksum: 11f290b6ab97f7ec2a4f21474fa7e7c8 (MD5) Previous issue date: 2010 / This thesis demonstrates that the Small Claims Courts have the calling for the resolution of individual conflicts. It notes, based on case study that, however, these courts are faced with a lot of collective demands which are jeopardizing the functioning of these legal channels. Thus, it is proposed to reflect what are the appropriate measures to deal with this problem. It notes that the use of the Public Civil Action (similar to Class Action) is still incipient in the country,  especially  in  the  case  of  homogeneous  individual  rights  ('direitos  individuais  homogêneos'). As a result, the paper points out the need to encourage the protection of such collective rights and how the class actions can absorb the individual actions that continue to be  proposed  on  those  issues.  It  concludes  that  individual  homogeneous  rights  ('direitos  individuais homogêneos') can be considered typical collective rights (broadly) and should be protected by the Class Action. This study establishes that it is necessary to include a legal provision to give only to Public Civil Action Courts the competence to conduct concurrent individual and collective disputes, avoiding that they be proposed in the Small Claims Courts, because it’s not possible to use their own mechanisms of Public Civil Actions in these courts. It also indicates the importance of establishing the absolute competence of Small Claims Courts as a way of defining their appropriate expertise and formulate directions for handling the demands of mass, whether they are of collective or individual nature. / A presente dissertação visa demonstrar que os Juizados Especiais Cíveis apresentam vocação para resolução de conflitos individuais. Verifica, com base em estudo de caso, que apesar disso, defrontam-se esses juizados com uma grande quantidade de demandas coletivas as quais vêm comprometendo o bom funcionamento dessas vias jurisdicionais. Assim, propõe-se a refletir quais as medidas adequadas para o enfrentamento desse problema. Constata que a utilização do processo coletivo ainda é incipiente no país, especialmente no que se refere aos direitos individuais homogêneos. Em virtude disso, aponta a necessidade de se incentivar a tutela de tais direitos coletivos e de que maneira podem os processos coletivos absorver as ações individuais que continuam a ingressar sobre essas mesmas questões. Conclui que os direitos individuais homogêneos podem ser considerados típicos direitos coletivos (lato sensu), devendo ser tutelados no juízo comum. Estabelece ainda que é necessário fazer constar disposição legal que atribua exclusivamente ao juízo comum a tramitação concomitante de litígios individuais e coletivos, evitando que ingressem nos Juizados Especiais Cíveis, por não ser neles possível recorrer aos mecanismos próprios do Processo Coletivo. Indica também a importância de se instituir a competência absoluta como forma de definição da competência adequada desses Juizados Especiais Cíveis e formula um roteiro para o tratamento das demandas de massa, seja as de natureza coletiva, seja as de índole individual.
154

A critical analysis of equal remuneration claims in South African law

Ebrahim, Shamier 20 July 2015 (has links)
The legislation relating to equal remuneration claims is an area of law which is nuanced and consequently poorly understood. It has posed an unattainable mountain for many claimants who came before the South African courts. This is as a direct result of the lack of an adequate legal framework providing for same in the Employment Equity Act 55 of 1998. The case law recognises two causes of action relating to equal remuneration. The first cause of action is equal remuneration for the same/similar work. The second is equal remuneration for work of equal value. The former is easily understood by both claimants and courts but the latter is poorly understood and poses many difficulties. The aim of this dissertation is fourfold. Firstly, the problems and criticisms regarding equal remuneration claims will be briefly highlighted. Secondly, a comprehensive analysis of the current legal framework will be set out together with the inadequacies. Thirdly, an analysis of international law and the law of the United Kingdom relating to equal remuneration claims will be undertaken. Fourthly, this dissertation will conclude by proposing recommendations to rectify the inadequacies. / Mercantile Law / LL.M. (Labour law)
155

Efeito de um extrato de ervas sobre a ingestão alimentar e concentrações de grelina acilada e peptídeo semelhante ao glucagon 1 em mulheres com excesso de peso / Effect of herbal extract on food intake and acylated ghrelin concentrations and glucagon-like peptide 1 in women who are overweight

