Perceptions and experiences of G2E e-Government workplace restructuring: The cases of Buffalo City and City of Cape Town metropolitan municipalities, South Africa
- Authors: Makwembere, Sandra
- Date: 2016
- Language: English
- Type: Thesis , Doctoral , PhD
- Identifier: http://hdl.handle.net/10962/617 , vital:19975
- Description: Taking the cases of Buffalo City Metropolitan municipality (BCMM) and City of Cape Town Metropolitan municipality (CoCT), this thesis explores the implications of government to employee (G2E) electronic government workplace restructuring on skills transformation and workplace control as perceived by back office employees and managers from different Corporate Services departments. It aims to describe the arrangements, rationale and degree of G2E e-government at BCMM and CoCT, investigate how managers, employees and union representatives identify the workplace changes relating to skill as well as document and analyse workplace struggles linked to G2E e-government. Using labour process analysis, the impacts of G2E e-government technological change are conceptualised. The labour process concepts alert us to ways in which G2E e-government technology is applied in the context of specific public sector production relations. They explain how employees and managers experience the dynamics of skill transformation and the mechanisms of control related to G2E e-government. The consideration of the labour process contrasts predominant e-government scholarly works that focus on government websites. Further, by using case study methods, namely interviews, surveys and observations, the thesis documents the particular back office employees’ and managers’ realities of G2E e-government which are marginalised in scholarly literature. The sample of respondents were selected using purposive sampling based on the subjects’ knowledge and experience, snowball sampling following referrals and random sampling during site visits. The respondents included four managers, four employees, two shop stewards and one service provider at BCMM and 16 managers, 20 employees and four shop stewards at CoCT. The findings from BCMM and CoCT illustrate how G2E e-government workplace restructuring individualises the labour process through the kind of technologies it introduces. Moreover, they show how the restructuring facilitates electronic information, communication and operations which broaden demands on technical as well as social skills. The findings also show that the restructuring extends avenues for managerial control thereby marginalising union representivity as the workplace control systems create opportunities for systemic control by management. As the South African government adopts electronic government and makes optimistic declarations of “cost saving”, “efficiency”, “productivity” and “innovation” through egovernment, the study uncovers marginalised local government employee and manager experiences. It contributes to building new knowledge on the impacts of contemporary technological change on the local government labour process and contributes to debates around the effects of G2E e-government reforms on local government.
- Full Text:
- Authors: Makwembere, Sandra
- Date: 2016
- Language: English
- Type: Thesis , Doctoral , PhD
- Identifier: http://hdl.handle.net/10962/617 , vital:19975
- Description: Taking the cases of Buffalo City Metropolitan municipality (BCMM) and City of Cape Town Metropolitan municipality (CoCT), this thesis explores the implications of government to employee (G2E) electronic government workplace restructuring on skills transformation and workplace control as perceived by back office employees and managers from different Corporate Services departments. It aims to describe the arrangements, rationale and degree of G2E e-government at BCMM and CoCT, investigate how managers, employees and union representatives identify the workplace changes relating to skill as well as document and analyse workplace struggles linked to G2E e-government. Using labour process analysis, the impacts of G2E e-government technological change are conceptualised. The labour process concepts alert us to ways in which G2E e-government technology is applied in the context of specific public sector production relations. They explain how employees and managers experience the dynamics of skill transformation and the mechanisms of control related to G2E e-government. The consideration of the labour process contrasts predominant e-government scholarly works that focus on government websites. Further, by using case study methods, namely interviews, surveys and observations, the thesis documents the particular back office employees’ and managers’ realities of G2E e-government which are marginalised in scholarly literature. The sample of respondents were selected using purposive sampling based on the subjects’ knowledge and experience, snowball sampling following referrals and random sampling during site visits. The respondents included four managers, four employees, two shop stewards and one service provider at BCMM and 16 managers, 20 employees and four shop stewards at CoCT. The findings from BCMM and CoCT illustrate how G2E e-government workplace restructuring individualises the labour process through the kind of technologies it introduces. Moreover, they show how the restructuring facilitates electronic information, communication and operations which broaden demands on technical as well as social skills. The findings also show that the restructuring extends avenues for managerial control thereby marginalising union representivity as the workplace control systems create opportunities for systemic control by management. As the South African government adopts electronic government and makes optimistic declarations of “cost saving”, “efficiency”, “productivity” and “innovation” through egovernment, the study uncovers marginalised local government employee and manager experiences. It contributes to building new knowledge on the impacts of contemporary technological change on the local government labour process and contributes to debates around the effects of G2E e-government reforms on local government.
