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Science &
Technology
| Science & technology
Copper wire competitive with fiber optic cable: ResearchersHimtimes-ANI
News
Washington, Dec. 7: Penn State
engineers have developed and simulation tested a copper wire transmission
scheme for distributing a broadband signal over local area networks (LANS)
with a lower average bit error rate than fiber optic cable that is 10
times more expensive. "Our approach can improve the
capability of existing local area networks and shows that copper is a
competitor for new installations in the niche LAN market," says Dr. Mohsen
Kavehrad, the W. L. Weiss professor of electrical engineering and director
of the Center for Information and Communications Technology Research.
The Penn State approach
responds to the IEEE challenge to specify a signaling scheme for a next
generation broadband copper Ethernet network capable of carrying broadband
signals of 10 gigabits per second. "In the existing copper gigabit
systems, each pair of wires carries 250 megabits per second. For a 10
gigabit system, each pair will have to carry 2.5 gigabits per sec,"
Kavehrad explains. "At these higher speeds, some energy penetrates into
the other wires and produces crosstalk." The Penn State scheme
eliminates crosstalk by using a new error correction method they developed
that jointly codes and decodes the signal and, in decoding, corrects the
errors. The Penn State approach also
takes account of the reduction or loss of signal energy between one end of
the cable and the other that can become severe in 100 meter copper
systems. A MATLAB simulation has shown
that the scheme is possible and can achieve an average bit error rate of
10 to the minus 12 bits per second. Fiber optic cable typically achieves
10 to the minus nine. The work is continuing. BBC "soap opera" of his scientific work irks Stephen Hawking!Himtimes-ANI
News
London, Dec.06 : Famed
scientist Stephen Hawking is furious with the BBC network for turning a
planned drama about his life into a "soap opera". The 61-year-old author of A
Brief History of Time, who suffers from motor neurone disease, is unhappy
at the script's portrayal of his illness and his private life, says a
report in rate the music.com. Hawking says, "It was a soap
opera which bore little relation to my scientific work. I asked them to
come back with another." The BBC confirms, "Stephen has
asked for the first script to be reworked." Microwaves won't disturb you anymore!Himtimes-ANI
News
Washington, Dec. 4: A simple
discovery by University of Michigan College of Engineering scientists, has
enabled them to significantly reduce interference from microwave ovens in
other electronic appliances placed near them. Worldwide, there are hundreds
of millions of microwave ovens in kitchens, offices and laboratories, each
with a magnetron that creates communications problems ranging from an
aggravating crackle during a friendly telephone call, to the disruption of
911 calls and the flow of data in wireless computer networks.
Although these effects are
difficult to quantify, it's safe to say they're an annoyance, an economic
drain and potentially life- threatening. The basic difficulty is that
microwave ovens operate at a frequency near 2.45 GHz - about the same
frequency at which telephones and wireless computers operate. In the
microwave oven there are two magnets, one at each end of the magnetron.
The research team, lead by
Prof. Ronald Gilgenbach found that when they added four permanent magnets
to the outside of one of the standard magnets, they could disrupt the
magnetic field in such a way that it becomes benign to nearby electrical
devices, yet doesn't significantly affect the performance of the microwave
oven. The discovery could also have
an enormous impact on the signal- to-noise ratio in radar and in the
development of a power source for inexpensive deep-space exploration, and
advanced electroporation for highly improved cancer
treatment. Nature triumphs over nurture, when it comes to behavior: StudyHimtimes-ANI
News
Washington, Dec.4 : Using
monkeys, researchers at the University of Chicago have been able to
demonstrate the importance of nature over nurture in behavior, when these
animals are taken away from their biological mothers at birth.
Young monkeys reared by a
mother other than their own are more likely to exhibit the aggressive or
friendly behavior of their birth mothers rather than the behavior of their
foster mothers. The discovery of inheritability
of social behavior traits among non-human primates has important
implications for people as it reinforces other research that suggests that
such characteristics as sociability and impulsive aggressiveness among
humans may have a genetic basis, said Dario Maestripieri, Associate
Professor in Human Development at the University. Rhesus macaques provide an
important research population because they organize in strong matrilineal
structures, and the female offspring often exhibit the same social
behavior as their mothers. The experiment was intended to show if some
aspects of that behavior were inherited or learned by the female
offspring. For the study, Maestripieri and
his colleagues swapped rhesus monkey female babies between mothers who had
recently given birth. To understand the origins of
behavior, the team looked at the expression of social contact and
aggression among the offspring and their biological and foster mothers.
When Maestripieri looked at the
behavior of the monkey offspring and their mothers over the span of three
years, he found that while the offspring's behavior mirrored the behavior
of their biological mothers, there was practically no similarity between
the offspring and their foster mothers. Primate expert Joan Silk,
Professor of Anthropology at the University of California, Los Angeles,
said, "This study adds to a growing body of evidence that temperament and
behavioral predispositions vary among individuals and that temperamental
differences are stable over the life course. However, it is usually
difficult to determine whether such differences are the results of
inherited dispositions and/or the effects of environment and experience.
"Using an innovative design to
disentangle the effects of 'nature' and 'nurture,' Maestripieri
demonstrates that heredity has a surprisingly important impact on the
behavioral dispositions of infant macaques. These findings have important
implications for understanding how evolution shapes behavior and
temperament in primates and humans," she added. Defect-free hybrids to herald super-electronics eraHimtimes-ANI
News
Washington, Dec. 3: Ohio State
University engineers have overcome a major barrier in the manufacture of
high quality light emitting devices and solar cell materials.
Steven Ringel, professor of
electrical engineering, and his colleagues have created special hybrid
materials that are virtually defect-free, an important first step for
making ultra- efficient electronics in the future. The findings show that the same
technology could also lead to faster, less expensive computer chips.
Ringel directs Ohio State's
Electronic Materials and Devices Laboratory, where he and his staff grow
thin films of "III-V" semiconductors materials made from elements such as
gallium and arsenic, which reside in groups III and V of the chemical
periodic table. Because III-V materials absorb
and emit light much more efficiently than silicon, these materials could
bridge the gap between traditional silicon computer chips and
light-related technologies, such as lasers, displays, and fiber optics.
Researchers have tried for
years to combine III-V materials with silicon, but only with limited
success. Now that Ringel has succeeded in producing the combination with
record quality, he has set his sights on a larger goal.
"Ultimately, we'd like to
develop materials that will let us integrate many different technologies
on a single platform," Ringel said. |
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