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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.
31

The PATCH program for caregivers of children with gastrostomy tubes: promoting and teaching confidence for the home

Lopez, Maria Isabella 19 June 2019 (has links)
The PATCH Program: Promoting and Teaching Confidence for the Home is a distinct approach developed to address the problem of high emergency department visit (8.6%) and hospital readmission rates (3.9%) associated with pediatric gastrostomy tube (GT) placement (Goldin et al., 2016). Recent literature regarding negative outcomes associated with pediatric GT placement identified the failure of current GT education and training practices to properly prepare caregivers to manage care in the home (Berman et al., 2017; Franklin & Rodger, 2003; Russell, Jewell, Poskey, & Russell, 2018). Developed by an occupational therapist, the PATCH Program offers an innovative approach to reducing facility rates of negative pediatric GT-related outcomes through family-centered education and self-efficacy enhancing components. Theory-based and evidence-driven, the PATCH Program integrates problem-solving training, formal education, and interactive skills practice to empower caregivers in developing the skills and self-efficacy needed to manage their children’s GT care. Adopting an occupational therapy perspective, the PATCH Program acknowledges that effective home management of a child’s GT care is the product of careful integration of familial context, skills, resources, and support systems. This doctoral project (1) summarizes the theory and evidence base supporting the PATCH Program’s development, (2) describes the PATCH Program curriculum and approaches, and (3) outlines future directions for PATCH Program implementation, including evaluation, dissemination, and funding. The PATCH Program demonstrates the value occupational therapy offers to supporting families in successfully managing a child’s medically complex condition, to reducing post-surgical emergency department visits and hospital readmissions, and to promoting health and wellness among caregivers and families.
32

Techniques for Non-Intrusive Machine Energy and Health Modeling

AbuAli, Mohamed 28 September 2010 (has links)
No description available.
33

Contribution au pronostic d'une pile à combustible de type PEMFC : approche par filtrage particulaire / contribution to prognostics of fuel cells of PEMFC type : approach based on particle filtering

Jouin, Marine 10 December 2015 (has links)
Le développement de nouveaux convertisseurs d’énergie, plus efficients et plus respectueux de l’environnement, tels que les piles à combustibles, tend à s’accélérer. Leur diffusion à grande échelle suppose cependant des garanties en termes de sécurité et de disponibilité. Une solution possible pour ce faire est de développer des solutions de Prognostics and Health Management (PHM) de ces systèmes, afin de mieux les surveiller, anticiper les défaillances et recommander les actions nécessaires à l’allongement de leur durée de vie. Dans cet esprit, cette thèse porte sur la proposition d’une approche de pronostic dédiée aux piles à combustibles de types PEMFC à l’aide de filtrage particulaire.Le raisonnement s’attache tout d’abord à mettre en place une formalisation du cadre de travail ainsi que des exigences de mise en. Ceci se poursuit par le développement d’un modèle basé sur la physique permettant une estimation d’état de santé et de son évolution temporelle. L’estimation d’état est réalisée grâce à du filtrage particulaire. Différentes variantes de filtres sont considérées sur la base d’une de la littérature et de nouvelles propositions adaptées au PHM sont formulées et comparées à celles existantes. Les estimations d’état de santé fournies par le processus de filtrages ont utilisées pour réaliser des prédictions de l’état de santé futur du système, puis de sa durée devie résiduelle. L’ensemble des propositions est validé sur 4 jeux de données obtenus sur des PEMFC suivant des profils de mission variés. Les résultats montrent de bonnes performances de prédictions et d’estimations de durée de vie résiduelle avant défaillance. / The development of new energy converters, more efficient and environment friendly, such as fuelcells, tends to accelerate. Nevertheless, their large scale diffusion supposes some guaranties in termsof safety and availability. A possible solution to do so is to develop Prognostics and HealthManagement (PHM) on these systems, in order to monitor and anticipate the failures, and torecommend the necessary actions to extend their lifetime. In this spirit, this thesis deals with theproposal of a prognostics approach based on particle filtering dedicated to PEMFCs.The reasoning focuses first on setting a formalization of the working framework and theexpectations. This is pursued by the development of a physic-based modelling enabling a state ofhealth estimation and its evolution in time. The state estimation is made thanks to particle filtering.Different variants of filters are considered on the basis of the literature and new proposals adaptedto PHM are proposed and compared to existing ones. State of health estimates given by the filter areused to predict the future state of the system and its remaining useful life. All the proposals arevalidated on four datasets from PEMFC following different mission profiles. The results show goodperformances for predictions and remaining useful life estimates before failure.
34

