[clarification needed] The Gangbyeon branch, located in Gwangjin District, contains an estimated 2000 electronics and appliances stores.
[2] On 5 July 2011, the top 19 stories of the 39-story building housing the Gangbyeon branch of Techno Mart shook violently for 10 minutes and was evacuated for two days.
[3] After study, it was determined that 17 people performing Tae Bo exercises to "The Power" in a 12th floor fitness center caused the building to vibrate by creating a mechanical resonance.
The tentative conclusion was the consensus among the six professors from an architectural institute and vibration measurement experts who participated in a recreation of the event.
The Architectural Institute of Korea was scheduled to release the final results of the safety inspection later in 2011.