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This paper deals with an efficient optimization method of combining fiber orientation and topology for constant-stiffness composite laminated plates. The optimal topology and fiber orientation can be simultaneously obtained, using the proposed method. To overcome the non-monotonous behaviors derived from directly optimizing fiber orientation, the lamination parameters are selected as design variable. The proposed method mainly includes two steps. Initially, lamination parameters and density are taken as the design variables for determining the fiber orientation and topology shape. A combined optimization model is built based on the penalization theory. The optimal lamination parameter and topology shape can be achieved simultaneously in this step. Then, solving nonlinear equations is transformed into a least squares optimization problem. The optimal fiber orientation is obtained and matched with the optimal lamination parameter. Finally, numerical examples of designing short cantilever beam and compliant inverter are performed to illustrate the validity of this method.

A morphing leading edge, based on the compliant mechanism, is a novel concept which can improve the aerodynamic performance of aircraft for different missions. This can obviously reduce the weight and enhance the aircraft’s fuel efficiency. A simultaneous optimization of topology and fiber orientations for a composite leading edge has been achieved in the paper. It mainly included two steps. Initially, the lamination parameters and density were taken as design variables to determinate the fiber angles and topology, respectively. The least squares between the actual and desired displacements at key points were set as the objective function. Under the volume constraints, the combined optimization model of the leading edge was built to simultaneously obtain the optimal lamination parameters and topology shape. Then the optimal fiber angles were matched with the optimal lamination parameters by transforming the nonlinear equations to the least squares optimization. The physical model of the composite leading edge and experiments for it were manufactured and designed. The morphing capability of the composite’s compliant leading edge was investigated through simulation and experiments.

Dynamic changes refer to the modifications of workflow model in which some running instances are executing. When the dynamic changes occur, how to migrate the running instances from old workflow model to new workflow model is one of current research hotspots of workflow management technology. Based on polychromatic sets theory, this article proposes a new workflow dynamic change and instance migration approach for workflow management system. The frequent workflow dynamic changes are modelled and described formally. The workflow region is defined and its recognition algorithm is presented. The current running region and the dynamic change region are recognised and sorted in compound workflow model. According to the position sorting results, the selection of migration policies is implemented. A case study on order processing in manufacturing enterprise is provided to illustrate the feasibility and effectiveness of the workflow dynamic change and instance migration approach. With a formal mathematical foundation, the proposed approach reduces the problem size of workflow dynamic changes, decreases the computing complexity of workflow regions recognition, and has flexibility to take the different migration policies corresponding to the different workflow running instances dynamically.

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