The design of an aquaculture facility on the Keiskamma River at Hamburg, Province of the Eastern Cape
- Authors: Scholtz, Jeanne
- Date: 2014
- Subjects: Aquaculture -- South Africa -- Eastern Cape
- Language: English
- Type: Thesis , Masters , MArch
- Identifier: http://hdl.handle.net/10948/5280 , vital:20836
- Description: This dissertation addresses the nature and potential of an intrusive architectural typology in a sensitive river estuary environment through an understanding of the functional design principles of an Aquaculture plant. Furthermore the research engages with cultural, historical and sociological objectives to celebrate the historical landscape. Hamburg is caught between its value as a historic wilderness and it's need to establish and maintain an economy to alleviate poverty. The project is conceived as a provocation and speculation on how these two demands may be hybridized as an alternative to the typical conservationist practices applied. Proposing a type of hybrid ecology where industry and endemic wildlife can not only co-exist but also be mutually beneficial.
- Full Text:
- Date Issued: 2014
- Authors: Scholtz, Jeanne
- Date: 2014
- Subjects: Aquaculture -- South Africa -- Eastern Cape
- Language: English
- Type: Thesis , Masters , MArch
- Identifier: http://hdl.handle.net/10948/5280 , vital:20836
- Description: This dissertation addresses the nature and potential of an intrusive architectural typology in a sensitive river estuary environment through an understanding of the functional design principles of an Aquaculture plant. Furthermore the research engages with cultural, historical and sociological objectives to celebrate the historical landscape. Hamburg is caught between its value as a historic wilderness and it's need to establish and maintain an economy to alleviate poverty. The project is conceived as a provocation and speculation on how these two demands may be hybridized as an alternative to the typical conservationist practices applied. Proposing a type of hybrid ecology where industry and endemic wildlife can not only co-exist but also be mutually beneficial.
- Full Text:
- Date Issued: 2014
The novel as cultural and historical archive: an examination of Marlene van Niekerk's Agaat (2006)
- Authors: Carvalho, Alyssa May
- Date: 2009
- Subjects: Van Niekerk, Marlene , South Africa Fiction , Afrikaans fiction -- 21st century
- Language: English
- Type: Thesis , Masters , MA
- Identifier: vital:8454 , http://hdl.handle.net/10948/1224 , Van Niekerk, Marlene , South Africa Fiction , Afrikaans fiction -- 21st century
- Description: This research engages with a contemporary theoretical debate in the literary field, namely the ability of fictional texts to contribute to archival records. Contemporary research in archival discourse suggests that there are many intersections between fiction and the archive. Using Hamilton and others’ seminal text Refiguring the Archive (2002) and Pasco’s “Literature as Historical Archive” (2004) as point of departure, this dissertation offers an analysis of the South African English translation of Marlene van Niekerk’s Agaat (2004, translated 2006). In both form and function, the novel is viewed as a simulation of an archive. In Agaat, Van Niekerk has compiled a fictional archive of two indigenous South African cultures through her portrayal of the two main characters: Afrikaner culture during apartheid as embedded in the focalization of Milla de Wet and remnants of Khoi and/or San culture as emerge from the fictionalised subjectivity of her coloured housekeeper-nurse, Agaat. Through a conceptual and theoretical exploration of archival discourse, I argue that literary texts, such as Van Niekerk’s novel, have the potential to refigure (or creatively redefine) the archive and to enhance its scope and relevance, especially as South Africa undergoes transformation.
- Full Text:
- Date Issued: 2009
- Authors: Carvalho, Alyssa May
- Date: 2009
- Subjects: Van Niekerk, Marlene , South Africa Fiction , Afrikaans fiction -- 21st century
- Language: English
- Type: Thesis , Masters , MA
- Identifier: vital:8454 , http://hdl.handle.net/10948/1224 , Van Niekerk, Marlene , South Africa Fiction , Afrikaans fiction -- 21st century
- Description: This research engages with a contemporary theoretical debate in the literary field, namely the ability of fictional texts to contribute to archival records. Contemporary research in archival discourse suggests that there are many intersections between fiction and the archive. Using Hamilton and others’ seminal text Refiguring the Archive (2002) and Pasco’s “Literature as Historical Archive” (2004) as point of departure, this dissertation offers an analysis of the South African English translation of Marlene van Niekerk’s Agaat (2004, translated 2006). In both form and function, the novel is viewed as a simulation of an archive. In Agaat, Van Niekerk has compiled a fictional archive of two indigenous South African cultures through her portrayal of the two main characters: Afrikaner culture during apartheid as embedded in the focalization of Milla de Wet and remnants of Khoi and/or San culture as emerge from the fictionalised subjectivity of her coloured housekeeper-nurse, Agaat. Through a conceptual and theoretical exploration of archival discourse, I argue that literary texts, such as Van Niekerk’s novel, have the potential to refigure (or creatively redefine) the archive and to enhance its scope and relevance, especially as South Africa undergoes transformation.
- Full Text:
- Date Issued: 2009
East London and its geographical setting
- Authors: Moult, Frank Leslie
- Date: 1951
- Subjects: East London (South Africa) -- Geography
- Language: English
- Type: Thesis , Masters , MA
- Identifier: vital:4874 , http://hdl.handle.net/10962/d1012908
- Description: Along the South African coast between Cape Town and Durban, a distance of 822 miles, are the two major ports, Port Elizabeth and East London. These two ports, rivals in some ways, have histories that are closely linked. Their harbours have been built at two of the most favourable spots along a coastline poorly endowed with natural harbours. East London, the fourth harbour of the Union of South Africa, is the only river port of any consequence, and had to win the mechanical fight against nature and the fight against prejudice that contended that her position was too close to a troublesome frontier. After a hundred years of growth, East London is a mature town, with the residential and industrial areas clearly defined. Her expansion will be along the lines of planned zoning. (2) Her population in 1950 was 910,195 of which 43,195 were European and 39,698 Native. Besides being a port, East London is a prominent holiday resort and, of recent years, is developing as an industrial town. A striking feature is the clean aspect of the town. Those two "miracles" of South Africa, the discovery of diamonds and the discovery of gold, stimulated the growth of East London; especially the discovery of diamonds since Kimberley was about 450 miles from this, its nearest harbour. But the river mouth at East London had very little natural advantage over the other river mouths along the coast. There was at the Buffalo Mouth no outstanding, decisive merit. In many matters, such as the railway, the bridge, the water supply, there was doubt, uncertainty and bickering, with subsequent decisions to shelve the latter or make use of a temporary expedient, because there were many mediocre alternatives but none which was supremely suitable. In 1852, Bishop Gray wrote, "East London ... .has as few natural advantages as any place I have seen claiming to be a port. I could have walked across the river without getting wet above the knee." Intro., p. i-ii.
- Full Text:
- Date Issued: 1951
- Authors: Moult, Frank Leslie
- Date: 1951
- Subjects: East London (South Africa) -- Geography
- Language: English
- Type: Thesis , Masters , MA
- Identifier: vital:4874 , http://hdl.handle.net/10962/d1012908
- Description: Along the South African coast between Cape Town and Durban, a distance of 822 miles, are the two major ports, Port Elizabeth and East London. These two ports, rivals in some ways, have histories that are closely linked. Their harbours have been built at two of the most favourable spots along a coastline poorly endowed with natural harbours. East London, the fourth harbour of the Union of South Africa, is the only river port of any consequence, and had to win the mechanical fight against nature and the fight against prejudice that contended that her position was too close to a troublesome frontier. After a hundred years of growth, East London is a mature town, with the residential and industrial areas clearly defined. Her expansion will be along the lines of planned zoning. (2) Her population in 1950 was 910,195 of which 43,195 were European and 39,698 Native. Besides being a port, East London is a prominent holiday resort and, of recent years, is developing as an industrial town. A striking feature is the clean aspect of the town. Those two "miracles" of South Africa, the discovery of diamonds and the discovery of gold, stimulated the growth of East London; especially the discovery of diamonds since Kimberley was about 450 miles from this, its nearest harbour. But the river mouth at East London had very little natural advantage over the other river mouths along the coast. There was at the Buffalo Mouth no outstanding, decisive merit. In many matters, such as the railway, the bridge, the water supply, there was doubt, uncertainty and bickering, with subsequent decisions to shelve the latter or make use of a temporary expedient, because there were many mediocre alternatives but none which was supremely suitable. In 1852, Bishop Gray wrote, "East London ... .has as few natural advantages as any place I have seen claiming to be a port. I could have walked across the river without getting wet above the knee." Intro., p. i-ii.
- Full Text:
- Date Issued: 1951
Perceptions on future fulfilment of visually impaired adolescent learners at the Khanyisa Special School
- Authors: Ciyana, Nontobeko Minica
- Date: 2008
- Subjects: Blind children -- Education -- South Africa -- Port Elizabeth , Children with visual disabilities -- Education -- South Africa -- Port Elizabeth , Special education -- South Africa -- Port Elizabeth
- Language: English
- Type: Thesis , Masters , MEd
- Identifier: vital:9538 , http://hdl.handle.net/10948/683 , Blind children -- Education -- South Africa -- Port Elizabeth , Children with visual disabilities -- Education -- South Africa -- Port Elizabeth , Special education -- South Africa -- Port Elizabeth
- Description: This research focuses on the perceptions of future fulfilment of visually impaired adolescent learners at the Khanyisa Special School. The qualitative research was undertaken at the selected special school, which is situated in Nelson Mandela Bay in the western region of the Eastern Cape Province of South Africa, with ten learners, ten parents and five teachers as participants. The concluding chapter suggests ways and recommendations to assist the visually impaired adolescent learners at the Khanyisa Special School financially and academically.
