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MCQ-> In a modern computer, electronic and magnetic storage technologies play complementary roles. Electronic memory chips are fast but volatile (their contents are lost when the computer is unplugged). Magnetic tapes and hard disks are slower, but have the advantage that they are non-volatile, so that they can be used to store software and documents even when the power is off.In laboratories around the world, however, researchers are hoping to achieve the best of both worlds. They are trying to build magnetic memory chips that could be used in place of today’s electronics. These magnetic memories would be nonvolatile; but they would also he faster, would consume less power, and would be able to stand up to hazardous environments more easily. Such chips would have obvious applications in storage cards for digital cameras and music- players; they would enable handheld and laptop computers to boot up more quickly and to operate for longer; they would allow desktop computers to run faster; they would doubtless have military and space-faring advantages too. But although the theory behind them looks solid, there are tricky practical problems and need to be overcome.Two different approaches, based on different magnetic phenomena, are being pursued. The first, being investigated by Gary Prinz and his colleagues at the Naval Research Laboratory (NRL) in Washington, D.c), exploits the fact that the electrical resistance of some materials changes in the presence of magnetic field— a phenomenon known as magneto- resistance. For some multi-layered materials this effect is particularly powerful and is, accordingly, called “giant” magneto-resistance (GMR). Since 1997, the exploitation of GMR has made cheap multi-gigabyte hard disks commonplace. The magnetic orientations of the magnetised spots on the surface of a spinning disk are detected by measuring the changes they induce in the resistance of a tiny sensor. This technique is so sensitive that it means the spots can be made smaller and packed closer together than was previously possible, thus increasing the capacity and reducing the size and cost of a disk drive. Dr. Prinz and his colleagues are now exploiting the same phenomenon on the surface of memory chips, rather spinning disks. In a conventional memory chip, each binary digit (bit) of data is represented using a capacitor-reservoir of electrical charge that is either empty or fill -to represent a zero or a one. In the NRL’s magnetic design, by contrast, each bit is stored in a magnetic element in the form of a vertical pillar of magnetisable material. A matrix of wires passing above and below the elements allows each to be magnetised, either clockwise or anti-clockwise, to represent zero or one. Another set of wires allows current to pass through any particular element. By measuring an element’s resistance you can determine its magnetic orientation, and hence whether it is storing a zero or a one. Since the elements retain their magnetic orientation even when the power is off, the result is non-volatile memory. Unlike the elements of an electronic memory, a magnetic memory’s elements are not easily disrupted by radiation. And compared with electronic memories, whose capacitors need constant topping up, magnetic memories are simpler and consume less power. The NRL researchers plan to commercialise their device through a company called Non-V olatile Electronics, which recently began work on the necessary processing and fabrication techniques. But it will be some years before the first chips roll off the production line.Most attention in the field in focused on an alternative approach based on magnetic tunnel-junctions (MTJs), which are being investigated by researchers at chipmakers such as IBM, Motorola, Siemens and Hewlett-Packard. IBM’s research team, led by Stuart Parkin, has already created a 500-element working prototype that operates at 20 times the speed of conventional memory chips and consumes 1% of the power. Each element consists of a sandwich of two layers of magnetisable material separated by a barrier of aluminium oxide just four or five atoms thick. The polarisation of lower magnetisable layer is fixed in one direction, but that of the upper layer can be set (again, by passing a current through a matrix of control wires) either to the left or to the right, to store a zero or a one. The polarisations of the two layers are then either the same or opposite directions.Although the aluminum-oxide barrier is an electrical insulator, it is so thin that electrons are able to jump across it via a quantum-mechanical effect called tunnelling. It turns out that such tunnelling is easier when the two magnetic layers are polarised in the same direction than when they are polarised in opposite directions. So, by measuring the current that flows through the sandwich, it is possible to determine the alignment of the topmost layer, and hence whether it is storing a zero or a one.To build a full-scale memory chip based on MTJs is, however, no easy matter. According to Paulo Freitas, an expert on chip manufacturing at the Technical University of Lisbon, magnetic memory elements will have to become far smaller and more reliable than current prototypes if they are to compete with electronic memory. At the same time, they will have to be sensitive enough to respond when the appropriate wires in the control matrix are switched on, but not so sensitive that they respond when a neighbouring elements is changed. Despite these difficulties, the general consensus is that MTJs are the more promising ideas. Dr. Parkin says his group evaluated the GMR approach and decided not to pursue it, despite the