• Vibration of Periodic Drill-Strings with Local Sources of Resonance 

      Akl, Wael; Alsupie, Hajid; Sassi, Sadok; Baz, Amr M. ( Multidisciplinary Digital Publishing Institute (MDPI) , 2021 , Article)
      A new class of drill-strings is proposed for attenuating undesirable vibrations to ensure effective operation. The drill-string is provided with passive periodic inserts, which are integrated with sources of local resonance ...