<p>Promotion of exclusive breastfeeding (EBF), (giving breast milk only without any solids or liquids), has proved to be very challenging in the South African context, although this infant feeding practice has been found to protect babies against diarrhoea and respiratory tract infections and to carry a lower risk of HIV infection than mixed feeding (breastfeeding combined with formula or solids). Study design: The PROMISE-EBF study is a multi-country cluster randomised trial to examine peer support to promote exclusive breastfeeding in Africa. For the South African site in the PROMISE-EBF study, three sites, Paarl, Rietvlei and Umlazi, were selected because of their different geographic settings and each site operated as a separate stratum for cluster selection and randomisation purposes. The clusters were then randomised into intervention and control arms making a total of 17 clusters in each arm. HIV positive and negative women in the intervention arm received support on their choice of infant feeding from the peer supporters who visited them at their homes while the women in the control group only received the standard infant feeding counselling and support provided by health care&nbsp / workers at health facilities. Data collection: Mothers were interviewed at recruitment during the antepartum period to establish eligibility, obtain informed consent and data on socio-economic status. Home visits were scheduled for data collection by trained data collectors at 3, 6, 12 and 24 weeks after birth. Analysis of results: This mini-thesis was a secondary analysis of the PROMISE-EBF data focusing on the South African data only. The data was adjusted for clustering and analysed using SAS. Comparison of variables between the intervention and control groups within sites was done. Results: A significant difference, regarding counselling and infant feeding practices, was observed among all women who received peer support compared to those who received the standard antenatal counselling, with more women in the intervention group (20.5%) practising EBF than those in the control group (12.8%) by Week 3. When the women‟s HIV status was considered, more than 65% of HIV positive and 40% of HIV negative women practised MF and EFF (giving formula milk only with no breast milk) throughout the study, respectively, regardless of the group they were in. For women who hadintended to practise EBF at recruitment, 33% in the control group and 20% in the intervention group actually practised EBF by Week 3. Regarding disclosure and feeding choice, 77.4% of women who had disclosed their HIV status actually practised MF versus 8.6% who practised EBF by Week 3.Conclusion: Community peer counselling should be strengthened as the results from this study showed that a high percentage of women who practised EBF were those who had received counselling, irrespective of their HIV status. The high percentage of HIV positive women who practised high risk feeding, despite receiving infant counselling, is of concern. Disclosure of the women‟s HIV status did not translate to them practising low risk infant feeding methods, which may suggest that there are other issues that determine the women‟s choice of infant feeding.</p>

<p>Promotion of exclusive breastfeeding (EBF), (giving breast milk only without any solids or liquids), has proved to be very challenging in the South African context, although this infant feeding practice has been found to protect babies against diarrhoea and respiratory tract infections and to carry a lower risk of HIV infection than mixed feeding (breastfeeding combined with formula or solids). Study design: The PROMISE-EBF study is a multi-country cluster randomised trial to examine peer support to promote exclusive breastfeeding in Africa. For the South African site in the PROMISE-EBF study, three sites, Paarl, Rietvlei and Umlazi, were selected because of their different geographic settings and each site operated as a separate stratum for cluster selection and randomisation purposes. The clusters were then randomised into intervention and control arms making a total of 17 clusters in each arm. HIV positive and negative women in the intervention arm received support on their choice of infant feeding from the peer supporters who visited them at their homes while the women in the control group only received the standard infant feeding counselling and support provided by health care&nbsp / workers at health facilities. Data collection: Mothers were interviewed at recruitment during the antepartum period to establish eligibility, obtain informed consent and data on socio-economic status. Home visits were scheduled for data collection by trained data collectors at 3, 6, 12 and 24 weeks after birth. Analysis of results: This mini-thesis was a secondary analysis of the PROMISE-EBF data focusing on the South African data only. The data was adjusted for clustering and analysed using SAS. Comparison of variables between the intervention and control groups within sites was done. Results: A significant difference, regarding counselling and infant feeding practices, was observed among all women who received peer support compared to those who received the standard antenatal counselling, with more women in the intervention group (20.5%) practising EBF than those in the control group (12.8%) by Week 3. When the women‟s HIV status was considered, more than 65% of HIV positive and 40% of HIV negative women practised MF and EFF (giving formula milk only with no breast milk) throughout the study, respectively, regardless of the group they were in. For women who hadintended to practise EBF at recruitment, 33% in the control group and 20% in the intervention group actually practised EBF by Week 3. Regarding disclosure and feeding choice, 77.4% of women who had disclosed their HIV status actually practised MF versus 8.6% who practised EBF by Week 3.Conclusion: Community peer counselling should be strengthened as the results from this study showed that a high percentage of women who practised EBF were those who had received counselling, irrespective of their HIV status. The high percentage of HIV positive women who practised high risk feeding, despite receiving infant counselling, is of concern. Disclosure of the women‟s HIV status did not translate to them practising low risk infant feeding methods, which may suggest that there are other issues that determine the women‟s choice of infant feeding.</p>