Méthodologie d’élaboration d’un bilan de santé de machines de production pour aider à la prise de décision en exploitation : application à un centre d’usinage à partir de la surveillance des composants de sa cinématique / Machine health check methodology to help maintenance in operational condition : application to machine tool from its kinematic monitoring

Laloix, Thomas 11 December 2018 (has links)
Ce travail de thèse a été initié par Renault, en collaboration avec le Centre de Recherche en Automatique de Nancy (CRAN), dans le but de poser les bases d'une méthodologie générique permettant d'évaluer l'état de santé de moyens de production. Cette méthodologie est issue d’une réflexion conjointe machine - produit en lien avec les exigences industrielles. La méthodologie proposée est basée sur une approche PHM (Prognostics and Health Management) et est structurée en cinq étapes séquentielles. Les deux premières étapes sont développées dans ce travail de thèse et en constituent les contributions scientifiques majeures. La première originalité représente la formalisation des connaissance issues de la relation machine-produit. Cette connaissance est basée sur l'extension de méthodes existantes telle que l’AMDEC et l’HAZOP. La formalisation des concepts de connaissance et de leurs interactions est matérialisée au moyen d'une méta-modélisation basée sur une modélisation UML (Unified Modelling Language). Cette contribution conduit à l'identification de paramètres pertinents à surveiller, depuis le niveau du composant jusqu'au niveau de la machine. Ces paramètres servent ensuite d’entrée au processus d'élaboration du bilan de santé machine, qui représente la deuxième originalité de la thèse. L'élaboration de ces indicateurs de santé est basée sur des méthodes d’agrégation, telle que l'intégrale de Choquet, soulevant la problématique de l'identification des capacités. De cette façon, il est proposé un modèle global d'optimisation de l'identification des capacités multi-niveaux du système à travers l’utilisation d’Algorithmes Génétiques. La faisabilité et l'intérêt d'une telle démarche sont démontrés sur le cas de la machine-outil située à l'usine RENAULT de Cléon / This PhD work has been initiated by Renault, in collaboration with Nancy Research Centre in Automatic Control (CRAN), with the aim to propose the foundation of a generic PHM-based methodology leading to machine health check regarding machine-product joint consideration and facing industrial requirements. The proposed PHM-based methodology is structured in five steps. The two first steps are developed in this PhD work and constitute the major contributions. The first originality represents the formalization of machine-product relationship knowledge based on the extension of well-known functioning/dysfunctioning analysis methods. The formalization is materialized by means of meta-modelling based on UML (Unified Modelling Language). This contribution leads to the identification of relevant parameters to be monitored, from component up to machine level. These parameters serve as a basis of the machine health check elaboration. The second major originality of the thesis aims at the definition of health check elaboration principles from the previously identified monitoring parameters and formalized system knowledge. Elaboration of such health indicators is based on Choquet integral as aggregation method, raising the issue of capacity identification. In this way, it is proposed a global optimization model of capacity identification according to system multi-level, by the use of Genetic Algorithms. Both contributions are developed with the objective to be generic (not only oriented on a specific class of equipment), according to industrial needs. The feasibility and the interests of such approach are shown on the case of machine tool located in RENAULT Cléon Factory
35

Potencialidades e alcances do monitoramento como ferramenta de gestão da saúde / Potential and Scope of Monitoring as a Tool for Health Management

