Optimization problems are approached using mean field annealing (MFA), which is a deterministic approximation, using mean field theory and based on Peierls's inequality, to simulated annealing. The MFA mathematics are applied to three different objective function examples. In each case, MFA produces a minimization algorithm that is a type of graduated nonconvexity. When applied to the ;weak-membrane' objective, MFA results in an algorithm qualitatively identical to the published GNC algorithm. One of the examples, MFA applied to a piecewise-constant objective function, is then compared experimentally with the corresponding GNC weak-membrane algorithm. The mathematics of MFA are shown to provide a powerful and general tool for deriving optimization algorithms.

In situations in which computers are used to manage life-critical situations, software errors that could arise due to inadequate or incomplete testing cannot be tolerated. This paper examines three methods of creating fault-tolerant software systems, Recovery Block, N-Version Programming, and Consensus Recovery Block, and it presents reliability models for each. The models are used to show that one method, the Consensus Recovery Block, is more reliable than the other two.

An interface for digital computers and peripherals is described in this paper. The design process is traced, beginning with the definition of the problem environment, and the derivation of primitive interfacing functions. The functions are associated with four functional classes; data input/output, data storage, data manipulation, and control. Interface capabilities range from control over the synchronization of input and output pulse data to control over the data word widths acceptable. System limitations include technical, timing, and synchronization problems. The interface is modular, generalized, and user programmable. The control is contained in two levels: a user microprogram, and a read only nanoprogram.

Combinational networks with no internal fan-out are considered from the point of view of testing for multiple faults. Several different approaches utilizing added inputs and observable outputs are considered and the tradeoffs are discussed.