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DSM Partitioning
Partitioning is the process of manipulating (i.e. reordering) the DSM rows and columns such that the new DSM arrangement does not contain any feedback marks. Thus, transforming the DSM into a lower triangular form. For complex engineering systems, it is highly unlikely that simple row and column manipulation will result in a lower triangular form. Therefore, the analyst's objective changes from eliminating the feedback marks to moving them as close as possible to the diagonal (this form of the matrix is known as block triangular). In doing so, fewer system elements will be involved in the iteration cycle resulting in a faster development process.
There are several approaches used in DSM partitioning. However, they are all similar with a difference in how do they identify cycles (loops or ciruits) of information. All partitioning algorithms proceed as follows:
1. Identify system elements (or tasks) that can be determined (or executed) without input from the rest of the elements in the matrix. Those elements can easily be identified by observing an empty row in the DSM. Place those elements in the top of the DSM. Once an element is rearranged, it is removed from the DSM (with all its corresponding marks) and step 1 is repeated on the remaining elements.
2. Identify system elements (or tasks) that deliver no information to other elements in the matrix. Those elements can easily be identified by observing an empty column in the DSM. Place those elements in the bottom of the DSM. Once an element is rearranged, it is removed from the DSM (with all its corresponding marks) and step 2 is repeated on the remaining elements.
3. If after steps 1 and 2 there are no remaining elements in the DSM, then the matrix is completely partitioned; otherwise, the remaining elements contain information circuits (at least one).
4. Determine the circuits by one of the following methods:
5. Collapse the elements involved in a single circuit into one representative
element and go to step 1.
Some other DSM partitioning methods
A. The Reachability Matrix Method
B. Triangularization
Algorithm
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