Purdue University researchers have engineered flying robots that behave like hummingbirds, trained by machine learning algorithms (计算程序) based on various techniques the bird uses naturally every day. The robot would be able to fly better through collapsed buildings to find trapped victims.
Even though such a robot can’t see yet, it senses by touching surfaces. Each touch changes an electric current, which the researchers realized that they could track. Xinyan Deng, a professor, and her colleagues at Purdue have been trying to decode (破译) hummingbird flight so that robots can fly where larger aircraft can’t. Deng’s group studied hummingbirds themselves for many summers in Montana. They documented key hummingbird actions, such as making a rapid 180-degree turn, and translated them to computer algorithms that the robot could learn from when connected with a simulation (模拟操作).
Further study on the physics of insects and hummingbirds allowed Purdue researchers to build robots smaller than hummingbirds--and even as small as insects-without compromising the way they fly. The smaller the size, the greater the wing flapping frequency, and the more efficiently they fly. The robots have 3D-printed bodies and wings made of carbon fiber. The researchers have built one hummingbird robot weighing 12 grams--the weight of the average adult hummingbird. The hummingbird robot can lift up to 27 grams.
Designing their robots with higher lift gives the researchers more room to eventually add a battery and sensing technology, such as a-camera or GPS. Currently, the robot needs to be tied to an energy source while it flies-but that won’t be for much longer, the researchers say. The robots could fly silently just as a real hummingbird does, making them more ideal for covert (转换) operations.
Robotic hummingbirds would not only help with search-and-rescue tasks, but also allow biologists to more reliably study hummingbirds. In their natural environment through the senses of a realistic robot. This work is part of Purdue’s 1501° anniversary. This is one of the four themes of the celebration’s Ideas Festival, designed to show Purdue as an intellectual center solving real-world issues.
1.The hummingbird robot could be helpful in searching for victims .
A.in a very wide area B.in a desert
C.in a dark place D.in the sea
2.What can we know about the hummingbird robot?
A.It is as light as an insect. B.It can fly to any place.
C.It can see where to go. D.The smaller it is, the better.
3.What is the disadvantage of the robotic hummingbird at present?
A.It barely lifts its weight. B.It’s not equipped with a battery.
C.It can’t fly too high in the sky. D.It produces a little noise outside.
4.Besides being useful in rescues, the hummingbird robot can help .
A.biologists to study hummingbirds B.biologists to study wildlife
C.transport dangerous goods D.protect birds in the wild
Like many other students beginning graduate school, I was quickly charged with responsibilities and had to find time for studying by letting goof many other things I valued. Letting go of football and the violin was, however, self-defeating: it might have brought me more time in the short term, but spending that extra time on work only’ made me more stressed and less productive.
Towards the end of the MSC (Master of Science program) started to lose my motivation and curiosity for science and research, as well as my creativity. Spending so much time and energy in the laboratory, and focusing all my attention on my thesis and courses, made me feel down and almost totally uninterested in my field - not to mention short-tempered and oversensitive in my personal communications.
Over time, I learnt from these experiences. When I started my PhD, I focused on balancing academic success with personal time-off, and made personal happiness a priority (首要事情) in my weekly schedule. My mentor (导师) and I discussed my work-life balance early in my program, and we arrange our lab responsibilities accordingly.
I set boundaries for myself in new ways: ‘rather than doing lab work all weekend, I’d play football or the violin, or visit loved ones, before allowing myself to work fora few hours.
This was hard at first: I worried that it would affect my standing with my peers, and superiors, but I had learnt from experiences that an overloaded schedule can drain (使疲劳) you so much that you become unfocused and start making mistakes or forgetting important details.
Since establishing a better work-life balance, I’ve been doing well in graduate school. Outside the lab, I’ve been able to take up a few leadership positions at my university because I’m not as stressed with my work. I serve as our department’s student councilor and I am also vice-president academic in the Health Sciences Graduate Students’ Association. My advice is this: a healthy work-life balance isn’t a luxury; it’s a key part of success in graduate programs.
1.What is the author’s problem?
A.He must study hard to graduate.
B.He must give up his hobby for study,
C.He didn’t know how to study more effectively.
D.He didn’t know how to deal with pressure.
2.Paragraph 2 shows ________.
A.the challenges of an MSC program
B.the consequences of giving up hobbies
C.the benefits of focusing on schoolwork
D.the importance of balancing study and hobbies
3.To balance academic and personal life, the author ________.
A.asks his peers for help
B.seeks to reduce his lab duties
C.puts his hobbies first more often
D.avoids schoolwork at weekends at all
4.When the author gets his hands too full, he ________.
A.tends to put things on hold
B.tends to lose the attention to details
C.will lose his patience with his academic work
D.will make a new schedule accordingly
5.What can be inferred from the author’s personal experience?
A.It’s never too late to make a change in the university.
B.It’s easy to be work-life balanced in our lives.
C.Multi-tasking has many advantages in the university.
D.Work-life balance is necessary in the university.
It is often said that “a picture is worth a thousand words.” That is certainly true of the images of fleeting moments of nature submitted by international ecologists and students for the British Ecological Society’s (BES) annual photography competition. Here are a few of 2019’s winning entries.
