The project was aimed at describing the mixing phenomena relevant for both safety analysis, particularly in steam line break and boron dilution scenarios, and mixing phenomena of interest for economical operation and the structural integrity. Measurement data from a set of mixing experiments, gained by using advanced measurement techniques with enhanced resolution in time and space help to improve the basic understanding of turbulent mixing and to provide data for Computational Fluid Dynamics (CFD) code validation. Slug mixing tests simulating the start-up of the first main circulation pump are performed with two 1:5 scaled facilities: The Rossendorf coolant mixing model ROCOM and the VATTENFALL test facility, modelling a German Konvoi type and a Westinghouse type three-loop PWR, respectively. Additional data on slug mixing in a VVER-1000 type reactor gained at a 1:5 scaled metal mock-up at EDO Gidropress are provided. Experimental results on mixing of fluids with density differences obtained at ROCOM and the FORTUM PTS test facility are made available. Concerning mixing phenomena of interest for operational issues and thermal fatigue, flow distribution data available from commissioning tests (Sizewell-B for PWRs, Loviisa and Paks for VVERs) are used together with the data from the ROCOM facility as a basis for the flow distribution studies. The test matrix on flow distribution and steady state mixing performed at ROCOM comprises experiments with various combinations of running pumps and various mass flow rates in the working loops. Computational fluid dynamics calculations are accomplished for selected experiments with two different CFD codes (CFX-5, FLUENT). Best practice guidelines (BPG) are applied in all CFD work when choosing computational grid, time step, turbulence models, modelling of internal geometry, boundary conditions, numerical schemes and convergence criteria. The BPG contain a set of systematic procedures for quantifying and reducing numerical errors. The knowledge of these numerical errors is a prerequisite for the proper judgement of model errors. The strategy of code validation based on the BPG and a matrix of CFD code validation calculations have been elaborated. Besides of the benchmark cases, additional experiments were calculated by new partners and observers, joining the project later. Based on the "best practice solutions", conclusions on the applicability of CFD for turbulent mixing problems in PWR were drawn and recommendations on CFD modelling were given. The high importance of proper grid generation was outlined. In general, second order discretization schemes should be used to minimise numerical diffusion. First order schemes can provide physically wrong results. With optimised "production meshes" reasonable results were obtained, but due to the complex geometry of the flow domains, no fully grid independent solutions were achieved. Therefore, with respect to turbulence models, no final conclusions can be given. However, first order turbulence models like K-e or SST K-w are suitable for momentum driven slug mixing. For buoyancy driven mixing (PTS scenarios), Reynolds stress models provide better results.

The project was aimed at describing the mixing phenomena relevant for both safety analysis, particularly in steam line break and boron dilution scenarios, and mixing phenomena of interest for economical operation and the structural integrity. Measurement data from a set of mixing experiments, gained by using advanced measurement techniques with enhanced resolution in time and space help to improve the basic understanding of turbulent mixing and to provide data for Computational Fluid Dynamics (CFD) code validation. Slug mixing tests simulating the start-up of the first main circulation pump are performed with two 1:5 scaled facilities: The Rossendorf coolant mixing model ROCOM and the VATTENFALL test facility, modelling a German Konvoi type and a Westinghouse type three-loop PWR, respectively. Additional data on slug mixing in a VVER-1000 type reactor gained at a 1:5 scaled metal mock-up at EDO Gidropress are provided. Experimental results on mixing of fluids with density differences obtained at ROCOM and the FORTUM PTS test facility are made available. Concerning mixing phenomena of interest for operational issues and thermal fatigue, flow distribution data available from commissioning tests (Sizewell-B for PWRs, Loviisa and Paks for VVERs) are used together with the data from the ROCOM facility as a basis for the flow distribution studies. The test matrix on flow distribution and steady state mixing performed at ROCOM comprises experiments with various combinations of running pumps and various mass flow rates in the working loops. Computational fluid dynamics calculations are accomplished for selected experiments with two different CFD codes (CFX-5, FLUENT). Best practice guidelines (BPG) are applied in all CFD work when choosing computational grid, time step, turbulence models, modelling of internal geometry, boundary conditions, numerical schemes and convergence criteria. The BPG contain a set of systematic procedures for quantifying and reducing numerical errors. The knowledge of these numerical errors is a prerequisite for the proper judgement of model errors. The strategy of code validation based on the BPG and a matrix of CFD code validation calculations have been elaborated. Besides of the benchmark cases, additional experiments were calculated by new partners and observers, joining the project later. Based on the "best practice solutions", conclusions on the applicability of CFD for turbulent mixing problems in PWR were drawn and recommendations on CFD modelling were given. The high importance of proper grid generation was outlined. In general, second order discretization schemes should be used to minimise numerical diffusion. First order schemes can provide physically wrong results. With optimised "production meshes" reasonable results were obtained, but due to the complex geometry of the flow domains, no fully grid independent solutions were achieved. Therefore, with respect to turbulence models, no final conclusions can be given. However, first order turbulence models like K-e or SST K-w are suitable for momentum driven slug mixing. For buoyancy driven mixing (PTS scenarios), Reynolds stress models provide better results.