- Full Text:
- Date Issued: 2008
- Authors: Ciyana, Nontobeko Minica
- Date: 2008
- Subjects: Blind children -- Education -- South Africa -- Port Elizabeth , Children with visual disabilities -- Education -- South Africa -- Port Elizabeth , Special education -- South Africa -- Port Elizabeth
- Language: English
- Type: Thesis , Masters , MEd
- Identifier: vital:9538 , http://hdl.handle.net/10948/683 , Blind children -- Education -- South Africa -- Port Elizabeth , Children with visual disabilities -- Education -- South Africa -- Port Elizabeth , Special education -- South Africa -- Port Elizabeth
- Description: This research focuses on the perceptions of future fulfilment of visually impaired adolescent learners at the Khanyisa Special School. The qualitative research was undertaken at the selected special school, which is situated in Nelson Mandela Bay in the western region of the Eastern Cape Province of South Africa, with ten learners, ten parents and five teachers as participants. The concluding chapter suggests ways and recommendations to assist the visually impaired adolescent learners at the Khanyisa Special School financially and academically.
- Full Text:
- Date Issued: 2008
A study of the art object as performative
- Authors: Minkley, Emma Smith
- Date: 2016
- Subjects: Arts -- Miscellanea Art objects
- Language: English
- Type: Thesis , Masters , MTech
- Identifier: http://hdl.handle.net/10948/12042 , vital:27022
- Description: My research project explores conventions in art-making and viewing via the notion of the performative art object. The performative (derived from J.L. Austin and Judith Butler’s formulations of the word) is here used predominantly as a term to denote a generative, experiential and iterative process (in this case outlined by art theorist Barbara Bolt) in which intuitive or playful actions of both artist and spectator dictate the route of research. The project, following an A/r/tographical cycle of theoriapraxis-poesis (or theory/research - doing/learning - art/making) as defined by Rita Irwin, thus investigates the relations inherent between artists, spectators or viewers, and objects, and how these may change according to the spaces they are conceived in; from art gallery to urban “non-art” environments. It deals with the inclusion of process or performativity within, or in relation to the art object and how this take on the traditionally static object may have the capacity to change how artworks are envisaged, and more significantly, how they are received, in terms of the effects they (in combination with the viewer) have on the world around them. Blurred in the context of performativity, the art object may become a means of documenting process and in a sense may act as a ‘prop’ for artistic research. This enquiry has involved the study of process and play, as related to creative practice, via a series of object-based events or interventions (including gallery exhibitions and other “non-art” events initiated by the artist outside of conventional art-related space) which have been documented and included in the theoretical research as a means of providing a first-hand narrative of theoretical ideas put into practice. Here Diana Taylor’s understanding of interrelated modes of storing and enacting knowledge as posed in the notion of the archive and repertoire has been utilised as a means of collecting and collating performative and ephemeral research. These events/interventions have further served as a means of gauging viewer interaction and participation, thus actively involving the viewer in the creative act. Jacques Rancière’s notion of the emancipated spectator is here utilised to activate the role of the viewer. In this regard, Martin Heidegger’s concept of handiness or handling serves as a means of “emancipating” spectators by encouraging tactile viewership. It is my intent to open up or reveal new modes of thinking or doing within the viewer when he or she enters a state of performative play within these events. Here the status of the art object is challenged and in this way has the potential to subvert or confront problematic repetitions, both in the identity of the viewer and the space occupied in each event.
- Full Text:
- Date Issued: 2016
- Authors: Minkley, Emma Smith
- Date: 2016
- Subjects: Arts -- Miscellanea Art objects
- Language: English
- Type: Thesis , Masters , MTech
- Identifier: http://hdl.handle.net/10948/12042 , vital:27022
- Description: My research project explores conventions in art-making and viewing via the notion of the performative art object. The performative (derived from J.L. Austin and Judith Butler’s formulations of the word) is here used predominantly as a term to denote a generative, experiential and iterative process (in this case outlined by art theorist Barbara Bolt) in which intuitive or playful actions of both artist and spectator dictate the route of research. The project, following an A/r/tographical cycle of theoriapraxis-poesis (or theory/research - doing/learning - art/making) as defined by Rita Irwin, thus investigates the relations inherent between artists, spectators or viewers, and objects, and how these may change according to the spaces they are conceived in; from art gallery to urban “non-art” environments. It deals with the inclusion of process or performativity within, or in relation to the art object and how this take on the traditionally static object may have the capacity to change how artworks are envisaged, and more significantly, how they are received, in terms of the effects they (in combination with the viewer) have on the world around them. Blurred in the context of performativity, the art object may become a means of documenting process and in a sense may act as a ‘prop’ for artistic research. This enquiry has involved the study of process and play, as related to creative practice, via a series of object-based events or interventions (including gallery exhibitions and other “non-art” events initiated by the artist outside of conventional art-related space) which have been documented and included in the theoretical research as a means of providing a first-hand narrative of theoretical ideas put into practice. Here Diana Taylor’s understanding of interrelated modes of storing and enacting knowledge as posed in the notion of the archive and repertoire has been utilised as a means of collecting and collating performative and ephemeral research. These events/interventions have further served as a means of gauging viewer interaction and participation, thus actively involving the viewer in the creative act. Jacques Rancière’s notion of the emancipated spectator is here utilised to activate the role of the viewer. In this regard, Martin Heidegger’s concept of handiness or handling serves as a means of “emancipating” spectators by encouraging tactile viewership. It is my intent to open up or reveal new modes of thinking or doing within the viewer when he or she enters a state of performative play within these events. Here the status of the art object is challenged and in this way has the potential to subvert or confront problematic repetitions, both in the identity of the viewer and the space occupied in each event.
- Full Text:
- Date Issued: 2016
Depressive disorders and chronic comorbid disease states: a pharmacoepidemiological evaluation
- Authors: Kritiotis, Lia Costas
- Date: 2007
- Subjects: Depression, Mental , Child psychopathology , Adolescent psychopathology
- Language: English
- Type: Thesis , Masters , MSc
- Identifier: vital:10151 , http://hdl.handle.net/10948/653 , Depression, Mental , Child psychopathology , Adolescent psychopathology
- Description: The treatment of Depressive Disorders in patients with chronic comorbid disease states warrants careful consideration of the risk-benefit ratio pertaining to the pharmacokinetic and pharmacodynamic characteristics of the antidepressant being considered, against the physiological susceptibilities of the patient; potential drug-drug interactions and depressive symptoms. The primary aim of this study was to investigate the relationship between Depressive Disorders and the most frequently diagnosed chronic comorbid disease states in a depressed South African study population; and to comment on the appropriateness of antidepressants prescribed to these patients. This retrospective drug utilisation study consisted of two parts: the first part focused on the prevalence of the most frequently diagnosed chronic comorbidities in a depressed South African population (N = 21 171). The three most prevalent chronic comorbid disease states were Hypertension (52.87 percent), Lipid Disorders (20.40 percent) and Arthritis (16.70 percent). The second part of the study included an assessment of the antidepressants prescribed to depressed patients in 2004 (N = 6 150). Emphasis was placed on the suitability of antidepressants selected for depressed adult patients (18 years of age and older) with comorbid Hypertension, Lipid Disorders or Arthritis. SSRIs were prescribed most frequently to the depressed patients during 2004 (59.67 percent). SSRIs are the suggested first-line treatments for depressed patients with multiple chronic comorbid disease states. However, of the SSRIs, fluoxetine has the least favourable pharmacokinetic profile and was found to be the antidepressant prescribed most often. Amitriptyline, which was the TCA prescribed most frequently, produces the greatest degree of anticholinergic, sedative and hypotensive effects, relative to other agents in the same antidepressant class. Thus, it is not recommended as a first-line antidepressant, especially in depressed patients with comorbidities. This study identifies potential areas of intervention regarding antidepressant prescribing in depressed individuals with chronic comorbid disease states and offers recommendations to promote the selection of optimal, individualised drug treatment strategies for these patients.
- Full Text:
- Date Issued: 2007
- Authors: Kritiotis, Lia Costas
- Date: 2007
- Subjects: Depression, Mental , Child psychopathology , Adolescent psychopathology
- Language: English
- Type: Thesis , Masters , MSc
- Identifier: vital:10151 , http://hdl.handle.net/10948/653 , Depression, Mental , Child psychopathology , Adolescent psychopathology
- Description: The treatment of Depressive Disorders in patients with chronic comorbid disease states warrants careful consideration of the risk-benefit ratio pertaining to the pharmacokinetic and pharmacodynamic characteristics of the antidepressant being considered, against the physiological susceptibilities of the patient; potential drug-drug interactions and depressive symptoms. The primary aim of this study was to investigate the relationship between Depressive Disorders and the most frequently diagnosed chronic comorbid disease states in a depressed South African study population; and to comment on the appropriateness of antidepressants prescribed to these patients. This retrospective drug utilisation study consisted of two parts: the first part focused on the prevalence of the most frequently diagnosed chronic comorbidities in a depressed South African population (N = 21 171). The three most prevalent chronic comorbid disease states were Hypertension (52.87 percent), Lipid Disorders (20.40 percent) and Arthritis (16.70 percent). The second part of the study included an assessment of the antidepressants prescribed to depressed patients in 2004 (N = 6 150). Emphasis was placed on the suitability of antidepressants selected for depressed adult patients (18 years of age and older) with comorbid Hypertension, Lipid Disorders or Arthritis. SSRIs were prescribed most frequently to the depressed patients during 2004 (59.67 percent). SSRIs are the suggested first-line treatments for depressed patients with multiple chronic comorbid disease states. However, of the SSRIs, fluoxetine has the least favourable pharmacokinetic profile and was found to be the antidepressant prescribed most often. Amitriptyline, which was the TCA prescribed most frequently, produces the greatest degree of anticholinergic, sedative and hypotensive effects, relative to other agents in the same antidepressant class. Thus, it is not recommended as a first-line antidepressant, especially in depressed patients with comorbidities. This study identifies potential areas of intervention regarding antidepressant prescribing in depressed individuals with chronic comorbid disease states and offers recommendations to promote the selection of optimal, individualised drug treatment strategies for these patients.
