Haynes alloy 282 is a new gamma prime (γ’) precipitation strengthened nickel-base superalloy developed for high temperature applications in land-based and aero turbine engines. Joining is a crucial process both during the manufacturing of new components and repair of service-damaged turbine parts. Unfortunately, the new superalloy cracks during laser beam welding (LBW), which is an attractive technique for joining superalloys components due to its low heat input characteristic that preclude the geometrical distortion of welded components. This research is therefore initiated with the goal of studying and developing an effective approach for preventing or minimizing cracking during LBW of the new superalloy Haynes 282. Careful and detailed electron microscopy and spectroscopy study reveal, for the first time, the formation of sub-micron grain boundary M5B3 particles, in the material. Microstructural study of welded specimens coupled with Gleeble thermo-mechanical physical simulations shows that the primary cause of weld heat affected zone (HAZ) cracking in the alloy is the sub-solidus liquation reaction of intergranular M5B3 borides in the material. Further weldability study showed that the HAZ liquation cracking problem worsens with reduction in welding heat input, which is normally necessary to produce the desired weld geometry with minimum distortion. In order to minimize the HAZ cracking during low heat input laser welding, microstructural modification of the alloy by heat treatment at 1080 - 1100oC has been developed. The pre-weld heat treatment minimizes cracking in the alloy by reducing the volume fraction of the newly identified M5B3 borides, while also minimizing non-equilibrium grain boundary segregation of boron liberated during dissociation of the boride particles. Further improvement in resistance to cracking was produced by subjecting the material to thermo-mechanically induced grain refinement coupled with a pre-weld heat treatment at 1080oC. This approach produces, for the first time, crack-free welds in this superalloy, and the benefit of this procedure in preventing weld cracking in the new material is preserved after post-weld heat treatment (PWHT), as additional cracking was not observed in welded specimens subjected to PWHT.

Evidence suggests that caring for orphans and vulnerable children affected by HIV and AIDS remains one of the greatest challenges facing South Africa. Statistics indicate that there are 1.91 million AIDS orphans in the country (UNICEF, 2012; Statistics South Africa, 2009:8)). The majority of these orphans live in rural and poor urban households. Caring for orphans and vulnerable children places severe strain on support systems, such as the extended family; this spills over into the community. Providing care and support also places an extra burden on the already overstretched welfare sector and drains state resources. The primarily objective of this study was to explore community resilience strategies on challenges faced by orphans and vulnerable children affected by HIV and AIDS in Ekurhuleni Metropolitan Municipality, Gauteng. A purposive sample of 32 participants was selected and field data were collected over a period of two months using a structured research guide. A combination of data collection methods was employed in order to explore different perspectives of community resilience strategies on challenges faced by orphans and vulnerable children affected by HIV and AIDS in Benoni. Emerging data illustrate a clear account on the impact of the AIDS epidemic in Benoni. All of the respondents were directly or indirectly affected by the epidemic. This should be located within the high prevalence of HIV and AIDS and the high number of orphans in Ekurhuleni. The study findings further suggest a correlation between socioeconomic challenges and the AIDS epidemic in Ekurhuleni. This is demonstrated through the challenges experienced by orphans and vulnerable children in Benoni, which include: non-disclosure by parents of their illness; economic deprivation and disrupted schooling; children caring for an ill parent with AIDS and child-headed households; emotional, sexual and economic exploitation, stigmatisation and discrimination. Despite these challenges, through community resilience the Benoni community has taken some initiatives to mitigate against these challenges. This includes the establishment of a community vi based organisation which provides basic services to orphans and vulnerable children in Benoni. To date this organisation has successfully provided material and psychosocial to more than 278 orphans. The success of this initiative confirms the importance of community driven interventions using the resilience framework to supports orphans and vulnerable, rather than dependency on the government imposed programmes- top down approach. However, community based programmes need to be strengthened by the government and non-governmental organisations in order to maximise benefits.

