在大多数情况下，例如在设计阶段，安装尚未完成。在这种情况下，设计人员将不得不考虑联结和不联结保护等电位的情况。谨慎的选择是在第一次固定阶段安装保护联结导体，因为在后期安装可能会更加困难和昂贵。它还可能涉及对建筑结构的损坏或需要明装，这对大多数客户来说 ...

Modern life makes us tired, right? But research from societies in Africa and South America suggests people in the ancient ...

Scientists researching Alpine glaciers store ice in Antarctica. By analysing air bubbles in the ice they may be able to predict the future ...