Bakgrund: Antalet planerade hemförlossningar i Sverige ligger idag på runt 100 per år. Kvinnor som har genomgått en hemförlossning upplever starka känslor av autonomi och tillit till sina kroppar och sin förmåga att föda barn. Fler önskar själva välja födelseplats samt vara delaktiga i sin vård och planering därav och i de beslut som tas under en förlossning. Motiv: Jag önskar med detta examensarbete undersöka varför kvinnor väljer att föda hemma och hur den förlossningen har upplevts i jämförelse med tidigare förlossningar på sjukhus. Vilka tidigare erfarenheter har bidragit till att kvinnor väljer att föda hemma? Hur kommer det sig att kvinnor väljer att betala för sin hemförlossning? Syfte: Syftet med detta examensarbete var att undersöka kvinnors motiv till och erfarenheter av att föda i hemmet. Metod: Semistrukturerade intervjuer genomfördes med sex kvinnor runtom i Sverige. Intervjuerna analyserades med kvalitativ innehållsanalys. Resultat: I analysen framkom tre huvudkategorier och tio subkategorier. Huvudkategorierna var: Att välja hemförlossning på grund av negativa upplevelser i samband med sjukhusförlossning, att föda på egna villkor och att uppleva kontinuerligt stöd och närvaro av barnmorskor. Konklusion: Motiv som självbestämmande, en tryggare förlossning med barnmorskor som ger personcentrerad vård fick kvinnorna att välja hemförlossning fortsättningsvis. Förlossningsvården bör eftersträva en mer inkluderande och säker vård, där även valfri förlossningsmiljö kan erbjudas. Det kan medföra att fler kvinnor känner sig trygga var de än föder, samt ha valmöjligheten att föda hemma med professionellt stöd oavsett var de är bosatta och oberoende av socioekonomiska faktorer. En god förlossningsupplevelse med färre medicinska insatser, minskade obstetriska skador och en trygg miljö kan motverka negativa känslor kopplat till förlossning, skapa välbefinnande och stärka empowerment. / Background: The number of planned home births in Sweden today is around 100 per year. Studies show that women who have had a home birth, experience strong feelings of autonomy and confidence in their bodies and ability to give birth. More people want to choose their own place of birth and be involved in their care, planning and the decisions that are made during a birth. Motive: With this thesis, I want to investigate why women choose to give birth at home and how that birth has been experienced in comparison with previous births in hospitals. What previous experiences have contributed to women choosing to give birth at home? How come women choose to pay for their home birth? Aim: The purpose of this study was to investigate women's motives for and experiences of giving birth at home.Methods: Semi-structured interviews were conducted with six women. The interviews were analyzed with qualitative content analysis. Result: Three main categories and ten subcategories emerged. The main categories are: To choose home birth due to negative experiences in connection with hospital birth, to give birth on one's own terms and to experience continuous support and presence of midwifes. Conclusion: Motives such as self-determination, a safer childbirth with midwives that provide person-centered care made women choose homebirth in the future. Maternity care should strive for more inclusive and safe care, where an optional delivery environment can also be offered. This can mean that more women feel secure wherever they give birth and have the choice to give birth at home with professional support regardless of where they live and regardless of socio-economic factors. A good delivery experience with fewer medical interventions, reduced obstetric injuries and a safe environment can counteract negative emotions linked to childbirth, create well-being, strengthen empowerment.

