Les modèles linéaires généralisés sont une généralisation des modèles de régression linéaire, et sont très utilisés dans le domaine du vivant. Le modèle de régression logistique, l'un des modèles de cette classe, très souvent utilisé dans les études biomédicales demeure le modèle de régression le plus approprié quand il s'agit de modéliser une variable discrète de nature binaire. Dans cette thèse, nous nous intéressons au problème de l'inférence statistique dans le modèle de régression logistique, en présence d'individus immunes dans la population d'étude.Dans un premier temps, nous considérons le problème de l'estimation dans le modèle de régression logistique en présence d'individus immunes, qui entre dans le cadre des modèles de régression à excès de zéros (ou zéro-inflatés). Un individu est dit immune s'il n'est pas exposé à l'événement d'intérêt. Le statut d'immunité est inconnu sauf si l'événement d'intérêt a été observé. Nous développons une méthode d'estimation par maximum de vraisemblance en proposant une modélisation conjointe de l'immunité et des risques d'infection. Nous établissons d'abord l'identifiabilité du modèle proposé. Puis, nous montrons l'existence de l'estimateur du maximum de vraisemblance des paramètres de ce modèle. Nous montrons ensuite,la consistance de cet estimateur, et nous établissons sa normalité asymptotique. Enfin, nous étudions, au moyen de simulations, leur comportement sur des échantillons de taille finie.Dans un deuxième temps, nous nous intéressons à la construction de bandes de confiance simultanées pour la probabilité d'infection, dans le modèle de régression logistique avec fraction immune. Nous proposons trois méthodes de constructions de bandes de confiance pour la fonction de régression. La première méthode (méthodede Scheffé) utilise la propriété de normalité asymptotique de l'estimateur du maximum de vraisemblance, et une approximation par une loi du khi deux pour approcher le quantile nécessaire à la construction des bandes. La deuxième méthode utilise également la propriété de normalité asymptotique de l'estimateur du maximum de vraisemblance et est basée sur une égalité classique de (Landau & Sheep 1970). La troisième méthode (méthode bootstrap) repose sur des simulations, pour estimer le quantile approprié de la loi du supremum d'un processus gaussien. Enfin, nous évaluons, au moyen de simulations, leurs propriétés sur des échantillons de taille finie.Enfin, nous appliquons les résultats de modélisation à des données réelles surla dengue. Il s'agit d'une maladie vectorielle tropicale à transmission strictement inter-humaine. Les résultats montrent que les probabilités d'infection estimées à partir de notre approche de modélisation sont plus élevées que celles obtenues à partir d'un modèle de régression logistique standard qui ne tient pas compte d'une possible immunité. En particulier, les estimations fournies par notre approche suggèrent que le sous-poids constitue un facteur de risque majeur de l'infection par la dengue, indépendamment de l'âge. / Generalized linear models are a generalization of linear regression models, and are widely used in the field of life. The logistic regression model, one of this class of models, widely used in biomedical studies remains the most appropriate regression model when it comes to model discrete variable, binary in nature. In this thesis, we investigate the problem of statistical inference in the logistic regression model, in the presence of immune individuals in the study population.At first, we consider the problem of estimation in the logistic regression model in the presence of immune individuals that enters in the case of zero-inflated regression models. A subject is said to be immune if he cannot experience the outcome of interest. The immune status is unknown unless the event of interest has been observed. We develop a maximum like lihood estimation procedure for this problem, based on the joint modeling of the binary response of interest and the cure status. We investigate the identifiability of the resulting model. Then, we establish the existence, consistency and asymptotic normality of the proposed estimator, and we conduct a simulation study to investigate its finite-sample behavior. In a second time, we focus on the construction of simultaneous confidence bands for the probability of infection in the logistic regression model with immune fraction.We propose three methods of construction of confidence bands for the regression function. The first method (Scheffe's method) uses the asymptotic normality of the maximum like lihood estimator, and an approximation by the chi-squared distribution to approximate the necessary quantile for the construction of bands. The second method uses also the asymptotic normality of the maximum like lihood estimator and is based on a classical equality by (Landau & Sheep 1970). The third method (bootstrap method) is based on simulations, to estimate the appropriate quantile of the law of a supremum of a Gaussian process. Finally, we conduct a simulation study to investigate its finite-sample properties.Finally, we consider a study of dengue fever, which is a tropical mosquito-borneviral human disease, strictly inter-human. The results show that, the estimated probabilities of infection obtained from our approach are larger than the ones derived from a standard analysis that does not take account of the possible immunity. Inparticular, the estimates provided by our approach suggest that underweight constitutes a major risk factor for dengue infection, irrespectively of age.

