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The magic of Maya Dirty bombs: the silent killers BIS code on earthquakes
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The magic of Maya
From cartoon strips to educational videos, commercials, music videos, interactive video games and children programs, Maya lets you play the role of director, actor, set designer and cinematographer as you build, render and animate digital characters and scenes. Maya is the tool of choice for digital content creators, whether it's a one-man shop or a full-fledged animation studio. Maya adds to the quality and realism of graphics. That's why film and video artists, game developers, visualisation professionals, web and print designers turn to Maya to take their work to the next level. Maya is a 3D modelling, rendering, animation, and paint software package that delivers all the tools and features 3D artists need to produce animation and visual effects on the computer. With Maya a 3D artiste could let his imagination fly free and leave the rest to the tool. Such is the power of Maya; even novices, with a good concepts background, can lap it up easily. Movies made in Maya include The Mummy, The Mummy Returns, George of the Jungle, The Fifth Element, Final Fantasy, The Hollow Man, The X-Man, Anaconda, Stuart Little, Shrek, Sindbad, Pandavas, Starship Trooper, Lake Placid, The Phantom Menace, Spiderman, Harry Potter, Jurassic Park 3, Star Wars, Lord of the Rings, Ice Age and more. Add to this scientific features and laws of physics controls, wherein the objects could be controlled very precisely and naturally for its motion. To add visual realism, Maya has volumetric lighting and real world atmospheric effects like fog. The motion builder is one of the components of Maya and is used for 3D games development. Some of the top animation developers for Hollywood like Industrial Light and Magic, Dreamworks etc and some of the greatest blockbusters like Mummy, Star Wars, Perfect Storm have benefited from Maya. Some Sony Playstation games have used Maya to a great extent. |
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Dirty bombs: the silent killers A
dirty bomb is an explosive device manufactured to spread harmful radioactive material over a wide range. It is different from the nuclear bomb, in the sense that its primary goal is destructive power, and not radiation damage. A dirty bomb contains the mixture of the explosive TNT (trinitrotoluene) and the radioactive material. The basic goal of the dirty bomb is to spread radioactive material in the form of a dust cloud, over a large geographical area. The radioactive material generates ionising radiations, which include alpha particals, beta particles, X-rays and gamma rays. These radiations possess power to remove an orbital electron off an atom. This results in an imbalance between the positively charged protons and negatively charged electrons, thereby converting an atom into an ion. The free electrons collide with other atoms to produce more ions. These ions affect the human body leading to unhealthy chemical reactions inside the cells. The charge can break the DNA chains and a cell with a broken DNA strand will die or develop mutation. This activity can result into various dreadful diseases like cancer. In a dirty bomb, the ionising radiation is generated from radioactive isotops, which are the atoms that decay over time. The radioactive decay releases energy in the form of ionising radiation. The design and manufacturing range of a dirty bomb is dependent on the type and quantity of radioactive material. The dynamite and TNT are reasonably accessible whereas the radioactive material is not easily available. Certain hospitals make use of radioactive material in the research areas of nuclear medicine. The amount of damage caused by a dirty bomb is unpredictable. The immediate deaths would be due to explosion and not the radiation. The prolonged exposure can cause havoc. Till date there is no precedence of dirty bomb attack. Researchers converge to an opinion that a dirty bomb has disruptive rather than destructive effect. The fear of anthrax still haunts the Americans. The prolonged exposure of human body to the X-ray machine can also cause cancer. A dirty bomb will definitely increase the radiation level exposure above normal levels. Instead of instant killing the result will be silent killing over the years. |
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BIS code on earthquakes Structural
designs of buildings, flyovers, tall towers, chimneys, dams, power plants or other structures are evolved after taking into account different combinations of loads such as dead loads, live loads, wind loads, earthquake forces, earth pressures, wave loads etc and the most critical load combination is chosen for design calculations. The values of these loads are worked out on the basis of past experiences and recurring intervals of natural vagaries like floods, earthquakes, cyclones and wind storms. As and when we experience a force higher in magnitude than that assumed in our designs, we tend to revise our codal instructions and newly experienced forces are taken into account. Bhuj earthquake of 2001 left the country and its designers stunned and made them put their heads together and review the seismic division of the country and codal instructions to build earthquake-resistant structures. BIS code IS 1893, laying criteria for earthquake resistant design of structures has, therefore, been revised and is in force now. All structural designers are therefore required to follow IS 1893-2002 now as the revised edition carries significant changes. Keeping in view the research carried out and study of earthquakes that occurred during 1984-2002, IS 1893-2002 has been split into five parts. Provisions of Part I are applicable to all structures. This code has therefore been released. Part II to V are still under finalisation. In the revised code, significant changes have been made as explained below : 1. Revised seismic zoning of India : Earlier the country had been divided into five zones with Zone I least prone and Zone V most prone to earthquakes. Zone I has now been merged with Zone II and now there exist only four zones i.e. Zone II to Zone V. The towns falling at the boundary of zone demarcation lines are to be considered to be in higher zone. 2. Seismic zone factors : A significant change made now is the introduction of seismic Zone Factor ‘Z’ based on Maximum Considered Earthquake and service life of structures and elimination of ‘Basic Horizontal Seismic Coefficient’ a0. For Chandigarh, falling in Zone IV, the coefficient used earlier was 0.05 while the zone factor now to be considered is 0.24. Similarly, for Bhuj, falling in Zone V, value of a0 was 0.08 while that of Z now is 0.36. The Zone Factors now incorporated in the code are more realistic. 3. Response reduction factor : Performance Factor “K” existing earlier has been dropped and Response Reduction Factor ‘R’ has been introduced. More strong is the building frame system, more is the value of ‘R’. Value of ‘R’ is least for a masonry structure and highest for steel or special RCC buildings. 