Grimm, Sylvia Christina de Andrade 15 March 2016 (has links)
No Brasil, a construção bem como as mudanças nos mais de vinte anos do Sistema Único de Saúde (SUS) tem demandado um crescente interesse em estratégias que valorizem o uso da informação em saúde. Cada vez mais as incertezas entre a complexidade deste sistema e as intervenções necessárias para atender os seus preceitos e as necessidades da população precisam de respostas ágeis e efetivas. A efetividade dos serviços e a equidade em sua prestação são cruciais na atenção à saúde e mostram-se como desafio frente à dificuldade de avaliação dos resultados das ações pela demora no impacto nos indicadores epidemiológicos clássicos. O monitoramento é uma prática que pode ser destacada pela agilidade nas respostas, porém é nítido o quanto a discussão sobre o assunto é pouco estabelecida na literatura disponível. Se apresenta como uma prática interativa e proativa que utiliza informações disponíveis com o potencial de organizar e divulgar rapidamente as descobertas feitas, gerar um aprendizado organizacional e apoiar o processo decisório. A proposta deste estudo considerou o Painel de Monitoramento da Secretaria Municipal da Saúde de São Paulo como ponto de partida para pesquisar sobre as potencialidades do monitoramento na gestão. Uma pesquisa de métodos mistos foi a opção metodológica para este trabalho que buscou aprofundar o marco referencial teórico sobre monitoramento, descrever e analisar criticamente as referências técnicas utilizadas para a construção da proposta e realizar um estudo de caso único em território descentralizado do município de São Paulo sobre a rotina local na sua utilização e com isso analisar as potencialidades e os alcances desta experiência na gestão municipal. Concluiu-se que o monitoramento por meio de indicadores selecionados a partir de dados secundários é uma estratégia oportuna de acompanhar a tendência de determinadas ações possibilitando assim a emissão de juízo de valor e tomada de decisão com rapidez. O aplicativo propicia aos gestores e técnicos informações relevantes que apoiam o processo decisório, além de possibilitar a sua utilização em diferentes contextos da gestão e portes territoriais. Por outro lado, a prática cotidiana é pautada por prioridades normativas, onde a precisão do registro, a coerência das fontes e a quantidade apontada sobrepõem-se à informação em si, o seu significado e as ações necessárias para o enfrentamento dos problemas. O uso da informação é cultura em construção e o Painel de Monitoramento traz a possibilidade de organizar, qualificar e difundir dados secundários dos diferentes sistemas de informação do Sistema Único de Saúde (SUS). Além disso, tem contribuído também no papel de fomentar as discussões sobre os diferentes temas que envolvem as prioridades de uma gestão em todos os níveis do sistema de saúde do município de São Paulo. / In Brazil, construction and changes in more than twenty years of the Unified Health System (SUS) has demanded an increasing interest in strategies to enhance the use of health information. Increasingly, uncertainties between the complexity of this system and the interventions required to meet its precepts and the population\'s needs require agile and effective responses. The effectiveness of services and equity in its provision are crucial in health care and shows up as large challenge facing the difficulty of effective evaluation of this attention for the delay in the impact on classical epidemiological indicators. Monitoring is a practice that can be highlighted by the responsiveness, but it is clear how the discussion on the subject not yet established in the available literature. It is presented as an interactive and proactive practice using information available with the potential to quickly organize and disseminate discoveries made, generate organizational learning and support decision making. This study considered the Monitoring Panel of the Health Department of São Paulo as a starting point to research on the potential monitoring in a management. A survey of mixed methods was the method chosen for this work that sought to deepen the theoretical framework on monitoring, review and critically analyze the theoretical foundations of tool construction and conduct a case study in a decentralized space in São Paulo on the routine site on its use and thus evaluate the potential and scope of this experience in municipal management. It was concluded that monitoring through indicators from secondary data is an agile strategy to follow the trend of certain actions thus enabling value-issue and decision making quickly. The application provides managers and technical relevant information supporting the decisionmaking process, and enable its use in different areas of management and territorial sizes. On the other hand, everyday practice is still guided by normative priorities, where the accuracy of the record, the consistency of sources, pointed amount, overrides the information itself, its meaning and the necessary actions to face the problems. The use of information is culture construction and Monitoring Panel brings the ability to organize, disseminate and qualify secondary data from different information systems of the National Health System (SUS). Moreover, it has also contributed in part to encouraging discussions on the different issues involving the priorities of management at all levels of the São Paulo municipal health system.
36