- Full Text:
Selecting and augmenting a FOSS development and deployment environment for personalized video-oriented services in a Telco context
- Authors: Shibeshi, Zelalem Sintayehu
- Date: 2016
- Language: English
- Type: Thesis , Doctoral , PhD
- Identifier: http://hdl.handle.net/10962/943 , vital:20005
- Description: The great demand for video services on the Internet is one contributing factor that led telecom companies to search for solutions to deliver innovative video services, using the different access technologies managed by them and leveraging the capacity of enforcing Quality of Service (QoS). One part of the solution was an infrastructure that guarantees QoS for these services, in the form of the IP Multimedia Subsystem (IMS) framework. The IMS framework was developed for delivering innovative multimedia services, but IMS alone does not provide the required services. This has led to further work in the area of multimedia service architectures. One noteworthy architecture is IPTV. IPTV is more than what its name implies, as it allows the development of various innovative video-oriented services and not just tv. When IPTV was introduced, many thought that it would bring back the revenue loss that telecom companies experienced to over-the-top (OTT) service providers. However, despite all its promises, the IPTV implementation has not shown as wide an uptake as one would expect. Although there could be various reasons for the slow penetration of IPTV, one reason could be the technical challenge that IPTV poses to service developers. One of the main reasons for the embarking of the research reported in this thesis was to identify and select free and open source software (FOSS) based platforms and augment them for easy development and deployment of video-oriented services. The thesis motivated how the IPTV architecture, with some modification, can be a good architecture to develop innovative video-oriented services. For a better understanding and investigate the issues of video-oriented service development on different platforms, we followed an incremental and iterative prototyping method. As a result, various video-oriented services were first developed and implementation-related issues were analyzed. This has helped us to identify problems that service developers face, including the requirement to utilize a number of protocols to develop an IPTV-based video-oriented service and the lack of a platform that provides a consistent programming interface to implement them all. The process also helped us to identify new uses cases through the process. As part of our selection process, we found that the Mobicents service development platform can be used as the basis for a good service development and deployment environment for video-oriented services. Mobicents is a Java-based service delivery platform for quick development, deployment and management of next generation network applications. Mobicents is a good choice because it provides a consistent programming interface and supports the various protocols needed in a consistent manner or an easy way to include the support for them. We used Mobicents to compose the environment that developers can use to build video-oriented services. Specifically we developed components and service building blocks that service developer can use to develop various innovative video-oriented services. During our research, we also identified various issues with regard to support from streaming servers in general and open source streaming servers in particular and also with the protocol they use. Specifically, we identified issues with Real Time Streaming Protocol (RTSP), a protocol specified as the media control protocol in the IPTV specification, and made proposals for solving them. We developed an RSTP proxy to augment the features lacking in the current streaming servers and implemented some of the features we proposed in it.
- Full Text:
- Authors: Shibeshi, Zelalem Sintayehu
- Date: 2016
- Language: English
- Type: Thesis , Doctoral , PhD
- Identifier: http://hdl.handle.net/10962/943 , vital:20005
- Description: The great demand for video services on the Internet is one contributing factor that led telecom companies to search for solutions to deliver innovative video services, using the different access technologies managed by them and leveraging the capacity of enforcing Quality of Service (QoS). One part of the solution was an infrastructure that guarantees QoS for these services, in the form of the IP Multimedia Subsystem (IMS) framework. The IMS framework was developed for delivering innovative multimedia services, but IMS alone does not provide the required services. This has led to further work in the area of multimedia service architectures. One noteworthy architecture is IPTV. IPTV is more than what its name implies, as it allows the development of various innovative video-oriented services and not just tv. When IPTV was introduced, many thought that it would bring back the revenue loss that telecom companies experienced to over-the-top (OTT) service providers. However, despite all its promises, the IPTV implementation has not shown as wide an uptake as one would expect. Although there could be various reasons for the slow penetration of IPTV, one reason could be the technical challenge that IPTV poses to service developers. One of the main reasons for the embarking of the research reported in this thesis was to identify and select free and open source software (FOSS) based platforms and augment them for easy development and deployment of video-oriented services. The thesis motivated how the IPTV architecture, with some modification, can be a good architecture to develop innovative video-oriented services. For a better understanding and investigate the issues of video-oriented service development on different platforms, we followed an incremental and iterative prototyping method. As a result, various video-oriented services were first developed and implementation-related issues were analyzed. This has helped us to identify problems that service developers face, including the requirement to utilize a number of protocols to develop an IPTV-based video-oriented service and the lack of a platform that provides a consistent programming interface to implement them all. The process also helped us to identify new uses cases through the process. As part of our selection process, we found that the Mobicents service development platform can be used as the basis for a good service development and deployment environment for video-oriented services. Mobicents is a Java-based service delivery platform for quick development, deployment and management of next generation network applications. Mobicents is a good choice because it provides a consistent programming interface and supports the various protocols needed in a consistent manner or an easy way to include the support for them. We used Mobicents to compose the environment that developers can use to build video-oriented services. Specifically we developed components and service building blocks that service developer can use to develop various innovative video-oriented services. During our research, we also identified various issues with regard to support from streaming servers in general and open source streaming servers in particular and also with the protocol they use. Specifically, we identified issues with Real Time Streaming Protocol (RTSP), a protocol specified as the media control protocol in the IPTV specification, and made proposals for solving them. We developed an RSTP proxy to augment the features lacking in the current streaming servers and implemented some of the features we proposed in it.
