Sensing Skin Detects Invisible Cracks in Building Structures (image) North Carolina State University Share Print E-Mail Caption The multi-functional, multi-layer sensing skin is applied to a polymeric substrate with a physical crack and a reservoir for exposing the sensing skin to aggressive ions. Credit Julie Williams Dixon Usage Restrictions Photo credit must be given. Share Print E-Mail Disclaimer: AAAS and EurekAlert! are not responsible for the accuracy of news releases posted to EurekAlert! by contributing institutions or for the use of any information through the EurekAlert system.