A system or subsystem may be termed "safety-critical" if a run-time error or failure can result in death, injury, loss of property, or environmental harm. One approach to building such systems is to eliminate or minimize the probability of hazardous conditions occurring that could lead to accidents. The long-term goal of this research is to provide a methodology, including an integrated tool set; for building such systems that ensures that the risk of harm caused by the computer is acceptable. Previous work has involved formal modeling and analysis procedures for identifying software hazards and safety-critical software requirements, analyzing software requirements for completeness and robustness, verifying and assessing safety, and designing safety into software including run-time support environments and software fault tolerance. This research will extend these techniques to distributed systems and apply the requirements analysis procedures to a family of requirements specification languages. The interactive component involves teaching a graduate course in software reliability and safety, giving guest lectures at area universities, and initiating productive interaction on safety-related work in the field of testing with women faculty and researchers. This project furthers VPW program objectives which are (1) to provide opportunities for women to advance their careers in engineering and in the disciplines of science supported by NSF and (2) to encourage women to pursue careers in science and engineering by providing greater visibility for women scientists and engineers employed in industry, government, and academic institutions. By encouraging the participation of women in science, it is a valuable investment in the Nation's future scientific vitality.