Celestino, Marina Monteiro 05 February 2016 (has links)
Submitted by Cássia Santos (cassia.bcufg@gmail.com) on 2016-06-02T12:58:47Z No. of bitstreams: 2 Dissertação - Marina Monteiro Celestino - 2016.pdf: 3038939 bytes, checksum: f658681fb77c19cdbec1ee83ee51b443 (MD5) license_rdf: 23148 bytes, checksum: 9da0b6dfac957114c6a7714714b86306 (MD5) / Approved for entry into archive by Luciana Ferreira (lucgeral@gmail.com) on 2016-06-02T14:50:30Z (GMT) No. of bitstreams: 2 Dissertação - Marina Monteiro Celestino - 2016.pdf: 3038939 bytes, checksum: f658681fb77c19cdbec1ee83ee51b443 (MD5) license_rdf: 23148 bytes, checksum: 9da0b6dfac957114c6a7714714b86306 (MD5) / Made available in DSpace on 2016-06-02T14:50:30Z (GMT). No. of bitstreams: 2 Dissertação - Marina Monteiro Celestino - 2016.pdf: 3038939 bytes, checksum: f658681fb77c19cdbec1ee83ee51b443 (MD5) license_rdf: 23148 bytes, checksum: 9da0b6dfac957114c6a7714714b86306 (MD5) Previous issue date: 2016-02-05 / Coordenação de Aperfeiçoamento de Pessoal de Nível Superior - CAPES / Overweight and obesity are associated with excessive food intake, due to changes in the productions of gastrointestinal hormones productions. Objectives: To evaluated the effect of a herbal extract derived from native species of South America on food intake, acylated ghrelin concentrations and peptide similar to glucagon 1. Material and methods: A randomized, blind, placebo-controlled, crossover design methodology, with intervention in two days with an interval (washout) seven days, consisted of 20 overweight women. Three capsules a mix of herbal medicines were administered, containing 112 mg of yerba mate, guarana 95 mg and 36 mg of damiana, or three placebo capsules containing 100 mg of lactose. The herbal extract was administered 15 minutes before a standardized breakfast (494.50 kcal, carbohydrates 52.67%, 12.91% protein and 34.5% lipid) and a standard lunch (632.05 kcal, 61, 67% carbohydrates, 16.97% protein and 21.44% lipid) for all patients. Food not eaten by the participants was weighed to evaluated food intake. Blood samples were collected at baseline and on days 45, 60, 90, 150, 210 minutes after breakfast in the morning and lunch for determination of plasma glucose concentrations, acylated ghrelin and peptide similar to glucagon 1. To compare the differences of the mean energy food intake and macronutrient was performed paired t-test, for the behavior of hormones was performed ANOVA and was calculated area under the curve and to determine the differences between the areas was performed Student's t test. Results: In the supplemented group, there was significant reduction in energy intake at lunch and macronutrients in both meals (p <0.05). The acylated ghrelin concentrations were lower after breakfast (p <0.05) and glucagon-like peptide 1 were higher (p <0.05) after breakfast in the supplemented group. Conclusion: Supplementation with herbal mix reduced energy intake and macronutrients by the modulating hormones glucagon-like 1 and acylated ghrelin in overweight and obesity women. / O excesso de peso se relaciona com a ingestão alimentar excessiva, decorrente de alterações nas produções de hormônios gastrointestinais. Objetivos: Avaliar o efeito de um extrato de ervas oriundos de espécies nativas da América do Sul sobre a ingestão alimentar, as concentrações de grelina acilada e peptídeo semelhante ao glucagon 1. Material e métodos: Ensaio clínico randomizado cego, crossover com intervenção em dois dias, com intervalo (washout) de sete dias, composto por 20 mulheres adultas com excesso de peso. Foram administradas três cápsulas de um extrato de ervas, contendo 112 mg de erva-mate, 95 mg de guaraná e 36 mg de damiana, ou três cápsulas de placebo, contendo 100 mg de lactose. O extrato de ervas foi administrado 15 minutos antes de um desjejum padronizado (494,50 kcal, 52,67% carboidratos, 12,91% proteínas e 34,5% lipídios) e de um almoço padronizado (632,05 kcal, 61,67% carboidratos, 16,97% proteínas e 21,44% lipídios) para todas pacientes. Os alimentos não ingeridos pelos participantes foram pesados para avaliar a ingestão alimentar. Foram coletadas amostras de sangue no início do estudo e nos tempos de 45, 60, 90, 150, 210 minutos após o café-da-manhã e almoço para determinação das concentrações plasmáticas de glicose, grelina acilada e peptídeo semelhante ao glucagon 1. Para comparar as diferenças das médias da ingestão alimentar energética e de macronutrientes foi realizado o teste t pareado, para o comportamento dos hormônios foi realizado ANOVA e foi calculado a área abaixo da curva e para determinar as diferenças entre as áreas foi realizado teste T de Student. Resultados: No grupo suplementado, foi observada redução significativa da ingestão energética no almoço e de macronutrientes em ambas as refeições (p < 0,05). As concentrações de grelina acilada foram menores após o almoço (p <0,05) e de peptídeo semelhante ao glucagon 1 foram maiores (p < 0,05) após o desjejum no grupo suplementado. Conclusão: A administração do extrato de ervas reduziu a ingestão calórica e de macronutrientes sugerindo que possa ter ocorrido por meio da modulação da ação dos hormônios peptídeo semelhante ao glucagon 1 e grelina acilada em mulheres com sobrepeso e obesidade.
156

