Дисертації: "Health Management (PHM)"

1

Wang, Xiaoyang. "Aircraft fuel system prognostics and health management." Thesis, Cranfield University, 2012. http://dspace.lib.cranfield.ac.uk/handle/1826/7214.

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This thesis contains the specific description of Group Design Project (GDP) and Individual Research Project (IRP) that are undertaken by the author and form part of the degree of Master of Science. The target of GDP is to develop a novel and unique commercial flying wing aircraft titled FW-11. FW-11 is a three-year collaborative civil aircraft project between Aviation Industry Corporation of China (AVIC) and Cranfield University. According to the market analysis result conducted by the author, 250 seats capacity and 7500 nautical miles were chosen as the design targets. The IRP is the further study of GDP, which is to enhance the competitive capability by deploying prognostics and health management (PHM) technology to the fuel system of FW-11. As a novel and brand-new technology, PHM enables the real-time transformation of system status data into alert and maintenance information during all ground or flight operating phases to improve the aircraft reliability and operating costs. Aircraft fuel system has a great impact on flight safety. Therefore, the development of fuel system PHM concept is necessary. This thesis began with an investigation of PHM, then a safety and reliability analysis of fuel system was conducted by using FHA, FMEA and FTA. According to these analyses, fuel temperature diagnosis and prognosis were chosen as a case study to improve the reliability and safety of FW-11. The PHM architecture of fuel temperature had been established. A fuel temperature prediction model was also introduced in this thesis.

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Demus, Justin Cole. "Prognostic Health Management Systems for More Electric Aircraft Applications." Miami University / OhioLINK, 2021. http://rave.ohiolink.edu/etdc/view?acc_num=miami1631047006902809.

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3

Bagheri, Behrad. "Decentralized Federated Autonomous Organizations for Prognostics and Health Management." University of Cincinnati / OhioLINK, 2020. http://rave.ohiolink.edu/etdc/view?acc_num=ucin1592133991337126.

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4

Lamoureux, Benjamin. "Development of an Integrated Approach for PHM - Prognostics and Health Management : Application to a Turbofan Fuel System." Thesis, Paris, ENSAM, 2014. http://www.theses.fr/2014ENAM0018/document.

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Pour les constructeurs de moteurs d'avions comme Snecma, la disponibilité est un des enjeux clés de l'avenir. En effet, la limitation des retards et annulations de vols ainsi que la réduction de la fréquence et de la durée des opérations de maintenance pourraient entraîner des économies importantes. Pour accroître la disponibilité, l'outil le plus utilisé actuellement est le "prognostics and health management" (PHM). La première contribution de la thèse est de proposer des cadres terminologique et fonctionnel pour le développement du PHM adapté aux spécificités des moteurs d'avions. Par la suite, une approche intégrée basée sur le nouveau modèle en V3 est formalisée. La seconde contribution est un processus basé sur les modèles pour le développement de la partie embarquée chargée de l'extraction des indicateurs de santé. Elle est basée sur l'analyse de sensibilité, la régression par vecteurs supports et des nouveaux indicateurs de performances. Puisque ce processus est réalisé avant l'entrée en service, les données stochastiques sont obtenues par propagation d'incertitudes. Pour surmonter les temps de calcul liés aux évaluations du modèle, des métamodèles sont utilisés. Plus particulièrement, la troisième contribution de la thèse est une technique originale combinant régression par vecteurs supports et Krigeage. L'approche globale est finalement testée sur le système carburant d'un moteur d'avion. Les résultats sont prometteurs, tant au niveau industriel pour les précieuses informations qu'elle fournit sur la qualité du jeu d'indicateurs de santé qu'au niveau académique pour la précision apportée par la nouvelle approche du Krigeage-SVR
For manufacturers of aircraft engines such as Snecma, the increase of systems availability is one of the key challenges of the future. Indeed, the limitation of delays and cancellations and the reduction of maintenance operations frequency and duration could lead to important costs savings. To improve availability, the most proven tool is currently prognostics and health management (PHM). The first contribution of this thesis work is to propose complete terminological and functional frameworks for the development of PHM adapted to the specific application on aircraft engines. Subsequently, an integrated development approach based on the original V3-model is formalized. The second contribution is an original model-based process for the development of the embedded extraction of health indicators, based on sensitivity analysis, support vector regression and original performance indicators for the validation. Since it is aimed at being performed before the entry into service, the stochastic data are issued from Monte-Carlo based uncertainties propagation. In order to overcome the prohibitive computation time of the model evaluations, surrogate models are used. More particularly, the third contribution of this thesis work is an original technique combining support vector regression with Kriging. The whole approach is finally tested on an aircraft engine fuel system. The results are promising, both at the industrial level with the release of valuable information about the quality of the health indicators set and at the academic level with the proven accuracy of the novel SVR-Kriging approach

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5

Feng, Jianshe. "Methodology of Adaptive Prognostics and Health Management in Dynamic Work Environment." University of Cincinnati / OhioLINK, 2020. http://rave.ohiolink.edu/etdc/view?acc_num=ucin1593267012325542.

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6

Shi, Zhe. "Semi-supervised Ensemble Learning Methods for Enhanced Prognostics and Health Management." University of Cincinnati / OhioLINK, 2018. http://rave.ohiolink.edu/etdc/view?acc_num=ucin1522420632837268.

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7

Brown, Douglas W. "A prognostic health management based framework for fault-tolerant control." Diss., Georgia Institute of Technology, 2011. http://hdl.handle.net/1853/41132.

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The emergence of complex and autonomous systems, such as modern aircraft, unmanned aerial vehicles (UAVs) and automated industrial processes is driving the development and implementation of new control technologies aimed at accommodating incipient failures to maintain system operation during an emergency. The motivation for this research began in the area of avionics and flight control systems for the purpose to improve aircraft safety. A prognostics health management (PHM) based fault-tolerant control architecture can increase safety and reliability by detecting and accommodating impending failures thereby minimizing the occurrence of unexpected, costly and possibly life-threatening mission failures; reduce unnecessary maintenance actions; and extend system availability / reliability. Recent developments in failure prognosis and fault tolerant control (FTC) provide a basis for a prognosis based reconfigurable control framework. Key work in this area considers: (1) long-term lifetime predictions as a design constraint using optimal control; (2) the use of model predictive control to retrofit existing controllers with real-time fault detection and diagnosis routines; (3) hybrid hierarchical approaches to FTC taking advantage of control reconfiguration at multiple levels, or layers, enabling the possibility of set-point reconfiguration, system restructuring and path / mission re-planning. Combining these control elements in a hierarchical structure allows for the development of a comprehensive framework for prognosis based FTC. First, the PHM-based reconfigurable controls framework presented in this thesis is given as one approach to a much larger hierarchical control scheme. This begins with a brief overview of a much broader three-tier hierarchical control architecture defined as having three layers: supervisory, intermediate, and low-level. The supervisory layer manages high-level objectives. The intermediate layer redistributes component loads among multiple sub-systems. The low-level layer reconfigures the set-points used by the local production controller thereby trading-off system performance for an increase in remaining useful life (RUL). Next, a low-level reconfigurable controller is defined as a time-varying multi-objective criterion function and appropriate constraints to determine optimal set-point reconfiguration. A set of necessary conditions are established to ensure the stability and boundedness of the composite system. In addition, the error bounds corresponding to long-term state-space prediction are examined. From these error bounds, the point estimate and corresponding uncertainty boundaries for the RUL estimate can be obtained. Also, the computational efficiency of the controller is examined by using the number of average floating point operations per iteration as a standard metric of comparison. Finally, results are obtained for an avionics grade triplex-redundant electro-mechanical actuator with a specific fault mode; insulation breakdown between winding turns in a brushless DC motor is used as a test case for the fault-mode. A prognostic model is developed relating motor operating conditions to RUL. Standard metrics for determining the feasibility of RUL reconfiguration are defined and used to study the performance of the reconfigured system; more specifically, the effects of the prediction horizon, model uncertainty, operating conditions and load disturbance on the RUL during reconfiguration are simulated using MATLAB and Simulink. Contributions of this work include defining a control architecture, proving stability and boundedness, deriving the control algorithm and demonstrating feasibility with an example.

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Liu, Zongchang. "Cyber-Physical System Augmented Prognostics and Health Management for Fleet-Based Systems." University of Cincinnati / OhioLINK, 2018. http://rave.ohiolink.edu/etdc/view?acc_num=ucin1522321192371536.

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9

Abbas, Manzar. "System-level health assessment of complex engineered processes." Diss., Georgia Institute of Technology, 2010. http://hdl.handle.net/1853/37260.

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Condition-Based Maintenance (CBM) and Prognostics and Health Management (PHM) technologies aim at improving the availability, reliability, maintainability, and safety of systems through the development of fault diagnostic and failure prognostic algorithms. In complex engineering systems, such as aircraft, power plants, etc., the prognostic activities have been limited to the component-level, primarily due to the complexity of large-scale engineering systems. However, the output of these prognostic algorithms can be practically useful for the system managers, operators, or maintenance personnel, only if it helps them in making decisions, which are based on system-level parameters. Therefore, there is an emerging need to build health assessment methodologies at the system-level. This research employs techniques from the field of design-of-experiments to build response surface metamodels at the system-level that are built on the foundations provided by component-level damage models.

