Over on the R&B/Hip-Hop Songs chart, Rihanna’s “Diamonds” continues to sparkle in the No. 1 slot for a second week, while Kanye West’s “Clique” (with Jay-Z and Big Sean) stands firm at ...

The rapid development and widespread application of UAVs have, to some extent, accelerated the utilization of low-altitude airspace resources. According to statistics from the Civil Aviation ...