Academy of Science of South Africa (ASSAf): Open Journal Systems
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THE CONFLICT BETWEEN CERTAIN CAPITAL ALLOWANCES IN THE INCOME TAX ACT AND THE SPECIAL ECONOMIC ZONES POLICY OBJECTIVES
No full textThrough various incentives, special economic zones (SEZs) aim to promote industrial capacity development, create jobs and stimulate the South African economy. However, in practice, misalignment of tax legislation requirements with current practices may undermine the success of the SEZ programme. If property developers are unable to claim capital allowances for expenditure incurred on property developments within an SEZ, this acts as a disincentive to investment, which conflicts with the overarching rationale for the SEZ initiative. This study seeks to determine the extent to which current practices prevent property developers from claiming capital allowances for developments in SEZs, and to propose appropriate remedies. The study presents a doctrinal analysis of the requirements of the SEZ Act and relevant provisions of the Income Tax Act in the context of current practices in SEZ development. The analysis demonstrates that, where the ownership of land designated for SEZ development is retained by government, property developer lessees may be unable to claim capital allowances in respect of expenditure incurred on property developments. This study therefore motivates for the removal of the ownership requirement from building allowance provisions of the Income Tax Act. This would align tax legislation with current practice and the policy objectives of the SEZ programme, as well as address the current inconsistency in the requirements of building allowances
Reproductive Performance of Extensively Managed Beef Heifers Mated at 14 Or 26 Months in the Central Bushveld Bioregion
No full textIn South Africa, little local information is available on the value of early mating of extensively kept beef heifers. In contrast, international information is mainly restricted to dairy cattle and intensive production systems. The research was undertaken to evaluate the calving percentage of Bonsmara heifers mated for the first time in an extensively managed beef herd at either 14 or 26 months. Fifty percent of the heifers were mated at 14 months, while the other 50% were mated at 26 months of age for 90 days during the summer mating season (January to March). The research was conducted over six years (2009 to 2014). A 23 factorial analysis of variance (ANOVA) was performed using the six years as block replications. This was done because different animals were evaluated every year. The calving percentage of heifers mated at 26 months was significantly higher than heifers mated at 14 months. From the current study, it seems unlikely that mating heifers at 14 months of age can improve on the traditional extensive system of mating heifers at 26 months on natural veld in the Central Bushveld Bioregion
Knowledge Validation and Nutritional Qualities of Fodder Trees Browsed by Goats in the Gumela Rural Area in Limpopo Province, South Africa
No full textIn sub-Saharan Africa, goat farming has shown to be a significant intervention in the fight against poverty. However, the productivity of goats is threatened by several challenges, such as limited forage availability, especially during dry seasons when the quantity and quality decline. The study aimed to gather smallholder farmers' knowledge on the identity and nutritional qualities of fodder trees browsed by goats in the study area. Fourteen smallholder goat farmers were interviewed using a semi-structured questionnaire. Botanical identification and nutritional analysis of mentioned browse plants were conducted at the Animal Production Laboratory, University of Limpopo, South Africa. Capparis tomentose, Euclea crispa and Cassine transvaalensis had higher (p<0.05) dry matter content. Ziziphus mucronata had higher (p<0.05) ash content. Maerua angolensis had higher (p<0.05) crude protein content, while Colophospermum mopane had a higher (p<0.05) energy content. Colophospermum mopane was ranked the most browsed plant (43%), whereas Ziziphus mucronata and Maerua angolensis were ranked the least browsed plants. Colophospermum mopane and Sclerocarya birrea were classified as bad sources of goat feed. Most of the identified feed materials had crude protein and energy levels higher than the recommended minimum required levels for the maintenance of essential functions of goats.
A lifecycle-based evaluation of greenhouse gas emissions from the plastics industry in South Africa
No full textIncreased production rates of plastic and limited disposal methods have fed concerns regarding environmental degradation. Whilst most of the focus is on plastic litter and marine pollution, greenhouse gas emissions of plastic over its value chains are also of interest and non-trivial at the global scale. To quantify the global warming potential of the local plastics industry, a lifecycle-based carbon footprint is presented encompassing activities such as resource extraction, polymer production and conversion, recycling, and disposal stages. The South African plastics sector is estimated to have emitted 15.8 Mt CO2 eq in 2015, with the granulate production stage bearing the highest environmental load. The consumption of fossil fuel based electricity and the burning of plastic waste also contribute notably to the overall emissions. Additionally, the recycling process in 2015 saved approximately 1.4 Mt of greenhouse gas emissions.Significance:
Research has typically focused on the environmental impacts of the end-of-life stage of plastics, namely disposal and recycling. Despite growing concern, the global warming potential of the local plastics sector across its value chain has not been investigated.
Greenhouse gas emissions arising from the South African plastic sector are non-trivial and are estimated to total 15.8 Mt CO2 eq in 2015.
