This study suggested comprehensive structural characterization methods for the commercial blue light emitting diodes(LEDs). By using the Z-contrast intensity profile of Cs-corrected high-angle annular dark field scanning transmission electron microscope(HAADF-STEM) images from a commercial lateral GaN-based blue light emitting diode, we obtained important structural information on the epilayer structure of the LED, which would have beendifficult to obtain by conventional analysis. This method was simple but very powerful to obtain structural and chemical information on epi-structures in a nanometer-scale resolution. One of the examples was that we could determine whether the barrier in the multi-quantum well(MQW) was GaN or InGaN. Plan-view TEM observations were performed from the commercial blue LED to characterize the threading dislocations(TDs) and the related V-pit defects. Each TD observed in the region with the total LED epilayer structure including the MQW showed V-pit defects for almost of TDs independent of the TD types: edge-, screw-, mixed TDs. The total TD density from the region with the total LED epilayer structure including the MQW was about 3.6 × 108 cm−2 with a relative ratio of Edge- : Screw- :Mixed-TD portion as 80%: 7%: 13%. However, in the mesa etched region without the MQW total TD density was about 2.5 × 108 cm−2 with a relative ratio of Edge- : Screw- :Mixed TD portion of 86%: 5%: 9 %. The higher TD density in the total LED epilayer structure implied new generation of TDs mostly from the MQW region.

A new Gentiana spp. cultivar ‘Skyhope’ was bred by crossing between ‘Jinbu-4 line’ with violet blue (VB 95B) colored petals and ‘Jinbu-1 line’ with violet blue (VB 93B) petals in 2000 year. The superior line of ‘0013-9’ was selected in Daegwallyeong from 2001 to 2003 year, and growth and flower characterization were conducted from 2004 to 2007 year in field of Daegwallyeong and Jinbu of Pyeongchang, Gangwon-do, Namwon, Jeollabuk-do and Jeju Special Self-Governing-do. The flower showed violet blue (VB 96A) color at opening, the petal of flower have not spot and flower stem color was purple. Flowers was opening at the same time from bottom to upside. Plant height was 68.1 cm, and number of flower stems per plant was 5.3 ea., number of flower node per stem is 5.9 ea., and Number of flowers per stem was 32.2 ea.. The flowering of ‘Skyhope’ cultivar was bloomed from the middle of July in Daegwallyeong and the later of July in Jinbu, Pyeongchang, Kangwon-do and the early of July in Namwon, Jeollabuk-do and the later of July in Jeju Special Self-Governing-do. ‘Skyhope’ cultivar can be used for cut flower.