fact that IBM pioneered GMR in hard disks. Dr. Prinz, however, contends that his plan will eventually offer higher storage densities and lower production costs.Not content with shaking up the multi-billion-dollar market for computer memory, some researchers have even more ambitious plans for magnetic computing. In a paper published last month in Science, Russell Cowburn and Mark Well and of Cambridge University outlined research that could form the basis of a magnetic microprocessor — a chip capable of manipulating (rather than merely storing) information magnetically. In place of conducting wires, a magnetic processor would have rows of magnetic dots, each of which could be polarised in one of two directions. Individual bits of information would travel down the rows as magnetic pulses, changing the orientation of the dots as they went. Dr. Cowbum and Dr. Welland have demonstrated how a logic gate (the basic element of a microprocessor) could work in such a scheme. In their experiment, they fed a signal in at one end of the chain of dots and used a second signal to control whether it propagated along the chain.It is, admittedly, a long way from a single logic gate to a full microprocessor, but this was true also when the transistor was first invented. Dr. Cowburn, who is now searching for backers to help commercialise the technology, says he believes it will be at least ten years before the first magnetic microprocessor is constructed. But other researchers in the field agree that such a chip, is the next logical step. Dr. Prinz says that once magnetic memory is sorted out “the target is to go after the logic circuits.” Whether all-magnetic computers will ever be able to compete with other contenders that are jostling to knock electronics off its perch — such as optical, biological and quantum computing — remains to be seen. Dr. Cowburn suggests that the future lies with hybrid machines that use different technologies. But computing with magnetism evidently has an attraction all its own.In developing magnetic memory chips to replace the electronic ones, two alternative research paths are being pursued. These are approaches based on:
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MCQ-> Read the following passage carefully and answer the questions given below it. Certain words/phrases have been printed in bold to help you locate them while answering some of the questions. Once upon a time there was a King of Benaras who was very rich. He had many servants and a beautiful palace with wonderful gardens; he had chariots and a stable full of horses. But his most prized possession was a magnificent elephant called Mahaghiri. She was as tall as two men, and her skin was of the colour of thunder clouds. She had large flapping ears and small, bright eyes and she was very clever. Mahaghiri lived in her own special elephant house and had her own keeper, Rajinder. The King would often visit Mahaghiri to take her some special tit-bit to eat and check that Rajinder was looking after her properly. But Rajinder needed no reminding, for he also loved the elephant dearly, and trusted her completely. Every morning, he would take her down to the river for her bath. Then he would bring her freshly cut grass, leaves and the finest fruits he could find in the market for her breakfast. During the day, he would talk to her and, in the evening, he would play his flute to send her to sleep. One morning, Rajinder arrived as usual with fruit for Mahaghiri’s breakfast. Suddenly, before he knew what was happening, she picked him up with her trunk and threw him out of the stall, breaking his arm. She began to stamp on the ground and trumpet so loudly that it took several strong men all morning to bind her with ropes and chains, When the king heard about what had happened, he was very upset and sent for the doctor to help Rajinder. Then he called for his chief minister. “You must go and see Mahaghiri at once,” he said. “She used to be so kind and gentle, but this morning she threw her keeper out of her stall. I can’t understand it. She must be ill or in pain. Spare no expense in finding a cure.” So the chief minister went to see Mahaghiri. who was still bound firmly with ropes. First he looked at her eyes – they were as clear and bright as usual. Then he felt behind her ears – her temperature was normal. Next he listened to her heart that was fine too – and checked all over for cuts or sores. He could find nothing wrong with her. “Strange,” he thought. “I can find no explanation for her bad behaviour.”But then his eye was caught by something gleaming in the straw. It was a sharp, curved knife, like the ones used by robbers. Could there be a connection? That night, when everyone else had gone to bed, the chief minister returned to the elephant house. There, in the stall next to Mahaghiri’s, sat a band of robbers. “Tonight we’ll burgle the palace,” said the chief. “First, we’ll make a hole in the wall, then we’ll steal the treasure. “But what about the guards?” someone asked. “Don’t tell me you’re still afraid to kill! When will you learn to be a real robber?” From the shadows, the minister could see the elephant, her ears pinned back, listening to every hateful and violent word.”Just as I suspected,” thought the minister. Then he slipped out, bolted the door on the outside so the robbers could not escape, and went immediately to the king.”Your majesty,” he said, “I think I have found the cause of your elephant’s bad behaviour.” As soon as the king heard what the minister had to say, he sent for his guards and had the robbers arrested. “But what about the elephant? How can she be cured?’ he asked. “Well, your majesty, if Mahaghiri became dangerous through being.in the company of those wicked robbers, perhaps she could be cured by being in the company of good people.” “What a brilliant idea!” exclaimed the king. “Let us invite the friendliest, happiest and kindest people in the city to meet in the stall next to the elephant.” “Mahaghiri, the king’s most prized elephant, has been in bad company and has become violent and dangerous,” the minister told his friends. “Will you help her to become her old self again?””Of course,” they replied. “What do you want us to do?” “Just meet in the elephant house every day for the next week. Let her hear how kindly and thoughtfully you speak to each other, and how helpful you are.” So the minister’s friends met in the elephant house as planned. They talked together and enjoyed each other’s company. Sometimes they brought cakes and sweets to share; sometimes their children came and played happily in the straw. All the while, Mahaghiri watched and listened. Gradually, she became calmer. “I think it’s working,” said the minister. “Soon we’ll be able to remove the ropes.” Everyone felt a bit nervous when the day came for Mahaghiri to be untied. The king ordered everyone to wait outside as, very carefully, brave Rajinder began to undo the ropes around her ears and trunk. Next he removed the ropes holding her head. Finally, he loosened the thick chains holding her great feet. Everyone held their breath. What if she was still wild?Mahaghiri looked round shuffling her feet to stretch them. Then she slowly curled her trunk around her keeper’s waist and lifted him high into the air before placing him gently on her back. A great cheer went up. The king was delighted. “Let’s have a picnic to celebrate,” he announced. “Mahaghiri can come too.” What a great afternoon they all had! Mahaghiri bathed in the lake and gave the children rides. It seemed as though she had now become kinder, gentler and even more trustworthy than ever. But Rajinder never forgot what had happened and was always careful to set Mahaghiri a good example by being kind and friendly himself.As per the context of passage, what was the most prized possession of the king of Benaras ?
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MCQ-> Read the passage carefully and answer the questions given at the end of each passage:We now come to the second part of our journey under the sea. The first ended with the moving scene in the coral cemetery which left a deep impression on my mind. I could no longer content myself with the theory which satisfied Conseil. That worthy fellow persisted in seeing in the Commander of the Nautilus one of those unknown servants who returns mankind contempt for indifference. For him, he was a misunderstood genius who, tired of earth’s deceptions, had taken refuge in this inaccessible medium, where he might follow his instincts freely. To my mind, this explains but one side of Captain Nemo’s character. Indeed, the mystery of that last night during which we had been chained in prison, the sleep, and the precaution so violently taken by the Captain of snatching from my eyes the glass I had raised to sweep the horizon, the mortal wound of the man, due to an unaccountable shock of the Nautilus, all put me on a new track. No; Captain Nemo was not satisfied with shunning man. His formidable apparatus not only suited his instinct of freedom, but perhaps also the design of some terrible retaliation. That day, at noon, the second officer came to take the altitude of the sun. I mounted the platform, and watched the operation. As he was taking observations with the sextant, one of the sailors of the Nautilus (the strong man who had accompanied us on our first submarine excursion to the Island of Crespo) came to clean the glasses of the lantern. I examined the fittings of the apparatus, the strength of which was increased a hundredfold by lenticular rings, placed similar to those in a lighthouse, and which projected their brilliance in a horizontal plane. The electric lamp was combined in such a way as to give its most powerful light. Indeed, it was produced in vacuo, which insured both its steadiness and its intensity. This vacuum economized the graphite points between which the luminous arc was developed - an important point of economy for Captain Nemo, who could not easily have replaced them; and under these conditions their waste was imperceptible. When the Nautilus was ready to continue its submarine journey, I went down to the saloon. The panel was closed, and the course marked direct west. We were furrowing the waters of the Indian Ocean, a vast liquid plain, with a surface of 1,200,000,000 of acres, and whose waters are so clear and transparent that any one leaning over them would turn giddy. The Nautilus usually floated between fifty and a hundred fathoms deep. We went on so for some days. To anyone but myself, who had a great love for the sea, the hours would have seemed long and monotonous; but the daily walks on the platform, when I steeped myself in the reviving air of the ocean, the sight of the rich waters through the windows of the saloon, the books in the library, the compiling of my memoirs, took up all my time, and left me not a moment of ennui or weariness. From the 21 st to the 23 rd of January the Nautilus went at the rate of two hundred and fifty leagues in twenty- four hours, being five hundred and forty miles, or twenty-two miles an hour. If we recognized so many different varieties of fish, it was because, attracted by the electric light, they tried to follow us; the greater part, however, were soon distanced by our speed, though some kept their place in the waters of the Nautilus for a time. The morning of the 24 th , we observed Keeling Island, a coral