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NEWSBITS
PAKSAT-1 to start functioning Feb 1
Right on target, Pakistan’s first commercial satellite (PAKSAT-1) has reached its orbital position at 38 degrees East and has completed its initial manoeuvres to lock itself in a geo-synchronous orbit, 36,000km above the Earth. Chairman National Telecommunication Corporation (NTC) Air Vice-Marshal Azhar Maud stated this at a presentation last Sunday to the press regarding PAKSAT-1, a Hughes Global Systems Satellite. He said the satellite, which has been hired with a total cost of US$30 million for the next five year, is an additional source and will start functioning from Feb 1.
Azhar Maud further informed that a limited use of this satellite would begin in order to earn some revenues and, as an additional advantage, use it for educational, internet and data networking at very low cost. Giving the background of the satellite, he said, President General Musharraf and his cabinet took a bold and considered decision last year to go flat out to acquire a satellite and position it in Pakistan’s orbital slot at 38 degrees East. This slot was due to expire on April 19, 2003, after which Pakistan would lose all chance of ever being able to put its own satellite in orbit, he added.
Dr Atta-ur-Rahman was assigned this task and a high level committee, comprising different ministries, was tasked to guide this project to a successful completion, he said. According to reports received from Frequency Allocation Board in Islamabad and SUPARCO in Lahore, the satellite has stabilized at its new location and its beacons were successfully received at the monitoring centres. The chairman said the satellite would be ready for commercial operations after comprehensive in-orbit testing and ground coverage surveyby end Jan 2003.
Its beacon frequencies, which are being continuously transmitted, are being received at the Telemetry, Tracking and Control Stations in Perth, Australia after being relayed from Rugby in England. These are also being monitored at SUPARCO, Lahore and the Frequency Allocation Board (FAB) facilities in Islamabad. He said the satellite is undergoing its in-orbit testing to determine the health of its various components. The actual transponder testing will start in early January, when the phased usage of its 34 C+ Ku band transponders will begin, he added.
Five slots were allocated to Pakistan in the geo-stationary orbit in the past, which could not be exploited by the successive governments. The last of Pakistan’s slot at 38 degree East was due to expire on April 19, 2003. “If this slot was not protected by bringing in a satellite and placing it there, this strategic asset and any future opportunity for Pakistan to enter the space would have been lost forever,” he added. He said Pakistan acquired this July the use of this in-orbit satellite from Hughes Global System (HGS) of the United States at a very low cost, enabling the country to protect its right at the orbital location, while the planning is taking place for a follow-on satellite to fully exploit the slot. — Dawn ScienceDotcom Report
Web recovers from worm attack
The worm that wreaked havoc on the internet over the last weekend finally lost steam on Monday.
The “SQL Slammer” bug, that hit with the most damaging web attack in 18 months nearly shut down web access in many countries and paralyzed corporate networks. There were internet slow-downs on Monday. Yahoo Inc, one of several major US internet businesses to downplay the impact of the attack, said the fast-spreading worm had disrupted video and audio streaming services for a few hours last Saturday.
“You’ll see variants out there,” said Bruce Schneier, Chief Technology Officer of networking monitoring company Counterpane Internet Security.
Schneier said some of the steps taken to prevent SQL (pronounced “sequel”) Slammer from spreading to other networks were stop-gap measures that could be easily overcome, raising the threat of more attacks on the flow of information and data across the web.
The worm spreads through network connections rather than via e-mail. The malicious code exploits a weakness in Microsoft’s Windows 2000 SQL server database software, although it does not delete or otherwise touch data. It caused servers to crash and congested traffic on the global network.
Security advisors warned that the worm was designed to rapidly infiltrate networks and that it would continue to do so until servers were sufficiently patched.
Microsoft has developed a patch that can be downloaded at: http://www.microsoft.com/technet/treeview/default.asp?url=/tech net/security/bulletin/MS02-039.asp.
Microsoft’s top security strategist Scott Charney said that the world’s largest software maker was reaching out to its SQL customers to urge them to download the patch.