- Full Text:
- Date Issued: 2007
A critical analysis of school computer studies syllabuses in South Africa with reference to university computer science curricula
- Authors: Roets, Rina Annette
- Date: 1992
- Subjects: Electronic data processing -- Study and teaching (Secondary) -- South Africa Electronic data processing -- Study and teaching (Higher) -- South Africa Electronic data processing -- Curricula -- South Africa
- Language: English
- Type: Thesis , Masters , MEd
- Identifier: vital:1471 , http://hdl.handle.net/10962/d1003352
- Description: This thesis analyses the existing and proposed Computer Studies syllabuses in South African schools. Thereafter it compares the South African syllabuses with syllabuses in the United Kingdom. An attempt is made to assess the objectives of the design of the new S.A. syllabus. University Computer Science syllabuses are examined in order to gauge the purported overlap between what is taught at schools and universities. Opinions are obtained on the problems which apparently exist in offering or teaching the subject at schools and universities by conducting surveys on syllabus designers and university Computer Science departments. Finally recommendations are made for future Computer Studies syllabuses.
- Full Text:
- Date Issued: 1992
- Authors: Roets, Rina Annette
- Date: 1992
- Subjects: Electronic data processing -- Study and teaching (Secondary) -- South Africa Electronic data processing -- Study and teaching (Higher) -- South Africa Electronic data processing -- Curricula -- South Africa
- Language: English
- Type: Thesis , Masters , MEd
- Identifier: vital:1471 , http://hdl.handle.net/10962/d1003352
- Description: This thesis analyses the existing and proposed Computer Studies syllabuses in South African schools. Thereafter it compares the South African syllabuses with syllabuses in the United Kingdom. An attempt is made to assess the objectives of the design of the new S.A. syllabus. University Computer Science syllabuses are examined in order to gauge the purported overlap between what is taught at schools and universities. Opinions are obtained on the problems which apparently exist in offering or teaching the subject at schools and universities by conducting surveys on syllabus designers and university Computer Science departments. Finally recommendations are made for future Computer Studies syllabuses.
- Full Text:
- Date Issued: 1992
Photodynamic antimicrobial chemotherapy activities of porphyrin- and phthalocyanine-platinum nanoparticle conjugates
- Authors: Managa, Muthumuni Elizabeth
- Date: 2015
- Subjects: Photochemotherapy , Anti-infective agents , Porphyrins , Phthalocyanines , Platinum , Nanoparticles , Bioconjugates , Electrospinning
- Language: English
- Type: Thesis , Masters , MSc
- Identifier: vital:4539 , http://hdl.handle.net/10962/d1017919
- Description: This work reports on the conjugation of differently shaped Pt nanoparticles (PtNPs) with ClGa(III) 5,10,15,20-tetrakis-(4-carboxyphenyl) porphyrin (1) as well as chloro - (5,10,15,20-tetrakis (4- (4- carboxy phenycarbonoimidoyl) phenyl) porphyrinato) gallium(III) (2) The work also reports on platination of dihydroxosilicon octacarboxyphthalocyanine (OH)₂SiOCPc (3) to give dihydroxosilicontris(diaquaplatinum)octacarboxyphthalocyanine (OH)₂SiOCPc(Pt)₃ (4). The resulting conjugates were used for photodynamic antimicrobial chemotherapy against S. aureus, E. coli and C. albicans. The degree of photo-inactivation is dependent on concentration of the conjugates, light dose (fluence) and illumination time. The log reduction obtained for 1 when conjugated to cubic PtNPs was 4.64 log (which indicate 99.99 percent of the bacteria have been killed), which is much higher than 3.94 log unit for 1-hexagonal PtNPs and 3.31 log units for 1-unshaped PtNPs. Complex 2 conjugated to hexagonal PtNPs showed 18 nm red shift in the Soret band when compared to 2 alone. Complex 2 and 2-hexagonal PtNPs as well showed promising photodynamic antimicrobial chemotherapy (PACT) activity against S. aureus, E. coli and C. albicans in solution where the log reduction obtained was 4.92, 3.76, and 3.95 respectively for 2-hexagonal PtNPs. The singlet oxygen quantum yields obtained were higher at 0.56 for 2-hexagonl PtNPs in DMF while that of 2 was 0.52 in the same solvent. This resulted in improved PACT activity for 2-hexagonal PtNPs compared to 2. Complex 4 showed slight blue shifting of the absorption spectrum when compared to complex 3 The antimicrobial activity of 4 were promising as the highest log reduction value was observed when compared to the porphyrin conjugates.
- Full Text:
- Date Issued: 2015
- Authors: Managa, Muthumuni Elizabeth
- Date: 2015
- Subjects: Photochemotherapy , Anti-infective agents , Porphyrins , Phthalocyanines , Platinum , Nanoparticles , Bioconjugates , Electrospinning
- Language: English
- Type: Thesis , Masters , MSc
- Identifier: vital:4539 , http://hdl.handle.net/10962/d1017919
- Description: This work reports on the conjugation of differently shaped Pt nanoparticles (PtNPs) with ClGa(III) 5,10,15,20-tetrakis-(4-carboxyphenyl) porphyrin (1) as well as chloro - (5,10,15,20-tetrakis (4- (4- carboxy phenycarbonoimidoyl) phenyl) porphyrinato) gallium(III) (2) The work also reports on platination of dihydroxosilicon octacarboxyphthalocyanine (OH)₂SiOCPc (3) to give dihydroxosilicontris(diaquaplatinum)octacarboxyphthalocyanine (OH)₂SiOCPc(Pt)₃ (4). The resulting conjugates were used for photodynamic antimicrobial chemotherapy against S. aureus, E. coli and C. albicans. The degree of photo-inactivation is dependent on concentration of the conjugates, light dose (fluence) and illumination time. The log reduction obtained for 1 when conjugated to cubic PtNPs was 4.64 log (which indicate 99.99 percent of the bacteria have been killed), which is much higher than 3.94 log unit for 1-hexagonal PtNPs and 3.31 log units for 1-unshaped PtNPs. Complex 2 conjugated to hexagonal PtNPs showed 18 nm red shift in the Soret band when compared to 2 alone. Complex 2 and 2-hexagonal PtNPs as well showed promising photodynamic antimicrobial chemotherapy (PACT) activity against S. aureus, E. coli and C. albicans in solution where the log reduction obtained was 4.92, 3.76, and 3.95 respectively for 2-hexagonal PtNPs. The singlet oxygen quantum yields obtained were higher at 0.56 for 2-hexagonl PtNPs in DMF while that of 2 was 0.52 in the same solvent. This resulted in improved PACT activity for 2-hexagonal PtNPs compared to 2. Complex 4 showed slight blue shifting of the absorption spectrum when compared to complex 3 The antimicrobial activity of 4 were promising as the highest log reduction value was observed when compared to the porphyrin conjugates.
- Full Text:
- Date Issued: 2015
The coping orientation and self-esteem of black learners enrolled in under-resourced schools in the Nelson Mandela Metropole
- Authors: Ogle, Zimbini
- Date: 2012
- Subjects: Educational psychology -- South Africa -- Port Elizabeth , Educational psychology -- Study and teaching -- South Africa -- Port Elizabeth , Self-esteem -- South Africa -- Port Elizabeth -- Problems, exercises, etc. , Right to education -- South Africa -- Port Elizabeth , Public schools -- South Africa -- Port Elizabeth
- Language: English
- Type: Thesis , Masters , MA
- Identifier: vital:9941 , http://hdl.handle.net/10948/d1012591 , Educational psychology -- South Africa -- Port Elizabeth , Educational psychology -- Study and teaching -- South Africa -- Port Elizabeth , Self-esteem -- South Africa -- Port Elizabeth -- Problems, exercises, etc. , Right to education -- South Africa -- Port Elizabeth , Public schools -- South Africa -- Port Elizabeth
- Description: It is common knowledge that the delivery of a high quality, well-resourced educational service to learners enrolled in state schools in the Eastern Cape has ground to a halt and this lack of service delivery has now become a pervasive problem. South African education has to a large extent failed to meet the needs of Black learners. Schools, like other contexts of childhood and adolescence are intimate places where youths construct identities, build a sense of self, read how society views them, develop the capacity to sustain relations and forge the skills to initiate change. These are the contexts where youth grow or shrink. Buildings in disrepair are not, therefore, merely a distraction; they are identity producing and selfdefining. There has been much debate on the topic of self-esteem and its relationship to school performance and academic achievement. Previous studies have highlighted that selfesteem and resilience do play a role in academic achievement. Despite the many challenges facing learners in under-resourced schools, many learners have overcome such challenges and achieved academic success. This study aimed to explore and describe the coping orientation and self-esteem of Black learners enrolled in under-resourced state schools in the Nelson Mandela Metropole. An exploratory, descriptive survey design was employed and eighty-five research participants completed the Orientation to Life Questionnaire 29 Item (OLQ 29 Item), Battle‟s Culture Free Self-Esteem Inventory Form AD (CFSEI Form AD) and a biographical questionnaire. Key findings revealed fairly high mean scores on the OLQ 29 Item and low total self-esteem scores. The General, Social and Personal self-esteem of the learners were found to be average. The results also revealed that learners with a high sense of coherence are likely to have high self-esteem; hence high sense of coherence is better explained by high self-esteem and low sense of coherence is better explained by low selfesteem.
