Issue 70

T. Pham-Bao et alii, Frattura ed Integrità Strutturale, 70 (2024) 55-70; DOI: 10.3221/IGF-ESIS.70.03

D ATA ANALYSIS AND RESULTS

Data analysis ig. 5 summarises the data processing procedures in this paper. The raw data collection part has been mentioned in the above section. Next, As shown in Fig. 4, the raw signal is converted into an RDT signal by formula (1). The duration of the subsegments is set to 5 seconds, and other parameters depend on each signal considered. The results for the signal of damage case D00 at sensor location S1 are shown in Fig. 6. F

Figure 5: The total diagram of the data processing process.

Figure 6: This figure illustrates the process of converting a raw signal into an RDT signal.

After converting raw data to random decrement data, we calculated the correlation between sensor locations according to the formula (17). We use correlation values as the features of this study.

n



, x k X X Y Y   , x k x )( x

(

)

i

i

j

j



k

1



r

(17)

x x

n

n

i j





2 ) . ( X X Y Y  

2

(

)

, x k

x

, x l

x

i

i

j

j





k

l

1

1

where x i is the signal at i th location (i = 1, 2, …, 7) x j is the signal at j th location (j = 1, 2, …, 7) X are the elements in the signal x i X is the mean value of the signal x i Y are the elements in the signal x j

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