Method of Key Rating Ascertainment for Space Software based on Fuzzy Synthetic Evaluation and Quantitative Fault Tree Analysis

Software key rating ascertainment is very important in development of space software. It can guide manager develop the congruent software using the optimal benefit-cost ratio in management. It can also provide the direction in software measurement, and help designer improve system reliability finally. In view of space software characteristics and quantitative data shortage, a method of key rating ascertainment for space software based on fuzzy synthetic evaluation and quantitative fault tree analysis is proposed. The results of application to space software development show that the new approach makes software key rating ascertainment have the quantificational evidence, which is ascertained using quantitative data and qualitative analysis. Keywords-space software; key rating; fuzzy synthetic evaluation; quantitative fault tree analysis (QFTA); bottom event; top event