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Extensibility in ORDBMS databases : an exploration of the data cartridge mechanism in Oracle9i

- Ndakunda, Tulimevava Kaunapawa

Authors: Ndakunda, Tulimevava Kaunapawa
Date: 2013-06-18
Subjects: Database management , Oracle (Computer file)
Language: English
Type: Thesis , Masters , MSc
Identifier: vital:4686 , http://hdl.handle.net/10962/d1008098 , Database management , Oracle (Computer file)
Description: To support current and emerging database applications, Object-Relational Database Management Systems (ORDBMS) provide mechanisms to extend the data storage capabilities and the functionality of the database with application-specific types and methods. Using these mechanisms, the database may contain user-defined data types, large objects (LOBs), external procedures, extensible indexing, query optimisation techniques and other features that are treated in the same way as built-in database features . The many extensibility options provided by the ORDBMS, however, raise several implementation challenges that are not always obvious. This thesis examines a few of the key challenges that arise when extending Oracle database with new functionality. To realise the potential of extensibility in Oracle, the thesis used the problem area of image retrieval as the main test domain. Current research efforts in image retrieval are lagging behind the required retrieval, but are continuously improving. As better retrieval techniques become available, it is important that they are integrated into the available database systems to facilitate improved retrieval. The thesis also reports on the practical experiences gained from integrating an extensible indexing scenario. Sample scenarios are integrated in Oracle9i database using the data cartridge mechanism, which allows Oracle database functionality to be extended with new functional components. The integration demonstrates how additional functionality may be effectively applied to both general and specialised domains in the database. It also reveals alternative design options that allow data cartridge developers, most of who are not database server experts, to extend the database. The thesis is concluded with some of the key observations and options that designers must consider when extending the database with new functionality. The main challenges for developers are the learning curve required to understand the data cartridge framework and the ability to adapt already developed code within the constraints of the data cartridge using the provided extensibility APls. Maximum reusability relies on making good choices for the basic functions, out of which specialised functions can be built. , KMBT_363 , Adobe Acrobat 9.54 Paper Capture Plug-in
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Service provisioning in two open-source SIP implementation, cinema and vocal

- Hsieh, Ming Chih

Authors: Hsieh, Ming Chih
Date: 2013-06-18
Subjects: Real-time data processing , Computer network protocols , Internet telephony , Digital telephone systems , Communication -- Technological innovations
Language: English
Type: Thesis , Masters , MSc
Identifier: vital:4687 , http://hdl.handle.net/10962/d1008195 , Real-time data processing , Computer network protocols , Internet telephony , Digital telephone systems , Communication -- Technological innovations
Description: The distribution of real-time multimedia streams is seen nowadays as the next step forward for the Internet. One of the most obvious uses of such streams is to support telephony over the Internet, replacing and improving traditional telephony. This thesis investigates the development and deployment of services in two Internet telephony environments, namely CINEMA (Columbia InterNet Extensible Multimedia Architecture) and VOCAL (Vovida Open Communication Application Library), both based on the Session Initiation Protocol (SIP) and open-sourced. A classification of services is proposed, which divides services into two large groups: basic and advanced services. Basic services are services such as making point-to-point calls, registering with the server and making calls via the server. Any other service is considered an advanced service. Advanced services are defined by four categories: Call Related, Interactive, Internetworking and Hybrid. New services were implemented for the Call Related, Interactive and Internetworking categories. First, features involving call blocking, call screening and missed calls were implemented in the two environments in order to investigate Call-related services. Next, a notification feature was implemented in both environments in order to investigate Interactive services. Finally, a translator between MGCP and SIP was developed to investigate an Internetworking service in the VOCAL environment. The practical implementation of the new features just described was used to answer questions about the location of the services, as well as the level of required expertise and the ease or difficulty experienced in creating services in each of the two environments. , KMBT_363 , Adobe Acrobat 9.54 Paper Capture Plug-in
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The functioning of the interbank market and its significance in the transmission of monetary policy

