Abstract: The present invention relates to: a pyrene derivative compound having a specific structure; and a high efficiency organic light-emitting device employing the pyrene derivative compound in a light emitting layer and thus having excellent light-emitting characteristics. The organic light-emitting device according to the present invention can be configured as a high efficiency organic light-emitting device having excellent light-emitting characteristics by employing the pyrene derivative compound having the specific structure as a host in the light emitting layer, and thus can be usefully applied industrially in lighting devices, as well as various display devices such as flat, flexible, and wearable displays.

Abstract: An organic light-emitting device according to the present invention uses a pyrene derivative compound having a characteristic structure as a host in a light-emitting layer to realize a long-lifespan and high-efficiency organic light-emitting device having excellent light-emitting characteristics in terms of lifespan and luminescence efficiency. Accordingly, the organic light-emitting device can be usefully applied, in the industrial aspect, for various display devices such as flat panel, flexible, and wearable displays, as well as lighting devices.

Abstract: The present invention relates to a novel heterocyclic compound usable in an organic light-emitting device and to an organic light-emitting device comprising same, wherein [chemical formula A] is as described in the detailed description of the invention.

Abstract: A performance evaluation method for use in a karaoke apparatus evaluates a singing performance of a karaoke singer by measuring differences between the karaoke singer's vocal rendition and an accompanying music produced by an audiovisual device. Digitized voice signals and their corresponding digitized accompaniment signals are produced by sampling simultaneously the karaoke singer's vocal rendition and the accompanying music, respectively. Then, a difference between a digitized voice signal and its corresponding digitized accompaniment signal and a trend of differences are calculated and used to generate a performance score.