The lightweight design and miniaturization of metallic dampers have broad application prospects in seismic engineering. In this study, the superplastic property and the maximum energy dissipation capacity per unit mass of low-yield-strength steel (LYS) are investigated via comparison with those of several common metallic damping materials by tests. Additionally, the boundary constraints of an LYS shear panel damper are studied further. Our experimental results suggest that LYS is an excellent damping material for achieving the lightweight design goal. A novel design of a lightweight damper, having excellent deformation ability and robust mechanical properties, is presented. The findings of this study are expected to be useful in understanding the lightweight design of dampers.

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Microgrid is a power system that includes various energy sources (e.g., solar panels and wind turbines), where a number of device status and sensing data are collected and transmitted by smart sensors. Based on sensing-as-a-service in microgrid, sensor owners and sensor data consumers can effectively perform data sharing operations. However, the state-of-the-art sensor data sharing works in microgrid have the following two limitations: (i) cannot support fine-grained authorization for sensor owners and sensor data consumers and (ii) fail to simultaneously consider confidentiality and authenticity for sensor data sharing. To address the problems, in this article, we propose a lightweight privacy-preserving sensing data sharing system with fine-grained authorization in microgrid. Technically, we employed attribute-based signature methodology to design a fined-grained authorization mechanism for sensor data users. Moreover, a lightweight hyper elliptic curve-based signcryption scheme is employed to provide confidentiality and authenticity for sensor data sharing. To clarify the feasibility of our proposed system, we implement the system and evaluate the performance. The experimental results show that the system achieves small communication and time overhead, as well as highly acceptable gas consumption of smart contract.

This paper presents a new principle and method of kinematics to analyze the singularity of Stewart-Gough parallel manipulators and addresses the property identification of the position-singularity loci of 6-3 Stewart-Gough manipulators for some special orientations. Based on the kinematics relationship of a rigid body, a necessary and sufficient condition that three velocities of three non-collinear points in a moving rigid body can determine a screw motion is addressed in this paper. With the above-mentioned condition, a symbolic analytical polynomial expression of three degree in the moving platform position parameters is derived, which represents the position-singularity locus of the 6-3 Stewart-Gough parallel manipulators for some special orientations, and property identification of the position -singularity loci of the 6-3 Stewart-Gough parallel manipulator for these special orientations are studied in detail as well. It is shown that position-singularity loci of the 6-3 Stewart-Gough parallel manipulator for these special orientations will be a plane and hyperholic paraboloid, even three intersecting planes.