Detecting malfunctions at nuclear plants.

Computer-based methods can detect slow-developing malfunctions at nuclear power plants that could cause accidents and temporary plant shutdowns. A research team, lead by Don Miller, chairman of nuclear engineering, Ohio State University, successfully tested an integrated software approach in the training simulator at the Perry Nuclear Plant, about 40 miles east of Cleveland.

"Integrated computer systems will enhance the reliability of a plant by allowing operators to intervene before a fault causes a problem that would trigger the plant's safety systems, automatically shutting a plant down in case of an emergency," he explains.

Nuclear plants are made of up to 80 mechanical and nuclear systems, all monitored by human operators. Because these systems work independently and interactively, the operators sometimes misdiagnose problems in systems that interact, or fail to detect small faults as they are developing.

For example, a mechanical failure in a valve that is circulating water through a boiling water reactor may be difficult for an operator to detect. While this problem may not pose an immediate threat, it could develop into a more serious one. If the fault reaches a critical stage, it will...