formation, planted with magnificent cocos, and which had been visited by Mr. Darwin and Captain Fitzroy. The Nautilus skirted the shores of this desert island for a little distance. Soon Keeling Island disappeared from the horizon, and our course was directed to the north- west in the direction of the Indian Peninsula. From Keeling Island our course was slower and more variable, often taking us into great depths. Several times they made use of the inclined planes, which certain internal levers placed obliquely to the waterline. I observed that in the upper regions the water was always colder in the high levels than at the surface of the sea. On the 25th of January the ocean was entirely deserted; the Nautilus passed the day on the surface, beating the waves with its powerful screw and making them rebound to a great height. Three parts of this day I spent on the platform. I watched the sea. Nothing on the horizon till about four o’clock then there was a steamer running west on our counter. Her masts were visible for an instant, but she could not see the Nautilus, being too low in the water. I fancied this steamboat belonged to the P.O. Company, which runs from Ceylon to Sydney, touching at King George’s Point and Melbourne. At five o’clock in the evening, before that fleeting twilight which binds night to day in tropical zones, Conseil and I were astonished by a curious spectacle. It was a shoal of Argonauts travelling along on the surface of the ocean. We could count several hundreds. These graceful molluscs moved backwards by means of their locomotive tube, through which they propelled the water already drawn in. Of their eight tentacles, six were elongated, and stretched out floating on the water, whilst the other two, rolled up flat, were spread to the wing like a light sail. I saw their spiral-shaped and fluted shells, which Cuvier justly compares to an elegant skiff. For nearly an hour the Nautilus floated in the midst of this shoal of molluscs. The next day, 26 th of January, we cut the equator at the eighty-second meridian and entered the northern hemisphere. During the day a formidable troop of sharks accompanied us. They were “cestracio philippi” sharks, with brown backs and whitish bellies, armed with eleven rows of teeth, their throat being marked with a large black spot surrounded with white like an eye. There were also some Isabella sharks, with rounded snouts marked with dark spots. These powerful creatures often hurled themselves at the windows of the saloon with such violence as to make us feel very insecure. But the Nautilus, accelerating her speed, easily left the most rapid of them behind.About seven o’clock in the evening, the Nautilus, half- immersed, was sailing in a sea of milk. At first sight the ocean seemed lactified. Was it the effect of the lunar rays? No; for the moon, scarcely two days old, was still lying hidden under the horizon in the rays of the sun. The whole sky, though lit by the sidereal rays, seemed black by contrast with the whiteness of the waters. Conseil could not believe his eyes, and questioned me as to the cause of this strange phenomenon. Happily I was able to answer him. “It is called a milk sea,” I explained. “A large extent of white waves is often to be seen on the coasts of Amboyna, and in these parts of the sea.”  “But, sir,” said Conseil, “can you tell me what causes such an effect? For I suppose the water is not really turned into milk.”  “No, my boy; and the whiteness which surprises you is caused only by the presence of myriads of luminous little worm, gelatinous and without colour, of the thickness of a hair, and whose length is not more than seven-thousandths of an inch. These insects adhere to one another sometimes for several leagues.” “Several leagues!” exclaimed Conseil. “Yes, my boy; and you need not try to compute the number of these infusoria. You will not be able, for, if I am not mistaken, ships have floated on these milk seas for more than forty miles.” Towards midnight the sea suddenly resumed its usual colour; but behind us, even to the limits of the horizon, the sky reflected the whitened waves, and for a long time seemed impregnated with the vague glimmerings of an aurora borealisFind the TRUE Sentence:
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MCQ-> Read the following passage and answer the questions given below it. Certain words/phrases in the passage have been printed in bold to help you locate them while answering some of the questions.Marc Rodin flicked-off the switch of his transistor radio and rose from the table, leaving the breakfast tray almost untouched. He walked over to the window, lit another in the endless chain of cigarettes and gazed out at the snow-en-crusted landscape which the late arriving spring had not yet started to dismantle. He murmured a word quietly and with great venom, following up with other strong nouns and epithets that expressed his feeling towards the French President, his Government and the Action Service. Rodin was unlike his predecessor in almost every way. Tall and spare, with a cadaverous face hollowed by the hatred within, he usually masked his emotions with an un-Latin frigidity. For him there had been no Ecole Polytechnic to open doors to promotion. The son of a cobbler, he had escaped to England by fishing boat in the halcyon days of his late teens when the Germans overran France, and had enlisted as a private soldier under the banner of the Cross of Lorraine. Promotion through sergeant to warrant officer had come the hard way, in bloody battles across the face on North Africa under Koenig and later through the hedgerows of Normandy with Leclerc. A field commission during the fight for Paris had got him the officer’s