In 1989 he finished his PhD studies in surveying. In 1997-1998 and 1999 was the secretary of the organising committee of the main Italian congress for Surveying, photogrammetry, Geomatics, GIS, remote sensing (ASITA). In 1999 and 1998 Vassena has organised two scientific expeditions to Changri Nup glacier (close to Mountain Everest) to study the glaciers deformations using GPS. In these researches RTK technology with radio-modem as radio-repeater was used. He has also worked on static monitoring of buildings: in particular he worked on the deformation measurements and analysis of the Leaning Tower of Pisa, Olimpico Stadium in Rome, Meazza stadium in Milano and Delle Alpi Stadium in Torino. He studied and applied new system for the automatic monitoring of buildings (San Carlo Basilica in Rome, Battistero of Cremona). He studied and applied new technologies for the data transmission using optical fibres (Bell Tower of the Monza Cathedral). 1998-1999: he studied advanced application of GIS for the analysis and definition of the border of the municipalities of the Lombardia Region, using various cartographic maps (cadastral, 1:10000, 1:2000 maps). He has worked on 3D virtual reality vision of the historical square of the city of Monza (ITALY) and of the monastic area in Narga Selasse (Dek island on Tana lake - Etiopia). He studied several architectural surveys as the ones at the Palazzo d'Arco, Archivio di Stato (Mantova), Santa Maria in Solario (Santa Giulia museum) in Brescia, Palazzo Ceni a Medole (Mantua). In 2000 he was member of the staff that moved to the South Pole for GPS measurements on the front of glaciers.