As South Africa is one of the countries with the highest HIVJAids prevalence in the world, many South Africans are affected by the pandemic. One of the structures being endangered by the HIVJAids pandemic is the education system. Educators are especially affected by the impact of the pandemic due to the fact that they not only have to cope with infected colleagues who are often absent, but are also burdened with numerous orphans and vulnerable children at their schools because of the pandemic. Sometimes these affected educators even have to care for their own loved ones who suffer from or die of the disease. The impact of the pandemic is personal stress, such as depression and suicidal ideation, plus professional impairment such as through increased workload and staff negativity. Affected educators are vulnerable, struggle to cope and are desperately in need of support, due to the pressure they experience regarding the pandemic. Current literature reports little support for educators affected by HIVJAids with regard to the personal and professional impact of the pandemic. This study focuses on determining the efficacy of REds (Resilient Educators), a support programme compiled to empower educators who are affected by HIVJAids, the implementation of which was also piloted by this study. A qualitative research design which included experimental and action research which focused on the latter (action research) was used. A purposive convenience sample consisting of eight volunteers from local primary schools participated. The researcher made use of a mixed-methods design for the pre and post-tests which included both qualitative and quantitative measuring instruments. REds was implemented over a period of nine consecutive weeks in a group setting and was continuously evaluated by the participants who proposed changes in order to improve the programme. In spite of being realistic about the obstacles they will face with regard to the HIVIAids pandemic, participants reported to be relieved, empowered and motivated to fight the effects of the pandemic. The quantitative results show some improvement in participants' experience of secondary trauma resulting from the impact of the pandemic. The results suggest that REds was efficacious, but that educators need continued support. Some modification of REds is also suggested action research affected impact. / Thesis (M.Ed.)--North-West University, Vaal Triangle Campus, 2007.

This study focuses on the impact of HIV/Aids on secondary school educators who are affected by the HIV/Aids pandemic. The study seeks to understand how the pandemic has impacted on educators and identify support needs of educators affected by HIV/Aids. Many educators are negatively affected by HIV/Aids due to the fact that their family members, loved ones, friends, learners and colleagues may be ill, dying or affected by HIV and Aids. Educators are personally and professionally affected by HIV/Aids. Personally many educators are emotionally, socially, spiritually and physically affected. Professionally many are negatively impacted as educator absenteeism rises, morale is lowered and professional roles become more complex. There are very few avenues of support for educators who are affected by the HIV pandemic. To determine how high school educators are affected and what their subsequent support needs are, this study followed a phenomenological design. Fourteen high school educators were interviewed. All participants taught at township schools in the Free State and were affected by the HIV pandemic. The data were coded with regard to how these educators were affected by the pandemic and what support they wished for. According to this study's findings, educators in township secondary schools in the Free State are personally and professionally affected. Their experiences are mostly negative. They wish for support from the Department of Education, school management, their colleagues and the community. Examples of requested support include training and counselling programmes, supportive attitudes and additional educators so that they might be assisted to cope with the HIV/Aids pandemic challenges. / Thesis (M.Ed.)--North-West University, Vaal Triangle Campus, 2009.

The aims of this research were to investigate the condition of the psychological well being of learners affected or orphaned by HIV/AIDS; investigate the way in which these learners perform at schools, investigate the nature and extent of social support these learners get from their families, community and society; investigate the condition of the physical well being of these learners; and make recommendations for their psychosocial support in order to enhance and strengthen their psychological well being. Findings from the literature review revealed that when HIV infected parents fall ill and die as a result of AIDS, usually a child or adolescent's life also often falls apart. This is an indication that with HIV and AIDS effects, the hardships hit well before children and adolescents are orphaned. This is to say, first a parent or breadwinner becomes ill with HIV or AIDS, and is unable to work. Then the entire family feels the economic impact - for example, children especially girls, must often drop out of school to go to work so that they can provide food for the family, care for their ill parents and look after their siblings. Such a phenomenon leads to the following psycho social problems in the lives of these children and adolescents: experience of grief and bereavement among children and adolescents affected by HIV/AIDS; introduction of major social change which may involve moving from a middle or upper -class urban home to a poor rural relative's home. It may involve separation from siblings, which is often done arbitrarily when orphaned children are divided among relatives without due considerations of their needs; increase in new labour responsibilities and instances of labour and work responsibility being given to children as young as five. Responsibilities and work in the household also include domestic chores, subsistence agriculture and provision of care giving to very young, old and ill members of the household. Work outside of the home may involve a variety of formal and informal labour, including farm work and begging for food and supplies in both community and beyond; a phenomenon of irregular school attendance and absconding from school; suffering from malnutrition and may not have access to available health services; vulnerability to HIV infection. Their risk for infection arises from the early onset of sexual activity, commercial sex and sexual abuse, all of which may me precipitated by economic need, peer pressure, lack of supervision, exploitation and rape; likelihood that as the ratio of the dependent children increases as a result of the HIV/AIDS epidemic, so will the chances of children being lured into trafficking and sexual exploitation; and manifestations of negative emotional responses such as fear, anger, depression, anxiety, feelings of dependency and so on. Findings from the empirical research revealed that learners who formed the population sample of this research are unhappy and sad to see their family members, that is, their parents and breadwinners, being ill, and as a result their health is also psycho socially affected; they do not have and cannot afford school uniform and there are no people or relatives who can help them with money to buy school uniform; and their mental health is not in good condition and that they had been ill, suffering from stress in the last six months. Recommendations with psycho-educational implications were made in the last chapter. / Thesis (M.Ed.)--North-West University, Vaal Triangle Campus, 2006.

