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阅读下面的短文，文中有15处空白，每处空白给出了4个选项，请根据短文的内容从4个选项中选择1个最佳答案。 A Wonderful Chip It is tiny, only about a quarter of an inch square, and quite flat. Under a microscope, it resembles a stylized Navaho rug or the aerial view of a railroad (51) yard. Like the (52) of sand on a beach, it is made mostly of silicon, (53) oxygen, the most abundant element on the surface of the earth. Yet this inert fleck (小片), still unfamiliar to the (54) majority of Americans, has astonishing power. It is cheap to (55) produce, fast, infinitely versatile and convenient. The miracle chip represents a quantum(重大的) (56) in the technology of mankind, a development that (57) the past few years has acquired the force and significance associated with the development of hand tools or the discovery of the steam engine. Just as the Industrial Revolution (58) an immense (59) of tasks from men’s (60) and enormously expanded productivity, (61) the microcomputer is rapidly assuming huge burdens of drudgery from the human brain and (62) expanding the mind’s capacities (63) that man has only begun to grasp. (64) the chip amazing feats of (65) become possible in everything from automobile engines to university laboratories and hospitals, from farms to banks and corporate offices, from outerspace to a baby’s nursery.
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阅读下面这篇短文，短文后有2项测试任务：(1)第23～26题要求从所给的6个选项中为第2—5段每段选择1个正确的小标题；(2)第27～30题要求从所给的6个选项中选择4个正确选项，分别完成每个句子。 Alaska1. In 1868 Americans welcomed Alaska into the Union as the 49th state, symbolizing a change of attitude from that held in 1867, when the peninsula was purchased from Russia. Then, most Americans had little interest in 1,500,000 square kilometers “of icebergs and polar bears”— beyond Canada’s western borders, far from the settled areas of the United States.2. In those sections of the state which lie above the Arctic Circle, Alaska still is a land of icebergs and polar bears. Ice masses lie buried in the earth, which is permanently frozen to a depth of 90 or more meters. From early May until early August, the midnight sun never sets on this flat, treeless region, but the sun cannot melt the icy soil more than two-thirds of a meter down.3. Alaska is America’s largest state, but only about 325,000 people live there. According to estimates, 800,000 hectares of its land area are fit for plowing but only about 640,000 hectares are being cultivated.4. Arctic Alaska has been the home of Eskimos for countless centuries. It is believed that the Eskimos moved there from Mongolia or Siberia, probably crossing Bering Strait, named for Vitus Bering, the Danish sea captain who discovered Alaska on his voyage for Russia in 1741. The Eskimos are the state’s earliest known inhabitants. Russian fur traders established settlements but, by the time Alaska was sold to the United States, most of the traders had departed.5. In 1896 gold was discovered near the Klondike River in Canada just across the Alaskan border. Thousands of Americans rushed to the region on their way to Klondike; some never returned. Alaska was never completely cut off again, although even today transportation is a major problem. There are only two motor routes from the U. S. mainland, and within the state, every town has its own airfield. Planes fly passengers, mail and freight to the most distant villages.6. The gold that changed life so suddenly for Alaska was soon ended, and although many stories about mining camps have become part of American literature, the gold from Alaskan earth contributed less to economic progress than the fish from Alaskan waters. The fish caught in a single year range in value from $ 80 million to $ 90 million. Fur-bearing animals are plentiful in the forests and streams, and valuable fur seals inhabit the waters. After fishing, the state’s chief industry is lumber and the production of wood pulp. In recent years, Alaska’s single most important resource has become oil. The state also has large deposits of coal, copper,gold and other minerals. According to statistics, ______of the total area of Alaska has been used for farming.