chevrons his education and breeding could never have obtained and in post-war France the choice had been between reverting to civilian life or staying in the Army. But revert to what ? He had no trade but that of cobbler which his father had taught him, and he found the working class of his native country dominated by Communists, who had also taken over the Resistance and the Free French of the Interior. So he stayed in the Army, later to experience the bitterness of an officer from the ranks who saw a new young generation of educated boys graduating from the officer schools, earning in theoretical lessons carried out in classrooms the same chevrons he had sweated blood for. As he wanted them pass him in tank and privilege the bitterness started to set in. There was only one thing left to do, and that was join one of the colonial regiments, the tough crack soldiers who did the fighting while the conscript army paraded round drill squares. He managed a transfer to the colonial para-troops. Within a year he had been a company commander in Indo-China, living among other men who spoke and thought as he did. For a young man from a cobbler’s bench, promotion could still be obtained through combat, and more combat. By the end of the Indo-China campaign he was a major and after an unhappy and frustrating year in France he was sent to Algeria. The French withdrawal from Indo-China do the year he spent in France had turned his latent bitterness into a consuming loathing of politicians and Communists, whom he regarded as one and the same thing. Not until Franco was ruled by a soldier could she ever be weaned away from the grip of the treators and lickspittles who permeated her public life. Only in the Army were both breeds extinct. Like most combat officers who had seen their men die and occasionally buried the hideously mutilated bodies of those unlucky enough to be taken alive. Rodin worshipped soldiers as the true salt of the earth, the men who sacrificed themselves in blood so that the bourgeoisie could live at home in comfort. To learn from the civilians of native land after eight years of combat in the forests of Indo-China that most of them cared not a fig for the soldier, to read the denunciations of the military by the left-wing intellectuals for more trifles like the toturing of prisoners to obtain vital information, had set off inside Marc Rodin a reaction which combined with the native bitterness stemming from his own lack of opportunity, had turned into zealotry. He remained convinced that given enough backing by the civil authoritieS on the spot and the Government and people back home, the Army could have beaten the Viet-Minh. The cession of Indo-China had been a massive betrayal of the thousands of fine young men who had died there seemingly for nothing. For Rodin there would be, could be, no more betrayals. Algeria would prove it. He left the shore of Marseilles in the spring of 1956 as ner a happy man as he would ever be, convinced that the distant hills of Algeria would see the consummation of what he regarded as his life’s work, the apotheosis of the French Army in the eys of the world.What was the period when Rodin escaped to England ?
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MCQ-> Directions : Read the following passage carefully and answer the questions given below it. Certain words / phrases have been printed in BOLD to help you locate them while answering some of the questions. The great recession hasn't been great for free trade. An unemployment has risen throughout the world, governments have become more focused on protecting their own industries than on promoting international commerce. The U.S., though typically an enthusiastic supporter of open markets, in duded buy American clauses in its stimulus package and propped up its failing auto industry with handouts. But according to the Asian Development Bank (ADB), in the part of the world that was hit hardest by the trade crash-Asia, the number of Free Trade Agreements (FTAs) signed by Asian countries has grown from just three in 2000 to 56 by the end of August 2009. Nineteen of those FTAs are among 16 Asian economies, a trend that could help the region become a powerful trading bloc. The drive to lower trade barriers has taken on fresh urgency amid the recession. As Asian manufacturing networks become more intertwined and as Asian consumers become wealthier regional commerce is becoming critical to future economic expansions. Intraregional trade last year made up 57% of total Asian trade, up from 37% in 1980. In the past Asia produced for America and Europe, now Asia is producing for Asia. of course, Asia is still dependent on sales to the West. But FTAs could reduce the regions exposure to the United States by giving Asian companies preferential treatment in selling to Asian companies and consumers. There benefits could come with downsides, however. According to experts, FTAs create a nonlevel playing field with advantages for Asian countries. If the most dynamically growing part of the global economy gives the U.S. restricted access it will impact global balance. Companies in countries like the United States left out of the trade pacts could face disadvantages when trying to tap fast-growing Asian markets. This, in turn, could have a negative impact on efforts to rebalance excessive debt in the U.S. and excessive savings in Asia. Still, the benefits of greater regional integration could prove powerful enough to overcome the roadblocks. In Asia, the only thing everyone agrees upon is business. If it does, the world economy may never be the same.What do the Asian Development Bank statistics indicate?
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