- Full Text:
- Date Issued: 2012
- Authors: Ogle, Zimbini
- Date: 2012
- Subjects: Educational psychology -- South Africa -- Port Elizabeth , Educational psychology -- Study and teaching -- South Africa -- Port Elizabeth , Self-esteem -- South Africa -- Port Elizabeth -- Problems, exercises, etc. , Right to education -- South Africa -- Port Elizabeth , Public schools -- South Africa -- Port Elizabeth
- Language: English
- Type: Thesis , Masters , MA
- Identifier: vital:9941 , http://hdl.handle.net/10948/d1012591 , Educational psychology -- South Africa -- Port Elizabeth , Educational psychology -- Study and teaching -- South Africa -- Port Elizabeth , Self-esteem -- South Africa -- Port Elizabeth -- Problems, exercises, etc. , Right to education -- South Africa -- Port Elizabeth , Public schools -- South Africa -- Port Elizabeth
- Description: It is common knowledge that the delivery of a high quality, well-resourced educational service to learners enrolled in state schools in the Eastern Cape has ground to a halt and this lack of service delivery has now become a pervasive problem. South African education has to a large extent failed to meet the needs of Black learners. Schools, like other contexts of childhood and adolescence are intimate places where youths construct identities, build a sense of self, read how society views them, develop the capacity to sustain relations and forge the skills to initiate change. These are the contexts where youth grow or shrink. Buildings in disrepair are not, therefore, merely a distraction; they are identity producing and selfdefining. There has been much debate on the topic of self-esteem and its relationship to school performance and academic achievement. Previous studies have highlighted that selfesteem and resilience do play a role in academic achievement. Despite the many challenges facing learners in under-resourced schools, many learners have overcome such challenges and achieved academic success. This study aimed to explore and describe the coping orientation and self-esteem of Black learners enrolled in under-resourced state schools in the Nelson Mandela Metropole. An exploratory, descriptive survey design was employed and eighty-five research participants completed the Orientation to Life Questionnaire 29 Item (OLQ 29 Item), Battle‟s Culture Free Self-Esteem Inventory Form AD (CFSEI Form AD) and a biographical questionnaire. Key findings revealed fairly high mean scores on the OLQ 29 Item and low total self-esteem scores. The General, Social and Personal self-esteem of the learners were found to be average. The results also revealed that learners with a high sense of coherence are likely to have high self-esteem; hence high sense of coherence is better explained by high self-esteem and low sense of coherence is better explained by low selfesteem.
- Full Text:
- Date Issued: 2012
Strategies, challenges and socio-economic contribution of immigrant entrepreneurship in the Buffalo City Metropolitan Municipal Area
- Authors: Muridzo, Phillemon Dudzai
- Date: 2017
- Subjects: Minority business enterprises -- South Africa Entrepreneurship -- South Africa
- Language: English
- Type: Thesis , Masters , MSoc
- Identifier: http://hdl.handle.net/10353/17849 , vital:41375
- Description: Immigrants, in whatever country they settle, have always been involved in entrepreneurial activities mainly for survival, remittance and other purposes. Globally, immigrant entrepreneurship has significantly contributed to the economy of host nations. The aim of this research study is to investigate the business strategies, challenges and socio-economic contribution of immigrant entrepreneurship in the Buffalo City Metropolitan Municipal (BCMM) area, Eastern Cape, South Africa. This study builds upon fieldwork undertaken within the Buffalo City Metropolitan Municipal area situated in the Eastern Cape Province of South Africa. A Case Study research design was utilised, and it encompassed three kinds of data collection methods – indepth interviews, focus groups and direct observation. The key finding of this study indicated that as a consequence of the challenges they encounter, immigrant entrepreneurs in the Buffalo City Metropolitan Municipal area had devised different business strategies to ensure that their businesses remain afloat and profitable. Another key finding of the study is that immigrant entrepreneurs in the BCMM Area make significant socio-economic contributions to their host communities. In addition to other positive contributions, immigrant entrepreneurs add to the revitalization of neighbourhoods and provide employment to their respective communities.
- Full Text:
- Date Issued: 2017
- Authors: Muridzo, Phillemon Dudzai
- Date: 2017
- Subjects: Minority business enterprises -- South Africa Entrepreneurship -- South Africa
- Language: English
- Type: Thesis , Masters , MSoc
- Identifier: http://hdl.handle.net/10353/17849 , vital:41375
- Description: Immigrants, in whatever country they settle, have always been involved in entrepreneurial activities mainly for survival, remittance and other purposes. Globally, immigrant entrepreneurship has significantly contributed to the economy of host nations. The aim of this research study is to investigate the business strategies, challenges and socio-economic contribution of immigrant entrepreneurship in the Buffalo City Metropolitan Municipal (BCMM) area, Eastern Cape, South Africa. This study builds upon fieldwork undertaken within the Buffalo City Metropolitan Municipal area situated in the Eastern Cape Province of South Africa. A Case Study research design was utilised, and it encompassed three kinds of data collection methods – indepth interviews, focus groups and direct observation. The key finding of this study indicated that as a consequence of the challenges they encounter, immigrant entrepreneurs in the Buffalo City Metropolitan Municipal area had devised different business strategies to ensure that their businesses remain afloat and profitable. Another key finding of the study is that immigrant entrepreneurs in the BCMM Area make significant socio-economic contributions to their host communities. In addition to other positive contributions, immigrant entrepreneurs add to the revitalization of neighbourhoods and provide employment to their respective communities.
- Full Text:
- Date Issued: 2017
Effects of treatment on Lantana camara (L.) and the restoration potential of riparian seed banks in cleared areas of the Victoria Falls World Heritage Site, Livingstone, Zambia
- Nang'alelwa, Michael Mubitelela
- Authors: Nang'alelwa, Michael Mubitelela
- Date: 2010
- Subjects: Lantana camara -- Victoria Falls (Zambia and Zimbabwe) , Lantana camara -- Biological control -- Victoria Falls (Zambia and Zimbabwe) , Invasive plants -- Biological control -- Victoria Falls (Zambia and Zimbabwe) , Riparian restoration -- Victoria Falls (Zambia and Zimbabwe) , Riparian ecology -- Victoria Falls (Zambia and Zimbabwe)
- Language: English
- Type: Thesis , Masters , MSc
- Identifier: vital:4217 , http://hdl.handle.net/10962/d1003786 , Lantana camara -- Victoria Falls (Zambia and Zimbabwe) , Lantana camara -- Biological control -- Victoria Falls (Zambia and Zimbabwe) , Invasive plants -- Biological control -- Victoria Falls (Zambia and Zimbabwe) , Riparian restoration -- Victoria Falls (Zambia and Zimbabwe) , Riparian ecology -- Victoria Falls (Zambia and Zimbabwe)
- Description: The exotic plant Lantana camara L. has invaded the riparian areas of the Victoria Falls World Heritage Site in Livingstone, southern Zambia, threatening native plant communities which support populations of species of special concern. I trialled the mechanical control method of manual uprooting and 3 different herbicides applied through paint brushing of an imazapyr concentrate at 250g. l¯¹, spraying on cut stumps with metsulfron methyl at 600g.l¯¹, and foliar spraying on re-emergent lantana foliage with glyphosate at a dosage of 166g. l¯¹ in July 2008 in 20 100m2 treatment plots, 5 invaded control plots and 5 uninvaded controls. Follow-up treatments for re-sprouting lantana stumps and emerging seedlings were undertaken in June 2009. I measured effectiveness of the methods using adult lantana mortality in June 2009 and lantana seedling density in the different treatment plots during the follow-up exercise. The cost of the various methods and human labour applied were compared across the four treatments at initial clear and at follow-up. All treatments recorded a high adult lantana mortality rate, though there were no significant differences in lantana adult mortality amongst the treatments. Overall, uprooting had the highest adult mortality, followed by imazapyr, metsulfron and lastly glyphosate. Germination of lantana seedlings after clearing was high for all treatments but with no significant differences occurring between the treatments. Both adult lantana mortality and seedling density were however significantly different from the control. With labour included, chemical costs were far higher relative to uprooting, though uprooting costs were the highest when it came to the follow-up because of the emerging seedlings and some resprouting stumps. The effects of mechanical and chemical treatments on vegetation composition in the cleared areas were also assessed in order to detect any non-target and medium term effects of treatments. Contrary to expectation, none of the chemicals showed any significant effects on vegetation composition in the short and medium-term and no significant differences were found in plant species richness, diversity and seedling density between invaded and uninvaded plots at baseline, in October 2008 and in September 2009. In order to determine potential for unaided vegetation recovery in the riparian areas of the study site after lantana clearing, I conducted an investigation of soil seed banks and seed rain using 60 seed bank samples measuring 1800m³ collected from 30 invaded and uninvaded plots. Using the seedling emergence method, 1, 991 seedlings belonging to 66 species representing 27 families germinated from the seed bank. Sedges (Cyperaceae family) were the most abundant taxa in the seed banks from invaded areas, followed by Ageratum conyzoides, lantana, Triumfetta annua and Achyranthes aspera which also occurred in the uninvaded soil seed banks. The seed banks from uninvaded plots were dominated by the grass Oplismenus hirtellus. Overall, species richness, diversity and seedling density from seed banks in invaded areas did not differ significantly from seed bank in uninvaded areas and there was a low similarity in species composition when above ground vegetation was compared to seed banks from invaded and uninvaded areas. It would appear if natural regeneration occured from the current seed bank in disturbed areas, future vegetation would largely comprise of short lived, early successional species in the short term as the seed bank is dominated by non-native herbaceous weedy species. From the seed traps investigating seed rain, a total of 27 species numbering 623 individual seeds were found in the thirty 1m² seedtraps distributed in invaded and uninvaded areas at the five sites, over an intermittent period of three months. Lantana had the highest monthly arrival rate in the seed traps followed by Phoenix reclinata and Ricinus communis. The number of species with invasive potential found in the seed traps located in invaded areas was more than that found in seed traps under native vegetation cover by far. Considerable forest remnants still occur around the invaded sites, and these could serve as an important source for long-term natural re-establishment of native vegetation if seed availability by animals and wind dispersal continues, while the re-invasion of lantana is prevented by ongoing follow-ups and futher clearing of lantana invaded areas. It is concluded that while uprooting and other treatments are effective in the control of lantana, its successful control in the Victoria Falls World Heritage Site will require extensive clearing to keep it from reinvading infested areas after clearing as shown by the seed rain data. The high seedling density of lantana in the seed banks and in the cleared areas shows the need for ongoing follow-up in order to deplete soil stored seed banks. There is need for longer term research to establish what the exact follow-up requirements are in order to contain lantana re-infestation and create favourable micro-sites for native species to establish. It is predicted that ongoing lantana control in the cleared plots will most likely initiate long-term community recovery.