Syfte och frågeställningar Målet med denna studie var att undersöka hur elever upplever omklädningsrummet och omklädningssituationeni skolan samt vad som påverkar upplevelsen. Syftet med studien var således att problematisera tidigareforskningsresultat kring upplevelsen av omklädningssituationen kopplad till prestation inom ämnet samt attutifrån den förståelse som dessa resultat genererar kunna föreslå åtgärder. Utifrån detta syfte formuleradesforskningsfrågorna “Hur upplever högpresterande respektive lågpresterande elever omklädningssituationen?” samt “Vilka faktorer anser högpresterande respektive lågpresterande elever påverkar situationen?” Teori och metod Studien utfördes i form av en komparativ undersökning med sex respondenter från en gymnasieskola iStockholms innerstad. Dessa var indelade i två elevgrupper utifrån hög/låg närvaro, höga/låga betyg samttidigare idrottsbakgrund. Materialet skapades genom kvalitativa intervjuer av reflexiv och semistruktureradkaraktär, transkriberades sedan med orthographic och analyserades slutligen med inspiration från kvalitativ ochtematisk meningsinnehållsanalys. Det teoretiska ramverket för analysen bottnade i strukturalistisk,poststrukturalistisk och poststrukturalistisk feministisk teoribildning inspirerad av bland annat Pierre Bourdieu, Michel Foucault, Jean-Paul Sartre och Jean Baudrillard. Resultat Gemensamt för eleverna i båda grupperna är att de inte använder skolans duschar och även till viss del undvikerskolans omklädningsrum. Sammanhanget kring både dusch och ombyte upplevs som mer eller mindreobekvämt, onormalt och exponerande. Det sociala sammanhanget, nakenhet i grupp och den egna kroppen iandras ögon ses som centrala faktorer. Även tidsbrist, schemaläggning och behovet att ta med sig en handdukmenas påverka. De två elevgruppernas upplevelser verkar enbart skilja sig i viss mån från varandra. Dehögpresterande eleverna ser skolämnet som något positivt, ser det fysiska rummet som bristfälligt och önskarförändringar i schemat i högre grad. De lågpresterande eleverna verkar i högre grad se handduken som ett problem. Slutsatser Den vanligaste orsaken till att undvika dusch eller ombyte verkar handla om vad som anses normalt, snarare änupplevt obehag på grund av nakenhet. De elever som har större erfarenhet av idrottsverksamhet utanför skolanverkar dock vara mer bekväma med både ombyte och nakenhet i grupp, något som förklaras genom habitus ochsymboliskt kapital. Nakenhet och exponering är dock centrala faktorer för vissa elever. Upplevelsen av att kroppen som både objekt och subjekt inte lever upp till de förväntade kraven skapar tillsammans med en upplevelse av övervakning och dömande blickar ett beläggande av skuld- och skam på sig själv. Ett samband mellan hög frånvaro, låga betyg, en negativ inställning till ämnet och obehag kopplat till omklädningsrummet motsägs delvis av denna studie. Det är snarare upplevelsen av normalitet i sammanhanget som påverkar valet attanvända dusch- och omklädningsrum eller inte, oavsett närvaro, betyg eller inställning. / Aim and research questions The aim of this study was to investigate how students experience their school’s changing room and whatinfluences this experience. The purpose of the study was thus to problematize previous research results regarding the experience of the changing situation linked to performance within the school subject and to beable to propose measures based on the understanding these results generate. Based on this aim, the following research questions were formulated: "How do high-achieving and low-achieving students experience the changing situation?" and "Which factors do high-achieving and low-achieving students think influence thesituation?". Theory and method The study was carried out in the form of a comparative survey with six respondents from an upper secondaryschool in inner city Stockholm. These were divided into two student groups based on high/low attendance,high/low grades and previous sports background. The material was created through qualitative interviews of areflexive and semi-structured nature, then transcribed using orthographic and finally analyzed with inspirationfrom qualitative and thematic content analysis. The theoretical framework for the analysis was rooted instructuralist, poststructuralist and poststructuralist feminist theorizing inspired by, among others, Pierre Bourdieu, Michel Foucault, Jean-Paul Sartre and Jean Baudrillard. Results Common to the students in both groups is that they do not use the school's showers and also to some extentavoid the school's changing rooms. The context surrounding both showering and changing is experienced asmore or less uncomfortable, abnormal and exposing. The social context, group nudity and one's own body in theeyes of others are seen as central factors. Lack of time, scheduling and the need to bring a towel are also said tohave an effect. The experiences of the two student groups only seem to differ from each other to a certain extent. The high-achieving students see the school subject as something positive, see the physical space as deficient anddesire changes