SLAMorris Final Thesis After Corrections.pdf - Cranfield University

On examination of the training set 72% of the subrecords were contiguous;
therefore it appears likely that once a subrecord header is identified the
remainder of the record would contiguously follow it. In the remaining 28% of
subrecords were fragmented a maximum of twice; the fragments were spread
across the storage media. Without further knowledge of the storage structure it
would not be possible to form a relationship between the fragments. In these
circumstances producing every valid combination provided a maximum of 42
results for each visual thumbnail. Out of the images produced a maximum of 11
resulted in full visual thumbnails which could be viewed using a standard image
viewer. Therefore an analyst could manually go through the resulting images
along with the logs and decide what evidence if any to produce.
To calculate the asymptotic computational complexity of this research an
analysis of the implementation was performed using the same approach as
Section 9.4.2. For this method f(n) the number of computational steps was
calculated to be:
f(n) = 6n! + 34n 2 + 116n 1 + 75c*n 0
where:
n represents the number of fragments being evaluated by the method
c represents a constant processing time
When f(n) is converted into a standardised polynomial with the constants
removed the function becomes:
f(n) = 6n! + 34n 2 + 116n 1 + 75
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