Tag Archives: technology

Advance brings low-cost, bright LED lighting closer to reality

Original, July 17, 2008 http://news.uns.purdue.edu/x/2008b/080717SandsLighting.html

 WEST LAFAYETTE, Ind. – Researchers at Purdue University have overcome a major obstacle in reducing the cost of “solid state lighting,” a technology that could cut electricity consumption by 10 percent if widely adopted.

The technology, called light-emitting diodes, or LEDs, is about four times more efficient than conventional incandescent lights and more environmentally friendly than compact fluorescent bulbs. The LEDs also are expected to be far longer lasting than conventional lighting, lasting perhaps as long as 15 years before burning out.

“The LED technology has the potential of replacing all incandescent and compact fluorescent bulbs, which would have dramatic energy and environmental ramifications,” said Timothy D. Sands, the Basil S. Turner Professor of Materials Engineering and Electrical and Computer Engineering.

The LED lights are about as efficient as compact fluorescent lights, which contain harmful mercury.

But LED lights now on the market are prohibitively expensive, in part because they are created on a substrate, or first layer, of sapphire. The Purdue researchers have solved this problem by developing a technique to create LEDs on low-cost, metal-coated silicon wafers, said Mark H. Oliver, a graduate student in materials engineering who is working with Sands.

Findings are detailed in a research paper appearing this month in the journal Applied Physics Letters, published by the American Institute of Physics.


Quantum Leap: Researchers have controlled the position of a single electron in a silicon circuit.

Original, July 17, 2008: http://www.technologyreview.com/Infotech/21086/?a=f

An international team of researchers has shown that it can control the quantum state of a single electron in a silicon transistor–even putting the electron in two places at once. Their discovery could help pave the way toward a practical quantum computer.

Quantum computers take advantage of the strange properties of subatomic particles to perform certain types of calculations much faster than classical computers can. Researchers are exploring a host of different approaches to quantum computing, and some have even built primitive quantum circuits that can perform calculations. But practical quantum computing would require the ability to manufacture devices with millions of quantum circuits–rather than the 12 or 16 achievable now–that can be integrated with more-conventional electronics.

Questioning the Coming Internet Clog by Ed Gubbins

Original, August 15, 2008 http://telephonyonline.com/home/news/internet-traffic-growth-decelrating-0805/

One of the nation’s top authorities on global Internet traffic growth says his latest data show no reason to fear network capacity shortages, as traffic growth may even be slightly decelerating.

Updating data collected from Internet exchanges around the world, professor Andrew Odlyzko, director of the University of Minnesota’sInterdisciplinary Digital Technology Center,reported late last week that Internet traffic rates in the US and globally are continuing to grow at a rate between 50% and 60% (largely unchanged from recent years) — rapid growth that nonetheless belies dire predictions of an escalation that would clog today’s networks.

“There is still not [sic] sign of the threatened deluge that was supposed to clog the Internet,” Odlyzko wrote in an email late last week announcing the new data. “Growth rates, if anything, are tending down.”

Digitizing Old Text and Fighting Spam, Too by Phil Berardelli

Original, August 12, 2008 http://sciencenow.sciencemag.org/cgi/content/full/2008/814/1 


The next time a Web site asks you to read a string of crooked letters as a security precaution, don’t grimace. You could be helping to digitize a deteriorating historical document. A team of computer scientists has taken a common Internet tool for screening out spam and adapted it to help convert text from old books and manuscripts into electronic files. The effort might not put professional transcribers out of business, but it could cut the cost of creating digital libraries. 


In the battle between Web security designers and spammers, programs called Completely Automated Public Turing test to tell Computers and Humans Apart (CAPTCHA) have proven an effective foil. The programs require online users to read a distorted word or line of text and retype it in a designated box–something that few optical scanners or digital-text readers can do. Insidious programs deployed by spammers can penetrate sites such as Gmail and lift their e-mail address lists. CAPTCHAs block the attempt by requiring an extra step before providing access. They are used online about 200 million times every day.

 Computer scientist Luis von Ahn of Carnegie Mellon University in Pittsburgh, Pennsylvania, and colleagues thought all that effort could be put to another use, too. “Since each [CAPTCHA] takes about 10 seconds of human time,” von Ahn says, “we figured humanity as a whole was wasting about 500,000 hours every day typing.” And that much time constituted a valuable resource in efforts to digitize old books with deteriorating pages and faded text.


Solar Power to Rule in 20 Years, Futurists Say by Robin Lloyd

Original: http://www.livescience.com/environment/080219-kurzweil-solar.html

BOSTON — He predicted the fall of the Soviet Union. He predicted the explosive spread of the Internet and wireless access.

Now futurist and inventor Ray Kurzweil is part of distinguished panel of engineers that says solar power will scale up to produce all the energy needs of Earth’s people in 20 years.

There is 10,000 times more sunlight than we need to meet 100 percent of our energy needs, he says, and the technology needed for collecting and storing it is about to emerge as the field of solar energy is going to advance exponentially in accordance with Kurzweil’s Law of Accelerating Returns. That law yields a doubling of price performance in information technologies every year.

Kurzweil, author of “The Singularity Is Near” and “The Age of Intelligent Machines,” worked on the solar energy solution with Google Co-Founder Larry Page as part of a panel of experts convened by the National Association of Engineers to address the 14 “grand challenges of the 21st century,” including making solar energy more economical. The panel’s findings were announced here last week at the annual meeting of the American Association for the Advancement of Science.