Wald tests for IV regression with weak instruments

Vilela, Lucas Pimentel 17 September 2013 (has links)
Submitted by Lucas Pimentel Vilela (lvilela@fgvmail.br) on 2013-10-07T17:22:14Z No. of bitstreams: 2 Dissertação Final.pdf: 665295 bytes, checksum: b54a14202e41e19e863a73328cfb2123 (MD5) Supplement.pdf: 2259071 bytes, checksum: 19718d483c50f35f3878c81521b0acf9 (MD5) / Approved for entry into archive by Janete de Oliveira Feitosa (janete.feitosa@fgv.br) on 2013-10-08T21:33:30Z (GMT) No. of bitstreams: 2 Dissertação Final.pdf: 665295 bytes, checksum: b54a14202e41e19e863a73328cfb2123 (MD5) Supplement.pdf: 2259071 bytes, checksum: 19718d483c50f35f3878c81521b0acf9 (MD5) / Approved for entry into archive by Marcia Bacha (marcia.bacha@fgv.br) on 2013-10-14T14:44:28Z (GMT) No. of bitstreams: 2 Dissertação Final.pdf: 665295 bytes, checksum: b54a14202e41e19e863a73328cfb2123 (MD5) Supplement.pdf: 2259071 bytes, checksum: 19718d483c50f35f3878c81521b0acf9 (MD5) / Made available in DSpace on 2013-10-14T14:45:02Z (GMT). No. of bitstreams: 2 Dissertação Final.pdf: 665295 bytes, checksum: b54a14202e41e19e863a73328cfb2123 (MD5) Supplement.pdf: 2259071 bytes, checksum: 19718d483c50f35f3878c81521b0acf9 (MD5) Previous issue date: 2013-09-17 / This dissertation deals with the problem of making inference when there is weak identification in models of instrumental variables regression. More specifically we are interested in one-sided hypothesis testing for the coefficient of the endogenous variable when the instruments are weak. The focus is on the conditional tests based on likelihood ratio, score and Wald statistics. Theoretical and numerical work shows that the conditional t-test based on the two-stage least square (2SLS) estimator performs well even when instruments are weakly correlated with the endogenous variable. The conditional approach correct uniformly its size and when the population F-statistic is as small as two, its power is near the power envelopes for similar and non-similar tests. This finding is surprising considering the bad performance of the two-sided conditional t-tests found in Andrews, Moreira and Stock (2007). Given this counter intuitive result, we propose novel two-sided t-tests which are approximately unbiased and can perform as well as the conditional likelihood ratio (CLR) test of Moreira (2003). / Esta dissertação trata do problema de inferência na presença de identificação fraca em modelos de regresso com variáveis instrumentais. Mais especificamente em testes de hipóteses com relação ao parâmetro da variável endógena quando os instrumentos são fracos. O principal foco é nos testes condicionais unilaterais baseados nas estatísticas de razão de máxima verossimilhança, score e Wald. Resultados teóricos e numéricos mostram que o teste t condicional unilateral baseado no estimador de mínimos quadrados em dois estágios tem uma boa performance mesmo na presença de instrumentos fracamente correlacionados com a variável endógena. A abordagem condicional corrige uniformemente o tamanho do teste t e quando a estatística F populacional é tão pequena quanto dois, o poder do teste é próximo ao power envelope tanto de testes similares quanto de não similares. Tal resultado é surpreendente visto a má performance dos testes t’s condicionais bilaterais relatada em (6, Andrews, Moreira and Stock (2007)). Dado esse resultado aparentemente contra intuitivo, apresentamos novos testes t’s condicionals bilaterais que são aproximadamente não viesados e performam, em alguns casos, tão bem quanto o teste condicional baseado na estatística de razão de verossimilhança de ( 19 , Moreira (2003)).
157