[ES] A pesar de la importancia de las turbinas radiales de doble entrada y doble voluta en el flujo para motores turboalimentados, sus mapas característicos y su modelado totalmente predictivo utilizando códigos dinámicos de gas 1D aún no están bien establecidos. La complejidad del flujo no estacionario y la admisión desigual de estas turbinas, cuando funcionan con pulsos de gases de escape del motor, las convierte en un sistema desafiante. Principalmente debido a la admisión de flujo desigual, se introduce un grado adicional de libertad con respecto a las turbinas conocidas como de una sola entrada con o sin álabes en el estator. Además, la adición de la segunda entrada a la voluta de la turbina aporta una complejidad adicional para determinar los parámetros de rendimiento de la turbina en estacionario estable y en condiciones de admisión desiguales.Esta tesis tiene como novedad principal un procedimiento simple para caracterizar experimentalmente y elaborar mapas característicos de estas turbinas con condiciones de flujo desiguales. Este método de análisis permite interpolar fácilmente dentro de los mapas distintivos propuestos o ajustar modelos simples y convincentes para calcular y extrapolar parámetros de rendimiento completo de turbinas de doble entrada y doble voluta. También hemos descrito aquí, dos modelos innovadores de línea media 0D que requieren una cantidad mínima de datos experimentales para calibrar ambos: es decir, el modelo de parámetros de flujo másico y el modelo de eficiencia isentrópica. Ambos modelos son predictivos en condiciones de admisión de flujo parcial o desigual utilizando como entradas: la relación de flujo másico entre ramas; la relación de temperatura total entre ramas; la relación de velocidad de álabe a chorro en cada rama y la relación de presión en cada rama. Estas cinco entradas generalmente son proporcionadas instantáneamente por códigos de dinámica de gas 1D. Por lo tanto, la novedad del modelo es su capacidad de ser utilizado de manera casi constante para la predicción del rendimiento de las turbinas de doble entrada y de doble voluta. Esto se puede lograr instantáneamente ya que las turbinas se calculan en condiciones de flujo pulsante y desigual en motores turbo alimentados. Además, se muestra una metodología para caracterizar el coeficiente de descarga de una válvula de alivio de presión. Para estimar el flujo de gas por la válvula de alivio en modelos unidimensionales, se correlaciona y valida un modelo empírico. Finalmente, se ha elaborado un mapa óptimo del coeficiente de descarga a través del método de interpolación, que puede integrarse en el sistema de modelo de motor turboalimentado completo unidimensional, para calcular el flujo másico real a través de la válvula de descarga y las válvulas de conexión de desplazamiento. Finalmente, los modelos han sido completamente validados al acoplarlos con un software de modelado unidimensional que simula tanto el banco de gas como el motor completo. Por un lado, los resultados de las validaciones del banco de gas muestran que el modelo puede predecir bien todas las variables de flujo estacionario. Por otro lado, los resultados de la validación de todo el motor muestran que el modelo es capaz de producir todas las variables del motor a plena carga como el flujo de masa de aire y el par de frenado con un buen grado de acuerdo con los datos experimentales. / [EN] Despite the importance of radial in-flow twin-entry and dual-volute turbines for turbocharged engines, their characteristic maps and fully predictive modelling using 1D gas dynamic codes are not well established yet. The complexity of the un-steady flow and the unequal admission of these turbines, when operating with pulses of engine exhaust gas, make them a challenging system. Mainly due to the unequal flow admission, an additional degree of freedom is introduced to well-known single entry vanned or vaneless turbines. Moreover, the addition of the second inlet to the turbine volute brings extra complexity in determining the steady-state turbine performance parameters under unequal admission conditions. This thesis has a main novelty, which is a simple procedure for characterizing experimentally and elaborating characteristic maps of these turbines with unequal flow conditions. This method of analysis allows easy interpolating within the proposed distinctive maps or simple convincing models for calculating and extrapolating full performance parameters of twin-entry and dual-volute turbines. Here are also described two innovative 0D mean-line models that require a minimum quantity of experimental data for calibrating both: i.e. the mass flow parameter model and the isentropic efficiency model. Both models are predictive either in partial or unequal flow admission conditions using as inputs: the mass flow ratio and the total temperature ratio between the branches; the blade speed ratio and expansion ratio in each branch. These six inputs are generally instantaneously provided by 1D gas-dynamics codes.