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In this paper, a workflow model based on N-tree for process management in PDM system is presented. It streamlines circuits in process management to sequence, branch, parallel, and loop patterns. It also offers this workflow model’s mechanisms of construction, executing, and state transition by definitions of workflow’s node properties, node constraints and state set. Last it exhibits an instance of applying this workflow model to process management of a simple PDM system.

Aiming at the coupling of traffic laws and traffic participants in the current smart car decision-making process, and the lack of systematic processing of traffic laws, this paper proposes an optimal driving behavior decision-making method based on multi-objective optimization. This paper uses a multi-objective optimization method to establish macro path following indicators, collision risk indicators, traffic efficiency evaluation indicators, and driving burden evaluation indicators to solve the problem of convergence to local solutions and divergence when the existing methods are solved. In addition, the evaluation of the macro path followability is established to ensure that the selected area meets the macro path. In the collision risk assessment, the method based on the hidden Markov model is used to identify the driving intention of the target car, and establish lane occupancy characteristics to determine the risk of collision and the possibility of movement based on the statistical characteristics of the driving habits of object cars. After verification and comparison with existing methods, the optimal driving behavior decision method proposed in this paper is effective and performs well.

The workflow management, in which the main line is the product, is used widely. The emergence of product structure makes workflow management more complex. This thesis focuses on the realization method of workflow engine based on product structure. Firstly, this paper describes the formal definition of the workflow based on product structure, and then gives the algorithm of instantiating workflow, the startup algorithms and the advance algorithms involved in the workflow execution in detail, finally, this paper shows the realization of the engine based on these algorithms. These algorithms described in this paper allow users to make decisions on designing and establishing the composition of the product structure flexible, to define the approval process of the task node flexible, and to advance the process according to the results of the instantiation automatically.