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10

Consumi, Michele. "Tecniche di manutenzione predittiva: sviluppo di un processo stocastico per la modellazione della degradazione di componenti meccanici." Master's thesis, Alma Mater Studiorum - Università di Bologna, 2021.

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Questo progetto di tesi si pone l’obiettivo di analizzare lo stato dell’arte in tema manutenzione predittiva e indagare a fondo, per poi applicare, uno degli approcci stocastici più utilizzati in questo campo: il processo di Wiener. Il progetto ha avuto inizio con la ricerca e lo studio dei più recenti e noti articoli scientifici in tema Prognostics and Health Management. Dopo la comprensione dello stato dell’arte, si è scelto di concentrarsi sullo studio dei modelli stocastici per lo studio dei processi di degradazione dei componenti meccanici. In particolare, l’analisi si è concentrata sullo studio delle varie formulazioni del processo di Wiener, uno dei principali metodi stocastici in ambito prognostico. Il modello matematico è stato, quindi, implementato sul software di calcolo Matlab al fine di verificarne il funzionamento e l’efficacia. La fase di test ha previsto inizialmente lo sfruttamento di dati simulati e successivamente l’utilizzo di dati di degradazione reali estratti da un prototipo meccanico dell’Università di Bologna. I risultati ottenuti dimostrano come il modello stocastico scelto sia un ottimo strumento per la descrizione del percorso di degradazione e guasto del componente meccanico analizzato. La corretta modellizzazione del processo di degradazione è il punto di partenza fondamentale per l’applicazione dei modelli prognostici per la stima della vita utile residua dei componenti (RUL). La tesi propone, infine, una propria proposta di modifica al modello base di Wiener in modo da poterne applicare l'applicabilità considerando anche le lavorazioni che implicano condizioni operative variabili.

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11

Gladwin, Jean. "An informational approach to health management in low-income countries." Thesis, University of Sheffield, 1999. http://etheses.whiterose.ac.uk/3491/.

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This thesis investigates the introduction of new information management strategies intended to promote an informational approach to management at the operational health service level in low-income countries. There is a lack of in-depth empirical research into the health information systems planning and implementation process in low-income countries which develops an understanding based on existing theory and research. Furthermore, a training package for managers, which is intended to strengthen health information management in low-income countries, has been introduced without independent evaluation. In order to understand the practice and attempts at improving information support to district level management in low-income countries, two ethnographic case studies are presented. The first follows the introduction of PHC MAP, the package mentioned, and the second follows the implementation of a non- computer-based health management information system in Uganda. The research methodology is informed by several approaches which fit within the interpretative, rather than the positivist tradition. Hence, the research question developed from the desire to understand and examine empirical situations. Furthermore, an exploratory approach was utilised rather than identifying theoretical frameworks prior to the field investigation. After the initial fieldwork, the diffusion of innovation framework, the concept of organisational forces existing in dynamic equilibrium, and different information systems development methodologies proved useful in interpreting the evidence collected. My research indicates that the design of PHC MAP and the health management information system focused on technological issues, to the detriment of the wider issues of technological innovation management, and organisational change. The implications of this research, for the practice of introducing new information strategies in order to develop an informational approach to management, are explored.

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Bouaziz, Mohammed Farouk. "Contribution à la modélisation Bayésienne de l'état de santé d'un système complexe : application à l'industrie du semi-conducteur." Phd thesis, Université de Grenoble, 2012. http://tel.archives-ouvertes.fr/tel-00993732.

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Pour maintenir leur compétitivité, les industries du semi-conducteur doivent être en mesure de produire des circuits intégrés en technologies avancées, avec des temps de cycle de plus en plus courts et à des coûts raisonnables. Un des axes d'amélioration réside dans le traitement des défaillances des équipements de production tenus responsables de plus de 50%des rejets produits. Cette thèse se fixe comme objectif de contribuer au développement d'une boucle réactive partant d'une dérive produit à la mise en place d'une solution appropriée tout en assurant un meilleur compromis entre disponibilité des équipements, coûts d'exploitation, qualité et compétitivité du produit. Joignant l'expertise humaine et les événements réels, nous nous sommes proposé ici de développer une méthodologie générique permettant de construire un modèle d'estimation du comportement des équipements de production (Equipment Health Factor EHF) à partir d'un raisonnement mathématique centré sur un formalisme probabiliste. L'approche a été amenée à sa validation expérimentale sur des outils, à base de réseaux Bayésiens, que nous avons développés. Les résultats obtenus amènent des éléments de décision permettant à l'industriel d'intervenir au plus tôt pour envisager par exemple de maintenir l'équipement avant qu'il n'ait dérivé. Cette thèse a été préparée dans le cadre du projet européen IMPROVE en collaboration avec STMicroelectronics, Lfoundry et Probayes

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Adindu, Anthonia U. "The effect of incongruity on quality of health information systems : Bama, Nigeria PHC case study." Thesis, University of Hull, 1995. http://hydra.hull.ac.uk/resources/hull:3692.

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Generally, organisations mobilise information from varying sources on which policies, plans, objectives and organisational management are predicated. indeed, everyone within organisation needs information to perform tasks, it is thus indispensable and its use so pervasive that a methodical approach for collection and processing is imperative. In health care organisations, involved with people and life, this is even of greater significance, in many instances allowable margin of error is narrow and can be devastating.Accurate and reliable information in clinical care for example cannot be compromised.On the other hand, adequate assessment of health services quality,effectiveness and efficiency depends on quality of information generated by the system, that is, accurate, relevant, timely, understandable and complete information. To achieve this, appropriate system design and operation is essential. Adoption of primary health care (PHC), in many developing countries in response to the Global 2000, necessitated establishment of chanisms for monitoring and evaluating effectiveness of services and programmes.Accordingly, in 1986 PHC was adopted in Nigeria, concomitantly, system monitoring and evaluation or the PHC Management Information System was effexted.The information system was envisaged to ameliorate the lack of reliable health information that has persisted since nception of modern health services in Nigeria. Findings in this and other studies indicate that existing health information systems have failed to provide accurate and reliable information, systems of data generation and processing are ineffective.The aim of this was to identify and understand factors that have contributed to the seemingly intractable and insalubrious information problem within the Nigerian health care system. It would be a herculean task for a lone researcher to undertake study of the entire health system, within resource and time limitations, data collection was therefore narrowed to the PHC level. Quality of the PHC management information system was assessed, with Bama Local Government as a case study. Focus was on understanding the information system's structure from a broad perspective to include, policies, objectives,established procedures; physical, material and human resources, in terms of their quality and quantity.Data collection was carried out using both qualitative and quantitative techniques. The structure, process and outcome models provided a framework for in-depth data collection, through observation, interview, review of records and administration of questionnaire, as well as for organisation and analysis of research data. The PHC MIS was followed through, from the village, health facility, local government, state and national levels.Study results suggest general ineffectiveness due to pervasive incongruity in the information system. In the first instance design of the MIS did not reflect information needs of community health workers and the community in general,who to the most part limited appreciation of the MIS structure, objectives to be achieved. Local and regional information need was not delineated, data collected had little relevance to local information needs, resource for systems operation was abysmal, skilled personnel and training provided severely inadequate.Consequently, data collection and processing was hampered, information produced often inaccurate, untimely, immense, irrelevant and unreliable. Data collected were neither analysed nor utilised. The information system was short of being integrated since 60% of functional units within the PHC department as well as related health organisations in the community ran parallel information systems.Research data point to serious incongruity in the organisation and management of the information system. Incongruity that resulted from factors within the organisation as well derived from events within the wider social environment, which however culminated in an effective and dysfunctional information system.Chapters one to three of the thesis deal with conceptual issues related to management information systems, organisational design and quality respectively. In chapter four methodological issues surrounding data collection were discussed. Empirical data and analysis are presented are presented in chapters five to seven. In chapter eight, an attempt was made to develop a model of organisational incongruity, applied to explicate research findings.Chapter nine focuses on measures toward establishment of an effective PHC information system in Nigeria, contributions of this study and suggestions for future research.

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Wood, David L., Brandon Rocque, Betsy Hopson, Katherine Barnes, and Kiana Johnson. "Transition Readiness Assessment Questionnaire Spina Bifida (TRAQ-SB) Module predicts clinical outcomes among youth and young adults with Spina Bifida." Digital Commons @ East Tennessee State University, 2019. https://doi.org/10.3233/PRM-180595.

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PURPOSE: In order to transition to adulthood and independence, youth with spina bifida must assume significant self-management responsibilities including monitoring for shunt malfunction, maintaining intact skin in areas that are insensate, and maintaining proper bowel and bladder function. Validated measures of specific spina bifida self-management skills are lacking and this hampers the ability of clinical personnel to support successful transition for youth with spina bifida. METHODS: We developed a self-report measure specific to SB self-management skills consistent with the framework of the Transition Readiness Assessment Questionnaire (TRAQ). To test the predictive validity of the tool we surveyed 90 youth and young adults ages 12-25 with spina bifida attending a multidisciplinary clinic participating in the National Spina Bifida Patient Registry (NSBPR). RESULTS: Adjusted for age, gender, race, insurance status and lesion level, higher scores on the TRAQ-SB (increased self-management) were negatively associated with urinary incontinence in the past month. Only lesion level, and not TRAQ-SB scores, was a significant predictor of stool incontinence and skin breakdown. CONCLUSIONS: Higher TRAQ-SB scores are negatively associated with bladder incontinence in youth with spina bifida. While stool continence and skin breakdown were not associated with TRAQ-SB scores, this relation is complex and may be obfuscated by either reporting bias or outcome measurement bias. To further refine the questionnaire and understand this relationship we need to field it prospectively in the SB network with larger samples. The TRAQ-SB questionnaire, however, does have value in the clinical setting to help promote the acquisition of specific self-management skills among youth with spina bifida.

