Abstract: A parallel processing architecture and method, based on the 3D Algebra Reconstruction Technique (ART), for iteratively reconstructing from cone beam projection data a 3D voxel data set V representing an image of an object. The cone beam projection data is acquired by employing a cone beam x-ray source and a two-dimensional array detector to scan the object along a source scanning trajectory to obtain, at each of a plurality of discrete source positions .theta..sub.i on the source scanning trajectory, a 2D measured cone beam pixel data set P.sub.i. The 3D voxel data set V is subdivided into or organized as a plurality m of independent voxel subcubes V.sup.0 through V.sup.m-1 each containing a plurality of voxels. As a result of the subdivision of the 3D voxel data set V into voxel subcubes, the 2D measured cone beam pixel data set P.sub.i (measured projection data array) is correspondingly subdivided for each source position .theta..sub.

Abstract: A database shadowing system for performing data checkout/checkin operations. The system includes performing the steps of 1) identifying a data item stored in a database for editing, 2) copying the data item from the database to an active memory file thereby creating an active memory copy of the data item, 3) associating a tag with the active memory copy of the data item, changing a state of the data item 4) tag depending upon the edit operation performed on the active memory copy of the data item, and 5) saving any change made to the active memory copy of the data item by making the change to the database data item upon issuance of a save command, so that the data item tag of the active memory copy of the data item controls the manner of changing the database data item.

Abstract: The present invention, in one embodiment, is a method for representing component connectivity of components which compose a system. The method comprises the steps of creating a diagram composed of blocks representing components of the system, representing connectivity of the components on the diagram, selected a first start component, assigning a first label to the start component, identifying respective children components of the start component, assigning the respective children components of start component respective labels, the respective labels being unique for each component and representing the component connectivity, selecting another start component if any components in the diagram are unlabelled, and then repeating the above steps for the second start component. The process is repeated until the components and component connectivity are represented in a respective label. The assigned component labels are then stored.