Ochrana dětské práce - výkon umělecké, kulturní, sportovní nebo reklamní činnosti dítěte / Protection of child labour - children's performance in artistic, cultural, sports or advertising activities

Vlach, Jan January 2015 (has links)
The topic of this thesis is "Protection of child labour - children's performance in artistic, cultural, sports or advertising activities". The first part of this thesis presents the historical excursion to the evolution of the legislation of the child labour in the Czech countries. The first rules on the protection of children at work were adopted already at the end of the 18th century, hovewer the greatest development came during the 19th century and in the days of the "First Republic". Since 1966, the regulation of the child labour was set in the Labour Code no. 65/1965 Coll., where endured (even after the adoption of the new Labour Code no. 262/2006 Coll.), until the adoption of the Civil Code no. 89/2012 Coll. The second part is focused on the international aspect of the protection of the child labour. At the global level, the United Nations and its Specialized Agencies and Programmes, such as the International Labour Organization and the United Nations Children's Fund (UNICEF) take the important part. Thanks to these institutions several key documents, such as The Convention on the Rights of the Child, 1989, ILO Convention No. 138 on the Minimum Age for Admission to Employment and Work, 1973, and ILO Convention No. 182 on the Worst Forms of Child Labour, 1999, have been adopted. Beside the...
158

Big data management for periodic wireless sensor networks / Gestion de données volumineuses dans les réseaux de capteurs périodiques

Medlej, Maguy 30 June 2014 (has links)
Les recherches présentées dans ce mémoire s’inscrivent dans le cadre des réseaux decapteurs périodiques. Elles portent sur l’étude et la mise en oeuvre d’algorithmes et de protocolesdistribués dédiés à la gestion de données volumineuses, en particulier : la collecte, l’agrégation etla fouille de données. L’approche de la collecte de données permet à chaque noeud d’adapter sontaux d’échantillonnage à l’évolution dynamique de l’environnement. Par ce modèle le suréchantillonnageest réduit et par conséquent la quantité d’énergie consommée. Elle est basée surl’étude de la dépendance de la variance de mesures captées pendant une même période voirpendant plusieurs périodes différentes. Ensuite, pour sauvegarder plus de l’énergie, un modèled’adpatation de vitesse de collecte de données est étudié. Ce modèle est basé sur les courbes debézier en tenant compte des exigences des applications. Dans un second lieu, nous étudions unetechnique pour la réduction de la taille de données massive qui est l’agrégation de données. Lebut est d’identifier tous les noeuds voisins qui génèrent des séries de données similaires. Cetteméthode est basée sur les fonctions de similarité entre les ensembles de mesures et un modèle defiltrage par fréquence. La troisième partie est consacrée à la fouille de données. Nous proposonsune adaptation de l’approche k-means clustering pour classifier les données en clusters similaires,d’une manière à l’appliquer juste sur les préfixes des séries de mesures au lieu de l’appliquer auxséries complètes. Enfin, toutes les approches proposées ont fait l’objet d’études de performancesapprofondies au travers de simulation (OMNeT++) et comparées aux approches existantes dans lalittérature. / This thesis proposes novel big data management techniques for periodic sensor networksembracing the limitations imposed by wsn and the nature of sensor data. First, we proposed anadaptive sampling approach for periodic data collection allowing each sensor node to adapt itssampling rates to the physical changing dynamics. It is based on the dependence of conditionalvariance of measurements over time. Then, we propose a multiple level activity model that usesbehavioral functions modeled by modified Bezier curves to define application classes and allowfor sampling adaptive rate. Moving forward, we shift gears to address the periodic dataaggregation on the level of sensor node data. For this purpose, we introduced two tree-based bilevelperiodic data aggregation techniques for periodic sensor networks. The first one look on aperiodic basis at each data measured at the first tier then, clean it periodically while conservingthe number of occurrences of each measure captured. Secondly, data aggregation is performedbetween groups of nodes on the level of the aggregator while preserving the quality of theinformation. We proposed a new data aggregation approach aiming to identify near duplicatenodes that generate similar sets of collected data in periodic applications. We suggested the prefixfiltering approach to optimize the computation of similarity values and we defined a new filteringtechnique based on the quality of information to overcome the data latency challenge. Last butnot least, we propose a new data mining method depending on the existing K-means clusteringalgorithm to mine the aggregated data and overcome the high computational cost. We developeda new multilevel optimized version of « k-means » based on prefix filtering technique. At the end,all the proposed approaches for data management in periodic sensor networks are validatedthrough simulation results based on real data generated by periodic wireless sensor network.
159

