The present invention a method of improving, enhancing, or modifying a fragrance formulation through the addition of an olfactory acceptable amount of the following compound:wherein R represents a saturated C2-C4 alkyl straight chain or branched. Thereby, the variable valve actuator can adjust a lift time and a lift distance of each valve without changing positions of the drive cams and the camshaft, and more easily adjust the lift time of each valve, and have very excellent applicability to the engine due to simple internal configuration. A material having an expansion degree sufficient for application of pressure to the wellbore walls and for keeping at least one fracture open is used as the material which expands while hardening or setting. The method may also include presenting at least one of the predicted noise level and the predicted emissions level on a display to a pilot of the airplane to permit operation of the airplane to substantially minimize at least one of an actual noise level and an actual emissions level at each of the plurality of ground based noise and emissions monitoring stations. The system for controlling a heating and ventilating system includes an input for receiving a demand signal and a heater control circuitry for controlling the heat output of a heat source. The seal groove is preferably defined by a constant radius.