- Full Text:
Field and laboratory analyses of manual tasks in the South African automotive industry
- Authors: James, Jonathan Peter
- Date: 2007
- Subjects: Automobile industry and trade -- South Africa -- Safety measures , Human engineering -- South Africa , Automobile industry workers -- South Africa -- Health risk assessment , Industrial safety -- South Africa
- Language: English
- Type: Thesis , Doctoral , PhD
- Identifier: vital:5121 , http://hdl.handle.net/10962/d1005199 , Automobile industry and trade -- South Africa -- Safety measures , Human engineering -- South Africa , Automobile industry workers -- South Africa -- Health risk assessment , Industrial safety -- South Africa
- Description: The present study adopted a “field-laboratory-field” approach in the assessment of the efficacy of ergonomics interventions specific to two selected tasks evaluated in a South African automotive industry. Initial field testing was conducted in an Eastern Cape (South Africa) automotive plant where high risk areas were identified during walkthrough ergonomics surveys in conjunction with interaction with operators. Temporal factors and working postures of 12 industrial workers were recorded and observed, while physiological and perceptual responses were assessed. Two priority areas were focused upon for analysis, namely the Paintshop and Bodyshop with the former identified as being the more taxing of the two tasks. Responses of 30 students participating in rigourously controlled laboratory simulations were subsequently collected while completing the two tasks, namely the Paintshop Trolley Transfer (PTT) and Car Door Carriage (CDC) for participants. Working postures, kinematic, physiological and perceptual responses were assessed pre- and post-intervention. Following the laboratory experimentation a basic re-evaluation was conducted at the plant to assess whether the proposed changes had a positive effect on working postures, physiological and perceptual responses. The results of the preliminary field investigation revealed a prevalence of awkward working postures and excessive manual work in both areas. Laboratory experimentation revealed a notable reduction in task demands pre- versus post-intervention. The PTT mean lean angle for two-handed pre-intervention pulling observations of 23.7° (±3.51) was reduced to 13.9° (±2.21) post-intervention. Low back disorder (LBD) risk was reduced during the two-handed pull intervention (from 36.8% ±8.03 to 21.7% ±5.31). A significant decrement in heart rate responses from 103 bt.min-1 (±11.62) to 93 bt.min[superscript -1] (±11.77) was recorded during the two-handed symmetrical pushing intervention. The electromyography (EMG) responses for one-handed pushing and pulling pre-intervention showed the highest levels of muscular activity in the right medial deltoid due to an awkward and asymmetrical posture. CDC responses demonstrated that minor changes in the storage height of the door resulted in a significant reduction in sagittal flexion from 28.0° (±4.78) to 20.7° (±5.65). Predictions of average probability of LBD risk were significantly reduced from 50.3% (±5.91) to 39.8% (±5.10) for post-intervention car door lifting. In addition, the greatest reduction in EMG activity as a %MVC was achieved during sub-task ii (reduced from 35.1 to 13.7% and 30.5 to 13.9% for left and right erector spinae respectively) which was associated with the introduction of the transfer trolley for the door transfer phase of the CDC. Re-evaluation in the automotive plant revealed that the most notable change has been the implementation of automated ride on trolleys in the Paintshop. The Bodyshop area has also been modified to allow more effective job rotation and the step into the storage bin has been reduced via a “low-cost” stepping platform. Mean heart rate recordings were reduced from 94 (±9.77) bt.min[superscript -1] to 81 (±3.72) bt.min[superscript -1] in the Paintshop. Overall the results demonstrate the effect of “low-cost” interventions in reducing the physical stresses placed on workers in the automotive industry where much of the work is still done manually.
- Full Text:
- Authors: James, Jonathan Peter
- Date: 2007
- Subjects: Automobile industry and trade -- South Africa -- Safety measures , Human engineering -- South Africa , Automobile industry workers -- South Africa -- Health risk assessment , Industrial safety -- South Africa
- Language: English
- Type: Thesis , Doctoral , PhD
- Identifier: vital:5121 , http://hdl.handle.net/10962/d1005199 , Automobile industry and trade -- South Africa -- Safety measures , Human engineering -- South Africa , Automobile industry workers -- South Africa -- Health risk assessment , Industrial safety -- South Africa
