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An evaluation of wind energy potential for power generation in Mozambique.Zucule, Jonas Nombora. January 2012 (has links)
Wind energy is a continuous, clean source of energy that can be harnessed for electricity
generation or water pumping. The geographic location of Mozambique, and the long
coastline renders the country a good wind energy potential that could potentially be
exploited for water pumping or electrical power systems that have social and economic
benefits and thereby contribute to a reduction in unsustainable practices of wood
biomass burning which is the main source of energy in rural villages and high density
suburbs of the main cities of the country.
This study is focused on evaluating the potential of harnessing wind energy for
electrical power generation in Mozambique using the Wind Atlas Analysis and
Application Programme (WAsP) model. The study characterises wind speed patterns
and wind frequency distributions at selected meteorological stations based on hourly
observations, and models the available wind energy in coastal and interior areas.
Meteorological parameters such as wind speed data from nearby meteorological stations
and wind turbine characteristics were used as inputs into the model. To effectively
harness wind energy, mean annual wind speeds should at least be 3 ms-1. For this reason
only sites satisfying this criterion were selected. The spatial selection criteria considered
a fair distribution of candidate sites such that coastal areas of the southern, northern and
the interior Niassa and Nampula provinces were covered.
The results of the WAsP model simulations, indicate that there is sufficient wind energy
resource in both interior and coastal areas, which varies with height a.g.l., and that can
be exploited for pumping water and generating electricity in small or medium electrical
power systems, particularly the coastal areas of Ponta de Ouro, Mavelane, and Tofinho
where the mean annual wind speed is above 5.0 ms-1 at the 10 m level and about
8.0 ms-1 at the highest levels (50 - 60 m a.g.l.) and interior area of Lichinga (mean
annual wind speed of about 6 ms-1 at the same highest levels). The lowest wind energy
potential (mean annual wind speed of about 4.0 ms-1) is found in the Nampula area. / Thesis (M.Sc.)-University of KwaZulu-Natal, Westville, 2012.
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Influence of Trichinelle zimbabwensis infection intensity on predilection sites, blood biochemical values and humoral immune response in experimentally infected Nile crocodiles (Crocodylus niloticus)La Grange, Louis Jacobus. 01 November 2013 (has links)
The zoonotic potential of Trichinella zimbabwensis as supported by the clinical symptoms observed in experimentally infected, non-human primates (Mukaratirwa et al., 2001) necessitates research aimed at elucidating the distribution and epidemiology of this parasite. No controlled studies have been conducted to determine the predilection muscles of Trichinella zimbabwensis larvae in Nile crocodiles (Crocodylus niloticus) or the influence of infection intensity on the distribution of the larvae in crocodiles. Neither has the influence of Trichinella zimbabwensis on biochemical parameters in crocodiles been assessed previously. To determine the distribution patterns of Trichinella zimbabwensis larvae and predilection muscles and to assess the influence on selected biochemical parameters, fifteen crocodiles were randomly divided into three cohorts of five animals each to represent high infection (642 larvae/kg of body weight), medium infection (414 larvae/kg of bodyweight) and low infection (134 larvae/kg of bodyweight) cohorts. In the high infection cohort, high percentages of larvae were observed in the tricep muscles (26%) and hind limb muscles (13%). In the medium infection cohort, high percentages of larvae were found in the tricep muscles (50%), sternomastoid (18%) and hind limb muscles (13%). For the low infection cohort, larvae were mainly found in the intercostal muscles (36%), longissimus complex (27%), forelimb muscles (20%), and hind limb muscles (10%). Predilection muscles in the high and medium infection cohorts were similar to those reported in naturally infected crocodiles despite changes in infection intensity. The high infection cohort had significantly higher numbers of larvae in the intercostal, longissimus complex, external tibial flexor, longissimus caudalis and caudal femoral muscles (P < 0.05) compared to the medium infection cohort. In comparison to the low infection cohort, the high infection cohort harboured significantly higher numbers of larvae in all muscles (P < 0.05) except for the tongue and pterygoid. The high infection cohort harboured significantly higher numbers of larvae (P < 0.05) in the sternomastoid, tricep, intercostal, longissimus complex, external tibial flexor, longissimus caudalis and caudal femoral muscles compared to naturally infected crocodiles. The importance of host characteristics in determining predilection and the importance of leg musculature as a predilection site for Trichinella spp. in sylvatic carnivores were both confirmed in this study.
