Versatile application of advanced materials
by Radhakrishna Rao
OVER the last two decades rapid advances in industrial processes have resulted in the evolution of a whole new range of advanced materials with a wide ranging applications.

Jupiter’s moon has oceans?
Astronomers say they have found even more evidence that Jupiter’s moon Europa and perhaps a second moon, Callisto, have liquid oceans under their icy crusts, reports Reuter.

• Cybersurfing
• Science quiz
• New products and discoveries
  

Computers as weapons of war
by Mohinder Singh

PUTTING a computer in a weapon makes it much more formidable, whether it’s a missile or bomb, plane, ship or tank. Weapons fitted with miniaturised state-of-art computers are more precise, faster and lethal. Indeed computer technology is rapidly taking over the battlefield.

This is no news to the military brass. But laymen often fail to figure how computers have transformed today’s warfare.

In the Second World War, for instance, all effective bombing was carpet bombing as all bombs were dumb. After release they simply fell. Today each smart bomb has its own computer, video camera and guidance fins. Once a bomber points a laser beam at a target and releases bombs, each bomb’s computer homes in on the illuminated spot by adjusting its guidance fins.

A cruise missile carries computers that record exactly where it is at all times, thanks to radio contact with world-spanning satellites, and it has extensive electronic maps of where it’s going. It can be launched more than 2,000 km from the target and hit accurately within a few metres, delivering its deadly load of high explosives. Of course, cruise missiles are costly; the ones fired by Americans recently over Afghanistan were 1.3 million dollars apiece.

For its weight and size, an advanced warplane is one of the most expensive machines on the planet. Indeed it’s so expensive that extensively training pilots on it is a luxury most nations can’t afford. But then computer technology has come up with simulators so improved it’s now easy to believe you’re in a real plane.

Over half the cost of today’s advanced warplanes goes into computers. Target-finding computers pick out potential attack points hundreds of kilometres away at night and in bad weather. Still more computers track and relay target information to yet other computers that order the plane’s missiles and guns to seek and destroy targets. Other computers manage fuel consumption, check for hostile radar, continuously manipulate the warplane’s numerous controls for best flying, and the shortest and the safest flight path. And highly sophisticated computers even accept a few spoken commands if the pilot is disabled.

In fact, the human pilot is proving a restricting factor in the manoeuvrability of a modern warplane, besides being expensive to train and the risk to his life. It is quite likely that many warplanes of future would be pilot-less. Such a warplane can execute a vast and intricate sequence of very fast actions — something the human body is unable to withstand. Perhaps 20 years hence, an aerial attack by advanced militaries would consist of a single high-flying piloted aircraft directing a squadron of low-flying, small, cheap, fast, self-defending robot ground-attack planes. The directing aircraft needn’t even be airborne. It’s another matter, such an air traffic and ground-surveillance aircraft, which can track, identify, and disentangle over a thousand jets flying close together, currently costs in the region of 300 million dollars.

Today’s naval battles can be fought and won in minutes by combatants a hundred kilometres apart. The ship’s captain is no longer on the bridge with his binoculars but down below in a darkened control room bristling with computer screens. Enemies are not face to face but blips on a phosphorescent screen. With the time to decide measured in split seconds, computerised guns fire automatically on anything approaching the ship that looks like a missile. Sometimes a mistake could be made but perhaps human-computer systems make fewer mistakes today than unaided people did in the past.

Computer-aided sea mines can play endless tricks. They can be programmed to be active only at certain times, even letting certain ship go by to allay suspicion. Some blow only when a particular kind of ship passes by. Others stay at the bottom of the sea, instead of hanging around, making detection more difficult.

Advanced tanks — costing 4 to 6 million dollars apiece — are packed with computers. Their operators only see a computer-massaged version of the outside world through periscopes. And most firing is computer-controlled. Someday there could be unmanned tanks, controlled from above by helicopters or even from a base behind. The space and systems saved in not carrying a live crew would make for heavier guns, more ammunition, more computers.