in the schedule to a greater degree. The low-achieving students seem to see the towel as aproblem to a greater extent. Conclusions The most common reason for avoiding showering or changing appears to be about what is considered normal, rather than perceived discomfort due to nudity. However, the students who have more experience of sportsactivities outside school seem to be more comfortable with both changing and nudity in a group, something thatis explained by habitus and symbolic capital. However, nudity and exposure are central factors for somestudents. The experience that the body as both object and subject does not live up to the expected requirements,together with an experience of surveillance and judgmental looks, creates a coating of guilt and shame ononeself. An association between high absenteeism, low grades, a negative attitude towards the school subjectand discomfort linked to the changing room is partially contradicted by this study. Rather, it is the experience ofnormality in the context that influences the choice to use the shower and changing rooms or not, regardless of attendance, grade or attitude.

This study looks at how autism is represented by characters in popular film, by analyzing the protagonists of two films, I rymden finns inga känslor and Please Stand By, with narrative and character analysis and then interpreting the result against social constructionism and theories of normality. The analysis results in the emergence of stereotypical characters in both films, and a statement that this can help to form a kind of symbol for what autism means for non-autistic individuals. The discussion states that in order to combat stereotypical representation in popular media, a change is needed from a medical model to a social model together with a change in the discourse around what autism means for autistic individuals.

Quantifier et mesurer le risque dans un environnement partiellement ou totalement incertain est probablement l'un des enjeux majeurs de la recherche appliquée en mathématiques financières. Cela concerne l'économie, la finance, mais d'autres domaines comme la santé via les assurances par exemple. L'une des difficultés fondamentales de ce processus de gestion des risques est de modéliser les actifs sous-jacents, puis d'approcher le risque à partir des observations ou des simulations. Comme dans ce domaine, l'aléa ou l'incertitude joue un rôle fondamental dans l'évolution des actifs, le recours aux processus stochastiques et aux méthodes statistiques devient crucial. Dans la pratique l'approche paramétrique est largement utilisée. Elle consiste à choisir le modèle dans une famille paramétrique, de quantifier le risque en fonction des paramètres, et d'estimer le risque en remplaçant les paramètres par leurs estimations. Cette approche présente un risque majeur, celui de mal spécifier le modèle, et donc de sous-estimer ou sur-estimer le risque. Partant de ce constat et dans une perspective de minimiser le risque de modèle, nous avons choisi d'aborder la question de la quantification du risque avec une approche non-paramétrique qui s'applique à des modèles aussi généraux que possible. Nous nous sommes concentrés sur deux mesures de risque largement utilisées dans la pratique et qui sont parfois imposées par les réglementations nationales ou internationales. Il s'agit de la Value at Risk (VaR) qui quantifie le niveau de perte maximum avec un niveau de confiance élevé (95% ou 99%). La seconde mesure est l'Expected Shortfall (ES) qui nous renseigne sur la perte moyenne au delà de la VaR. / To quantify and measure the risk in an environment partially or completely uncertain is probably one of the major issues of the applied research in financial mathematics. That relates to the economy, finance, but many other fields like health via the insurances for example. One of the fundamental difficulties of this process of management of risks is to model the under lying credits, then approach the risk from observations or simulations. As in this field, the risk or uncertainty plays a fundamental role in the evolution of the credits; the recourse to the stochastic processes and with the statistical methods becomes crucial. In practice the parametric approach is largely used.It consists in choosing the model in a parametric family, to quantify the risk according to the parameters, and to estimate its risk by replacing the parameters by their estimates. This approach presents a main risk, that badly to specify the model, and thus to underestimate or over-estimate the risk. Based within and with a view to minimizing the risk model, we choose to tackle the question of the quantification of the risk with a nonparametric approach which applies to models as general as possible. We concentrate to two measures of risk largely used in practice and which are sometimes imposed by the national or international regulations. They are the Value at Risk (VaR) which quantifies the maximum level of loss with a high degree of confidence (95% or 99%). The second measure is the Expected Shortfall (ES) which informs about the average loss beyond the VaR.

