University of South Africa

About: University of South Africa is a education organization based out in Pretoria, South Africa. It is known for research contribution in the topics: Context (language use) & Population. The organization has 8478 authors who have published 19960 publications receiving 237688 citations. The organization is also known as: Unisa.

Vanadium (V) adsorption isotherms and kinetics using polypyrrole coated magnetized natural zeolite

Abstract: Magnetized natural zeolite-polypyrrole (MZ-PPY) composite as a potential adsorbent for vanadium was prepared via polymerization of pyrrole monomer using FeCl 3 oxidant in aqueous medium in which magnetized natural zeolite particles were suspended. The MZ-PPY composite was characterized by attenuated total reflectance Fourier transform infrared spectroscope (ATR-FTIR), field emission scanning electron microscope (FE-SEM) and high resolution transmission electron microscope (HR-TEM). Batch adsorption studies were performed to test the ability of the adsorbent to remove V(V) ions from aqueous solution. From sorption equilibrium modelling, the equilibrium data is well described by Langmuir, Sips and Redlich–Peterson isotherms while the adsorption kinetics is described by the pseudo-second order model. The Langmuir adsorption capacity is 65.0 mg/g at 298 K. Thermodynamic parameters confirm the spontaneous and endothermic nature of the vanadium adsorption process. Meanwhile V(V) removal process is found not to be affected by co-existing ions. Furthermore, the material can be used in two adsorption cycles without compromising its capacity.

Mapping mixed methods research in library and information science journals in Sub-Saharan Africa 2004–2008

Abstract: The purpose of this article is to explore the use of mixed methods research (MMR) in articles published in library and information science (LIS) journals in Sub-Saharan Africa (SSA) from 2004 to 2008. A mixed methods research framework provided in the methodological literature is used to determine how this method was practiced within the LIS scientific community in SSA. Six hundred and eighty five articles published in nine peer-reviewed LIS journals in SAA were reviewed, finding the dominant research methods in these journals to be survey designs and historical research. The use of MMR was limited: 48 out of 685 articles used the mixed methods approaches that were identified in the methodological literature. A paradigm shift and a change of mindset are recommended for LIS researchers in SSA so that they may exploit the advantages offered by mixed methods research in conducting their studies.

Basic Formal Education Quality, Information Technology and Inclusive Human Development in Sub-Saharan Africa

Abstract: This study assesses the relevance of basic formal education in information technology for inclusive human development in 49 countries in sub-Saharan Africa for the period 2000-2012. The question it aims to answer is the following: what is the relevance of basic formal education in the effect of mobile phone penetration on inclusive human development in sub-Saharan Africa when initial levels of inclusive human development are taken into account? The empirical evidence is based on instrumental quantile regressions. Poor primary education dampens the positive effect of mobile phone penetration on inclusive human development. This main finding should be understood in the perspective that, the education quality indicator represents a policy syndrome because of the way it is computed, notably: the ratio of pupils to teachers. Hence, an increasing ratio indicates decreasing quality of education. It follows that decreasing quality of education dampens the positive effect of mobile phone on inclusive development. This tendency is consistent throughout the conditional distribution of inclusive human development. Policy implications for sustainable development are discussed.

Usability evaluation methods: mind the gaps

Abstract: The strengths and weaknesses of heuristic evaluation have been well researched. Despite known weaknesses, heuristic evaluation is still widely used since formal usability testing (also referred to as empirical user testing) is more costly and time consuming. What has received less attention is the type of information heuristic evaluation conveys in comparison to empirical user testing supported by eye tracking and user observation. If usability methods are combined, it becomes even more important to distinguish the information contribution by each method. This paper investigates the application of two usability evaluation methods, namely heuristic evaluation and empirical user testing supported by eye tracking, to the website of a learning management system with the intent of discovering the difference in the usability information yielded. Heuristic evaluation as an inspection method is accepted to be fundamentally different from empirical user testing. This paper contributes to a deeper understanding of the nature of the differences by identifying the kind of usability problems identified through each method. The findings should be of interest to researchers, designers and usability practitioners involved in website design and evaluation.