} Therefore, the novelty of the model is its ability to be used in a quasi-steady way for twin and dual-volute turbines performance prediction. This can be achieved instantaneously as turbines are calculated under pulsating and uneven flow conditions at turbocharged engines. Furthermore, a methodology for characterizing the discharge coefficient of a wastegate and scroll connection valve in a gas stand is shown. For estimating the gas flow over the same in one-dimensional models, an empirical model is correlated and validated. Finally, an optimal map of discharge coefficient has been drawn out through the interpolation method. This map can be integrated into the full one-dimensional turbocharged engine model system, in order to calculate the actual mass flow through the wastegate and scroll connection valves. Finally, the models have been fully validated by coupling them with one-dimensional modelling software and simulated both the gas stand and the whole engine measured points. On the one hand, the validation results from the gas stand simulation show that the model can predict well all steady flow variables. On the other hand, the validation results from the whole engine simulation show that the model is able to produce all the full load engine variables like air mass flow and brake torque in a reasonable degree of agreement with the experimental data. / [CA] Malgrat la importància de les turbines radials amb doble entrada i de doble voluta per als motors turboalimentats, els seus mapes característics i el seu model completament predictiu mitjançant codis dinàmics de gas 1D encara no estan ben establerts. La complexitat del flux constant i l'admissió desigual d'aquestes turbines, quan funcionen amb polsos de gas d'escapament del motor, les converteixen en un sistema difícil. Principalment a causa de la admissió de flux desigual, s'introdueix un grau addicional de llibertat a les conegudes turbines vendes o d'entrada d'una sola entrada. A més, l'addició de la segona entrada a la voluta de la turbina aporta una complexitat addicional per determinar els paràmetres de rendiment de la turbina en estat estacionari en condicions d'admissió desigual. Aquesta tesi té com a novetat principal un procediment senzill per caracteritzar experimentalment i elaborar mapes característics d'aquestes turbines amb condicions de cabal desigual. Aquest mètode d'anàlisi permet interpolar fàcilment dins dels mapes distintius proposats o models senzills convincents per calcular i extrapolar paràmetres de rendiment complet de les turbines d'entrada doble i de doble voluta. Aquí també hem descrit dos models innovadors de línia mitjana 0D que requereixen una quantitat mínima de dades experimentals per calibrar tots dos: és a dir, el model de paràmetre de flux massiu i el model d'eficiència isentròpica. Els dos models són predictius en condicions d'admissió de flux parcial o desigual utilitzant com a entrada: la proporció de flux entre les branques; la relació total de la temperatura entre les branques; la relació velocitat fulla-raig a cada branca i la proporció de pressió a cada branca. Aquests cinc inputs generalment es proporcionen de manera instantània mitjançant codis de dinàmica de gas 1D. Per tant, la novetat del model és la seva capacitat d'utilitzar-se d'una manera quasi constant per a la predicció del rendiment de les turbines bessones i de doble voluta. Es pot aconseguir de forma instantània, ja que les turbines es calculen en condicions de flux pulsatòries i desiguals en motors turboalimentats. A més, es mostra una metodologia per a caracteritzar el coeficient de descàrrega d'una vàlvula de connexió per canals i desplaçaments en un suport de gas. Per estimar el flux de gas sobre el mateix en models unidimensionals, es correlaciona i valida un model empíric. Finalment, s'ha elaborat un mapa òptim de coeficient de descàrrega mitjançant el mètode d'interpolació, que pot integrar-se al sistema de model turboalimentat complet del motor turbo, per calcular el cabal de massa real a través de les vàlvules de connexió de desguàs i desplaçament. Finalment, els models s'han validat completament combinant-los amb un programari de modelatge unidimensional que simula tant el suport de gas com el motor sencer. D'una banda, els resultats de les validacions de l'estand de gas demostren que el model és capaç de predir bé totes les variables de flux constant. D'altra banda, els resultats de validació del motor complet demostren que el model és capaç de produir totes les variables del motor de càrrega completa, com ara el flux de massa d'aire i el pare de fre d'una bona manera amb les dades experimentals. / Samala, V. (2020). Experimental characterization and mean line modelling of twin-entry and dual-volute turbines working under different admission conditions with steady flow [Tesis doctoral]. Universitat Politècnica de València. https://doi.org/10.4995/Thesis/10251/153475

