29 research outputs found

    Validation of University of New Brunswick Ionospheric Modeling Technique with ionosonde TEC estimation over South Africa

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    For more than a decade, ionospheric research over South Africa has been carried out using data from ionosondes geographically located at Madimbo (28.38°S, 30.88°E), Grahamstown (33.32°S, 26.50°E), and Louisvale (28.51°S, 21.24°E). The objective has been modelling the bottomside ionospheric characteristics using neural networks. The use of Global Navigation Satellite System (GNSS) data is described as a new technique to monitor the dynamics and variations of the ionosphere over South Africa, with possible future application in high frequency radio communication. For this task, the University of New Brunswick Ionospheric Modelling Technique (UNB-IMT) was applied to compute midday (10:00 UT) GNSS-derived total electron content (GTEC). GTEC values were computed using GNSS data for stations located near ionosondes for the years 2002 and 2005 near solar maximum and minimum, respectively. The GTEC was compared with the midday ionosonde-derived TEC (ITEC) measurements to validate the UNB-IMT results. It was found that the variation trends of GTEC and ITEC over all stations are in good agreement and show a pronounced seasonal variation for the period near solar maximum, with maximum values ( 80 TECU) around autumn and spring equinoxes, and minimum values ( 22 TECU) around winter and summer. Furthermore, the residual ΔTEC = GTEC − ITEC was computed. It was evident that ΔTEC, which is believed to correspond to plasmaspheric electron content, showed a pronounced seasonal variation with maximum values ( 20 TECU) around equinoxes and minimum ( 5 TECU) around winter near solar maximum. The equivalent ionospheric and total slab thicknesses were also computed and comprehensively discussed. The results verified the use of UNB-IMT as one of the tools for future ionospheric TEC research over South Africa

    Fostering institutional existentialism in the search for legitimacy

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    Educational and training institutions functioning in today’s globalized economic landscape find themselves in a situation where they face competition but also interrelatedness and interdependency with other global institutions. This naturally drives these institutions towards the pursuit of legitimacy, which would see its qualifications (and by extension its students) recognized as equal to its/their compeers. Within the field of organizational communication management, a body of literature focuses in on this pursuit of legitimacy, and frames it within an institutional mindset; formally as within institutional theory. Institutional theory, however, when practiced in educational organizations, has the potential to be functionalistic in nature – isolating and manipulating organizational elements to work towards achieving a desired state. In this paper, the institutional mindset of educators and students at the University of South Africa is empirically explored, in order to unpick the functionalistic nature thereof and to suggest alternative ways in which to interpret and implement institutionalism within this context. Herein, the four pillars of institutionalism is conceptually and empirically discussed, offering up considerations as to a more existentialistic approach in their effecting. From this, this paper proposes ways in which institutional existentialism has the potential to balance the perception of globalized legitimacy with contextual validity and authenticity

    Mapping GPS-derived ionospheric Total Electron Content over Southern Africa during different epochs of solar cycle 23

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    The Southern African Development Community and the International Global Navigation Satellite Systems Service (GNSS) network of dual frequency Global Positioning System (GPS) receivers provide an opportunity to determine Total Electron Content (TEC) over Southern Africa by taking advantage of the dispersive nature of the ionospheric medium. For this task, the University of New Brunswick (UNB) ionospheric modelling technique which applies a spatial linear approximation of the vertical TEC above each station using stochastic parameters in Kalman filter estimation, primed with data from the Southern Africa GPS network, was used for mapping TEC at South African locations during selected days and hours of different epochs of solar cycle 23. Significant enhancements in the TEC value and features, which could be associated with frequent solar events, are evident around a day of extreme solar maximum. These observations are discussed and further investigated by analyzing the GOES 8 and 10 satellites X-ray flux (0.1–0.8 nm) and SOHO Solar EUV Monitor (26.0–34.0 nm) higher resolution data. Comparison of these physical quantities reveals that for each X-ray flare observed, there is an associated EUV flare event. The latter phenomenon causes photoionisation in the daytime ionosphere which results in significant TEC enhancement. The daytime UNB TEC compared with the International Reference Ionosphere (IRI) 2001 predicted TEC found both models to show a good agreement

    A Quantitative Study of Principals’ Perceptions During Curriculum Reform in Lesotho

