Erosion and deposition in gas turbine engines are functions of particle/wall interactions and the Coefficient of Restitution (COR) is a fundamental property of these interactions. COR depends on impact velocity, angle of impact, temperature, particle composition, and wall material. In the first study, a novel Particle Tracking Velocimetry (PTV) / Computational Fluid Dynamics (CFD) hybrid method for measuring COR has been developed which is simple, cost-effective, and robust. A Laser-Camera system is used in the Virginia Tech Aerothermal Rig to measure microparticles velocity. The method solves for particle impact velocity at the surface by numerical methods. The methodology presented here characterizes a difficult problem by a combination of established techniques, PTV and CFD, which have not been used in this capacity before. The current study characterizes the fundamental behavior of sand at different impact angles. Two sizes of Arizona Road Dust (ARD) and one size of Glass beads are impacted on to 304-Stainless Steel. The particles are entrained into a free jet of 27m/s at room temperature. Mean results compare favorably with trends established in literature. This technique to measure COR of microparticle sand will help develop a computational model and serve as a baseline for further measurements at elevated, engine representative air and wall temperatures. In the second study, ARD is injected into a hot flow field at temperatures of 533oK, 866oK, and 1073oK to measure the effects of high temperature on particle rebound. The results are compared with baseline measurements at ambient temperature made in the VT Aerothermal Rig, as well as previously published literature. The effects of increasing temperature and velocity led to a 12% average reduction in total COR at 533oK (47m/s), a 15% average reduction at 866oK (77m/s), and a 16% average reduction at 1073oK (102m/s) compared with ambient results. From these results it is shown that a power law relationship may not conclusively fit the COR vs temperature/velocity trend at oblique angles of impact. The decrease in COR appeared to be almost entirely a result of increased velocity that resulted from heating the flow. / Ph. D.

Economic impacts of research that developed Rosette virus-resistant peanut in Uganda are estimated, including the impacts on poverty. The impacts of technology on the cost of production at the household level are determined. This information is used to compute aggregate benefits in an economic surplus model. A probit model is used to identify the determinants of adoption using household data. Information regarding the determinants of adoption is combined with impacts of technology on the cost of production to identify income changes for adopting households. Foster-Greer-Thorbecke poverty measures are used to project changes in poverty for households that adopt. It is estimated that the poverty rate will decline by 1.3 percent as a result of the research. / Master of Science

Yes / AHRC, University of Bradford and the Higher Education Innovation Fund.

Throughout human history, conflicts have profoundly impacted economic development, causing severe damage to infrastructure, disrupting economic activities, deterring investment, and straining government finances. However, most studies on this topic focus on either individual countries or specific conflict events, despite the availability of rich panel data. This study aims to explore the impact of conflicts on a country’s income, specifically GDP per capita, in a panel setting. It employs a two-way fixed effect (TWFE) counterfactual estimation method instead of a simple TWFE estimation to assess the causal effects of conflict. Our findings suggest that conflicts significantly reduce GDP per capita on average compared to countries without any conflict. This comprehensive analysis underscores the critical need for effective conflict resolution strategies to mitigate these economic impacts.

The dissertation at hand presents the findings that have emerged from the research intervention in a case study, Gpi Group, conducted with a general objective to propose an approach that would assist an organisation in developing tailored indicators for social impact measurement. Three studies administered within the framework of this interventionist research pursue the aim: i) to explore conditions informing the substantive-symbolic adoption of sustainability agenda; ii) to reveal factors that hinder calculative practices from ensuring accountability of technology companies in the healthcare system; and iii) given the restricted direct stakeholder engagement, to design an approach or methodological tool for the impact measurement indicators. The research has been conducted in the interventionist research tradition, whereby the researcher collaborates with organisational members to solve real-world problems and contribute to scientific knowledge. In this work, the identified problem pertains to the limitations of conventional indicators in measuring implications arising from the Gpi Group’s operations that are borne by final beneficiaries. The company offers a wide range of technological solutions and health booking services for the healthcare sector. However, despite the considerable importance of final beneficiaries, namely medical professionals and patients, they remain underrepresented in materiality, which has motivated this research. The first chapter outlines emerging nuances, power dynamics, and internal tensions when the organisation decides to commit to the sustainability agenda and formalise corresponding standards. By triangulating data from corporate documents, interviews, and survey, and further interpreting them through the lens of Bourdieu’s field theory, it has been revealed that substantive-symbolic adoption of sustainability standards depends on the power dynamics that enable a shared meaning of sustainability and accordingly shape individuals’ habitus. The second chapter explores whether existing calculative practices for impact can ensure the accountability of technology companies operating in the healthcare sector. By identifying commonly used indicators from extant scientific research and non-academic reports and further critically scrutinising them with organisational members of the case study, a limited practical validity of calculative practices is revealed for technology companies. Pragmatic constructivism applied to the interview analysis points to the topoi mismatch and insufficient addressing of a practical validity condition across all dimensions of the actor’s reality construction, which led to the abstract and theoretical indicators. The third chapter describes in detail the indicator-building approach for social impact measurement and the process of integrating derived indicators into Gpi Group’s materiality assessment. Materiality, which is a highly contested concept in the literature, has been examined from a pragmatic stance in this chapter. The application of this approach to the organisational setting, where it is prohibited to involve final beneficiaries by virtue of regulations and ethical concerns, has enabled deriving 21 indicators composing four major materiality topics.