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Johnson, Kiana, Brandon Rocque, Betsy Hopson, Katherine Barnes, Ogbebor Enaholo Omoike, and David L. Wood. "The Reliability and Validity of a Newly Developed Disease-Specific Transition Readiness Assessment Questionnaire: Transition Readiness Assessment Questionaire - Spina Bifida Suppplement (TRAQ-SB)." Digital Commons @ East Tennessee State University, 2019. https://doi.org/10.3233/PRM-180599.

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PURPOSE: The purpose of this study is to report preliminary evidence to support a new condition-specific measure of transition readiness that is theoretically grounded in the Stages of Changes framework. The Transition Readiness Assessment Questionnaire-Spina Bifida (TRAQ-SB) supplement is a newly developed tool used to measure independence and skill acquisition related to spina bifida. Similar to the Transition Readiness Assessment Questionnaire (TRAQ), the TRAQ-SB uses a 5-point Likert response set. METHODS: Working with a multi-disciplinary team with expertise in the care of children with spina bifida, the authors developed twelve items pertaining to main aspects of SB self-management. The items were reviewed and revised through several iterations by the team and patients. The items were then fielded at a spina bifida Specialty Clinic, where 93 consecutive patients 12–25 years of age were approached to participate and 90 were administered the 20-item TRAQ and a 12-item TRAQ-SB questionnaire. A principal component analysis (PCA) was conducted on the twelve items with oblique rotation (promax). Criterion validity was also assessed by examining the correlation of the TRAQ-SB supplement with the TRAQ and with age. RESULTS: Results of the factor analysis revealed that eleven of the twelve items loaded onto one factor with factor loadings ranging from 0.46 to 0.84. The scale yielded excellent internal reliability with a Cronbach alpha of 0.90. Correlations of the TRAQ-SB supplement scale score with the TRAQ overall scale score demonstrated good criterion validity (r= 0.74, p< 0.01). In addition, it was highly correlated with the TRAQ subscales, varying from 0.68 to 0.74 (all p< 0.01). Lastly, the TRAQ-SB was significantly correlated with age (r= 0.25, p< 0.01). CONCLUSIONS: Results of our analyses indicated that the TRAQ-SB demonstrated good internal reliability and criterion validity as evidenced by strong correlation with age and the validated TRAQ measure. The TRAQ-SB tool can be useful to incorporate transition readiness assessment and self-management training into routine care for adolescents with spina bifida.

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Shahin, Kamrul. "Modèle graphique probabiliste appliqué au diagnostic de l'état de santé des systèmes, au pronostic et à l'estimation de la durée de vie résiduelle." Electronic Thesis or Diss., Université de Lorraine, 2020. http://www.theses.fr/2020LORR0129.

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Cette thèse contribue au développement des recherches dans le domaine du Pronostic et Health Management : gestion de l’état de santé des systèmes complexes. Dans un contexte de management opérationnel et de sûreté de fonctionnement des systèmes, nous proposons d’étudier comment la modélisation par un Modèle Graphique Probabiliste Dynamique (MGPD) permet le diagnostic de l’état de santé courant d’un système, le pronostic de cet état et de l’évolution des dégradations, ainsi que l’estimation de sa durée de vie résiduelle en fonction de ses conditions opérationnelles. La dégradation des composants est en général inconnue et nécessite un arrêt du système pour être observée. Cependant, cela est difficile, voire impossible, durant l’exploitation du système. Néanmoins, un ensemble de grandeurs observables sur le système ou le composant peut caractériser le niveau de dégradation et faciliter l’estimation de la durée de vie résiduelle du composant et du système. Les MGPD offrent une approche adaptée à la modélisation de l’évolution de l’état de santé des systèmes et des composants. Nous étendons la modélisation classique des modèles de la famille des HMM vers les IOHMM pour permettre une propagation temporelle de l’incertitude afin de résoudre le problème de pronostic de l’état de santé et de l’estimation de la durée de vie résiduelle. Cette recherche comprend l’extension des algorithmes d’apprentissage et d’inférence appliqués aussi bien dans le cas d’un composant que pour un système structuré. Cette thèse a pour but de contribuer à lever les verrous scientifiques suivants : - Considérer l'état de santé du système par un modèle stochastique et apprendre les paramètres du modèle à partir des mesures disponibles sur le système. - Établir un diagnostic de l’état de santé du système et le pronostic de son évolution en intégrant plusieurs conditions opérationnelles. - Estimer la durée de vie résiduelle des composants et des systèmes structurés (série, parallèle) à partir de ses composants. L’enjeu est majeur, car le pronostic de la dégradation des composants du système permet de définir des stratégies soit de pilotage soit de maintenance par rapport à la durée de vie résiduelle du système. Cela permet la réduction de la probabilité d’occurrence d’un arrêt pour cause de dysfonctionnement du système, soit en ajustant la vitesse de dégradation pour s’accorder à un plan de maintenance préventif, soit en planifiant les interventions de maintenance de manière proactive
This thesis contributes to prognosis and health management for assessing health condition of complex systems. In the context of operational management and operational safety of systems, we propose to investigate how Dynamic Probabilistic Graphical Modelling (DPGM) can be used to diagnose the current health state of systems, prognostic the future health state, and the evolution of degradation, as well as estimate its remaining useful life based on its operating conditions. System degradation is generally unknown and requires shutting down the system to be observed. However, this is difficult or even impossible during system operation. Though, a set of observable quantities on a system or component can characterise the level of degradation and help to estimate the remaining useful life of components and systems. The DPGM provides an approach suitable for modelling the evolution of the health state of systems and components. The aim of this thesis is to transpose and capitalize on the experience of these previous works in a prognostic context on the basis of a more efficient DPGM taking into account the available knowledge on the system. We extend the classical HMM family models to the IOHMM to allow the time propagation of uncertainty to address prognostic problems. This research includes the extension of learning and inference algorithms. Variants of the HMM model are proposed to incorporate the operating environment into the prognosis. The aim of this thesis is to contribute to solving the following scientific locks: - Considering the state of health whatever the complexity of the system by a stochastic model and learning the model parameters from the available measurements on the system. - Establish a diagnosis of the state of health of the system and the prognosis of its evolution by integrating several operational conditions. - Estimate the remaining useful life of components and structured systems with series and parallel components. This is a major challenge because the prognosis of the degradation of system components makes it possible to define strategies for either control or maintenance in relation to the residual life of the system. This allows the reduction of the probability of occurrence of a shutdown due to a system malfunction either by adjusting the degradation speed to fit in with a preventive maintenance plan or by proactively planning maintenance interventions

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Mugaju, James. "Health Care Services for Child Survival and Performance-Based Management in Three Kosovo Municipalities." ScholarWorks, 2018. https://scholarworks.waldenu.edu/dissertations/5910.

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After the Republic of Kosovo's declaration of independence in 2008, new municipal structures were created with the charge of monitoring the delivery of health care services; yet, no mechanism for monitoring performance was ever implemented. With the public value theory as the foundation, the purpose of this multiple case study of 3 Kosovo municipalities was to understand issues surrounding the capacity of local government health department to monitor their performance related to the delivery of services. Relevant data were collected through focus-group discussions with 10 nurses, 9 directors of family medicine centers, and 12 municipal program managers. Purposeful semistructured interviews were conducted with 3 elected officials, 3 leaders of health care services, 3 policy leaders of relevant central-level ministries, and 9 participants from the national coalition of civil society organizations. All data were transcribed and coded per thematic analysis procedures. Results indicated that integrating the threefold value system of business value, social value, and governance value into municipal work plans and policy considerations will likely create a more solution-oriented service delivery at the municipal level. Furthermore, service delivery in the 3 municipalities appears to have improved over the past 5 years because of the pressure from active citizens, increased community engagement, and the institutionalization of home visits. Positive social change implications stemming from this study include the recommendation to central and local policy makers to fully integrate performance-based reporting systems into local legislation and policies. Such efforts can result in sustainable, equitable, and inclusive development, leading to stability and prosperity in Kosovo.

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18

Newton, Phillip J. "The management of dyspnoea in advanced heart failure." Thesis, View thesis, 2008. http://handle.uws.edu.au:8081/1959.7/35551.

