Augustinus J. van Zyl

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—Human settlement expansion is one of the most pervasive forms of land-cover change in South Africa. The use of Page's cumulative sum (CUSUM) test is proposed as a method to detect new settlement developments in areas that were previously covered by natural vegetation using 500-m Moderate Resolution Imaging Spectroradiometer time-series satellite data. The(More)
Three minimum-error land cover classifiers are compared on coarse resolution MODerate-resolution Imaging Spectrora-diometer (MODIS) surface reflectance data for discerning between vegetation and settlement classes. It is shown that good class separability can be achieved using only the seasonal component of Normalized Difference Vegetation Index (NDVI)(More)
—In this paper, a first order MODIS time series simulator, which uses a Colored Simple Harmonic Oscillator, is proposed. The simulated data can be used to augment data sets so that data intensive classification and change detection algorithms can be applied without enlarging the available ground truth data sets. The simulator's validity is tested by(More)
In this paper a sequential time-varying maximum likelihood classifier is applied on coarse resolution MODIS surface re-flectance data. It is shown that good class separability can be obtained after considering only one year of data. Finally it is shown that after NDVI, band 2 has the highest separabil-ity of all the MODIS land bands, and band 6 has the(More)
It is proposed that a dynamic Bayesian network (DBN) is used to perform turbo equalization in a system transmitting information over a Rayleigh fading multipath channel. The DBN turbo equalizer (DBN-TE) is modeled on a single directed acyclic graph by relaxing the Markov assumption and allowing weak connections to past and future states. Its complexity is(More)
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