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Livro de resumos - II International Conference on Sport in Africa

II International Conference on Sport in Africa
Fonte: CEA-IUL Publicador: CEA-IUL
Tipo: Conferência ou Objeto de Conferência
Publicado em /06/2012 POR
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46.4%
The Center of African Studies of the ISCTE-Lisbon University Institute, in cooperation with the Institute of Social Sciences of the University of Lisbon, the Sport: Laboratory of the History of Sport and Leisure, of the Federal University of Rio de Janeiro and the Group of African Studies of the Fluminense Federal University, are promoting the II International Conference on Sport in Africa, entitled Sport and leisure in Africa: practices and identities, in Lisbon on the 5 and 6 of June 2012.

Brazil in Africa: Ambitions and Achievements of an Emerging Regional Power in the Political and Economic Sector

Seibert, Gerhard
Fonte: The Nordic Africa Institute Publicador: The Nordic Africa Institute
Tipo: Conferência ou Objeto de Conferência
Publicado em //2011 ENG
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Thanks to Brazil’s geographic and demographic size and steady economic growth in recent years, the country has succeeded in consolidating its position as an emerging middle power in the international political system. The strengthening of south-south cooperation in general and the renewal of relations with Africa in particular are integral parts of Brazil’s political ambitions in a new global context. President Lula da Silva’s (2003-2010) many visits to African countries and the significant increase in the number of Brazilian embassies in Africa reflect the importance of the continent as part of Brazil’s new global foreign policies. The considerable growth in trade with African countries over the last decade is another proof of increasing Brazilian interest in Africa. This paper examines the development of relations between Brazil and Africa at political and diplomatic, commercial and development cooperation level in the last decade.

The Global Game has changed: What Role for Europe-Africa Relations?

Europe Africa Research Network
Fonte: Instituto Universitário de Lisboa Publicador: Instituto Universitário de Lisboa
Tipo: Livro
Publicado em 30/04/2014 ENG
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This publication approaches some of the issues involved in the reshaping of EU-Africa relations in the recent past and for the next few years. Several authors, from Europe and from Africa, assess the partnership’s achievements so far and also the upcoming challenges in accommodating diverging interests and effectively responding to global challenges, so as to generate the famous win-win outcomes all partners are looking for.

The Bushmanland Group supracrustal succession, Aggeneys, Bushmanland, South Africa: Provenance, age of deposition and metamorphism

Bailie, Russell; Armstrong, Richard; Reid, David
Fonte: Geological Society of South Africa Publicador: Geological Society of South Africa
Tipo: Artigo de Revista Científica
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The central portion of the structurally complex and poly-metamorphosed Namaqua Province of western South Africa is underlain by a series of pelitic and psammitic metasediments, termed the Bushmanland Group, which is host to world class Broken Hill-type Pb

Composition and single zircon U-Pb emplacement and metamorphic ages of the Aggeneys Granite Suite, Bushmanland, South Africa

Bailie, Russell; Armstrong, Richard; Reid, David
Fonte: Geological Society of South Africa Publicador: Geological Society of South Africa
Tipo: Artigo de Revista Científica
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The central Bushmanland portion of the Namaqua Province of South Africa is underlain by three voluminous suites of granitic gneisses, termed the Achab, Hoogoor and Aroams Gneisses, in the Aggeneys District, the site of major world-class Broken Hill-type P

The Kaapvaal Craton and adjacent orogens, southern Africa: a geochronological database and overview of the geological development of the craton