- Full Text:
- Date Issued: 2010
- Authors: Nang'alelwa, Michael Mubitelela
- Date: 2010
- Subjects: Lantana camara -- Victoria Falls (Zambia and Zimbabwe) , Lantana camara -- Biological control -- Victoria Falls (Zambia and Zimbabwe) , Invasive plants -- Biological control -- Victoria Falls (Zambia and Zimbabwe) , Riparian restoration -- Victoria Falls (Zambia and Zimbabwe) , Riparian ecology -- Victoria Falls (Zambia and Zimbabwe)
- Language: English
- Type: Thesis , Masters , MSc
- Identifier: vital:4217 , http://hdl.handle.net/10962/d1003786 , Lantana camara -- Victoria Falls (Zambia and Zimbabwe) , Lantana camara -- Biological control -- Victoria Falls (Zambia and Zimbabwe) , Invasive plants -- Biological control -- Victoria Falls (Zambia and Zimbabwe) , Riparian restoration -- Victoria Falls (Zambia and Zimbabwe) , Riparian ecology -- Victoria Falls (Zambia and Zimbabwe)
- Description: The exotic plant Lantana camara L. has invaded the riparian areas of the Victoria Falls World Heritage Site in Livingstone, southern Zambia, threatening native plant communities which support populations of species of special concern. I trialled the mechanical control method of manual uprooting and 3 different herbicides applied through paint brushing of an imazapyr concentrate at 250g. l¯¹, spraying on cut stumps with metsulfron methyl at 600g.l¯¹, and foliar spraying on re-emergent lantana foliage with glyphosate at a dosage of 166g. l¯¹ in July 2008 in 20 100m2 treatment plots, 5 invaded control plots and 5 uninvaded controls. Follow-up treatments for re-sprouting lantana stumps and emerging seedlings were undertaken in June 2009. I measured effectiveness of the methods using adult lantana mortality in June 2009 and lantana seedling density in the different treatment plots during the follow-up exercise. The cost of the various methods and human labour applied were compared across the four treatments at initial clear and at follow-up. All treatments recorded a high adult lantana mortality rate, though there were no significant differences in lantana adult mortality amongst the treatments. Overall, uprooting had the highest adult mortality, followed by imazapyr, metsulfron and lastly glyphosate. Germination of lantana seedlings after clearing was high for all treatments but with no significant differences occurring between the treatments. Both adult lantana mortality and seedling density were however significantly different from the control. With labour included, chemical costs were far higher relative to uprooting, though uprooting costs were the highest when it came to the follow-up because of the emerging seedlings and some resprouting stumps. The effects of mechanical and chemical treatments on vegetation composition in the cleared areas were also assessed in order to detect any non-target and medium term effects of treatments. Contrary to expectation, none of the chemicals showed any significant effects on vegetation composition in the short and medium-term and no significant differences were found in plant species richness, diversity and seedling density between invaded and uninvaded plots at baseline, in October 2008 and in September 2009. In order to determine potential for unaided vegetation recovery in the riparian areas of the study site after lantana clearing, I conducted an investigation of soil seed banks and seed rain using 60 seed bank samples measuring 1800m³ collected from 30 invaded and uninvaded plots. Using the seedling emergence method, 1, 991 seedlings belonging to 66 species representing 27 families germinated from the seed bank. Sedges (Cyperaceae family) were the most abundant taxa in the seed banks from invaded areas, followed by Ageratum conyzoides, lantana, Triumfetta annua and Achyranthes aspera which also occurred in the uninvaded soil seed banks. The seed banks from uninvaded plots were dominated by the grass Oplismenus hirtellus. Overall, species richness, diversity and seedling density from seed banks in invaded areas did not differ significantly from seed bank in uninvaded areas and there was a low similarity in species composition when above ground vegetation was compared to seed banks from invaded and uninvaded areas. It would appear if natural regeneration occured from the current seed bank in disturbed areas, future vegetation would largely comprise of short lived, early successional species in the short term as the seed bank is dominated by non-native herbaceous weedy species. From the seed traps investigating seed rain, a total of 27 species numbering 623 individual seeds were found in the thirty 1m² seedtraps distributed in invaded and uninvaded areas at the five sites, over an intermittent period of three months. Lantana had the highest monthly arrival rate in the seed traps followed by Phoenix reclinata and Ricinus communis. The number of species with invasive potential found in the seed traps located in invaded areas was more than that found in seed traps under native vegetation cover by far. Considerable forest remnants still occur around the invaded sites, and these could serve as an important source for long-term natural re-establishment of native vegetation if seed availability by animals and wind dispersal continues, while the re-invasion of lantana is prevented by ongoing follow-ups and futher clearing of lantana invaded areas. It is concluded that while uprooting and other treatments are effective in the control of lantana, its successful control in the Victoria Falls World Heritage Site will require extensive clearing to keep it from reinvading infested areas after clearing as shown by the seed rain data. The high seedling density of lantana in the seed banks and in the cleared areas shows the need for ongoing follow-up in order to deplete soil stored seed banks. There is need for longer term research to establish what the exact follow-up requirements are in order to contain lantana re-infestation and create favourable micro-sites for native species to establish. It is predicted that ongoing lantana control in the cleared plots will most likely initiate long-term community recovery.
- Full Text:
- Date Issued: 2010
Assessment of the flocculating efficiency of bioflocculant produced by bacillus sp. Aemreg4 isolated from Tyhume river, Eastern Cape, South Africa
- Authors: Ntsangani, Nozipho
- Date: 2016
- Subjects: Flocculants
- Language: English
- Type: Thesis , Masters , MSc (Biochemistry)
- Identifier: vital:11357 , http://hdl.handle.net/10353/d1021324
- Description: Bioflocculants are flocculating substances produced by microorganisms during growth and have recently received considerable attention from researchers; due to their biodegradability, non-toxicity and lack of secondary pollution from degradation intermediates. This study evaluated the efficiency of bioflocculant produced by Bacillus sp. AEMREG4 isolated from Tyhume River. The bacterial identification was through 16S rDNA sequencing; nucleotide sequences were deposited in GenBank as Bacillus sp. AEMREG4 with an Accession number KP406729. The optimum culture conditions for bioflocculant production were an inoculum size of 4% (v/v) and starch as well as yeast extract as sole carbon and nitrogen sources respectively. The addition of CaCl2 enhanced the flocculating activity, at a wide range of pH 4-10 and the highest flocculating activity was reached at an initial pH 8 (80%). A bioflocculant yield of 0.78 g was recovered from 1 L of culture broth. The optimum flocculating activity of 78% was reached at the lowest bioflocculant dosage of 0.1 mg/ml and the presence of divalent cations (Ca2+, Mn2+ and Mg2+) as well as a trivalent cation (Al3+) enhanced flocculating activity. The purified bioflocculant retained more than 70% flocculating activity when subjected to heating at 100 °C for 1 h and maximum flocculating activity of 83% was achieved at both acidic and basic pH values of 3 and 10 respectively. Chemical analysis showed that the bioflocculant is predominantly polysaccharide. The Fourier transform infrared (FTIR) spectrum revealed the presence of carboxyl, hydroxyl and methoxyl groups as the functional moieties and the scanning electron microscopy (SEM) imaging of the purified bioflocculant showed its morphological structure as rod-shaped which contributes to its high flocculating efficiency. The high flocculation activity displayed by this bioflocculant indicates its potential suitability for industrial application.Keywords: Bioflocculant, Bacillus sp. AEMREG4, flocculating activity.
- Full Text:
- Date Issued: 2016
- Authors: Ntsangani, Nozipho
- Date: 2016
- Subjects: Flocculants
- Language: English
- Type: Thesis , Masters , MSc (Biochemistry)
- Identifier: vital:11357 , http://hdl.handle.net/10353/d1021324
- Description: Bioflocculants are flocculating substances produced by microorganisms during growth and have recently received considerable attention from researchers; due to their biodegradability, non-toxicity and lack of secondary pollution from degradation intermediates. This study evaluated the efficiency of bioflocculant produced by Bacillus sp. AEMREG4 isolated from Tyhume River. The bacterial identification was through 16S rDNA sequencing; nucleotide sequences were deposited in GenBank as Bacillus sp. AEMREG4 with an Accession number KP406729. The optimum culture conditions for bioflocculant production were an inoculum size of 4% (v/v) and starch as well as yeast extract as sole carbon and nitrogen sources respectively. The addition of CaCl2 enhanced the flocculating activity, at a wide range of pH 4-10 and the highest flocculating activity was reached at an initial pH 8 (80%). A bioflocculant yield of 0.78 g was recovered from 1 L of culture broth. The optimum flocculating activity of 78% was reached at the lowest bioflocculant dosage of 0.1 mg/ml and the presence of divalent cations (Ca2+, Mn2+ and Mg2+) as well as a trivalent cation (Al3+) enhanced flocculating activity. The purified bioflocculant retained more than 70% flocculating activity when subjected to heating at 100 °C for 1 h and maximum flocculating activity of 83% was achieved at both acidic and basic pH values of 3 and 10 respectively. Chemical analysis showed that the bioflocculant is predominantly polysaccharide. The Fourier transform infrared (FTIR) spectrum revealed the presence of carboxyl, hydroxyl and methoxyl groups as the functional moieties and the scanning electron microscopy (SEM) imaging of the purified bioflocculant showed its morphological structure as rod-shaped which contributes to its high flocculating efficiency. The high flocculation activity displayed by this bioflocculant indicates its potential suitability for industrial application.Keywords: Bioflocculant, Bacillus sp. AEMREG4, flocculating activity.