- Description: The present study adopted a “field-laboratory-field” approach in the assessment of the efficacy of ergonomics interventions specific to two selected tasks evaluated in a South African automotive industry. Initial field testing was conducted in an Eastern Cape (South Africa) automotive plant where high risk areas were identified during walkthrough ergonomics surveys in conjunction with interaction with operators. Temporal factors and working postures of 12 industrial workers were recorded and observed, while physiological and perceptual responses were assessed. Two priority areas were focused upon for analysis, namely the Paintshop and Bodyshop with the former identified as being the more taxing of the two tasks. Responses of 30 students participating in rigourously controlled laboratory simulations were subsequently collected while completing the two tasks, namely the Paintshop Trolley Transfer (PTT) and Car Door Carriage (CDC) for participants. Working postures, kinematic, physiological and perceptual responses were assessed pre- and post-intervention. Following the laboratory experimentation a basic re-evaluation was conducted at the plant to assess whether the proposed changes had a positive effect on working postures, physiological and perceptual responses. The results of the preliminary field investigation revealed a prevalence of awkward working postures and excessive manual work in both areas. Laboratory experimentation revealed a notable reduction in task demands pre- versus post-intervention. The PTT mean lean angle for two-handed pre-intervention pulling observations of 23.7° (±3.51) was reduced to 13.9° (±2.21) post-intervention. Low back disorder (LBD) risk was reduced during the two-handed pull intervention (from 36.8% ±8.03 to 21.7% ±5.31). A significant decrement in heart rate responses from 103 bt.min-1 (±11.62) to 93 bt.min[superscript -1] (±11.77) was recorded during the two-handed symmetrical pushing intervention. The electromyography (EMG) responses for one-handed pushing and pulling pre-intervention showed the highest levels of muscular activity in the right medial deltoid due to an awkward and asymmetrical posture. CDC responses demonstrated that minor changes in the storage height of the door resulted in a significant reduction in sagittal flexion from 28.0° (±4.78) to 20.7° (±5.65). Predictions of average probability of LBD risk were significantly reduced from 50.3% (±5.91) to 39.8% (±5.10) for post-intervention car door lifting. In addition, the greatest reduction in EMG activity as a %MVC was achieved during sub-task ii (reduced from 35.1 to 13.7% and 30.5 to 13.9% for left and right erector spinae respectively) which was associated with the introduction of the transfer trolley for the door transfer phase of the CDC. Re-evaluation in the automotive plant revealed that the most notable change has been the implementation of automated ride on trolleys in the Paintshop. The Bodyshop area has also been modified to allow more effective job rotation and the step into the storage bin has been reduced via a “low-cost” stepping platform. Mean heart rate recordings were reduced from 94 (±9.77) bt.min[superscript -1] to 81 (±3.72) bt.min[superscript -1] in the Paintshop. Overall the results demonstrate the effect of “low-cost” interventions in reducing the physical stresses placed on workers in the automotive industry where much of the work is still done manually.
- Full Text:
Biology, population dynamics and management of carpenter (Argyrozona argyrozona) an endemic South African reef fish
- Authors: Brouwer, Stephen Leonard
- Date: 2005
- Subjects: Reef fishes -- South Africa Sparidae -- South Africa
- Language: English
- Type: Thesis , Doctoral , PhD
- Identifier: vital:5241 , http://hdl.handle.net/10962/d1005084
- Description: Carpenter, Argyrozona argyrozona (Valenciennes, 1830), is an endemic South African sparid fish. They form an important component of the commercial linefishery on the South African east coast, where they are the third most important species landed. Recent investigations revealed that the catch per unit effort (cpue) of this species has declined markedly since the early 1900’s. Despite these declines and the importance of this resource, remarkably little biological information on this species exists for providing management advice. This thesis investigates the life history of carpenter, particularly those aspects that are used for management. This includes an investigation into the stock distribution and identification of nursery areas, and an assessment of age, growth, reproduction and movement patterns. Age and growth was assessed using methods based on both otoliths and mark-recapture. Transverse sagittal sections from the Tsitsikamma National Park showed clear opaque and translucent growth increments. Marginal growth zone analysis and mark-recapture of chemically tagged fish (Oxytetracycline) revealed that these were deposited on an annual basis: opaque in summer and translucent in winter. A. argyrozona were found to be long lived (up to 27 years) and slow growing. Within reader (between counts) and between readers average percent error (APE) was 5.3 and 1.8, respectively, showing that readability of carpenter otoliths is high. Comparison between whole and sectioned otoliths showed that the former significantly under-estimated the age of fish older than 10 years (p<0.01). A large proportion (68%) of the individual growth rates derived from mark-recapture data were below those predicted by the otolith based von Bertalanffy growth model (p<0.01). This was attributed to the negative influence of external tags, as hydroids, frequently occurring on the tags of recaptured fish, were observed to cause severe lesions and in some cases, extensive fin damage. This brings into question the use of mark-recapture studies to calculate growth of some species. The effects of sampling design and sample size on age and growth estimation were assessed. The minimum sample size