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正改應(yīng)變或線應(yīng)變由每單位長度內(nèi)的長度改變量來定義.Normal or linear strain is defined as the change in length per unit length.圓盤外有透明的防護罩,以免偶然在圓盤上弄上污點或線跡.A transparent cover is provided to protect the disc against accidental marking or smudging.小系...