**About the Editors**

**Salvatore Graziani**received his M.S. in electronic engineering and Ph.D. in electrical engineering from the Universita degli Studi di Catania, Italy, in 1990 and 1994, respectively. Since 1990, he has been ` with the Dipartimento di Ingegneria Elettrica, Elettronica e Informatica, Universita di Catania, where ` he is an Associate Professor of electric and electronic measurement and instrumentation. His primary research interests lie in the field of sensors and actuators, as well as soft sensors. He has coauthored several scientific papers and books.

**Maria Gabriella Xibilia** received her M.S. degree in electronic engineering and Ph.D. in electrical engineering from the Universita degli Studi di Catania, Catania, Italy, in 1991 and 1995, respectively. ` Since 1998, she has been with the Dipartimento di Ingegneria, Universita di Messina, Messina, Italy, ` where she is currently an Associate Professor of automatic control. She has coauthored several scientific papers and books.

Her current research interests include system identification, soft sensors, process control, nonlinear systems, and machine learning.
