Power System Transients Analysis by Wavelet Transforms

In contrast to Fourier transform,wavelet transform is especially suitable for transient analysis because of its time-frequency characteristics with automatically-adjusted window lengths.Research shows that wavelet transform is one of the most powerful tools for power system transient analysis.The basic ideas of wavelet transform are presented in the paper together with several power system applications,It is clear that wavelet transform has some clear advantages over other transforms in detecting.analyzing,and identifying various types of power system transients.     

透空式半圆体高精度全天候安装施工关键技术

透空式半圆体作为一种新型结构首次在上海市海洋生态修复项目中应用,其具有抗倾性好,地基承载力小,施工进度快,造价低等诸多优点。在此主要介绍上海临港滨海海洋生态保护修复项目（二标）约4 200个透空式半圆体的安装施工关键技术,根据现场施工情况和透空式半圆体结构特点,采用起重船水上半圆体安装工艺,并在水上定位工艺、透空式半圆体夹具设计、吊点设计等方面进行了多项创新。新工艺、新技术高效的实现了安全、优质的预期目标,解决了临港海洋生态保护修复项目牡蛎礁体透空式半圆体弧线段安装中遇到的问题,为类似工程提供一定的参考依据。