题目内容

汇率并轨之后,外汇留成比例上升。( )

A. 对
B. 错

查看答案
更多问题

Both Boeing and Airbus have trumpeted the efficiency of their newest aircraft, the 787 and A350 respectively. Their clever designs and lightweight composites certainly make a difference. But a group of researchers at Stanford University, led by Ilan Kroo, has suggested that airlines could take a more naturalistic approach to cutting jet-fuel use, and it would not require them to buy new aircraft. The answer, says Dr. Kroo, lies with birds. Since 1914, and a seminal paper by a German researcher called Carl Wieselsberger, scientists have known that birds flying in formation—a V-shape, echelon or otherwise—expend less energy. The air flowing over a bird’s wings curls upwards behind the wingtips, a phenomenon known as upwash. Other birds flying in the upwash experience reduced drag, and spend less energy propelling themselves. Peter Lissaman, an aeronautics expert who was formerly at Caltech and the University of Southern California, has suggested that a formation of 25 birds might enjoy a range increase of 71%. When applied to aircraft, the principles are not substantially different. Dr. Kroo and his team modeled what would happen if three passenger jets departing from Los Angeles, San Francisco and Las Vegas were to rendezvous over Utah, assume an inverted V-formation, occasionally swap places so all could have a turn in the most favourable positions, and proceed to London. They found that the aircraft consumed as much as 15% less fuel (with a concomitant reduction in carbon-dioxide output). Nitrogen-oxide emissions during the cruising portions of the flight fell by around a quarter. There are, of course, kinks to be worked out. One consideration is safety, or at least the perception of it. Would passengers feel comfortable travelling in convoy’ Dr. Kroo points out that the aircraft could he separated by several nautical miles, and would not be in the unnervingly easy groupings favoured by display teams like the Red Arrows. A passenger peering out of the window might not even see the other planes. Whether the separation distances involved would satisfy air-traffic-control regulations is another matter, although a working group at the International Civil Aviation Organization has included the possibility of formation flying in a blueprint for new operational guidelines. It remains to be seen how weather conditions affect the air flows that make formation flight more efficient. In zones of increased turbulence, the planes’ wakes will decay more quickly and the effect will diminish. Dr. Kmo says this is one of the areas his team will investigate further. It might also he hard for airlines to coordinate the departure times and destinations of passenger aircraft in a way that would allow them to gain from formation flight. Cargo aircraft, in contrast, might be easier to reschedule, as might routine military flights. As it happens, American’s armed forces are on the ease already. Earlier this year the country’s Defense Advanced Research Projects Agency announced plans to pay Boeing to investigate formation flight, though the programme has yet to begin. There are reports that some military aircraft flew in formation when they were low on fuel during the Second World War, hut Dr. Lissaman says they are apocryphal. "My father was an RAF pilot and my cousin the skipper of a Lancaster lost over Berlin," he adds. So he should know. From the first two paragraphs, we can learn that ______.

A. energy cost reduced in a formation of V-shape and echelon or otherwise
B. 25 birds might enjoy 71% less energy consuming
C. a naturalistic airline works well than clever designs and lightweight composites
D. Kroo and his group are opposites who think that buying new aircraft is wasteful

上腹痛具有周期性和节律性,呕吐物呈咖啡残渣样,临床上最可能的诊断是( )

A. 急性胃黏膜病变
B. 慢性胃炎
C. 胃溃疡
D. 胃黏膜脱垂症
E. 胃癌

带有鸡鸣样吼声常见的疾病是( )

A. 极度虚弱病
B. 肺结核
C. 肺癌
D. 声带炎
E. 百日咳

Yasuhisa Shizoki, a 51-year old MP from Japan’s ruling Liberal Democratic Party (LDP), starts tapping his finger on the dismal economic chart on his coffee table. "Unless we change the decision-making process," he says bluntly, "we are not going to be able to solve this kind of problem." With the economy in such a mess, it may seem a bit of a diversion to be trying to sort out Japan’s political structures as well as its economic problems.Since co-writing a report on political reform, which was released by an LDP panel last week, Mr Shiozaki has further upset the party’s old guard. Its legionaries, flanked by columns of the bureaucracy, continue to hamper most attempts to overhaul the economy. Junichiro Koizumi was supposed to change all that, by going over their heads and appealing directly to the public. Yet nearly a year after becoming prime minister, Mr Koizumi has precious little to show for his efforts. His popularity is now flagging and his determination is increasingly in doubt.As hopes of immediate economic reform fade, optimists are focusing on another potential benefit of Mr Koizumi’s tenure. They hope that his highly personalized style of leadership will pave the way for a permanent change in Japanese politics: towards more united and authoritative cabinets that are held directly accountable for their policies. As that hap pens, the thinking goes, real economic reforms will be able to follow. Unfortunately, damage limitation in the face of scandal too often substitutes for real reform. More often, the scandals serve merely as distractions. What is really needed is an overhaul of the rules themselves.A leading candidate for change is the 40-year-old system--informal but religiously followed--through which the LDP machinery vets every bill before it ever gets to parliament. Most legislation starts in the LDP’s party committees, which mirror the parliamentary committee structure. Proposals then go through two higher LDP bodies, which hammer out political deals to smooth their passage. Only then does the prime minister’s cabinet get fully involved in approving the policy. Most issues have been decided by the LDP mandarins long before they reach this point, let alone the floor of parliament, leaving even the prime minister limited influence, and allowing precious little room for public debate and even less for accountability.As a result, progress will probably remain slow. Since they know that political reform leads to economic reform, and hence poses a threat to their interests, most of the LDP will resist any real changes. But at least a handful of insiders have now bought into one of Mr Koizumi’s best slogans: "Change the LDP, change Japan. The diversion Yasuhisa Shizoki enjoys is mentioned in the text to()

A. to introduce the topic of economic reforms
B. to honor his unique service to the LDP
C. to highlight his ability to solve problems
D. to show how he sort out his slogans

答案查题题库