Tuesday, January 17, 2006
Robotic hand translates speech into sign language
An 80-centimeter robotic hand that can covert spoken words and simple phrases into sign language has been developed in a town in Fukuoka Prefecture.
The robotic hand was shown at a two-legged robot tournament held at the Fukuoka Prefecture Education Center in Sasagurimachi, where it won applause from appreciative spectators.
A microchip in the robot recognizes the 50-character hiragana syllabary and about 10 simple phrases such as "ohayo" (good morning) and sends the information to a central computer, which sends commands to 18 micromotors in the joints of the robotic hand, translating the sound it hears into sign language.
The aluminum robot was developed by a team led by the center's head instructor Keita Matsuo, 39, and Hirotsugu Sakai, 38, who is attending a long-term training program for schoolteachers.
The two men came up with the idea when they visited a school for the hearing-impaired and communicated with students through an interpreter who signed for them.
"We wondered if it would be possible to communicate with them via robots," Matsuo said.
They studied a book on sign language, and spent about two months creating the system, increasing the number of joints in the hand to 18 so that it could sign smoothly.
They added that in the future, hundreds of thousands of words could be programmed into the voice recognition unit and the robotic hand could function as a receptionist.
The robot was shown to teachers at the school in December to ensure that its sign language was understandable.
In addition to the signing robot, the event, attended by 160 students from middle school and technical high schools, featured a race among bipedal robots developed by six high school teachers.
source:http://www.yomiuri.co.jp/dy/features/culture/20060116TDY19003.htm
Is dark energy changing?
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By observing distant, powerful bursts of gamma rays (
-rays), Brad Schaefer says he has preliminary evidence that the strength of dark energy is different today from when the Universe was very young. Schaefer, an astronomer at Louisiana State University in Baton Rouge, presented his results at an American Astronomical Society meeting in Washington DC.Just minutes after the data were presented in a late afternoon session, some astronomers were already calling the bold claim into question.
An idea that arose in the late 90s, dark energy seems to act over very large distances, pushing the Universe apart at an ever increasing speed. At the moment, many researchers believe that dark energy may be a foam of quantum particles that exists throughout the vacuum of space. Under that scenario, dark energy would be a constant and unchanging force, according to Michael Turner, a cosmologist from the University of Chicago, Illinois.
Schaefer's findings, if they are true, would turn that idea on its head.
Big, bright bursts
Schaefer began by examining 52 bursts of high-energy
-rays that were recorded by six satellites. The bursts came from the explosions of distant, super-massive stars that were billions of light years away. The explosions were so distant that the ones we see now occurred when the Universe was only 1.5 billion years old, a tenth of its current age. Schaefer used various properties of the bursts, such as the way their brightness changed over time, to work out how intrinsically bright they were and how far away the explosion was. Twelve of the most distant of the bursts examined by Schaefer turned out to be brighter than would be expected if dark energy had remained a constant.
"I would not characterize this as proof," Schaefer cautions. "Before we can be confident, we will have to see these results reproduced."
The old ways
Many questions surround Schaefer's result, says Dieter Hartmann, a
-ray astronomer at Clemson University in South Carolina. For one, says Hartmann, the findings are dependent on understanding just how the ancient, massive stars lived and died. "The births of these stars will be different, and the environment in which they ultimately explode is different," he says. Without understanding the physics of these explosions, the estimate of their intrinsic brightness is very uncertain, he says.
Others are still more sceptical. "I think he's wrong," says Adam Riess, an astronomer at the Space Telescope Science Institute in Baltimore, Maryland. Riess says that Schaefer's failure to include nearby and recent
-ray bursts to calibrate the results make his conclusions about the much more distant bursts highly questionable."This is an intriguing result," admits Turner. But it certainly doesn't add up to a Nobel prize without further confirmation, he says. "I don't think it's a ticket to Sweden."
source:http://www.nature.com/news/2006/060109/full/060109-11.html