[pt] Este trabalho mostra a implantação de técnicas de Controle Estatístico de Processo (CEP) em uma indústria de cosméticos, em uma situação em que as técnicas convencionais não são aplicáveis. O processo a ser controlado é constituído de oito canais, que produzem em um mesmo instante de tempo oito unidades de um mesmo produto. Tal processo possui a peculiaridade de ter médias variáveis no tempo, mesmo em estado de controle estatístico. Como os métodos de controle propostos na literatura para processos com múltiplos canais têm como premissa médias constantes ao longo do tempo e os canais terem médias e variâncias semelhantes, tais métodos não são aplicáveis ao processo em questão. Para o CEP do processo, então, foi desenvolvida uma metodologia adaptada à realidade da empresa, que conjuga os princípios de group charts e de gráficos de controle de aceitação. Foi ainda realizada uma revisão bibliográfica de algumas técnicas de controle estatístico de processos com múltiplos canais, contemplando métodos tradicionais e não tradicionais. / [en] This study shows the implantation of techniques of Statistical Process Control (SPC) in a cosmetics industry, in a situation in which conventional techniques are not applicable. The process to be controlled is composed of eight streams, which produce eight units of the product at a time. The process has the peculiarity that the means of the streams change in time, even in a condition of statistical control. The control schemes proposed in the literature hitherto for multiple-stream processes assume constant means, and streams with similar means and variance, and are therefore not applicable to this process. A new scheme was then developed for the statistical control of the process, which blends the principles of the group charts and of acceptance control charts. A review was also presented of some techniques of statistical control of multiple-stream processes, including traditional and more recent methods.

[pt] Esta dissertação trata do controle estatístico de processos (CEP) multi-canal, assunto pouco tratado na literatura especializada. As técnicas encontradas na literatura pressupõem condições de validade nem sempre verificadas na prática, a saber: medidas sucessivas efetuadas em cada canal independentes e identicamente distribuídas; todos os canais ajustados, com mesma média e desvio-padrão; e (na maioria dos trabalhos) canais independentes, sem correlação cruzada. O estudo foi motivado por um caso real, em que nenhuma dessas condições se verifica. Este trabalho propõe adaptações e extensões de técnicas existentes para lidar com processos nessa situação; detalha como aplicá-las; ilustra sua aplicação no caso prático analisado; discute limitações e propõe alternativas, e inicia uma discussão sobre as diferentes condições (características das situações práticas) em que cada uma das alternativas é mais apropriada. O trabalho iniciou- se com uma análise exploratória dos processos da empresa, de modo a permitir um diagnóstico do CEP que vinha sendo realizado, e fundamentar a proposta de um novo esquema de controle, mais adequado. O esquema proposto, aplicado aos dados, sinalizou problemas com os processos que as técnicas empregadas não sinalizavam. Embora, em virtude dos prazos para finalização da dissertação e da programação da produção da empresa, que teve interrupções, não tenha sido possível incluir nesta análise a investigação de causas especiais, com revisão dos limites de controle e utilização dos gráficos assim revistos no monitoramento on line, para fins de acompanhamento do desempenho do esquema proposto, mesmo assim a aplicação desse esquema aos dados disponíveis demonstrou ser ele mais sensível a causas especiais que os gráficos que vinham sendo utilizados, e levantou algumas questões, não abordadas na literatura, que são indicadas para pesquisa futura. / [en] This dissertation tackles the problem of statistical control of multi-channel processes, which has been scarcely dealt with in the specialized literature. The techniques found in the literature assume validity conditions which are not always verified in practice, namely: successive measurements taken in each channel should be independent an identically distributed; all the channels should be adjusted, with same mean and standard deviation; and most works assume the channels to be independent, with no cross correlation. The study was motivated by a real case, in which no one of these conditions holds. This work proposes adaptations and extensions of existing techniques in order to deal with this and similar real situations; details the application of the adapted/extended techniques; illustrates their application in the case under analysis; discusses limitations and proposes alternatives, and initiates a discussion about the different conditions (practical situations´ characteristics) in which each alternative is most appropriate. The work began with an exploratory data analysis of the enterprise´s production processes, so as to enable a diagnosis of the statistical process control procedures that were in use, and serve as a basis for the proposal of a new, more adequate, control scheme. The proposed scheme, when applied to the data, signalled problems with the processes which the techniques in use did not signal. Due to the deadlines for ending this dissertation and to programmed interruptions in the production, it has not been possible to include in the analysis the search for special causes with corresponding revisions of the charts´ control limits and the use of the revised charts in on-line monitoring, for the purposes of feedback on the proposed scheme´s performance. Its application to the available data has nevertheless shown it more sensitive to special causes than the charts that were in use, and raised some issues not approached in the literature, which are left as indications for future research.