Ce mémoire a étudié les perceptions de femmes haïtiennes vivant au Québec depuis moins de cinq ans de leurs relations sexuelles avec les hommes et de leurs rapports de couple. Après avoir opté pour une méthodologie de recherche qualitative, la théorie féministe intersectionnelle a été retenue comme cadre d’analyse. Des entretiens individuels semi-dirigés ont été menés auprès de 9 femmes haïtiennes, âgées de 18 à 60 ans et ayant immigré au Québec depuis moins de cinq ans. Les perceptions des femmes de la sexualité ont été appréhendées comme étant un ensemble de discours et de pratiques inter reliés, qui se construit dès l’enfance, et qui reproduit les types de rapports inégalitaires entre hommes et femmes qui existent dans la société haïtienne et dans leur couple. Ces rapports inégalitaires sont véhiculés entre les générations à travers la plupart des institutions sociales comme la famille, l’école, la culture, la législation. Ce processus de construction des perceptions de la sexualité est également influencé par des enjeux socio-économiques et de pouvoir. Les résultats de cette recherche permettent de disposer de données scientifiques sur la sexualité des femmes et les rapports de couple en Haïti et l’influence du processus migratoire. Ces résultats soulignent également la nécessité pour le travail social haïtien d’encourager le développement de l’empowerment économique des femmes et leur participation aux débats actuels de la société sur l’évolution de la condition féminine. / The purpose of this research was to explore the perceptions of Haitian women that had immigrated to Quebec in the past five years, of their sexual relationships with men and the extent to which it is reflected in the different types of conjugal relationships. After choosing a qualitative research method, the intersectional feminist theory has been adopted for the analysis. Individual semi-structured interviews were conducted with 9 Haitian women, aged 18 and 60 years and having immigrated to Quebec in the past five years. The women’s perceptions of sexual relationships have been reported as being a set of practices and discourses interrelated built since childhood and reproducing the unequal relationships between men and women that exist in the Haitian society and in the couples. These unequal relationships are transmitted through the generations and through most of the social institutions such as family, school, culture, laws. This process is also influenced by socio-economic and power issues. The results of this research give scientific data on women sexuality and couple relationships as well as the influence of immigration process. These results also emphasize the need for the Haitian social work to encourage the development of economic empowerment of women and their participation in current debates in society on the development of women. / Memwa sa a vle etidye ki pèsepsyon fanm ayisyèn yo genyen de rapò seksyel yo ak gason, e nan ki mezi pèsepsyon sa yo repwodwi kalite relasyon ki egziste ant yomenm ak nèg yo. Rechèch la chwazi yon metodoloji kalitativ, apresa li kenbe teyori feminis entèseksyonèl kom kad ki pou pemet li analize done li yo. Rechèch la nenen 9 antrevi mwatye ouvè, mwatye fèmen ak 9 fanm ayisyèn, ki genyen ant 18 ak 60 lane, epi ki imigre nan pwovens kebèk, nan peyi Kanada depi mwens pase 5 lane. Dapre rezilta rechèch la, pèsepsyon medanm yo genyen de seksyalite yo tradwi pa yon pakèt pawòl ak yon pakèt abitid ki mare ansanm. Medanm yo komanse ranmase bagay sayo depilè yo te timoun lakay paran yo pou jiskaske yo vin granmoun lakay pa yo. Fason sa yo medanm yo konprann seksyalite a tou, se yon bagay ki soti nan relasyon fòskote ki egziste ant fanm ak gason, ni nan sosyete ayisyènn nan, ni nan relayon konjigal yo. Bagay sa yo transmèt de generasyon an generasyon gras ak lafanmi, lekol, lakilti, lwa peyia. Pou fini, pèsepsyon sa yo medanm yo gen de seksyalite yo a makonen ak yon seri de enterè ekonomik ak politik ki gen nan sosyete a. Resilta rechèch sa a fe plizyè bagay. Premyèman li pemèt nou genyen dokiman syantifik sou seksyalite fanm ak relasyon ki genyen ant fanm ak gason lè yap viv andedan kay, nan peyia. Dezyèmman, rezilta yo montre travayèz ak travayè sosyal yo an ayiti, kouma li enpotan pou yo ankourage medanm yo devlope pouvwa lajan lakay yo. Rezilta yo montre tou kouman li enpotan pou medanm ayisyènn yo chache rantre nan tout diskisyon kap fet nan sosyete ayisyèn nan sou kondisyon lavi fanm yo.

