Now showing items 558-565 of 565

    • Water-only laboratory coal fractionation using the reflux classifier 

      Campbell, Q.P.; Le Roux, M.; Smith, I.G.T. (Elsevier, 2015)
      Due to health and environmental factors involved with standard float-sink analytical methods, a water-only fractionation procedure was investigated. A laboratory scale 105 × 105 mm reflux classifier was built and used to ...
    • Where is the power of the IEEE 1459-2010 

      Rens, Johan; Van Rooyen, Tian; De Jager, Francois (IEEE, 2014)
      The integration of the IEEE 1459-2010 power definitions with the IEC 61000-4-30 PQ standard is investigated. A Class A PQ instrument, which record network coherent data with an absolute time uncertainty of less than 100 ...
    • White space and digital dividends: the case for dynamic spectrum access in South Africa 

      Ferreira, Melvin; Helberg, Albert (IEEE, 2011)
      In this paper we present the current state of affairs surrounding the analog switch-off and corresponding digital dividend as pertaining to South Africa. Analog switch-off and digital dividends has enjoyed much attention ...
    • Wing-body circulation control by means of a fuselage trailing edge 

      Huyssen, R.J.; Spedding, G.R.; Mathews, E.H.; Liebenberg, L. (American Institute of Aeronautics & Astronatics, 2012)
      Ideal flight sheds the least amount of kinetic energy into a wake while imparting momentum sufficient to balance the vehicle weight. This combination defines a unique downwash distribution for the wake, which an aircraft ...
    • A wireless sensor network testbed for the evaluation of energy-aware routing schemes 

      Grobler, Magdalena J.; Marais, Henri-Jean; Krige, Joubert G. J. (Hindawi, 2014)
      Wireless sensor networks (WSNs) are receiving a lot of research attention due to continual improvement in the technologies used by these networks. The energy efficiency of sensor nodes and the network as a whole is of ...
    • X-ray diffraction parameters and reaction rate modeling for gasification and combustion of chars derived from inertinite-rich coals 

      Everson, Raymond C.; Okolo, Gregory N.; Neomagus, Hein W.J.P.; Dos Santos, Jaen-Mari (ELSEVIER, 2013)
      An investigation was undertaken to determine the effect of carbon structural properties on the reactivity of chars derived from inertinite-rich coal. The structures of chars were characterized by X-ray diffraction and ...
    • µ-Analysis applied to self-sensing active magnetic bearings 

      Van Schoor, George; Van Vuuren, Pieter Andries (SAIEE Publications, 2011)
      The stability margin of a two degree-of-freedom self-sensing active magnetic bearing (AMB) is estimated by means of µ-analysis. The specific self-sensing algorithm implemented in this study is the direct current measurement ...
    • μ-Analysis applied to self-sensing active magnetic bearings 

      Van Vuuren, P.A.; Van Schoor, G. (SAIEEE, 2011)
      The stability margin of a two degree-of-freedom self-sensing active magnetic bearing (AMB) is estimated by means of μ -analysis. The specific self-sensing algorithm implemented in this study is the direct current ...