I worked primarily with acoustics and noise control, with my emphasis being in active noise and vibration control. I worked with the aircraft fuselage and all of the vibrations and noises created in there and limiting their effects on the cockpit. Of course, automobile engines are also very noisy being so close to the driver. I also worked with compressors. I worked with really small compressors to really big compressors. I worked on small refrigeration units using passive and active control techniques. You�d be surprised at how big an issue refrigerator noise is overseas, in Europe and Asia with their tight living conditions. I also worked with huge engine compressors of up to sixty horsepower. That�s really big for a university, you know. I also worked with reciprocating compressors, screw compressors, scroll compressors, and rotary compressors.