First working place was the Research center of SindoRicoh which is the joint-vanture of Sindo Enterprise and Ricoh company. Career as embedded a software engineer started there. I was a research engineer on the team that developed commercialized embedded Linux laser printer platform.

After three and half years of SindoRicoh, I joined the Software Laboratories, Chief Technology Operations of the Samsung Electronics that is the largest software research lab in Korea.
In Samsung Electronics, I focused on researching Operating System level low power technology for main processors of digital TVs and mobile phones. From 2005, new file system research was started on NAND flash and hard disk drives for consumer products. The results of the research were presented at the Linux Symposium 2006.
Other study was on creating a new journaling method to protect saved user contents through file system on multimedia consumer electronics (CE), and a new protection method for metadata of file system even when bad sectors occur on HDD.

As of 2006, I became the member of virtualization group, which introduced XenARM. I represented Samsung Electronics as the member of Architecture Group at Consumer Electronics Linux Forum from 2004 to 2006.