题干

在下面一段文字横线处补写恰当的语句,使整段文字语意完整连贯,内容贴切,逻辑严密。每处不超过15个字。

    对失去联系的马来西亚航空公司370航班的搜索,引起了公众对有关如何追踪飞机的诸多疑问,追踪飞机方位的一个重要手段就是借助雷达。①____?雷达天线把接收到的波立刻反射送往特殊的接收设备迅速进行处理,通过处理结果,就能知道有关目标物体的部分信息。但是,专家认为:②____。如果飞机飞行的高度足够低的话,雷达发射的天线射束很难照射到飞机,就会处于雷达的“盲区”内。此外,专家还监测到:③____。比如雷达进行远距离探测时发射和接收信号耗费的电量较大;雷达发射的信号在大气中穿行时会不断减弱,遇到雨天时更严重。

上一题 下一题 0.0难度 选择题 更新时间:2018-04-26 11:04:05

答案(点此获取答案解析)

雷达是怎么做到这些的,雷达有低空盲区的特点,雷达探测还受距离和天气的影响

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    Most of us have been in this situation: You're on your way to your friend's house, then you suddenly ask yourself,"Did I remember to turn the lights off?” For those with "smart homes", however, this wouldn't be a problem.

Over the last few years,smart home technology has become more popular. Thanks to user-friendly products like intelligent lighting and heating controllers, people can control nearly every electrical item in their homes from anywhere in the world.

    While smart homes aren't new, companies like Philips, Amazon and Xiaomi have finally brought automation to everyday people with affordable products like artificial intelligence(AI) speakers and sensors.

    “The obvious message is that you can stop wasting energy,” Tom Kerber, director of research for U. S -based digital company Parks Associates, told The Guardian.

    And the technology also has more meaningful uses. In Norway, for example, one company is using smart tech to make life easier for its elderly customers. Abilia's system allows carers to check up on patients through a tablet on a wall inside their home. The device sends patients reminders about tasks, such as when they need to take medication(冥想). It can even tell carers if there's any unusual activity in the home that could be life-threatening.

    “This kind of system allows people to take care of themselves, which is the most important thing,” Abilia's vice president, Oystein Johnsen, told the BBC. "It also saves the government money. In Norway, it costs 1 million kroner(about 0. 8 million yuan )per year to have someone in a care home. This system costs 15,000 kroner a year.”

    So, for those who have already "gone smart", will it ever be possible to go back to do things in the old-fashioned way? "I think it would be difficult. When we go to a friend's house or on vacation we find ourselves expecting the house to do things for us that we should do, "Poulson, 35, a senior program manager from Seattle.,U. S.,explained.