Big Brain, is a South-Korean R&B ballad group that consist of four-members under the label World Show Market. They have been active since 2010 and debuted on October 22, 2015 with the album Billionaire Sound and their breakthrough song “Welcome”, they were group of students who decided to form their own group. During pre-debut, they were known as The Man, but changed their name due to similarity with another senior group. Big Brain is a group that enjoys music and hopes that their music will heal others. Before their official debut, many people recognised their outstanding talent, calling them the next Brown Eyed Soul and compared them to Big Mama Before they held their official debut concert in South Korea, they were busking around New York City and performed in several places including Times Square, Central Park, other places in Manhattan; the group debuted on October 22, 2015 with the release of their first mini-album Billionare Sound and their digital single featuring title track "Welcome".

"Welcome" is an emotional ballad mixed with a fresh tempo. The story of the song is about an honest man who wishes that his ex-lover would never have a beautiful relationship with another man, they showed an impressive work. They became an opening act in Olivia Newton-John concert on May, 14 Sanghoon Jinyong Byeongeun Honghyun

A T-square is a technical drawing instrument used by draftsmen as a guide for drawing horizontal lines on a drafting table. It may guide a set square to draw vertical or diagonal lines, its name comes from its resemblance to the letter T. T-squares come in varying sizes, common lengths being 18 inches, 24 inches, 30 inches, 36 inches and 42 inches. T-squares are used to measure and cut drywall. Drywall T-squares are made of aluminium and have a 48-inch long tongue. Higher-end table saws are equipped with T-square fences; these table saw fences are attached to a rail only on the front side of the table unlike traditional fences which clamp to both the front and the rear of the table. A T-square has two components—the long shaft called the "blade" and the short shaft called the "stock" or "head"; the T-square has a transparent edge made of plastic which should be free of nicks and cracks in order to provide smooth, straight lines. Technical drawing tools