1,720,955 research outputs found
A comparative study of household recycling behaviour in the City of Johannesburg
Full text linkM.Sc. (Environmental Management)Abstract: The City of Johannesburg (CoJ) faces a number of challenges that includes the increase in solid waste generation rates due to the increase of the population in the city. The CoJ also have the problem of finding additional space for more landfill sites as existing landfill sites only have a limited lifespan remaining. Recycling of waste is one option that can be considered to improve solid waste management and hence improve waste management practises. South Africa aims to have all households to recycle their domestic waste by 2016. The key to achieve the household recycling targets is to increase the participation of households to recycle the domestic waste they produce. Knowing which personal or household attributes are associated with high/low recycling behaviour can assist in designing programs to encourage higher participation. Socio-economic characteristics of households were identified as the aspects that can influence an individual’s decision to engage in recycling activities. This main objective of this dissertation is to investigate the recycling behaviour of different socio-economic groups in the CoJ. The key to achieve the aim of this study is to determine factors that encourages or constrains households’ participation in recycling. Specific focus is placed on households of learners attending three selected schools within the CoJ, namely Hoërskool Vorentoe, Helpmekaar Kollege and Trinityhouse High School. These schools were selected as a result of the socio-economic characteristics of their surrounding feeder suburbs. Vorentoe Hoёrskool was classified as low to middle income with Trinity House and Helpmekaar High Schools as middle to high income. Research questionnaires were used for the purpose of this study. The questionnaires were distributed to learners who were requested to have their parents complete it. Results from this study often differed from previous studies on socio-economic factors and recycling in that it is demonstrated by this research that socio-economic factors do not have a material effect on the level of recycling. This study also illustrates that there is a clear willingness to participate in recycling. However, more information and education is needed in order for this willingness to be realised. This study has clearly shown that by implementing certain measures and providing information may possibly increase household recycling rates in the CoJ. Very specific strategies needs to be employed by local authorities’ to increase household recycling rates in the CoJ
Greenhouse gas emissions assessment for electricity generation from coal : an Eskom power station
Full text linkAbstract: Global Greenhouse Gas (GHG) emissions are projected to increase to 36.7 billion metric tonnes in 2020 due to economic development specifically in developing countries as the demand for energy sources continue to increase. The combustion of fossil fuels for electricity generation is the largest contributor to global CO2 emissions. A total share of CO2 emissions from electricity generation have increased steadily over the past 40 years. Coal-fired power stations generate electricity from converting chemical energy stored in fossil fuels into electrical energy. In the conversion process, carbon contained in the fuel is oxidised releasing GHG emissions and other air pollutants into the atmosphere. GHG emitted during electricity generation are dependent on the characteristics of the fuel used during combustion. In the latest GHG emissions inventory published by the Department of Environment, electricity generation accounted for more than 50 per cent of the total emissions resulting from the combustion of coal. South Africa is dependent on coal for electricity generation mainly due to the abundance of coal reserves and affordability. The main aim of this study was to assess and analyse GHG emissions generated from an Eskom coal-fired power station. This study covered an assessment period of seven years, i.e. 2006 to 2012. The trends for the assessment periods were analysed using methodologies from Eskom and the IPCC guidelines. The results showed that there is a correlation between the amount and type of fuel combusted for electricity generation and GHG emitted. Total fuel (e.g. coal, oil, etc.) combusted at the power station for electricity generation was the main parameter used to estimate GHG emissions. During fossil fuel combustion for electricity generation, GHG are emitted in the form of carbon dioxide (CO2), methane (CH4), and nitrous oxide (N2O). In this study, CO2 emissions accounted for the majority of emissions when compared to other gases for the seven year assessment period. Trends for the seven year assessment period varied throughout the years, overall GHG emissions from the coal-fired power station increased by 1.12 per cent from 2006 to 2012. The total GHG emissions measured from the coal-fired power station was 193, 099 GgCO2eq, with coal consumption contributing more than 99 per cent and fuel oil accounting for less than 1.0 per cent of these levels. Specifically, the total CO2, N2O and CH4 emissions measured were 192, 254 GgCO2eq, 804 GgCO2eq and 42 GgCO2eq respectively. This study shows how much of the three GHG (CO2, CH4 and N2O) are emitted during the combustion of coal for the generation of electricity. Furthermore as more coal is burnt to meet the electricity needs of the country, GHG emissions will likely continue to increase in the future hence South Africa should focus its climate change mitigation efforts on this sector.M.Sc. (Environmental Management
