Stealth plane: It is by studying bionics and applying the latest technology and materials that people finally realize invisibility on a huge plane. The purpose of stealth aircraft is to make it impossible for radar to detect the existence of aircraft. Stealth aircraft can minimize or eliminate the useful signals received by radar at this stage. Although it is one of the most confidential military secrets, stealth technology has attracted great attention all over the world.
Phonetic (pinyin: yǐn, y n) is a first-class standardized Chinese character (commonly used word). The oldest form of this word is the Warring States script. The original meaning of "concealment" is to build a wall to cover up, and the extension refers to hiding and covering up. It also means hiding from others. Further extension refers to hiding. It also extends to hidden things. For example, "secrets that can't be told" and "hiding" also mean pity and sympathy.
In ancient times, most wise men were either stupid or fake, and finally they could not retreat to the mountains or hide in the streets. Seeing these scrawny children, everyone was moved with compassion, giving generously and helping out. Xiao Li went to the south in order not to get into trouble. If the road is not good, hide it. Don't blame me for being silent and not talking about state affairs.