The ultimate goal of this dissertation was to better understand what the Apollo sample collection tells us about the impact history of the Moon. My main research tool is a computer code called Cratered Terrain Evolution Model (CTEM). CTEM is a Monte Carlo landscape evolution code developed to model a planetary surface subjected to impacts. While the main effect of impact cratering that CTEM simulates is elevation changes of the landscape through the excavation process of craters and the deposition of ejecta, I worked to extend the capabilities of the code to study problems in material transport. As impact cratering is a dominant process on the surface of Moon, the stratigraphy of lunar geology is thought to be composed of stacks of impact-generated ejecta layers. Each individual impact generates ejecta that is sourced from varying depths of the subsurface. This ejecta contains a rich abundance of material containing information, including composition and datable impact products, such as impact glasses. The extensions to the CTEM code that I developed allows me to track all ejecta generated during a simulation and model the complex history of the lunar regolith.

L'énergie-bois qui entrent à Kinshasa, arrivent par camion, camionnette, tracteur. Ils proviennent essentiellement des provinces du Bas-Congo et du Bandundu, et ce, par route et/ou par rail. Le transport de ces combustibles est une activité très rémunératrice. Il y a deux types de circuits de distribution de l'énergie-bois. Il s'agit des circuits direct et indirect. Les acteurs de ces circuits sont les producteurs, les grossistes, les détaillants et les consommateurs. Dans la VPK, la répartition des points de vente et des dépôts est inégale. Au fil du temps, une augmentation croissante des prix, qui entraîne de sérieux problèmes de survie pour certains ménages, est enregistrée. Le dépositaire et les détaillants en tirent un revenu moyen mensuel supérieur à celui des hauts fonctionnaires de l'administration publique de la RDC. Dans la VPK, presque tous les habitants consomment le charbon de bois (CB); une personne brûle 33 kg de bois de chauffe (BC) par mois et 11 kg de CB par mois, ce qui engendre des problèmes de survie dans les ménages. Les besoins en combustibles ligneux sont de 4 000 000 et 1 320 000 tonnes respectivement de BC et de CB dans la VPK. Cette consommation, nous la qualifions d'hécatombe écologique car le déboisement provoqué par les besoins annuels en combustible ligneux à Kinshasa sont très élevés soit 40 907 666 tonnes de BC et 1 320 000 tonnes de CB. Ces besoins engendrent une dégradation annuelle de formations végétales qui correspondrait aux données suivantes : concernant le BC, la forêt claire, la forêt claire muhuluteuse, la forêt dense sèche sont déboisées annuellement, respectivement de 204,5 km2, 272,7 km2 et 511,3 km2; et pour le CB la déforestation annuelle est de 485,2 km2 de forêt claire, une superficie équivalente pour la forêt claire muhuluteuse et 942,8 km2 de forêt dense. La forêt dégradée, quant à elle, est amputée annuellement de 58 439 ha pour les besoins en BC et de 18 857 ha pour les besoins en CB. En réalité de tels rythmes annuels représenteraient rapidement une catastrophe pour les écosystèmes forestiers de la région de Kinshasa et ceux du Bas-Congo et de Bandundu qui, d'ailleurs, subissent déjà cette agression de manière croissante depuis plus d'un siècle. Mais hélas, sans aucun programme de suivi et de soutien à l'aménagement forestier, il est quasi impossible de contrer ou de réduire la vitesse avec laquelle se fait le déboisement de la ceinture verte de Kinshasa ainsi que des régions environnantes. La croissance chaotique de la ville de Kinshasa et le processus d'occupation des sols se font d'une manière anarchique, incontrôlée et sans normes urbanistiques. La ville a explosé et s'est étalée vite. Les constructions occupent non seulement la plaine, les vallées et lits des cours d'eau, mais aussi les versants et sommets des collines en y enlevant la couverture végétale. Outre cet aspect, la ville a son système d'égout détruit et est déficiente du point de vue des infrastructures. Cette situation engendre non seulement des inondations le long des cours d'eau dans la ville, mais aussi l’érosion et l'ensablement de lits de rivières. Plusieurs études et reportages confirment qu'il ya plus de 600 têtes de ravins qui cisaillent la capitale de la RDC. ______________________________________________________________________________ MOTS-CLÉS DE L’AUTEUR : Combustibles ligneux, charbon de bois, bois de chauffage, déforestation

An enhanced approach for the impact analysis is presented. Impact analyses play an important role in future research analysis as part of the scenario techniques in the strategic management field. Nowadays, they are also applied for the description of mutual relationships of tangible and intangible resources in organisations. The new method is based on currently existing methods using a cross impact matrix and overcomes some of their drawbacks. Indirect impacts are considered together with their impact strengths. A modification of the impact matrix is not necessary. Simple examples show that the new method leads to more reasonable and stable results than the existing methods. The new method shall help analysing the complexity of social systems in a more reliable way.