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Heart failure is a cause of significant burden to both individuals and society. Individuals live with a disease where there is a decline in physical functioning, the experience of a range of symptoms including breathlessness and pain, frequent hospitalisations and death. The frequent hospital admissions that are usually precipitated by shortness of breath places an economic burden on the current health system. This burden of heart failure is expected to increase in the coming years due to factors such as the ageing population and improved survival from acute cardiac events. This current and predicted continuing burden has been recognised by the health system and has resulted in significant improvement in the pharmacotherapy and nonpharmacotherapy treatment of heart failure. Despite this improvement and with the exception of those few who receive cardiac transplantation, there is no cure for heart failure. Whist the advances in therapy have promoted significant improvements in heart failure management, symptoms including breathlessness (dyspnoea) remain a major issue. The Management of Dyspnoea in Advanced Heart Failure project explored and assessed the current therapeutic management of dyspnoea in advanced heart failure and examined two potential therapeutic options namely nebulised frusemide and long-term oxygen therapy. Following a comprehensive review of the nebulised frusemide literature, The Haemodynamic Effects of Nebulised Frusemide in Heart Failure study showed that nebulised frusemide did have an impact on the haemodynamic parameters of participants. Whilst many consider oxygen therapy as a common sense approach for breathlessness, the lack of scientific evidence for its use in chronic breathlessness with people who have normal or mildly low oxygen levels has prevented funding to supply oxygen therapy to this group of patients. The O2 Breathe Study is a palliative care study that is testing long-term home oxygen therapy versus medical air in patients who do meet the current funding arrangements. The analysis of the screening data showed that the symptom burden as a result of dyspnoea is similar to that seen in cancer and respiratory patients, and heart failure patients had lower levels of physical functioning than the respiratory group. Whilst the design of the studies in this thesis will not allow conclusions to be made regarding their efficacy for dyspnoea management in heart failure, they have provided preliminary data and hypotheses to be tested in the future.

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19

Fernandez, Ritin. "Development and evaluation of a health-related lifestyle self-management intervention for patients with acute coronary syndrome." Thesis, View thesis, 2007. http://handle.uws.edu.au:8081/1959.7/32587.

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Acute coronary syndrome (ACS), the acute manifestation of coronary heart disease (CHD), is the leading cardiovascular cause of mortality and morbidity globally, and represents one of the most common causes of acute medical admissions to Australian hospitals. Following medical and/or surgical management of ACS, lifestyle modification to reduce the underlying risk factors that contribute to the progression of the disease remains vital. Cardiac rehabilitation (CR) has been widely accepted as an intervention that can reduce mortality and modify risk factors for subsequent coronary events and cardiovascular disease. While the benefits of cardiac rehabilitation programs have been demonstrated, participation and adherence to these programs remain low for various reasons, particularly among patients whose treatment includes revascularisation with percutaneous coronary intervention. This method of revascularisation has become increasingly common due its immediate success, rapid procedural technique, short hospital stay and early return to work for patients of working age. The aim of this study was to develop and test the feasibility of an evidence-based health-related lifestyle management program for risk factor modification in patients with ACS undergoing percutaneous coronary intervention. Four distinct yet interrelated studies were undertaken as part of the Development and evaluation of a Health-related Lifestyle self-Management (HeLM) intervention for patients with ACS Project. Three of these studies informed the development of the HeLM intervention, which was based on the principles of chronic disease self-management and evidence-based practice that included best evidence from the literature, clinical expertise and patient preferences. The first study was a systematic review of the literature to identify the best available evidence of the effect of brief interventions for lifestyle modification in patients with CHD. Findings from the 17 trials included in the systematic review, although inconclusive suggest that brief structured interventions can have beneficial effects on risk factor modification and consequently on progression of CHD. The second study was a qualitative interview of CR coordinators to identify from their clinical expertise the influence of the Reducing Risk in Heart Disease guidelines on practice: the Implementation of the Cardiac Evidence-Based Reducing Risk in Heart Disease Guidelines (ICEBRG) study. Findings from this study indicated limited implementation of the guidelines due to various barriers relating to health services, CR programs, professional practice and the patient and their families. Despite these barriers, it was evident that CR coordinators were striving to overcome these odds and provide evidence-based care. The third study undertaken to identify patient preferences for CR was the Follow-up After percutaneous Coronary Treatment (FACT) Study. The findings indicated that although the majority of the participants had two or more risk factors, they lacked knowledge of the link between risk factors and CHD, and less than a third had attended CR. The main reasons for nonattendance included timing, distance to travel, length of program, work commitments and lack of motivation to attend the programs. Their suggestions for improvement included telephone follow-up and flexibility of the CR programs. This study also informed the development of a tool that can be used by clinicians to flag patients who are unlikely to attend traditional CR. Identification of these people will allow alternate strategies to reduce risk factors to be tailored to their needs. The findings from these three studies were used to develop the HeLM intervention. The final study was undertaken to assess the feasibility of the HeLM intervention that was based on evidence compared to standard treatment for promoting lifestyle modification. This study was undertaken in 51 participants who were followed up two weeks following the completion of the intervention. The findings demonstrated that patients found the information beneficial and were pleased to receive it in their homes. The telephone support was also extremely well received. The study enabled the program and the process for implementation to be refined and indicated that a large multicentre trial would be feasible. The HeLM may be a strategy that could reach patients who have thus far eluded traditional CR programs and support them to make the necessary lifestyle changes. It may also be an adjunct to traditional CR and have a synergistic effect in facilitating health-promoting behaviours in CHD patients. Studies of interventions for risk factor modification in participants with CHD require longer term follow-up to assess the effect of the intervention in the sustainability of behaviour modification. Further research is necessary to evaluate the long-term effects as well as the cost effectiveness of the intervention.

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20

Sahani, Mazrura. "Separate realities : community-based environmental management for health from the 'inside-out' and 'outside-in'." Thesis, View thesis, 2002. http://handle.uws.edu.au:8081/1959.7/131.

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Despite the tremendous achievement in economic development over the past four decades since independence, Malaysia is facing a problem of environmental degradation at a rapid pace. In searching for Malaysian approach to alter this trend, this thesis is written against a background of concern for a balanced development in economy and social wellbeing and simultaneously preserving the environment. The aim of the study is to identify an alternative approach in managing the local environment for health, starting from a value position of regard for local knowledge and abilities, and for scientists and administrators working together with local knowledge and abilities, and for scientists and administrators working together with local communities in their natural settings. Findings from this study offer a range of lessons for those who wish to integrate local and scientific knowledge. The research approach proved capable of documenting the separate realities of the place-based and the knowledge-based communities within a common interpretative framework. The place-based communities held realistic interpretations of their capacity to contribute to local sustainable development, distinct from one another and also distinct from the same events as perceived by the scientific community. The conclusion is drawn that each needs the other for any effective local application of scientific findings or government support. Finally, this has not been a study of top-down or bottom up but from the 'inside-out' with a small study of the 'outside-in.' It offers another perspective and an extra set of tools or strategies for the professionals' community to work with local communities in their environmental management for health. The desired outcome would be for the local communities to contribute as a full partner to the dominant scientific studies in designing local management strategies.

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21

Assaf, Abdallah G. "Modelling the efficiency of health care foodservice operations : a stochastic frontier approach." Thesis, View thesis, 2007. http://handle.uws.edu.au:8081/1959.7/39196.

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The important role of efficiency in the health care foodservice sector has been widely addressed in the literature. Different methods for assessing performance have been proposed. In general, most measures were calculated as simple ratios such as food and labour cost per meal or limited parametric techniques such as regression analysis. These approaches are meaningful indicators of which operational performance areas require attentions; however, problems arise when managers interpret partial productivity measures of this type as indicators of overall performance without considering the effects of other related variables. This could create further problems in complex applications such as the health care foodservice sector where multiple inputs (number of full time employees, energy cost, capital, overheads) outputs (number of meals and patient satisfaction) and environmental or interfering variables (age of equipment, quality of labour or skill level of employees and the degree of readiness of materials) should be considered in the assessment of efficiency. This study contributes to overcoming these limitations by introducing the stochastic frontier approach to assess the efficiency of the health care foodservice sector. It is superior to the traditional productivity approaches as it allows for the integrations of multiple inputs and outputs in evaluating relative efficiencies. The overall objective of the study was to determine the level of cost, technical and allocative efficiency in a sample of health care foodservice operations. More specifically, the objective was pursued by estimating stochastic production and cost frontiers models, which provided the basis for measuring technical (TE), allocative (AE) and cost efficiency (CE). The factors that significantly contribute to increasing inefficiency in health care foodservice operations were also identified. In this way, this study has policy implications because it not only provided empirical measures of different efficiency indices, but also identifies some key variables that are correlated with these indices. It goes beyond much of the published literature concerning efficiency because most research in the area of efficiency analysis focuses exclusively on the measurement of technical and cost efficiency. The stochastic frontier approach was tested in a cross sectional data set from a sample of 101 health care foodservice operations in Australia and the USA. Results showed that the models and all the parameters coefficients were plausible, significant and satisfy all theoretical requirements. Further, results also showed that the average cost, technical and cost efficiency were around 70 percent, 80 percent and 88 percent respectively. These figures suggest that substantial gains in output and/or decreases in cost can be attained if hospital foodservice operations were to improve their current performance. Finally, the results indicated that an increase in the level of manager’s experience and the level of manager’s education could have a positive impact on decreasing the level of inefficiency in health care foodservice operations.

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22

Ntayiya, Witness Sakumzi. "Evaluating the quality of care for sexually transmitted infections (STI) in 14 primary health care (PHC) facilities in Umjindi local municipality, Mpumalanga Province." Thesis, University of the Western Cape, 2004. http://etd.uwc.ac.za/index.php?module=etd&amp.

