Fig. 10From: Unsupervised learning approach to automation of hammering test using topological informationSchematic of the test block used for the void detection experiment: a polystyrene block of \(200 \times 200 \times 30\) mm was placed at a depth of 30 mm in order to simulate a void type defect given the impossibility to induce a controlled volume of air inside a concrete block. (Dimensions specified in mm)Back to article page