The seventh-grader's explanation was that

小云儿

A seventh-grader from New York has worked out that solar panels arranged more like tree branches may capture more light than flat panels.

(Credit: wireless, cellular)
For real, kind of. Aidan Dwyer, 13, noticed that tree branch patterns are Fibonacci numbers, postulated that it had to do with photosynthesis, took some pretty involved measurements of an oak tree, built a PVC-pipe solar array in the same shape, built a the north face cheap flat solar panel, compared how much light each captured over time, and voila, he had an award-winning science experiment and a great-sounding theory: trees evolved with these patterns for good reason. He found that tree-shaped pattern is as much as 50 percent more efficient than the flat panel, depending on the time of year.

The seventh-grader's explanation was that the Fibonacci pattern keeps branches out of each others' shadows in full light and at the same time allows the tree to garner as much light as possible when some branches are in shadow and others in light.

Dwyer wrote up the results in an essay that includes details of a winter hike in the Catskills, the centuries-old history of humans noticing these patterns throughout nature (from shell structure to Galaxy shape), and a nice description of the way Fibonacci north face clothing explained the numbers using the rabbit birthrate and Sanskrit poetry. The essay won the American Museum of Natural History Young Naturalist award.

Here's where the story takes an interesting turn. More than one scientist has poured cold water on Dwyer's theory, while others have cautioned not so fast. It's a good lesson in the importance of peer review before publishing. Just as tree branches are arranged the way they are for a reason, so are today's silicon solar cells.

And even if Dwyer's experiment holds up to scrutiny, there's a lot involved in making a successful solar module. After theory, proof of concept, peer review, and one or more back-to-the-drawing-boards, you still have cost of manufacturing and competition with other technologies.

But the kid isn't necessarily barking up the wrong tree. Some of the world's leading energy researchers are working on mimicking trees. The key is using inexpensive solar cells that work well in diffuse light.

Dwyer's next move is to study different kinds of trees to find the most efficient design for his PVC solar array. He's also applied for a patent.

Nice work for junior high. I hope Dwyer falls in with some inspiring science teachers. And I like his DIY attitude. So what's this kid going to do in high school? I've got a suggestion--once you've solved the energy problem (even if this first attempt doesn't do the trick), how about moving on to the global food crisis?
The wire columbia jackets less carriers' investment in 4G networks could be the salve that the ailing U.S. economy is looking for.
The carriers could invest between $25 billion and $53 billion in building out their 4G network through 2016, according to a study from Deloitte. That in turn could lead to the creation of 371,000 to 771,000 jobs, and gross domestic product growth of $73 billion to $151 billion.

"Investment in such a powerful form of communication contributes to the economic recovery and provides a job-creating engine for the future," said Phil Asmundson a consultant for Deloitte.

The rise of 4G networks could provide some support for an economy still struggling to recover, and which some believe is slipping back into a recession. The recent bitter political struggle to raise the national debt ceiling, the sharp declines in the stock market, and the continued high rate of unemployment have many still concerned.

The wide-ranging estimate assumes two different scenarios. The baseline scenario has the carriers deploying 4G technology at a moderate pace with a slow transition from 3G to 4G extending into the middle of the decade. Deloitte warns that under these conditions, the U.S. firms will be vulnerable to foreign competitors looking to jump ahead in the 4G race.

The second herve leger scenario predicts a more rapid investment in 4G networks and the creation of 4G-based services before global competitors gain momentum. Deloitte said the demand stimulated by the new services would propel more network investment, "setting off a virtuous cycle of investment and market response." Cloud services are among the primary catalysts for investment, according to Deloitte.

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全英文呀。。。。看不懂。 谁来翻译下。