2019年4月7日
UPC10880 LED
摘要： 题目描述 A Light-Emitting Diode (LED) is a semiconductor light source, which emits light when an electric current of voltage higher than a threshhold is a 阅读全文
posted @ 2019-04-07 17:04 Albert_liu 阅读(241) 评论(0) 推荐(0) 编辑