Millions of people have conditions that make walking difficult. Millions more regularly perform tough movement as part of their jobs. Wearable robotic devices called exoskeletons that help the legs move could benefit both of these groups. In laboratory settings, such devices have helped people walk faster while using less energy. But various obstacles have kept these devices from being practical for everyday use.
A research team at Stanford University led by Dr. Steven Collins has developed an exoskeleton that can rapidly adapt to the user during normal walking. The team tested how well an exoskeleton based on their model could adapt to a user. They then compared it to one based on lab measurements. Both methods wound up applying similar forces at different speeds and reduced effort similarly across a range of conditions. But the model-based adaptation took only one-quarter as long as the measurement-based adaptation.
Next, the researchers created a portable, ankle-worn exoskeleton that could be used in the real world. The exoskeleton was powered by a battery pack worn at the waist.
The team conducted tests of the device outdoors on public sidewalks. Compared with walking in normal shoes, the exoskeleton increased walking speed by 9% while expending 17% less energy on average. This is equal to the energy savings of removing a 20-pound backpack. When walking on a treadmill (跑步机) at a constant speed, users expended up to 23% less energy, equal to removing a 30-pound backpack.
“This exoskeleton personalize s assistance as people walk normally through the real world,” Collins says. “This opens the door to a much broader use of exoskeletons to assist individuals with physical impairments (损伤) and people who need to carry heavy loads,” adds co-author Dr. Scott Delp.
1. Who are exoskeletons designed for?| A．Sportsmen in a race. | B．Firefighters on a mission. |
| C．Patients with mental disabilities. | D．Doctors doing an operation. |
| A．Barriers. | B．Applications. | C．Models. | D．Backpacks. |
| A．To illustrate the advantage of exoskeletons. | B．To compare exoskeletons with normal shoes. |
| C．To give examples of different kinds of shoes. | D．To list the reasons for designing exoskeletons. |
| A．Conservative. | B．Negative. | C．Favourable. | D．Indifferent. |
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【推荐1】With nations preparing to spend billions to redesign their cities with a new focus on cycling, it’s worth remembering how the invention of the bicycle changed societies all over the world.
The person generally credited with inventing the modern bicycle was an Englishman named John Kemp Starley. In 1885, the 30-year-old inventor began experimenting in his workshop with a chain-driven bicycle featuring two much smaller wheels. When it first appeared at a bicycle show in 1886, his invention was regarded as a curiosity. But two years later, when the next model was paired with the newly invented rubber tire—which not only cushioned the ride but also made the new bicycle about 30 percent faster— the result was magic.
For a few years in the 1890s, almost anyone wanted to learn to ride, and almost everyone did. The king of Zanzibar took up cycling. So did the emperor of Russia. But it was the middle and working classes around the globe that truly made the bicycle their own. For the first time in history, the masses were able to come and go as they pleased. No more need for expensive horses and carriages.
The rocketing demand led hundreds of new companies around the world to offer their own versions. At the Stanley Bicycle Show in London in 1895, about 200 bicycle makers exhibited 3,000 models. One of the biggest makers was Columbia Bicycles, whose factory in Hartford, Connecticut, could turn out a bicycle a minute thanks to its automated assembly line (流水线)— a pioneering technology that one day would become the backbone of the automobile industry. By 1898, a third of all patent applications in the US were bicycle-related.
The bicycle even improved the human gene (基因) pool. Newly liberated young people rode around the countryside at will, meeting up in distant villages. Women were especially enthusiastic. They abandoned their troublesome skirts and took to the road in groups. Marriage records in England show a marked rise in inter-village marriages during the bicycle craze of the 1890s.
