Scientists estimate that more than 95 percent of Earth’s oceans have never been observed, which means we have seen less of our planet’s ocean than we have the far side of the moon or the surface of Mars. The high cost of powering an underwater camera for a long time, by tying it to a research boat or sending a ship to recharge its batteries, is a steep challenge preventing widespread undersea exploration.
MIT researchers have taken a major step to overcome this problem by developing a battery-free, wireless underwater camera that is about 100,000 times more than other undersea cameras. The device takes color photos, even in dark underwater environments, and transmits image data wirelessly through the water.
The autonomous camera is powered by sound. It transforms mechanical energy from sound waves traveling through water into electrical energy that powers its imaging and communications equipment. After capturing and encoding (编码) image data, the camera also uses sound waves to transmit data to a receiver that reconstructs the image.
Because it doesn’t need a power source, the camera could run for weeks on end before retrieval, enabling scientists to search remote parts of the ocean for new species. It could also be used to capture images of ocean pollution or monitor the health and growth of fish raised in aquaculture farms.
“One of the most exciting applications of this camera for me personally is in the context of climate monitoring. We are building climate models, but we are missing data from over 95 percent of the ocean. This technology could help us build more accurate climate models and better understand how climate change impacts the underwater world,” says Fadel Adib, associate professor in the Department of Electrical Engineering and Computer Science.
1. What does paragraph l mainly tell us?| A．The introduction of new batteries. |
| B．The emphasis on scientists’ leading work. |
| C．The advertisement for underwater cameras. |
| D．The difficulty of widespread undersea exploration. |
| A．It is charged by batteries. |
| B．It uses sound waves to transmit data. |
| C．It changes sound waves into water energy. |
| D．It changes mechanical energy into electrical energy. |
| A．Being fetched. | B．Being destroyed. |
| C．Being out of control. | D．Being reconstructed. |
| A．It affects climate change efficiently. |
| B．It will be widely used in some fields. |
| C．It will help know more about Mars’ climate. |
| D．It monitors the health and growth of new species. |
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【推荐1】Along with silk and paper,gunpowder is another invention by Chinese and the Silk Road helped it spread to the West. The dating of gunpowder is as early as 850 AD. The Chinese used gunpowder to make fireworks and for signal flares. Gunpowder was also thought to have been used in medicine and in alchemy(炼金术). This invention seems to have been discovered in China by accident —by alchemists when doing experiments.
The gunpowder used for military purpose was first recorded in 919 AD. By the 11th century,explosive bombs filled with gunpowder were introduced and used in China. The words “fire cannon” “rocket” and “fireball” appeared time and again in the official Song history as well as two other books written during the same period.
The first detailed description of using the “fire cannon” in warfare was in connection with a battle fought in 1126 when the Song army used it against the invading enemy. The so-called “ fire cannon” was a tube made of bamboo filled with gunpowder which, when fired, threw a flaming missile towards the enemy. According to a description of a battle scene in 1132, it took two persons to carry a “fire cannon”, and the cannons were fired from a moving platform. And this platform had to be moved close to the wall of the besieged(被围攻的) city.
Gunpowder reached Japan, the Islamic countries and then Europe in the 13th century, and the Arabs improved gunpowder for military use. The early account of gunpowder in Europe was recorded by English philosopher Roger Bacon in the 13th century. One century later the Arabs used it to attack the Spanish town Baza and the next year in 1326 Florence ordered the manufacturing of cannon and cannon balls. From Italy the making of gunpowder soon spread to other European countries, and by the 1350s it had become an effective weapon on the battlefield.
1. Gunpowder was discovered _________.| A．by alchemists when they had an accident |
| B．by alchemists after studying it for a long time |
| C．accidentally by alchemists |
| D．experimentally by alchemists |
| A．Convenient. | B．Heavy. |
| C．Useless. | D．Simple. |
| A．“fire cannons” at early times would be less helpful if they were far away from the object |
| B．alchemists devoted themselves to the study of gunpowder |
| C．the Silk Road spread to the West because of the invention of gunpowder |
| D．the first detailed description of using “fire cannons” in warfare was in 1132 |
| A．Powerful Fire Cannons | B．Four Inventions of Ancient China |
| C．The Discovery of the Alchemy | D．Gunpowder |
【推荐2】Any dog owner can tell you that there’s no love like the one a pup gives you. Dogs love humans — and it turns out, that connection can actually help us train dog robots, too.
In a study published Wednesday in the journal PLOS ONE, researchers surveyed 153 dog owners about the types of behaviors they like to see in their pups. Owners responded with a variety of different types of actions they preferred. The researchers identified seven types of behaviors people love to see in their dogs. These behaviors could be programmed into robotic dogs to help make them friendlier, which would be beneficial in a number of ways.
