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The GE, Navy, and Air Force Example

    Here's a hypothetical example. Imagine that the Navy, the Air Force and General Electric have separately developed standards for databases containing facts about prices of jet engines and parts. But these standards are not the same. Suppose that associated with each item is a price. Suppose further

1. For GE, the price is a retail price not including spare parts.

2. For the Navy, the price is the Government's purchase price including spare parts.

3. For the Air Force, the price includes additional inventory costs. It includes spare parts but a different assortment than the Navy's.

Now suppose that associated with each database are many programs that use the information. For example, General Electric can compute the cost of equipment packages taking into account discounts. The Navy can compute the economic ordering quantity for use when supplies get low.

Suppose now that some plan requires that unexpectedly a certain item made by General Electric is required in large quantity by both the Navy and the Air Force and deliveries and purchases from various General Electric warehouses have to be scheduled in co-ordination. The context in which the reasoning is done requires the lifting of various information from the contexts of the separate databases to the reasoning context. In the course of this lifting, the sentences representing the information are translated into new forms appropriate for the reasoning context.

Sasa Buvac
Sun Jul 12 14:45:30 PDT 1998