- Full Text:
- Date Issued: 2016
Ernesto "Che" Guevara : a psychobiographical study
- Authors: Kolesky, Candice
- Date: 2010
- Subjects: Guevara, Che, 1928-1967 , Psychology -- Biographical methods
- Language: English
- Type: Thesis , Masters , MA
- Identifier: vital:9864 , http://hdl.handle.net/10948/1512 , Guevara, Che, 1928-1967 , Psychology -- Biographical methods
- Description: Psychobiography is a qualitative approach to exploring and understanding the life story of an individual through the lens of psychological theory. The application of theory is typically done on the finished lives of well-known or enigmatic people. This study explores and describes the psychological development across the lifespan of Ernesto “Che” Guevara, by applying the Individual Psychology of Alfred Adler. Che Guevara was an Argentine Marxist revolutionary, physician, author, guerrilla leader, and major figure of the Cuban Revolution. Since his death, his image has become a symbol for revolution within popular culture. Extensive data has been examined in this work to ensure an accurate description of Guevara’s life. Alexander’s model of identifying salient themes was used to analyze the data within a conceptual framework derived from the theory. Guevara was fiercely loyal to his cause, at the expense of the lives of many Cuban citizens as well as his own family, whom he spent little time with. He justified this with his firmly held belief that the end justified the means and that he was always fighting for the greater good. He quite literally dedicated his life to his cause, which is the reason that he has become a modern day symbol for revolution. It is however unfortunate that this came at such a great personal expense.
- Full Text:
- Date Issued: 2010
- Authors: Kolesky, Candice
- Date: 2010
- Subjects: Guevara, Che, 1928-1967 , Psychology -- Biographical methods
- Language: English
- Type: Thesis , Masters , MA
- Identifier: vital:9864 , http://hdl.handle.net/10948/1512 , Guevara, Che, 1928-1967 , Psychology -- Biographical methods
- Description: Psychobiography is a qualitative approach to exploring and understanding the life story of an individual through the lens of psychological theory. The application of theory is typically done on the finished lives of well-known or enigmatic people. This study explores and describes the psychological development across the lifespan of Ernesto “Che” Guevara, by applying the Individual Psychology of Alfred Adler. Che Guevara was an Argentine Marxist revolutionary, physician, author, guerrilla leader, and major figure of the Cuban Revolution. Since his death, his image has become a symbol for revolution within popular culture. Extensive data has been examined in this work to ensure an accurate description of Guevara’s life. Alexander’s model of identifying salient themes was used to analyze the data within a conceptual framework derived from the theory. Guevara was fiercely loyal to his cause, at the expense of the lives of many Cuban citizens as well as his own family, whom he spent little time with. He justified this with his firmly held belief that the end justified the means and that he was always fighting for the greater good. He quite literally dedicated his life to his cause, which is the reason that he has become a modern day symbol for revolution. It is however unfortunate that this came at such a great personal expense.
- Full Text:
- Date Issued: 2010
An analysis of the suitability of prescribed geography textbooks for Ciskei pupils in standard 6
- Authors: Rulashe, Turbner Mnyamezeli
- Date: 1995
- Subjects: Geography -- Study and teaching (Secondary) -- South Africa -- Eastern Cape -- Textbooks -- Evaluation
- Language: English
- Type: Thesis , Masters , MEd
- Identifier: vital:1422 , http://hdl.handle.net/10962/d1003303
- Description: Research has shown that in the South African school context textbooks are perceived as the most important guide to subject content. It is essential, therefore, that pupils and teachers should possess skills and strategies that they can use to interpret and understand the textbook. Equally, textbook writers ought to be aware of the cues pupils need to facilitate the learning process. Problems that hinder the learning of geography subject content from textbooks may arise from, among other things, the style in which the text is written, the way in which concepts are developed, the presentation of visual materials and elements of bias and stereotyping. This study scrutinises and analyses two standard 6 geography textbooks prescribed for Ciskei schools to assess the extent to which these textbooks consider the language competence of the pupils, explain and develop concepts, and in general promote the geographical education. Interviews with Ciskei teachers revealed that Standard 6 pupils encounter difficulties in the geography textbooks which are attributed to the fact that they are second language learners and they lack the requisite skills for interpreting visual materials. The analysis of the textbooks revealed that despite efforts made in recent years to rectify the most blatant aspects of bias and stereotyping and to improve the presentation of textbooks, a number of serious problems continue to exist particularly with regard to the Standard 6 learner of geography. The study attempts to alert writers of texbooks and teachers to factors which need to be taken into consideration to assist second language speakers toward effective learning.
- Full Text:
- Date Issued: 1995
- Authors: Rulashe, Turbner Mnyamezeli
- Date: 1995
- Subjects: Geography -- Study and teaching (Secondary) -- South Africa -- Eastern Cape -- Textbooks -- Evaluation
- Language: English
- Type: Thesis , Masters , MEd
- Identifier: vital:1422 , http://hdl.handle.net/10962/d1003303
- Description: Research has shown that in the South African school context textbooks are perceived as the most important guide to subject content. It is essential, therefore, that pupils and teachers should possess skills and strategies that they can use to interpret and understand the textbook. Equally, textbook writers ought to be aware of the cues pupils need to facilitate the learning process. Problems that hinder the learning of geography subject content from textbooks may arise from, among other things, the style in which the text is written, the way in which concepts are developed, the presentation of visual materials and elements of bias and stereotyping. This study scrutinises and analyses two standard 6 geography textbooks prescribed for Ciskei schools to assess the extent to which these textbooks consider the language competence of the pupils, explain and develop concepts, and in general promote the geographical education. Interviews with Ciskei teachers revealed that Standard 6 pupils encounter difficulties in the geography textbooks which are attributed to the fact that they are second language learners and they lack the requisite skills for interpreting visual materials. The analysis of the textbooks revealed that despite efforts made in recent years to rectify the most blatant aspects of bias and stereotyping and to improve the presentation of textbooks, a number of serious problems continue to exist particularly with regard to the Standard 6 learner of geography. The study attempts to alert writers of texbooks and teachers to factors which need to be taken into consideration to assist second language speakers toward effective learning.
- Full Text:
- Date Issued: 1995
Deploying DNSSEC in islands of security
- Authors: Murisa, Wesley Vengayi
- Date: 2013 , 2013-03-31
- Subjects: Internet domain names , Computer security , Computer network protocols , Computer security -- Africa
- Language: English
- Type: Thesis , Masters , MSc
- Identifier: vital:4577 , http://hdl.handle.net/10962/d1003053 , Internet domain names , Computer security , Computer network protocols , Computer security -- Africa
- Description: The Domain Name System (DNS), a name resolution protocol is one of the vulnerable network protocols that has been subjected to many security attacks such as cache poisoning, denial of service and the 'Kaminsky' spoofing attack. When DNS was designed, security was not incorporated into its design. The DNS Security Extensions (DNSSEC) provides security to the name resolution process by using public key cryptosystems. Although DNSSEC has backward compatibility with unsecured zones, it only offers security to clients when communicating with security aware zones. Widespread deployment of DNSSEC is therefore necessary to secure the name resolution process and provide security to the Internet. Only a few Top Level Domains (TLD's) have deployed DNSSEC, this inherently makes it difficult for their sub-domains to implement the security extensions to the DNS. This study analyses mechanisms that can be used by domains in islands of security to deploy DNSSEC so that the name resolution process can be secured in two specific cases where either the TLD is not signed or the domain registrar is not able to support signed domains. The DNS client side mechanisms evaluated in this study include web browser plug-ins, local validating resolvers and domain look-aside validation. The results of the study show that web browser plug-ins cannot work on their own without local validating resolvers. The web browser validators, however, proved to be useful in indicating to the user whether a domain has been validated or not. Local resolvers present a more secure option for Internet users who cannot trust the communication channel between their stub resolvers and remote name servers. However, they do not provide a way of showing the user whether a domain name has been correctly validated or not. Based on the results of the tests conducted, it is recommended that local validators be used with browser validators for visibility and improved security. On the DNS server side, Domain Look-aside Validation (DLV) presents a viable alternative for organizations in islands of security like most countries in Africa where only two country code Top Level Domains (ccTLD) have deployed DNSSEC. This research recommends use of DLV by corporates to provide DNS security to both internal and external users accessing their web based services. , LaTeX with hyperref package , pdfTeX-1.40.10
- Full Text:
- Date Issued: 2013
- Authors: Murisa, Wesley Vengayi
- Date: 2013 , 2013-03-31
- Subjects: Internet domain names , Computer security , Computer network protocols , Computer security -- Africa
- Language: English
- Type: Thesis , Masters , MSc
- Identifier: vital:4577 , http://hdl.handle.net/10962/d1003053 , Internet domain names , Computer security , Computer network protocols , Computer security -- Africa
- Description: The Domain Name System (DNS), a name resolution protocol is one of the vulnerable network protocols that has been subjected to many security attacks such as cache poisoning, denial of service and the 'Kaminsky' spoofing attack. When DNS was designed, security was not incorporated into its design. The DNS Security Extensions (DNSSEC) provides security to the name resolution process by using public key cryptosystems. Although DNSSEC has backward compatibility with unsecured zones, it only offers security to clients when communicating with security aware zones. Widespread deployment of DNSSEC is therefore necessary to secure the name resolution process and provide security to the Internet. Only a few Top Level Domains (TLD's) have deployed DNSSEC, this inherently makes it difficult for their sub-domains to implement the security extensions to the DNS. This study analyses mechanisms that can be used by domains in islands of security to deploy DNSSEC so that the name resolution process can be secured in two specific cases where either the TLD is not signed or the domain registrar is not able to support signed domains. The DNS client side mechanisms evaluated in this study include web browser plug-ins, local validating resolvers and domain look-aside validation. The results of the study show that web browser plug-ins cannot work on their own without local validating resolvers. The web browser validators, however, proved to be useful in indicating to the user whether a domain has been validated or not. Local resolvers present a more secure option for Internet users who cannot trust the communication channel between their stub resolvers and remote name servers. However, they do not provide a way of showing the user whether a domain name has been correctly validated or not. Based on the results of the tests conducted, it is recommended that local validators be used with browser validators for visibility and improved security. On the DNS server side, Domain Look-aside Validation (DLV) presents a viable alternative for organizations in islands of security like most countries in Africa where only two country code Top Level Domains (ccTLD) have deployed DNSSEC. This research recommends use of DLV by corporates to provide DNS security to both internal and external users accessing their web based services. , LaTeX with hyperref package , pdfTeX-1.40.10
- Full Text:
- Date Issued: 2013
An investigation of the polarization of solar radio noise
- Authors: Verschuur, Gerrit L.,1937-
- Date: 1961
- Subjects: Solar radio emission , Polarimetry
- Language: English
- Type: Thesis , Masters , MSc
- Identifier: vital:5547 , http://hdl.handle.net/10962/d1013441
- Description: CHAPTER I A description of the sun and the type of radio radiation it emits is given. The relation that exists between this and other events occurring on the sun's surface is studied. CHAPTER II The literature dealing with the origin of solar radio noise is reviewed. CHAPTER III The method of specifying polarized radiation and the effect of a magneto- ionic medium on such radiation is discussed. The possible origin of the polarization of solar radio noise is examined and the literature relating to this and to the observations of polarization of solar noise is reviewed. A short outline of the methods used in measuring polarization is given. CHAPTER IV A detailed outline of the construction of a polarimeter is given together with full circuit diagrams and illustrative photographs. CHAPTER V A brief discussion of the operation of the polarimeter, the results obtained and suggestions for its future operation is given.