Dans cette thèse, nous étudions des modèles de moyennes conditionnelles de séries temporelles à valeurs entières. Tout d’abord, nous proposons l’estimateur de quasi maximum de vraisemblance de Poisson (EQMVP) pour les paramètres de la moyenne conditionnelle. Nous montrons que, sous des conditions générales de régularité, cet estimateur est consistant et asymptotiquement normal pour une grande classe de modèles. Étant donné que les paramètres de la moyenne conditionnelle de certains modèles sont positivement contraints, comme par exemple dans les modèles INAR (INteger-valued AutoRegressive) et les modèles INGARCH (INteger-valued Generalized AutoRegressive Conditional Heteroscedastic), nous étudions la distribution asymptotique de l’EQMVP lorsque le paramètre est sur le bord de l’espace des paramètres. En tenant compte de cette dernière situation, nous déduisons deux versions modifiées du test de Wald pour la significativité des paramètres et pour la moyenne conditionnelle constante. Par la suite, nous accordons une attention particulière au problème de validation des modèles des séries temporelles à valeurs entières en proposant un test portmanteau pour l’adéquation de l’ajustement. Nous dérivons la distribution jointe de l’EQMVP et des autocovariances résiduelles empiriques. Puis, nous déduisons la distribution asymptotique des autocovariances résiduelles estimées, et aussi la statistique du test. Enfin, nous proposons l’EQMVP pour estimer équation-par-équation (EpE) les paramètres de la moyenne conditionnelle des séries temporelles multivariées à valeurs entières. Nous présentons les hypothèses de régularité sous lesquelles l’EQMVP-EpE est consistant et asymptotiquement normal, et appliquons les résultats obtenus à plusieurs modèles des séries temporelles multivariées à valeurs entières. / The framework of this PhD dissertation is the conditional mean count time seriesmodels. We propose the Poisson quasi-maximum likelihood estimator (PQMLE) for the conditional mean parameters. We show that, under quite general regularityconditions, this estimator is consistent and asymptotically normal for a wide classeof count time series models. Since the conditional mean parameters of some modelsare positively constrained, as, for example, in the integer-valued autoregressive (INAR) and in the integer-valued generalized autoregressive conditional heteroscedasticity (INGARCH), we study the asymptotic distribution of this estimator when the parameter lies at the boundary of the parameter space. We deduce a Waldtype test for the significance of the parameters and another Wald-type test for the constance of the conditional mean. Subsequently, we propose a robust and general goodness-of-fit test for the count time series models. We derive the joint distribution of the PQMLE and of the empirical residual autocovariances. Then, we deduce the asymptotic distribution of the estimated residual autocovariances and also of a portmanteau test. Finally, we propose the PQMLE for estimating, equation-by-equation (EbE), the conditional mean parameters of a multivariate time series of counts. By using slightly different assumptions from those given for PQMLE, we show the consistency and the asymptotic normality of this estimator for a considerable variety of multivariate count time series models.

