Submillimeter-HCN diagram proposed by Izumi et al. (2016) for the high-resolution observations (spatial resolution < 500 pc) using the line intensity ratios R_HCN/HCO⁺ and R_HCN/CS. Red circles represent the AGNs and the blue squares indicate the SB galaxies. We include the line ratios of NGC 1808 (diamonds) measured in the central spiral, called here as “AGN” and in a clump detected ∼150 pc north-west of central position in all the dense tracers.