Eglington, B.M.; Armstrong, Richard
Fonte: Geological Society of South Africa Publicador: Geological Society of South Africa
Tipo: Artigo de Revista Científica
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Geochronological comparisons of large datasets are facilitated by the use of structured databases. Data for the Precambrian of South Africa, Swaziland, Lesotho and Botswana have been compiled in a DateView database and linked to chronostratigraphy and GIS databases to produce a series of 'time-slice' maps illustrating the development of the Kaapvaal Craton. Linking geochronological data to GIS coverages provides a valuable visual perspective on the development of the southern African lithosphere. The oldest preserved rock formation dates occur south of the Barberton Greenstone Belt in South Africa and Swaziland. Subsequent scattered development of new crust occurred in the south eastern, eastern and northern Kaapvaal Craton before being 'stitched' together by extensive granitoid intrusions at ∼3.25 Ga and ∼3.1 Ga. Coeval development of new crust occurred in what would later become the central zone of the Limpopo Belt. The patterns of igneous activity from ∼3.1 Ga to ∼2.8 Ga, outboard of major cratonic lineaments (Colesberg lineament in the west and Thabazimbi-Murchison lineament in the north) may indicate that these lineaments represent suture zones along which the younger domains were accreted during formation of the Kaapvaal Craton. By ∼3 Ga the lithosphere was sufficiently rigid to support development of the Dominion...

Electron spin resonance dating of tooth enamel from Kromdraai B, South Africa

Curnoe, Darren; Grun, Rainer; Thackeray, J
Fonte: Academy of Science of South Africa Publicador: Academy of Science of South Africa
Tipo: Artigo de Revista Científica
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ELECTRON SPIN RESONANCE (ESR) DATING offers the potential to provide dates for Plio-Pleistocene sites in South Africa. Previous attempts have been made to date tooth enamel samples from Sterkfontein, Swartkrans and Gladysvale. Here we report results of ESR dating of tooth enamel from Kromdraai B in the Sterkfontein Valley.

Timing and kinematics of the Colenso Fault: The early Paleozoic shift from collisional to extensional tectonics in the Pan-African Saldania Belt, South Africa

Kisters, Alexander F M; Belcher, Richard W; Armstrong, Richard; Scheepers, Reyno; Rozendaal, Abraham; Jordaan, L Smith
Fonte: Geological Society of South Africa Publicador: Geological Society of South Africa
Tipo: Artigo de Revista Científica
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The Colenso fault is a major northwest to southeast trending fault zone in the Pan-African Saldania Belt of the Western Cape Province in South Africa that is spatially closely associated with granitoids of the ∼550 to 510 Ma Cape Granite Suite. Most of

Age and significance of the Marble Hall breccia, Bushveld Complex, South Africa

De Waal, S.A.; Graham, IT; Phillips, David
Fonte: Geological Society of South Africa Publicador: Geological Society of South Africa
Tipo: Artigo de Revista Científica
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Diorite and associated breccia form scattered outcrops on the Marble Hall Fragment, in the vicinity of the town of Marble Hall, Mpumalanga Province, South Africa. The diorite (2055.6 ± 3.1 Ma) intruded as sub-horizontal sills in highly deformed and metam

Estimating greenhouse gas emissions associated with achieving universal access to electricity for all households in South Africa

Tait,Louise; Winkler,Harald
Fonte: Journal of Energy in Southern Africa Publicador: Journal of Energy in Southern Africa
Tipo: Artigo de Revista Científica Formato: text/html
Publicado em 01/01/2012 EN
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Climate change, energy security and achieving universal electricity access for all households are all pressing issues that South Africa must address. These objectives need not be trade-offs, however, and achieving electricity access for the poor does not justify the building of large coal-fired power stations or threaten South Africa's climate change objectives. This paper estimates the electricity demand from the residential sector to 2020 resulting from universal access, and finds that electricity for low-income households would constitute only a small addition to total electricity demand and would represent only a minor portion of output from the coal-fired power station, Medupi. Furthermore, emissions from the additional electricity consumed by newly connected households would have a negligible impact on South Africa's emissions profile.