La gestion d’une entreprise expose l’employeur au risque de discrimination. Dans son acception originelle, la notion de discrimination vise les distinctions reposant sur un critère illicite. La mise en oeuvre effective de la prohibition des discriminations amène le juge à exiger de l’employeur qu’il justifie de façon pertinente ses décisions. L’entreprise est sommée de développer des outils lui permettant d’apprécier de manière objective les compétences de ses salariés. Au-delà de cet objectif initial, la lutte contre les discriminations doit dorénavant faciliter l’intégration d’un public défavorisé. Les notions d’égalité professionnelle, de diversité, d’actions positives et de discriminations indirectes font aujourd’hui parti du vocabulaire des entreprises. Bien qu’elles ne disposent pas toujours de leviers d’action efficaces pour agir, les pouvoirs publics les contraignent à négocier sur certains thèmes pour résorber les inégalités. L’employeur responsable ne peut ignorer cette métamorphose du concept de discrimination. Il doit déterminer les nouvelles frontières de ce risque afin de mettre en oeuvre les dispositifs adéquats pour faire obstacle à sa réalisation. / Managing a company incurs a risk of discrimination for the employer. In its original meaning, the notion of discrimination refers to distinctions based on an illegal criterion. To be effective, the prohibition of discriminations brings the judge to require that the employer give pertinent justifications of his/her decisions. The company is compelled to develop means of assessing in an objective manner employees’ professional skills. Beyond this initial objective, the fight against discriminations must now ease the integration of disadvantaged populations. The notions of equal access to employment, diversity, affirmative action and indirect discrimination are now part of companies’ vocabulary. Though companies do not always have effective leverage for action, public authorities force them to negotiate on certain subjects in order to reduce inequalities. A responsible employer cannot ignore this radical change in the concept of discrimination. He/she must now setthe new boundaries to this risk so as to implement adequate means to prevent its materializing.

Biodiversity loss is one of the major environmental threats facing the planet. Incentive-based conservation is one means to reduce human pressure on wildlife by providing economic incentives for resource-dependent people to protect the environment. Marine wildlife tourism is one of the fastest growing tourism sectors globally and is viewed as an important incentive-based approach for achieving marine conservation goals. However, few studies have linked participation in the provisioning of marine wildlife tourism activities with positive social and ecological conservation outcomes. The goal of this dissertation is to provide greater understanding of the conservation value of marine wildlife tourism using whale shark tourism as a case study with a main focus on social conservation outcomes amongst tourism providers. Positive changes in perceptions, attitudes and values towards target species and their environments can be an important element of incentive-based conservation. The study has the following objectives: (1) to assess the status of the global whale shark tourism industry, including types (e.g., captive, non-captive), real and potential impacts, conservation value and management challenges and best practices; (2) to examine the ethics of provisioning whale sharks in Oslob, Philippines, the largest, non-captive viewing site in the world; (3) to determine if working in ecotourism changed the attitudes and behaviours of locals towards whale sharks and the ocean, and if tourism type affects those outcomes; (4) to assess the marine wildlife value orientations of locals working in whale shark tourism to achieve greater understanding of the factors influencing their conservation attitudes and behaviours; (5) to explore the potential long-term impacts of poorly conceived incentive-based conservation projects on social and ecological conservation outcomes; and (6) to re-examine and update the conceptual and theoretical background for wildlife tourism in light of the findings of this study. Methods include a comprehensive literature review, tourist surveys, social media content analysis, and interviews with locals working in whale shark tourism at four sites in the Philippines. Results suggest that marine wildlife tourism can play an important role in changing locals’ attitudes