https://patents.justia.com/patent/20180210565

๋น„์Šทํ•œ ๋ชจ๋“ˆํ˜• ์„ผ์„œ์˜ ๊ด€ํ•œ ํŠนํ—ˆ์ธ๋Œ€ ์ด๊ฒŒ ํฌ๋‹ˆ์ง€๊บผ๋Š” ์•„๋‹Œ๊ฑฐ๊ฐ™์€๋Œ€

๋“ค์–ด๋ณด๋‹ˆ๊นŒ ๋งˆ๊ทธ๋„ค์Š˜ ๋งˆ์šฐ์Šค์— ๊ด€ํ•œ ํŠนํ—ˆ๋ฅผ ๋˜ ํŒŒ์ด๋„ ๋งˆ์šฐ์Šค๊ฐ€ ๊ฐ€์ง€๊ณ  ์žˆ๋‹ค๋„ค ใ…‹ใ…‹ใ…‹ใ…‹