To determine the actual level of bl

To determine the actual level of blockage in each experiment, the experts defined the reasoning that considers different combinations of damage conditions that are observed on building components (Table 4). This reasoning was used to determine the ground truth, which was used to (1) evaluate the accuracyofthe sensor data, (2) evaluate the accuracy of the video camera data, and (3) create decision trees. When evaluating the accuracy of sensor data, the ground truth
was determined via visually evaluating the real damage that occurred on each building component during the experiments. On the other hand, the actual blockage levels at each node were determined to be used as ground truth for evaluation of accuracy of the video camera and for creating decision trees. The reasoning created by expert opinion (Table 4) was used when determining the related blockage levels caused by damage on each building component. For instance, when two crosswise connections of the suspended ceiling are detached, the resulting blockage is a low-level blockage that does not prevent the passage from the hallway; therefore, it is classified as level B blockage. When two or more building components in the same node got damaged at the same time, die blockage level that was caused by each individual element is determined by using Table 4, and the highest blockage level was selected as the final blockage level. For instance, when two adjacent corners of the suspended ceiling were detached (i.e., causing a blockage level D), and a bookshelf fell down (i.e., blockage level C),
the worst case was considered and the blockage level D was assigned.
For interpreting the video camera data, the snapshots taken during the experiments were evaluated. The snapshots were visually examined, and the blockage ratio intervals (e,g„ 21%-40%) that correspond to each blockage level (i.e., A, B, C, D and E) were determined. Table 5
shows the intervals of blockage ratios that was calculated from video camera snapshots and the corresponding blockage levels assigned.