An important aspect in the process of architectural design is the testing of solution alternatives in order to evaluate them on their appropriateness within the context of the design problem. Computational Fluid Dynamics (CFD) analysis is one of the approaches that have gained popularity in the testing of architectural design solutions especially for purposes of evaluating the performance of natural ventilation strategies in buildings. Natural ventilation strategies can reduce the energy consumption in buildings while ensuring the good health and wellbeing of the occupants. In order for natural ventilation strategies to perform as intended, a number of factors interact and these factors must be carefully analysed. CFD simulations provide an affordable platform for such analyses to be undertaken. Traditionally, these simulations have largely followed the direction of Best Practice Guidelines (BPGs) for quality control. These guidelines are built around certain simplifications due to the high computational cost of CFD modelling. However, while the computational cost has increasingly fallen and is predicted to continue to drop, the BPGs have largely remained without significant updates. The need to develop a CFD simulation framework that leverages the contemporary and anticipates the future computational cost and capacity can, therefore, not be overemphasised. When conducting CFD simulations during the process of architectural design, the variability of the wind flow field including the wind direction and its velocity constitute an important input parameter. Presently, however, in many simulations, the wind direction is largely used in a steady state manner. It is assumed that the direction of flow downwind of a meteorological station remains constant. This assumption may potentially compromise the integrity of CFD modelling as in reality, the wind flow field is bound to be dynamic from place to place. In order to improve the accuracy of the CFD simulations for architectural design, it is therefore necessary to adequately account for this variability. This study was a two-pronged investigation with the ultimate objective of improving the accuracy of the CFD simulations that are used in the architectural design process, particularly for the design and analysis of natural ventilation strategies. Firstly, a framework for integrated meso-scale and building scale CFD simulations was developed. Secondly, the newly developed framework was then implemented by deploying it to study the variability of the wind flow field between a reference meteorological station, the Virginia Tech Airport, and a selected localized building scale site on the Virginia Tech campus. The findings confirmed that the wind flow field varies from place to place and showed that the newly developed framework was able to capture this variation, ultimately, generating a wind flow field characterization representative of the conditions prevalent at the localized building site. This framework can be particularly useful when undertaking de-coupled CFD simulations to design and analyse natural ventilation strategies in the building design process. / Doctor of Philosophy / The use of natural ventilation strategies in building design has been identified as one viable pathway toward minimizing energy consumption in buildings. Natural ventilation can also reduce the prevalence of the Sick Building Syndrome (SBS) and enhance the productivity of building occupants. This research study sought to develop a framework that can improve the usage of Computational Fluid Dynamics (CFD) analyses in the architectural design process for purposes of enhancing the efficiency of natural ventilation strategies in buildings. CFD is a branch of computational physics that studies the behaviour of fluids as they move from one point to another. The usage of CFD analyses in architectural design requires the input of wind environment data such as direction and velocity. Presently, this data is obtained from a weather station and there is an assumption that this data remains the same even for a building site located at a considerable distance away from the weather station. This potentially compromises the accuracy of the CFD analyses as studies have shown that due to a number of factors such the urban built form, vegetation, terrain and others, the wind environment is bound to vary from one point to another. This study sought to develop a framework that quantifies this variation and provides a way for translating the wind data obtained from a weather station to data that more accurately characterizes a local building site. With this accurate site wind data, the CFD analyses can then provide more meaningful insights into the use of natural ventilation in the process of architectural design. This newly developed framework was deployed on a study site at Virginia Tech. The findings showed that the framework was able to demonstrate that the wind flow field varies from one place to another and it also provided a way to capture this variation, ultimately, generating a wind flow field characterization that was more representative of the local conditions.