No description available.

Thermodynamic processes in finite time are in general irreversible. But there are chances to avoid irreversibility. For instance, there are canonical ensembles of special quantum systems with a given probability distribution describing the likelihood to find the system at time t=0 in a particular state with energy E_i(0), which can be controlled in a specific way, such that the initial probability distribution is recovered at the end of the process (t=T), but the state energies did change, hence E_i(0) is not equal to E_i(T). This allows to change thermodynamic quantities (expectation values) adiabatically, reversibly and in finite time. Such special processes are called Shortcuts to Adiabaticity. The presented thesis analyzes the origin of these shortcuts utilizing special Hamiltonian systems with dynamical algebra. Their main feature is to provide canonical invariance, which means a canonical ensemble stays canonical under Hamiltonian dynamics. This invariance carried by the dynamical algebra will be discussed using Lie group theory. In addition, the persistence of the dynamical algebra with respect to calculating expectation values will be deduced. This allows to benefit from all intrinsic symmetries within the discussion of ensemble trajectories. In consequence, these trajectories will evolve under Hamiltonian dynamics on a specific manifold given by the so-called Casimir companion. In addition, the deformation of this manifold due to non-Hamiltonian (dissipative) dynamics will be discussed, which allows to present a framework for modeling irreversible processes based on Hamiltonian systems with dynamical algebra. An application of this framework based on the parametric harmonic oscillator will be presented by determining time-optimal controls for transitions between two equilibrium as well as between non-equilibrium and equilibrium states. The latter one will lead to time-optimal equilibration strategies for a statistical ensemble of parametric harmonic oscillators. / Thermodynamische Prozesse in endlicher Zeit sind im Allgemeinen irreversibel. Es gibt jedoch Möglichkeiten, diese Irreversibilität zu umgehen. Ein kanonisches Ensemble eines speziellen quantenmechanischen Systems kann zum Beispiel auf eine ganz spezielle Art und Weise gesteuert werden, sodass nach endlicher Zeit T wieder eine kanonische Besetzungverteilung hergestellt ist, sich aber dennoch die Energie des Systems geändert hat (E(0) ungleich E(T)). Solche Prozesse erlauben das Ändern thermodynamischer Größen (Ensemblemittelwerte) der erwähnten speziellen Systeme in endlicher Zeit und auf eine adiabatische und reversible Art. Man nennt diese Art von speziellen Prozessen Shortcuts to Adiabaticity und die speziellen Systeme hamiltonsche Systeme mit dynamischer Algebra. Die vorliegende Dissertation hat zum Ziel den Ursprung dieser Shortcuts to Adiabaticity zu analysieren und eine Methodik zu entwickeln, die es erlaubt irreversible thermodynamische Prozesse adequat mittels dieser speziellen Systeme zu modellieren. Dazu wird deren besondere Eigenschaft ausgenutzt, die kanonische Invarianz, d.h. ein kanonisches Ensemble bleibt kanonisch bezüglich hamiltonscher Dynamik. Der Ursprung dieser Invarianz liegt in der dynamischen Algebra, die mit Hilfe der Theorie der Lie-Gruppen näher betrachtet wird. Dies erlaubt, eine weitere besondere Eigenschaft abzuleiten: Die Ensemblemittelwerte unterliegen ebenfalls den Symmetrien, die die dynamische Algebra widerspiegelt. Bei näherer Betrachtung befinden sich alle Trajektorien der Ensemblemittelwerte auf einer Mannigfaltigkeit, die durch den sogenannten Casimir Companion beschrieben wird. Darüber hinaus wird nicht-hamiltonsche/dissipative Dynamik betrachtet, welche zu einer Deformation der Mannigfaltigkeit führt. Abschließend wird eine Zusammenfassung der grundlegenden Methodik zur Modellierung irreversibler Prozesse mittels hamiltonscher Systeme mit dynamischer Algebra gegeben. Zum besseren Verständnis wird ein ausführliches Anwendungsbeispiel dieser Methodik präsentiert, in dem die zeitoptimale Steuerung eines Ensembles des harmonischen Oszillators zwischen zwei Gleichgewichtszuständen sowie zwischen Gleichgewichts- und Nichtgleichgewichtszuständen abgeleitet wird.