以Comment on one greatest invention or discovery in 21century 为要求的 大学水平英语作文 300字

以Comment on one greatest invention or discovery in 21century 为要求的 大学水平英语作文 300字
以Comment on one greatest invention or discovery in 21century 为要求的 大学水平英语作文 300字

以Comment on one greatest invention or discovery in 21century 为要求的 大学水平英语作文 300字
THE explosive eruption of Eyjafjallajokull,an Icelandic volcano,wreaked havoc on air travel over the North Atlantic for several weeks this spring.The very existence of the ash cloud thrown into the sky was bad enough.But an inability to predict the cloud’s behaviour made matters worse.In particular,sudden changes in its height made the job of flying safely above it a tricky one.
Now a team of researchers at the British and Icelandic Meteorological Offices,led by Alec Bennett,may have found a way round the problem of predicting the height of volcanic ash clouds like that created by Eyjafjallajokull.As they report in Environmental Research Letters,the lightning the ash generates tells all.
Volcanic-ash clouds contain a lot of static electricity.This is eventually discharged as bolts of lightning.The details,however,are obscure,so Dr Bennett and his colleagues decided to take advantage of ATDnet,a British long-range lightning-location network,to look at the phenomenon in more detail.
ATDnet is an arrangement of 11 sensors scattered across Eurasia,one of which is in Iceland.It is designed to detect the low-frequency radio pulses emitted by lightning strikes.Such pulses can travel thousands of kilometres,which means they are frequently picked up by more than one of ATDnet’s sensors.When that happens,triangulation allows the system to locate the original bolt with precision.Using ATDnet,Dr Bennett and his colleagues were able to identify 790 bolts which had descended from the ash cloud created by Eyjafjallajokull.They combined these findings with radar information on the height of the cloud to work out if there was any connection between the two.
There was.When the cloud’s maximum altitude was less than 5km (3 miles),ATDnet detected no lightning from it.The number of strikes went up as the maximum altitude increased.Sudden changes in altitude also pushed the strike-rate up.More than 20 bolts an hour indicated a rapid rise of more than 1km.
In the case of Eyjafjallajokull,the watchful eye of Icelandic radar meant the cloud’s behaviour was reasonably well understood,even at the time.But radar can be blinded by bad weather,and not all volcanoes are within range of suitable equipment.Next time a volcano threatens the air lanes,then,Dr Bennett’s method may provide valuable illumination of what is happening,and thus enable airliners to steer safely through what might otherwise ground them.

let's look back last 10 decades. What we people have been learning from the natural world. Of course, the revolution of inventions. But which one should be the significant that influences the whole wo...

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let's look back last 10 decades. What we people have been learning from the natural world. Of course, the revolution of inventions. But which one should be the significant that influences the whole world completely. Absolutely , the internal should be the one. Internet to folks is not strange, but well-known.At present, I am browsing websites by using INTERNET . Without it, i can not imagine what the world could be. Nowadays , people can through cyber connection to exchange information, view and intelligent. It is more easy for people to bridge communication than ever before.
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Comment on one greatest invention or discovery in 21century ：
let's look back last 10 decades. What we people have been learning from the natural world. Of course, the revolution of inventions. Bu...

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Comment on one greatest invention or discovery in 21century ：
let's look back last 10 decades. What we people have been learning from the natural world. Of course, the revolution of inventions. But which one should be the significant that influences the whole world completely. Absolutely , the internal should be the one. Internet to folks is not strange, but well-known.At present, I am browsing websites by using INTERNET . Without it, i can not imagine what the world could be. Nowadays , people can through cyber connection to exchange information, view and intelligent. It is more easy for people to bridge communication than ever before.
With the aid of the computer and its internet,the human way of thinking and the style of living are changing so greatly that many of the young people have nearly forget the social tradition.And there used to be a heated discussion on the topic whether the internet is good or not.With the development of the science,especially facing with the convenience that the internet has brought us,people have to make their own choice.
Persinally I think,internet is a developed science and technology appeared in the social development,it certainly will have some good or bad influence on the things happened in the past,such as tradition and custom.But we have to admit that the internet is giving us more and more confluence and new concepts that we have never seen,experienced and even thought of. Nobody can escape from the net ,for it appears in every corner of our lives,for instance, banking transportation, communication, design,schooling and so on.

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你好，交大学生，我是你英美文化课的老师，你的行为我已经看到了，回答的文章我也读了，如果我发现如有雷同，按零分算。。。学习要自己动脑，不要光靠别人，懂了吧。本人：邹。。。

啊~~哈哈，被老师发现了吧，同情同情。。。