Cette étude avait pour but d’évaluer, à partir d’un processus de co-construction avec les personnes concernées, dans un contexte de 1ère ligne, la mise en application d’interventions infirmières inspirées du Guide des meilleures pratiques de soins pour les endeuillés (GMPSE) auprès d’un couple ayant vécu une perte périnatale au cours des six dernier mois. Un devis de recherche d’étude de cas basé sur la démarche d’évaluation de la quatrième génération de Guba et Lincoln (1989) a été utilisé. Une infirmière expérimentée auprès des familles endeuillées, s’est inspirée de la guidance du GMPSE pour intervenir auprès d’un couple lors de cinq rencontres thérapeutiques, dont quatre ont été précédées d’une entrevue avec les personnes concernées . Ces entrevues ont permis à ces personnes d’identifier ensemble les interventions les plus utiles et les moins utiles. Le verbatim des rencontres et entrevues ont été enregistrées et transcrites à des fins d’analyses qualitatives, Les résultats de ces analyses font ressortir la pertinence des interventions inspirées du GMPSE et l’apport spécifique de la pratique infirmière auprès de la population visée. Il appert que la sensibilisation des décideurs et des cliniciens aux enjeux des personnes endeuilles soit nécessaire pour favoriser l’implantation du Guide dans les milieux de soins. Enfin, une meilleure appropriation du GMPSE est recommandée autant dans le cadre de la formation, que de la recherche et de la pratique en sciences infirmières. / The purpose of this study was to evaluate from a constructivist perspective, partnering with the stakeholders , the usefulness of nursing interventions inspired from The Best Practice Guidelines in Bereavement Care (BPGBC) in a first line context, during the follow up a couple whom had experienced a prenatal lost in the last six months. A case study design was used along with The Fourth Evaluation’s methodological approach designed by Guba and Lincoln (1989). An experienced nurse in the care of bereaved families, used the BPGBC to guide her interventions in five therapeutic meetings with the couple, followed by four interviews with the stakeholders. The interventions considered the most helpful and the less useful were identified. The gathering of the data and their analysis followed an interactive and ongoing process. The results support the pertinence of the nursing interventions inspired from the BPGBC, as well as the specific contribution of the nursing profession in the bereavement work. Implementing the BPGBC becomes a realistic goal when the managers and the clinical professionals are made aware of the issues encompassed by the grieving population. The nursing profession could incorporate the BPGBC in its training curriculum, in the research field and in the care offered to the bereaved population in different care settings.

Cette étude avait pour but d’évaluer, à partir d’un processus de co-construction avec les personnes concernées, dans un contexte de 1ère ligne, la mise en application d’interventions infirmières inspirées du Guide des meilleures pratiques de soins pour les endeuillés (GMPSE) auprès d’un couple ayant vécu une perte périnatale au cours des six dernier mois. Un devis de recherche d’étude de cas basé sur la démarche d’évaluation de la quatrième génération de Guba et Lincoln (1989) a été utilisé. Une infirmière expérimentée auprès des familles endeuillées, s’est inspirée de la guidance du GMPSE pour intervenir auprès d’un couple lors de cinq rencontres thérapeutiques, dont quatre ont été précédées d’une entrevue avec les personnes concernées . Ces entrevues ont permis à ces personnes d’identifier ensemble les interventions les plus utiles et les moins utiles. Le verbatim des rencontres et entrevues ont été enregistrées et transcrites à des fins d’analyses qualitatives, Les résultats de ces analyses font ressortir la pertinence des interventions inspirées du GMPSE et l’apport spécifique de la pratique infirmière auprès de la population visée. Il appert que la sensibilisation des décideurs et des cliniciens aux enjeux des personnes endeuilles soit nécessaire pour favoriser l’implantation du Guide dans les milieux de soins. Enfin, une meilleure appropriation du GMPSE est recommandée autant dans le cadre de la formation, que de la recherche et de la pratique en sciences infirmières. / The purpose of this study was to evaluate from a constructivist perspective, partnering with the stakeholders , the usefulness of nursing interventions inspired from The Best Practice Guidelines in Bereavement Care (BPGBC) in a first line context, during the follow up a couple whom had experienced a prenatal lost in the last six months. A case study design was used along with The Fourth Evaluation’s methodological approach designed by Guba and Lincoln (1989). An experienced nurse in the care of bereaved families, used the BPGBC to guide her interventions in five therapeutic meetings with the couple, followed by four interviews with the stakeholders. The interventions considered the most helpful and the less useful were identified. The gathering of the data and their analysis followed an interactive and ongoing process. The results support the pertinence of the nursing interventions inspired from the BPGBC, as well as the specific contribution of the nursing profession in the bereavement work. Implementing the BPGBC becomes a realistic goal when the managers and the clinical professionals are made aware of the issues encompassed by the grieving population. The nursing profession could incorporate the BPGBC in its training curriculum, in the research field and in the care offered to the bereaved population in different care settings.