required to accurately estimate growth and mortality, and the effects of using either random or stratified sampling procedures were tested. Decimal and integer ageing both produced similar estimates of von Bertalanffy growth parameters, growth curves, spawner biomass-per-recruit (SB/R) and fishing mortality (F) estimates. Sampling monthly throughout the year and collecting data in a single large sample provided similar growth curves, von Bertalanffy, F and SB/R estimates. The data showed that estimates based on less than 300 random samples were unreliable. However, accurate growth parameter estimates were achievable with less than 200 samples if the sample was stratified with 10 or more samples per 2 cm size class. An investigation into the reproductive biology of A. argyrozona within the Tsitsikamma National Park revealed that they were serial spawning late gonochorists. The size at 50% maturity (L₅₀) was estimated at 292 and 297 mm FL for females and males, respectively. Both monthly gonadosomatic indices and macroscopically determined ovarian stages strongly suggest that A. argyrozona within the Tsitsikamma National Park spawn in the austral summer between November and April. The presence of post-ovulatory follicles (POF's) confirmed the six month spawning season, while monthly proportions of early (0-6 hour old) POF's showed that spawning frequency was highest (once every 1-2 days) from December to March. Although spawning season was more highly correlated to photoperiod (r = 0.859) than temperature (r = -0.161), the daily proportion of spawning fish was strongly correlated (r = 0.93) to ambient temperature over the range 9-22⁰C. Both spawning frequency and season increased with fish length. As a result of the allometric relationship between annual fecundity and fish mass a 3 kg fish was calculated to produce 5 fold more eggs per kilogram of body weight than a fish of 1 kg. In addition to producing more eggs per unit weight each year, larger fish also produce significantly larger eggs. Adult emigration and larval dispersal of A. argyrozona from the Tsitsikamma National Park (TNP), South Africa, were investigated using mark-recapture data and Acoustic Doppler Current Profiler measurements of currents. Tagging data showed that adult carpenter were mainly resident, with a small proportion (7%) leaving the TNP in both easterly and westerly directions. No relationship was found between fish movement patterns and fish size or time-at-liberty. Current patterns suggest that eggs and larvae spawned within the TNP are mainly transported eastwards towards established nursery grounds; the median estimated distance moved was 299 km (range 42-561 km) in 30 days (time to flexion). Given this pattern of ichthyoplankton dispersal together with the fact that adult carpenter within the TNP display a high degree of residency and that they are much more abundant than in adjacent fishing grounds (cpue = 23 times greater), it appears that the TNP protects a viable carpenter spawner population capable of seeding adjacent fishing grounds. Fishery independent biomass surveys and commercial linefish catch returns were used to elucidate the spatial patterns of A. argyrozona distributed along the South African continental shelf. Two distinct areas of abundance were determined, one on the central and the other on the eastern Agulhas Bank. Tagging studies revealed little exchange between them. Two distinct nursery areas were identified. These data suggest that in each area juvenile A. argyrozona settle and move inshore, and then move offshore as they grow. Otolith readability and growth rates varied between regions, with fish from the Eastern Cape having the lowest average percentage error and the slowest growth rates, readability decreased westward. L₅₀ varied between the central and eastern Agulhas Bank as did mass at length. Based on the distribution of carpenter, variability in otolith readability, mass at length, variation in growth and size at maturity, it is concluded that carpenter exist as two separate stocks, one on the central Agulhas Bank and the other on the eastern Agulhas Bank. SB/R, fecundity-per-recruit (Egg/R) and yield-per-recruit (Y/R) models were used to model both South African carpenter stocks. Owing to the allometric relationship between annual fecundity and individual size, Egg/R ratios were between 40 and 74% of SB/R at equivalent F. Egg/R ratios account for allometric increases in fecundity with size/age, and are therefore regarded as more accurate estimates of reproductive potential, and biological reference points for per-recruit analysis should wherever possible be based on this quantum. It is shown that the current length at first capture (lc) (250 mm TL) and F (at M = 0.1) will reduce Egg/R to 6.41% of the pristine value in the Eastern Cape and between 6.06 and 14.15% on the central Agulhas Bank, indicating that both stocks are heavily over exploited. An increase in lc from 250 to 350 mm TL and a 70% reduction in commercial fishing effort is recommended to attain a target reference point of 40% Egg/RF=0. Bag frequency analysis indicates that a reduction in daily bag limit from 10 to 4 fish.person¹.day⁻¹ would effect an equivalent reduction in recreational F. The trawl bycatch of carpenter is only 3% of the reported line catch, consequently restrictions to this fishery are not recommended.
