Author:Keaikitse, M; Brink, W; Govender, NatashaDate:Oct 2012Object detection is an essential first stage in a surveillance system, primarily because it focuses all the subsequent processes. The
standard approach to object detection is background subtraction. At the core of background subtraction is ...Read more
Author:Kfir, R; Burger, JS; Idema, GKDate:1993Three bays along the South African coast were studied for the presence of Salmonella spp in seawater, effluent and storm water discharges into the bays and in shellfish harvested at the same sites. The microbial quality of water and shellfish ...Read more
Author:Theron, Andre; Engelbrecht, Jeanine; Kemp, J; Kleynhans, Waldo; Turnbull, TDate:Jun 2017Sinkholes are an unpredictable geohazard that endanger life and property in dolomitic terrains. Sinkholes are a significant threat in Gauteng, South Africa’s most populated and urbanized province. Small-scale surface subsidence is frequently ...Read more
Author:Van Schoor, MichaelDate:Jul 2002Sinkholes in dolomitic areas are notoriously difficult geophysical targets, and selecting an appropriate geophysical solution is not straightforward. Electrical resistivity imaging or tomography (RESTOM) is well suited to mapping sinkholes ...Read more
Author:Kruszewska, KJ; Du Cann, VMDate:May 1996Two petrographic methods, namely long-wave fluorescence intensity measurements and a vitrinite elasticity index were developed and used to detect incipient oxidation in coals subjected to simulated weathering conditions. The two methods are ...Read more
Author:Theron, J; Cilliers, Jacques E; Du Preez, M; Brozel, VS; Venter, SNDate:Sep 2000A pit-stop semi-nested PCR assay for the detection of toxigenic Vibrio cholerae in environmental water samples was developed and its performance evaluated. The PCR technique amplifies sequences within the cholera toxin operon specific for ...Read more
Author:Thirlwall, JTDate:Nov 1998The recognition of small features of low contrast in the image recorded by an x-ray image intensifier is usually limited by photon noise. This detail-contrast perceptibility is dependent on the detective quantum efficiency (DQE) and the ...Read more
Author:Hecker, GFK; Van Zyl, MN; Wainwright, EJ; Goosen, P; Heydenrych, CDate:Sep 1997The introduction of new factors of safety for winding ropes is accompanied with codes of practice for the design, operation and maintenance of winders and for the condition assessment of winder ropes. The studies undertaken during this project ...Read more
Author:Van Zyl, MNDate:Nov 1997This volume 2 of the GAP 324 report discusses the parts of the project that dealt with the sinking of very deep shafts, and an initial study into the behaviour of triangular strand ropes for deep shafts.Read more
Author:Van Zyl, MDate:Dec 2000Deep shaft drum winder operations will be allowed if such winder installations comply with the requirements of a code of practice (SABS0294). The specifications of the winder code of practice were largely based on experience, but some uncertainty ...Read more
Author:Hecker, GFK; Wainwright, EJ; Heydenrych, CDate:Jul 1998The objective of this research project was to determine how winder design parameters affect the safe working life of rope operating of drum winders with the view to refine requirements in the code of practice for the performance, operation, ...Read more
Author:Sinclair, BJ; Scott, MB; Klok, CJ; Terblanche, JS; Marshall, DJ; Reyers, B; Chown, SLDate:Sep 2006The distribution and abundance of free-living arthropods from soil and under stones were surveyed at the Cape Hallett ice-free area (ASPA No. 106), North Victoria Land, Antarctica. A total of 327 samples from 67 plots yielded 11 species of ...Read more
Author:Faniso, Zimbini; Griffith, Derek J; Matthews, M; Kravits, JDate:Nov 2017Remote sensing of inland water quality is challenging satellite Earth observation application. Inland water bodies are small, optically complex and dark targets compared to surrounding land. Signal reaching satellites is dominated by light ...Read more
Author:Anochie-Boateng, Joseph; Maina, JWDate:Nov 2013A new and innovative three-dimensional (3-D) laser based technique was employed to accurately determine the morphological (shape) properties of aggregates used in asphalt mixes. The objective of this paper is to investigate the influence of ...Read more
Author:Pretorius, PJ; Linder, PWDate:1998The acid-base properties of hydrous ferric oxide were studied by glass electrode potentiometry. From the potentiometric data, surface protonation constants were derived according to the Diffuse Double Layer convention. Chemical equilibrium ...Read more
Author:Le Roux, Lukas JDate:Sep 2010The work that is presented here is focused on the results that were obtained during studies of the performance of the DSC under certain reverse bias conditions. When one cell in the series connection in a module is shaded, the current will ...Read more