No description available.

South Africa is a water-scarce country and over the years, the quality of water resources has deteriorated due to poor effluent discharge, agricultural, industrial, mining and human activities. The major contributing factors of poorly-treated or inadequately treated wastewater may be attributed to: (a) the poor design and construction of wastewater treatment plants; (b) lack of qualified process controllers; (c) non-compliance with applicable legislation; (d) lack of proper monitoring; and (e) management issues with regard to wastewater treatment plants. Water quality is important as many communities depend on water resources for their daily activities and livelihood. There is a need therefore to build and manage wastewater treatment plants effectively as they have an impact on water quality. Wastewater treatment plants in South Africa are regulated by the Constitution of the Republic of South Africa, 1996, the National Environmental Management Act 107 of 1998, the National Water Act 36 of 1998, the Water Services Act 108 of 1997, Provincial legislation, Municipal by-laws and other Government policies applicable to Local Government. Chapter 7 of the Constitution inter alia, provides that Local Government has the duty to provide a safe and healthy environment to its community in a sustainable manner. Schedule 4B of the Constitution imposes the function of delivering water, sanitation and wastewater treatment services on Municipalities. This responsibility rests on District Municipalities but may be performed by a Local Municipality if the district municipality lacks the capacity to do so. Although Local Government has the right to govern on its own initiative the affairs of its communities, it needs support and monitoring from other spheres of Government (National and Provincial) to ensure the delivery of wastewater treatment services in a sustainable manner. In this study, Ba-Phalaborwa Local Municipality is used as an example of a Municipality in the Limpopo Province faced with challenges related to the operation and management of its wastewater treatment plant. This study aims to determine who should be responsible for the regulation of wastewater treatment plants in Ba-Phalaborwa Local Municipality area in order to ensure service delivery to communities in a sustainable manner. In order to deal with the challenges experienced by Local Government in dealing with wastewater treatment plants, the study considers Best Practice Guidelines and external service delivery mechanisms, specifically in the form of Public-Private Partnerships. The study concludes with recommendations based on Best Practice Guidelines which Municipalities can use to avoid wastewater pollution and proposes management mechanisms in managing a Public-Private Partnership effectively in order to ensure that they provide service delivery in a sustainable manner. / LLM (Environmental Law and Governance), North-West University, Potchefstroom Campus, 2014

South Africa is a water-scarce country and over the years, the quality of water resources has deteriorated due to poor effluent discharge, agricultural, industrial, mining and human activities. The major contributing factors of poorly-treated or inadequately treated wastewater may be attributed to: (a) the poor design and construction of wastewater treatment plants; (b) lack of qualified process controllers; (c) non-compliance with applicable legislation; (d) lack of proper monitoring; and (e) management issues with regard to wastewater treatment plants. Water quality is important as many communities depend on water resources for their daily activities and livelihood. There is a need therefore to build and manage wastewater treatment plants effectively as they have an impact on water quality. Wastewater treatment plants in South Africa are regulated by the Constitution of the Republic of South Africa, 1996, the National Environmental Management Act 107 of 1998, the National Water Act 36 of 1998, the Water Services Act 108 of 1997, Provincial legislation, Municipal by-laws and other Government policies applicable to Local Government. Chapter 7 of the Constitution inter alia, provides that Local Government has the duty to provide a safe and healthy environment to its community in a sustainable manner. Schedule 4B of the Constitution imposes the function of delivering water, sanitation and wastewater treatment services on Municipalities. This responsibility rests on District Municipalities but may be performed by a Local Municipality if the district municipality lacks the capacity to do so. Although Local Government has the right to govern on its own initiative the affairs of its communities, it needs support and monitoring from other spheres of Government (National and Provincial) to ensure the delivery of wastewater treatment services in a sustainable manner. In this study, Ba-Phalaborwa Local Municipality is used as an example of a Municipality in the Limpopo Province faced with challenges related to the operation and management of its wastewater treatment plant. This study aims to determine who should be responsible for the regulation of wastewater treatment plants in Ba-Phalaborwa Local Municipality area in order to ensure service delivery to communities in a sustainable manner. In order to deal with the challenges experienced by Local Government in dealing with wastewater treatment plants, the study considers Best Practice Guidelines and external service delivery mechanisms, specifically in the form of Public-Private Partnerships. The study concludes with recommendations based on Best Practice Guidelines which Municipalities can use to avoid wastewater pollution and proposes management mechanisms in managing a Public-Private Partnership effectively in order to ensure that they provide service delivery in a sustainable manner. / LLM (Environmental Law and Governance), North-West University, Potchefstroom Campus, 2014