Potencialidades e alcances do monitoramento como ferramenta de gestão da saúde / Potential and Scope of Monitoring as a Tool for Health Management

Sylvia Christina de Andrade Grimm 15 March 2016 (has links)
No Brasil, a construção bem como as mudanças nos mais de vinte anos do Sistema Único de Saúde (SUS) tem demandado um crescente interesse em estratégias que valorizem o uso da informação em saúde. Cada vez mais as incertezas entre a complexidade deste sistema e as intervenções necessárias para atender os seus preceitos e as necessidades da população precisam de respostas ágeis e efetivas. A efetividade dos serviços e a equidade em sua prestação são cruciais na atenção à saúde e mostram-se como desafio frente à dificuldade de avaliação dos resultados das ações pela demora no impacto nos indicadores epidemiológicos clássicos. O monitoramento é uma prática que pode ser destacada pela agilidade nas respostas, porém é nítido o quanto a discussão sobre o assunto é pouco estabelecida na literatura disponível. Se apresenta como uma prática interativa e proativa que utiliza informações disponíveis com o potencial de organizar e divulgar rapidamente as descobertas feitas, gerar um aprendizado organizacional e apoiar o processo decisório. A proposta deste estudo considerou o Painel de Monitoramento da Secretaria Municipal da Saúde de São Paulo como ponto de partida para pesquisar sobre as potencialidades do monitoramento na gestão. Uma pesquisa de métodos mistos foi a opção metodológica para este trabalho que buscou aprofundar o marco referencial teórico sobre monitoramento, descrever e analisar criticamente as referências técnicas utilizadas para a construção da proposta e realizar um estudo de caso único em território descentralizado do município de São Paulo sobre a rotina local na sua utilização e com isso analisar as potencialidades e os alcances desta experiência na gestão municipal. Concluiu-se que o monitoramento por meio de indicadores selecionados a partir de dados secundários é uma estratégia oportuna de acompanhar a tendência de determinadas ações possibilitando assim a emissão de juízo de valor e tomada de decisão com rapidez. O aplicativo propicia aos gestores e técnicos informações relevantes que apoiam o processo decisório, além de possibilitar a sua utilização em diferentes contextos da gestão e portes territoriais. Por outro lado, a prática cotidiana é pautada por prioridades normativas, onde a precisão do registro, a coerência das fontes e a quantidade apontada sobrepõem-se à informação em si, o seu significado e as ações necessárias para o enfrentamento dos problemas. O uso da informação é cultura em construção e o Painel de Monitoramento traz a possibilidade de organizar, qualificar e difundir dados secundários dos diferentes sistemas de informação do Sistema Único de Saúde (SUS). Além disso, tem contribuído também no papel de fomentar as discussões sobre os diferentes temas que envolvem as prioridades de uma gestão em todos os níveis do sistema de saúde do município de São Paulo. / In Brazil, construction and changes in more than twenty years of the Unified Health System (SUS) has demanded an increasing interest in strategies to enhance the use of health information. Increasingly, uncertainties between the complexity of this system and the interventions required to meet its precepts and the population\'s needs require agile and effective responses. The effectiveness of services and equity in its provision are crucial in health care and shows up as large challenge facing the difficulty of effective evaluation of this attention for the delay in the impact on classical epidemiological indicators. Monitoring is a practice that can be highlighted by the responsiveness, but it is clear how the discussion on the subject not yet established in the available literature. It is presented as an interactive and proactive practice using information available with the potential to quickly organize and disseminate discoveries made, generate organizational learning and support decision making. This study considered the Monitoring Panel of the Health Department of São Paulo as a starting point to research on the potential monitoring in a management. A survey of mixed methods was the method chosen for this work that sought to deepen the theoretical framework on monitoring, review and critically analyze the theoretical foundations of tool construction and conduct a case study in a decentralized space in São Paulo on the routine site on its use and thus evaluate the potential and scope of this experience in municipal management. It was concluded that monitoring through indicators from secondary data is an agile strategy to follow the trend of certain actions thus enabling value-issue and decision making quickly. The application provides managers and technical relevant information supporting the decisionmaking process, and enable its use in different areas of management and territorial sizes. On the other hand, everyday practice is still guided by normative priorities, where the accuracy of the record, the consistency of sources, pointed amount, overrides the information itself, its meaning and the necessary actions to face the problems. The use of information is culture construction and Monitoring Panel brings the ability to organize, disseminate and qualify secondary data from different information systems of the National Health System (SUS). Moreover, it has also contributed in part to encouraging discussions on the different issues involving the priorities of management at all levels of the São Paulo municipal health system.
37