Radars in forward positions or in reconnaissance planes now relay enemy positions directly to computers in guns and rocket launchers, which automatically target them. In future wars, aircraft might sprinkle tiny, cheap, and mobile noise, light, radio, magnetic, and seismic detectors all over a battlefield. Commanders could then have a soldier’s view, a tank’s view, a pilot’s view, and a satellite view of a battle as it happens. What could be more advantageous in battle than having detailed information about the enemy’s formations and movements? And this is all made possible with the ever-increasing speed, power, and miniaturisation of computers.

The stealth, precision, destructiveness, high cost, and the growing sophistication of computerised weapons is making wars briefer, more expensive, more frenetic, and more ferocious. Decisions have to be quick and the situation favours those who can field more and smarter weapons at the very outset, since there is no longer enough time for any but a few nations to build new weapons in time to use them. In Falkland War, for example, Argentina had only five French Exocet missiles. These did sink two major British ships but once the five had been fired, there were none left.

Technologically advanced nations, who can make and improve smart weapons easily, are simply pole-vaulting ahead of others. Of course, nations with cash can acquire some of these weapons. But buying has its own catch. It’s now possible for weapon sellers to programme invisible safeguards into their weapons’ software so that they can’t be used against the seller nations. Buyers may only become aware of the failsafes when they go to war and watch their expensive acquisitions blow up.

As the target selectivity of smart weapons improves, the value of tactical nuclear weapons decreases, since precision weapons can be just as effective. There is no point nuking masses of tanks when conventional weapons are selective enough to do the job. High explosives are cheaper and safer than nuclear weapons, both militarily and politically.

The greatest change in the past few decades has been in the speed of weapon improvement. Because computers control everything in sight, a weapon’s usefulness is determined not just by its physical characteristics, but also by the capabilities of its computer programme. Today’s Patriot missile is essentially the same it was in the 1980s, but its software has been significantly enhanced through several upgrades.

The shift towards software upgradation has another consequence. Now the time required to design, prototype, manufacture, and deploy new weapons can be cut down to a year, even less. Previously this process took a decade or more. This gives an enormous edge to the most technologically advanced and adaptable nations.

There was this gross disparity in training, weapons and surveillance between the American and the Iraqi forces, as displayed in the Gulf War. Computerised weaponry calls for a much higher level of education, skills, and training in its combatants.

Above all, there is the astronomical cost of some new weapons. A single American stealth bomber costs hundreds of millions. And that country’s newest attack submarine is billed at 2,100 million dollars. Such enormous quantities of money give rich nations a significant military edge.

It is a scenario evidently unpromising to many a developing nation. There is no choice but to move to more and yet more dependence on smarter and faster weapons, and advanced computation and communication systems. This in turn means generating enough resources to acquire accessible weaponry and to keep abreast of the explosive pace of computer technology.

Versatile application of advanced materials

by Radhakrishna Rao

OVER the last two decades rapid advances in industrial processes have resulted in the evolution of a whole new range of advanced materials with a wide ranging applications. What’s more, even such ancient materials as ceramics have been given a potentially versatile dimension; the new high strength ceramics — which is a collective term for a class of materials in use for centuries — evolved in early 1990s is being tested for its use in gas turbines on a large scale. It is surmised that ceramic turbine components would have considerable economic and ecological advantage in aerospace and power engineering applications. Perhaps the most positive aspect of going in for the improved ceramic materials is the scope it offers for fuel saving by up to 20 per cent.

Like other composite materials, high performance ceramics display properties such as lightness, fatigue resistance and slower corrosion. No wonder, high performance carbon composites are today the most favoured material to build aircraft and spaceship bodies as well the stages of a carrier rocket. Similarly, the heat shields of strategic missiles are made of glass phenolic or asbestos phenolic composites. Today Kevlar epoxy composites, the production technology of which has been perfected in India’s space facilities and defence labs, are widely used in the missile and launch vehicle programmes. Significantly, the potential of composites in increasing the fuel economy by reducing the weight of vehicles has stimulated remarkable interest in automobile and transportation sectors.