A review of carbon dioxide capture and sequestration and the Kyoto Protocol's clean development mechanism and prospects for Southern Africa

Lotz,M; Brent,A C
Fonte: Journal of Energy in Southern Africa Publicador: Journal of Energy in Southern Africa
Tipo: Artigo de Revista Científica Formato: text/html
Publicado em 01/01/2008 EN
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The clean development mechanism (CDM) of the Kyoto Protocol is a financial incentive intended to make economically marginal greenhouse gas (GHG) prevention projects more feasible. Carbon dioxide capture and sequestration (CCS) is a possible GHG mitigating strategy. The Intergovernmental Panel on Climate Change (IPCC) defines a CCS project as a process consisting of three phases: the separation of carbon dioxide from industrial and energy-related sources; transportation of the carbon dioxide to a storage location; and long-term isolation of the carbon dioxide from the atmosphere. This paper focuses on prospects of CCS as CDM projects in general and in the context of Southern Africa. Currently there is no evidence of a long term proven track record of integrated CCS systems; only three industrial scale CCS projects exist globally. Nevertheless, new concepts have been proposed for CCS CDM projects such as long-term liability and certified emission reduction (CER) cancellation. However, these concepts are not in the current CDM framework at present. It is thus difficult to prove CCS as an eligible CDM project without first addressing possible expansion and shortfalls of the current CDM structure. More research is also required to quantify the trade offs presented between mitigating carbon dioxide from the atmosphere at the possible detriment of the areas of storage in the Southern Africa context. Only then may CCS projects be deemed more viable in the CDM context. Finally...

Renewable energy choices and their water requirements in South Africa

Sparks,Debbie; Madhlopa,Amos; Keen,Samantha; Moorlach,Mascha; Dane,Anthony; Krog,Pieter; Dlamini,Thuli
Fonte: Journal of Energy in Southern Africa Publicador: Journal of Energy in Southern Africa
Tipo: Artigo de Revista Científica Formato: text/html
Publicado em 01/11/2014 EN
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South Africa is an arid country, where water supply is often obtained from a distant source. There is increasing pressure on the limited water resources due to economic and population growth, with a concomitant increase in the energy requirement for water production. This problem will be exacerbated by the onset of climate change. Recently, there have been concerns about negative impacts arising from the exploitation of energy resources. In particular, the burning of fossil fuels is significantly contributing to climate change through the emission of carbon dioxide, a major greenhouse gas. In addition, fossil fuels are being depleted, and contributing to decreased energy security. As a result of this, the international community has initiated various interventions, including the transformation of policy and regulatory instruments, to promote sustainable energy. With this in mind, South Africa is making policy and regulatory shifts in line with international developments. Renewable energy is being promoted as one way of achieving sustainable energy provision in the country. However, some issues require scrutiny in order to understand the water footprint of renewable energy production. Due to the large gap that exists between water supply and demand...

Evaluating the impact of consumer behaviour on the performance of domestic solar water heating systems in South Africa

Ijumba,Pamela; Sebitosi,Adoniya Ben
Fonte: Journal of Energy in Southern Africa Publicador: Journal of Energy in Southern Africa
Tipo: Artigo de Revista Científica Formato: text/html
Publicado em 01/01/2010 EN
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South Africa experienced a rapid expansion in the electric power consumer base after 1994 that was not matched by corresponding investment in the country's generation capacity. By the dawn of 2008, the situation had reached a critical point, with regular countrywide blackouts and load shedding and is expected to persist for several years, before the proposed new base stations can come online. Currently, 92% of the country's electricity is generated in coal-based power stations and are responsible for the country's heavy carbon footprint. Additionally this power must crisscross the country to distant load centres via an aging transmission infrastructure and in the process massive amounts of energy are lost particularly during peak power demand. Electricity consumption in South African households accounts for approximately 35% of peak demand, with water heating constituting 40% of that. The country has abundant sunshine and solar water heating technology and offers one of the most viable compiementary solutions to the country's energy and environmental crises. Moreover the location of the systems at the consumer end means that the need to upgrade the transmission infrastructure can also be differed. Application of technology alone however...