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The overall aim of this study was to evaluate quality of STI services in Umjindi local municipality. A concrete objective was to investigate the health system issues that may have a negative impact in the provision of quality STI service in the local municipality. These include accessibility of the STI services to the community, training of health workers in syndromic management, availability of necessary equipment and supplies for STI management, turn-around time for blood results and infrastructure of the facilities.

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23

Du, Wenjie (James). "EXAMINING THE INCREMENTAL EFFECTS OF PARTICIPANT SPORTING EVENTS IN PROMOTING ACTIVE LIVING: CREATING ACTIONABLE KNOWLEDGE TO TACKLE A PUBLIC HEALTH CRISIS." Diss., Temple University Libraries, 2017. http://cdm16002.contentdm.oclc.org/cdm/ref/collection/p245801coll10/id/428449.

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Tourism and Sport
Ph.D.
Using a theoretical synergy between the Psychological Continuum Model (PCM) and Behavioral Ecological Model (BEM), the current dissertation research provides empirical evidence to support that organized participant sporting events can play a significant role in building a healthier community. First, using a proprietary U.S. community-based panel data from 2008 to 2014, study 1 examines the incremental effects of participant sporting events (PSE) in promoting active living at the population level. Panel regression with an instrumental variable approach and Multigroup Latent Growth Curve Analysis were administered. The key findings included (1) these population-based interventions have the capacity to impact population health at the state level; (2) such an influence significantly varies across the United States contingent upon a state’s economic development and the geographical region to which a state belongs. In study 2, the Multilevel Mediation Analysis was conducted with a spatially clustered cross-sectional data in 2014. The findings revealed that the access to exercise opportunities at the state level represents the underlying mechanism through which various forms of participant sporting events have the ability to elicit positive effects on health with respects to mental health, physical health, and physical activity participation at the county level. The findings suggested that PSEs represent effective public health platform to create healthier communities through integrating physically active leisure into population’s everyday routines. Overall, empirical results also help us better understand the importance of effectively leveraging community sporting events to deliver required health benefits to the general public and create practical guidelines to inform policy formation on resource allocation.
Temple University--Theses

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24

Moreno, Argilés Pere. "Latent heat thermal energy storage units in HVAC systems for energy management." Doctoral thesis, Universitat de Lleida, 2014. http://hdl.handle.net/10803/288212.

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L'objectiu d'aquesta tesi és estudiar l'aplicació de tancs d'emmagatzematge d'energia tèrmica en una bomba de calor convencional. En aquesta tesi s'inclou un estudi experimental on dos tancs d'emmagatzematge d'energia són acoblats a una bomba de calor aigua-aigua amb l'objectiu d'emmagatzemar energia tèrmica per després utilitzar-la per cobrir la demanda de refrigeració d'un cubicle, produint un desplaçament de la corba de la demanda d'hores puntes a hores valls. En aquest estudi s'analitza el comportament tèrmic del tanc i es realitza una comparativa entre la utilització de PCM i aigua com a medis d'emmagatzematge d'energia tèrmica. En aquesta tesi també s'inclou una descripció de sistemes similar publicats a la literatura, un estudi teòric on es descriu un model matemàtic per simular la descàrrega del tanc i un anàlisi d'incerteses dels paràmetres d'entrada, i finalment, un estudi de corrosió de diferents metalls quan treballen en contacte amb PCM aptes per ser utilitzats en sistemes actius de climatització.
El objetivo de esta tesis es estudiar la aplicación de tanques de almacenamiento de energía térmica en una bomba de calor convencional. En esta tesis se incluye un estudio experimental en donde dos tanques de almacenamiento de energía son acoplados a una bomba de calor agua-agua con el objetivo de almacenar energía térmica para posteriormente utilizarla para cubrir la demanda de refrigeración de un cubículo, produciendo un desplazamiento de la curva de la demanda desde las horas punta a las horas valle. En este estudio se analiza el comportamiento térmico del tanque i se realiza una comparativa entre la utilización de PCM i agua como medios de almacenamiento térmico. En esta tesis también se incluye una descripción de sistemas similares publicados en la literatura, un estudio teórico en donde se describe un modelo matemático para simular la descarga del tanque y un análisis de incertidumbres de los parámetros de entrada, y finalmente, un estudio de corrosión de diferentes metales cuando éstos trabajan en contacto con PCM aptos para ser utilizados en sistemas activos de climatización.
The objective of this thesis is to study the application of thermal energy storage tanks (TES) in a standard heat pump. This thesis includes an experimental study where two TES tanks are coupled to a water-to-water heat pump in order to accumulate thermal energy for later use. The system is used for shifting the cooling load of a small house-like cubicle, shifting the load from on-peak to off-peak periods. The thermal behaviour of the TES tank and a comparison between PCM and water as energy storage medium are evaluated in this study. Moreover, this thesis also includes a state-of-the-art review of similar studies found in the literature, a theoretical study where a mathematical model is developed to predict the thermal behaviour of the TES tank during discharging process, an uncertainties analysis of the input parameters, and finally, a corrosion study of different metals when work in contact with potential PCM to be used in HVAC systems.

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25

Yaser, Hussnain A. "Novel System Design For Residential Heating And Cooling Load Shift Using PCM Filled Plate Heat Exchanger And Auxiliaries For Economic Benefit And Demand Side Management." University of Cincinnati / OhioLINK, 2014. http://rave.ohiolink.edu/etdc/view?acc_num=ucin1397234246.

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26

Green, Craig Elkton. "Composite thermal capacitors for transient thermal management of multicore microprocessors." Diss., Georgia Institute of Technology, 2012. http://hdl.handle.net/1853/44772.

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While 3D stacked multi-processor technology offers the potential for significant computing advantages, these architectures also face the significant challenge of small, localized hotspots with very large heat fluxes due to the placement of asymmetric cores, heterogeneous devices and performance driven layouts. In this thesis, a new thermal management solution is introduced that seeks to maximize the performance of microprocessors with dynamically managed power profiles. To mitigate the non-uniformities in chip temperature profiles resulting from the dynamic power maps, solid-liquid phase change materials (PCMs) with an embedded heat spreader network are strategically positioned near localized hotspots, resulting in a large increase in the local thermal capacitance in these problematic areas. Theoretical analysis shows that the increase in local thermal capacitance results in an almost twenty-fold increase in the time that a thermally constrained core can operate before a power gating or core migration event is required. Coupled to the PCMs are solid state coolers (SSCs) that serve as a means for fast regeneration of the PCMs during the cool down periods associated with throttling events. Using this combined PCM/SSC approach allows for devices that operate with the desirable combination of low throttling frequency and large overall core duty cycles, thus maximizing computational throughput. The impact of the thermophysical properties of the PCM on the device operating characteristics has been investigated from first principles in order to better inform the PCM selection or design process. Complementary to the theoretical characterization of the proposed thermal solution, a prototype device called a "Composite Thermal Capacitor (CTC)" that monolithically integrates micro heaters, PCMs and a spreader matrix into a Si test chip was fabricated and tested to validate the efficacy of the concept. A prototype CTC was shown to increase allowable device operating times by over 7X and address heat fluxes of up to ~395 W/cm2. Various methods for regenerating the CTC have been investigated, including air, liquid, and solid state cooling, and operational duty cycles of over 60% have been demonstrated.

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27

Isouard, Godfrey. "A total quality management approach to appropriate clinical laboratory test utilisation in acute myocardial infarction." Thesis, [Milperra, N.S.W. : Teh Author], 1996. http://handle.uws.edu.au:8081/1959.7/670.

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The first goal of this investigation was to undertake a non-equivalent quasi-experimental design to test the effect of a total Quality management (TQM) approach to improve the appropriateness of clinical laboratory test utilisation in the management of early acute myocardial infarction (AMI). The study was conducted at 2 public hospitals in Sydney over a 30 month period, and in 2 stages- pre and post TQM intervention. Using specifically a Continuous Quality Improvement (CQI) FOCUS-PDCA model, a multidisciplinary team was empowered to make appropriate changes in order to improve a variety of problem areas that affected the total pathology service. Improvement was directed at the total system of pathology testing, not just test ordering. It was observed that the introduction of a TQM environment had provided a more committed, integrated and motivated clinical care effort towards improving the appropriateness of test ordering. Such team efforts were accompanied by demonstrated customer satisfaction at various aspects of the laboratory service and further benefits to patient care. Patient care benefited greatly from the highly significant changes towards more appropriate timing of blood collections for cardiac enzyme testing. Other improvements included overall improvements to the turnaround time of test results, reductions in specimen delivery delays, more appropriate use of clinical laboratory tests, a streamlined distribution of printed reports and marked improvements in communication between staff involved in the process of test ordering. Of major importance was the finding that CQI strategies resulted in substantial savings of 23.0% of the overall cost of pathology services. Adoption of the TQM approach appears to be a strategy worthy of exploration by laboratory directors and health administrators interested in improving patient care while at the same time reducing expenditure.

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28

Shaneb, Omar Ali. "Optimisation and operation of residential micro combined heat and power (μCHP) systems". Thesis, Durham University, 2012. http://etheses.dur.ac.uk/4432/.