- Full Text:
- Date Issued: 1961
- Authors: Verschuur, Gerrit L.,1937-
- Date: 1961
- Subjects: Solar radio emission , Polarimetry
- Language: English
- Type: Thesis , Masters , MSc
- Identifier: vital:5547 , http://hdl.handle.net/10962/d1013441
- Description: CHAPTER I A description of the sun and the type of radio radiation it emits is given. The relation that exists between this and other events occurring on the sun's surface is studied. CHAPTER II The literature dealing with the origin of solar radio noise is reviewed. CHAPTER III The method of specifying polarized radiation and the effect of a magneto- ionic medium on such radiation is discussed. The possible origin of the polarization of solar radio noise is examined and the literature relating to this and to the observations of polarization of solar noise is reviewed. A short outline of the methods used in measuring polarization is given. CHAPTER IV A detailed outline of the construction of a polarimeter is given together with full circuit diagrams and illustrative photographs. CHAPTER V A brief discussion of the operation of the polarimeter, the results obtained and suggestions for its future operation is given.
- Full Text:
- Date Issued: 1961
The mode of action of the acyl-diethylamide molluscicides
- Authors: Solomon, Keith Ross
- Date: 1971
- Subjects: Pesticides , Molluscicides
- Language: English
- Type: Thesis , Masters , MSc
- Identifier: vital:5821 , http://hdl.handle.net/10962/d1007406
- Description: From Introduction: That bilharziasis an important public health, social and economic problem in the tropical and subtropical countries of the world is well appreciated. (WHO, 1965) Bilharsiasis is the disease caused by parasitic worms of the genus Schistosoma having certain fresh water snails as the intermediate host. In South Africa the more important snails are Bulinus africanus and B. globosus, the secondary hosts of Schistosom haematobium. (WHO, 1965) One method of controling the disease is to reduce the numbers of the intermediate host snails to such a low level that transmission cannot occur (WHO, 1965 and Macdonald, 1965) This has led to a strong interest in those substances that kill snails. The first recorded use of a molluscicide, copper sulphate, was during the first world War in Egypt. (De Villiers, 1965) More recently, the more or less random testing of large numbers of compounds led to the discovery of a large number of molluscicides. These were the heavy metal compounds such as the salts of mercury and arsenic, the substituted phenols such as pentachlorophenol (PCP) and the 2-substituted 4:6-dinitrophenols. (De Villiers, 1965) These compounds are good molluscicides but suffer from a number of disadvantages. The use of copper compounds in hard waters is impractical as the copper precipitates out as the less effective carbonate. The heavy metal salts are expensive and biocidal thus making the treated water unsuitable for human or agricultural use. The phenolic compounds are unpleasant and dangerous to handle and the hydrolysis of PCP is catalysed by sunlight in clear waters. High concentrations of these compounds are required, thus increasing transport and handling costs, particularly in inaccessible areas.
- Full Text:
- Date Issued: 1971
- Authors: Solomon, Keith Ross
- Date: 1971
- Subjects: Pesticides , Molluscicides
- Language: English
- Type: Thesis , Masters , MSc
- Identifier: vital:5821 , http://hdl.handle.net/10962/d1007406
- Description: From Introduction: That bilharziasis an important public health, social and economic problem in the tropical and subtropical countries of the world is well appreciated. (WHO, 1965) Bilharsiasis is the disease caused by parasitic worms of the genus Schistosoma having certain fresh water snails as the intermediate host. In South Africa the more important snails are Bulinus africanus and B. globosus, the secondary hosts of Schistosom haematobium. (WHO, 1965) One method of controling the disease is to reduce the numbers of the intermediate host snails to such a low level that transmission cannot occur (WHO, 1965 and Macdonald, 1965) This has led to a strong interest in those substances that kill snails. The first recorded use of a molluscicide, copper sulphate, was during the first world War in Egypt. (De Villiers, 1965) More recently, the more or less random testing of large numbers of compounds led to the discovery of a large number of molluscicides. These were the heavy metal compounds such as the salts of mercury and arsenic, the substituted phenols such as pentachlorophenol (PCP) and the 2-substituted 4:6-dinitrophenols. (De Villiers, 1965) These compounds are good molluscicides but suffer from a number of disadvantages. The use of copper compounds in hard waters is impractical as the copper precipitates out as the less effective carbonate. The heavy metal salts are expensive and biocidal thus making the treated water unsuitable for human or agricultural use. The phenolic compounds are unpleasant and dangerous to handle and the hydrolysis of PCP is catalysed by sunlight in clear waters. High concentrations of these compounds are required, thus increasing transport and handling costs, particularly in inaccessible areas.
- Full Text:
- Date Issued: 1971
The principle of complementarity : a critical analysis of Article 17 of the Rome Statute from an African perspective
- Authors: Mohami, Thapelo Adelice
- Date: 2014
- Subjects: Complementarity (International law) , Rome Statute of the International Criminal Court (1998 July 17) , International Criminal Court , Criminal jurisdiction -- Africa , International crimes -- Africa , Crimes against humanity -- Africa
- Language: English
- Type: Thesis , Masters , LLM
- Identifier: vital:3720 , http://hdl.handle.net/10962/d1013326
- Description: This thesis attempts to address perennial concerns, mostly raised in some quarters in Africa, pertaining to the development of the complementarity regime established by the Rome Statute of the International Criminal Court. It grapples with a very important question, whether the principle of complementarity, embodied in article 17 of the Rome Statute, was formulated and is being applied by the ICC in a manner that upholds the ideals and theories upon which the regime was founded. The principle of complementarity is designed to mediate the imperatives of State sovereignty and a legitimate international criminal justice system. Essentially, complementarity gives States latitude to try genocide, crimes against humanity, war crimes and aggression nationally, with the ICC only intervening where States are either unable or unwilling to prosecute genuinely. Africa constitutes the biggest regional block of membership to the Rome Statute, however, over the years; support for the ICC on the African continent has waned. It has been argued in some quarters that the ICC is anti-African and that it has interpreted and applied complementarity in a manner that diminishes State sovereignty. The thesis argues that this tension may also be due to textual deficiencies inherent within the Rome Statute, in the provisions that embody this principle. It therefore examines complementarity from a theoretical perspective to provide a comprehensive account of the system contemplated by the drafters of the Rome Statute. In this regard, the thesis argues for expansion of States’ ability at the national level to deal with international crimes without compromising international criminal justice processes or threatening State sovereignty. This is suggested as a way of relieving the tension that has characterised the relationship between African States and the ICC. The thesis further sketches out some of the complexities inherent in the modalities through which the Court may exercise its complementary jurisdiction, particularly within the African continent, given that legal systems in most African countries are particularly weak. It thus dissects the provisions that outline the principle of complementarity in tandem with the Court’s interpretation and application of complementarity in practice. Furthermore, through an exploratory survey of the referral of the Situation in Uganda, and the ICC Prosecutor’s proprio motu investigation of the Situation in Kenya, the thesis illustrates how a positive approach to complementarity can help establish a healthy cooperative synergy between the ICC and States, thereby promoting a functional expeditious criminal justice system. This will go a long way towards assuaging State’s fears that the ICC merely pays lip service to complementarity and arbitrarily supersedes national jurisdiction.