Deviations from normal parameters of blood glucose, alanine transaminase (ALT), aspartate transaminase (AST), creatine phosphokinase (CPK) and lactate dehydrogenase (LDH) compared to observations in uninfected reptiles were observed.
Hypoglycaemia was not observed in the infected groups in this study. The humoral immune response to Trichinella zimbabwensis infection was evaluated in all three groups by way of indirect ELISA. Peak values of blood glucose, LDH and AST were observed on day 56, 49 and 42 p.i. in the high, medium and low infection cohorts respectively. CPK values peaked on day 35 p.i. in all three cohorts. Peak ALT values were reached on day 56 in the high infection cohort and on day 28 p.i. in both the medium and low infection cohorts. No correlations between the biochemical parameters and infection intensity were observed. Peak antibody titres were reached on day 49 p.i. in the medium infection cohort and on day 42 p.i. in both the high and low infection cohorts. Infection intensity could not be correlated with the magnitude of the humoral immune response or time to seroconversion. The effect of infection intensity on time to seroconversion, magnitude and persistence of the humoral immune response was assessed. No significant differences in the titre levels between the three groups were observed. Infection intensity could not be correlated with the magnitude of the humoral response or time to seroconversion. Results of this study were in agreement with results reported in mammals (wild boars and horses) infected with other Trichinella species and showed that antibody titres could not be detected indefinitely. / Thesis (M.Sc.)-University of KwaZulu-Natal, Westville, 2013.
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An investigation of solid waste management practices : the case of the Chatsworth township in metropolitan Durban - KwaZulu-Natal.Dawnarain, Reena B. January 2004 (has links)
Solid waste management is a global phenomenon that presents one of the most
immediate and serious challenges in developing urban areas. Chatsworth is a formal
residential township and is a product of the apartheid system, where solid waste
removal was not seen as a priority. The inefficient waste management system has
resulted in environmental degradation with solid waste increasingly being disposed
off in streets, open spaces and streams etc. Waste heaps are becoming the breeding
places of insects and pests and potential health hazards. Moreover, the aesthetics of
this formal residential area is lost due to bad odour, unsightly dumpsites and
deterioration of the environment.
With most residential areas in South Africa having formal waste removal services, the
continued existence of illegal dumps is still a serious problem . In the light of the
above, the aim of this study was to investigate the solid waste management practice in
Chatsworth and its negative impact on the human and natural environments. The
social dimensions, perceptions, attitudes and solid waste practices of households were
investigated to examine the relationship between socio-economic status and current
waste practices. A survey assessment was conducted by means of a questionnaire
designed to get community opinions and understanding of the type of service they
received from the municipality. One hundred questionnaires were administered to
householders in the study area. The study was complemented with semi-structured
interviews with specific people of interest. The Statistical Package for Social
Scientists was used for data entry and analysis.
The findings of this study indicated that the waste collection system is inefficient and
the attitudes, perceptions and socio-economic characteristics are significant factors contributing to effective waste management practices. Appropriate policy backed by
legislation and enforceable regulations must underpin the strategic alternatives
selected to deal with waste management in the eThekwini Municipality. The planning
of integrated waste management should be seen as part of the solution of waste
management and waste management should be appreciated as a public service that
provides employment. resource recovery, and safe disposal of hazardous waste,
reduced pollution and community development projects. / Thesis (M.A.)-University of KwaZulu-Natal, 2004.
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Females' environmental perceptions of violence and danger in secondary schools : case studies from the Durban Metropolitan area.Perry, Edwin C. January 2002 (has links)
There has been a significant level of outcry opposing violence against females and the
development of policies and legislation aimed at reducing this increasing problem that
confronts South African society. Yet, violence and the fear of violence, especially
gender-based violence, are widespread in South Africa. Despite the considerable
research that has been undertaken on violence in South Africa, there remains a weak
empirical and conceptual basis to understand females' environmental perceptions of
violence and danger in secondary schools. This dissertation contributes to a greater
understanding of the relationships between gender, violence and environmental
perceptions. Gender specific spatialities, experiences and perceptions are critically
examined. Critical concerns in the study include females' environmental perceptions
of violence and images of danger in secondary schools, sources of information
regarding violence and danger, types of violence that females are aware of, specific
experiences of violence among the respondents and the coping strategies adopted by
females.