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In response to growing concerns regarding global warming and climate change, reduction of CO2 emissions becomes a priority for many countries, especially the developed ones such as the UK. Residential applications are considered among the most important areas for substantial reduction of CO2 emissions because they represent a major part of the total consumed energy in those countries. For instance, in the UK, residential applications are currently accountable for about 150 Mt CO2 emissions, which represents approximately 25% of the whole CO2 emissions [1-2]. In order to achieve a significant CO2 reduction, many strategies must be adopted in the policy of these countries. One of these strategies is to introduce micro combined heat and power (μCHP) systems into residential energy systems, since they offer several advantages over traditional systems. A significant amount of research has been carried out in this field; however, in terms of integrating such systems into residential energy systems, significant work is yet to be conducted. This is because of the complexity of these systems and their interdependency on many uncertain variables, energy demand of a house is a case in point. In order to achieve such integration, this research focuses on the optimisation and operation of μCHP systems in residential energy systems as essential steps towards integration of these systems, so it deals with the optimisation and operation of a μCHP system within a building taking into account that the system is grid-connected in order to export or import electricity in certain cases. A comprehensive review that summarises key points that outline the trend of previous research in this field has been carried out. The reviewed areas include: technologies used as residential μCHP units, modelling of the μCHP systems, sizing of μCHP systems and operation strategies used for such systems. To further this, a generic model for sizing of μCHP system’s components to meet different residential application has been developed by the author. Two different online operation strategies of residential μCHP systems, namely: an online linear programming optimiser (LPO) and a real time fuzzy logic operation strategy (FLOS) have been developed. The performance of the novel online operation strategies, in terms of their ability to reduce operation costs, has been evaluated. Both the LPO and the FLOS were found to have their advantages when compared with the traditional operation strategies of μCHP systems in terms of operation costs and CO2 emissions. This research should therefore be useful in informing design and operation decisions during developing and implementing μCHP technologies in residential applications, especially single dwellings.

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29

McGee, Seán. "Thermal energy management and chemical reaction investigation of micro-proton exchange membrane fuel cell and fuel cell system using finite element modelling." Thesis, KTH, Kraft- och värmeteknologi, 2015. http://urn.kb.se/resolve?urn=urn:nbn:se:kth:diva-173001.

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Fuel cell systems are becoming more commonplace as a power generation method and are being researched, developed, and explored for commercial use, including portable fuel cells that appear in laptops, phones, and of course, chargers. This thesis examines a model constructed on inspiration from the myFC PowerTrekk, a portable fuel cell charger, using COMSOL Multiphysics, a finite element analysis software. As an educational tool and in the form of zero-dimensional, two-dimensional, and three-dimensional models, an investigation was completed into the geometric construction, air conditions and compositions, and product materials with a best case scenario completed that summarizes the results identified. On the basis of the results of this research, it can be concluded that polyoximetylen and high-density polyethylene were considered as possible materials for the majority of the product, though a more thorough investigation is needed. Air flow of above 10 m/s, air water vapour mass fraction below 50% and initial temperature between 308K and 298K was considered in this best scenario. Suggestions on future expansions to this project are also given in the conclusion.

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30

Hedlund, Niclas. "Tyst kunskap och produktdatasystem vid medicinteknisk tillverkning : Pilotstudie av system för produktdatahantering och kartläggning av den tysta kunskapen vid Nationellt respirationscetrum, NRC." Thesis, Uppsala University, Department of Information Technology, 2009. http://urn.kb.se/resolve?urn=urn:nbn:se:uu:diva-126753.

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This thesis looks at two sides of the same coin: how to support the production and future development at a specialist medical technology department at Danderyd Hospital. The two sides are; a pilot study of a product management system (PDM) and an interview based study on the characteristics of the silent knowledge of the technicians. The department (National respiratory centre, NRC) is facing retirement of several key employees.

The technical study shows that the success of an implementation is largely dependent on the users’ prior knowledge and use of a 3D Computer aided design system (CAD).The system itself is shown to fulfill the Lifecycle requirement of tracking the products (mostly tracheostomy tubes) but without a CAD centered workflow, some substantial education and preferably some new recruits, an implementation of the PDM system will fail. The author recommends development of the current “low-tech” system of MS Excel and Access rather than redistribute the dependency from technician towards a complex, commercial software and its vendor.

The analysis of the technicians’ silent knowledge with the newly developed method, epithet for silent knowledge (ETK), shows that the longer employment time:

the more differentiated technicians become in describing their work,
practical knowledge are regarded higher and
the social and collective problem solving factors of the work becomes more important.

Typically, it is shown that a new employee should preferably enjoy problem solving, being pragmatic and social as well as having some prior education or work experience in a CAD and/or a PDM system.

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31

Hedwig, Michael. "Effektives Kraftstoffdampfmanagement für PKW durch multiphysikalische Modellierung eines mit Phasenwechselmaterialien optimierten Adsorbers." Doctoral thesis, Saechsische Landesbibliothek- Staats- und Universitaetsbibliothek Dresden, 2016. http://nbn-resolving.de/urn:nbn:de:bsz:14-qucosa-201981.

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Анотація:

Das Kraftstoffdampfmanagement in PKW dient der Reduzierung von Kraftstoffdampfemissionen und umfasst deren Entstehung im Tank, sowie Verarbeitung im Adsorber. Im Hinblick auf eine effektive Emissionsreduzierung erfolgt in dieser Arbeit die Entwicklung eines multiphysikalischen Berechnungsmodells, das die Erschließung der Kraftstoffdampfmenge im Tank sowie der Adsorbercharakteristik erlaubt. Gleichzeitig wird eine Methode zur thermischen Adsorberoptimierung durch Phasenwechselmaterialien (PCM) vorgestellt. Letztere nutzen für ihren fest/flüssig-Phasenübergang im Adsorber umgesetzte Prozesswärmen und können damit dessen Arbeitskapazität erhöhen. Die Modellierung der tankinternen Kraftstoffdampfproduktion erfolgt basierend auf der Berechnung des Dampf-Flüssigkeit-Gleichgewichtes von Mehrstoffsystemen mit realen Fluidmodellen. Zudem wird eine thermodynamische Datenbank erstellt, die es erlaubt, reale ottomotorische Kraftstoffgemische durch Modellkraftstoffsysteme mit deutlich reduzierter Komponentenanzahl abzubilden. Es wird ein detailliertes nicht-isothermes 2D-rotationssymmetrisches Mehrkammeradsorbermodell für kompressible Fluidgemische entwickelt, das die temperaturabhängige Polyschichtsorption in porösen Festbetten wiedergibt und direkt über transiente Randbedingungen mit der instationären Kraftstoffverdampfung im Tank gekoppelt ist. Darin berücksichtigt sind unter anderem anisotrope Wärme- und Stofftransportprozesse innerhalb der Festbetten sowie Randeffekte infolge einer nicht-linearen Porositätsverteilung. Zwischen den Sorptionskammern wird eine dünnwandige Aluminium-Trennwand aus makroverkapseltem PCM integriert, die zur Temperierung der umliegenden Festbetten dient. Hierzu wird auf Basis einer diskontinuierlichen Form der Enthalpy-Porosity-Methode der nicht-isotherme Phasenwechsel im Latentwärmespeicher unter Berücksichtigung der konvektiven Schmelzbewegung modelliert und in Ort und Zeit mit dem Adsorbermodell gekoppelt. Das daraus resultierende partielle Differenzialgleichungssystem wird örtlich über eine Finite-Elemente-Methode und bzgl. der Zeit in Form eines impliziten Mehrschrittverfahrens diskretisiert. Die entsprechende numerische Lösung erfolgt mit Hilfe eines automatisch gedämpften Newton-Verfahrens. Anhand des Adsorbermodells lässt sich der Einfluss von Randeffekten auf das Ad- und Desorptionsverhalten erschließen, die eine Abhängigkeit von der Festbettgeometrie und des temperaturabhängigen Beladungszustandes zeigen. Diese Sorptionsprozesse werden durch experimentelle Versuchs- reihen an einem hierzu entwickelten Adsorber-Prototyp validiert. Als Ergebnis der numerischen Simulation anwendungsrelevanter Prüfzyklen zur Adsorber-Typisierung resultiert durch den Einsatz von PCM eine Effizienzsteigerung in der Arbeitskapazität des Adsorbers von ca. 14 − 19 %. Zudem kann gezeigt werden, dass auch in Betriebszuständen ohne latenten Phasenwechsel im PCM infolge der konvektiven Bewegung der Schmelze die Sorptionsfähigkeit teilweise um mehr als 11 % ansteigt. Gleichzeitig ist im Vergleich zu der einfachen Vergrößerung des chemischen Sorptionsspeichers der Effekt einer Festbetttemperierung durch PCM partiell bis zu 10 % höher. Durch das einfache Substituieren der klassischen Kunststofftrennwände zwischen den Festbetten durch dünnwandige PCM-Kammern wird die Kraftstoffdampfnachbehandlung ohne relevante Gewichts- und Volumenzunahme des Adsorbers bedeutend verbessert.

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32

CHEN, MING-HSIANG, and 陳銘祥. "Study on Missile Maintenance Technology of Prognostic and Health Management (PHM)." Thesis, 2017. http://ndltd.ncl.edu.tw/handle/3j6pp7.