In Europe composite materials are widely used in the fabrication of tank wagons, tanks, vessels pipes, ducts etc.

Aluminium glass composites are made use of in structural application in the form of rods, channels and angles . Similarly, polymer impregnates are used on a large scale for sewer pipes, tunnel linings, manholes, pavement patching and strengthening of bridges.

The poly vinyl chloride (PVC), which has been around for 60 years now, is rapidly emerging as an eco-friendly substitute to plastic which has attracted the ire of eco activists all over the world. PVC, which is a polymer, is used widely in medicare, packaging, water supply, transportation and building industries. In mid-1990s the wroldwide production and consumption of PVC was estimated at 21-million tonnes per annum.

Perhaps, the most exciting application of new composites lies in medical science and health care. New generation carbon fibre composites developed for aerospace applications are being exploited for developing a range of orthopaedic implants. The present generation metallic implants have many drawbacks and are by no means an ideal substitute. Carbon fibre implants can be structured in such a way as to improve resistance to fatigue than metal and they are sufficiently elastic to allow some movement, thereby encouraging the formation of bridging bone-tissue and accelerating the healing time.

Right now, Britain leads the field in the exploitation of carbon fibre composites for orthopaedic implants. Bio-engineer Dr John Bradely and his team at Orthodesign at Christ Church have successfully produced carbon fibre forearm, tibial and femoral fracture plates and cementless artificial hips. So far, there have been no reports of deep or superficial infections, implant failures and adverse clinical reaction to the carbon fibre. Carbon fibre hip replacements are giving new hope to young sufferers because there seems to be no limit to their life.

A synthetic bone developed by British scientists promises longer life than current artificial implants. The next anticipated use of new bone material is for replacing facial bones after accidents or disease such as cancer. But the substances developed with the help of government funding at Queen Mary and West Field College, London could eventually be used throughout the body. According to Prof William Bonfield, a material technology specialist, "there is no problem of rejection with new composite material implants which could be used to replace any bone in the body."

The high performance composite materials promise to improve the quality of human life by revolutionising sectors such as medical treatment, transportation, space exploration and power generation.

Self-medication can be a dangerous proposition. But as far as knowing your body and knowing how to prevent various diseases is concerned, it is rather advisable to be your own doctor. Publications like those brought out by Reader’s Digest and others have been doing yeoman’s service. But there nothing to compare the Net.

One of the finest sites one comes across is www.intelihealth.com. It has such wealth of information on human body and the various ailments that can afflict it. There are separate sections for the problems of children, men, women and old people. Detailed charts complete the picture.

Many preventive measures are detailed. Asthma that I tried out particularly for the sake of a friend yielded great details.

Then there is a searchable drug database, an adult health adviser to provide background on anatomies, diseases and abnormalities. In all, there are more than a million pages on offer.

Since the site is hosted by the medical school at John Hopkins University, Aetna Healthcare and the US National Health Council, the site comprises a trusted source.

« « «

Now that we are on to professional knowledge, let us move on to another topic close to my heart. It is cricket. The interest in the sport is phenomenal. So is the number of books on the subject. Record books are also there galore. But when you need up to date records, you are left in the lurch. In such a situation simply go to www.crickinfo.org. and you will get all the stuff that your will require.

Surprisingly not only there are all the latest details about the Test matches and one-day internationals but also about domestic cricket. And this is true of every country. For example, you can get all the details about Ranji Trophy, Duleep Trophy and Irani Trophy.

It feels nice to know that an Indian, Dr Badri Seshadri, has played a big role in developing this site, along with several people from other countries. Interestingly, among the persons involved in developing the site is British music icon Mick Jagger.

« « «

And here is something for the entire family. The website www.happyfamilies.com. allows you to take a humorous look at family life. It is said that children are the best jokers. This site lets you read the one-liners submitted by hundreds of parents and you can also contribute your own darling’s gems.