and behaviours towards the focal species and habitat; however, smaller-scale, more established sites had greater conservation value than the mass tourism or failed sites suggesting that small-scale, community-based ecotourism is the best approach to meeting conservation goals of marine wildlife tourism. Yet, few tourism sites meet these standards. Global standards are needed to ensure whale shark tourism activities meet desired conservation goals. Such standards should include management requirements (e.g., licensing, mandatory education program) and interaction guidelines (e.g. minimum viewing distances, limits on the number of swimmers/boats, etc.). The findings also emphasise that economics should not be the only or primary metric used to measure conservation success; rather, the focus should be on assessing a more comprehensive range of social and ecological conservation outcomes of these activities. / Graduate / 2020-04-16

<p>This dissertation considers packet-switched wireless networks for transmission of variable-rate layered hybrid video streams. Target applications are video streaming and broadcasting services. The work can be divided into two main parts.</p><p>In the first part, a novel quality-scalable scheme based on coefficient refinement and encoder quality constraints is developed as a possible extension to the video coding standard H.264. After a technical introduction to the coding tools of H.264 with the main focus on error resilience features, various quality scalability schemes in previous research are reviewed. Based on this discussion, an encoder decoder framework is designed for an arbitrary number of quality layers, hereby also enabling region-of-interest coding. After that, the performance of the new system is exhaustively tested, showing that the bit rate increase typically encountered with scalable hybrid coding schemes is, for certain coding parameters, only small to moderate. The double- and triple-layer constellations of the framework are shown to perform superior to other systems.</p><p>The second part considers layered code streams as generated by the scheme of the first part. Various error propagation issues in hybrid streams are discussed, which leads to the definition of a decoder quality constraint and a segmentation of the code stream to transmit. A packetization scheme based on successive source rate consumption is drafted, followed by the formulation of the channel code rate optimization problem for an optimum assignment of available codes to the channel packets. Proper MSE-based error metrics are derived, incorporating the properties of the source signal, a terminate-on-error decoding strategy, error concealment, inter-packet dependencies, and the channel conditions. The Viterbi algorithm is presented as a low-complexity solution to the optimization problem, showing a great adaptivity of the joint source channel coding scheme to the channel conditions. An almost constant image qualiity is achieved, also in mismatch situations, while the overall channel code rate decreases only as little as necessary as the channel quality deteriorates. It is further shown that the variance of code distributions is only small, and that the codes are assigned irregularly to all channel packets.</p><p>A double-layer constellation of the framework clearly outperforms other schemes with a substantial margin. </p><p>Keywords — Digital lossy video compression, visual communication, variable bit rate (VBR), SNR scalability, layered image processing, quality layer, hybrid code stream, predictive coding, progressive bit stream, joint source channel coding, fidelity constraint, channel error robustness, resilience, concealment, packet-switched, mobile and wireless ATM, noisy transmission, packet loss, binary symmetric channel, streaming, broadcasting, satellite and radio links, H.264, MPEG-4 AVC, Viterbi, trellis, unequal error protection</p>