To enable a critical examination of the above issues, a comprehensive literature
review was undertaken as well as fieldwork was conducted in two secondary schools
(Dr A D Lazarus and Ridge Park College). Both female learners and teachers
participated in the study. A variety of quantitative and qualitative methods were used
including questionnaire surveys as well as mental mapping and ranking exercises to
achieve the aims and objectives of this study.
The key findings of the research show that violence and the danger of violence
constrain the movements and the options of females. Furthermore, the results clearly
illustrate discernible patterns of fear of violence, experiences of violence, perceptions
of violence and responses to the perceived threat of violence among the respondents.
Additionally, a disconcerting finding was that a significant proportion of the
respondents at both schools viewed the school itself to be unsafe or located in close
proximity to areas that they perceived to be dangerous.
Undoubtedly, addressing issues pertaining to gender and violence in secondary
schools (and in society more generally) will enhance females' abilities to effectively
participate in and benefit from educational and development processes. This study
shows that acts of violence generally and gender-based violence particularly need to
be understood in their environmental contexts inclusive of the location! spatial, social,
economic and political dimensions. Moreover, perceptions and the fear of violence,
although they may not match actual risk, need to be responded to constructively. / Thesis (M.A.)- University of Durban Westville, 2002.
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Use of constructivism in the development and evaluation of an educational game environment.Seagram, Robert. January 2004 (has links)
Formal learning contexts often present information to learners in an inert and highly abstract form, making it
unlikely that learners would ever use this information in their every-da y lives. Learners do, however, show a
greater propensity for retaining information that is seen as having relevance in their lives . Constructivism is an
educational paradigm that has gained popularity amongst educationists. The core tenet of this paradigm is that
learners learn through interaction with their environment and that all knowledge construction is based on
previous life experience. Information that is presented to learners in a contextualised form not only has a better
chance of being retained in long-term memory, but also has a greater likelihood of being applied in relevant life
situations. This publication deals with the research, design and delivery of important information concerning
diseases that have a major impact in Southern Africa. Firstly, learners at the University of Natal, Durban were
polled for their existing knowledge concerning four widespread diseases, namely HIV/AIDS , tuberculosis,
malaria and cancer. Aspects of these diseases where learners demonstrated a low level of awareness were
defined as the primary learning object ives for an educational 3D- immersive microworld. Areas of knowledge
concerning the transmission, symptomatic expression, biology and prevention of these diseases were generally
not well represented in the learner sample. Hence, information regarding these aspects is presented to learners in
a contextualised form within the microworld. Motivation for learners to play in this microworld is provided by a
storyline that was researched and written for the portal. In addition, the model used in the storyline design was
evaluated for its effectiveness as a tool to be used in the planning of future educational games. A model, the
Puzzle Process model, was proposed to inform the design of puzzle interfaces for these types of interactive
learning environments, and puzzle interfaces were designed for the virtual environment according to the model
guidelines. The learning environment was tested as part of the formative evaluation with a small sample of
learners . The testing process made use of both quantitative and qualitative methodologies to evaluate the
effectiveness of the learning environment as a possible learning tool. Comparison of pre- and post-gameplay
questionnaires showed that learners gained a more indepth and richer understanding of the topics being dealt
with in the portal. In particular, the puzzle objects situated in the environment stimulated learners to negotiate
meanings for the puzzle interfaces and, in the process, encouraged learners to discuss the topic being dealt with.
