皮皮学,免费搜题
登录
搜题
【简答题】
Black Box You never see them, but they're with you every time you fly. They record where you're going,how fast you're traveling and whether everything on your airplane is functioning normally. Their ability to resist almost any disaster makes them seem like something out of a comic (漫画)  book.They're known as the black box. When planes fall from the sky, as a Yemeni airliner did on its way to the Comoros Islands in the Indian Ocean on June 30, 2009, the black box is the best method for identifying what went wrong. So when a French submarine(潜水艇)  discovered its homing signal five days later, it marked a huge step toward determining the cause of the disaster in which 152 passengers were killed. In 1958. Australian scientist David Warren developed a flight-memory recorder that would track basic information like altitude and direction. That was the first model for a black box, which became a requirement on all US commercial flights by 1960. Early models often failed to resist crashes, however, so in 1965 it was completely redesigned. That same year, the Federal Aviation Authority required that the boxes, which were never actually black, be painted orange or yellow to be easier to see. Modem airplanes have two black boxes: a voice recorder, which tracks pilots' conversations, and a flight-data recorder, which monitors fuel levels, engine noises and other operating functions that help experts reconstruct the aircraft's final moments. The boxes can resist powerful force and temperatures up t0 2,OOOoF. They're also able to send out signals from depths of 20,000 ft. Experts believe the boxes from Air France Flight 447 ,  which crashed near Brazil on June 1 , 2009 ,  are in water nearly that deep, but statistics say they're still likely to turn up. In the approximately 20 deep-sea crashes over the past 30 years, only one plane's black boxes were never recovered. 小题1:What can we leam about the black box from the passage? A.It helps an airplane function normally. B.Its ability to avoid disasters is amazing. C.It is necessary equipment on an airplane. D.The idea for its design comes from a comic book. 小题2:From the black box on the Yemeni airliner we can get information about _____. A.the scene of the crash and the damage B.data for analyzing the cause of the crash C.the total number of passengers on board D.homing signals sent by the pilot before the crash 小题3:The Federal Aviation Authority required the black boxes be painted orange or yellow to A.make them easily identified B.meet the international standards C.caution people to handle them with care D.distinguish them from the color of the plane 小题4:What do we know about the black boxes from Air France Flight 447? A.They have stopped sending homing signals. B.They were destroyed somewhere near Brazil. C.There is an urgent need for them to be restructured. D.There is still a good chance of their being recovered.
拍照语音搜题,微信中搜索"皮皮学"使用
参考答案:
参考解析:
知识点:
.
..
皮皮学刷刷变学霸
举一反三
【多选题】盘点作业 应做到( )
A.
初点作业
B.
复点作业
C.
抽点作业
D.
店员的盘点作业检查
E.
店长的盘点作业检查
【多选题】蚕丝织物适合制作
A.
运动服
B.
工作服
C.
礼服
D.
旗袍
【单选题】在盘点作业中,盘点依据是盘存单和盘点依据是终端显示的货品信息,它们对应的盘点作业分别是( )。
A.
表单盘点、表单盘点
B.
表单盘点、RF盘点
C.
RF盘点、表单盘点
D.
RF盘点、RF盘点
【单选题】天线增益与天线的()密切相关
A.
功率
B.
能量
C.
方向图
D.
主瓣
【简答题】条据作业.doc
【单选题】对于天线增益说法错误的是()?
A.
天线增益的值等于,相同输入功率时,天线在某一规定方向上的辐射功率密度与参考天线(通常采用理想辐射点源)辐射功率密度的比值。.
B.
增益与天线方向图密切相关,方向图主瓣越窄,副瓣越小,增益越高。
C.
无论什么场景下,天线的增益都是越大越好,
D.
参考基准为全方向性天线,天线增益单位为dBi
【单选题】下列地址中,属于CIDR地址块86.32.0.0/12中的地址是
A.
86.33.224.123
B.
86.79.65.126
C.
86.79.65.216
D.
86.68.206.154
【判断题】采购计划与预算的编订
A.
正确
B.
错误
【判断题】盘点作业方法主要有两种:表单盘点和RF盘点。( )
A.
正确
B.
错误
【多选题】盘点作业应做到()
A.
初点作业
B.
复点作业
C.
抽查作业
D.
店员的盘点作业检查
E.
店长的盘点作业检查
相关题目: