1. School of Electrical and Computer Engineering, University of Seoul, Seoul 02504, South Korea
2. Department of Electrical and Computer Engineering, University of Texas at Austin, 10100 Burnet Road, 78758 Austin, TX, USA
3. Intel Corporation, 2501 NE Century Road, 97124 Hillsboro, OR, USA
4. Semiconductor Research and Development Center, Samsung Electronics, Hwaseong-si 18448, South Korea
5. Department of Computer Science and Engineering, Incheon National University, Incheon 22012, South Korea