An investigation into the prognosis of electromagnetic relays

Wileman, Andrew John January 2016 (has links)
Electrical contacts provide a well-proven solution to switching various loads in a wide variety of applications, such as power distribution, control applications, automotive and telecommunications. However, electrical contacts are known for limited reliability due to degradation effects upon the switching contacts due to arcing and fretting. Essentially, the life of the device may be determined by the limited life of the contacts. Failure to trip, spurious tripping and contact welding can, in critical applications such as control systems for avionics and nuclear power application, cause significant costs due to downtime, as well as safety implications. Prognostics provides a way to assess the remaining useful life (RUL) of a component based on its current state of health and its anticipated future usage and operating conditions. In this thesis, the effects of contact wear on a set of electromagnetic relays used in an avionic power controller is examined, and how contact resistance combined with a prognostic approach, can be used to ascertain the RUL of the device. Two methodologies are presented, firstly a Physics based Model (PbM) of the degradation using the predicted material loss due to arc damage. Secondly a computationally efficient technique using posterior degradation data to form a state space model in real time via a Sliding Window Recursive Least Squares (SWRLS) algorithm. Health monitoring using the presented techniques can provide knowledge of impending failure in high reliability applications where the risks associated with loss-of-functionality are too high to endure. The future states of the systems has been estimated based on a Particle and Kalman-filter projection of the models via a Bayesian framework. Performance of the prognostication health management algorithm during the contacts life has been quantified using performance evaluation metrics. Model predictions have been correlated with experimental data. Prognostic metrics including Prognostic Horizon (PH), alpha-Lamda (α-λ), and Relative Accuracy have been used to assess the performance of the damage proxies and a comparison of the two models made.
38

Prognostics and health management of power electronics

Alghassi, Alireza January 2016 (has links)
Prognostics and health management (PHM) is a major tool enabling systems to evaluate their reliability in real-time operation. Despite ground-breaking advances in most engineering and scientific disciplines during the past decades, reliability engineering has not seen significant breakthroughs or noticeable advances. Therefore, self-awareness of the embedded system is also often required in the sense that the system should be able to assess its own health state and failure records, and those of its main components, and take action appropriately. This thesis presents a radically new prognostics approach to reliable system design that will revolutionise complex power electronic systems with robust prognostics capability enhanced Insulated Gate Bipolar Transistors (IGBT) in applications where reliability is significantly challenging and critical. The IGBT is considered as one of the components that is mainly damaged in converters and experiences a number of failure mechanisms, such as bond wire lift off, die attached solder crack, loose gate control voltage, etc. The resulting effects mentioned are complex. For instance, solder crack growth results in increasing the IGBT’s thermal junction which becomes a source of heat turns to wire bond lift off. As a result, the indication of this failure can be seen often in increasing on-state resistance relating to the voltage drop between on-state collector-emitter. On the other hand, hot carrier injection is increased due to electrical stress. Additionally, IGBTs are components that mainly work under high stress, temperature and power consumptions due to the higher range of load that these devices need to switch. This accelerates the degradation mechanism in the power switches in discrete fashion till reaches failure state which fail after several hundred cycles. To this end, exploiting failure mechanism knowledge of IGBTs and identifying failure parameter indication are background information of developing failure model and prognostics algorithm to calculate remaining useful life (RUL) along with ±10% confidence bounds. A number of various prognostics models have been developed for forecasting time to failure of IGBTs and the performance of the presented estimation models has been evaluated based on two different evaluation metrics. The results show significant improvement in health monitoring capability for power switches. Furthermore, the reliability of the power switch was calculated and conducted to fully describe health state of the converter and reconfigure the control parameter using adaptive algorithm under degradation and load mission limitation. As a result, the life expectancy of devices has been increased. These all allow condition-monitoring facilities to minimise stress levels and predict future failure which greatly reduces the likelihood of power switch failures in the first place.
39