The main purpose of the dissertation is to understand meaning-making practices used by people suffering from acquired brain damage with severe physical and communicative disabilities, in order to create and sustain their identity and personhood in relation to other people. The study emanates from the idea that identity and personhood, also in relation to disability, are created/sustained in ongoing interaction between people in everyday situations, and that the ability to narrate is central to such a creation of identity. Therefore, it is of particular interest to try to understand what communicative and storytelling abilities/possibilities people with severe acquired brain damage have in presenting their identity. The study is ethnographic and based upon a year-long field study of participant observations at a day centre for people with acquired brain damage. Gathered data consist of written field notes, informal interviews conducted with both participants and personnel and approximately 70 hours of video data. The study shows how an identity as ‘severely disabled’ is created in the co-created storytelling between participants and personnel and that this identity seems to mean that one is dependent upon others to get along in everyday life at least if one listens only to spoken stories. Yet the study also shows that there exist different opinions about what this identity as ‘severely disabled’ could mean that there is a wish among the participants to be able to present a desirable identity as “normal”, and that such an identity comes to mean to be independent and self-determined. Normality, however, must be understood in relation to surrounding society (and the grand cultural narratives that surround us). Thus the study shows that normality in relation to severe disabilities is almost impossible to achieve because normality in relation to illness/disease/body contains the hope of a cure or an improvement. The participants in this study, however, have all been labelled as incurable – there is no hope of such a cure or improvement. That, on the other hand, does not mean that the participants do not try to tell such stories anyway in their quest to achieve this desirable identity. However, in order to hear this story we need to listen to stories that usually remain untold. A palpable hierarchy between different modes of language use was identified, where verbal/spoken language is supreme, resulting in the disabled participants not being perceived as competent interactors/communicators due to their difficulties in using verbal communication. Hence their ways of creating/telling stories, through embodiment and enactment, are not recognised as valid ways to create/tell stories; this is discussed in relation to both practical implications for health care settings as well as for further narrative research. / Avhandlingens huvudsyfte är att förstå meningsskapande praktiker som personer som drabbats av förvärvad hjärnskada med grava såväl fysiska som kommunikativa funktionshinder använder för att skapa och upprätthålla sin identitet och sitt personskap i relation till andra människor. Studien utgår ifrån att identitet och personskap, också i relation till funktionshinder, är något som skapas och upprätthålls i det pågående samspelet mellan människor i vardagliga situationer och att förmågan att berätta är central för detta identitetsskapande. Därför är det av särskilt intresse att försöka förstå vilka möjligheter personer med grava förvärvade hjärnskador har när det gäller att kommunicera och använda berättandet som ett sätt att presentera sin identitet. Studien är etnografisk och baseras på ett årslångt fältarbete bestående av deltagande observationer på ett dagcenter för människor med förvärvade hjärnskador. Insamlade data består av fältanteckningar, informella intervjuer med både deltagare och personal och ca 70 timmar videomaterial. Studien visar hur en identitet som ’gravt funktionshindrad’ skapas i det gemensamma berättandet mellan deltagare och personal och att denna identitet verkar innebära att man är beroende av andra för att klara sitt vardagliga liv, åtminstone om man enbart lyssnar till talade berättelser. Likväl visar studien även att det kan råda delade meningar om vad denna identitet som ’gravt funktionshindrad’ kan innebära och att det bland deltagarna finns en strävan att kunna presentera en önskvärd identitet som ”normal” och att en sådan identitet innebär att vara oberoende och självbestämmande. Normalitet måste dock förstås i relation till omgivande samhälle (och de stora, kulturella berättelser som omger oss) och studien visar att normalitet i samband med grava funktionshinder är i det närmaste omöjligt att uppnå då normalitet i relation till sjukdom/kropp innefattar ett hopp om att bli frisk, eller åtminstone bättre. Deltagarna i denna studie har emellertid diagnostiserats som obotliga – det finns inget hopp om förbättring. Detta innebär inte desto mindre att deltagarna ändå försöker berätta sådana berättelser i strävan efter att uppnå en önskvärd identitet. Dock; för att höra denna berättelse krävs ett lyssnande på berättelser som vanligtvis förblir oberättade. En tydlig hierarki mellan olika former av språkanvändning identifieras, där det talade ordet och den talade berättelsen ses som överlägsen. Detta får till konsekvens att de funktionshindrade inte ses som kompetenta aktörer/kommunikatörer pga. av sina svårigheter att kommunicera verbalt och att deras sätt att skapa berättelser, genom förkroppsligande framställningar, inte erkänns som legitima sätt att berätta. Detta diskuteras både i relation till olika praktiska implikationer för vårdinstitutioner och för vidare narrativ forskning.