1. What can we know about John Kemp Starley’s first model?| A．It was invented in 1888. | B．It had two bigger wheels. |
| C．It did not have rubber tires. | D．It was accepted immediately. |
| A．In the 1860s. | B．In the 1870s. | C．In the 1880s. | D．In the 1890s. |
| A．The fast growing demand for bicycles. |
| B．The huge success of the bicycle industry. |
| C．The great convenience offered by bicycles. |
| D．The popularity of the newly invented bicycles. |
| A．How Have Bicycles Changed Our World? |
| B．Which Country Invented the First Bicycle? |
| C．Who Is the Inventor of the First Bicycle? |
| D．What Led to the Genetic Improvement? |
【推荐2】A robot created at Standford University is diving down to shipwrecks (沉船) in a way that humans can’t do. Known as OceanOneK, the robot allows its operators to feel like they’re underwater explorers, too.
OceanOneK resembles (像) a human diver from the front, with arms, hands and eyes that capture the underwater world in full color. The back of the robot has computers and eight multidirectional thrusters (推进器) that help it carefully explore the sites of fragile shipwrecks. When an operator at the ocean’s surface uses controls to direct OceanOneK, the robot’s touch-based feedback system causes the person to feel the water’s resistance.
The idea for OceanOneK came from a desire to study coral reefs in the Red Sea at depths beyond the normal range for divers. While OccanOneK was designed to reach maximum depths of 656 feet, researchers had a new goal:1 kilometer, hence the new name for OceanOneK. The researchers changed the robot’s body by using special foam to increase buoyancy (浮力) and fight the pressures of 1, 000 meters more than 100 times what humans experience at sea level. OceanOneK also got two new types of hands and increased arm and head motion.
During OceanOneK’s deep dive in February, team members discovered the robot couldn’t rise when they stopped for a thruster check. Flotations on the communications and power line had collapsed, causing the line to pile on the top of the robot.
OceanOneK’s descent was a success. It dropped off a memorial marker on the seabed that reads, “A robot’s first touch of the deep seafloor — A vast new world for humans to explore.” Khatib, a professor, called the experience an “incredible journey.” “This is the first time that a robot has been capable of going to such a depth, interacting with the environment, and permitting the human operator to feel that environment,” he said.
1. What can we learn about OceanOneK?| A．Its eyes are colorful. |
| B．It functions automatically. |
| C．It looks like its operator from the front. |
| D．It is remotely controlled to explore underwater. |
| A．By listing data. | B．By raising questions. |
| C．By reasoning and analyzing. | D．By presenting an argument. |
| A．Successful operation. | B．Deep diving. |
| C．Pressure resistance. | D．Flexible exploration. |
| A．A Creative Explorer | B．The Ambitious Exploration |
| C．A Self-driven Seeker — A Robot | D．A Deep-Sea Explorer — OceanOneK |
【推荐3】This new packaging material looks like conventional plastic, but it's actually made from fish waste and algae(海藻)--and unlike plastic, if it escapes into the ocean, a fish could likely eat it safely. The material, called MarinaTex, is the winner of this year's James Dyson Award.
"It began with my desire to work with waste," says Lucy Hughes, a recent graduate from University of Sussex, who once visited a fish processing factory to see the massive quantity of waste generated by the industry and find new ways to use it. She focused on fish skins and scales (鳞片). "When I had it in my hands, I realized this has got potential, she says. "It's super strong and flexible." Hughes spent months experimenting with fish waste in her kitchen, running more than 100 experiments to find a binder and a process that could hold together the proteins in the fish skins and scales. "I had a lot of failed attempts—a lot of things either were too easily broken or too soft or easily went bad," she says. She finally landed on a type of algae that can be locally got.
The material can be used to replace oil-based plastic in packaging such as bags or the half transparent windows used to show products in boxes. As her research continues, Hughes says that she'll be studying how MarinaTex works and how long it could be used to store food.
Unlike some "compostable" plastics, which need to be processed in an industrial composting facility to break down, the new material can break down in four to six weeks in a backyard compost bin. ''All the ingredients are food-grade safe," Hughes says." So, this breaks down much like a piece of food would break down."