This thesis examines the social and environmental impacts that have resulted from the construction and operation of the Channel Tunnel. Nord-Pas de Calais, Kent, France, Britain and Europe were all affected through the establishment of the Channel Tunnel. Three sections make up the body of this thesis: i. context and theory ii. social, environmental and economic impacts associated with the construction and operation of the tunnel iii. acknowledgement of the impacts that this development has had on the European Union. This study draws from an extensive body of literature in identifying and examining the issues that preceded and followed this development. The social and environmental impacts associated with public opposition, environmental impacts, land possession, soil disposal, environmental disturbance, water pollution, noise disturbance, energy consumption, water contamination, fire safety and asylum seekers remain the principal discussion points identifiable throughout this piece. These issues are largely concentrated on the areas of Nord-Pas de Calais and Kent, although they are infiltrating the wider European Union in a number of ways. The social and environmental impact assessments conducted prior to the construction of the of the Channel Tunnel proved to be tools that helped ensure that the bodies driving the development were made accountable for the impacts that arose. These processes also facilitated public involvement through public consultation in the development of social and environmental impact assessment. Early identification and recognition of the social and environmental issues identified by these reports led to a more comprehensive approach to project design, construction and operation.

The aim of this study was to identify difficulties experienced by caregivers of children orphaned by HIV/AIDS. The aim was achieved through the following objectives: investigate the family background of caregivers of AIDS orphans; investigate the general emotional impact of caring for AIDS orphans on caregivers; investigate the health impact of caring for AIDS orphans on caregivers; investigate the extent of financial impact of caring for AIDS orphans on caregivers; investigate the impact of caring for AIDS orphans on the social life of caregivers; to make recommendations so as to assist in helping caregivers. A literature review and the qualitative empirical research method were used to achieve the aim and thus, the objectives stated above. The literature review revealed the following difficulties experienced by caregivers of AIDS orphans: lack of knowledge regarding the formal adoption of orphans; lengthy process administered by an increasingly overstretched system; bad behaviour by orphans; stress resulting to poor physical and mental health, strained personal relationships and lowering of standards of care; poverty; "role strain" and "identity"; interpersonal and family conflicts; isolation and fear for the future; excessive workload of having to care for children; and stigma and discrimination relating to HIV/AIDS. However, this study highlighted the following difficulties: poverty; stress and depression; family fights; adoption; bad influence on orphans by neighbours; education; lack of training; lack of social services support; lack of community support structures; and lack of prior planning by orphans' parents. The conclusions drawn from this study are that there were similar problems revealed in this study to those identified in the literature. For example, both literature and this study revealed poverty, stress and interpersonal and family conflicts as major problems experienced by caregivers. Grandparents and other family members who were caregivers in this study did not see "role strain" and "identity" as major stumbling blocks. Stigma and isolation were also some of the problems not directly experienced by most caregivers. However, it was evident that lack of involvement of some of these caregivers with the community, has led to their not experiencing stigmatisation and isolation. The following recommendations were made: caregivers should be given adequate training on how to use the grants given to orphans; researchers should use their research findings to influence government policy regarding termination of grants for orphans, that is, as long as orphans are still attending school or university, grants should not be terminated; universities and government should set aside special bursaries or study loans for orphans at universities, and these loans must only be paid when the orphans are in the position to do so; government should make extra funds available to give to caregivers as incentives; Social Welfare Department should be strengthen so that free counselling could be given to caregivers whenever is necessary; School-Based Support Teams (SBST) committees in schools should be capacitated and empowered; capacitate and empower non -governmental organisations (NGOs); and there should be a strong interaction between schools, NGOs, social workers, nurses and police. Limitations of the current study were also identified. This study could not show with absolute certainty whether the problems identified are related to orphanhood in general, rather than orphanhood by HIV/AIDS. Thus it was deemed necessary in future to have a comparison group of caregivers of orphans due to reasons other than HIV/AIDS. Other limitations included reliance on one population race. The study cannot ascertain whether these findings can be applicable to caregivers from other race groups such as white or coloured races. South Africa is a multicultural society with different norms and values. Thus, the way we react to certain stimuli might be influenced to a large extent by our customs and values. Further limitations included reliance on one specific type of caregiving. The study did not explore other type such as orphanages, but concentrated on what is regarded as the traditional safety net. / Thesis (M.Ed.)--North-West University, Vaal Triangle Campus, 2009.