Abstract: Disclosed are novel compounds of Chemical Formula 1, optical isomers of the compounds, and pharmaceutically acceptable salts of the compounds or the optical isomers. The compounds, isomers, and salts exhibit excellent activity as GLP-1 receptor agonists. In particular, they, as GLP-1 receptor agonists, exhibit excellent glucose tolerance, thus having a great potential to be used as therapeutic agents for metabolic diseases. Moreover, they exhibit excellent pharmacological safety for cardiovascular systems.

Abstract: Provided is a ceiling storage system capable of correcting a working position and constantly checking stability of a structure by detecting an amount of change in a facility. According to the ceiling storage system, a transport vehicle moves to an upper portion of a first storage area of a plurality of storage areas in a state of gripping an article, and the transport vehicle measures a first distance value between the transport vehicle and the first storage area using a distance sensor and measures a relative position value between the transport vehicle and the first storage area using a vision sensor, before unloading the article from the first storage area.

Abstract: The present invention relates to a laser disk player having a karaoke capability, and more particularly to a laser disk player karaoke apparatus that compares the tempo of a musical selection reproduced from a laser disk with the tempo at which a user is singing, in order to permit evaluation of singing ability. When the singer's tempo does not correspond with the tempo of the music, the apparatus can match the music's tempo reproduced from the laser disk to the user's singing tempo. Particularly, if an aural synchronizing signal is recorded on the laser disk to indicate where singing of a song should start, a time difference is obtained during playback, indicating the time between the aural synchronizing signal and an aural signal input by a user via an external microphone. The time difference is used to correct the playback tempo and to assess the user's singing ability.