The robot-pups can help provide the same mental health benefits for people as an actual dog while avoiding issues like being bitten or having to take the dog on annoying walks every now and again. In fact, there’s already some research that suggests the robot pets might help enrich the lives of the elderly and dementia (痴呆) patients by giving them companions to socialize with — improving cognition (认知) and even physical health in some cases.
But there’s a big issue researchers need to overcome: It might not actually be ethical (道德的) to make robot-pups. After all, is it right to potentially mislead an elderly patient with dementia into thinking that they’re interacting with a dog instead of a robot? The study even quotes philosopher Robert Sparrow who wrote about the issue of robot companions two decades ago. “For an individual to benefit significantly from ownership of a robot pet, they must systematically cheat themselves about the real nature of their relation with the animal,” Sparrow wrote in 2002, “and the design and production of these robots is unethical in some way as it encourages this trick.”
But even so, the potential for benefit is still there — enriching people’s life. So one day in the near future we might see robot-pups at the dog park or walking on the sidewalk alongside their owners.
1. What did the researchers’ study focus on?| A．Training and getting on with dogs. | B．Dogs’ behaviors preferred by people. |
| C．Different behaviors among dogs. | D．People’s attitudes towards dogs. |
| A．To show the benefits of robot-pups to people. |
| B．To stress the significance of researching on robot-pups. |
| C．To indicate the popularity of robot-pups among patients. |
| D．To explain the impact robot-pups have on solving social issues. |
| A．Its functions are limited. | B．It may go against honesty. |
| C．It will cost too much money. | D．It may have quality problems. |
| A．Doubtful. | B．Encouraged. | C．Indifferent. | D．Confident. |
【推荐3】Most animals can quickly transition from walking to jumping to crawling to swimming if needed without making major adjustments. Most robots cannot. But researchers at Carnegie Mellon University have created soft robots that can seamlessly shift from walking to swimming or crawling to rolling.
“We were inspired by nature to develop a robot that can perform different tasks and adapt to its environment without adding actuators (执行器) or complexity,” said Carmel Majdi, a professor in the Mechanical Engineering Department in CMU’s College of Engineering. “Our bistable (双稳态) actuator is simple, stable and durable, and lays the foundation for future work on dynamic, reconfigurable soft robotics.”
Matching how animals transition from walking to swimming to crawling to jumping is a big challenge for bio-inspired and soft robotics. For example, one robot the team created has four curved actuators attached to the corners of a cellphone-sized body made of two bistable actuators.
On land, the curved actuators act as legs, allowing the robot to walk. In the water, the bistable actuators change the robot’s shape, putting the curved actuators in an ideal position to act as propellers so it can swim.
“You need to have legs to walk on land, and you need to have a propeller to swim in the water. Building a robot with separate systems designed for each environment adds complexity and weight,” said Majidi. “We use the same system for both environments to create an efficient robot.”
The team created two other robots: one that can crawl and jump, and one inspired by caterpillars and pill bugs that can crawl and roll. The actuators require only a hundred millisecond of electrical charge to change their shape, and they are durable.
In the future, the robots could be used in rescue situations or to interact with sea animals or coral. Using heat-activated springs in the actuators could open up applications in environmental monitoring, haptics (触觉) and reconfigurable electronics and communication.
1. Which of the following can best replace the underlined word “seamlessly” in paragraph 1?| A．Theoretically. | B．Formally. |
| C．Perfectly. | D．Vividly. |
| A．Curious. | B．Proud. | C．Anxious. | D．Careful. |
| A．Searching for lost items. |
| B．Competing with human labors. |
| C．Making heat-activated springs. |
| D．Connecting with marine animals. |
| A．Soft robot shifts from land to sea with ease. |
| B．Bistable actuator is simple, stable and durable. |
| C．A system creates an efficient robot for land and sea. |
| D．Transition from walking to swimming is a grand challenge. |
【推荐1】A survey of 2, 000 American adults finds that an average American spends nearly $3, 000 a year on unused groceries (杂货).
The survey shows that when people do cook, a quarter of them always make more food than they’re able to finish, usually with the intention of having leftovers (剩菜剩饭). On average, people have leftovers to put into their fridges three times a week; however, they don’t always get around to using them up. Actually, a third admit they’re likely to forget about leftovers once they’re out of sight. Forgetting about food is one of the top reasons people end up having food waste, along with leftovers not being popular among family members(23%). While 4 in 10 have a strong desire to eat their leftovers, a quarter admit they get tired of eating the same thing before they’re able to finish.
“With the rapid rise of food costs, wasting groceries each week hurts both nature and consumers’ wallets, “says director of sustainability at HelloFresh, Jeffrey Yorzyk. “Families cook with the best intention of using their leftovers, but our research shows that they’re generally not consuming all of those leftovers. Getting creative with the food in your fridge can help families feel like they’re eating something new and exciting!”
For some people, what excites them at the supermarket doesn’t do it anymore when they get home. The survey shows that 38%admit they’ve thrown food away simply because they don’t feel like eating it after purchasing it. Some waste starts even before shoppers get home, as a fifth say they don’t know how much food they’ll use when grocery shopping.
