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,” 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 fly 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.”
1.Which of the following statements was the difficulty engineers met while making the robotic fly?
A.They did not have sufficient fund.
B.No ready-made components were available.
C.There was no model in their mind.
D.It was hard for them to assemble the components.
2.What do we know about the robotic fly?
A.The robotic fly has been put into wide application.
B.The robotic fly consists of a flight device and a control system.
C.The robotic fly can collect information from many sources.
D.The robotic fly can fly well with the cooperation of individual components.
3.Which of the following can be learned from the passage?
A.The robotic fly can replace animals in some experiments.
B.Animals are not allowed in biological experiments.
C.The robotic fly is designed to learn about insects.
D.There used to be few ways to study how insects fly.
4.Which of the following might be the best title of the passage?
A.The Development of Robotic Fly
B.Robotic Fly Promotes Engineering Science
C.Harvard’s Efforts in Making Robotic Fly
D.Robotic Fly Imitates Real Life Insect
Boomerang children who return to live with their parents after university can be good for families, leading to closer, more supportive relationships and increased contact between the generations, a study has found.
The findings contradict research published earlier this year showing that returning adult children trigger a significant decline in their parents’ quality of life and wellbeing.
The young adults taking part in the study were “more positive than might have been expected” about moving back home – the shame is reduced as so many of their peers are in the same position, and they acknowledged the benefits of their parents’ financial and emotional support. Daughters were happier than sons, often slipping back easily into teenage patterns of behaviour, the study found.
Parents on the whole were more uncertain, expressing concern about the likely duration of the arrangement and how to manage it. But they acknowledged that things were different for graduates today, who leave university with huge debts and fewer job opportunities.
The families featured in the study were middle-class and tended to view the achievement of adult independence for their children as a “family project”. Parents accepted that their children required support as university students and then as graduates returning home, as they tried to find jobs paying enough to enable them to move out and get on the housing ladder.
“However,” the study says, “day-to-day tensions about the prospects of achieving different dimensions of independence, which in a few extreme cases came close to conflict, characterized the experience of a majority of parents and a little over half the graduates”.
Areas of divergence included chores, money and social life. While parents were keen to help, they also wanted different relationships from those they had with their own parents, and continuing to support their adult children allowed them to remain close.
1.What is the finding of the previous research?
A.Boomerang children made their parents happier.
B.The parents were looking forward to their children’s return.
C.The parents’ quality of life became worse than before.
D.Boomerang children never did any housework.
2.What are college graduates’ attitudes towards returning home?
A.They are ashamed of turning to their parents for help.
B.They are glad that they could come back.
C.They are doubtful about whether they should return.
D.They are proud to be independent from the family.
3.What is the reason for the “boomerang children” phenomenon?
A.The children want to keep in closer touch with their parents.
B.The parents want to provide support to their children.
C.It is harder for the children to secure a satisfying job.
D.There is more housework needed to be done by the children.
4.The underlined word “divergence” in paragraph 7 may be best replaced by ________.
A.disagreement B.harmony C.responsibility D.cooperation
Rebecca Munkombwe, an 11-year-old girl from Zimbabwe, is regarded as a hero for saving a 9-year-old friend from the jaws of a crocodile by jumping or、the crocodile and gouging (挖) its eyes out.
According to Zimbabwean media, Rebecca and her friends had just got back from a swim in a stream near their home village when they heard the screams corning from the water. She was shocked to see her 9-year-old friend Latoya Muwani being dragged into the water by a crocodile. While all the other children were running scared, Rebecca ran toward the water, jumped on top of the crocodile and started beating it with her bare fists. However, that didn’t seem to bother the crocodile at all, so she then used her fingers to gouge its eyes out until it loosened its grasp of Latoya. Once she was free, Rebecca swam with her to the bank.
Surprisingly, the 11-year-old heroine managed to save her young friend without suffering any wounds, while Latoya was lucky to escape with just mild wounds that were later treated at a regional hospital. Latoya’s parents praised Rebecca’s courage and thanked her for saving their daughter’s life. “I was at work when I learnt that my daughter had been attacked by a crocodile while swimming. For a moment I thought of the worst before I learnt that she’d survived after being saved by Rebecca,” Latoya’s father, Fortune Muwani, said. “I don’t know how she managed to do that, but I’m grateful to her.”