Results from this study also show that the longer learners discussed and negotiated a certain knowledge domain,
the greater their increase in richness of information was for that knowledge domain after gameplay. These
results highlight the importance of social dialogue in the knowledge construction process and suggest that
environments like these have great potential based on their ability to encourage learners to talk to one another
and their facilitators while negotiating mutually acceptable knowledge. The original Puzzle Process model, as
well as the Game Achievement model and the Game Object model were modified to account for the need for
social dialogue and content. These more comprehensive models are instrumental for use in future virtual world
environment design. / Thesis (Ph.D.)-University of KwaZulu- Natal, Durban, 2004
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Evaluation of spoor tracking to monitor cheetah abundance in central northern Namibia.January 2007 (has links)
The design, implementation, management and the evaluation of sound conservation practices, is often dependent on the availability of reliable estimates of animal abundance. Large carnivores often pose particular problems in this regard, due to their low densities and wide-ranging behaviour, so the true abundance of such species are seldom able to be reported in literature . As a result, the use of indices of abundance, mostly for relative abundance, has been investigated. However, before these indices can be reliably utilized for conservation purposes , there is a pressing need to calibrate them. As of yet, calibration studies have primarily been performed on demarcated conservation areas, where individuals could be individually identified. Not all these calibrations studies reported indices to be a function of true density. Nevertheless , spoor frequency has been reported to be a function of true density for carnivores in certain Parks in Namibia . Precisely , cheetah spoor density was reported to correlate with visuals in the Kgalagadi Transfrontier Park. The majority of these studies elucidate a species spatial organization, animal behaviour, as the paramount factor determining the relationship between densities estimated via different censusing methods. Thus, the efficiency of spoor frequency to estimate and monitor relative abundance for wild cheetahs is yet to be empirically tested . Despite the lack of a true density estimate for the free-ranging cheetahs in the study area, evaluated spoor tracking as a possible index to monitor relative cheetah abundance using radiotelemetry densities estimates as representative of true abundance for the area, for the 1995 to 2000 period. The study is considered to be opportunistic , and a pillar for future research, as transects where spoor tracking was conducted were layout primarily for ungulates strip counts. Least-linear regression and Spearman's correlation were used to evaluate the relationship between density estimates derived by the two methods. Percentages of change on annual densities were also regressed as a mean to test spoor frequency sensitivity to density changes. The calibration of spoor frequency with estimates of density produced using radio-telemetry, without the ascription of imprints to individual animals, was poor (rs=17.4, y=0.36+0.20). The sensitivity analysis also showed spoor tracking poor reliability to monitor cheetah population. This can be attributed, in order of importance, to the discrepancies on the spatial extent sampled by the two methods, the species large home ranges, substrate quality , habitat preferences, the availability of farm road networks and the transect design, i.e., cyclic. However, the paramount factor limiting the study conclusions was the lack of a more local density estimate at a farm level. Therefore, the use of spoor frequency to estimate wild cheetah relative abundance requires further research, particularly using a different sampling design, longer straight transects and the acquisition of local densities estimates. / Thesis (M.Sc.)-University of KwaZulu-Natal, Pietermaritzburg, 2007.
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A survey to assess perceptions on the value of examining survey records within the Surveyor-General(s) Office(s).Rowe, Oliver allan. January 2011 (has links)
The examination of survey diagrams and records submitted by Professional Land Surveyor(s), has been the responsibility of the Surveyor-General(s) Office(s) in South Africa since the passing of the Land Survey Act 9 of 1927 and its successor, the Land Survey Act 8 of 1997. As it stands Professional Land Surveyor(s), registered with the South African Institute of Professional and Technical Surveyors, are the only persons authorised to place and replace cadastral boundaries. Together with the Surveyor-General(s) Office(s), they ensure the integrity of our land tenure system. This research investigated the perceptions of the Professional Land Surveyor(s) and the examiners, as to whether this examination process is necessary to ensure the integrity of the land tenure system, or whether it is a mere hindrance to the registration of land within the Deeds Office(s). A qualitative research approach was undertaken whereby a questionnaire was developed and distributed to all registered Professional Land Surveyor(s) operating in KwaZulu-Natal. In addition, semi-structured interviews were performed at the offices of the Surveyor-General with the staff involved with the examination process. It was established that the examination, although perceived as a delay in the registration of property, is vital and if compromised there is a distinct risk of losing the security and integrity that presently exist within the cadastral system. It would appear that the integrity of our cadastral system is not found solely in the professional land surveyor or the examination section, but rather that the combined efforts of the two parties provides an end product that is accurate, correct and ensures that the integrity of the cadastre system is maintained. / Thesis (M.Sc.)-University of KwaZulu-Natal, Pietermaritzburg, 2011.