This dissertation considers packet-switched wireless networks for transmission of variable-rate layered hybrid video streams. Target applications are video streaming and broadcasting services. The work can be divided into two main parts. In the first part, a novel quality-scalable scheme based on coefficient refinement and encoder quality constraints is developed as a possible extension to the video coding standard H.264. After a technical introduction to the coding tools of H.264 with the main focus on error resilience features, various quality scalability schemes in previous research are reviewed. Based on this discussion, an encoder decoder framework is designed for an arbitrary number of quality layers, hereby also enabling region-of-interest coding. After that, the performance of the new system is exhaustively tested, showing that the bit rate increase typically encountered with scalable hybrid coding schemes is, for certain coding parameters, only small to moderate. The double- and triple-layer constellations of the framework are shown to perform superior to other systems. The second part considers layered code streams as generated by the scheme of the first part. Various error propagation issues in hybrid streams are discussed, which leads to the definition of a decoder quality constraint and a segmentation of the code stream to transmit. A packetization scheme based on successive source rate consumption is drafted, followed by the formulation of the channel code rate optimization problem for an optimum assignment of available codes to the channel packets. Proper MSE-based error metrics are derived, incorporating the properties of the source signal, a terminate-on-error decoding strategy, error concealment, inter-packet dependencies, and the channel conditions. The Viterbi algorithm is presented as a low-complexity solution to the optimization problem, showing a great adaptivity of the joint source channel coding scheme to the channel conditions. An almost constant image qualiity is achieved, also in mismatch situations, while the overall channel code rate decreases only as little as necessary as the channel quality deteriorates. It is further shown that the variance of code distributions is only small, and that the codes are assigned irregularly to all channel packets. A double-layer constellation of the framework clearly outperforms other schemes with a substantial margin. Keywords — Digital lossy video compression, visual communication, variable bit rate (VBR), SNR scalability, layered image processing, quality layer, hybrid code stream, predictive coding, progressive bit stream, joint source channel coding, fidelity constraint, channel error robustness, resilience, concealment, packet-switched, mobile and wireless ATM, noisy transmission, packet loss, binary symmetric channel, streaming, broadcasting, satellite and radio links, H.264, MPEG-4 AVC, Viterbi, trellis, unequal error protection

The main objective in sampling is to select a sample from a population in order to estimate some unknown population parameter, usually a total or a mean of some interesting variable. When the units in the population do not have the same probability of being included in a sample, it is called unequal probability sampling. The inclusion probabilities are usually chosen to be proportional to some auxiliary variable that is known for all units in the population. When unequal probability sampling is applicable, it generally gives much better estimates than sampling with equal probabilities. This thesis consists of six papers that treat unequal probability sampling from a finite population of units. A random sample is selected according to some specified random mechanism called the sampling design. For unequal probability sampling there exist many different sampling designs. The choice of sampling design is important since it determines the properties of the estimator that is used. The main focus of this thesis is on evaluating and comparing different designs. Often it is preferable to select samples of a fixed size and hence the focus is on such designs. It is also important that a design has a simple and efficient implementation in order to be used in practice by statisticians. Some effort has been made to improve the implementation of some designs. In Paper II, two new implementations are presented for the Sampford design. In general a sampling design should also have a high level of randomization. A measure of the level of randomization is entropy. In Paper IV, eight designs are compared with respect to their entropy. A design called adjusted conditional Poisson has maximum entropy, but it is shown that several other designs are very close in terms of entropy. A specific situation called real time sampling is treated in Paper III, where a new design called correlated Poisson sampling is evaluated. In real time sampling the units pass the sampler one by one. Since each unit only passes once, the sampler must directly decide for each unit whether or not it should be sampled. The correlated Poisson design is shown to have much better properties than traditional methods such as Poisson sampling and systematic sampling.