- De Angelis, Catherine

Authors: De Angelis, Catherine
Date: 2013-06-11
Subjects: South African Reserve Bank , Monetary policy -- South Africa , Foreign exchange rates -- South Africa , Money market -- South Africa , Banks and banking -- South Africa , Repurchase agreements -- South Africa , South Africa -- Economic policy , South Africa -- Economic conditions
Language: English
Type: Thesis , Masters , MCom
Identifier: vital:1075 , http://hdl.handle.net/10962/d1008054 , South African Reserve Bank , Monetary policy -- South Africa , Foreign exchange rates -- South Africa , Money market -- South Africa , Banks and banking -- South Africa , Repurchase agreements -- South Africa , South Africa -- Economic policy , South Africa -- Economic conditions
Description: Monetary policy in South African is the primary means by which the authorities can influence activity in the overall economy. The South African Reserve Bank accommodates banks through repo transactions for which they charge the repo rate. The most important market in the transmission of the repo rate to the rest of the economy is the interbank market. As such, a detailed discussion of this market is given. In September 200 I the monetary authorities made certain adjustments to the repo system of accommodation, which included changing the repo rate from a floating rate to a fixed rate that would be administratively determined by the MPC. This was done to address certain weaknesses in the floating rate system. This thesis examines and compares the period before and after the adjustments to the repo system, with the aim of determining whether or not the monetary authorities achieved the goals intended from making this change. The repo rate, prime interbank rate, 3-month NCO rate and the prime lending rate are analysed using the Engle-Granger two variable approach and an ECM model to test for causality. It was found that the monetary authorities did not achieve their intended goals as the relationship between the repo rate and the interbank rate was more significant in the first period. Furthermore, the direction of causality the authorities hoped to achieve by implementing the changes were in fact already in place. As such the adjustments to the system changed the transmission mechanism from the one desired by the authorities to one that was not intended. The conclusions reached by this study show that, in terms of the objectives of the monetary authorities, the previous repo system functioned better. , KMBT_363 , Adobe Acrobat 9.54 Paper Capture Plug-in
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Use of the internet in newsgathering : a case study of The Post newspaper in Zambia

- Hamachila, Alphonsius

Authors: Hamachila, Alphonsius
Date: 2013-06-10
Subjects: Post (Lusaka, Zambia) Electronic news gathering -- Zambia -- Case studies Journalism -- Data processing -- Zambia -- Case studies Reporters and reporting -- Zambia -- Case studies
Language: English
Type: Thesis , Masters , MA
Identifier: vital:3518 , http://hdl.handle.net/10962/d1008075
Description: The Internet and World Wide Web have become dominant newsgathering tools in a sholi period of time. While the body of research, particularly in the First World, has developed quickly along with the Web, many unanswered questions remain on how journalists in developing countries make use of the Internet for newsgathering purposes. This study combined social constructivist theory with the socio-organisational and cultural approaches to news production in order to critically investigate how journalists at The Post newspaper in Zambia relate to, and make use of, the Internet as a newsgathering resource, in the context of Third World conditions. The study critiqued technological detelminism perspectives on journalists' use of the new information technology. The technological determinism theory, which has largely been advanced by some scholars from the developed world, takes a celebratory approach to journalists' use of the Internet in the newsroom. Using qualitative semi-structured interviews and observations, the study established that while journalists at The Post acknowledged the lnternet's potential in news gathering, factors such as unreliable telecommunications infrastructure, poor Internet skills, lack of local content on the World Wide Web, and organisational and occupational demands inhibited the use of the Internet as a journalistic newsgathering resource. The study established further that online reporting is only a tool within the broader news gathering and production process; and in the case of The Post, it does not replace the traditional news gathering techniques used by journalists, particularly direct contacts with human sources. The respondents cited face-to-face interviews, a traditional means of newsgathering, as the main driving force in news gathering routines at the newspaper. However, although the respondents saw some mixed blessings in the Internet as a reporting tool, they also believed that the benefits outweighed the problems. , KMBT_363 , Adobe Acrobat 9.54 Paper Capture Plug-in
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Environmental policy processes surrounding South Africa's plastic bags regulations : tensions, debates and responses in waste product regulation

