In recent years, elevator accident happens time by time. there are two main factors for this situation: 1. the lack of regular maintenance, 2,people know less about the principle of elevator construction......

Charging facilities mainly includes centralized charging station and distributed changing piles, scattered location and large number. In order to ensure user experience and operation efficiency, it is necessary to provide......

Along with the internet developing, live video has gradually become the mainstream expression of the Internet due to the integration of images, text, sound and other rich elements. 4G/5G multi sim cards technology plays a very important......

​​​​​​​In the era of rapid economic development, marketing and promotion are becoming increasingly hot, and outdoor advertising is increasing. However, the traditinoal management  is chaotic and low efficiency , lacks of scientific characteristics......