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  • About
  • The Global ETD Search service is a free service for researchers to find electronic theses and dissertations. This service is provided by the Networked Digital Library of Theses and Dissertations.
    Our metadata is collected from universities around the world. If you manage a university/consortium/country archive and want to be added, details can be found on the NDLTD website.
101

Reshaping an Enduring Sense of Self: The Process of Recovery from a First Episode of Schizophrenia

Romano, Donna M. 10 July 2009 (has links)
Although many advances in the treatment of schizophrenia have been made over the past decade, little is known about the process of recovery from a first episode of schizophrenia (FES). To date, the study of recovery in the field of mental health has focused on long-term mental illness. This in depth qualitative study drew upon Charmaz’s (1990) constructivist grounded theory methodology to address the following questions: How do individuals who have experienced a FES describe their process of recovery? How does an identified individual (e.g. friend, family member, teacher, or clinician) describe their role during the participant’s process of recovery, and their perception of the recovery process? Ten primary participants (who self-identified as recovering from a FES) had two interviews; in addition, there was a one-time interview with a secondary participant, for a total of 30 interviews. Data collection sources included participant semi-structured interviews, participant selected personal objects that symbolized their recovery, and clinical records. The results provide a substantive theory of the process of recovery from a FES. The emergent process of recovery model for these participants is comprised of the following phases: ‘Lives prior to the illness’, ‘Lives interrupted: Encountering the illness’, ‘Engaging in services and supports’, ‘Re-engaging in life’, ‘Envisioning the future’; and the core category, ‘Re-shaping an enduring sense of self,’ that occurred through all phases. A prominent distinctive feature of this model is that participants’ enduring sense of self were reshaped versus reconstructed throughout their recovery. The emergent model of recovery from a FES is unique, and as such, provides implications for clinical care, future research, and policy development specifically for these young people and their families.
102

Reservoir simulation studies for coupled CO₂ sequestration and enhanced oil recovery

Ghomian, Yousef, January 1900 (has links)
Thesis (Ph. D.)--University of Texas at Austin, 2008. / Vita. Includes bibliographical references.
103

Recharge dynamics of a perched phreatic aquifer

Ketchum, J. Neil. January 1900 (has links)
Thesis (M.S.)--West Virginia University, 1998. / Title from document title page. "December 15, 1998." Document formatted into pages; contains ix, 119 p. : ill. (some col.), maps. Includes abstract. Includes bibliographical references (p. 109-115).
104

Economic analysis of secondary and enhanced oil recovery techniques in Wyoming

Kara, Erdal. January 2008 (has links)
Thesis (Ph.D.)--University of Wyoming, 2008. / Title from PDF title page (viewed on June 24, 2009). Includes bibliographical references (p. 120-127).
105

Self-stigma, decisional capacity and personal recovery in psychosis

Lynch, Helen January 2017 (has links)
Introduction: This research portfolio set out to examine service user defined recovery in psychosis. A systematic review was undertaken to examine the evidence-base for the effectiveness of psychosocial interventions on personal recovery, empowerment and other recovery-related outcomes. An empirical study was conducted to examine the relationships between self-stigma, decisional capacity for treatment and personal recovery in service users with psychosis. Methods: A review of published literature identified ten randomised controlled trials investigating the effects of psychosocial interventions on personal recovery. A narrative synthesis was reported for findings relating to primary and secondary outcomes, and standardised effect sizes were calculated to quantify within-group change from pre-to post-intervention and follow-up. Studies were assessed for risk of bias. The empirical study recruited twenty-four participants with diagnoses of non-affective psychosis. Semi-structured interviews and self-report measures were administered to assess self-stigma, decisional capacity for treatment, psychopathology, emotional distress and personal recovery. Results: A small number of studies found that recovery-focused psychosocial interventions improved personal recovery. There were more consistent effects on psychiatric symptoms, functioning and depression. The empirical study found that self-stigma and personal recovery were associated with each other. Large effect sizes were found for the associations between self-stigma and symptoms. These associations persisted when controlling for personal recovery scores. Understanding of treatment was predicted by excitement symptoms, but no other prediction model emerged for decisional capacity. Conclusion: Taken together, the systematic review and empirical project support service user definitions of recovery which highlight the role of psychosocial factors. The systematic review found some evidence for the role of recovery-focused psychosocial interventions in improving personal recovery. Further research is needed so that interventions specifically targeting the processes in personal recovery can be developed. The findings from the empirical project suggested that interventions designed to overcome self-stigmatising beliefs and reduce emotional distress are likely to improve personal recovery outcomes in psychosis. More research is needed to develop a broader conceptualisation of decisional capacity in psychosis, to support the active participation of service users in their recovery journey.
106

