Formal Modeling And Analysis For Verification Validation And Accreditation Process

With the increasing complexity of simulation system, Verification Validation and Accreditation (VV&A) has become more and more complicated. It will take a lot of time and efforts if all the work is done manually. Workflow divides the work into well-defined tasks and roles, and carries out these tasks by corresponding rules, which can make VV&A process work automatically, improve efficiency and reduce operating costs. This paper stays focus on workflow in VV&A process, and the following aspects have been studied.Firstly, as for the complexity of VV&A process, the complicated and various interacting between VV&A agents, and lacking of necessary guidance and specifications of VV&A process, this paper analyzed the classical workflow modeling methods. Activity network diagram is incorporated into VV&A process, and a novel formal modeling approach called VPFlow is presented for VV&A process. This new method can specify VV&A process and guide VV&A agents to achieve their goals accurately and efficiently.Secondly, VV&A work is very complex, which brings a lot of difficulties for analysis of the VV&A process model. This paper using Petri net briefly studied three anomalous structures, deadlock, lack of synchronization and endless loop, and proposed the corresponding amendments at first. And then it mainly researched the characteristics of VV&A process model, combined equivalent transformation method with Markov method together and presented a novel idea for performance analysis, which is used to analyze VV&A workflow model time performance, resource utilization rate and cost. This new method is the basis of evaluating and optimizing VV&A workflow model.Finally, VV&A process, this complex system engineering, contains many complicated activities and tasks. It will result in heavy workload, low efficiency and poor accuracy if all the work is carried out manually. Computers as the auxiliary are needed to make VV&A process work automatically. On the basis of VV&A process modeling and performance analysis, this paper has designed and developed a VV&A process modeling and analyzing assistant tool VPMAT, which is used to assist VV&A agents to manage and analyze VV&A process efficiently and accurately. VPMAT, the tool for VV&A work, has improved its efficiency and realized automatic work process.