Author:Leigh, L; Helder, D; Behnert, I; Deadman, A; Fox, N; Leloglu, UM; Özen, H; Griffith, DDate:Jul 2011The Tuz Gölü site does demonstrate some challenges for being used as an absolute calibration site. These include: spatial and temporal variability on the order of +/- 0.02, atmospheric transmittance variability on the order of between 0.52 ...Read more
Author:Ramoroka, MT; Masonta, Moshe T; Kliks, ADate:Dec 2015The role of cheap and easy access to various telecommunication facilities is crucial for further community development. Such an observation is of particular importance for the developing countries all over the world since reliable and open ...Read more
Author:Masonta, Moshe T; Lysko, Albert A; Mekuria, FissehaDate:Oct 2012In wireless communication networks, radio frequency spectrum is the most important and very expensive resource. The TV digital
switchover (DSO) will leave a large portion of the TV frequency bands unused, known as TV white space (TVWS). In ...Read more
Author:Louis, DK; Hanson, I; Masonta, Moshe TDate:May 2016This paper introduces the Ghana Technology University College (GTUC) television white space (TVWS) network deployed in Accra, Ghana. The network, which is still work-in-progress, provides Internet connectivity to six Senior High Schools and ...Read more
Author:Mfupe, Luzango P; Mzyece, M; Mekuria, FissehaDate:May 2012Television White Spaces (TVWS) coupled with Dynamic Spectrum Access and Cognitive Radio (DSA-CR) technologies are increasingly viewed as key enablers to the bridging of the digital divide in rural areas. However, in order to realize maximum ...Read more
Author:Lamola, MM; Johnson, David; Lysko, Albert A; Zlobisnky, NatashaDate:Sep 2016Dynamic Spectrum Access (DSA) plays a vital role in opportunistic access to spectrum. A key component of DSA is preventing interference to the incumbent (primary) user from the secondary user. We present the results of an experiment to analyze ...Read more
Author:Lysko, Albert ADate:May 2021This invited talk summarises the key findings related to experimentation with and practics of television white spaces (TVWS).Read more
Author:Forbes, A; Dudley, Angela L; Roux, SDate:Dec 2010Research at the Mathematical Optics Group uses "twisted" light to study new quatum-based information security systems. In order to understand the structure of "twisted" light, it is useful to start with an ordinary light beam with zero twist, ...Read more
Author:Botha, G; Barnard, EDate:Nov 2005Many applications of pattern recognition to natural language processing require large text corpora in a specified language. For many of the languages of the world, such corpora are not readily available, but significant quantities of text are ...Read more
Author:Ntshotsho, PhumzaDate:Oct 2015Ntshotsho and her colleagues sought to verify and characterise success in government’s efforts to restore degraded ecosystems through invasive alien plant management. Invasive alien plants pose a significant threat to South Africa’s biodiversity ...Read more
Author:Ndebele, Bright B; Gledhill, IMADate:Sep 2023The dynamics of two-dimensional vortex shedding from a rotating cluster of three cylinders was investigated using Computational Fluid Dynamics (CFD) and Dynamic Mode Decomposition (DMD). The cluster was formed from three circles with equal ...Read more
Author:Grobler, AJ; Holm, SR; Van Schoor, GDate:Nov 2015(PMSMs) are well suited for high-speed (HS) applications due to their high efficiency, power density, and dynamic response capability. The heat extraction area decreases as the speed increases, making thermal effects more dominant at high ...Read more
Author:Shou, KJ; Napier, JALDate:Sep 1999A new displacement discontinuity method is developed for the analysis of multi-layered elastic media. This approach is based on a novel superposition scheme and the analytical solution to the problem of a displacement discontinuity element ...Read more
Author:Smit GJF; Wilms JM; Diedericks GPJDate:Nov 2010Models that are used for the simulation of two-phase flows in coastal dynamics make extensive use of empirical data. The main focus of this investigation is to develop models for specific aspects of two-phase flows that are based on physical ...Read more
Author:Nabarro, FRNDate:Sep 2000The structure and properties of two families of lattice-coherent composites, those based on gamma' Ni3Al and those based on TiA/Ti3Al, are shown to have strong similarities. The coherent system of cubic/tetragonal Y2O3-stabilized ZrO2 is ...Read more
Author:McLaren, M; Romero, J; Padgett, MJ; Roux, FS; Forbes, ADate:Sep 2013In this paper we consider geometrical two-photon optics of Bessel-Gaussian modes generated in spontaneous parametric down-conversion of a Gaussian pump beam. We provide a general theoretical expression for the orbital angular momentum (OAM) ...Read more
Author:Stewart, TJ; Ittmann, HWDate:1979A study of the economic distribution of maize throughout South Africa is reported. Although the problem of minimizing total transportation costs in such a situation is a classical one, and its solution is well known, there was in this case a ...Read more
Author:Fernandes, PJLDate:Mar 1998This article discusses the outcome of an investigation of the failure of copper tubes from cold water distribution system carrying potable water in a shopping centre. Samples of copper tubes from a cold water distribution system which had ...Read more
Author:De Beer, Morris; Sadzik, EM; Fisher, C; Coetzee, CHDate:Jul 2005This paper addresses the measurement (i.e. “fingerprinting”) of tyre loading and contact stress patterns associated with slow moving test tyres on the new Heavy Vehicle Simulator (HVS Mk IV+) of Gautrans. The two test tyres used on the HVS ...Read more
Author:De Beer, Morris; Fisher, C; Kannemeyer, LDate:Sep 2004The aim of this paper is to highlight the use of SIM (Stress-In-Motion) technology on typical heavy vehicles found at the N3-TCC (Traffic Control Centre), with illustrative examples on real world trucks on this highway. A summary of the ...Read more