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An assessment of local government capacity in KwaZulu-Natal to implement the National Environmental Management : Air Quality Act.Naiker, Yegeshni. January 2007 (has links)
The radical shift in approach to the Air Quality Management (AQM) strategy that has been introduced
recently, through the promulgation of the National Environmental Management: Air Quality Act (AQA),
makes provision for a number of innovative measures in the control of air pollution in South Africa. These
include the appointment of Air Quality Officers, the development of Air Quality Management Plans, the
designation of priority areas, the provision for stricter enforcement conditions, and the broad
implementation of monitoring. A significant change is in the form of delegating the greatest responsibility
for implementation of measures to the local government tier, comprised of metropolitan areas, district and
local municipalities. Local authorities are recognised as a sphere of government, however, they are
impeded, inter alia, by matters of limited financial resources, lack of skills capacity, and the slow
transformation of organisational culture and structure (Cloete, 2002).
The implementation ofthe AQA by local government is framed by an understanding ofthe responsibilities
of local government, as well as the principal components of AQM and their implementation. The selected
areas for study are Uthungulu, Uthukela, and Ugu district municipalities in KwaZulu-Natal, representing
administrative and geographical variation. Existing and potential air quality issues, and their plans to
address these issues, were identified and assessed in the municipalities using the Integrated Development
Plans. The capacity of municipalities to implement the AQA was assessed using interviews, focusing on
the interpretation of the AQA, technical capabilities, and implementation of AQM. Awareness of
municipal responsibilities under the AQA was limited, although advances in AQM implementation had
been made by municipalities. Responsibilities reflecting technical measures or activities that were
currently undertaken by the municipality, such as monitoring and enforcement, were well recognised.
However, the related policy and management tools, of Air Quality Officer (AQO) appointment and Air
Quality Management Plan (AQMP) development, were less emphasised by municipal respondents.
Limited progress in implementation of the AQA was observed, with only AQO appointment and ambient
monitoring being significantly applied.
The greatest challenge facing municipalities is the securing of financial resources for personnel and
equipment. Progress in technical fundamentals is noted, most notably in emission inventories and
monitoring capabilities, although communication on air quality issues remains poor, with limited
mechanisms in place for inter-governmental or public communication. There is a prevalence of the use of
AQMPs as planning tools, as well as general concepts of town planning and zoning. However, in general,
planning departments are not involved. A significant proportion of municipalities have a means of
assessing progress, whether explicitly or not. A framework for implementing the AQA is produced to
guide local government efforts, and provides a summation of the outcomes of the research. / Thesis (M.Sc.)-University of KwaZulu-Natal, 2007.
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Organizational culture and its underlying basic assumptions as a determinant of response to change : a case study of KwaZulu-Natal's conservation sector, South Africa.Nyambe, Nyambe. January 2005 (has links)
This study was concerned with elaborating theory and informing practice about the process of managing change in organizations. It was premised on the implications of organizational culture and its underlying basic assumptions for strategy, particularly in terms of responsiveness and resistance to change. Harmony between the external environment and an organization's culture was postulated as a critical determinant of the rate of uptake and acceptance of new strategic directions in an organization. Drawing from organizational and critical social theories, past conservation efforts in KwaZulu-Natal were reinterpreted in the light of historical and contemporary developments. The theoretical contribution rests on exploring how basic assumptions, as the core of a culture, may be conceptualized and accessed to examine historically and culturally based meanings of conservation. The practical contribution relates to the need for mechanisms to explicitly address basic assumptions as the core of an organizational culture. Data collection and analysis were informed by the ideas of hermeneutic philosophy, Giddens' Theory of Structuration and Schein's framework of organizational culture. The main source of primary data was interviews that were tape-recorded, transcribed and analysed using a multi-stage process in data organization and interpretation. The analysis involved the identification of common themes and differences in opinion amongst the respondents. Data analysis was done with the help of Nvivo - computer software for qualitative research. The software did not effect the analysis, but assisted in organizing the interview transcripts for analysis purposes: facilitating easy storage, retrieval and querying. The findings revealed a temporal