Abstract: Methods, systems, and apparatus, including computer programs encoded on a computer storage medium, for updating a molecular database. In one aspect, a method comprises: receiving a request to update a target molecule component stored in the molecular database; updating the data defining a target molecule represented by the target molecule component; identifying a set of target component links that reference the target molecule component; identifying, for each of the target component links, a respective validation criterion associated with the target component link; determining, for each of the target component links, a new validation status for the target component link by evaluating the validation criterion associated with the target component link; and updating the current validation status of each target component link to the new validation status for the target component link.

Abstract: Viewshed intersection analysis and usage is disclosed. A plurality of object positions is obtained. Each object position is associated with a range. A relevant area is determined. Elevation data is obtained for a plurality of points in the relevant area. Lines of sight are evaluated between the plurality of points and the object positions within the associated ranges based on the elevation data. An interest zone comprising a subset of the plurality of points within the relevant area is determined.

Abstract: Viewshed intersection analysis and usage is disclosed. A plurality of object positions is obtained. Each object position is associated with a range. A relevant area is determined. Elevation data is obtained for a plurality of points in the relevant area. Lines of sight are evaluated between the plurality of points and the object positions within the associated ranges based on the elevation data. An interest zone comprising a subset of the plurality of points within the relevant area is determined.