1. Why did Hughes develop MarinaTex?| A．She wanted to look for a new plastic. |
| B．She would like fish to eat it safely. |
| C．She wanted to win James Dyson Award. |
| D．She wanted to make use of fish skins and scales. |
| A．The fish processing factory. | B．The fish waste. |
| C．Fish scales. | D．Fish skins. |
| A．It is stronger and more flexible. |
| B．It can be used as plastic bags. |
| C．It has the nutritional value for fish. |
| D．It can break down very easily and fast. |
| A．Working with Waste | B．Developing New Ideas |
| C．Making Bags from Fish Waste | D．Getting Rid of Plastic Pollution |
【推荐1】Scientists say they have discovered an earthquake-like event that can happen during a hurricane or other powerful ocean storms. They are calling it a “stormquake”. Researchers came up with this name after studying events connected with or caused by earthquakes on the sea floor during such storms. They found that the shaking can feel as strong as a magnitude 3.5 earthquake.
Intense energy from hurricanes and other severe storms can create very large waves in the ocean. These waves then “interact” in some places with solid earth under the sea to cause “intense seismic source activity,” said the leader researcher Fan, a seismologist and professor at Florida State University. “We can have seismic sources in the ocean just like earthquakes within the hard outer layer of the Earth,” he added. “The exciting part is seismic sources caused by hurricanes can last for hours or even days.”
The researchers found evidence of more than 10,000 stormquakes in coastal areas of the United States and Canada. Stormquakes were found to have happened around continental shelves or sea floors containing flat land and at lower depths, the research showed. Even with evidence of so many stromquakes happening, it was not known until recently that such events even existed. This is mainly because scientists studying earthquakes have generally considered ocean-caused seismic waves as “background noise”.
The research found that major U.S. hurricanes had produced a lot of stormquakes. One example was Hurricane Bill in 2009 in the Atlantic Ocean, which caused about 300 stormquakes as it moved north, past New Jersey. Other examples of stormquakes were Hurricane Ike in 2008 and Hurricane Irene in 2011. But the study found no evidence of stormquakes off the coast of Mexico. Also, no such activity was recorded in areas along the U.S. East Coast, starting in New Jersey, and continuing all the way down to Georgia. The team noted that even Hurricane Sandy, one of the most costly storms in U.S. history, did not cause a single stormquake. Fan says this suggests that stormquakes are strongly influenced by the physical shape of the seafloor’s surface and seafloor conditions.
Fan added that there are still “lots of unknowns” about stormquakes. But he said discovering them “suggests we are reaching a new level of understanding of seismic waves”. He hopes the discovery will lead to improved study methods for hurricanes, which in the past have mainly been observed from satellites in the sky. “Now we are able to understand the phenomenon — or at least track part of its passage — through the solid earth as well,” he said.
1. What is the distinctive feature of a stormquake?| A．Being seasonal. | B．Being destructive. |
| C．Being long-lasting. | D．Being interactive. |
| A．Because they were extremely rare on the Earth. |
| B．Because they were once neglected by scientists. |
| C．Because they generally happen in deep sea floors. |
| D．Because they are quite similar to common earthquakes. |
| A．All hurricanes don’t bring about stormquakes. |
| B．Stormquakes happen more along the East Coast. |
| C．Stronger hurricanes tend to produce stormquakes. |
| D．The sea floor’s condition changes in stormquakes. |
| A．Offering an alternative angle to research hurricanes. |
| B．Helping to predict an earthquake more accurately. |
| C．Suggesting the richness of the seismic wave field. |
| D．Preventing potential hurricanes and lessening losses. |
【推荐2】Taking a shower is relaxing. You can hum a song, daydream or think about nothing, leaving the real world behind you. But did you know that showering can also benefit your mind?
A research by Scott Barry Kaufman, a psychologist from Yale University interviewed over 3,000 people around the world. It turned out that nearly two-thirds of the interviewees said they had experienced new ideas in the shower and were more likely to have them in the shower than at work.
So why does a simple shower have such magic power? Science can explain it.
Showering can help to raise our level of dopamine( 多巴胺), a hormone closely related to our creativity. “People vary in terms of their level of creativity according to the activity of dopamine,” explained Alice Flaherty, a famous American neuroscientist. “Taking a warm shower can make us feel relaxed and therefore make the dopamine level rise and bring ‘Aha！’ moment to us.”