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    Policymakers are continually seeking a reform blueprint that would transform schools into beneficial institutions. Amid these reforms are the principals who drive the implementation of these mandated curriculum reforms. This quantitative study explores the perceptions of primary school principals in Lesotho as they lead the implementation of the integrated curriculum, popularly known as the ‘new curriculum’. The study relies on quantitative data obtained from 83 principals purposively drawn from the Maseru district in Lesotho. The SAS program was used to compute descriptive statistics that were used to interpret the principals’ views using the sense-making framework. The results of this study showed that the principals exhibit high and positive perceptions regarding their roles and responsibilities as leaders of curriculum reform. These results are surprising given that they have neither been prepared nor developed to lead the implementation of this reform. Moreover, their views should be interpreted in light of current literature regarding the implementation of curriculum reforms. This existing literature portrays a gloomy picture regarding the implementation of this reform in Lesotho. This study expands the literature on reform implementation in developing countries such as Lesotho. Future studies should compare the perceptions of the principals with those of the teachers to corroborate the seemingly high scores obtained from the principals’ self-ratings

    Understanding healthcare and population mobility in southern Africa: The case of South Africa

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    The impact of global increases in human mobility on health systems is a little understood but highly political issue in recipient countries. South Africa (SA) is the greatest recipient of migrants from the Southern African Development Community. There is a policy of free primary health care for all in SA – as outlined in the Constitution and the National Health Act – but its interpretation is less inclusive within implementation guidelines and practice.  As a result, non-nationals face access challenges, and public health responses have engaged with migration to a limited extent. Migration provides opportunities for health and economic benefits, and has the potential to positively and negatively affect health systems. To maximise positive impact and mitigate against potential negative consequences requires attention and engagement of policy-makers from health and other sectors, including public health researchers and health workers. We outline our current research and existing responses to migration and health in southern Africa

    The heliospheric modulation of 3-10 Mev electrons: modeling of changes in the solar wind speed in relation to perpendicular polar diffusion

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    Abstract The discrepancy between cosmic ray model predictions representing solar minimum conditions in the heliosphere and the 3-10 MeV post-1998 electrons observations by the Kiel Electron Telescope (KET) onboard Ulysses suggests the need for consistent changes in model parameters with increasing solar activity. In order to reduce this discrepancy, an effort is made to model the KET observations realistically during periods of increased solar activity by applying an advanced three-dimensional, steady-state electron modulation model based on ParkerÕs transport equation including the Jovian electron source. Some elements of the diffusion tensor which were not previously emphasized are revisited. A new relation is also established between the latitudinal dependence of the solar wind speed and the perpendicular polar diffusion. Based on this relation, a transition of an average solar wind speed from solar minimum to solar maximum conditions, as observed on board the Ulysses spacecraft, is modeled on the concept of the time-evolution of large polar coronal holes. These changes are correlated to different scenarios of the enhancement of perpendicular polar diffusion. Effects of these scenarios are illustrated, as a series of steady-state solutions, on the computed 7 MeV Jovian and galactic electrons in comparison with 3-10 MeV electrons observed from the period 1998 to the end of 2003. It is shown that this approach improves compatibility with the KET observations but it also points to the need for a time-dependent electron modulation model to fully describe modulation during moderate to extreme solar maximum conditions

    Language rights, intercultural communication and the law in South Africa

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    This article seeks to explore the present language scenario in courts of law. The article makes use of section 6 of the Constitution of the Republic of South Africa (1996), as a point of departure. At face value this section seems to entrench the language rights of individuals. This would mean that individuals could request trials to be held in their mother tongues, with fluent and competent speakers of that mother tongue sitting on the bench. However, this has not materialised. Contrary to popular opinion, the article argues that individual language rights are to some extent entrenched in the Constitution, but there are no mechanisms to secure such rights in the public domain. The article argues that it is often only language privileges that are preserved in institutions such as the justice system. Legally speaking, there is an obligation on the State to provide interpreters to facilitate access to all eleven official languages in courts of law. This in itself presents numerous challenges. The article argues further that the corollary to this is that there is very little space for intercultural communication in courts of law (as defined by Ting-Toomey, 1999, and Gibson, 2002). There has been little or no capacity building in this regard. It is English, to some extent Afrikaans, and the western cultural paradigm, which prevails. The result is further communication breakdown and language intolerance. In this article, the notion of language rights in courts of law is explored against the backdrop of existing theories of intercultural communication
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