And the darling need not be your son or the daughter alone. There is a section for detailing the idiosyncrasies of your hubby or the wife also. The entries already there are endless, and hilarious.

Your can also send e-mail greetings.

« « «

And in the end, details about a site which is not there. Some weeks ago, there was a report in the media that an Indian entrepreneur has developed a software through which letters etc could be written in Indian languages even on a standard English keyboard. Yours truly, like many others, tried to log on to www.bharatvarsh.org. for a free download of the software but it was just not accessible. Many others have a similar story to tell. If you have somehow succeeded, do tell us. Happy surfing.

Jupiter’s moon has oceans?

Astronomers say they have found even more evidence that Jupiter’s moon Europa and perhaps a second moon, Callisto, have liquid oceans under their icy crusts, reports Reuter.

They said the Galileo spacecraft that has been orbiting Jupiter since 1995 had picked up data showing Europa and Callisto disturbed the planet’s magnetic fields. Since neither moon has a magnetic field of its own, the effect is puzzling.

One good explanation, Krishan Khurana and colleagues from the University of California in Los Angeles said in "Nature", is that liquid salty oceans are sloshing around under the ice, causing the formation of electromagnetic fields.

Scientists believe there is a chance life may exist or may once have existed in such subsurface oceans.

"One of the conditions which must be fulfilled for the origin of life is fulfilled on these satellites," Fritz Neubauer, a geophysicist of the University of Koln in Germany, said.Neubauer agrees with Khurana that the likeliest explanation for the electromagnetic induction was liquid water. The Galileo data supports geological evidence of underground water on Europa.

Electromagnetic induction techniques are important tools for geophysicists,Neubauer said. An underground ocean on Europa would not be unexpected, but one on Callisto would be complete surprise. — PTI

1. A 62-year-old Ladakhi man has devised a technique for making "artificial glaciers" near villages in winter and then using water from these glaciers during March-April for sowing crops. Name this rustic scientist, whose innovation is considered to have no parallel in the world.

2. An institute in the USA has designed a smart T-shirt which can provide tele-information about the health of a soldier in battlefield hit by a bullet. What is such a shirt made of?

3. A US scientist has developed a revolutionary immunisation technique by which genetically vaccinated fruits and vegetables would be used for protection against polio, cholera or other diseases. A common fruit and a common vegetable have been found to be most suitable for this purpose. Name these two.

4. Of late there has been a drastic change in the weather and rain patterns throughout the world leading to natural disasters and upsetting of schedule of crops. To which effect is this change attributed?

5. An year of a planet of our solar system is equal to 225 earth days whereas its day is equal to 243 earth days. Name this planet which is about the same size as earth.

6. The prolonged use of this "dal" (pulse), mostly eaten by poor people because of its easy availability and low price, can lead to nervous debility and paralysis. Name this dal. Which substance is there in this dal that causes these diseases?

7.Which is the main ingredient of paper that is obtained from plant and wood pulp for manufacturing paper?

8. Light takes 500 seconds to reach the earth from the sun. How much time does it take to reach the earth from the moon?

9. This plant originally from tropical America was brought to Calcutta in 1809 as an ornamental plant. With the passage of time its seeds spread throughout the country and now it covers vast tracts of land in India. Name this plant invader which bears small yellow flowers.

10. This National Park is located in a cold desert area at a height of about 5,000 metres. The park is especially renowned for protection of endangered snow-leopard and is a home to rare fauna like ibex, red fox, snow cock, bearded vulture, golden eagle, etc. Name this park. Where is it located?

Answers

1. Chewang Norphel.
2. Optical fibres and sensors.
3. Banana and potato.
4. Global warming.
5. Venus.
6. Kesari dal; Beta oxylallanium.
7. Cellulose, a natural polymer.
8. 1.3 seconds.
9. Lantana.
10. Pin valley National Park located in Spiti sub-division of Lahaul Spiti district of Himachal Pradesh.

