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Koczela, L. J.

Publications and source records attributed to Koczela, L. J..

11 records
All sourcesNASA NTRSDOE OSTI
NASA NTRS1974

Adaptive voting computer system

A computer system is reported that uses adaptive voting to tolerate failures and operates in a fail-operational, fail-safe manner. Each of four computers is individually connected to one of four external input/output (I/O) busses which interface with external subsystems. Each computer is connected to receive input data and commands from the other three computers and to furnish output data commands to the other three computers. An adaptive control apparatus including a voter-comparator-switch (VCS) is provided for each computer to receive signals from each of the computers and permits adaptive voting among the computers to permit the fail-operational, fail-safe operation.

Koczela, L. J.↗
NASA NTRS1971

A three-failure-tolerant computer system.

Two basic factors influence the design of highly reliable computer systems: the amount of failures required to be tol erated and the reliability or MTBF required. A computer system designed to tolerate any three single failures in a fail-operational-fail-operational-fail-safe manner for a real-time control application is presented. The design approach uses adaptive majority voting in both hardware and software with a four-level redundant system. Various methods of performing the adaptive majority voting functions were evaluated with the selected approach using a special module termed a voter-comparator switch (VCS). The VCS module allows the computer system to be operated in a variety of redundant modes, depending on the failure tolerance required at any particular time.

Koczela, L. J.↗
NASA NTRS1970

Concept for a distributed processor computer

Future generation computer utilizes cell of single metal oxide semiconductor wafer containing general purpose processor section and small memory of approximately 512 words of 16 bits each. Cells are organized into groups and groups interconnected to form computer.

Bogue, P. N.↗