- Nhamo, Godwell

Authors: Nhamo, Godwell
Date: 2013-06-07
Subjects: Environmental policy -- South Africa Plastic bags -- Law and legislation -- South Africa Environmental protection -- South Africa Environmental law -- South Africa Waste products -- South Africa Refuse and refuse disposal -- South Africa
Language: English
Type: Thesis , Doctoral , PhD
Identifier: vital:1944 , http://hdl.handle.net/10962/d1008051
Description: This study was conducted in South Africa. South Africa is the first country within the Southern African Development Community to have regulated plastic shopping bags waste through the imposition of both a standard on thickness and a levy. Given this scenario, the Plastic Bags Regulations present an illustrative case for researching complexity, uncertainty and controversies surrounding a new trend in environmental policy making, namely waste product regulation. The thesis focuses on understanding and investigating tensions, debates and responses emerging from the policy process as actors and actor-networks put not only the Plastic Bags Regulations asfocal actant (token) but also other actants and actant-networks as well. To this end, a research question that addressed environmental policies, tensions, debates and responses that informed the development of South Africa's Plastic Bags Regulations was spelt out. The research objectives included the need to: (I) analyse selected international environmental policy processes surrounding plastic shopping bags litter and waste regulation and how these influenced developments in South Africa; (2) identify actors, actants and actor/actant-networks that shaped and were being transformed by South Africa's Plastic Bags Regulations and explain the tensions, debates and responses arising in the policy processes; (3) identify environmental policy outputs and assess outcomes emerging from the formulation and implementation of South Africa's Plastic Bags Regulations; and (4) establish patterns in environmental policy process reforms around South Africa's Plastic Bags Regulations. The language of actors (human), actants (non-human) and actor/actant-networks brings to the fore the aspects of processes and relationships that exist around them. As such, insights from the actor/actant-network theory (AANT) were drawn upon to inform the research. AANT enquiry framework collapses binaries such as nature/society, art/science, structure/agency and global/local historically associated with a particular type of social theory. AANT also denies that purely technical, scientific or social relations are possible (the notion of quaSi-objects or token). Data sets were generated following' the Plastic Bags Regulations as token actant with time frames ranging from prior to, during and after the formulation of the regulations. Similarly, data analysis drew insights from AANT's four moments of translation namely problematisation, interessement, enrolment and mobilisation, with the intervention theory providing an evaluative perspective that complemented AANT. The findings were that after the promulgation of the first draft of the Plastic Bags Regulations in May 2000, tensions emerged around the nature of regulation (whether command and control - preferred by government or self regulation - preferred by industry and labour). In this regard the latter group raised concerns about jobs, income and equipment loss as well as the need to have a holistic approach to waste management rather than targeting a single product at a time whilst the former maintained that this would not be so. As such, education, awareness and stringent antilitter penalties were proposed by industry and labour as sustainable responses to the problem of plastic shopping bags waste rather than regulation. These debates continued and resulted in minor amendments to the original regulations as finalised by Government in May 2002. However, industry and labour continued lobbying government resulting in the conclusion of the Plastic Bags Agreement in September 2002 and the ultimate repulsion of the May 2002 regulations in May 2003. As revealed by this research, these responses led to broader social responses and further tensions as demand for plastic shopping bags went down by about 80% although an estimated 1000 jobs were lost and a number of companies lost equipment and business (with some closing down) following the implementation of the regulations. During implementation, debates emerged around the need to promote locally made carry facilities with two alternatives in sight namely: the Green Bag and the Biodegradable Plastic Bag. Debates also took place regarding enforcement of the new law resulting in the amendments of various pieces of legislation including the Environmental Conservation Act, Environmental Management Act and the Revenue Laws Act. Overall, a 15-year policy reform cycle and sub-cycles was determined. The research also established that the government considered the regulations a success and was already implementing simi lar initiatives to regulate other waste products, among them, used tyres, used oil and glass, confirming the trend towards waste product regulation in South Africa. From these research findings, a series of conceptual frameworks were drawn up to clarify the nature of tensions, debates and responses surrounding certain lead actors, actants and actorlactant-networks. Some of the conceptual frameworks that emerged around the actors and actor-networks include Organised Government, Organised Industry and Organised Labour. Conceptual frameworks that emerged around key actants and actant-networks include the Integrated Pollution and Waste Management, Plastic Bags Regulations as well as the discourses surrounding the Green bag and biodegradable plastic bags. The thesis concludes by reflecting on how the above and the grand actor/actant-network conceptual frameworks emerging from this research might be adopted with varying degrees of flexibility to research environmental and waste management policy processes in different waste product regulation set-ups. , KMBT_363 , Adobe Acrobat 9.54 Paper Capture Plug-in
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Five unpublished coins of Alexander the Great and his successors in the Rhodes University Collection

