Innovation and Technology Weekly – No. 4, 2009

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Issue 4, 2009

This week's headlines:

China builds super-sized radio telescope
January 27, 2009

Construction has begun on a massive new 500m diameter radio telescope in Guizhou Province, China, that will allow astronomers to detect galaxies and pulsars at unprecedented distances. The facility, known as the Five-hundred-meter Aperture Spherical Telescope (FAST), will boast a collecting area equal to 30 football fields - more than twice as big as the 305 m diameter radio telescope at Arecibo Observatory in Puerto Rico, which has been the world's largest since it opened in 1964.

The geography and remoteness of FAST's site make it very radio-quiet. The new telescope will sit in a natural karst depression that mimics the shape of the collecting surface, simplifying the support structure and shielding the telescope from stray human-generated radio waves. The site's potential for long, uninterrupted observations - coupled with the telescope's huge size - means that researchers will be able to detect objects like weak, fast-period pulsars that are too faint to be measured accurately by smaller instruments.

In addition to being big, FAST is designed to be flexible: a system of motors attached to its 4600 panels will allow astronomers to change its shape from a sphere to a paraboloid, making it easier to move the position of the telescope's focus. This will allow the south-pointing telescope to cover a broad swathe of the sky - up to 40 degrees from its zenith, compared to the 20-degree-wide strip covered by Arecibo.

Full story: Physics World Back to top

Cheap, super-efficient LED lights on the horizon
January 29, 2009

UK scientists have discovered a cheaper way to produce LED bulbs, which are three times as efficient as fluorescent lamps.

Gallium nitride (GaN) LEDs have many advantages over compact fluorescent lamps (CFLs) and incandescent bulbs. They switch on instantly, with no gradual warm-up, and can burn for an average of 100,000 hours before they need replacing. CFLs also contain small levels of mercury, which makes environmentally-friendly disposal of spent bulbs difficult.

The cost of production has kept the LEDs far from homes and offices, however. Gallium nitride cannot be grown on silicon like other solid-state electronic components because it shrinks at twice the rate of silicon as it cools. Crystals of GaN must be grown at 1000°C, so by the time a new LED made on silicon has cooled, it has already cracked, rendering the devices unusable.

Now researchers at the University of Cambridge have discovered a simple solution to this problem. They included layers of aluminium gallium nitride in their LED design. These layers shrink at a much slower rate during cooling and help to counteract the fast-shrinkage of pure gallium nitride. These LEDs can be grown on silicon as so many other electronics components are. A 15-centimetre silicon wafer costs just USD 15 and can accommodate 150,000 LEDs making the cost per unit tiny.

Full story: New Scientist Back to top

Novel technology could produce cheap biofuel
January 29, 2009

A novel technology for synthesising chemicals from plant material could produce liquid fuel for just over EUR 0.50 a litre, say German scientists at the Karlsruhe Institute of Technology (KIT). But only if the infrastructure is set up in the right way.

The novel technology is known as bioliq, and is able to produce a range of different types of liquid fuel and chemicals from plant material such as wood and straw. Bioliq involves first heating the plant material in the absence of air to around 500°C. This produces a thick oily liquid containing solid particles of coke termed biosyncrude.

The biosyncrude is then vaporised by exposing it to a stream of oxygen gas, before being heated at high pressures to a temperature of around 1400°C. This gasification process transforms the liquid biosyncrude into a mixture of carbon monoxide and hydrogen called syngas. After any impurities are removed from the syngas, it can be catalytically converted into a range of different chemicals and fuels, including methanol, hydrogen and a synthetic version of diesel.

Full story: EurekaAlert / Biofuels, Bioproducts & Biorefining Back to top

Balloon power isn't just a load of hot air
January 18, 2009

For those who dislike the sight of wind turbines on the horizon, would a spectacular hot-air balloon farm be more acceptable?

Ian Edmonds, an environmental consultant with Solartran in Brisbane, Australia, has designed a giant engine with a balloon as its 'piston'. A greenhouse traps solar energy, providing hot air to fill the balloon. As the balloon rises, it pulls a tether, which turns a generator on the ground. Once the balloon has reached 3 kilometres, air is released through its vent and it loses buoyancy. This means less energy is needed to pull the balloon back down again, resulting in a net power gain.

For roughly the same cost as wind power, Edmonds has calculated that a large 44-metre-diameter recreational balloon could generate 50 kilowatts, enough to supply energy to about 10 homes. Doubling the diameter of the balloon would increase power production tenfold, substantially reducing costs.

Full story: New Scientist / Renewable Energy Back to top

Physicists raise serious LHC safety doubts
January 29, 2009

New research by three physicists has raised concerns over the safety of the Large Hadron Collider (LHC), which is due to restart this summer.

Concerns had already been raised that the activities within the 27km particle accelerator could create black holes, which could in turn destroy the planet. A lawsuit was even filed to prevent the LHC from operation which sparked ribaldry from internet users.

CERN, which operates the LHC, commissioned an extensive study which concluded that, if black holes were formed by the LHC, they would last for only milliseconds before extinguishing themselves. However, a new study by Roberto Casadio of the University of Bologna, and Sergio Fabi and Benjamin Harms of the University of Alabama, has concluded that the black holes could survive for more than a second.

The danger would occur if the black holes stayed in existence long enough to absorb material and become self-sustaining, but the physicists say it is more likely that they would either collapse or stabilise at a very small level and drift out into space.

Full story: VNUnet UK Back to top

Alarm sounded over Wi-Fi networks
January 27, 2009

Wireless access points could be used by hi-tech criminals to spread viruses and worms, warn researchers at Indiana University. Security holes and the popularity of the devices in cities makes them ideal for spreading malware, they found.

Using modelling methods from real diseases the team showed how a worm could gradually infect all access points in urban areas. They found that the majority of vulnerable access points would be hit in the first 24 hours of an outbreak. The simulation work showed that within two weeks of an outbreak occurring 55% of Wi-Fi access points would be compromised. In urban areas this could mean tens of thousands of people were at risk, said the researchers.

The theoretical attack modelled by the team involved attempts to subvert the firmware inside a Wi-Fi access point or router which keeps the device running. Hi-tech criminals keen to subvert Wi-Fi access points could rely on the fact that few people take basic steps to stop unauthorised access to the device, said the researchers. The team recommended that people be forced to change default passwords and encouraged to use encryption - both of which can limit the ability of wireless-borne malware to spread.

Full story: BBC News Back to top

Invention: Sleepy driver sensor
January 23, 2009

Around 20% of accidents on multi-lane highways are the result of driver fatigue. So the Japanese car maker Toyotahas developed a system to rouse drivers before they quite literally drift off completely.

A camera watches the white lines on the road ahead to determine if and how fast the car is veering towards or away from them. An onboard computer then decides whether that kind of manoeuvre is appropriate for the situation. If it is deemed potentially dangerous, the system raises the alarm to wake the driver.

For example, a car regularly crossing white lines while accelerating and braking is likely to be simply driving in city traffic. But wobbling to and fro within a lane, or gradually veering across white lines while moving at a constant high speed may indicate a driver falling asleep on the open highway. If the driver is judged to be losing consciousness, the computer raises an alarm to wake the driver.

Full story: New Scientist Back to top