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既能消食和胃，又能发散风寒的药物是
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治疗疝气，睾丸肿痛及乳房结块，最适宜的药物是
Directions: Read the following passages and then answer IN COMPLETE SENTENCES the questions which follow each passage. Scientists are preparing to boot up the world’s most powerful supercomputer, a machine with the power of 500,000 PCs and a thirst for electricity that will leave its owners with an annual bill of ￡25m. The computer, called Titan, will use graphics processors similar to those in PlayStation gaming consoles to tackle some of the toughest tasks in science. Until now most supercomputers have used normal processors souped-up versions of those in laptops and PCs. Decoding new flu strains—one of the most demanding jobs in computing—is one task that engineers at Oak Ridge National Laboratory in Tennessee might set Titan. The supercomputer could also design vaccines to stop the flu bugs before they can spread. Sumit Gupta, a senior engineer at Nvidia, the company that is making the Titan processors, said: "Computer simulations can explore lm different drug [vaccine] candidates within weeks or months." Titan will carry out 20,000 trillion calculations a second, about 4,000 trillion calculations a second faster than Sequoia, the world’s current fastest computer, which is used to simulate nuclear explosions. A typical PC carries out 40 billion calculations a second. "Oak Ridge is in the race to have the fastest supercomputer in the world," the laboratory said in a statement. Supercomputing has been one of the fastest and most revolutionary of technological trends. As with ordinary computers, its history goes back to the 1930s and 1940s when the first digital computers were built, with the first transistor-based machine being produced in 1956. The development of supercomputers owes much to the work of Seymour Cray, an electrical engineer who realized the potential of linking processors together to create much faster machines. Experts differ on which of his machines should be called the first supercomputer but Cray-1, built in 1976, is commonly cited. Back then its ability to perform 160m calculations a second was seen as revolutionary. Nowadays that machine would have a fraction of the computing power of a smartphone. "Computers like these have revolutionized science," said Paul Calleja, director of the high-performance computing centre at Cambridge University. "In the past, researchers devised theories and then they carried out experiments. What supercomputers do is offer us a third way—computer modelling. We can devise a theory about, say, the way atoms and molecules or materials might behave, and then build a computer model to see if it works." Such approaches are now standard throughout science and engineering. In the aviation industry, for example, where engineers once tested the effects of bird strikes on aircraft by throwing or firing a dead chicken into a jet turbine, they now have vast databases on the composition of chickens and their behaviour when they hit spinning turbines. Similarly, car designers use computer models to test how vehicles will crumple in a crash and what injuries the occupants might sustain. In the past, such tests could be conducted only by using real cars occupied by dummies or even dead bodies. Computer modelling has sharply cut the need for such testing. Titan will be made available to scientists in various fields. One programme will tackle climate change and how rising greenhouse gas emissions might affect different parts of the world. Another will study the way fuel burns in diesel engines spinning thousands of times a minute, to find ways of boosting efficiency. "These types of calculations require massive computing power," said Calleja, whose own supercomputer at Cambridge has been used to design America’s Cup sailing boats. "The pressure to build even more powerful machines is huge." Supercomputers are no longer the preserve of the military or academic establishments, however. Many high-street companies, from supermarkets to banks and insurance firms, own them. Tesco, for example, is investing in a ￡65m supercomputing system in Watford, Hertfordshire, to underpin its online retail and banking businesses. Such computing power, combined with data extracted from loyalty cards and other sources, means supermarkets can build models of consumer behaviour to predict what they will want to buy even before their customers know it. Walmart, the American owner of Asda, has been using a supercomputer for several years and has even combined it with weather forecasts to work out what products will be needed in stores when storms or other events arise. Researchers at Cambridge are now working on perhaps the most ambitious computing project of all—to build a machine 150 times faster than Titan to help search for planets capable of supporting life. The computer, capable of between 2m trillion and 3m trillion calculations a second, will be hooked up to the Square Kilometre Array, a giant radio telescope made up of thousands of radio dishes that is under construction across South Africa and Australia. Calleja said the supercomputer’s key task would be to collate and analyse all the data captured by each dish. "It is the most ambitious project we have ever attempted," he said. How are supercomputers connected with people’s daily life
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