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Water Exclusion is a new optional feature of AIG algorithm added to TULIP. This removes the water area from the intersection region of AIG to give a more accurate representation of target's location. This reduces the size of the intersection region, the centroid --which is used as a location estimate for the target-- however, may not be closer to the actual target. This is illustrated in the examples below.
Examples
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In this case the centroid is in water and 134km away from target. The green marker shows the actual target's location | With water exclusion the AIG centroid (red) is closer to the target with an error of 78km |