Red Night
Photographed by Roberto Garcia Roa, it was declared last year’s overall winner. The image captures both the beauty of the magnificent snake and its fear of human threats like fires. The ecologist says, “During my visit to Madagascar, I had the pleasure of finding this snake and photographing it. To offer a dramatic scene reflecting the conditions that these snakes are suffering, I used an external red light as a source of light to capture the environment.”
The Rhino’s Annual Haircut
It was photographed by ecologist Molly Penny. The ongoing demand for rhino (犀牛) horns has reduced the population to just 30,000 globally. To try to save the species, ecologists in South Africa, home to over 20,000 southern white rhinos, have decided to saw off (锯掉) it part of the animals’ horns, which regrow every year. “The Rhino’s Annual Haircut,” captured beautifully in the black-and-white photo by Molly Penny from the University of the West of England, reduces the risk of the animals being cruelly murdered.
For the Love of Flamingos
Photographed by Peter Hudson, it captures a heart-shaped cloud of pink flamingos in Kenya, which is truly a sight like none other. The ecologist says, “Flamingos are all legs and necks but meanwhile beautiful and fascinating and I admit I have a deep passion for them, so I was thrilled when, flying high over Lake Magadi, I watched this flock from themselves into a heart shape.”.
Flames in Flumes
Photographed by Nilanjan Chatterjee, it captures a water redstart waiting to catch an insect near a small waterfall. It was the best overall student submission. The photographer wanted to show the struggle the river birds are likely to face from the slowdown in water flow due to planned dams in rivers across India.
1.What can we know about “Red Night”?
A.Roberto Garcia Roa suffered a lot to take it.
B.It describes a snake’s suffering in the fires.
C.It won the first place in 2019 BES’ photography competition.
D.Roberto Garcia Roa was very frightened when he took it.
2.What may be the topic of “The Rhino’s Annual Haircut”?
A.The tips on saving an endangered rhino.
B.The cruelty of killing an endangered rhino.
C.The scene of taking part of a horn from a rhino.
D.The method of helping a rhino to grow a horn again.
3.Where was “For the Love of Flamingos” photographed?
A.In South Africa. B.In Kenya.
C.In India. D.In Madagascar.
4.How is “Flames in Flumes” different from the other pictures?
A.It is a student’s work.
B.It was photographed on an island.
C.It is a black-and-white photo.
D.It shows wild animals’ suffering.
5.What is the purpose of the text?
A.To introduce a photography competition.
B.To remind us to protect some animals.
C.To warn us of worsening nature.
D.To introduce some winning photos.
“Excuse me,” he waved to the waiter. The waiter arrived at our table. “I ________ cottage cheese, but this is the mushroom.” The waiter returned with a(n) ________ smile on his face and said, “I’m sorry sir. I ________ took the order for the mushroom.” “Then change it immediately,” I said angrily. I had ________ my professor, who had retired as CEO of a billion-dollar multinational corporation, to lunch at the ________ restaurant. The waiter smiled awkwardly. I ________ to begin the “do-you-know-who-he-is” dialogue. But my professor was quicker. He said, “It’s alright. Just don’t ________ me for both dishes,” and laughed. “No, sir. Sorry, sir. Thank you, sir,” the waiter said and the ________ and gratefulness were written all over his face.
“Why did you do that, sir?” I asked, ________ .”It’s his duty to change your dish,” I said. “See how crowded the restaurant is? It’s a(n) ________ noon. Vernon,” my professor said. “Changing my order would mean more ________ for him and the chef. Maybe the waiter is ________. He probably would get a warning from the manager for this ________. Why put them through all this ________? This mushroom isn’t bad.”
When the bill arrived, my professor ________ paying it. He even left a big tip. When we walked out, he smiled at the waiter, who ________ so low that I thought he’d break his back. My professor also smiled and ________ the doorman when he thanked us for visiting.
Here was my professor, Mr. Smith, being sympathetic to people below his ________, and treating them like friends. “The true measure of a man is ________ he treats someone who can do him absolutely no good,” said Samuel Johnson. I’ll follow my professor’s ________ and try my best to do the same.
1.A.mentioned B.ignored C.noticed D.ordered
2.A.apologetic B.ridiculous C.meaningful D.unnecessary
3.A.accurately B.accidently C.primarily D.appropriately
4.A.referred B.introduced C.brought D.guided
5.A.remote B.common C.elegant D.self-service
6.A.happened B.prepared C.managed D.failed
7.A.charge B.blame C.thank D.punish
8.A.peace B.confidence C.worry D.relief
9.A.excited B.moved C.surprised D.disappointed
10.A.normal B.busy C.hot D.unique
11.A.work B.income C.value D.practice
12.A.smart B.careful C.friendly D.new
13.A.actively B.duty C.mistake D.intention
14.A.break B.boredom C.training D.trouble
15.A.put on B.insist on C.come on D.get on
16.A.bowed B.stood C.sat D.fell
17.A.acknowledge B.recognized C.observed D.understood.
18.A.age B.status C.expectation D.standard
19.A.when B.why C.how D.what
20.A.call B.advice C.procedure D.example
—I’ve been promoted to the director of HR and I’m wondering whether I can ask for a big pay rise .
—________. After all, the economy is struggling these days.
A.You can make it. B.Good for you C.You’ve gone too far D.It’s up to you
Covid-19, the most deadly virus in recent years, began to attack people at the beginning of this year, from ________ effect people are still suffering.
A.that B.those C.whose D.what
