1 XL â or EXL, Exploration Licence (United Kingdom), a type of onshore licence issued between the First Onshore Licensing Round (1986) and the Sixth (1992). 2  Xln â Crystalline (minerals). 3  XLPE-Cross-linked Polyethylene. 4  XMAC â Cross-Multipole Array Acoustic log.
When the frequency approaches 120 CPM (2 Hz), occupants perceive the ride as harsh. Consequently, the suspension of the average family sedan will have a natural frequency of about 60 to 90 CPM. A high-performance sports car will have a stiffer suspension with a natural frequency of about 120 to 150 CPM (2 to 2.5 Hz). Originally, human sensitivity to ride frequency was believed to be associated with the natural oscillations of an adult human body during a walking gait.
9 Cars That Average 50 MPG or Better on the Highway: You'll Be Shocked By No. 1! These nine cars offer consumers the best fuel efficiency on the highway. Here's the shock: Tesla isn't No. 1. Mar 9, 2014 at 11:31AM. My nose would shoot to about six feet in length if I exclaimed that gas mileage was an important feature to me when purchasing a car. However, I'm very much in the minority on this one.