Structural Health Monitoring Using Smart Sensors - ideals ...

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Normalized accumulated stress
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Normalized accumulated stress
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Figure 8.20. Damage detection (damaged element: Element 21): (a) mass perturbation
DLV; and (b) SDLV.
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Normalized accumulated stress
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Figure 8.21. Damage detection (damaged element: Element 22): (a) mass perturbation
DLV; and (b) SDLV.
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false-positives. The cells corresponding to false-negatives are shaded to distinguish falsenegatives
from false-positives. The number of false damage detection using the mass
perturbation DLV method is, overall, larger than the number for the SDLV method,
though the sample size is small.
Tables 8.4 to 8.7 also suggest a way for robust damage detection. The summary of
damage detection using the SDLV method in Tables 8.6 and 8.7 shows that the percentage
of false damage detection cases is always smaller than or equal to 33 percent, while the
percentage for the mass perturbation DLV method can be larger than 50 percent. From this
observation, reliable damage localization might be possible by repeating damage detection
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