Amongst the lifecycle stages, the resin production process had the highest contribution in South Africa due to the country’s coal-based monomer production process
The scientific community accepts marram grass to be non-invasive in dune stabilisation in the Cape
No full textModelling NO2 emissions from Eskom’s coal fired power stations using Generalised Linear Models
No full textThe aim of this paper is to determine if a Generalised Linear Model (GLM) is a better model over the traditional simple linear regression when fitted to nitrogen dioxide (NO2) emitted into the atmosphere during the production of electricity from 13 Eskom’s coal fuelled power stations. A GLM was fitted to the NO2 emission data using forward and backward selection of variables for the models. A similar model using regression analysis was fitted for comparison. The results show that a GLM can be used to predict and explain NO2 emissions from coal fired electricity stations in South Africa. The Lognormal model was found to be the better model by diagnostic measures including plots that showed improved variance behaviour in the residuals. Various variables such as amount of electricity sent out (in GWhs), age of power station (in years), power station used, and interaction terms such as electricity and station, Age and station can be used in describing/ predicting NO2 emissions (in tons) from Eskom’s coal fuelled power stations
Evaluating 3D human face reconstruction from a frontal 2D image, focusing on facial regions associated with foetal alcohol syndrome
No full textFoetal alcohol syndrome (FAS) is a preventable condition caused by maternal alcohol consumption during pregnancy. The FAS facial phenotype is an important factor for diagnosis, alongside central nervous system impairments and growth abnormalities. Current methods for analysing the FAS facial phenotype rely on 3D facial image data, obtained from costly and complex surface scanning devices. An alternative is to use 2D images, which are easy to acquire with a digital camera or smart phone. However, 2D images lack the geometric accuracy required for accurate facial shape analysis. Our research offers a solution through the reconstruction of 3D human faces from single or multiple 2D images. We have developed a framework for evaluating 3D human face reconstruction from a single-input 2D image using a 3D face model for potential use in FAS assessment. We first built a generative morphable model of the face from a database of registered 3D face scans with diverse skin tones. Then we applied this model to reconstruct 3D face surfaces from single frontal images using a model-driven sampling algorithm. The accuracy of the predicted 3D face shapes was evaluated in terms of surface reconstruction error and the accuracy of FAS-relevant landmark locations and distances. Results show an average root mean square error of 2.62 mm. Our framework has the potential to estimate 3D landmark positions for parts of the face associated with the FAS facial phenotype. Future work aims to improve on the accuracy and adapt the approach for use in clinical settings.
Significance:
Our study presents a framework for constructing and evaluating a 3D face model from 2D face scans and evaluating the accuracy of 3D face shape predictions from single images. The results indicate low generalisation error and comparability to other studies. The reconstructions also provide insight into specific regions of the face relevant to FAS diagnosis. The proposed approach presents a potential cost-effective and easily accessible imaging tool for FAS screening, yet its clinical application needs further research
Evaluating the utility of facial identification information: Accuracy versus precision
No full textFacial identification evidence obtained from eyewitnesses, such as person descriptions and facial composites, plays a fundamental role in criminal investigations and is regularly regarded as valuable evidence for apprehending and prosecuting perpetrators. However, the reliability of such facial identification information is often queried. Person descriptions are frequently reported in the research literature as being vague and generalisable, whilst facial composites often exhibit a poor likeness to an intended target face. This raises questions regarding the accuracy of eyewitness facial identification information and its ability to facilitate efficient searches for unknown perpetrators of crimes. More specifically, it questions whether individuals, blind to the appearance of a perpetrator of a crime (i.e. the public), can correctly identify the intended target face conveyed by facial identification information recalled from eyewitness memory, and which of the two traditional facial identification formats would be better relied upon by law enforcement to enable such searches. To investigate this, in the current study (N=167) we employed two metrics – identification accuracy and identification precision – to assess the utility of different formats of eyewitness facial identification information in enabling participants to correctly identify an unknown target face across three different formats: facial descriptions, facial composites and computer-generated description-based synthetic faces. A statistically significant main effect for the format of facial identification information on identification accuracy (p<0.001) was found, with a higher target identification accuracy yielded by facial descriptions in comparison to composites and description-based synthetic faces. However, the reverse relationship was established for identification precision, where composites and description-based synthetic faces enabled significantly greater precision in the narrowing down of a suspect pool than did facial descriptions, but did not necessarily result in the retainment of the intended target face (p<0.001).
Significance:
This study highlights the relative importance of person descriptions in being as effective as, if not better than, facial composites in allowing for accurate identifications when solely relying upon eyewitness facial identification information to facilitate the search for unknown perpetrators.
We introduce the metric of identification precision to evaluate the utility of facial identification information obtained by eyewitnesses.
The study provides a novel approach to directly model facial composites based on a person description using traditional fourth-generation composite systems, thus producing a computer-generated description-based synthetic face that resembles a target face observed by an eyewitness
The impacts of artificial light at night in Africa: Prospects for a research agenda
No full textArtificial light at night (ALAN) has increasingly been recognised as one of the world’s most pernicious global change drivers that can negatively impact both human and environmental health. However, when compared to work elsewhere, the dearth of research into the mapping, expansion trajectories and consequences of ALAN in Africa is a surprising oversight by its research community. Here, we outline the scope of ALAN research and elucidate key areas in which the African research community could usefully accelerate work in this field. These areas particularly relate to how African conditions present underappreciated caveats to the quantification of ALAN, that the continent experiences unique challenges associated with ALAN, and that these also pose scientific opportunities to understanding its health and environmental impacts. As Africa is still relatively free from the high levels of ALAN found elsewhere, exciting possibilities exist to shape the continent’s developmental trajectories to mitigate ALAN impacts and help ensure the prosperity of its people and environment.
Significance:
We show that the African research community can usefully accelerate work into understudied aspects of ALAN, which demonstrably impacts human and environmental health. Africa presents a unique, and in places challenging, research environment to advance understanding of this global change driver