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Ce mémoire a étudié les perceptions de femmes haïtiennes vivant au Québec depuis moins de cinq ans de leurs relations sexuelles avec les hommes et de leurs rapports de couple. Après avoir opté pour une méthodologie de recherche qualitative, la théorie féministe intersectionnelle a été retenue comme cadre d’analyse. Des entretiens individuels semi-dirigés ont été menés auprès de 9 femmes haïtiennes, âgées de 18 à 60 ans et ayant immigré au Québec depuis moins de cinq ans. Les perceptions des femmes de la sexualité ont été appréhendées comme étant un ensemble de discours et de pratiques inter reliés, qui se construit dès l’enfance, et qui reproduit les types de rapports inégalitaires entre hommes et femmes qui existent dans la société haïtienne et dans leur couple. Ces rapports inégalitaires sont véhiculés entre les générations à travers la plupart des institutions sociales comme la famille, l’école, la culture, la législation. Ce processus de construction des perceptions de la sexualité est également influencé par des enjeux socio-économiques et de pouvoir. Les résultats de cette recherche permettent de disposer de données scientifiques sur la sexualité des femmes et les rapports de couple en Haïti et l’influence du processus migratoire. Ces résultats soulignent également la nécessité pour le travail social haïtien d’encourager le développement de l’empowerment économique des femmes et leur participation aux débats actuels de la société sur l’évolution de la condition féminine. / The purpose of this research was to explore the perceptions of Haitian women that had immigrated to Quebec in the past five years, of their sexual relationships with men and the extent to which it is reflected in the different types of conjugal relationships. After choosing a qualitative research method, the intersectional feminist theory has been adopted for the analysis. Individual semi-structured interviews were conducted with 9 Haitian women, aged 18 and 60 years and having immigrated to Quebec in the past five years. The women’s perceptions of sexual relationships have been reported as being a set of practices and discourses interrelated built since childhood and reproducing the unequal relationships between men and women that exist in the Haitian society and in the couples. These unequal relationships are transmitted through the generations and through most of the social institutions such as family, school, culture, laws. This process is also influenced by socio-economic and power issues. The results of this research give scientific data on women sexuality and couple relationships as well as the influence of immigration process. These results also emphasize the need for the Haitian social work to encourage the development of economic empowerment of women and their participation in current debates in society on the development of women. / Memwa sa a vle etidye ki pèsepsyon fanm ayisyèn yo genyen de rapò seksyel yo ak gason, e nan ki mezi pèsepsyon sa yo repwodwi kalite relasyon ki egziste ant yomenm ak nèg yo. Rechèch la chwazi yon metodoloji kalitativ, apresa li kenbe teyori feminis entèseksyonèl kom kad ki pou pemet li analize done li yo. Rechèch la nenen 9 antrevi mwatye ouvè, mwatye fèmen ak 9 fanm ayisyèn, ki genyen ant 18 ak 60 lane, epi ki imigre nan pwovens kebèk, nan peyi Kanada depi mwens pase 5 lane. Dapre rezilta rechèch la, pèsepsyon medanm yo genyen de seksyalite yo tradwi pa yon pakèt pawòl ak yon pakèt abitid ki mare ansanm. Medanm yo komanse ranmase bagay sayo depilè yo te timoun lakay paran yo pou jiskaske yo vin granmoun lakay pa yo. Fason sa yo medanm yo konprann seksyalite a tou, se yon bagay ki soti nan relasyon fòskote ki egziste ant fanm ak gason, ni nan sosyete ayisyènn nan, ni nan relayon konjigal yo. Bagay sa yo transmèt de generasyon an generasyon gras ak lafanmi, lekol, lakilti, lwa peyia. Pou fini, pèsepsyon sa yo medanm yo gen de seksyalite yo a makonen ak yon seri de enterè ekonomik ak politik ki gen nan sosyete a. Resilta rechèch sa a fe plizyè bagay. Premyèman li pemèt nou genyen dokiman syantifik sou seksyalite fanm ak relasyon ki genyen ant fanm ak gason lè yap viv andedan kay, nan peyia. Dezyèmman, rezilta yo montre travayèz ak travayè sosyal yo an ayiti, kouma li enpotan pou yo ankourage medanm yo devlope pouvwa lajan lakay yo. Rezilta yo montre tou kouman li enpotan pou medanm ayisyènn yo chache rantre nan tout diskisyon kap fet nan sosyete ayisyèn nan sou kondisyon lavi fanm yo.