A SOS reliability evaluate approach based on GERT

Since SOS (system-of-systems) has properties of independence, connectivity, attribution, diversity, and em ergent etc., traditional reliability modeling and assessment approaches are not fully suitable to SOS. Typically, SOS is task-oriented and a specified task of SOS will generate a particular logic process. Therefore, the reliability of a SOS can be evaluated by assessing the SOS tasks process. First, this paper uses ABM (Activity Based Methodology) method, which is based on DODAF (Department of Defense Architecture Framework), to decompose a SOS task into activity models. Second, a GERT (Graphical Evaluation and Re view Technique) hierarchical stochastic network is used to describe task process of SOS, which is dynamic and stochastic. Third, a reliability assessment method of SOS based on the SOS task process DES (Discrete Event Simulation) is presented. At last, a case study is given to illustrate the method.