1. Ming Hsieh Department of Electrical and Computer Engineering University of Southern California Los Angeles CA 90089 USA
2. Center for Power Electronics Systems Bradley Department of Electrical and Computer Engineering Virginia Polytechnic Institute and State University Blacksburg VA 24060 USA
3. Mork Family Department of Chemical Engineering and Materials Science University of Southern California Los Angeles CA 90089 USA
4. Department of Electrical and Computer Engineering Carnegie Mellon University Pittsburgh PA 15213 USA