- Snowball, Jeanette D, Snowball, Warren D

Authors: Snowball, Jeanette D , Snowball, Warren D
Date: 2012
Language: English
Type: text , article
Identifier: http://hdl.handle.net/10962/68489 , vital:29267 , http://dx.doi.org/10.7445/50-0-73
Description: Publisher version , The article briefly discusses the economic and political significance of the Alexander III (“the Great”) type silver tetradrachm and publishes three of his coins currently held by the Rhodes University Classics Museum. Based on stylistic elements, they are classified as from the Amphipolis and Arados mints and were probably minted during his lifetime. Two further tetradrachms from the empires of Alexander’s successors, Ptolemy II and Seleucus IV, are also published.
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"Fit for purpose": towards tracking the quality of university education of entry-level journalists

- Berger, Guy

Authors: Berger, Guy
Date: 2010
Language: English
Type: text , article
Identifier: http://hdl.handle.net/10962/159835 , vital:40348 , DOI: 10.1080/02560054.2005.9653329
Description: Debate about the extent to which university education should serve industry is an important consideration for institutions of higher learning in a transforming South Africa, and particularly for those teaching would-be journalists. This issue can also be profitably analysed with reference to the current framework of the South African education authorities who argue that the quality of higher education institutions should be measured in terms of their “fit for purpose” to missions aligned to stakeholder interests in the transformation of the country as a whole. This criterion for quality assessment tends to focus on the educative processes within a university, but it can be argued that it ought to extend into the examination of the output consequences of journalism teaching. This would amount to not just fitness for purpose, but also achievement of purpose – and the latter including a creative and critical impact.
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Aspects of the reproductive biology of monkfish Lophius vomerinus off Namibia

- Maartens, Lima, Booth, Anthony J

Authors: Maartens, Lima , Booth, Anthony J
Date: 2010
Language: English
Type: text , article
Identifier: http://hdl.handle.net/10962/123831 , vital:35504 , https://doi.10.2989/18142320509504090
Description: Aspects of the reproductive biology of monkfish Lophius vomerinus are described from material collected during hake Merluccius spp. biomass surveys and from commercial monkfish and sole Austroglossus microlepis vessels between January 1996 and June 2000 off Namibia at depths between 97m and 686m. Length-at-50% sexual maturity for males and females were estimated at 39.9cm and 58.2cm respectively, males maturing faster than females. The adult sex ratio of fish >50cm total length was strongly biased towards females. There was reproductive activity throughout the year, peaking slightly between autumn and spring.
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Growth, reproduction and population structure of Diplotaxodon limnothrissa in the southeast arm of Lake Malawi

- Kanyerere, Geoffrey Z, Weyl, Olaf L F, Booth, Anthony J

Authors: Kanyerere, Geoffrey Z , Weyl, Olaf L F , Booth, Anthony J
Date: 2010
Language: English
Type: text , article
Identifier: http://hdl.handle.net/10962/124583 , vital:35633 , https://doi.org/10.2989/16085910509503832
Description: With a surface area of ca 28 800km2, Lake Malawi (9°30’S–14°30’S) is the second largest of the African Rift Valley lakes, supporting at least 500, and possibly 2 000, fish species (Turner 1995). The ichthyofauna is dominated by haplochomine cichlids, most of which are confined to the demersal and littoral zones. As a result of over-fishing, the abundance of many of these species has declined (Turner 1994a, 1995, Bulirani et al. 1999, Allison et al. 2002). In contrast, the lake’s offshore fish stocks are considered to be unexploited or only lightly exploited (Thompson and Allison 1997, Turner et al. 2000) and the redirection of fishing effort to these stocks is a high priority (Thompson and Allison 1997, Turner et al. 2000, Allison et al. 2002). Consequently, the Malawi government is currently collaborating with the African Development Bank to develop the deepwater/ offshore fishery in order to increase yields by an estimated 11 000 tons (MC Banda, National Research co-ordinator, pers. comm.). The most abundant cichlid species in the pelagic zone is the small (<210mm TL) zooplanktivorous Diplotaxodon limnothrissa (Turner 1994, Thompson and Allison 1997). It has been recorded throughout the lake at depths ranging from 20 metres down to the anoxic zone at ca 220 metres (Turner 1994b, Thompson et al. 1996, Duponchelle et al. 2000a) and it makes up ca 52% to the total fish biomass (Thompson and Allison 1997). Diplotaxodon limnothrissa will therefore be a major target species in the pelagic fishery, and already comprises in excess of 50% of the mid-water trawl fishery in the southeast arm (SEA) of the lake (Turner 1996).
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Reproductive biology of a riverine cyprinid, Labeo umbratus (Teleostei: Cyprinidae), in small South African reservoirs