Besides the chemical changes, showering may give you a break from what you feel you have been stuck with. Especially when you have thought hard all day about a problem, jumping into the shower can keep you from the outside world so that you can focus on your inner feelings and memories.
Compared with sitting in front of a computer, taking a shower is something we do less frequently in our daily life. When showering, we get a fresh experience with the change of location, temperature and humidity. “New and unexpected experiences can lead to positive changes in thinking,” explained Kaufman. “Getting off the couch and jumping in the shower may create a distance and force you to think from a new point of view.”
Showering allows us to enjoy the creative juices of our minds, but it needn't just be the bathroom where you get your inspiration. For instance, Gertrude Stein, a female American writer and poet, got new ideas by driving around a farm and stopping at different cows until she found the one that most inspired her. So try to create your own way to free your mind.
1. According to the article, what changes can showering cause?| A．Bringing the terrible moment to us. |
| B．Setting the creative part of the brain free. |
| C．Leading to boredom or tiredness. |
| D．Increasing the level of dopamine. |
| A．turn one's attention inward |
| B．draw one's attention to the outside world |
| C．make an important breakthrough |
| D．many chemical changes to take place |
| A．Because taking showers happens more often. |
| B．Because taking showers can make us acquire a fresh experience, inspiring us. |
| C．Because nothing but taking showers can get our inspiration. |
| D．Because taking showers can help us try something unexpected. |
| A．encourage readers to find their own ways of getting inspiration |
| B．point out to readers that it's hard to get inspiration |
| C．explain how to link inspiration with readers' daily lives |
| D．show that creativity often comes from strange places |
【推荐3】Litterati is an app that people can use to upload information about litter they collect outside, such as its appearance, material, location, and brand. Shared online, this information contributes to building a global database of "litter maps", which can influence policy and packaging design.
"Society's failure to solve the litter problem has not been from a lack of trying. There have been public service announcements, and coastal cleanups. But I believe two components are missing from the discussion—community and data," said Jeff Kirschner, the developer of Litterati app.
Uploading pictures to an app shows users that they’re not the only ones picking up litter from public places and that others are invested in cleaning the planet, too. And the data accumulates rapidly, telling a story that helps people understand who picked up what, where, and when. In this way, people are encouraged to do more.
In San Francisco, the Litterati app was able to identify and map more than 5,000 pieces of litter in order to determine how much was caused by cigarettes specifically. Using this information the city successfully challenged a lawsuit by tobacco companies and doubled an existing cigarette sales tax, bringing in US $4 million annual revenue（税收）.
By joining forces with others using the same platform, individuals are able to take their anti-litter activism to another level. The power of combined data leads to more Extended Producer Responsibility, which is precisely what we want and advocate here—producers are forced to be responsible for dealing with their own products once consumers no longer find them useful and areincentivizedto create more environmentally friendly packaging or better policies as a result of that new responsibility.
Litterati takes a refreshingly non-judgmental approach. It shows a positive we-can-do-it attitude. Just as Jef Kirschner said, "Our goal isn't to shame. It's to provide transparency to the problem. We provide access to data and share insights with cities, citizens and businesses, guiding us all to identify the root cause of the problem, and make informed decisions of how to clean the planet."
1. What makes us fail to solve the litter problem according to Kirschner?| A．Lack of necessary data about litter. |
| B．The public's laziness in taking action |
| C．People's poor environmental awareness. |
| D．Absence of government publicity and support. |
| A．To show the influence of Litterati |
| B．To describe the details of the map |
| C．To warn people of the harm of cigarettes. |
| D．To prove the large consumption of tobacco. |
| A．Allowed. | B．Appointed. |
| C．Inspired. | D．Believed. |
| A．It can sort out litter automatically |
| B．It makes litter problem transparent. |
| C．It can shame people into not littering. |
| D．It can guide people when they collect litter |