4. Soil Foundation system coefficient dropped : Soil Foundation system coefficient ‘ß’ has been dropped and a special clause has been added to restrict the use of foundations vulnerable to differential settlement in severe seismic zones. 5. Torsional Eccentricity: Special attention has been paid to torsional eccentricity occurring in buildings with irregular plans as such buildings get severally damaged during earthquakes. The values of torsional eccentricity have been revised upwards. 6. Design Method : The method of design for earthquake resistance has also been modified. a0 and ah have been replaced by a new ‘Design Horizontal Seismic Coefficient’ Ah. The formula for calculation of Ah includes the Zone Factor ‘Z’ and Response Reduction Factor ‘R’ in it instead of a0. 7. Soft storey concept : Due to increased use of soft storeys in buildings such as provision of open parking space below multi-storeyed flats, design criteria to be used for soft storeys has been provided. 8.Height criteria: Earlier all buildings falling in Zone III and above 40 metres height required dynamic analysis. Now only irregular buildings of this zone require this analysis. For regular buildings, the height criteria has been revised to 90 metres. 9.Shear wall concept : Provisions of IS 13920 for Ductile detailing of RCC structures are to be adopted now for all such structures located in Zone III, IV and V. This code includes the sheer wall concept which is the best method to avoid collapse of structures during earthquakes. As is clear from the above, the new code includes significant changes which need to be used not only to design all new structures but also for checking the existing structures for their strengthening wherever required, so as to resist any failures on occurrence of earthquakes. |
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Fresh face of King Tut Besides providing boundless information on the health and possible cause of death of the legendary young king, the data could paint a fresh portrait of Tut’s face - the first bust of Tut ever created from 3-D CT scans. Under the leadership of Zahi Hawass, secretary general of Egypt’s Supreme Council of Antiquities, National Geographic has used the CT data to show the world how Tut looked the day he died, some 3,300 years ago. The process involved forensic artists and physical anthropologists from two countries and created two independently made busts of Tut. Still, despite the solid scientific information used, it is impossible to know for certain everything about how King Tut looked - the shape of the top of his nose, the shape of his ears, the color of his eyes and skin — as they are not determined by the shape and proportions of his skull. Geyser microbes A ‘’weird’’ community of microbes living in a hot, acid geyser in Wyoming’s Yellowstone Park may help scientists know what to look for in seeking life on Mars and elsewhere in space, researchers said. They found the new species of algae and bacteria living in a green-colored layer of sandstone in Yellowstone’s Norris Geyser Basin. It was not a place where one would normally expect to find life thriving, said Norman Pace of the University of Colorado at Boulder’s biology department and Center for Astrobiology.
— Reuters Hip surgery There is good news for those suffering from hip arthritis and hip infections. A new hip resurfacing technique helps patients lead a better life by restoring normal limb movements. The new technique allows surgeons to replace the diseased human hip with artificial limplants, ensuring near normal movements and functions, leading orthopaedic surgeons said here.
— PTI
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THIS
UNIVERSE Q We do not get snow in the plains even when the minimum temperature during winter can touch zero degrees. On the other hand we do get hail quite often even when it is not so cold on the ground. Why hail is possible in the plains and not snow? A Snow is often associated with a relatively well-behaved, serene, cold atmosphere. Water vapour condenses into tiny crystals of ice that congregate and descend as fluffy flakes. If the distance of descent is large and the flakes encounter warm air on the way down the snow melts and all we get is rain. That is what happens on the plains in our country. If the temperature in the plains is less than freezing point on a continuous basis then snow does come down to surface, as in temperate regions and higher latitudes during winter. Hailstorms are usually associated with restless conditions of the atmosphere, meeting of warm moist air masses with cold fronts, fast convection and even lightning. During convection tiny water droplets ascending into colder air at higher altitude are super-cooled to below the freezing point. They form nuclei for accretion of moisture forming layer after layer of ice. The tiny ice balls are pushed around, even upwards, all the time collecting more mass, till they become heavy and begin to descend. These balls of ice are better protected from the heat of the lower atmosphere than snowflakes because of their compactness and smaller surface area. (You might remember that a sphere has the lowest surface area for a given mass.) This is the reason that we can get hailstorms in our plains and not snowstorms. Hailstones survive their fast trip through the lower atmosphere. Q Some years ago a man from Tamil Nadu had shown that he could run cars and other vehicles with water turned into petrol with some herbs. This was demonstrated in front of the Prime Minister and also shown on Doordarshan. Why does the government not utilise his invention and where has that man gone? A The reason is that that man was shown to be a cheat or a trickster who had petrol in the hollow ladle he used for stirring his brew of water and herbs. It is shameful that he could dupe so many people, even some with scientific credentials for so long. Our society is very vulnerable in this regard. Under some conditions we are extremely gullible. You might remember the hysteria that gripped the country some years ago when Lord Ganesh was shown to be drinking milk! That phenomenon could be easily explained in scientific terms. Stone or marble statues cannot drink milk and that only with the help of a flat spoon as most enthusiasts and people caught in that hysteria demonstrated. |
Maya has unlimited features. It has a great modeler where a 3D modeler can create models using polygons, NURBS and other advanced features. These objects would look exactly real-life; a carefully modeled human being or a dinosaur would look like a real one. The unlimited bundle of this software has features for character design and powerful animation features, where one could make the objects created virtually dance and look like real ones. The ability to animate or move individual areas of an object makes Maya very special.
The scientific breakthrough: Some 1,700 high-resolution Siemens CT-scanner images of the world’s most famous mummy — King Tutankhamun. The opportunity: