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| SCIENCE TRIBUNE | Thursday, October 3, 2002, Chandigarh, India |
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Remote-controlled guns EARTHQUAKE TIPS DNA testing of
Columbus’ tomb
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Remote-controlled guns THE remotely triggered infantry weapons like guns and rifles are the next step in the revolution in defence technology. Soldiers and others, whose normal duties now place them in the line of fire, could soon be protected and even have their shooting abilities improved by new weapons systems that let them operate the weapons remotely. One remotely operated gun system, developed by Dr Graham Hawkes, of Precision Remotes Inc. based at Point Richmond, California, and is being currently tested by the American Army. It is light enough for a single soldier to carry to the front line, and set up. It can also be positioned at stationary sites like buildings. In another system, gimbals hold the guns level so they could be fired remotely from a moving jeep. Eventually, remote guns could even be sent into battle, after mounting them on the roof of remote-controlled jeeps. All these weapons, of course, rely on people to operate them. They are not robots because the guns will not fire unless told to do so by an operator, near the site through a computer system called “Telepresence.” Telepresence is an electronic imaging system that shows the soldier what a remote site looks like so that he feels that he is physically present at the site. The designers are trying to keep the human brain and judgement involved in the operations. Applications for such systems are numerous. Among those under consideration is protection of army installations, ammunition factories, army camps and fixed places such as embassy buildings and nuclear plants. The need to protect them from terrorists has grown more acutely in recent months. Remote weapons would let users take on potential attackers from within a protected area with a remote controller. In some situations, there might be less need to fire preemptively, as the soldier would not be on the line. In 1997, the company began developing a remotely operated gun on its own. Now available. the system can control standard automatic weapons such as a machine gun, as well as multi-kilometre range weapons. The system can be operated by just one person and its controlled much like a TV game using, an electrically connected handheld control with joystick, viewfinder, and firing button. Users can play between a wide-angle survey lens and a riflescope, complete with crosshairs, which is used for aiming and firing. Aim is improved through mechanisms such as blinking lights, which indicate how far the gun has moved, and an audio feed, which gives operators a feel for gun position by letting them hear its movement. A wireless version is also under development. The company claims that, under ideal conditions, the remotely controlled gun is as accurate as the same gun fired by a soldier. For security purposes, the system could be housed in a bulletproof box that would be opened remotely only when needed. One system under development involves connection of a number of guns by fibreoptic cables. This would enable one soldier to monitor and operate several guns, decreasing the number of soldiers needed to provide adequate security. The system could be switched off, if for instance, someone shot out its riflescope. That would be a relatively small loss compared to a soldier’s life. The possibilities for other advances are nearly limitless. Technologies such as night or thermal vision could easily be integrated into the system. Future developments could include the ability to automatically track a target once it has been identified, or to identify the person, perhaps by using a transponder added to soldier’s uniforms. The company is also developing a version suited to the needs of police. A logical longer-term extension for remote controlled guns will be mounting them on remote controlled battle tanks also under development. Such weapons could be on the battlefield in a few years time. |
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EARTHQUAKE
TIPS THE behaviour of a building during earthquakes depends critically on its overall shape, size and geometry, in addition to how the earthquake forces are carried to the ground. Hence, at the planning stage itself, architects and structural engineers must work together to ensure that the unfavourable features are avoided and a good building configuration is chosen. The importance of the configuration of a building was aptly summarised by Late Henry Degenkolb, a noted Earthquake Engineer of USA, as: “If we have a poor configuration to start with, all the engineer can do is to provide a band-aid-improve a basically poor solution as best as he can. Conversely, if we start-off with a good configuration and reasonable framing system, even a poor engineer cannot harm its ultimate performance too much.” In general, buildings with simple geometry in plan (Figure 2a) have performed well during strong earthquakes. Buildings with re-entrant corners, like those U, V, H and + shaped in plan (Figure 2b), have sustained significant damage. Many times, the bad effects of these interior corners in the plan of buildings are avoided by making the buildings in two parts. For example, an L-shaped plan can be broken up into two rectangular plan shapes using a separation joint at the junction (Figure 2c). Often, the plan is simple, but the columns/walls are not equally distributed in plan. Buildings with such features tend to twist during earthquake shaking. Authored by
C. V. R. Murty (Indian Institute of Technology, Kanpur) for Building Materials and Technology Promotion Council, New Delhi. |
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DNA testing of Columbus’ tomb WHO was Christopher Columbus — an Italian weaver’s son or a Spanish aristocrat? Where does he lie buried — in the southern Spanish city of Seville or in the Dominican Republic? A group of Spanish scientists intends to use DNA testing to solve the old enigmas surrounding the birth and burial of the discoverer of the New World. Two places currently claim to watch over Columbus’ remains: the vast gothic cathedral of Seville and a towering monument known as the Columbus Lighthouse in the Dominican capital Santo Domingo. If the Spanish Catholic church and the Dominican authorities grant permission, both sets of bones will shortly be dug up to extract DNA strands and to compare them with DNA from Columbus’ brother Diego and son Hernando. It is generally believed that Christopher Columbus was born in 1451 to the family of a wool weaver in the Italian port of Genoa — yet the admiral is not known to have visited Genoa later in life, and always wrote in Spanish.
DPA |
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NEW PRODUCTS & DISCOVERIES Laughing gas meets nintendo Designed to reduce the anxiety of children during medical procedures, the PediSedate headset plays music or sounds from a Nintendo Game Boy while monitoring respiratory function and distributing nitrous oxide. The headset is now undergoing clinical trials. Nanotechnology has its risks It’s supposed to make computers small enough to implant into a wrist and supply materials that strengthen and lighten bridges and airplanes. It might even cure cancer. But some environmentalists fear that nanotechnology, the fast-advancing science of manipulating materials at the molecular scale, may create contaminants whose tiny size makes them ultra-hazardous. “If they get in the bloodstream or into ground water, even if the nanoparticles themselves aren’t dangerous, they could react with other things, that are harmful,” said Kathy Jo Wetter, a researcher with the ETC group, an environmental organisation that also opposes genetically modified crops. Scientists say such fears consist mainly of speculation. Nanotechnology, they say, involves well-known materials such as carbon, zinc and gold — both toxic and benign. New tools simply let researchers alter those materials at the atomic level, where the particles are measured in nanometers, or billionths of a meter. “It may have some unexpected consequences. Some could be toxic,” said Mihail Roco, the National Science Foundation’s senior adviser on nanotechnology. “But this happens with larger particles and in other industries. The risks are very small in comparison with the benefits.”
AP Water framework directive Governments across Europe may be forced to revolutionise farming in their countries in the face of a new European Union directive to dramatically raise the quality of river water, scientists have said. The water Framework Directive, which must be transposed into national law across the 15-nation bloc by the end of 2003, sets tough new limits on the level of pollutants permitted in rivers and ground water that will force land use changes, they said yesterday. “Farmers are going to have to retreat,” Simon Harrison of Ireland’s University College Cork told reporters at the British Association for the Advancement of Science’s annual festival being held at the University of Leicester. Penny Johnes of the University of Reading said watercourses across Britain were far more heavily polluted than indicated by official government statistics which tended to paint an unrealistically rosy picture of water quality. “In the last decade of the 20th century, 95 per cent of British fresh water was polluted by nutrients — most of which was from diffuse sources — in other words farming,” she said. “British waters are highly degraded in terms of nutrient pollution. We need to change land use,” Johnes added. She said point source pollution from factories or spills was fairly well under control, but that leaching from farmland had barely been touched because it was far more complex and difficult to tackle. In many instances the problem was due to inappropriate or overly intensive land use that either led to local flooding of towns and villages because flood plains had been drained and rivers diverted or meant heavy run-off of pollutants.
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SCIENCE
& TECHNOLOGY CROSSWORD
Across: 1. Plates joining to form a layer of rocks called Earth’s crust. 8. Keep the parking lot so to avoid skidding of vehicles. 9. Tide is known as this when high water is at its lowest level of the year. 11. A book showing physical features of various countries. 12. Exert steady force. 15. An organization supporting electronic sales and providing warehousing facilities for exports. 16. Short for Institution of Engineers (India ). 17. Antenna used to improve TV reception. 18. An enclosure to treat patients of rheumatoid arthritis by application of controlled magnetic field. 19. A scheme of postal department to carry articles by air without discharge. 21. A statue without limbs or head. 23. Symbol for Lanthanum. 25. Expansion directly proportional to original length and rise in temperature. 26. Symbol for Phosphorous. 27. Symbol for Neon. 28. Premier atomic research center of India situated at Trombay. Down: 1. These climates are hot with average noon temperature varying by 2 degree Celsius only. 2. The oldest script of the world invented by Sumerians of Mesopotamia. 3. Short for Turbo-generator. 4. Short for hydroxide. 5. Whole number. 6. Zero of this scale corresponds to 273 degree of Kelvin. 7. Magnesium Sulphate salt. 10. A 20th century invention to computerize transport services (known in abbreviation). 13. …….. sensing is the technique to gather information without actual contact with the object under study. 14. Rhythmical contraction of the heart. 20. Energy that needs to be exploited now to the maximum. 22. A new concept in computers having seven functions and proposed by ISO. 24. A segment of a circle. Solution to last week’s
Crossword:
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A desire to create an aesthetic and functionally efficient structure drives architects to conceive wonderful and imaginative structures. Sometimes the shape of the building catches the eye of the visitor, sometimes the structural system appeals, and in other occasions both shape and structural system work together to make the structure a marvel. However, each of these choices of shapes and structure has significant bearing on the performance of the building during strong earthquakes. The wide range of structural damages observed during past earthquakes across the world is very educative in identifying structural configurations that are desirable versus those which must be avoided.
In tall buildings with large height-to-base size ratio (Figure 1a), the horizontal movement of the floors during ground shaking is large. In short but very long buildings (Figure 1b), the damaging effects during earthquake shaking are many. And, in buildings with large plan area like warehouses (Figure 1c), the horizontal seismic forces can be excessive to be carried by columns and walls.
