Mohammed Eltahir's blog

Introduction Thissen polygon is a local interpolators that uses nearest neighbours, as they are of high importance ‘first low of geography’. It gives a quick understanding of the space, and starts by defining a search area around the point being process. The space is divided by polygons with each polygon containing one indiviual point. polygons represent that any location inside it, is closer to the point other than any sample point, Also the size of the polygon depend on the point density. Methodology Using QGIS, Thissen polygon (Voronoi) was applied to data of Sudan Admissions and localities that were obtained from (humenreponse.org). North Darfur was the state of application. A comparison between two different ways of splitting the vector was held, and another comparison between the (GRASS and QGIS Geoalgorithms) Voronoi algorithms. Practice Pre-processing: Downloaded the data. Organized on a folder to ease understanding and management. Add data (vector data) to the QGIS environ

Introduction : Using satellites in fish harvesting is due to the great advantages they provide such as the wide range capture of see surface “large coverage”, temporal resolution and data are independent from weather. So that remote sensing has real impact on uncovering the relationship between fish distribution and surrounding environment. The main objective of using remote sensing is to reduce search time and increase catch rate. There are two methods to apply remote sensing data: Indirect Method: measuring oceanographic and environmental factors that correlate with fish habitat, such as ocean colour, sea surface temperature (SST), wind stress, current data, and other environmental characteristic that affect fish habitat Also, known the fact that fish correlate with nutrient-rich waters. Direct method: by spotting fish appearance.  Measuring the environmental factors is much easier than spotting the appearance of a fish. And the main source for fisheries management is thermal inf