This thesis deals with questions concerning ongoing constructions of heterosexuality as a norm in the Swedish church. Empirically the study is based partly on interviews with thirteen homo- and bisexual priests, one district visitor and one church politician and partly on some of the church’s own inquiries and documents concerning the question of Christianity and ”deviant” sexuality. The aim for this study is to examine how norms for sexuality, coexistence and gender are repeated in the documents created by the Swedish church itself about homosexuality and Christianity and to discern how these norms are present and have sense – are reproduced, challenged and transformed in life stories of Christian homo- and bisexual individuals. To be able to see how the notion of homosexuality as abnormal is reproduced, secured and challenged I have chosen to interpret texts, observations and life stories from a critical discourse perspective. In this theoretical tradition it is central to stress how, or rather to investigate what strategies are used to produce and maintain notions of ”abnormality”. One dominating view in the discussions within the church is that homosexuals and heterosexuals have equal value but that partnership cannot be equated with marriage. This understanding is expressed in my examples of formations of heteronormativity within the church. In the interview persons’ narratives there are discourses represented that are articulated in the church’s own inquiries but the narratives also express counter discourses. They speak about themselves in relation to, for example, imperative heterosexuality, homosexual ideals, core family ideals, theological way of thinking and dichotomizing understanding of gender. I have identified several ”uses” in the narratives and all of them are contained in an overall Christian homosexual ”us”. Instead of viewing themselves as being ”wrong” some of the interview persons have moved the problem to the heteronormativity. Experiences of not being part of the norm have made them strong and willing to struggle and fight for their rights. This position, outside the norm, is by some viewed positively. The homosexuals’ experiences of oppression have led to a desire to liberate the church from homophobia and show ”the true” church, where no one is discriminated. Homosexuals are accepted within the church, but only as deviants. This way heterosexuality is being made the superior category. Its meaning and superior position cannot be questioned according to many of the church’s representatives. Still, this is exactly what is happening when homosexuals are increasingly visible to the public and when they challenge the heterosexual norm. This provocation makes the heterosexual norm visible and forces representatives of the norm to deal with it! / Författaren har bytt efternamn till Holst.

Arbetet i särskolan ska förbereda för vuxenlivet, och sex- och samlevnadsundervisningen ska bedrivas utifrån ett främjande perspektiv med fokus på sexualitet, identitet, normer och jämställdhet. I Skolinspektionens aktuella granskning av sex- och samlevnadsundervisningen framkommer betydande brister. Den här studien vill öka kunskapen om pedagogers föreställningar om sexualitet och sex- och samlevnad avseende elever med intellektuell funktionsnedsättning i särskolan. Undersökningen utgörs av semistrukturerade intervjuer med pedagoger i gymnasiesärskolan. Utifrån ett normkritiskt perspektiv har insamlad empiri analyserats med hjälp av begreppen cripteori, normalitet och empowerment i syfte att beskriva och tolka hur pedagogerna i särskolan förhåller sig till eleverna och deras förmåga och rätt till sin sexualitet. Olika teman har konstruerats ur empirin för att definiera attityder, normer och förhållningssätt. Resultatet visar pedagoger med oerhört engagemang i ett svårt ämne där de känner sig ensamma och utsatta utan pedagogiskt stöd. Eleverna visar en stor önskan att passa in, de skäms för att gå i särskolan och gör allt för att inte framstå som avvikande. Osäkerheten hos pedagogerna är av central betydelse samtidigt som den normkritiska medvetenheten i undervisningen behöver stärkas. Slutsatsen är att kompetensutveckling och pedagogisk vägledning inom särskolan är avgörande för detta viktiga men känsliga ämne. / The work in school for students with special needs should prepare for adult life, and sex and cohabitation education should be based on a promotion perspective with focus on sexuality, identity, norms and gender equality. The School Inspectorate's current review of sex and cohabitation education reveals significant shortcomings. This study aims to increase knowledge about educators' perceptions of sexuality, and sex and cohabitation, regarding students with intellectual disabilities. The study consists of semistructured interviews with educators in special needs upper secondary school. Based on a norm critical perspective, collected data has been analyzed using the concepts of crip theory, normality and empowerment for the purpose of describing and interpreting how the educators relate to the students, their ability and right to their own sexuality. Different themes have been constructed from the collected data in order to define attitudes, norms and approaches. The result shows educators with huge commitment in a difficult field where they feel lonely and vulnerable without pedagogical support. The students show great desire to fit in, they are ashamed of going to special school and do anything to not appear deviant. The insecurity within the educators is of central importance and there is little norm critical awareness in the teaching. The conclusion is that knowledge development and pedagogical guidance within the special needs upper secondary school is crucial in this important but sensitive field.