- Potts, Warren M, Booth, Anthony J, Hecht, Thomas, Andrew, Timothy G

Authors: Potts, Warren M , Booth, Anthony J , Hecht, Thomas , Andrew, Timothy G
Date: 2010
Language: English
Type: text , article
Identifier: http://hdl.handle.net/10962/125854 , vital:35826 , https://doi.10.2989/16085910509503849
Description: The reproductive and recruitment characteristics of moggel, Labeo umbratus, populations were examined in four small South African reservoirs. Reproduction, characterised by an extended spawning season, high fecundity, short incubation time and rapid larval development, appears to be ideally suited to the highly variable environment of small reservoirs. Evidence suggested that L. umbratus spawns in the reservoirs. In two reservoirs where samples were conducted monthly, GSI (gonado-somatic index) was positively correlated with both water temperature and day length, whilst the CPUE (catch per unit effort) of juveniles was not related to any environmental variable. The success of moggel spawning appeared to increase when there was early spring and consistent summer rainfall.
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Growing of trees in home-gardens by rural households in the Eastern Cape and Limpopo Provinces, South Africa:

- Shackleton, Charlie M, Paumgarten, Fiona, Cocks, Michelle L

Authors: Shackleton, Charlie M , Paumgarten, Fiona , Cocks, Michelle L
Date: 2009
Language: English
Type: text , article
Identifier: http://hdl.handle.net/10962/141360 , vital:37965 , DOI: 10.1080/13504500509469647
Description: Trees provide a wide range of goods and services to rural households which, when incorporated into their livelihood strategies, help reduce their vulnerability to adversity. Governments and policy makers often ignore the contribution made by trees and consequently resources are focussed on cash crops and livestock. Villagers in the Eastern Cape and Limpopo Province, South Africa utilise a range of trees from home-gardens for various purposes, although predominantly for fruit and shade. Trees are either planted or actively retained in households' home-gardens. There were noticeable differences between the villages in the Eastern Cape and those in Limpopo Province, particularly with respect to the overall density of trees per hectare and the number of species per household, both being significantly greater in Limpopo Province. The five most preferred species were listed for each village, revealing a preference for exotic fruit trees in Limpopo Province and a mix of exotic fruit trees and shade trees in the Eastern Cape. Households also retained useful indigenous species, predominantly fruit-bearing species. A range of factors constrain tree growing in home-gardens and households engage in practices to grow and maintain their trees. Not all of these constraints and practices were significantly different between the various localities.
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Some (more) features of conversation amongst women friends:

- Hunt, Sally

Authors: Hunt, Sally
Date: 2009
Language: English
Type: text , article
Identifier: http://hdl.handle.net/10962/139149 , vital:37709 , DOI: 10.2989/16073610509486400
Description: This paper provides an analysis of a conversation between young women friends, which is analysed in terms of Coates’ (1988; 1997; 1999) work on the features of conversation amongst female friends. Coates identifies a number of features which, she says, are typical of conversation between (adult) female friends: a domestic setting, female participants, topics relating to people and feelings, and various formal features including smooth topic development, frequent minimal responses, supportive forms of simultaneous speech and epistemic modality (‘softening’ strategies, including tag questions) (Coates, 1988: 97). The overarching function, she claims, is one of solidarity-building and support: ‘the maintenance of good social relationships’ and ‘the reaffirming and strengthening of friendship’ (Coates, 1988: 98). While this last feature, the function of conversation between women friends, is borne out by the extract to be analysed, the participants in my study utilise different strategies to accomplish it and, in several respects, do not utilise the other features Coates claims to be typical. The research shows, through a detailed analysis of a nineminute extract from a conversation between three women friends, that the features assumed by Coates to be central conversational strategies in the building of female friendship are not the only ways for women to accomplish this function.
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Bycatch and discarding in the South African demersal trawl fishery

