I spend time to know about a PHC system [13] [26]

−0.179

0.074

−0.004

−0.018

0.574

−0.115

0.034

I realize that using a PHC system creates many advantages [36] [49]

−0.031

0.015

0.025

0.088

0.733

0.077

−0.010

It makes sense to use a PHC system [36]

0.224

−0.073

−0.098

0.079

0.674

0.045

0.075