variance in the understanding and interpretation of the mission of conservation in KwaZulu-Natal. Respective executive leaders of the two erstwhile conservation agencies in KwaZulu-Natal were historically very influential in shaping the mission. For the present leadership, four basic assumptions emerged from the data: 'public funding defines who we are'; 'we are leaders in conservation'; 'we know our realities are changing' and 'we are conserving a great natural and cultural heritage'. These assumptions reflect the various themes which the respondents discussed in respect of the present-day strategy processes in conservation in KwaZulu-Natal. Within and across these four assumptions, respondents expressed variable and sometimes contradictory meanings and interpretations. Differences were especially noticeable between the conservation sector's historical inclinations towards public service and its emergent commercial activities. Overall, the study demonstrated the variety of perspectives the respondents used to interpret their understanding and meanings of what the fundamental mission of conservation in KwaZulu-Natal ought to be. The findings highlight the need for those involved in strategic processes to base their activities, and their approaches to managing change, on the continual exploration of basic assumptions as the portal for the ideas, perceptions and beliefs that influence change. In matters of strategy, leaders should work with the prevailing organizational culture and its underlying basic assumptions, rather than develop the strategy and then attempt to deal with the basic assumptions and cultural support afterwards. Finally, the findings suggest that in all visioning and strategy development processes, whether in a conservation agency or some other organization, explicit analysis of assumptions is critical for securing support for, and reducing prospects of resistance to change. Among members of an organization, visions, missions and strategies are unlikely to be effectively internalized unless they accord with the assumptions they hold. This process requires explicit mechanisms for doing so, and this study highlights such mechanisms. / Thesis (Ph.D.)-University of KwaZulu-Natal, Pietermaritzburg, 2005.
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A viable strategy to sugar cane lignocellulosic bio-ethanol development in Southern Africa.Qwabe, Sabatha Thulane. January 2004 (has links)
In the current era, oil deficit countries around the world seriously consider shifting dependence from conventional gasoline to renewable bio-ethanol fuel in the
transport industry. Arguably, blending l0vol% dry ethanol with 90vol% unleaded gasoline enables ethanol fuel to penetrate the fuel market at relatively lower development costs. Despite creating an important market for the ethanol industry, fuels containing dry ethanol of differential proportions multiply the local risks associated with fuel combustion. Making a sale of one drop of ethanol fuel, for example, is intrinsically tied to the sale of more drops of imported gasoline. Furthermore, an increase (decrease) in conventional fuel prices directly influences a decline (increase) in daily sales of ethanol fuel. Blending bio-ethanol fuel with
conventional gasoline in various proportions fails to address the multifaceted fossil fuel crisis in oil deficit countries. Although reducing bio-ethanol production costs can buffer fuel prices to a significant degree when blended in higher ratios, industrial competition for bio-feedstock is a serious limitation for bio-ethanol development in all parts of the globe. Nevertheless, advances in biotechnology may allow the use of a wide range of cheaper ethanol feedstocks (e.g. lignocellulose) leading to an important reduction in ethanol production costs. Temporal and spatial variability of lignocellulosic ethanol potentials in the sugar industry is investigated over southern Africa as a whole. The influence of extremely low (high) production of sugar cane on the potentials development of
lignocellulosic ethanol plants is demonstrated in this work. Characterization of bioethanol fuel markets on the basis of blending with gasoline is undertaken at the subcontinental scale. The connectivity between development, consumption per capita, population growth, bio-ethanol energy demand, as well as the critical limits of land stock potentials is examined in this study. On the basis of the special influence that each of the processes indicated above have on bio-ethanol fuel development, an
integrated approach toward optimizing the total value of bio-ethanol fuel in the region is formulated. This approach allows the investigation to determine whether critical and beyond critical conditions of land stock lead to a collapse of a human consumption type or whether bio-ethanol fuel development is a totally viable process. Finally, this work ascertains whether sustainable biofuel development is an oxymoron because human development demands a constantly growing fuel consumption per capita, or because of increasing the lower limit, with an infinite upper limit for human development, or as a product of the combined effects of increasing human population with a higher consumption rate per capita of non-growing and non-developing land stock units. / Thesis (Ph.D.)-University of KwaZulu Natal, Durban, 2004.
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