With the introduction of universal newborn hearing screening (UNHS) the need for quality early hearing intervention (EHI) services became critical. Screening is but the avenue to EHI services. Without appropriate intervention infants with hearing loss are at risk for language delay which might subsequently adversely influence academic success and vocational choices later on in life. The numerous socio-economic, cultural and healthcare barriers associated with developing countries such as South Africa, do not negate or diminish the need for optimal outcomes for infants with hearing loss through quality EHI services. The principle of quality EHI services, aligned with international standards, is endorsed by the HPCSA (2003: 2). In order to assure quality in EHI, service evaluation is critical. The necessary first step when evaluating service provision is to measure current service delivery. The main aim of this study was to determine whether South African audiologists provide EHI and support services aligned with international professional best practice to infants following the diagnosis of hearing loss. The first part of this study reviews the evidence available in EHI. The guidelines derived from the international evidence were stated as benchmarks against which South African EHI services were measured. These benchmarks were categorised using the so-called six M variation categories. These categories are: Man, machine (equipment), method (systemaric procedures), measurements, material (amplification devices) and Mother Nature. During the empirical research a descriptive design was followed comprising of questionnaire surveys to audiologists in different working sectors rendering EHI services to infants with hearing loss. The questionnaire survey explored the nature and scope of the EHI services offered to infants with hearing loss with regard to all the components (categorised in the six M categories) of the EHI programme of 40 South African audiologists. The results of this study indicate that respondents often do not use evidence-based measurements or methods during EHI services. Results suggest that undergraduate training in areas regarding the selection and fitting of amplification to infants with hearing loss is often inadequate (>20 respondents indicated that they are not trained). Evidence-based measurements are not typically performed when fitting amplification to infants (29 respondents do not perform probe-microphone or elctroacoustic measurements). Many respondents indicated that they do not have the necessary equipment to do these measurements. EHI services often (50% of respondents) do not provide A/R directly, but refer to other team members. From the results there seems to be significant delays in the rendering of EHI services to infants with hearing loss. Financial constraints of the family of the infants, accessibility problems, as well as a lack of infant support from their families often influence the EHI programmes of respondents. The implications of this study were discussed. Recommendations include the development of South African guidelines, aligned with international guidelines but taking into account the challenges posed by the unique South African context. Other recommendations include: Centres of excellence, relevant continuing education programmes and the evaluation of undergraduate training programmes. / Dissertation (M (Communication Pathology))--University of Pretoria, 2006. / Speech-Language Pathology and Audiology / M (Communication Pathology) / unrestricted

The purpose of the study was to develop best practice guidelines to prevent permanent hearing loss associated with the management of multi-drug resistant tuberculosis (MDR-TB) through raised awareness and monitoring. The Human Immunodeficiency Virus (HIV) and MDR-TB are global public health problems requiring urgent scale-up of treatment services. Irreversible sensorineural hearing loss (SNHL) is one of the adverse drug reactions of the current World Health Organization (WHO) recommended MDR-TB chemotherapy fuelling another public health problem, that disabling hearing loss, which is the second highest contributor of Years Lived with Disability (YLD) according to the World Health Report (2003). Expansion of MDR-TB treatment threatens to increase incidence of SNHL unless there is urgent implementation of intervention towards preservation of hearing for patients on treatment. This empirical study determined and documented the incidence of SNHL in HIV positive and HIV negative patients on MDR-TB treatment, the risk factors for SNHL, from the time treatment initiation to SNHL. Based on the findings, developed and improved the understanding of best practice guidelines for monitoring and prevention of MDR-TB treatment-related SNHL. The empirical study recruited a cohort of 173 patients with normal hearing status, after diagnosis with MDR-TB and enrolled on MDR-TB therapy over thirteen month period. Patients in the cohort received monthly hearing sensitivity testing during the intensive MDR-TB therapy when injectable aminoglycoside antibiotics are part of the treatment regimen. The three study endpoints included completion of the eight-month intensive treatment phase without developing hearing loss, development incident hearing loss or loss to follow up. Data was analysed using STATA statistical software and summarised using frequencies, means, proportions, and rates. The study documented incidence of SNHL, time to hearing loss and risk factors for hearing loss. Recommendations to prevent and monitor hearing loss are made based on the the study findings. / Health Studies / D. Litt. et Phil. (Health Studies)