Enhancing consumers' voluntary use of small-scale wind turbines to generate their own electricity in South Africa

Whelan,Brendan; Muchapondwa,Edwin
Fonte: Journal of Energy in Southern Africa Publicador: Journal of Energy in Southern Africa
Tipo: Artigo de Revista Científica Formato: text/html
Publicado em 01/01/2011 EN
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This paper investigates whether households and small businesses can voluntarily take advantage of the South Africa's substantial wind resources to produce their own power from small-scale wind turbines in a viable way. The viability of small-scale wind turbines used to displace electricity consumption from the grid is assessed by means of a financial analysis based on the internal rate of return method. The benefits of small-scale wind turbines output is valued at the grid power tariff which is saved rather than at the wind feed-in tariff rate. The analysis found the small-scale wind turbines to be robustly viable in locations with a mean annual wind speed of at least 8m/s, which is only a few of the windiest locations in South Africa. The competiveness of the wind turbines is seriously challenged by the relatively low coal-based electricity tariffs in South Africa. As such, the financial analysis also considers alternative scenarios where the turbines are supported by financial mechanisms, namely: a tariff subsidy; a capital subsidy and revenue from carbon credits. The analysis reveals that a tariff subsidy of between R1.00 and R1.60/kWh or a capital subsidy of between R25.95 and R32.330/kW or a carbon credit price of between R2.135 and R3.200 will be needed to boost the viability of consumer-based small-scale wind turbines in areas with a mean annual wind speed of at least 5m/s...

What contribution does the installation of solar water heaters make towards the alleviation of energy poverty in South Africa?

Wlokas,Holle Linnea
Fonte: Journal of Energy in Southern Africa Publicador: Journal of Energy in Southern Africa
Tipo: Artigo de Revista Científica Formato: text/html
Publicado em 01/01/2011 EN
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The South African government has publicized plans to install one million solar water heaters in households throughout South Africa by the year 2014, with the goals of reducing strain on existing electricity resources, mitigating greenhouse gas emissions, creating employment and alleviating poverty. This paper examines two existing solar water heater installation projects with the aim of investigating the social contribution of the installation of solar water heaters in low-income households in South Africa. The Sustainable Urban Livelihoods approach (SULA) was adjusted to provide an analytical framework for the development of suitable indicators of social change in the context of renewable energies and energy poverty. Increases in household capital and the reduction of household vulnerability to shocks, stressors and seasonal variability as the result of solar water heater installation were investigated in projects in low-income housing developments in the cities of Cape Town and Port Elizabeth, South Africa. Data collected from paired household surveys (before and after installation) in over 600 households and qualitative information (Most Significant Change stories) show that the provision of a constant, cheap source of heated water contributed positively to the alleviation of energy poverty. Household capitals (categorised as Human...

Dissemination of solar water heaters in South Africa

Chang,Keh-Chin; Lin,Wei-Min; Ross,Greg; Chung,Kung-Ming
Fonte: Journal of Energy in Southern Africa Publicador: Journal of Energy in Southern Africa
Tipo: Artigo de Revista Científica Formato: text/html
Publicado em 01/01/2011 EN
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46.51%
Global concern over a looming energy crisis, water scarcity and man-made climate change are driving a huge demand for clean technologies, which focus on preserving the earth's resources. In South Africa, the economy is very energy-intensive with coal being the main national energy supply. In view of the growing depletion of fossil fuel, it is important for South Africa to adopt a more sustainable energy mix. This study examines the potential for widespread dissemination of solar water heaters (SWHs) in South Africa. Barriers and constraints to market expansion are analyzed to determine strategies for overcoming these barriers. It is found that payback period of a SWH is shorter than the life-span of the system itself, indicating that SWHs are economically viable even with low production cost of electricity and thus represent a profitable investment proposition for end users, manufacturers and distributors. However, the subsidy programs offered by the government of South Africa may not be sufficient to facilitate diffusion. This is attributed to the high initial capital cost of the system and low affordability of the majority of the South Africa population with low income. Alternative financing mechanisms are required.

Solar radiation analysis and regression coefficients for the Vhembe Region, Limpopo Province, South Africa

Mulaudzi,Sophie T; Sankaran,Vaithianathaswami; Lysko,Meena D
Fonte: Journal of Energy in Southern Africa Publicador: Journal of Energy in Southern Africa
Tipo: Artigo de Revista Científica Formato: text/html
Publicado em 01/01/2013 EN
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Given the limited observed and reliable data for solar irradiance in rural parts in South Africa, a correlation equation of the Angström-Prescott linear type has been used to estimate the regression coefficients in the Vhembe District, Limpopo Province, South Africa. Five stations were selected for the study, with the greatest distance between stations less than 180 km. Monthly regression coefficients were derived for each station based on an observation dataset of sunshine duration hours and global horizontal irradiance. The correlation coefficients appear to be above 0.9. The representative Angström-Prescott model for the Vhembe Region was found by collating the data for each station and then averaging the respective correlation coefficients. This paper presents the generated regression coefficients for each station and for the Vhembe Region.