- Full Text:
- Authors: Brouwer, Stephen Leonard
- Date: 2005
- Subjects: Reef fishes -- South Africa Sparidae -- South Africa
- Language: English
- Type: Thesis , Doctoral , PhD
- Identifier: vital:5241 , http://hdl.handle.net/10962/d1005084
- Description: Carpenter, Argyrozona argyrozona (Valenciennes, 1830), is an endemic South African sparid fish. They form an important component of the commercial linefishery on the South African east coast, where they are the third most important species landed. Recent investigations revealed that the catch per unit effort (cpue) of this species has declined markedly since the early 1900’s. Despite these declines and the importance of this resource, remarkably little biological information on this species exists for providing management advice. This thesis investigates the life history of carpenter, particularly those aspects that are used for management. This includes an investigation into the stock distribution and identification of nursery areas, and an assessment of age, growth, reproduction and movement patterns. Age and growth was assessed using methods based on both otoliths and mark-recapture. Transverse sagittal sections from the Tsitsikamma National Park showed clear opaque and translucent growth increments. Marginal growth zone analysis and mark-recapture of chemically tagged fish (Oxytetracycline) revealed that these were deposited on an annual basis: opaque in summer and translucent in winter. A. argyrozona were found to be long lived (up to 27 years) and slow growing. Within reader (between counts) and between readers average percent error (APE) was 5.3 and 1.8, respectively, showing that readability of carpenter otoliths is high. Comparison between whole and sectioned otoliths showed that the former significantly under-estimated the age of fish older than 10 years (p<0.01). A large proportion (68%) of the individual growth rates derived from mark-recapture data were below those predicted by the otolith based von Bertalanffy growth model (p<0.01). This was attributed to the negative influence of external tags, as hydroids, frequently occurring on the tags of recaptured fish, were observed to cause severe lesions and in some cases, extensive fin damage. This brings into question the use of mark-recapture studies to calculate growth of some species. The effects of sampling design and sample size on age and growth estimation were assessed. The minimum sample size required to accurately estimate growth and mortality, and the effects of using either random or stratified sampling procedures were tested. Decimal and integer ageing both produced similar estimates of von Bertalanffy growth parameters, growth curves, spawner biomass-per-recruit (SB/R) and fishing mortality (F) estimates. Sampling monthly throughout the year and collecting data in a single large sample provided similar growth curves, von Bertalanffy, F and SB/R estimates. The data showed that estimates based on less than 300 random samples were unreliable. However, accurate growth parameter estimates were achievable with less than 200 samples if the sample was stratified with 10 or more samples per 2 cm size class. An investigation into the reproductive biology of A. argyrozona within the Tsitsikamma National Park revealed that they were serial spawning late gonochorists. The size at 50% maturity (L₅₀) was estimated at 292 and 297 mm FL for females and males, respectively. Both monthly gonadosomatic indices and macroscopically determined ovarian stages strongly suggest that A. argyrozona within the Tsitsikamma National Park spawn in the austral summer between November and April. The presence of post-ovulatory follicles (POF's) confirmed the six month spawning season, while monthly proportions of early (0-6 hour old) POF's showed that spawning frequency was highest (once every 1-2 days) from December to March. Although spawning season was more highly correlated to photoperiod (r = 0.859) than temperature (r = -0.161), the daily proportion of spawning fish was strongly correlated (r = 0.93) to ambient temperature over the range 9-22⁰C. Both spawning frequency and season increased with fish length. As a result of the allometric relationship between annual fecundity and fish mass a 3 kg fish was calculated to produce 5 fold more eggs per kilogram of body weight than a fish of 1 kg. In addition to producing more eggs per unit weight each year, larger fish also produce significantly larger eggs. Adult emigration and larval dispersal of A. argyrozona from the Tsitsikamma National Park (TNP), South Africa, were investigated using mark-recapture data and Acoustic Doppler Current Profiler measurements of currents. Tagging data showed that adult carpenter were mainly resident, with a small proportion (7%) leaving the TNP in both easterly and westerly directions. No relationship was found between fish movement patterns and fish size or time-at-liberty. Current patterns suggest that eggs and larvae spawned within the TNP are mainly transported eastwards towards established nursery grounds; the median estimated distance moved was 299 km (range 42-561 km) in 30 days (time to flexion). Given this pattern of ichthyoplankton dispersal together with the fact that adult carpenter within the TNP display a high degree of residency and that they are much more abundant than in adjacent fishing grounds (cpue = 23 times greater), it appears that the TNP protects a viable carpenter spawner population capable of seeding adjacent fishing grounds. Fishery independent biomass surveys and commercial linefish catch returns were used to elucidate the spatial patterns of A. argyrozona distributed along the South African continental shelf. Two distinct areas of abundance were determined, one on the central and the other on the eastern Agulhas Bank. Tagging studies revealed little exchange between them. Two distinct nursery areas were identified. These data suggest that in each area juvenile A. argyrozona settle and move inshore, and then move offshore as they grow. Otolith readability and growth rates varied between regions, with fish from the Eastern Cape having the lowest average percentage error and the slowest growth rates, readability decreased westward. L₅₀ varied between the central and eastern Agulhas Bank as did mass at length. Based on the distribution of carpenter, variability in otolith readability, mass at length, variation in growth and size at maturity, it is concluded that carpenter exist as two separate stocks, one on the central Agulhas Bank and the other on the eastern Agulhas Bank. SB/R, fecundity-per-recruit (Egg/R) and yield-per-recruit (Y/R) models were used to model both South African carpenter stocks. Owing to the allometric relationship between annual fecundity and individual size, Egg/R ratios were between 40 and 74% of SB/R at equivalent F. Egg/R ratios account for allometric increases in fecundity with size/age, and are therefore regarded as more accurate estimates of reproductive potential, and biological reference points for per-recruit analysis should wherever possible be based on this quantum. It is shown that the current length at first capture (lc) (250 mm TL) and F (at M = 0.1) will reduce Egg/R to 6.41% of the pristine value in the Eastern Cape and between 6.06 and 14.15% on the central Agulhas Bank, indicating that both stocks are heavily over exploited. An increase in lc from 250 to 350 mm TL and a 70% reduction in commercial fishing effort is recommended to attain a target reference point of 40% Egg/RF=0. Bag frequency analysis indicates that a reduction in daily bag limit from 10 to 4 fish.person¹.day⁻¹ would effect an equivalent reduction in recreational F. The trawl bycatch of carpenter is only 3% of the reported line catch, consequently restrictions to this fishery are not recommended.