Hydrodynamic modelling of the shock ignition scheme for inertial confinement fusion / Modélisation hydrodynamique du schéma d'allumage par choc pour la fusion par confinement inertiel

Vallet, Alexandra 20 November 2014 (has links)
Le schéma d'allumage par choc pour la fusion par confinement inertiel utilise une impulsion laser intense à la fin d'une phase d'assemblage de combustible. Les paramètres clefs de ce schéma sont la génération d'une haute pression d'ablation, l'amplification de la pression du choc généré par un facteur supérieur à cent et le couplage du choc avec le point chaud de la cible. Dans cette thèse, de nouveaux modèles semi-analytiques sont développés afin de décrire le choc d'allumage depuis sa génération jusqu'à l'allumage du combustible. Tout d'abord, un choc sphérique convergent dans le coeur pré-chauffé de la cible est décrit. Le modèle est obtenu par perturbation de la solution auto-semblable de Guderley en tenant compte du nombre de Mach du choc élevé mais fini. La correction d'ordre un tient compte de l'effet de la force du choc. Un critère d'allumage analytique est exprimé en fonction de la densité surfacique du point chaud et de la pression du choc d'allumage. Le seuil d'allumage est plus élevé pour un nombre de Mach faible. Il est montré que la pression minimale du choc, lorsqu'il entre dans le coeur de la cible, est de 20Gbar. La dynamique du choc dans la coquille en implosion est ensuite analysée. Le choc se propage dans un milieu non inertiel avec un fort gradient de pression et une augmentation temporelle générale de la pression. La pression du choc est amplifiée plus encore durant la collision avec une onde de choc divergente provenant de la phase d'assemblage. Les modèles analytiques développés permettent une description de la pression et de la force du choc dans une simulation typique de l'allumage par choc. Il est démontré que, dans le cas d'une cible HiPER, une pression initiale du choc de l'ordre de 300 Mbar dans la zone d'ablation est nécessaire. Il est proposé une analyse des expériences sur la génération de chocs forts avec l'installation laser OMEGA. Il est montré qu'une pression du choc proche de 300Mbar est atteinte près de la zone d'ablation avec une intensité laser absorbée de l'ordre de 2 X 10(15) W.cm-2 et une longueur d'onde de 351 nm. Cette valeur de la pression est deux fois plus importante que la valeur attendue en considérant une absorption collisionnelle de l'énergie laser. Cette importante différence est expliquée par la contribution d'électrons supra-thermiques générés durant l'interaction laser/plasma dans la couronne. Les modèles analytiques proposés permettent une optimisation de l'allumage par choc lorsque les paramètres de la phase d'assemblage, sont pris en compte. Les diverses approches analytiques, numériques et expérimentales sont cohérentes entre-elles. / The shock ignition concept in inertial confinement fusion uses an intense power spike at the end of an assembly laser pulse. the key feature of shock ignition are the generation of a high ablation pressure, the shock pressure amplification by at least a factor of a hundred in the cold fuel shell and the shock coupling to the hot-spot. in this theses, new semi-analytical hydrodynamic models are developed to describe the ignitor shock from its generation up to the moment of fuel ignition. A model is developed to describe a spherical concerging shock wave in a pre-heated hotspot. The self-similar solution developed by Guderley is perturbed over the shock Mach number Ms >>1. The first order correction accounts for the effects of the shock strength. An analytical ignition criterion is defined in terms of the shock strength ans th hot-spot areal density. The ignition threshold is higher when the initial Mach number of the shock is lower. A minimal shock pressure of 20 Gbar is needed when it enters the hot-spot. The shock dynamics in the imploding shell is the analyzed. The shock is propagating into a non inertial medium with a high radial pressure gradient and an averall pressure increase with time. The collision with a returning shock coming from the assembly phase enhances further the ignitor shock pressure. The analytica theory allows to des cribe the shock pressure and strength evolution in a typical shock ignition implosion. It is demonstrated that, in the case of the HiPER target design, a generation shock pressure near the ablation zone on the order of 300-400 Mbar is needed. An analysis of experiments on the strong shock generation performed on the OMEGA laser facility is presented. It is sown that a shock presssure close to 300 Mbar near the ablation zone has been reached with an absorbed laser intensity up to 2 x 10(15) W:cm-2 and a laser wavelength of 351 nm. This value is two times higher than the one expected from collisional laser absorption only. That significant pressure enhancement is explained by contribution of hot-electrons generated by non-linear laser/plasma interaction in the corona. The proposed analytical models allow to optimize the shock ignition scheme, including the inuence of the implosion parameters. Analytical, numerical and experimental results are mutualy consistent.
160