- Full Text:
- Date Issued: 2014
- Authors: Mohami, Thapelo Adelice
- Date: 2014
- Subjects: Complementarity (International law) , Rome Statute of the International Criminal Court (1998 July 17) , International Criminal Court , Criminal jurisdiction -- Africa , International crimes -- Africa , Crimes against humanity -- Africa
- Language: English
- Type: Thesis , Masters , LLM
- Identifier: vital:3720 , http://hdl.handle.net/10962/d1013326
- Description: This thesis attempts to address perennial concerns, mostly raised in some quarters in Africa, pertaining to the development of the complementarity regime established by the Rome Statute of the International Criminal Court. It grapples with a very important question, whether the principle of complementarity, embodied in article 17 of the Rome Statute, was formulated and is being applied by the ICC in a manner that upholds the ideals and theories upon which the regime was founded. The principle of complementarity is designed to mediate the imperatives of State sovereignty and a legitimate international criminal justice system. Essentially, complementarity gives States latitude to try genocide, crimes against humanity, war crimes and aggression nationally, with the ICC only intervening where States are either unable or unwilling to prosecute genuinely. Africa constitutes the biggest regional block of membership to the Rome Statute, however, over the years; support for the ICC on the African continent has waned. It has been argued in some quarters that the ICC is anti-African and that it has interpreted and applied complementarity in a manner that diminishes State sovereignty. The thesis argues that this tension may also be due to textual deficiencies inherent within the Rome Statute, in the provisions that embody this principle. It therefore examines complementarity from a theoretical perspective to provide a comprehensive account of the system contemplated by the drafters of the Rome Statute. In this regard, the thesis argues for expansion of States’ ability at the national level to deal with international crimes without compromising international criminal justice processes or threatening State sovereignty. This is suggested as a way of relieving the tension that has characterised the relationship between African States and the ICC. The thesis further sketches out some of the complexities inherent in the modalities through which the Court may exercise its complementary jurisdiction, particularly within the African continent, given that legal systems in most African countries are particularly weak. It thus dissects the provisions that outline the principle of complementarity in tandem with the Court’s interpretation and application of complementarity in practice. Furthermore, through an exploratory survey of the referral of the Situation in Uganda, and the ICC Prosecutor’s proprio motu investigation of the Situation in Kenya, the thesis illustrates how a positive approach to complementarity can help establish a healthy cooperative synergy between the ICC and States, thereby promoting a functional expeditious criminal justice system. This will go a long way towards assuaging State’s fears that the ICC merely pays lip service to complementarity and arbitrarily supersedes national jurisdiction.
- Full Text:
- Date Issued: 2014
The role of civil society in advancing education rights : the case of Gadra Education, Grahamstown, South Africa
- Authors: Msindo, Esteri Makotore
- Date: 2015
- Subjects: Gadra Education (Grahamstown, South Africa) , Right to education -- South Africa , State departments of education -- South Africa , Educational change -- South Africa , Social justice -- South Africa , Civil society -- South Africa , Social contract
- Language: English
- Type: Thesis , Masters , MSocSc
- Identifier: vital:3392 , http://hdl.handle.net/10962/d1016500
- Description: This thesis has identified and analysed the role of an NGO called Gadra Education in advancing education rights to the less advantaged people of Grahamstown in South Africa. Gadra Education’s role has been identified as twofold. Firstly as an educational NGO, Gadra Education’s initiatives directly impact on the lives of the less economically and socially privileged learners who, due to their previous learning environment in state schools, do not achieve academic results that ensure entry into tertiary level. Secondly its role is identified in its nature as an organisation that emerged due to the deficiencies in the state schooling system. It therefore stands de facto as a critical institution for critique of the state’s education system. The thesis concludes that without confronting the Department of Education or collaborating with it, Gadra Education offers a significant alternative approach which can potentially influence the state to improve the state schooling system. Its strategy of non-confrontation to the state, informal and non-corporatist is advantageous as an NGO that focuses on the actual provision of education. It focuses on instilling Ubuntu values of sharing and giving that are of critical significance in teaching and learning. The context of the thesis is located broadly within socio-economic rights and specifically on education rights. In South Africa where the state has not adequately met the educational obligations for the economically and socially less privileged citizens, the emergence of educational NGOs that focus on providing education to the poor is of vital importance. Although other NGOs that confront the state are important in pushing the state to deliver especially on school infrastructure, teacher deployment and other educational challenges, Gadra Education model ensures academic success for the learner. Lessons can be drawn from Gadra Education which can be potentially useful to state schools and other NGOs that seek to advance education rights to disadvantaged communities.
- Full Text:
- Date Issued: 2015
- Authors: Msindo, Esteri Makotore
- Date: 2015
- Subjects: Gadra Education (Grahamstown, South Africa) , Right to education -- South Africa , State departments of education -- South Africa , Educational change -- South Africa , Social justice -- South Africa , Civil society -- South Africa , Social contract
- Language: English
- Type: Thesis , Masters , MSocSc
- Identifier: vital:3392 , http://hdl.handle.net/10962/d1016500
- Description: This thesis has identified and analysed the role of an NGO called Gadra Education in advancing education rights to the less advantaged people of Grahamstown in South Africa. Gadra Education’s role has been identified as twofold. Firstly as an educational NGO, Gadra Education’s initiatives directly impact on the lives of the less economically and socially privileged learners who, due to their previous learning environment in state schools, do not achieve academic results that ensure entry into tertiary level. Secondly its role is identified in its nature as an organisation that emerged due to the deficiencies in the state schooling system. It therefore stands de facto as a critical institution for critique of the state’s education system. The thesis concludes that without confronting the Department of Education or collaborating with it, Gadra Education offers a significant alternative approach which can potentially influence the state to improve the state schooling system. Its strategy of non-confrontation to the state, informal and non-corporatist is advantageous as an NGO that focuses on the actual provision of education. It focuses on instilling Ubuntu values of sharing and giving that are of critical significance in teaching and learning. The context of the thesis is located broadly within socio-economic rights and specifically on education rights. In South Africa where the state has not adequately met the educational obligations for the economically and socially less privileged citizens, the emergence of educational NGOs that focus on providing education to the poor is of vital importance. Although other NGOs that confront the state are important in pushing the state to deliver especially on school infrastructure, teacher deployment and other educational challenges, Gadra Education model ensures academic success for the learner. Lessons can be drawn from Gadra Education which can be potentially useful to state schools and other NGOs that seek to advance education rights to disadvantaged communities.
- Full Text:
- Date Issued: 2015
Characterization of chromatic dispersion in single mode fibre
- Authors: Wassin, Shukree
- Date: 2014
- Subjects: Fiber optics Electromagnetic waves , Electromagnetic waves -- Transmission
- Language: English
- Type: Thesis , Masters , MSc
- Identifier: http://hdl.handle.net/10948/47807 , vital:40379
- Description: In this dissertation, an investigation of chromatic dispersion is presented. The Pulse delay and phase Shift chromatic dispersion characterization techniques were used for conducting the measurements. The experiments were performed in a modern optical fibre research laboratory and chromatic dispersion measurements were carried out on several lengths of G.652 and G.655 single mode fibres. The pulse delay characterization technique measures the time of flight between two modulated optical signals whilst propagating along the fibre under test. During phase shift experiments, the group delay is obtained by measuring the relative phase difference as a function of wavelength, between adjacent sinusoidal light signals. The pulse delay and phase shift characterization techniques illustrated excellent agreement in the measured! chromatic Dispersion coefficients along the G.652 standard single mode! fibre as well as the G.655 positive and negative non-zero dispersion shifted fibre. It was found that the measurement accuracy improved as the fibre length increased. A periodic shift between the modulated optical signals, propagating along the fibre was experimentally observed. It is to be remarked that the longer wavelength signals propagated faster along the G.655 positive non-zero dispersion shifted fibre in comparison to its transmission within the G.655 negative non-zero dispersion shifted fibre. Furthermore, it was found that the sinusoidal signal shifted towards the left along the G.655 negative NZDSF fibre whilst the shift occurred towards the right along the G.655 positive NZDSF fibre. Generally, the shift arising along the G.655 fibres was found to be smaller than the shift seen throughout the G.652 fibres. Towards the end of this study, a chromatic dispersion compensation system was designed and tested. Once characterization of the compensation link was completed, it was experimentally illustrated that the chromatic dispersion across the system was successfully reduced. Finally, a sum of squares of error statistical test showed that the phase shift technique is more accurate in comparison to the pulse delay method. This result was found to be in good agreement with published work found in literature.
- Full Text:
- Date Issued: 2014
- Authors: Wassin, Shukree
- Date: 2014
- Subjects: Fiber optics Electromagnetic waves , Electromagnetic waves -- Transmission
- Language: English
- Type: Thesis , Masters , MSc
- Identifier: http://hdl.handle.net/10948/47807 , vital:40379
- Description: In this dissertation, an investigation of chromatic dispersion is presented. The Pulse delay and phase Shift chromatic dispersion characterization techniques were used for conducting the measurements. The experiments were performed in a modern optical fibre research laboratory and chromatic dispersion measurements were carried out on several lengths of G.652 and G.655 single mode fibres. The pulse delay characterization technique measures the time of flight between two modulated optical signals whilst propagating along the fibre under test. During phase shift experiments, the group delay is obtained by measuring the relative phase difference as a function of wavelength, between adjacent sinusoidal light signals. The pulse delay and phase shift characterization techniques illustrated excellent agreement in the measured! chromatic Dispersion coefficients along the G.652 standard single mode! fibre as well as the G.655 positive and negative non-zero dispersion shifted fibre. It was found that the measurement accuracy improved as the fibre length increased. A periodic shift between the modulated optical signals, propagating along the fibre was experimentally observed. It is to be remarked that the longer wavelength signals propagated faster along the G.655 positive non-zero dispersion shifted fibre in comparison to its transmission within the G.655 negative non-zero dispersion shifted fibre. Furthermore, it was found that the sinusoidal signal shifted towards the left along the G.655 negative NZDSF fibre whilst the shift occurred towards the right along the G.655 positive NZDSF fibre. Generally, the shift arising along the G.655 fibres was found to be smaller than the shift seen throughout the G.652 fibres. Towards the end of this study, a chromatic dispersion compensation system was designed and tested. Once characterization of the compensation link was completed, it was experimentally illustrated that the chromatic dispersion across the system was successfully reduced. Finally, a sum of squares of error statistical test showed that the phase shift technique is more accurate in comparison to the pulse delay method. This result was found to be in good agreement with published work found in literature.
- Full Text:
- Date Issued: 2014