**5.2 The essential of the batches of training set and test set**

Although the PVC process last just several hours (3*h*~8*h*), the sampling frequency is comparatively higher because it is necessary to online monitor time-variant batch process. The sampling interval is 5 seconds, so that all the measurements of any one batch is on the scope of (2000, 6000) due to the adjustment of the duration for different requirements of products. After more observation of the production, most of the durations of batches are around 3200 measurements and the distribution of the batches does not follow normal distribution.

Fig. 8. The profile of asynchronous batches of temperature of the reactor of PVC


Table 2. The situations of 10 tested batches of PVC

The data of 50 normal batches are selected from the examples of the practical process as a training dataset. There are other 50 batches sent to the history library Ω, so the number of the batches in Ω is 100.

From Fig.8 we can observe clearly the asynchronous chosen batches from temperature of the reactor (variable 1). There are 10 batches (#1~#10) taken as test data from the batch process in the plant. Some problems of these batches are listed in Table 2 in the polymerization of batch process, one tries to discriminate the abnormal of them with two statistics of SPE and T2 of MPCA, or SPE and I2 of MICA, and then find whose variables were affected.

254 Principal Component Analysis

Although the PVC process last just several hours (3*h*~8*h*), the sampling frequency is comparatively higher because it is necessary to online monitor time-variant batch process. The sampling interval is 5 seconds, so that all the measurements of any one batch is on the scope of (2000, 6000) due to the adjustment of the duration for different requirements of products. After more observation of the production, most of the durations of batches are around 3200 measurements and the distribution of the batches does not follow normal

> The all trajectories of temperature of rector in 50 batches

0 1000 2000 3000 4000 5000 6000

Sample number