Systems Health Management for Resilient Extraterrestrial Habitation

Murali Krishnan Rajasekharan Pillai (18390546) 17 April 2024 (has links)
<p dir="ltr">Deep-space extraterrestrial missions require operating, supporting, and maintaining complex habitat systems at light minutes from Earth.</p><p dir="ltr">These habitation systems operate in harsh, unforgiving environments, will be sparsely crewed, and must be more autonomous than current space habitats, as communication delays will severely constrain Earth-based support.</p><p dir="ltr">Long-duration missions, limited knowledge of the extraterrestrial environment, and the need for self-sufficiency make these habitats vulnerable to a wide range of risks and failures, many of which are impossible to premeditate.</p><p dir="ltr">Therefore, it is necessary to design these systems to be resilient to faults and failures, thoughtfully designed to be situationally aware of their operational state and engage control mechanisms that maintain safe operations when migrating towards unsafe regions of operation.</p><p dir="ltr">Resilience-oriented design of such systems requires a holistic systems approach that represents the system's dynamic behavior, its control-oriented behaviors, and the interactions between them as it navigates through regions of safe and unsafe operations.</p><p dir="ltr">Only through this integrated approach can we fully understand how the system will behave under various conditions and design controls to prevent performance loss and ensure resilient operations.</p><p dir="ltr">Systems health management (SHM) is a key component for the resilience-oriented design of extraterrestrial habitats.</p><p dir="ltr">SHM capabilities enable intelligent autonomous control capabilities that can:</p><p dir="ltr">a) sense, diagnose, and isolate the root causes of anomalies,</p><p dir="ltr">b) predict how the system's behavior may evolve, and</p><p dir="ltr">c) select and execute recovery actions to restore system performance when appropriate.</p><p dir="ltr">Modern SHM technologies increasingly rely on intelligent autonomous control capabilities to manage system health and adapt behavior to maintain system performance.</p><p dir="ltr">This is achieved through complex nonlinear informational dependencies and control feedback loops that are difficult to design and verify using traditional risk assessment and resilience engineering methods.</p><p dir="ltr">This research contributes to enhancing the conceptual and preliminary design phases for developing resilient complex systems with embedded intelligent control-oriented behaviors.</p><p dir="ltr">It presents the required systems engineering tools and frameworks, enabling us to study the dynamic behavior of systems as they approach and recover from unsafe operations.</p><p dir="ltr">Further, it demonstrates how these tools and frameworks can quantify and gain insights into system resilience and support engineering decisions.</p><p dir="ltr">The work is contextualized within the broader systems engineering approach for designing complex, resilient extraterrestrial habitation systems.</p>
40

解析健康管理產業的商業模式-以M工司為例 / Analysis the Bussiness Model of The Health Management-As Example of M Company

張維寬, Chang, Wei Kuan Unknown Date (has links)
隨著國民平均餘命的延長,人民對於自身健康管理的觀念也從治療疾病進步到預防疾病。因此健康管理的醫療機構已經如雨後春筍般到處林立。對於有興趣想跨入健康管理的後進者,如何從中找到商機的切入點及新的創新商業模式,期許能在市場上佔有一定的位置,將是本篇論文探討的目的。 藉由分析、探討M公司的過往經營路程經驗與商業模式的創新變革,希冀提供台灣的健康管理同業們,在面對台灣醫療市場的萎縮及全世界老年化時代的來臨的,能夠共同開創新市場之策略觀點及經營規劃參考,因地制宜地結合台灣醫療優勢及中國廣大市場,創造一個雙贏的局面。

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