- Full Text:
Superstition, atheism and reasonable faith in Acts 26: a Graeco-Roman perspective on Paul’s defence before Festus and Agrippa
- Authors: Germiquet, Edouard Ariste
- Date: 2001
- Language: English
- Type: Thesis , Doctoral , PhD
- Identifier: vital:21065 , http://hdl.handle.net/10962/6224
- Description: This thesis investigates Luke‟s presentation of Paul‟s final and climactic defence of the gospel which takes place before Festus and King Agrippa II (Ac.26). It indicates how Luke has made use of the philosophical doctrine of the mean in order to present Christianity as a reasonable and rational faith. This investigation explores how Luke creates a literary framework within which to promote Paul as reasonable and rational through the application of the topos that true piety is the mean between the two extremes of superstition and atheism. The thesis is therefore structured around three dominant sections in which the major themes of superstition, atheism and rational faith are treated independently. Each section consists of an analysis of Luke‟s choice of words and his description of the behavioural patterns of each representative group so that a consistent picture progressively emerges in support of the basic framework. At all stages of the investigation, reference is made to contemporary moral philosophers, Hellenistic Judaism and the early Christian apologists so that the language, literary settings and stereotypes used by Luke can be clearly defined. This not only clarifies the text of Acts 26 but contributes to an overall appreciation of Luke‟s literary technique. At all points in the development of the thesis, the relevance and centrality which the resurrection has for Luke is kept in mind. This not only acts as a backdrop in understanding Luke‟s depiction of the superstitious and the atheist but is crucial in grasping Luke‟s presentation of Christianity as a rational faith. The thesis is brought to a close by a discussion on Luke's intended audience and the significance of his dedication to Theophilus.
- Full Text:
- Authors: Germiquet, Edouard Ariste
- Date: 2001
- Language: English
- Type: Thesis , Doctoral , PhD
- Identifier: vital:21065 , http://hdl.handle.net/10962/6224
- Description: This thesis investigates Luke‟s presentation of Paul‟s final and climactic defence of the gospel which takes place before Festus and King Agrippa II (Ac.26). It indicates how Luke has made use of the philosophical doctrine of the mean in order to present Christianity as a reasonable and rational faith. This investigation explores how Luke creates a literary framework within which to promote Paul as reasonable and rational through the application of the topos that true piety is the mean between the two extremes of superstition and atheism. The thesis is therefore structured around three dominant sections in which the major themes of superstition, atheism and rational faith are treated independently. Each section consists of an analysis of Luke‟s choice of words and his description of the behavioural patterns of each representative group so that a consistent picture progressively emerges in support of the basic framework. At all stages of the investigation, reference is made to contemporary moral philosophers, Hellenistic Judaism and the early Christian apologists so that the language, literary settings and stereotypes used by Luke can be clearly defined. This not only clarifies the text of Acts 26 but contributes to an overall appreciation of Luke‟s literary technique. At all points in the development of the thesis, the relevance and centrality which the resurrection has for Luke is kept in mind. This not only acts as a backdrop in understanding Luke‟s depiction of the superstitious and the atheist but is crucial in grasping Luke‟s presentation of Christianity as a rational faith. The thesis is brought to a close by a discussion on Luke's intended audience and the significance of his dedication to Theophilus.
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A phenomenological investigation into the psychoanalytic psychotherapist's experience of identifying, differentiating and processing the patient's transference-based and reality-oriented reactions
- Authors: Danilewitz, Larry Mark
- Date: 1993
- Subjects: Reality therapy Transference (Psychology) -- Therapeutic use
- Language: English
- Type: Thesis , Doctoral , PhD
- Identifier: vital:2960 , http://hdl.handle.net/10962/d1002469
- Description: The aim of this study was to describe the psychoanalytically-oriented therapist's experience of identifying, differentiating and processing the patient's transference-based and reality-oriented reactions. In order to investigate the therapist's lived experience of being receptive to the total communication of the patient in the analytic situation, the researcher adopted the empirical phenomenological method. This descriptive and intuitive method grounded the researcher in the concreteness of the everyday life-world of the therapist, and enabled him to explicate the therapist's immediate, pre-theoretical experiences of his patient. The appropriate central research question, formulated to elicit the experience of this phenomenon, emerged through the process of enquiry during the pilot study. Thirteen experienced, psychoanalytically-oriented psychotherapists were interviewed and the five protocols considered most revelatory of the phenomenon under investigation were analyzed in detail. The remaining eight protocols were used to illuminate central themes and to clarify areas of uncertainty during the phase of formal explication. The central findings revealed that the oscillating process of the therapist as he shifts from being immersed in the world of his patient to being in a position of observation and self reflection is the fulcrum around which he evaluates the nature of his patient's communications. During this ongoing process of discrimination, living in duality, the therapist comes to experience himself as a patient scrutinized by his own and his patient's confrontations. His journey of disentanglement, the endeavour to differentiate his responses from his patient's actions, is dependent on his ability to engage in honest selfreflection and to access his pre-theoretical and articulated cognitions of his patient. This allows him to acknowledge his own role in what has unfolded interpersonally and to appropriate his previously denied feelings for and attitudes towards his patient, a prerequisite for the accurate and full appraisal of the nature of his patient's communications. Forsaking fixed judgements, the therapist becomes open to the confluence between the reality-oriented responses and transference-based reactions of his patient. This salient discovery, when dialogued with the literature, reinforced the theories of Greenson and Langs that not all the interactions between the patient and the analyst/therapist are transference-based and that it is therefore imperative that the analyst/therapist reflect on his participation in the analytic situation.