As South Africa is one of the countries with the highest HIVJAids prevalence in the world, many South Africans are affected by the pandemic. One of the structures being endangered by the HIVJAids pandemic is the education system. Educators are especially affected by the impact of the pandemic due to the fact that they not only have to cope with infected colleagues who are often absent, but are also burdened with numerous orphans and vulnerable children at their schools because of the pandemic. Sometimes these affected educators even have to care for their own loved ones who suffer from or die of the disease. The impact of the pandemic is personal stress, such as depression and suicidal ideation, plus professional impairment such as through increased workload and staff negativity. Affected educators are vulnerable, struggle to cope and are desperately in need of support, due to the pressure they experience regarding the pandemic. Current literature reports little support for educators affected by HIVJAids with regard to the personal and professional impact of the pandemic. This study focuses on determining the efficacy of REds (Resilient Educators), a support programme compiled to empower educators who are affected by HIVJAids, the implementation of which was also piloted by this study. A qualitative research design which included experimental and action research which focused on the latter (action research) was used. A purposive convenience sample consisting of eight volunteers from local primary schools participated. The researcher made use of a mixed-methods design for the pre and post-tests which included both qualitative and quantitative measuring instruments. REds was implemented over a period of nine consecutive weeks in a group setting and was continuously evaluated by the participants who proposed changes in order to improve the programme. In spite of being realistic about the obstacles they will face with regard to the HIVIAids pandemic, participants reported to be relieved, empowered and motivated to fight the effects of the pandemic. The quantitative results show some improvement in participants' experience of secondary trauma resulting from the impact of the pandemic. The results suggest that REds was efficacious, but that educators need continued support. Some modification of REds is also suggested action research affected impact. / Thesis (M.Ed.)--North-West University, Vaal Triangle Campus, 2007.

This study focuses on the impact of HIV/Aids on secondary school educators who are affected by the HIV/Aids pandemic. The study seeks to understand how the pandemic has impacted on educators and identify support needs of educators affected by HIV/Aids. Many educators are negatively affected by HIV/Aids due to the fact that their family members, loved ones, friends, learners and colleagues may be ill, dying or affected by HIV and Aids. Educators are personally and professionally affected by HIV/Aids. Personally many educators are emotionally, socially, spiritually and physically affected. Professionally many are negatively impacted as educator absenteeism rises, morale is lowered and professional roles become more complex. There are very few avenues of support for educators who are affected by the HIV pandemic. To determine how high school educators are affected and what their subsequent support needs are, this study followed a phenomenological design. Fourteen high school educators were interviewed. All participants taught at township schools in the Free State and were affected by the HIV pandemic. The data were coded with regard to how these educators were affected by the pandemic and what support they wished for. According to this study's findings, educators in township secondary schools in the Free State are personally and professionally affected. Their experiences are mostly negative. They wish for support from the Department of Education, school management, their colleagues and the community. Examples of requested support include training and counselling programmes, supportive attitudes and additional educators so that they might be assisted to cope with the HIV/Aids pandemic challenges. / Thesis (M.Ed.)--North-West University, Vaal Triangle Campus, 2009.

