발표 자료 https://docs.google.com/presentation/d/e/2PACX-1vT0_Vm1WbJjqOUx0hfmwa7emjvu1XtpqDGJeKj1WKwkbjj4yaYZxfUsgVTjsuEZJw/pub?start=true&loop=false&delayms=15000