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Анотація:

碩士
國立高雄第一科技大學
資訊管理系碩士專班
106
The missile is the high price weapons, since the produce to the decommission has a long service life. The current maintenance mode, whether it is time-triggered cycle of maintenance or event-triggered fault repair, have their shortcomings. In order to solve the problem between the two present study was to investigate the way the literature, offered to Open Service Architecture (OSA-CBM, Open System Architecture - Condition Based Maintenance) for the infrastructure in the understanding of Prognostics and properly manage the required infrastructure, Technology and construction conditions, combined with the actual requirements of the national missile maintenance and maintenance, put forward a complete set of service architecture and processes to Logistics Engineering reliability, maintenance, support and productivity of the four major elements of the assessment The Institute proposed the architecture process, combined with Delphi method to invite experts to implement in-depth interviews, make equipment failure prediction and proper management technology into the current operating mode requirements, key and resource analysis, and put forward the appropriate way and related recommendations for system development or logistical unit in charge of policy, as a follow-up development and future work related references.

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33

CHANG, SHANG-JEN, and 張尚仁. "A Study of Health Assessment and Fault Diagnosis for UH-60M Oil Cooler Bearing Using Prognostics and Health Management (PHM)." Thesis, 2019. http://ndltd.ncl.edu.tw/handle/c9q442.

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碩士
逢甲大學
智能製造與工程管理碩士在職學位學程
107
Aircraft as important transportation requires the highest flight safety. Successful implementation of faults monitoring, diagnosis and failures prognosis to safety critical components require predictive maintenance. The development of predictive maintenance has become mainstream in the aviation industry. This thesis considers an oil cooler bearing of the UH-60M helicopter and adopts the Prognostics and Healthy Management (PHM) methodology for bearing fault detection and failure prognosis. The PHM methodology including data pre-processing, feature extraction and selection; training/testing modeling, bearing fault diagnosis and prog-nostic modeling are discussed in the current study. Three batches of dataset acquired from three helicopters were used for health assessment and fault diagnosis of the helicopter. A fleet analysis was performed to verify the accuracy of the model. Experimental results indicated that the accuracy of fault diagnosis achieves 100% by using support vector machine (SVM) algorithm. PHM is a potential methodolo-gy for health assessment and fault diagnosis of the oil cooler bearing of the helicopter.

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34

Chen, Tsung-Jung, and 陳聰榮. "The Study of PCM Role In Quality and Safety-Health Management System under Construction for Engineering Projects." Thesis, 2002. http://ndltd.ncl.edu.tw/handle/30250730367101699751.

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碩士
國立臺灣科技大學
營建工程系
90
Under the impact of competitive international market because of entering WTO, public works or private construction trades would not survive if we still manage the works by means of traditional engineering management. In order to help the owners complete the constructions under limited resources, this research adopted Professional Construction Management ( PCM ) as the leadership of the construction team, and intends to negotiate and integrate the construction work systematically. The quality as well as the safe and healthy systems are established according to the QA management outlines of Administrative Institution Public Construction Quality Management. According to the spirits of the goal management and performance management and the ideas of the process management, the professional project construction engineering management system is set up to elevate the availability of professional construction supervision. The PM cases were first studied and documents and the opinions of practice field and scholars were then combined to set up the PCM construction supervision system of municipal public works. The system includes drawing up control and management system of construction activities, the critical works, the memorandums, the possible difficulties and the feasible control method. Furthermore, the process and the memorandum are integrated to set up the supervision flowcharts. For the conveniences of application, The charts and checklist tables are frequently used.

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35

Yen-Phi, Vo Thi [Verfasser]. "Quantitative microbial risk assessment for faecal management : health consequences in the Mekong Delta, Vietnam / vorgelegt von Vo Thi Yen-Phi." 2010. http://d-nb.info/1011700301/34.

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36

Vinh, Do Thanh, and 杯成永. "Research on Setting up a Project for Management Information System at the Department of Public Health in Phu Tho Province." Thesis, 2009. http://ndltd.ncl.edu.tw/handle/50973531361830051612.

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碩士
樹德科技大學
資訊管理研究所
97
In recent years, thanks to the development of information technology as well as its applications, information system management has been applied in a variety of fields. Its role is becoming more and more important. As shown from the fact, an effective information system is considered as a major factor to improve management activities. In Phu Tho Department of Public Health particularly, the operations related to information exchange as well as administrative management are currently performed in a very traditional way (in the form of incoming and outgoing documents). Therefore, it is necessary to computerize those operations for better management efficiency. This study describes the information system model applied in the Phu Tho Department of Public Health. After designing the system, in order to ensure the success of its implementation, two surveys were conduct for the purpose of checking the current situation of information technology infrastructure as well as the level and ability of staff and officers. These surveys were delivered directly to staff and officers in all divisions/hospitals/health centers/organization directly under phu Tho Department of Public Health. The result showed that in general, department did build a basic infrastructure to ensure the success of system implementations. Most of the unit equip computer system, 50% set up LAN network and high-speed internet connection. However, no divisions or units have designed its own website yet; and also many staff and officers can use computer but few exploited information via the internet or use technology applications.

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Mlcek, Susan Huhana E. "Paucity management models in community welfare service delivery." Thesis, 2008. http://handle.uws.edu.au:8081/1959.7/33647.

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The juxtaposition of doing ‘more with less’, and ‘being privileged to be a community welfare worker’ gives some indication of the anomalies present in how community welfare work is conceived and manifested. The original contribution of this thesis is to provide further knowledge and understanding of the nature, level and extent of paucity management models to inform the way that community welfare services are delivered in rural communities. Paucity management relates to the way that managers identify and utilise strategies to counter the anomaly of possessing a deep philosophical underpinning in the value of community work, with the lack of means to meet all the needs and expectations of community members. Fifteen managers from the Central West Region of New South Wales in Australia were asked to share work narratives about the way their activities contributed to sustaining their communities. The research confirms yet again that community services are delivered strategically in spite of, or because of, a resource poor environment that is mainly punctuated by the non-availability of ever-decreasing funds. New ways of seeking resources has resulted in managers and workers navigating competing priorities at ground level, with trying to balance the tensions implicit in a directive provider-purchaser work dynamic that has seen the evolvement of the hybrid government organisation. This qualitative research used a phenomenographic approach to collect the managers’ stories. Data collection methods included individual interviews, focus group discussions, as well as further consultative communication. A complex theoretical framework, incorporating ideas from paucity management, aspects of structuration, and chaos/ complexity, was used to analyse the data through a structure of awareness of variation in the managers’ experiences. The findings show that community welfare managers do work in a resource poor environment, do acknowledge the presence of paucity management, and do address the limit-situations of service delivery through different, but complimentary, paucity management models that are creative, pragmatic, communicatively competent, and ‘auto-managed’. Their combined narrative gives a clearer understanding of the style of management that the managers used, as well as some of the strategies that contributed to ‘chameleon qualities’ of management.

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38

Thompson, Julia Mary. "Patient and nurse collaboration in decision-making concerning long-term management of a newly formed colostomy." Thesis, 1997. http://handle.uws.edu.au:8081/1959.7/307.

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This study included three projects which investigated aspects of decision-making in a nursing context. The specific decision studied concerned selection of a long term management strategy for use by a patient with a newly fashioned colostomy. Literature reviewed reveals debate about the extent to which patients should participate in decisions about their health care, but ongoing work using the Autonomy Preference Index provides an argument for partnerships in decision-making between patients and health care professionals. This research contributed to the knowledge base in stomal therapy nursing, decision theory, collaborative practice in nusing, assessment of patient satisfaction and health communication theory. The clinical implications and applications of the findings are far reaching because of the pervasiveness of patient decision-making in nursing practice

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39

Halcomb, Elizabeth. "Carving a niche for Australian practice nurses in chronic heart failure management." Thesis, 2005. http://handle.uws.edu.au:8081/1959.7/444969.

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Chronic and complex conditions are a significant concern within contemporary health care systems. The ageing population and improvements in survival from acute cardiac illness have seen an increasing incidence of heart failure (HF). Heart failure represents a significant burden on both the individual and the wider community. Despite effective pharmacotherapy and established evidence-based management guidelines, the overall prognosis from HR is poor. The complexity of the disease process and the highly developed evidence-base makes HR an excellent exemplar for the management of a range of chronic conditions. Studies undertaken as part of the 'Carving a niche for Australian practice nurses' project have led to the development of a model of care that integrates the role of the practice nurse with those of other health care providers to improve outcomes for people with chronic and complex conditions. Whilst the model of care developed from these studies requires empirical testing to validate its utility, it is currently being incorporated in clinical planning and ongoing pragmatic research. The systematic, sequential derivation of data from the 'Carving a niche for Australian practice nurses' project will inform the development of primary care and provide a conceptual framework for future intervention studies in Australian general practice.

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Kaczan, Robert. "‘It’s (not) all in the mind’: PhD students’ experiences, well-being, and mindfulness." Thesis, 2015. https://vuir.vu.edu.au/33056/.