The aims of this research were to investigate the condition of the psychological well being of learners affected or orphaned by HIV/AIDS; investigate the way in which these learners perform at schools, investigate the nature and extent of social support these learners get from their families, community and society; investigate the condition of the physical well being of these learners; and make recommendations for their psychosocial support in order to enhance and strengthen their psychological well being. Findings from the literature review revealed that when HIV infected parents fall ill and die as a result of AIDS, usually a child or adolescent's life also often falls apart. This is an indication that with HIV and AIDS effects, the hardships hit well before children and adolescents are orphaned. This is to say, first a parent or breadwinner becomes ill with HIV or AIDS, and is unable to work. Then the entire family feels the economic impact - for example, children especially girls, must often drop out of school to go to work so that they can provide food for the family, care for their ill parents and look after their siblings. Such a phenomenon leads to the following psycho social problems in the lives of these children and adolescents: experience of grief and bereavement among children and adolescents affected by HIV/AIDS; introduction of major social change which may involve moving from a middle or upper -class urban home to a poor rural relative's home. It may involve separation from siblings, which is often done arbitrarily when orphaned children are divided among relatives without due considerations of their needs; increase in new labour responsibilities and instances of labour and work responsibility being given to children as young as five. Responsibilities and work in the household also include domestic chores, subsistence agriculture and provision of care giving to very young, old and ill members of the household. Work outside of the home may involve a variety of formal and informal labour, including farm work and begging for food and supplies in both community and beyond; a phenomenon of irregular school attendance and absconding from school; suffering from malnutrition and may not have access to available health services; vulnerability to HIV infection. Their risk for infection arises from the early onset of sexual activity, commercial sex and sexual abuse, all of which may me precipitated by economic need, peer pressure, lack of supervision, exploitation and rape; likelihood that as the ratio of the dependent children increases as a result of the HIV/AIDS epidemic, so will the chances of children being lured into trafficking and sexual exploitation; and manifestations of negative emotional responses such as fear, anger, depression, anxiety, feelings of dependency and so on. Findings from the empirical research revealed that learners who formed the population sample of this research are unhappy and sad to see their family members, that is, their parents and breadwinners, being ill, and as a result their health is also psycho socially affected; they do not have and cannot afford school uniform and there are no people or relatives who can help them with money to buy school uniform; and their mental health is not in good condition and that they had been ill, suffering from stress in the last six months. Recommendations with psycho-educational implications were made in the last chapter. / Thesis (M.Ed.)--North-West University, Vaal Triangle Campus, 2006.

Haynes alloy 282 is a new gamma prime (γ’) precipitation strengthened nickel-base superalloy developed for high temperature applications in land-based and aero turbine engines. Joining is a crucial process both during the manufacturing of new components and repair of service-damaged turbine parts. Unfortunately, the new superalloy cracks during laser beam welding (LBW), which is an attractive technique for joining superalloys components due to its low heat input characteristic that preclude the geometrical distortion of welded components. This research is therefore initiated with the goal of studying and developing an effective approach for preventing or minimizing cracking during LBW of the new superalloy Haynes 282. Careful and detailed electron microscopy and spectroscopy study reveal, for the first time, the formation of sub-micron grain boundary M5B3 particles, in the material. Microstructural study of welded specimens coupled with Gleeble thermo-mechanical physical simulations shows that the primary cause of weld heat affected zone (HAZ) cracking in the alloy is the sub-solidus liquation reaction of intergranular M5B3 borides in the material. Further weldability study showed that the HAZ liquation cracking problem worsens with reduction in welding heat input, which is normally necessary to produce the desired weld geometry with minimum distortion. In order to minimize the HAZ cracking during low heat input laser welding, microstructural modification of the alloy by heat treatment at 1080 - 1100oC has been developed. The pre-weld heat treatment minimizes cracking in the alloy by reducing the volume fraction of the newly identified M5B3 borides, while also minimizing non-equilibrium grain boundary segregation of boron liberated during dissociation of the boride particles. Further improvement in resistance to cracking was produced by subjecting the material to thermo-mechanically induced grain refinement coupled with a pre-weld heat treatment at 1080oC. This approach produces, for the first time, crack-free welds in this superalloy, and the benefit of this procedure in preventing weld cracking in the new material is preserved after post-weld heat treatment (PWHT), as additional cracking was not observed in welded specimens subjected to PWHT.