- Full Text:
- Authors: Danilewitz, Larry Mark
- Date: 1993
- Subjects: Reality therapy Transference (Psychology) -- Therapeutic use
- Language: English
- Type: Thesis , Doctoral , PhD
- Identifier: vital:2960 , http://hdl.handle.net/10962/d1002469
- Description: The aim of this study was to describe the psychoanalytically-oriented therapist's experience of identifying, differentiating and processing the patient's transference-based and reality-oriented reactions. In order to investigate the therapist's lived experience of being receptive to the total communication of the patient in the analytic situation, the researcher adopted the empirical phenomenological method. This descriptive and intuitive method grounded the researcher in the concreteness of the everyday life-world of the therapist, and enabled him to explicate the therapist's immediate, pre-theoretical experiences of his patient. The appropriate central research question, formulated to elicit the experience of this phenomenon, emerged through the process of enquiry during the pilot study. Thirteen experienced, psychoanalytically-oriented psychotherapists were interviewed and the five protocols considered most revelatory of the phenomenon under investigation were analyzed in detail. The remaining eight protocols were used to illuminate central themes and to clarify areas of uncertainty during the phase of formal explication. The central findings revealed that the oscillating process of the therapist as he shifts from being immersed in the world of his patient to being in a position of observation and self reflection is the fulcrum around which he evaluates the nature of his patient's communications. During this ongoing process of discrimination, living in duality, the therapist comes to experience himself as a patient scrutinized by his own and his patient's confrontations. His journey of disentanglement, the endeavour to differentiate his responses from his patient's actions, is dependent on his ability to engage in honest selfreflection and to access his pre-theoretical and articulated cognitions of his patient. This allows him to acknowledge his own role in what has unfolded interpersonally and to appropriate his previously denied feelings for and attitudes towards his patient, a prerequisite for the accurate and full appraisal of the nature of his patient's communications. Forsaking fixed judgements, the therapist becomes open to the confluence between the reality-oriented responses and transference-based reactions of his patient. This salient discovery, when dialogued with the literature, reinforced the theories of Greenson and Langs that not all the interactions between the patient and the analyst/therapist are transference-based and that it is therefore imperative that the analyst/therapist reflect on his participation in the analytic situation.
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The biology of the South African cliff swallow hirundo spilodera
- Authors: Earlé, Roy Anthony
- Date: 1986
- Subjects: Hirundo pyrrhonota Birds -- Breeding -- South Africa Birds -- Behavior -- South Africa
- Language: English
- Type: Thesis , Doctoral , PhD
- Identifier: vital:5631 , http://hdl.handle.net/10962/d1004927
- Description: The general biology of the South African Cliff Swallow Hirundo spilodera was studied over a two year period in the central Orange Free State. This species is highly colonial, nesting mostly on man-made structures such as concrete road bridges. Adult birds were usually faithful to their breeding colony and very few individuals changed colonies. The Cliff Swallow had a surprisingly large vocal repertoire for a swallow and contact calls of the young were individually recognizable. Three species-specific ectoparasites parasitized the Cliff Swallow but none seemed to have a noticeable negative effect on the swallows. Breeding started earlier in larger colonies than in smaller ones and conspecific brood parasitism was a common feature in some colonies. Individual pairs made up to four breeding attempts per season. The findings of this study are compared with the available information on other members of the Hirundinidae and the advantages and costs of Cliff Swallow coloniality are discussed.
- Full Text:
- Authors: Earlé, Roy Anthony
- Date: 1986
- Subjects: Hirundo pyrrhonota Birds -- Breeding -- South Africa Birds -- Behavior -- South Africa
- Language: English
- Type: Thesis , Doctoral , PhD
- Identifier: vital:5631 , http://hdl.handle.net/10962/d1004927
- Description: The general biology of the South African Cliff Swallow Hirundo spilodera was studied over a two year period in the central Orange Free State. This species is highly colonial, nesting mostly on man-made structures such as concrete road bridges. Adult birds were usually faithful to their breeding colony and very few individuals changed colonies. The Cliff Swallow had a surprisingly large vocal repertoire for a swallow and contact calls of the young were individually recognizable. Three species-specific ectoparasites parasitized the Cliff Swallow but none seemed to have a noticeable negative effect on the swallows. Breeding started earlier in larger colonies than in smaller ones and conspecific brood parasitism was a common feature in some colonies. Individual pairs made up to four breeding attempts per season. The findings of this study are compared with the available information on other members of the Hirundinidae and the advantages and costs of Cliff Swallow coloniality are discussed.
- Full Text:
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