Enhanced recovery after liver surgery

Hughes, Michael John January 2016 (has links)
Introduction Liver resection offers curative treatment to a number of malignant conditions. It has traditionally been associated with poor post-operative outcomes. More recently a mortality rate of less than five per cent has become established but morbidity remains high. Enhanced Recovery After Surgery (ERAS) has become established practice in a number of surgical specialties and has shown improvement in post-operative outcomes. ERAS has been introduced for liver resection however practice is less well established and liver surgery has several complexities that need to be accommodated in order to optimise post-operative care. The following thesis aims to identify areas that require clarification and investigate peri-operative care components to establish optimum practice. Methods Systematic review and meta-analysis were performed to identify areas that required clarification and were lacking in sufficient evidence to guide practice. A randomised controlled trial was performed to compare established areas of practice. Prospective observational studies were performed when exploratory investigation was required. Retrospective analysis of a prospectively collected database was performed to identify risk factors for post-operative morbidity. Patients included in the above trials underwent liver resection at the Royal Infirmary of Edinburgh, UK, between December 2012 and August 2014. Results Post-operative analgesia after liver resection was identified as being an area that was controversial. Continuous wound infiltration was shown to offer improved recovery times when compared to epidural with no significant associated disadvantages. After retrospective review of 603 liver resections, extended resection was observed to be associated with high morbidity rates. It was hypothesised that post-operative nutritional requirements might be higher in these patients. This was not found to be the case but post-operative energy requirements were found to be difficult to predict after liver resection, suggesting the benefits of real-time monitoring of energy expenditure. Finally acetaminophen metabolism was suspected of being altered after major resection. An observational study suggested that despite altered metabolism, glutathione deficiency was not observed after major resection and so liver volume was not a contra-indication to acetaminophen administration. Summary Liver resection offers a complex set of conditions on which to base an enhanced recovery protocol. Current ERAS literature does not completely address these issues. This thesis has investigated several aspects of care unique to liver surgery in an attempt to optimise peri-operative care and improve post-operative outcome after liver surgery.
107

