题干

A team of engineers at Harvard University has been inspired by Nature to create the first robotic fly. The mechanical fly has become a platform for a series of new high-tech integrated systems. Designed to do what a fly does naturally, the tiny machine is the size of a fat housefly. Its mini wings allow it to stay in the air and perform controlled flight tasks.
“It’s extremely important for us to think about this as a whole system and not just the sum of a bunch of individual components (元件),” said Robert Wood, the Harvard engineering professor who has been working on the robotic fly project for over a decade. A few years ago, his team got the go-ahead to start piecing together the components. “The added difficulty with a project like this is that actually none of those components are off the shelf and so we have to develop them all on our own,” he said.
They engineered a series of systems to start and drive the robotic fly. “The seemingly simple system which just moves the wings has a number of interdependencies on the individual components, each of which individually has to perform well, but then has to be matched well to everything it’s connected to,” said Wood. The flight device was built into a set of power, computation, sensing and control systems. Wood says the success of the project proves that the flying robot with these tiny components can be built and manufactured.
While this first robotic flyer is linked to a small, off-board power source, the goal is eventually to equip it with a built-in power source, so that it might someday perform data-gathering work at rescue sites, in farmers’ fields or on the battlefield. “Basically it should be able to take off, land and fly around,” he said.
Wood says the design offers a new way to study flight mechanics and control at insect-scale. Yet, the power, sensing and computation technologies on board could have much broader applications. “You can start thinking about using them to answer open scientific questions, you know, to study biology in ways that would be difficult with the animals, but using these robots instead,” he said. “So there are a lot of technologies and open interesting scientific questions that are really what drives us on a day to day basis.”
【小题1】The difficulty the team of engineers met with while making the robotic fly was that __________.
A.they had no model in their mind
B.they did not have sufficient time
C.they had no ready-made components
D.they could not assemble the components
【小题2】It can be inferred from paragraphs 3 and 4 that the robotic fly __________.
A.consists of a flight device and a control system
B.can just fly in limited areas at the present time
C.can collect information from many sources
D.has been put into wide application
【小题3】Which of the following can be learned from the passage?
A.The robotic flyer is designed to learn about insects.
B.Animals are not allowed in biological experiments.
C.There used to be few ways to study how insects fly.
D.Wood’s design can replace animals in some experiments.
【小题4】Which of the following might be the best title of the passage?
A.Father of Robotic Fly
B.Inspiration from Engineering Science
C.Robotic Fly Imitates Real Life Insect
D.Harvard Breaks Through in Insect Study
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同类题1

   In the United States alone,over 100 million cell-phones are thrown away each year.Cell-phones are part of a growing mountain of electronic waste like computers and personal digital assistants.The electronic waste stream is increasing three times taster than traditional garbage as a whole.

Electronic devices contain valuable metals such as gold and silver.A Swiss study reported that while the weight of electronic goods represented by precious metals was relatively small in comparison to total waste,the concentration(含量)of gold and other precious metals was higher in So-called e-waste than in naturally occurring minerals.

Electronic wastes also contain many poisonous metals.Even when the machines are recycled and the harmful metals removed,the recycling process often is carried out in poor countries,in practically uncontrolled ways which allow many poisonous substances to escape into the environment.

Creating products out of raw materials creates much more waste material,up to 100 times more,than the material contained in the finished products.Consider again the cell-phone,and imagine the mines that produced those metals,the factories needed to make the box and packaging(包装)it came in.Many wastes produced in the producing process are harmful as well.

The U.S Environmental Protection Agency notes that most waste is dangerous in that"the production, distribution,and use of products-as well as management of the resulting waste-all result in greenhouse gas release." Individuals can reduce their contribution by creating less waste at the start-for instance,buying reusable products and recycling.

In many countries the concept of extended producer responsibility is being considered or has been put in place as an incentive(动机)for reducing waste.If producers are required to take back packaging they use to sell their products,would they reduce the packaging in the first place?

Governments' incentive to require producers to take responsibility for the packaging they produce is usually based on money.Why,they ask,should cities or towns be responsible for paying to deal with the bubble wrap(气泡垫)that encased your television?

From the governments' point of view,a primary goal of laws requiring extended producer responsibility is to transfer both the costs and the physical responsibility of waste management from the government and tax-payers back to the producers.

【小题1】By mentioning the Swiss study,the author intends to tell us that .
A.the weight of e-goods is rather small
B.natural minerals contain more precious metals
C.E-waste deserves to be made good use of
D.the percentage of precious metals is heavy in e-waste
【小题2】The responsibility of c-waste treatment should be extended .
A.from producers to governments
B.from governments to producers
C.from individuals to distributors
D.from distributors to governments
【小题3】What docs the passage mainly talk about?
A.The increase in e-waste.B.The creation of e-waste.
C.The seriousness of e-waste.D.The management of e-waste.

同类题2

Controlling Anger

Becoming angry is something beyond the control of people.【小题1】 Becoming angry can do a lot of damage,both mental and physical. However,there are methods for discovering how to control anger and not to suffer later.

·【小题2】 The moment you feel there are chances for you to become angry,get away from those circumstances(环境).In fact,there can be no better judge than you,for discovering what it is or who it is that makes you become angry,and then at that moment choosing to think about something else that can lighten your feelings.

