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Passage 2New-age Transport Computerized design, advanced materials and new technologies are being used to produce machines of a type never seen before. It looks as if it came straight from the set of Star Wars. It has four-wheel drive and rises above rocky surfaces. It lowers and raises its nose when going up and down hills. And when it comes to a river, it turns amphibious: two hydrojets power it along by blasting water under its body. There is room for two passengers and a driver, who sit inside a glass bubble operating electronic, aircraft-type controls. A vehicle so daring on land and water needs windscreen wipers-but it doesn’t have any. Water molecules are disintegrated on the screen’s surface by ultrasonic sensors. This unusual vehicle is the Racoon. It is an invention not of Hollywood but of Renault, a rather conservative French state-owned carmaker, better known for its family hatchbacks. Renault built the Racoon to explore new freedoms for designers and engineers created by advances in materials and manufacturing processes. Renault is thinking about startlingly different cars; other producers have radical new ideas for trains, boats and aeroplanes. The first of the new freedoms is in design. Powerful computer-aided design (CAD) systems can replace with a click of a computer mouse hours of laborious work done on thousands of drawing boards. So new products, no matter how complicated, can be developed much faster. For the first time, Boeing will not have to build a giant replica of its new airliner, the 777, to make sure all the bits fit together. Its CAD system will take care of that. But Renault is taking CAD further. It claims the Racoon is the world’s first vehicle to be designed within the digitized world of virtual reality. Complex programmes were used to simulate the vehicle and the terrain that it was expected to cross. This allowed a team led by Patrick Le Quement, Renault’s industrial-design director, to “drive” it long before a prototype existed. Renault is not alone in thinking that virtual reality will transform automotive design. In Detroit, Ford is also investigating its potential. Jack Telnac, the firm’s head of design, would like designers in different parts of the world to work more closely together, linked by computers. They would do more than style cars. Virtual reality will allow engineers to peer inside the working parts of a vehicle. Designers will watch bearings move, oil flow, gears mesh and hydraulics pump. As these techniques catch on, even stranger vehicles are likely to come along. Transforming these creations from virtual reality to actual reality will also become easier, especially with advances in materials. Firms that once bashed everything out of steel now find that new alloys or composite materials (which can be made from mixtures of plastic, resin, ceramics and metals, reinforced with fibres such as glass or carbon) are changing the rules of manufacturing. At the same time, old materials keep getting better, as their producers try to secure their place in the factory of the future. This competition is increasing the pace of development of all materials. One company in this field is Scaled Composites. It was started in 1982 by Burt Rutan, an aviator who has devised many unusual aircraft. His company develops and tests prototypes that have ranged from business aircraft to air racers. It has also worked on composite sails for the America’s Cup yacht race and on General Motors’ Ultralite, a 100-miles-per-gallon experimental family car built from carbon fibre. Again, the Racoon reflects this race between the old and the new. It uses conventional steel and what Renault describes as a new “high-limit elastic steel” in its chassis. This steel is 30% lighter than the usual kind. The Racoon also has parts made from composites. Renault plans to replace the petrol engine with a small gas turbine, which could be made from heat-resisting ceramics, and use it to run a generator that would provide power for electric motors at each wheel. With composites it is possible to build many different parts into a single component. Fiat, Italy’s biggest car maker, has worked out that it could reduce the number of components needed in one of its car bodies from 150 to 16 by using a composite shell rather than one made of steel. Aircraft and cars may increasingly be assembled as if they were plastic kits. Advances in engine technology also make cars lighter. The Ultralite, which Scaled Composites helped to design for General Motors, uses a two-stroke engine in a “power pod” at the rear of the vehicle. The engine has been developed from an East German design and weighs 40% less than a conventional engine but produces as much power. It is expected to run cleanly enough to qualify as an ultra-low emissions vehicle under California’s tough new rules. Look at the following design features and list of companies. Match each design feature with the correct company, A-E. Write the correct letter A-E in boxes 1-6 on your answer sheet. NB You may use any letter more than once. 1. a power pod 2. electronic controls 3. a composite body 4. elastic steel 5. aircraft prototypes 6. ultrasonic sensors
It suddenly ______ me how we could improve the situation.
从年画的艺术形式特点上，可以感受到：饱满的构图、鲜明的形象似乎潜藏有盼望大团圆、祈愿丰收和吃饱饭等意思；挺拔的线条，反映出健康、有力的含义；鲜明的色彩，体现出火红喜庆的意思。中国人偏爱红色，它象征太阳、温暖、热闹、吉祥等意思，所以年画上，人们挂红灯笼、穿红袄、扎红头绳，不光鞭炮是红的，连鲤鱼也多画成红的。能准确概括上面文字内容的一句话是（ ）。
下面哪个选项不属于点渗漏处理（）
下列关于国家助学贷款催收的说法，错误的是（ ）。
某些因素导致宿主免疫功能受损或机械性损伤，使体内正常微生物离开固有寄生部位而到达不习惯的寄生部位所引起的感染，称为（）
《中华人民共和国环境保护法》对县级以上人民政府关于突发环境事件应急机制的规定有哪些？
《建设项目竣工环境保护验收技术规范-生态影响类》规定了生态影响类建设项目竣工环境保护验收调查（）。
下列哪项是丘脑的非特异性投射系统的主要作用?（ ）
期货公司对其客户的交易进行结算，按照盈亏数量的不同，可以分为逐日盯市和逐笔对冲两种结算方式。（ ）
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