Acknowledgment. This research was supported by the MSIP (Ministry of
Science, ICT and Future Planning), Korea, under the CITRC (Convergence
Information Technology Research Center) support program (NIPA-2013-H0401-13-
2011) supervised by the NIPA (National IT Industry Promotion Agency) and this
research was financially supported by the Ministry of Education (MOE) and National
Research Foundation of Korea (NRF) through the Human Resource Training Project
for Regional Innovation (No. 2014H1C1A1066414)