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The 1100 kV composite bushing is one of the most important components in the ultra-high voltage electrical network. Therefore, the safety and integrity must be ensured during the operation under any conditions such as an earthquake. The primary object of this paper is to investigate the effects of oil in the dome on the dynamic responses of the 1100 kV composite bushing when subjected to horizontal seismic ground motion. The coupled finite element method (FEM) and smoothed particle hydrodynamics (SPH) method is adopted to simulate the fluid structure interaction (FSI) between the oil and the dome. The influences of particle’s distributions on the numerical results and computational efficiencies are discussed. For comparison with the coupled FEM/SPH method, the additional mass model is also performed. The influences of oil oscillation on the time history of absolute acceleration of 1100 kV composite bushing are discussed, as well as the relative displacement and the bending moment at the base of the structure. The results show that the motion of oil in the dome with free surface can limit the vibration of the 1100 kV composite bushing and can efficiently dissipate the kinetic energy of the 1100 kV composite bushing by fluid-structure interaction.

As an important method for solving boundary value problems of differential equations, the finite element method (FEM) has been widely used in the fields of engineering and academic research. For two dimensional problems, the traditional finite element method mainly adopts triangular and quadrilateral elements, but the triangular element is constant strain element, its accuracy is low, the poor adaptability of quadrilateral element with complex geometry. The polygon element is more flexible and convenient in the discrete complex geometric model. Some interpolation functions of the polygon element were introduced. And some analysis was given. The numerical calculation accuracy and related features of different interpolation function were studied. The damage analysis for the koyna dam was given by using the polygonal element polygonal element of Wachspress interpolation function. The damage result is very similar to that by using Xfem, which shows the calculation accuracy of this method is very high.

Summary: This study was aimed to evaluate the effects of pre‐slaughter low‐current/high‐frequency (LH) electrical stunning (ES) on lipid oxidative stability, antioxidant enzyme activity and gene expression of mitogen‐activated protein kinase/nuclear factor erythroid 2‐related factor 2 (MAPK/Nrf2) signalling pathway in thigh muscle of broilers. Eighteen birds were randomly allocated to the following three treatments with six replicates per treatment and one bird per replicate: without stunning (control); water‐bath ES with sinusoidal alternating LH (86 mA, 1000 Hz, LHES) or high current/low frequency (HL) (130 mA, 60 Hz, HLES). Stunning methods did not affect malondialdehyde level (d 0 ~ d 9) or antioxidant enzymes' activity at d 0 ~ d 2. LHES enhanced glutathione S‐transferase activity at d 3 and gene expression of MAPKs and Nrf2 compared with HLES. In conclusion, LHES enhanced gene expression of MAPK/Nrf2 pathway, whereas had no superiority over HLES in lipid oxidative stability (4 °C, 9 days) of thigh muscle in broilers. [ABSTRACT FROM AUTHOR]