With these foods, 22%are not confident they know the best methods to store foods to keep freshness. Happily, seven in ten are trying to cut down on food waste. In fact, once you’ve bought food at the grocery store, there are a number of strategies to ensure you can save it completely and cook it smartly.
1. Which is the percentage of Americans preferring to have leftovers?| A．23%. | B．25%. | C．33%. | D．40%. |
| A．Eating them up at once. | B．Deal with them inventively. |
| C．Using them to protect nature. | D．Giving them up to save money. |
| A．Attract the shoppers. | B．Produce leftovers. |
| C．Lose the freshness. | D．Go to the fridges. |
| A．Benefits of saving foods. | B．The art of cooking in the USA. |
| C．The recent studies of leftovers. | D．Ways to reduce grocery waste. |
【推荐2】While some gossip can be annoying and unprofessional, other types of gossiping can be fun, normal, even healthy and productive. Experts say that talking about others behind their backs doesn’t have to be a guilty office pastime — it can be a useful tool to direct the workplace and learn important information. “I think, generally, gossip is a good thing,” says Elena Martinescu, a research associate who’s studied the psychology of gossiping. “According to evolutionary theory, humans have developed gossip in order to form cooperation on a group.”
By talking about other people, we can learn whom to cooperate with and whom to stay away from, something that helps a group work better together. “This fixed behavior translates to the modern workplace.” she says, “It is equally important to be aware of which colleagues one can trust and who one should be careful with.”
“Gossip confirms the value of our emotions and can help us figure out where other people stand on things,” she says, “and gossip can help us make sure if we’re perceiving the world in the same way as other colleagues and coworkers receive it.” It is really about information gathering. So, if someone at work says something like Ralph has been taking a lot of sick leave recently,” it could open the door for others to share their judgments and evaluations that maybe Ralph’s frequent sick leave could account for his poor job performance, for example. It can help you calculate how much sick leave is regarded as “appropriate” among your colleagues as well as who is empathetic or mean towards Ralph.
Sometimes, though, gossiping is just random talks about people or structures you dislike. Maybe it’s tyrannous boss, or the team that work slowly. Yet this gossip can still provide a network of observations and warnings that provide an informal instruction of support outside traditional workplace channels like HR.
1. What is Elena Martinescu’s attitude towards gossip?| A．Indifferent. | B．Negative. | C．Doubtful. | D．Supportive. |
| A．Whom Ralph works well with. | B．How Ralph’s health condition is. |
| C．Who is kind or unfriendly to Ralph. | D．Whether sick leave is regarded as appropriate. |
| A．Unkind. | B．Wealthy. | C．Helpful. | D．Generous. |
| A．The Impact of Judging Workers Behind Their Backs. |
| B．The Surprising Benefits of Gossiping in the Workplace. |
| C．How Gossiping Helps You Win Trust in the Workplace. |
| D．Why Gossip is Always a Productive Tool in the Workplace. |
【推荐3】The winter migration (迁徙) season has arrived. With the cold wave heading down south, migratory birds from faraway places such as Siberia have begun to arrive at Dongting Lake, central China for the winter.
Dongting Lake in central China’s Hunan Province is the country’s second-largest freshwater lake. When the temperature rises after a short cold time, locals call the 10th lunar month “Indian summer.” During this time, the lake’s water level drops and sedges (莎草) grow, allowing wintering birds to plentiful food.
Song Yucheng, deputy chief engineer of East Dongting Lake National Nature Reserve, is proud of their protection work. According to him, the Eurasian spoonbills are the first to arrive at the heart of East Dongting Lake National Nature Reserve. They line up and use sideways sweeps of their beaks to filter (过滤) out tiny fish and shrimp. When they fly to another spot looking for food, people can only see the vast expanse of a white sky.
“Now the weather is also very good, the sky is very clear, with green grass, clear water and white spoonbills wandering for hunting. It’s a beautiful picture of nature,” said Song.
For the villagers living in the East Dongting Lake National Nature Reserve, their farm fields are still full of busy and active fellows after harvest because there are about 100 swans settled down there. To provide these birds with an quiet and safe environment, the local government has stopped the vehicles and visitors from entering the area.
“Firecrackers are not allowed, and loud noises are also not allowed in the surrounding area,” said Long Yong, a villager from the Hehua Village, citing the local government.
1. The birds migrate to Dongting Lake not because _____.| A．Siberia is cold at winter. |
| B．It is the nearest to Siberia. |
| C．The protection work there goes great. |
| D．The warm temperature and plentiful food. |
| A．an engineer | B．a kind of bird |
| C．migration destination | D．birds food |
| A．Weather is always good here. |
| B．More birds are coming here. |
| C．The environment is beautiful here. |
| D．It’s good to draw pictures here. |
| A．government measures |
| B．fields harvest |
| C．village life |
| D．how to observe birds in nature |