Going Beyond Counting First Authors in Author Co-citation Analysis
Full text linkThe present study examines one of the fundamental aspects of author co-citation analysis (ACA) - the way co-citation
counts are defined. Co-citation counting provides the data on which all subsequent statistical analyses and mappings
are based, and we compare ACA results based on two different types of co-citation counting - the traditional type that
only counts the first one among a cited work's authors on the one hand and a non-traditional type that takes into
account the first 5 authors of a cited work on the other hand. Results indicate that the picture produced through this non-traditional author co-citation counting contains more coherent author groups and is therefore considerably clearer. However, this picture represents fewer specialties in the research field being studied than that produced through the traditional first-author co-citation counting when the same number of top-ranked authors is selected and analyzed. Reasons for these effects are discussed
Variations on the Author
Full text link“Variations on the Author” discusses two of Eduardo Coutinho’s recent films (Um Dia na Vida, from 2010, and Últimas Conversas, posthumously released in 2015) and their contribution to the general question of documentary authorship. The director’s filmography is characterized by a consistent yet self-effacing form of authorial self-inscription: Coutinho often features as an interviewer that rather than express opinions propels discourses; an interviewer that is good at listening. This mode of self-inscription characterizes him as an author who is not expressive but who is nonetheless markedly present on the screen. In Um Dia na Vida, however, Coutinho is completely absent form the image, while Últimas Conversas, on the contrary, includes a confessional prologue that moves the director from the margins to the center of his films. This article examines the ways in which these works stand out in the filmography of a director who offers new insights into the notion of cinematic authorship
Appropriate Similarity Measures for Author Cocitation Analysis
Full text linkWe provide a number of new insights into the methodological discussion about author cocitation analysis. We first argue that the use of the Pearson correlation for measuring the similarity between authors’ cocitation profiles is not very satisfactory. We then discuss what kind of similarity measures may be used as an alternative to the Pearson correlation. We consider three similarity measures in particular. One is the well-known cosine. The other two similarity measures have not been used before in the bibliometric literature. Finally, we show by means of an example that our findings have a high practical relevance.information science;Pearson correlation;cosine;similarity measure;author cocitation analysis
Dispelling the Myths Behind First-author Citation Counts
Full text linkWe conducted a full-scale evaluative citation analysis study of scholars in the XML research field to explore just how different from each other author rankings resulting from different citation counting methods actually are, and to demonstrate the capability of emerging data and tools on the Web in supporting more realistic citation counting methods. Our results contest some common arguments for the continued
use of first-author citation counts in the evaluation of scholars, such as high correlations between author rankings by first-author citation counts and other citation
counting methods, and high costs of using more realistic citation counting methods that are not well-supported by the ISI databases. It is argued that increasingly available digital full text research papers make it possible for citation analysis studies to go beyond what the ISI databases have directly supported and to employ more
sophisticated methods
koamabayili/VECTRON-author-checklist: VECTRON author checklist
No full textWe have done our best to complete the author checklist relating to the use of animals in the hut study. Note that the objective for the hut study was to evaluate the IRS treatment applications for residual efficacy against Anopheles mosquitoes, including the local An. coluzzii mosquito population. Cows were only used to attract mosquitoes into the huts and no tests were carried out directly on the cows. The author checklist is intended for use with studies where experiments are carried out on animals, which is why we have had such difficulty in completing this for the hut study, as many of the questions do not relate to how the cows were used
Author-wise bibliometric analysis based on entropy.
No full textAuthor-wise bibliometric analysis based on entropy.</p
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