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Copper wire competitive with fiber optic cable: Researchers

Himtimes-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

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: Study

Himtimes-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 era

Himtimes-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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