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BBC新闻:Facebook计划用太阳能无人机提供互联

发布者: Candy_hao | 发布时间: 2016-8-9 15:09| 查看数: 1130| 评论数: 0|



The social network Facebook says it's planned to use solar powered drones to provide internet access to millions of people in the developing world. The first of the devices built by a team in southwest England has successfully taken to the skies in the United States. Facebook hopes that the drones will eventually be able to stay in the air for months and deliver internet to villages in Africa and India using invisible lasers. Here is our technology correspondent Rory Cellan-Jones.

Two years ago, Facebook bought a centre, a small firm which specialized in making drones. Its plan was to use it in an ambitious project to connect remote places in Africa and elsewhere to the Internet. A team in Bridgewater has now built a solar powered aircraft with a wingspan of a Boeing 737 but weighing a third as much as a car. Now the social network has reviewed that the first flight with the unmanned plane has taken place in Arizona. It was airborne for 90 minutes. But Andy Cox the British engineer running the project says that is just a start.

Facebook plans to build a fleet of these drones which will beam an internet signal to people within a sixty-mile diameter. But it will be some years before the drones are ready to go into service. And in the meantime, other technology firms, notably Google are attempting something similar.

It was twenty years ago that Dolly the sheep became the first mammal ever to be cloned from the cell of an adult animal. Dolly died young at the age of six. But research on cloning techniques is continuing and Dolly has sisters for identical sheep all cloned from the same adult.

Scientists want to know whether they like Dolly are going to die young and if they age in a normal way.

I'm feeling the joints for any kind of heat or swelling. And then we can pick up the leg and gently manipulate them to check that they flex and extend as normal. Veterinary surgeon puts Daisy the sheep through a very hands-on physical examination.

You can see she is not really bothered by that at all.

But Daisy is not just any sheep. She is a clone, one of her flock of thirteen clone sheep currently living out their lives on a farm owned by the University of Nottingham. And one of only four, the others are Debby, Denis and Dian cloned from the same adult is Dolly the sheep, the first clone mammal born in 1996, which despite the passage of a couple of generations in sheep years makes them Dolly's identical twins sisters.

Rory Cellan-Jones.


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