W. ALAN DAVIS is a professor in the department of electrical engineering at the University of Texas at Arlington. He was previously employed at Raytheon, where he worked on IMPATT diode power combiners, thermal response of IMPATT diodes, broadband directional couplers, Schiffman phase shifters, and filter design. He was also involved in computer optimization techniques and in software design for automated test stations. More recently, Davis has worked on nonlinear parametric effects and self-heating effects of silicon on insulator transistors.