"Daejeon is U" means that "citizens" are the core value of Daejeon
In other words, "Daejeon is you." In addition, "U" is not limited to only people, but also contains infinite possibilities and imaginative meanings that encompass the values of objects, places, nature, and culture that people have and should pursue in the future.
The "on" of the image conveys the meaning of "switch on". Familiarity is emphasized by the smile and shape. By using lower case letters, the slogan expresses a bright and friendly image.
The blue and green of the slogan are based on the colors of the Daejeon logo and draw on the connection with the CI: blue, for a city that aims to become a high-tech science center, and green, for an eco-friendly community.