“The single largest message is: keep your system up to date with patches,” Charney said.
Genes marveled at the design of Slammer, noting that its tiny size of 376 bytes — about as dense as the subject line of an e-mail message — enabled it to spread quickly. As is often the case, the worm’s author left no indication of his location or motive, Genes said. — Dawn ScienceDotcom Report
Fossils of four-winged dinosaur discovered
Recently discovered fossils of feathered dinosaurs with four wings are raising new questions about the origins of flight.
The turkey-sized creatures probably lived in the trees about 130 million years ago and used their wings and long tail to glide from branch-to-branch.
The six specimens belong to a new dinosaur family that may have played a key role in the evolution of birds. They were unearthed in Liaoning, China - a place that has yielded many spectacular fossils of bird-like dinosaurs.
The find is exciting because it backs an older theory that birds evolved from gliding four-winged tree-dwellers.
The idea was first raised in 1915 but until now there has been no fossil evidence to support it. According to the Chinese team that found the specimens — led by Xing Xu of the Institute of Vertebrate Paleontology and Paleoanthropology in Beijing - this may be the first confirmation.
“Although the dinosaurian hypothesis of bird origins is widely accepted, debate remains about how the ancestor of birds first learned to fly,” the scientists report in the journal Nature.
“Here we provide new evidence suggesting that basal dromaeosaurid dinosaurs [a sub-group of theropod dinosaurs] were four-winged animals and probably could glide, representing an intermediate stage towards the active, flapping-flight stage.”
The suggestion is that dinosaurs went through a gliding stage before learning to fly with two fore-limbs, says Dr Angela Milner of London’s Natural History Museum.
Rival camps: Scientists will now want to look again at the fossils of the earliest bird, Archaeopteryx, to see if there are any vestiges of hind-wings.
“The importance of this find is that it gives us one more piece of evidence as to how flight got started,” said Dr Milner.
“This is clearly a small dinosaur, but equipped for climbing and with well developed feathers on its arms which have flight capability and assisted by gliding feathers on its hind legs.” The question of how flight arose has caused much heated debate. Many dinosaur experts belong to a rival camp - that birds evolved from ground-living dinosaurs with powerful hind-limbs adapted for running.
The discovery of the four-winged fossils — cousins of the previously described as Microraptor — is unlikely to be the end of the story. — Dawn ScienceDotcom Report
Computer boosts memory by 10pc
Scientists believe they may have found a way to improve our memory by as much as 10 per cent. Researchers at Imperial College, London, have used a technique called neurofeedback to train people to remember more clearly. It works by showing people their own brainwaves on a computer screen, and teaching them how to control them.
Doctors believe it could one day be used as a treatment for people with attention deficit hyperactivity disorder, epilepsy and other similar conditions affecting the brain.
Brain activity is monitored through sensors attached to the scalp. The patient can see the brainwaves on a screen.
This enables them to see how different moods and behaviour affects the brain. They are then taught how to control their brain activity and correct or stabilise it.
Memory tests: Dr David Vernon tested the technique on 40 people. They each had a memory test before and after their neurofeedback session.
They were presented with a series of words which related to specific categories. They were then given the categories and asked to recall related words. Those who underwent neurofeedback were able to recall 82 per cent of the words after their session. This compares to just 71 per cent prior to the treatment. In comparison, a group of people who did not undergo neurofeedback saw their recall rate increase from 73 per cent to just 75 per cent.
Dr Vernon said: “Previous research has indicated that neurofeedback can be used to help treat a number of conditions including attention deficit hyperactivity disorder, epilepsy and alcoholism by training particular aspects of brain activity. “But this is the first time we have shown a link between the use of neurofeedback, and improvements in memory.”
Professor John Gruzelier, from Imperial College London at Charing Cross Hospital said further study is needed. But he suggested the technique could help patients who have brain damage or memory problems.
“Neurofeedback has been proven to be effective in altering brain activity, but the extent to which such alterations can influence behaviour are still unknown.
The study is published in the International Journal of Psychophysiology. — Dawn ScienceDotcom Report
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