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Mobile phone signals shielding device is mainly for domestic college entrance examination, adult the university entrance exam, self-study exam and all kinds of colleges and universities in the process of examination, some students use mobile phone to cheat the status quo, and at the same time combined with all kinds of intermediate and senior high school students use mobile phones in the present situation of the class time loose hair message, as well as government agencies, enterprises of…Continue
air traffic control, but also may cause more serious consequences.
Drone "black flights" are not uncommon, and the results are shocking. According to foreign media reports, the German air traffic control center said that in 2018, there were nearly 200 incidents of drone "black flights" interfering with flights in the country, and the statistics are all from the naked eye of pilots because airport radar cannot detect small drones.…Continue
Unmanned aerial vehicles, or uavs, are unmanned aircraft operated by radio remote control devices and autonomous programmed controls. Uav technology originated in the early 20th century. In the 1900s before the outbreak of world war I, some balloon bombs and target aircraft were developed. In the 1910s, the beginning of the first world war provided opportunities for the development of uav technology. Britain, the United States and other countries began the research and development of uav…Continue