Cette thèse vise à modéliser les instabilités hydrodynamiques générant des détachements tourbillonnaires pariétaux (ou VSP) responsables des Oscillations De Pression dans les moteurs à propergol solide longs et segmentés par interaction avec l’acoustique du moteur. Ces instabilités sont modélisées en tant que modes de stabilité linéaire globaux de l’écoulement d’un conduit à parois débitantes. En supposant que les structures pariétales émergent d’une perturbation de l’écoulement de base, des modes discrets et indépendants du maillage utilisé sont calculés. Dans ce but, une discrétisation par collocation spectrale multi-domaine est implémentée dans un solveur parallèle afin de s’affranchir de la croissance polynomiale des fonctions propres et de la présence de couches limites. Les valeurs propres ainsi calculées dépendent explicitement des frontières du domaine, à savoir la position de la perturbation et celle de la sortie, et sont ensuite validées par simulation numérique directe. On montre alors qu’elles permettent bien de décrire la réponse à une perturbation initiale de l’écoulement modifié par une rupture de débit pariétale. Ensuite, la simulation d’une réponse forcée par l’acoustique se fait sous forme de structures tourbillonnaires dont les fréquences discrètes sont en accord avec celles des modes de stabilité. Ces structures sont réfléchies en ondes de pression de même fréquences remontant l’écoulement. Finalement, la simulation numérique et la théorie de la stabilité permettent de montrer que le VSP, dont la réponse est linéaire vis-à-vis d’un forçage compressible comme l’acoustique, est le phénomène moteur des Oscillations De Pression. / The current work deals with the modeling of the hydrodynamic instabilities that play a major role in the triggering of the Pressure Oscillations occurring in large segmented solid rocket motors. These instabilities are responsible for the emergence of Parietal Vortex Shedding (PVS) and they interact with the boosters acoustics. They are first modeled as eigenmodes of the internal steady flowfield of a cylindrical duct with sidewall injection within the global linear stability theory framework. Assuming that the related parietal structures emerge from a baseflow disturbance, discrete meshindependant eigenmodes are computed. In this purpose, a multi-domain spectral collocation technique is implemented in a parallel solver to tackle numerical issues such as the eigenfunctions polynomial axial amplification and the existence of boundary layers. The resulting eigenvalues explicitly depend on the location of the boundaries, namely those of the baseflow disturbance and the duct exit, and are then validated by performing Direct Numerical Simulations. First, they successfully describe flow response to an initial disturbance with sidewall velocity injection break. Then, the simulated forced response to acoustics consists in vortical structures wihich discrete frequencies that are in good agreement with those of the eigenmodes. These structures are reflected into upstream pressure waves with identical frequencies. Finally, the PVS, which response to a compressible forcing such as the acoustic one is linear, is understood as the driving phenomenon of the Pressure Oscillations thanks to both numerical simulation and stability theory.

Le problème d'intérêt est d'estimer la fonction de concentration et l'aire sous la courbe (AUC) à travers l'estimation des paramètres d'un modèle de régression linéaire avec un processus d'erreur autocorrélé. On construit un estimateur linéaire sans biais simple de la courbe de concentration et de l'AUC. On montre que cet estimateur construit à partir d'un plan d'échantillonnage régulier approprié est asymptotiquement optimal dans le sens où il a exactement la même performance asymptotique que le meilleur estimateur linéaire sans biais (BLUE). De plus, on montre que le plan d'échantillonnage optimal est robuste par rapport à la misspecification de la fonction d'autocovariance suivant le critère du minimax. Lorsque des observations répétées sont disponibles, cet estimateur est consistant et a une distribution asymptotique normale. Les résultats obtenus sont généralisés au processus d'erreur de Hölder d'indice compris entre 0 et 2. Enfin, pour des tailles d'échantillonnage petites, un algorithme de recuit simulé est appliqué à un modèle pharmacocinétique avec des erreurs corrélées. / The problem of interest is to estimate the concentration curve and the area under the curve (AUC) by estimating the parameters of a linear regression model with autocorrelated error process. We construct a simple linear unbiased estimator of the concentration curve and the AUC. We show that this estimator constructed from a sampling design generated by an appropriate density is asymptotically optimal in the sense that it has exactly the same asymptotic performance as the best linear unbiased estimator (BLUE). Moreover, we prove that the optimal design is robust with respect to a misspecification of the autocovariance function according to a minimax criterion. When repeated observations are available, this estimator is consistent and has an asymptotic normal distribution. All those results are extended to the error process of Hölder with index including between 0 and 2. Finally, for small sample sizes, a simulated annealing algorithm is applied to a pharmacokinetic model with correlated errors.