appearance surface
7.The appearance and its evaluation of typical facture surface were analyzed by Drop-weight tear tests (DWTT) on thick wall X70 high-grade steel line pipe. Furthermore, the effects of wall thickness and test temperature on the appearance of facture surface were studied.
10.The shadow regions in aerial image provide lots of information about the appearance, relative position and surface feature of object, and they are the obvious evidences of objects higher than the surrounding background.