·Keep a check on your breathing.【小题3】 By controlling the process of breathing,you can actually slow down your anger greatly. You can count till three as you breathe in,hold it for 3 seconds and again count till three while breathing out. You have to concentrate on the count as you do this and repeat this for as many times as required.

·【小题4】 For example, if you’re experiencing road rage while driving,you can choose to tell yourself that the person who overtook you by a vehicle was in a hurry as a result of some emergency and appreciate the fact that nothing major happened to your car. Repeat this form of self-talk to yourself every time you are in the middle of such an angry situation.

·Look for the support of other people.【小题5】 It needs to be clear right at the beginning as to why you are discussing your concerns with that individual. Let the other individual know what you want from him or her. After you’re done with your part of discussing about the circumstances,chances are that you’ll feel much better than before.

A.Talk to yourself positively.
B.Come to a stop as soon as you are angry.
C.Try to see the situation from a different view.
D.You can also ask for help from the one you rely on.
E.What you can do when you become angry is to breathe deeply.
F.In fact, almost all people at one point of time become angry.
G.You can imagine going to a place you consider to be calm as well as relaxing.

同类题3

Internet use appears to cause a decline in psychological well-being(安康), according to research at Carnegie Mellon University.
Even people who spent just a few hours a week on the Internet experienced more depression and loneliness than those who logged on less frequently, the two-year study showed. And it wasn’t that people who were already feeling bad spent more time on the Internet, but that using the Net actually appeared to cause the bad feeling.
Researchers are puzzling over the results, which were completely contrary to their expectations. They expected that the net would prove socially healthier than television, since the Net allows users to choose their information and to communicate with others.
The fact that Internet use reduces time available for family and friends may account for the drop in well-being, researchers suggested. Faceless, bodiless “virtual”(虚拟的)communication may be less psychologically satisfying than actual conversation, and the relationship formed through it may be shallower. Another possibility is that exposure to the wider world via the Net makes users less satisfied with their lives.
“But it’s important to remember this is not about the technology  per se; it’s about how it is used,” says psychologist Christine Riley of Intel, one of the study’s sponsors. “It really points to the need for considering social effects in terms of how you design applications and services for technology.”
【小题1】The best title for this passage would be ________.
A.Internet may Cause Depression
B.The Dark Side of Internet
C.How to Use Technology Properly
D.The Importance of Psychological Well-being
【小题2】Internet use may cause a decline in psychological well-being because ________.
A.people who were already feeling bad spend more time on the Internet
B.Internet users thought the world was wider than it really was
C.people were too eager to turn the “virtual” communication into reality
D.people have less time for actual communication with their family and friends
【小题3】What does the underlined Latin word “per se” (in Para. 5) mean?
A.probablyB.absolutely
C.oneselfD.itself
【小题4】What’s the tone of the passage?
A.Optimistic.B.Critical.
C.Objective.D.Pessimistic.

同类题5

   A newly-published study has shown that loneliness can spread from one person to another,like a disease. Researchers used information from the Framingham Heart Study,which began in 1948. The Framingham Heart Study gathers information about physical and mental health,personal behavior and diet. At first,the study involved(使参加)about 5,000 people in the American state of Massachusetts. Now more than 12,000 individuals(个人)are taking part.

Information from the Framingham Heart Study showed earlier that happiness can spread from person to person. So can behavior like littering and the ability to stop smoking.

Psychologist John Cacioppo,at the University of Chicago,led the recent study. He and other researchers tried to show how often people felt lonely. They found that the feeling of loneliness spread through social groups.

Having a social connection with a lonely person increased the chances that another individual would feel lonely. In fact,a friend of a lonely person was 52% more likely to develop feelings of loneliness. A friend of that person was 25%more likely. The researchers said this shows that a person could indirectly be affected by someone’s loneliness.

The effect was the strongest among friends. Neighbors were the second most affected group. The effect was weaker on husbands and wives,and brothers and sisters. The researchers also found that loneliness spread more easily among women than men.

The New York Times newspaper reported that,on average,people experience feelings of loneliness about 48 days a year. It also found that every additional(额外的)friend can decrease loneliness by about five percent,or two and a half fewer lonely days.

Loneliness has been linked to health problems like depression(抑郁症)and sleeping difficulties. The researchers believe that knowing the causes of loneliness could help reduce it.

The study suggested that people can take steps to stop the spread of loneliness. They can do this by helping individuals they know who may be experiencing loneliness. The result can be helpful to the whole social group.

【小题1】As for the Framingham Heart Study we can learn that __________.
A.it was only conducted in 1948B.it involves more than 12, 000 people
C.it was founded by John CacioppoD.it showed that any behavior could spread
【小题2】From the passage, we can learn that __________.
A.the behavior of littering doesn’t spread
B.a lonely person won’t have friends
C.everyone may be affected by others’ loneliness
D.lonely people don’t know the causes of their loneliness
【小题3】Which statement about the spread of loneliness is TRUE?
A.The spreading effect is the second strongest among friends.
B.No spreading effect is found on husbands and wives.
C.Women are more likely to be affected than men.
D.Brothers are more easily to be affected than neighbors.
【小题4】What is the main idea of the passage?
A.Action should be taken to help lonely people.B.People feel lonely for many reasons.
C.Ways to fight against loneliness.D.Lonely people can affect others.