All-terrain wheelchair

Soon wheelchairs may provide more than basic mobility. A new kind of wheelchair for the disabled has been designed by a US scientist that makes navigation through previously inaccessible areas like soft lawns and stairways possible.

The wheelchair, with robotic arms and mechanical climbing gear attached to its sides, has been designed by Vijay Kumar of the University of Pennsylvania, reports Discover.

The computer-controlled arms can pull the chair up and over obstacles such as a stair or a curb. When the chair returns to ground level, the arms fold out of the way keeping the advantages of wheels.

The centre of gravity of a standard wheelchair is too high — it can tip during climbing manoeuvres. Kumar, therefore, began with a regular plastic office seat, removed its legs and converted it into a wheelchair that is significantly wider and lower than normal.

A future version of the device will have a suspension that would always keep the seat level even while the chair is climbing, the report says.

Photoluminescent LCD

A new photoluminescent liquid crystal display (PL-LCD) technology has been developed by British researchers that gives the same contrast, brightness and colour at all viewing angles in television screen and computer monitors — a privilege earlier offered only by cathode ray tubes (CRTs).

CRTs dominate the displays market due to low price coupled with unrivalled visual performance for large screen applications. LCDs currently dominate the Flat Panel Displays (FPD) market as they provide for lowest-cost solution.

To overcome these limitations researchers of Screen Technology Company and Cambridge University have jointly developed the PL-LCD technology that will enable conventional low-cost passive matrix LCDs (PM-LCDs) to meet the specifications required to compete with CRTs, reports Electronic Engineering.

PM-LCDs, though low in cost, are much restricted in performance.

The main performance limitation of LCDs is the restricted viewing angle, familiar to users of lap tops and notebook computers, which arises from the anisotropic optical properties of liquid crystal materials that are fundamental to the optical effects used. The contrast, brightness and colour of even the best of current LCDs (active matrix) LCDs vary considerably with viewing angles.

PL-LCDs consist of a narrow band, spatially directed, near ultra-violet (UV) backlight, a liquid crystal display modulator and a screen of a photoluminescent material phosphor screen that converts part of the absorbed primary energy into emitted luminescent radiation.

Welding wounds

U.S. researchers have come up with a new kind of laser surgery that uses molecules to stitch together wounds.

Instead of using traditional sutures, the surgery allows doctors to instantly weld injured muscles, tendons and ligaments without the use of heat.

The process, developed by researchers at Baylor Research Institute in Dallas, requires a special kind of dye called photochemical dye and a blast of blue laser light, reports Discover.

The key element in this particular healing technique is a seemingly ordinary chemical descended from a group of dyes called naphthalimides which are commonly used in the laboratory to stain cells yellow so that researchers can follow their movement. Baylor researchers are working with a variant of naphthalimide that is ideal for healing, not just for staining.

In its basic form, naphthalimide is a ringlike molecule. Two such rings are joined with a molecular chain and the resulting dye so engineered that each ring reacts only in the presence of blue light.

The molecule absorbs the light energy, is excited to a higher energy state, and then chemically reacts with amino acids of protein, says Millard Judy, a biophysicist at the institute. This reactivity is the secret to naphthalimide’s medical utility, he says.

Slim TV

A U.S. researcher has reportedly found a way to reduce the depth of cathode-ray tube (CRT) in big television sets which are often as deep as their widths.

In the upcoming high-definition television (TV) sets with big screens, use of conventional CRT is a problem due to high cost and size of the gadget.

Michael Geis, a physicist at Massachusetts Institute of Technology’s (MIT) Lincoln Laboratory, turned to a newer technology called "cold cathodes", which employs an electric field rather than heat to pull out electrons from a metal, reports Discover.

By modifying metal-diamond junction in cold cathodes, Geis’s team achieved their target.

Companies have laboured for years to develop slimmer or flat-screen television.