第三篇 Problems of Internet The proportion of works cut for the cinema in Britain dropped from 40 per cent when I joined the BBFC in 1975 to less than 4 per cent when I left. But I don’t think that 20 years from now it will be possible to regulate any medium as closely as I regulated film. The Internet is, of course, the greatest problem for this century. The world will have to find a means, through some sort of international treaty of United Nations initiative, to control the material that’s now going totally unregulated into people’s homes. That said, it will only take one little country like Paraguay to refuse to sign a treaty for transmission to be unstoppable. Parental control is never going to be sufficient. I’m still very worried about the impact of violent video games, even though researchers say their impact is moderated by the fact that players don’t so much experience the game as enjoy the technical manoeuvres (策略)that enable you to win. But in respect of violence in mainstream films, I’m more optimistic. Quite suddenly, tastes have changed, and it’s no longer Stallone or Schwarzenegger who are the top stars, but Leonardo DiCaprio—that has taken everybody by surprise. Go through the most successful films in Europe and America now and you will find virtually none that we are violent. Quentin Tarantino didn’t usher in a new, violent generation, and films are becoming much more prosocial than one would have expected. Cinemagoing will undoubtedly survive. The new multiplexes are a glorious experience, offering perfect Sound and picture and very comfortable seats, thins which had died out in the 1980s. I can’t believe we’ve achieved that only to throw it away in favor of huddling around a 14-inch computer monitor to watch digitally delivered movies at home. It will become increasingly cheap to make films, with cameras becoming smaller and lighter but remaining very precise. That means greater chances for new talent to emerge, as it will be much easier for people to learn how to be better film-makers. People’s working lives will be shorter in the future, and once retired they will spend a lot of time learning to do things that amuse them—like making videos. Fifty years on we could well be media-saturated as producers as well as audience; instead of writing letters, one will send little home movies entitled My Week. What kind of film does the author dislike______
消息缓冲通信技术是一种高级通信机制，由Hansen首先提出。 (1)试述高级通信机制与低级通信机制P、V原语操作的主要区别。 (2)请给出消息缓冲机制(有界缓冲)的基本原理。 (3)消息缓冲通信机制(有界缓冲)中提供发送原语send(receiver，a)，调用参数a表示发送消息的内存区首地址，试设计相应的数据结构，并用P、V原语操作实现Send和Receive原语。
Astronaut Jim Voss has enjoyed many memorable moments in his career, including three spaceflights and one space walk. But he recalls with special fondness a decidedly earthbound (为地球引力所束缚的) experience in the summer of 1980 when he participated in the NASA-ASEE Summer Faculty Fellowship Program. Voss, then a science teacher at West Point, was assigned to the Marshall Space Flight Center’s propulsion lab in Alabama to analyze why a hydraulic fuel pump seal on the space shuttle was working so well when previous seals had failed. It was a seemingly tiny problem among the vast complexities of running the space program. Yet it was important to NASA because any crack in the seal could have led to destructive results for the astronauts who relied on them. "I worked a bit with NASA engineers," says Voss, "but I did it mostly by analysis. I used a handheld calculator, not a computer, to do a thermodynamic(热力学的) analysis." At the end of the summer, he, like the other NASA-ASEE fellows working at Marshall, summarized his findings in a formal presentation and detailed paper. It was a valuable moment for Voss because the ASEE program gave him added understanding of NASA, deepened his desire to fly in space, and intensified his application for astronaut status. It was not an easy process. Voss was actually passed over when he first applied for the astronaut program in 1978. Over the next nine years he reapplied repeatedly, and was finally accepted in 1987. Since then he has participated in three space missions. The 50-year-old Army officer, who lives in Houston, is now in training for a four-month mission as a crew member on the International Space Station starting in July 2000. Voss says the ASEE program is wonderful for all involved. "It brings in people from the academic world and gives NASA a special property for a particular period of time. It brings some fresh eyes and fresh ideas to NASA, and establishes a link with our colleges and universities," Voss explains. "There’s an exchange of information and an exchange of perspectives that is very important." For the academic side, Voss says, "the ASEE program also brings institutions of higher learning more insight into new technology. We give them an opportunity to work on real world problems and take it back to the classroom.\ How many flights will Voss have finished if his four-month mission starts in July 2000
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