Στην παρούσα εργασία αξιολογήθηκαν τα κατολισθητικά φαινόμενα που εντοπίστηκαν στους πυρόπληκτους Δήμους του Νομού Ηλείας. Δίνεται ιδιαίτερη έμφαση στα έργα αποκατάστασης στο Δήμο Πηνείας, όπου επλήγη από τις καταστροφικές πυρκαγιές τον Αύγουστο του 2007. Συνολικά καταγράφηκαν εννέα (9) θέσεις σε οικισμούς του Δήμου Πηνείας στις οποίες παρουσιάζονται προβλήματα κατολισθήσεων. Παρατηρήθηκαν αστοχίες επιχωμάτων οδών, εδαφικές ροές, αβαθείς περιστροφικές ολισθήσεις, εδαφικοί ερπυσμοί, καταπτώσεις αποσαθρωμένων βραχωδών τεμαχών και επιφανειακές διαβρώσεις λόγω της δράσης των επιφανειακών νερών και της απώλειας της βλάστησης μετά τις πυρκαγιές. Στις θέσεις αυτές, μελετήθηκαν και αξιολογήθηκαν όλα τα προτεινόμενα μέτρα προστασίας και αντιμετώπισης όπως αυτά προτάθηκαν σε παλαιότερη μελέτη που είχε εκπονηθεί από την Περιφέρεια Δυτικής Ελλάδας. Στη συνέχεια, η έρευνα επικεντρώθηκε στην κατολίσθηση του οικισμού Μαζαράκι, που εκδηλώθηκε μετά τις καταστροφικές πυρκαγιές του 2007 και εξελίχθηκε μετά από παρατεταμένες βροχοπτώσεις το χειμώνα 2009-2010. Πραγματοποιήθηκε λεπτομερής γεωτεχνική - τεχνικογεωλογική έρευνα για την αντιμετώπιση της μετακίνησης της κατολισθαίνουσας ζώνης. Έπειτα από την εκτέλεση δύο (2) δειγματοληπτικών γεωτρήσεων και εργαστηριακών δοκιμών προσδιορίστηκαν τέσσερις (4) γεωτεχνικές ενότητες: i) Ολισθημένα υλικά- αποσαθρωμένα υλικά (SC), ii) Aργιλώδης άμμος (SC), iii) Αργιλώδης άμμος με χάλικες και θραύσματα (SC), iv) Ψηφιδοπαγές (GW-GC). Στην αστοχία αυτή που μελετήθηκε, έγινε ανάλυση οριακής ευστάθειας πρανών χρησιμοποιώντας το λογισμικό SLIDE 5.0, Rock science Inc. Το πρόγραμμα έδειξε την ασταθή κατάσταση του πρανούς με συντελεστές ασφάλειας Fs<0,5 για διαφορετικές επιφάνειες ολίσθησης σε όλη την κατολισθαίνουσα μάζα. Για την βελτίωση του συντελεστή ασφάλειας Fs προτείναμε μέτρα εξυγίανσης και αποκατάστασης του πρανούς. Με την εφαρμογή των μέτρων αυτών παρατηρήθηκε ότι ο συντελεστής ασφάλειας αυξήθηκε ξεπερνώντας την τιμή Fs=3. / In this study, we evaluated the landslides events that indentified in wildfire affected areas in Ilia Prefecture (Peloponnesus, Greece). Specifically, there was an evaluation of the remedial measures in the Municipality of Pineia that were hit by the wildfires in August 2007. In the first part of this study, nine (9) landslide phenomena were detected in the villages of Pineia Municipality. Road embankment failure, earth flows, earth slides and falls, debris slides and falls, soil creep, earth slump and surface erosion were observed. All caused by the effect of surface water and loss of vegetation after the fires. We studied all the remedial and protection measures for these nine (9) landslide cases that were proposed in a previous study which was performed by the Region of Western Greece. Then, the study focused on the landslide in Mazaraki village, which occurred after the devastating fires of 2007 and developed after the prolonged rainfalls during the winter of 2009-2010. Firstly, a detailed geotechnical investigation was performed for the landslide zone treatment. After two (2) drill-core sampling processes and laboratory analysis, the studied materials were classified in four (4) geotechnical units: i) weathering materials (SC), ii) clayey sand (SC), iii) clayey sand with gravels and fragments (SC), iv) anglomerate (GW-GC). In this landslide zone, we used the SLIDE 5.0 software, Rock science Inc. in order to analyze the slope stability. The program showed an unstable state of the slope with safety factor values Fs<0.5 for different slide surfaces in the landslide zone. To increase the factor Fs, we proposed some remedial and protection measures of the slope. Using these measures in the SLIDE software, we observed that the safe factor increased with values greater than Fs=3.