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With the deployment of internet of things-based monitoring terminals, massive electric measurement data are transmitted and shared among different grid company sectors. Consortium blockchain based consensus process has been adopted to enhance data traceability. However, previous studies face challenges including single-dimensional indication and lack of dynamic trustworthy degree update mechanism. Therefore, this paper proposes a node trust evaluation and selection algorithm based on improved fuzzy Petri network (IFPN). Firstly, the multi-dimensional node trust evaluation and selection framework for practical Byzantine fault tolerance (PBFT)-empowered electric measurement data sharing is constructed. On this basis, IFPN is proposed to dynamically evaluate measurement data node trust, and nodes participating in the PBFT consensus process are selected based on the Top-N algorithm. Further, the trustworthy degree of IFPN is dynamically updated based on the fuzzy deviation to improve the accuracy. Finally, the superiority of the proposed algorithm has been verified through simulation.

Purpose: The full damping treatments have been widely used in many fields for structural vibration and noise reduction. Compared to the partial damping treatments, the full damping treatments have not significantly enhanced the effect of vibration reductions. It is essential to find the optimal damping treatments in lightweight designs. Moreover, the solution methods should be beneficial to engineering applications. Method: In this work, a layerwise finite element (FE) model of plates with constrain layer damping (CLD) treatments is proposed, based on Kerwin’s hypothesis. The dynamic characteristics of CLD system are analyzed by the modal strain energy (MSE) method. Based on the variable density method and the rational approximation of material properties (RAMP) interpolation scheme, a topology optimization model of the CLD system is built, and the optimal layouts are determined by the proposed modified guide-weight (MGW) method. The results are compared with optimal layouts using other common methods. Results: The layerwise FE model, the topology optimization model and the MGW method are validated by numerical examples. The proposed layerwise FEM-MSE solutions converge to the analytical or semi-analytical solutions more accurately than the NASTRAN/MSE solutions. The optimization results indicate that the added weight of viscoelastic material (VEM) layer decreases by 50 percent, and meanwhile the modal loss factors can just decrease by 5.18 percent compared to plates with VEM full coverage in some cases. Conclusion: The results of this work are beneficial to the vibration and sound radiation suppression of plates with CLD treatments in engineering applications.