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Although undertaking a PhD provides great opportunities for intellectual challenges and benefits, students also experience high levels of stress and attrition within the degree. It is therefore important to better understand the needs of students and how to support them in order to improve their experience, increase well-being, and support better academic outcomes. This research conducted two studies: the first explores what supports and hinders the well-being and academic functioning of PhD students at one Victorian university; and the second—because stress is a large feature of PhD students’ lives—examines the potential of a brief mindfulness-based intervention (brief MBI) to provide benefits to students. This intervention is a modified and substantially shorter version of the mindfulness-based stress reduction (MBSR) program which was shortened from 8 weeks (27 hours) to 4 weeks (6 hours). This research used constructivist grounded theory as the strategy of inquiry and in-depth semi-structured interviews to achieve the aim of exploring subjective experiences, with participants interviewed at both one and four months post-intervention. Overall, Study 1 found that the needs of PhD students are best understood through an ecological perspective, that is, that the areas important to their well-being and academic functioning fall within and across individual, interpersonal, institutional, and structural, material, and social levels. Included in these areas are the needs for personal and academic growth, personal and academic competence, rest and rejuvenation, social and intellectual integration, and material and cohort specific supports. Further, achieving a balance across these areas of well-being and academic functioning represents an ideal student experience which promotes higher levels of satisfaction. Study 2 found that the brief MBI provided some benefits to these students including stress reduction, increased positive affect, and improved academic functioning at the one month interview. However, at four months, many of these benefits were not sustained and only a few participants continued to practise techniques from the program. A brief MBI, therefore, has some value in supporting students but requires further modifications to sustain benefits and be of greater help to this population.

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Zulu, Margaret Thandeka. "An evaluation of the management of rural ward-based primary health care : a case study of Uthukela District Municipality in KwaZulu-Natal." Thesis, 2016. http://hdl.handle.net/10321/1558.

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Submitted in fulfillment of the requirements for the degree of Doctor in Public Management, School of Public Management and Economics, Durban University of Technology, Durban, South Africa, 2016.
The shortage of staff in hospitals resulted in the overcrowding of outpatients departments (OPDs) and long waiting times. The problems of the current health care system include the lack of access to transportation and high transport fees which cause delays in health seeking behaviours by patients or them resorting to traditional medicine in their neighbourhood. To alleviate the above issues, the new Primary Health Care (PHC) approach provides health care at a ward based and household level through community care giver (CCGs) and outreach teams. The study evaluated the management of rural ward-based primary health care in the UThukela District Municipality (UDM). The study intended to evaluate current performance systems in order to provide effective and efficient PHC; identify the role of the operational manager (OM) in the provision of PHC; and identify the factors affecting the performance of CCGs. A mixed methods approach was used amongst 368 CCGs and 17 OMs. Data was collected from CCGs using questionnaires while an interview schedule was used to collect data from OMs. The study showed that the performance management systems currently being used were not providing the desired performance management outputs. There were no performance bonuses to recognise best performing staff and therefore no increase in performance. The study also showed a significant relationship between the management of referrals and participation in the activities of PHC outreach teams. The clinic was not regularly giving feedback to the respondents and also not consistently conducting performance reviews. The findings indicated that OMs were playing various roles in the provision of PHC, namely policy and strategy implementation; leadership and governance; clinical care; allocation of resources; clinic budget management; supply chain management; and writing clinic reports. The extent of the allocation of resources to the wards varied from 43% for medicines and equipment to 31% for financial resources and only 18% for human resources. More than 95% of the CCGs viewed the availability of transport, resources, training and the provision of a stipend to be strong enabling factors for them to perform their work. Respondents indicated that monitoring and evaluation was done through reporting, performance reviews, feedback and supervision. The findings indicated that ward-based outreach teams are crucial in the delivery of PHC services in rural municipal wards within the Operation Sukuma Sakhe programme. Lack of management and supervisory support contribute to high rates of dissatisfaction amongst CCGs, as well as poor quality of work for community caregivers. There is a need for the Department of Health (DoH) to invest in the ward-based outreach teams (WBOTs) and allocate CCG budgets within the ward-based outreach teams. The study recommended that a review of monitoring and evaluation policy is required to clearly state the tools, activities and benefits of the implementation of the M & E performance management systems. The use of point-of-care technology by the WBOTs should be strengthened especially in deep rural wards. Therefore, biomedical technology will enhance point-of-care diagnosis, for instance, rapid home test kits for HIV diagnosis and pregnancy tests. The KwaZulu-Natal DoH should fast-track development of the sub-districts in order strengthen service delivery at a local level with top management ensuring development of OMs and PHC Supervisors in order to increase the level of competence and thereby improve service delivery at the PHC facilities. Another recommendation was to strengthen implementation of Operation Sukuma Sakhe (OSS) where the war room and the ward committee increase commitment to designing community-specific interventions with the engagement of community structures and government departments and local municipality through social planning, social action and locality development. Therefore, the results of the study should also influence the formulation of policies, programmes, methods and interventions which will enable UThukela District Municipality to improve health outcomes.
D

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42

Demers, Maxime. "Analyse de la logique d’intervention d’une adaptation québécoise d’un modèle de soins centré sur le patient appuyé par un dossier médical personnel dans les suivis pédiatriques au sein d’un groupe de médecine de famille." Thèse, 2014. http://hdl.handle.net/1866/12090.

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43

Hedwig, Michael. "Effektives Kraftstoffdampfmanagement für PKW durch multiphysikalische Modellierung eines mit Phasenwechselmaterialien optimierten Adsorbers: Effektives Kraftstoffdampfmanagement für PKW durch multiphysikalische Modellierung eines mit Phasenwechselmaterialien optimierten Adsorbers." Doctoral thesis, 2015. https://tud.qucosa.de/id/qucosa%3A29450.

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Das Kraftstoffdampfmanagement in PKW dient der Reduzierung von Kraftstoffdampfemissionen und umfasst deren Entstehung im Tank, sowie Verarbeitung im Adsorber. Im Hinblick auf eine effektive Emissionsreduzierung erfolgt in dieser Arbeit die Entwicklung eines multiphysikalischen Berechnungsmodells, das die Erschließung der Kraftstoffdampfmenge im Tank sowie der Adsorbercharakteristik erlaubt. Gleichzeitig wird eine Methode zur thermischen Adsorberoptimierung durch Phasenwechselmaterialien (PCM) vorgestellt. Letztere nutzen für ihren fest/flüssig-Phasenübergang im Adsorber umgesetzte Prozesswärmen und können damit dessen Arbeitskapazität erhöhen. Die Modellierung der tankinternen Kraftstoffdampfproduktion erfolgt basierend auf der Berechnung des Dampf-Flüssigkeit-Gleichgewichtes von Mehrstoffsystemen mit realen Fluidmodellen. Zudem wird eine thermodynamische Datenbank erstellt, die es erlaubt, reale ottomotorische Kraftstoffgemische durch Modellkraftstoffsysteme mit deutlich reduzierter Komponentenanzahl abzubilden. Es wird ein detailliertes nicht-isothermes 2D-rotationssymmetrisches Mehrkammeradsorbermodell für kompressible Fluidgemische entwickelt, das die temperaturabhängige Polyschichtsorption in porösen Festbetten wiedergibt und direkt über transiente Randbedingungen mit der instationären Kraftstoffverdampfung im Tank gekoppelt ist. Darin berücksichtigt sind unter anderem anisotrope Wärme- und Stofftransportprozesse innerhalb der Festbetten sowie Randeffekte infolge einer nicht-linearen Porositätsverteilung. Zwischen den Sorptionskammern wird eine dünnwandige Aluminium-Trennwand aus makroverkapseltem PCM integriert, die zur Temperierung der umliegenden Festbetten dient. Hierzu wird auf Basis einer diskontinuierlichen Form der Enthalpy-Porosity-Methode der nicht-isotherme Phasenwechsel im Latentwärmespeicher unter Berücksichtigung der konvektiven Schmelzbewegung modelliert und in Ort und Zeit mit dem Adsorbermodell gekoppelt. Das daraus resultierende partielle Differenzialgleichungssystem wird örtlich über eine Finite-Elemente-Methode und bzgl. der Zeit in Form eines impliziten Mehrschrittverfahrens diskretisiert. Die entsprechende numerische Lösung erfolgt mit Hilfe eines automatisch gedämpften Newton-Verfahrens. Anhand des Adsorbermodells lässt sich der Einfluss von Randeffekten auf das Ad- und Desorptionsverhalten erschließen, die eine Abhängigkeit von der Festbettgeometrie und des temperaturabhängigen Beladungszustandes zeigen. Diese Sorptionsprozesse werden durch experimentelle Versuchs- reihen an einem hierzu entwickelten Adsorber-Prototyp validiert. Als Ergebnis der numerischen Simulation anwendungsrelevanter Prüfzyklen zur Adsorber-Typisierung resultiert durch den Einsatz von PCM eine Effizienzsteigerung in der Arbeitskapazität des Adsorbers von ca. 14 − 19 %. Zudem kann gezeigt werden, dass auch in Betriebszuständen ohne latenten Phasenwechsel im PCM infolge der konvektiven Bewegung der Schmelze die Sorptionsfähigkeit teilweise um mehr als 11 % ansteigt. Gleichzeitig ist im Vergleich zu der einfachen Vergrößerung des chemischen Sorptionsspeichers der Effekt einer Festbetttemperierung durch PCM partiell bis zu 10 % höher. Durch das einfache Substituieren der klassischen Kunststofftrennwände zwischen den Festbetten durch dünnwandige PCM-Kammern wird die Kraftstoffdampfnachbehandlung ohne relevante Gewichts- und Volumenzunahme des Adsorbers bedeutend verbessert.

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