Divers aspects des arbres aléatoires : des arbres de fragmentation aux cartes planaires infinies / Various aspects of random trees : from fragmentation trees to infinite planar maps

Stephenson, Robin 27 June 2014 (has links)
Nous nous intéressons à trois problèmes issus du monde des arbres aléatoires discrets et continus. Dans un premier lieu, nous faisons une étude générale des arbres de fragmentation auto-similaires, étendant certains résultats de Haas et Miermont en 2006, notamment en calculant leur dimension de Hausdorff sous des hypothèses malthusiennes. Nous nous intéressons ensuite à une suite particulière d’arbres discrets k-aires, construite de manière récursive avec un algorithme similaire à celui de Rémy de 1985. La taille de l’arbre obtenu à la n-ième étape est de l’ordre de n^(1/k), et après renormalisation, on trouve que la suite converge en probabilité vers un arbre de fragmentation. Nous étudions également des manières de plonger ces arbres les uns dans les autres quand k varie. Dans une dernière partie, nous démontrons la convergence locale en loi d’arbres de Galton-Watson multi-types critiques quand on les conditionne à avoir un grand nombre de sommets d’un certain type fixé. Nous appliquons ensuite ce résultat aux cartes planaires aléatoire pour obtenir la convergence locale en loi de grandes cartes de loi de Boltzmann critique vers une carte planaire infinie. / We study three problems related to discrete and continuous random trees. First, we do a general study of self-similar fragmentation trees, extending some results established by Haas and Miermont in 2006, in particular by computing the Hausdorff dimension of these trees under some Malthusian hypotheses. We then work on a particular sequence of k-ary growing trees, defined recursively with a similar method to Rémy’s algorithm from 1985. We show that the size of the tree obtained at the n-th step if of order n^(1/k), and, after renormalization, we prove that the sequence convergences to a fragmentation tree. We also study embeddings of the limiting trees as k varies. In the last chapter, we show the local convergence in distribution of critical multi-type Galton-Watson trees conditioned to have a large number of vertices of a fixed type. We then apply this result to the world of random planar maps, obtaining that large critical Boltzmann-distributed maps converge locally in distribution to an infinite planar map.

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