Decomposition analysis of energy-related CO2 emissions in South Africa

Zhang,Ming; Dai,Shuang; Song,Yan
Fonte: Journal of Energy in Southern Africa Publicador: Journal of Energy in Southern Africa
Tipo: Artigo de Revista Científica Formato: text/html
Publicado em 01/02/2015 EN
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South Africa has become one of the most developing countries in the world, and its economic growth has occurred along with rising energy-related CO2 emission levels. A deeper understanding of the driving forces governing energy-related CO2 emissions is very important in formulating future policies. The LMDI (Log Mean Divisia Index) method is used to analyse the contribution of the factors which influence energy-related CO2 emissions in South Africa over the period 1993-2011. The main conclusions drawn from the present study may be summarized as follows: the energy intensity effect plays the dominant role in decreasing of CO2 emission, followed by fossil energy structure effect and renewable energy structure effect; the economic activity is a critical factor in the growth of energy-related CO2 emission in South Africa.

Self-reported musculoskeletal pain among dentists in South Africa: A 12-month prevalence study

Botha,PJ; Chikte,U; Barrie,R; Esterhuizen,TM
Fonte: SciELO África do Sul Publicador: SciELO África do Sul
Tipo: Artigo de Revista Científica Formato: text/html
Publicado em // EN
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INTRODUCTION: Musculoskeletal trouble (ache, pain, discomfort) originating in the neck, shoulder, and back is a common occupational hazard among dental professionals worldwide. The significance of this problem justified research into the prevalence of these symptoms among dentists in South Africa for which there is currently no information. AIMS: The aim of this study was to investigate the one-year prevalence of self-reported musculoskeletal trouble in the neck, shoulder, and lower back areas among dentists in South Africa. METHODS: A survey questionnaire was forwarded to all members of the South African Dental Association whose email addresses were recorded on the Association data base. The email survey was performed using the previously validated Nordic Musculoskeletal Questionnaires. RESULTS: This cross sectional study revealed a self-reported 12-month prevalence of musculoskeletal trouble (ache, pain, discomfort) among dentists in South Africa of 77,9% involving the neck, 69,8% the lower back, and 72,4% the shoulders. Multiple regression analysis showed that a decrease in height among the respondents was associated with an increase in neck trouble (0.962 [CI 0.938; 0.992]). CONCLUSIONS: The 12-month prevalences for musculoskeletal trouble (ache...

Small hydropower in southern Africa - an overview of five countries in the region

Klunne,Wim Jonker
Fonte: Journal of Energy in Southern Africa Publicador: Journal of Energy in Southern Africa
Tipo: Artigo de Revista Científica Formato: text/html
Publicado em 01/01/2013 EN
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This paper looks at the status of small hydropower in Lesotho, Mozambique, South Africa, Swaziland and Zimbabwe. For each country, an overview will be given of the electricity sector and the role of hydropower, the potential for small hydropower and the expected future of this technology. Small hydropower has played an important role in the history of providing electricity in the region. After a period with limited interest in applications of small hydropower, in all five countries, a range of stakeholders from policy makers to developers are showing a renewed interest in small hydropower. Although different models were followed, all five countries covered in the paper do currently see activities around grid connected small scale hydropower. Particular frameworks that facilitate IPPs and Power Purchase Agreements with the national utility do provide a basis for (local) commercial banks to provide finance. Off-grid hydropower for rural electrification purposes sees activities in the countries with an active (support) role of government in this respect only. Small hydropower, renewable energy technology has large potential across the southern Africa region, both for grid connected and off-grid applications. Historically, small hydropower played an important role in the development of the region. Since the mid-1960s...