A vertically partitioned structure for the design and implementation of object-oriented systems is proposed, and their performance is demonstrated. It is shown that the application-independent portion of the execution overheads in object-oriented systems can be less than the application-independent overheads in conventionally organized systems built on layered structures. Vertical partitioning implements objects through extended type managers. Two key design concepts result in performance improvement: object semantics can be used in the state management functions of an object type and atomicity is maintained at the type manager boundaries providing efficient recovery points. The performance evaluation is based on a case study of a simple but nontrivial distributed real-time system application.>

A high-speed parallel adder of digitally represented numbers called the conditional-sum early completion adder (CSCA) will be described. The CSCA design is based on the computation of "conditional" sums, carries, and column completion detection logic.