response of extremely complicated structures. A paper by Dr R. Goodman, Lloyds Register of Shipping, outlined the engineering philosophy behind their integrated structural design system, which made use of mathematical models for the simulation of the ocean environment and the ship response to this environment. The modular concept of this system allows the user a greater degree of flexibility compared with the more traditional forms of ship structural design.
Flexibility was the major feature in the development of a two-dimensional package for finite element analysis utilizing interactive minicomputers presented by Professor H. A. Kamel of the University of Arizona. The system divides the analysis operation into small segments each of which has its own editing facility. This system allows moderate structural analysis to be performed by minicomputer and larger tasks to be initiated on a minicomputer with the major processing being carried out on a large timesharing computer. By dividing the finite dement analysis into several steps the user is always conscious of the progress of'the task, which leads to better control of the process and greater economy.
Typical of the integrated production design systems was BRITSHIPS presented by Dr R. Hurst of the British Ship Research Association. The modular construction of BRITSHIPS allows the present facilities of shell plate development, ordering and production control and the postprocessing of numerically controlled equipment to be extended to include preliminary and detailed structural design.
At present, the major area of numerically controlled operations in shipyard hull construction has been in the flamecutting of steel plating. A significant effort is being made to extend the range of computer controlled operation in the shipbuilding process. In the HI-CUBE system developed by the Hitachi shipbuilding and Engineering Co., the entire operation of the transportation of materials by conveyors up to the after-treatment of the cut plate is