1. Electrical Insulation Research Center, Institute of Materials Science, University of Connecticut, 97 N Eagleville Road, Storrs, Connecticut 06269, United States
2. School of Materials Science and Engineering, Georgia Institute of Technology, 771 Ferst Drive NW, Atlanta, Georgia 30332, United States
3. Department of Electrical and Computer Engineering, University of Connecticut, 371 Fairfield Way, Storrs, Connecticut 06269, United States