Resilience of Cloud Networking Services for Large Scale Outages

Pourvali, Mahsa 06 April 2017 (has links)
Cloud infrastructure services are enabling organizations and enterprises to outsource a wide range of computing, storage, and networking needs to external service providers. These offerings make extensive use of underlying network virtualization, i.e., virtual network (VN) embedding, techniques to provision and interconnect customized storage/computing resource pools across large network substrates. However, as cloud-based services continue to gain traction, there is a growing need to address a range of resiliency concerns, particularly with regards to large-scale outages. These conditions can be triggered by events such as natural disasters, malicious man-made attacks, and even cascading power failures. Overall, a wide range of studies have looked at network virtualization survivability, with most efforts focusing on pre-fault protection strategies to set aside backup datacenter and network bandwidth resources. These contributions include single node/link failure schemes as well as recent studies on correlated multi-failure \disaster" recovery schemes. However, pre-fault provisioning is very resource-intensive and imposes high costs for clients. Moreover this approach cannot guarantee recovery under generalized multi-failure conditions. Although post-fault restoration (remapping) schemes have also been studied, the effectiveness of these methods is constrained by the scale of infrastructure damage. As a result there is a pressing need to investigate longer-term post-fault infrastructure repair strategies to minimize VN service disruption. However this is a largely unexplored area and requires specialized consideration as damaged infrastructures will likely be repaired in a time-staged, incremental manner, i.e., progressive recovery. Furthermore, more specialized multicast VN (MVN) services are also being used to support a range of content distribution and real-time streaming needs over cloud-based infrastructures. In general, these one-to-many services impose more challenging requirements in terms of geographic coverage, delay, delay variation, and reliability. Now some recent studies have looked at MVN embedding and survivability design. In particular, the latter contributions cover both pre-fault protection and post-fault restoration methods, and also include some multi-failure recovery techniques. Nevertheless, there are no known efforts that incorporate risk vulnerabilities into the MVN embedding process. Indeed, there is a strong need to develop such methods in order to reduce the impact of large-scale outages, and this remains an open topic area. In light of the above, this dissertation develops some novel solutions to further improve the resiliency of the network virtualization services in the presence of large outages. Foremost, new multi-stage (progressive) infrastructure repair strategies are proposed to improve the post-fault recovery of VN services. These contributions include advanced simulated annealing metaheuristics as well as more scalable polynomial-time heuristic algorithms. Furthermore, enhanced \risk-aware" mapping solutions are also developed to achieve more reliable multicast (MVN) embedding, providing a further basis to develop more specialized repair strategies in the future. The performance of these various solutions is also evaluated extensively using custom-developed simulation models.
108

Using turbine expanders to recover exothermic reaction heat for the combined production of power and chemicals

Perold, Jaco 30 November 2005 (has links)
Many reactions carried out in the chemical industry are exothermic. The heat liberated by the reaction is often transferred to another medium such as steam by heat exchange. This heat can then be used elsewhere or be used to generate power via a steam cycle. In this work the focus is on another method of reaction heat recovery. When an exothermic reaction is conducted at elevated pressures, a turbine expander can be placed directly behind the reactor. The hot, high-pressure product gas from the reactor can then be expanded in the turbine. During the expansion process the physical energy of the product gas is converted to kinetic energy (or electricity if the turbine is connected to a generator). Three chemical processes were studied to determine the feasibility of turbine integration into the processes. They are ethylene oxide production, phthalic anhydride production and the hydrodealkylation of alkylaromatic compounds. The chosen processes differ in terms of reactor operation, reactant conversion as well as the presence or absence of recycle loops. Simulation models were developed for the mentioned processes with the process simulator Aspen Plus®. Results from the simulations show that, without the turbine, the processes require power from external sources. They can however operate independently from external power sources when a turbine is present. Excess power can be exported or used for electricity generation. It is therefore feasible• to incorporate turbine expansion units in all the processes considered. The operating conditions of some unit operations have to be changed to accommodate the turbine expander. With the additional product namely power, a re-evaluation of all the operating conditions and tradeoffs in the process is necessary. Further investigation into the impact of turbine integration on the optimal operating conditions of the process is therefore recommended. Traditional definitions used to evaluate the performance of a process generating or consuming power, were found to be inadequate for use in processes where power and chemicals are produced together. New performance parameters are required for the evaluation of processes where power and chemicals are produced simultaneously. An exergy analysis was performed for one of the cases. This analysis method provides insight as to where thermodynamic losses occur in a process. The exergy analysis was useful to quantify the losses occurring in an isenthalpic expansion valve, and the savings obtained by replacing such a valve with an expansion turbine. / Dissertation (MEng (Chemical Engineering))--University of Pretoria, 2006. / Chemical Engineering / unrestricted
109

Modeling and Analysis of Synchronization Schemes for the TDMA Based Satellite Communication System

Wang, Chong January 2012 (has links)
No description available.
110

Polyurethane-Polybenzoxazine Based Shape Memory Polymers

Erden, Numan 23 December 2009 (has links)
No description available.

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