- Walmsley, Sarah A, Leslie, Rob W, Sauer, Warwick H H

Authors: Walmsley, Sarah A , Leslie, Rob W , Sauer, Warwick H H
Date: 2007
Language: English
Type: text , article
Identifier: http://hdl.handle.net/10962/123944 , vital:35518 , https://doi.10.1016/j.fishres.2007.03.002
Description: Observers aboard commercial trawlers collected data on the total catch composition of 614 and 479 hauls made by vessels operating off the south and west coasts of South Africa, respectively. On the south coast, four fishing areas were identified on the basis of target species and fishing depth. On the west coast, hauls were separated into those targeting hake Merluccius spp. in four depth ranges (0–300, 301–400, 401–500, and >500 m) and those targeting monkfish Lophius vomerinus. For each area, the catch composition was calculated and the species assemblages were investigated using cluster analysis and multi-dimensional scaling. Finally, for each coast, the weight of fish discarded annually was estimated. On the south coast, although hake dominated, between 21% and 47% of the catch was not hake, depending on the fishing area. In comparison, hake dominated west coast catches, the proportion of hake increasing with depth. For each fishery investigated, approximately 90% of the catch was processed and landed. However, estimates of annual discards indicate that the south and west coast fisheries may annually discard 9000 or 10,000 t and 17,000 or 25,000 t, of undersized and unutilizable fish and offal, respectively, depending on the estimation method used. When developing strategies to limit or enhance utilization of bycatch, cognisance should be taken of the differences in catch composition between the south and west coasts and of the importance of bycatch revenue to south coast fishing companies.
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Accuracy of the activation energy calculated from a thermoluminescence glow‐peak using a method that uses three points on the peak

- Ogundare, F O, Chithambo, Makaiko L

Authors: Ogundare, F O , Chithambo, Makaiko L
Date: 2006
Language: English
Type: text , article
Identifier: http://hdl.handle.net/10962/123016 , vital:35397 , https://doi:10.1002/pssc.200521077
Description: The utility of thermoluminescence (TL) in detecting changes in defect concentration in insulators is well established [1–3]. The underlying premise leading to the emission of TL is that exposure of a material to ionizing radiation causes a redistribution of charge in defect centres within the material. When the material is heated at a controlled linear rate, the thermoluminescence is emitted as a temperature-dependent set of peaks collectively known as a glow-curve. The shape and intensity of each of the glow-peaks may be characterized by a set of parameters consisting of the activation energy E, the frequency factors, the number of electrons n0 trapped in defect centres at the start of the heating, and the order of kinetics b. The order of kinetics b is an indication of the retrapping probability i.e. the probability that a free electron from the conduction band will be retrapped rather than recombine with a hole at a recombination centre to produce thermoluminescence. Retrapping of electrons reduces the TL intensity at any particular temperature during the heating process. The physical mechanisms of TL associated with a given glow curve are unique and may be characterized by analysis of the glow-curve for the said kinetic parameters.
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Trade and the environmental Kuznets curve: is Southern Africa a pollution haven?

- Nahman, Anton, Antrobus, Geoffrey G

Authors: Nahman, Anton , Antrobus, Geoffrey G
Date: 2006
Language: English
Type: text , article
Identifier: http://hdl.handle.net/10962/143202 , vital:38210 , DOI: 10.1111/j.1813-6982.2005.00055.x
Description: Evidence that the environmental Kuznets curve (EKC) may be explained by trade patterns casts doubt on the oft‐stated conclusion that economic growth automatically leads to environmental improvement. Trends in net exports as a proportion of consumption for both USA and UK trade with SACU were examined for various dirty industries. Some evidence of pollution haven effects is found, although a similar trend for clean industries suggests that this effect is weak. However, even a general shift in manufacturing industries from North to South (as opposed to a shift in specifically dirty industries) may explain the EKC to some extent.
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