Local authorities confirmed the crocodile attack, adding that the number of such incidents was increasing. Apparently, the lack of easily accessible water sources (水源) is forcing women and children to use unprotected sources like this crocodile-infested (遍布鳄鱼的) stream.
1.What made Rebecca Munkombwe a hero?
A.Her catching a crocodile hare-handed.
B.Her rescuing a drowning friend in time.
C.Her helping a friend out of deadly danger.
D.Her making friends with a wild crocodile.
2.Which of the following words can best describe Rebecca?
A.Brave and smart. B.Calm and careful.
C.Honest and considerate. D.Courageous and patient.
3.What message do Fortune Muwani’s words convey?
A.He knew every detail about the rescuing process.
B.Latoya’s conditions were far better than expected.
C.Latoya’s being attacked by a crocodile sounded unbelievable.
D.He regretted not accompanying Latoya while she was swimming.
4.Why were crocodile attacks on the rise?
A.Because people have poor awareness of safety.
B.Because people enjoy getting close to animals in the wild.
C.Because people have little knowledge of accessible water sources.
D.Because people have to share limited water sources with wild animals.
Dive into Jason deCaires Taylor's underwater art exhibits from around the world
Creating the world's first underwater sculpture(雕像) park in Grenada in 2006, and with over 1,000 underwater artworks across the globe, deCaires Taylor has artfully highlighted the threats to our oceans while actively helping to create new life in them.Here are some of the underwater art exhibits.
Molinere Underwater Sculpture Park
Grenada, West Indies
Installed in 2006 after Molinere Bay suffered destructive damage from the 2004 Hurricane Ivan, these 75 underwater art pieces formed the world's first underwater sculpture park and was name done of National Geographic's 25 Wonders of the World.It now provides a new habitat for marine life,and it also draws divers and glass-bottomed boats away from more delicate reefs nearby.
Ocean Atlas
Nassau, Bahamas
Off the coast of Nassau sits the world's largest underwater sculpture, shallow enough for divers to view.This 60-ton,16-foot tall statue of a young Bahamian girl appears to hold up the ocean, just like her Greek namesake (同名人物) Atlas, who suspended the heavens in Greek myth(神话) .
The Rising Tide
London, U.K.
Unlike most of deCaires Taylor's works, these sculptures can be seen from land,on the banks of the River Thames, emerging during low tide. Within sight of the Houses of Parliament, they are a nod to the Four Horsemen of the Apocalypse and are a reminder of rising sea levels and the denial of climate change.
Museum of Underwater Art
Great Barrier Reef, Australia
Expected to open to the public in early 2020, deCaires Taylor's latest project aims to rehabilitate parts of the world's largest reef system. Works in the underwater museum include a partially-submerged(半淹没的)figure that changes color as the sea warms and which can be seen from shore, and even a submerged coral-covered greenhouse.
1.What do deCaires Taylor's underwater art exhibits have in common?
A.Becoming National Geographic's Wonders of the World.
B.Sharing names with gods in Greek myth.
C.Changing colors with water temperature.
D.Combining art with saving ocean creatures.
2.Where can you see the largest underwater sculpture?
A.Grenada. B.Nassau.
C.London. D.Great Barrier Reef.
3.Which is intended to save the world's largest reef system?
A.Molinere Underwater Sculpture Park.
B.Ocean Atlas.
C.The Rising Tide.
D.Museum of Underwater Art.
听下面一段独白，回答以下小题。
1.Why do some people say they never have dreams according to Dr. Garfield ?
A.They forget about their dreams.
B.They don’t want to tell the truth.
C.They have no bad experiences.
2.Why did Davis stop having dreams?
A.He got a serious heart attack.
B.He was too sad about his brother’s death
C.He was frightened by a terrible dream.
3.What is Dr. Garfield s opinion about dreaming?
A.It is very useful.
B.It makes things worse.
C.It prevents the mind from working.
4.Why do some people turn off their dreams completely?
A.To sleep better.
B.To recover from illnesses.
C.To stay away from their problems.
听下面一段较长对话，回答以下小题。
1.Where does Michelle Ray come from?
A.A middle-sized city. B.A small town. C.A big city.
2.Which place would Michelle Ray take her visitors to for shopping?
A.The Zen Garden. B.The Highlands. C.The Red River area.
3.What does Michelle Ray do for complete quiet?
A.Go camping. B.Study in a library. C.Read at home.
4.What are the speakers talking about in general?
A.Late-night shopping. B.Holiday plan. C.Louisville.
