Page 316 - Practical Design Ships and Floating Structures

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seven inputs. In this manner, the database can be populated with extended data of seakeeping
characteristics for future analysis.

5 DISCUSSION AND CONCLUSION
Consideration of reuse in design is usually related to components. Data reuse, although not
uncommon, is rarely, if ever, discussed. And yet large and reliable databases of design data are often
put together for future use. It can be observed that the use of such databases can be made more
intelligent and rewarding by considering data reuse in a formal manner. It is obvious that it is possible
to have decomposition without reuse and reuse without decomposition, but when used in combination
it opens up new opportunities for either approach.

This paper addresses three common tasks performed by a designer: decomposing design problems into
manageable tasks, applying past experience (knowledge and design data) and extending design
knowledge. The first task relates to decomposition and the latter two to reuse. These tasks are
illustrated through a preliminary ship design example.
The hypergraph partitioning approach used in the example in this paper is able to decompose a design
problem into sub-problems with a minimum number of linking variables (hence co-ordination effort).
Apart from design constraint equations, the hypergraph representation can also be used to model
design activities and variables. The example design problem is decomposed into two sub-problems
using this approach. The division of work shows a sensible pattern. Reuse concepts are then used to
assemble candidate Pareto optimal designs for one of the sub-problems into which the original
problem was decomposed. The reuse concept is then extended to include an associated satellite
application. It is clear, on the basis of the above, that decomposition and data reuse have in-built
capabilities that can be beneficially taken advantage of.

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