A device that stops drivers from falling asleep at the wheel is about to undergo testing at Department of Transport laboratories and could go on sale within 12 months.

    The system, called Driver Alert, aims to reduce deadly road accidents by 20%—40% that are caused by tiredness. Airline pilots can also use it to reduce the 30% of all pilot-error accidents that are related to fatigue.

    Driver Alert is based on a computerized wristband (腕带). The device, worn by drivers or pilots gives out a sound about every four minutes during a car journey. After each sound the driver must respond by squeezing the steering wheel (方向盘). A sensor in the wristband detects this pressing action and measures the time between the sound and the driver's response.

    Tiredness is directly related to a driver's response time. Usually, a watchful driver would use about 400 milliseconds to respond, but once that falls to more than 500 milliseconds, it suggests that the driver is getting sleepy.

    In such cases the device gives out more regular and louder sounds, showing that the driver should open a window or stop for a rest. If the driver's response continues to slow down, the sounds become more frequent until a nonstop alarm warns that the driver must stop as soon as possible.

    The device has been delivered to the department's laboratories for testing. If these tests, scheduled for six months' time, are successful, the makers will bring the product to market within about a year.

    Recently a new study has been carried out. It shows students who write notes by hand during lectures perform better on exams than those who use laptops.

    Students are increasingly using laptops for note-taking because of speed and legibility (清晰度). But the research has found laptop users are less able to remember and apply the concepts they have been taught.

    Researchers performed experiments that aimed to find out whether using a laptop increased the tendency to make notes “mindlessly” by taking down word for word what the professors said.

    In the first experiment, students were given either a laptop or pen and paper. They listened to the same lectures and were told to use their usual note-taking skills. Thirty minutes after the talk, they were examined on their ability to remember facts and on how well they understood concepts.

    The researchers found that laptop users took twice as many notes as those who wrote by hand. However, the typists performed worse at remembering and applying the concepts. Both groups scored similarly when it came to memorizing facts.

    The researchers' report said, “While more notes are beneficial, if the notes are taken mindlessly, as is more likely the case on a laptop, the benefit disappears.”

    In another experiment aimed at testing long-term memory, students took notes as before but were tested a week after the lecture. This time, the students who wrote notes by hand performed significantly better on the exam.

    These two experiments suggest that handwritten notes are not only better for immediate learning and understanding, but that they also lead to superior revision in the future.

    Everglades National Park (大沼泽地国家公园) is located in the state of Florida. It is the largest wilderness in the entire country and makes up 25% of the wetlands in the state. The park is home to several rare and endangered species. It is also the third largest national park in the US, after Death Valley and Yellowstone. Each year, about 1 million tourists visit the park. On a global level, it has been announced as a World Heritage Site.

    Unlike most other national parks, Everglades National Park was created to protect an ecosystem (生态系统) from damage. In 1947, President Harry Truman spoke at the official opening of Everglades National Park, saying the goal of creating the park was to protect forever a wild area that could never be replaced.

    10,000 different islands make up Everglades National Park. Each of these islands is lived by natural wildlife. The Everglades is home to about 15 species that are endangered. In addition, more than 350 bird species and 300 species of fresh and saltwater fish live within the park. The Everglades is also home to 40 species of mammals and 50 reptile species.

    There are many ways to explore the Everglades. Visitors can see alligators (短吻鳄) while hiking the Anhinga Trail. The Everglades is one of the only places on Earth where freshwater alligators and saltwater crocodiles live in the same area. Visitors using airboats are likely to see large groups of birds. Some visitors might enjoy riding bicycles through Shark Valley. Others may want to move slowly through waters where they can see insects and wildlife closely.

    According to experts, changes to the Everglades are becoming a danger to several different kinds of wildlife. They say it is a result of actions the US government began more than 50 years ago, and settlers began even earlier.

    TED is a non-profit organization devoted to Ideas Worth Spreading. It started out (in 1984) as a conference bringing together people from three worlds: Technology, Entertainment, and Design. Since then it has stepped into more and more fields. It includes two annual ( 年度的) conferences-the TED Conference on the North American West Coast each spring, and the TED Global Conference in Edinburgh UK each summer, which bring together the world's most excellent thinkers and doers, who are challenged to give the talk of their lives ( in 18 minutes or less).

    On ted.com, we make the best talks and performances from TED and partners available to the world, for free. More than 1, 200 TED talks are now available,' with more added each week, which cover almost all topics from science to business to global issues- in more than 110 languages. They really help share ideas in communities around the world.

    We believe in the power of ideas to change attitudes, lives and eventually, the world. So we' re building here a clearinghouse (信息交流中心 ) that offers free knowledge and inspiration from the world's most inspired thinkers, and also a community of curious souls to engage with ideas and each other. Have an idea? We want to hear from you.

    Today, TED is best thought of as a global community. It's a community welcoming people from every field and culture who seek a deeper understanding of the world.

    Want to follow TED? Here are the ways to connect:

    Get TED news and conference coverage ( 新闻报道) on the TED Blog.

    Follow TED on Twitter:

    @TED News for all TED news and information

    @TED Talks for daily TED Talk release only

    See photos from TED events on Flicker.

    Do you often dream at night? How do you feel when you dream? Is it useful to our health? “Dreams may be more important than sleep, and we all need to dream,” some scientists say.

    Dreams take up about one quarter of our sleeping time. People have several dreams each night. Dreams are like short films. They are usually in colour. Some dreams are like old films. They come to us over and over again. That may be because the dreamer is worrying about something. Dreaming may be a way of trying to find an answer. Some people get new ideas about their work from dreams. They may have been thinking about their work all day. These thoughts can carry over into dreams.

    Sometimes we wake up with a good feeling from a dream. But often we can't remember the dream. Dreams can disappear quickly from memory.

    Too much dreaming can be harmful. The more we sleep, the longer we dream. The mind is at work when we dream. That is why we may have a long sleep and still wake up tired.

High-Wire Act

    Mickey Wilson had been on the mountain only a few seconds when he heard the scream. Wilson, 28 years old, had just gotten off the cable car (索道缆车) at the Arapahoe Basin Ski Area in Keystone, Colorado, along with his friends Billy Simmons and Hans Mueller. Their friend Richard had been on the cable car ahead of them, but when the men reached the top of the lift, he had disappeared. The men walked toward the source of the scream and found skiers stopped on the slope, pointing to the cable car. And then the friends screamed too.

    "Oh, Richard!" yelled Mueller.

    When Richard had tried to jump off the cable car, his backpack had been caught in the chair, which then dragged him back down the hill. In the process, the backpack belt twisted around his neck, making him breathless. Now Richard's body was swinging four feet above the snow. The cable car operator had quickly stopped it, and the friends kicked off their skis and ran toward the scene. They made a human pyramid to try to reach Richard, but the unconscious man was too far off the ground. With the clock ticking, Wilson ran to the ladder of a nearby lift tower. Scared skiers watched as he struggled the 25 feet. After he reached the top, Wilson's first challenge was to climb onto the two-inch steel cable that held the chairs. He handled the balance and height bravely, but he knew he could not walk on the cable. Therefore, he calmed down and sat over it and then used his hands to pull himself to Richard quickly. Wilson's greatest fear wasn't that he'd fall, but that he wouldn't reach Richard. "This was life or death," he said.

    When he reached Richard's chair, Wilson swung a leg over the cable and attempted to drop down onto it. But as he did that, his jacket caught on the movable footrest, which was in the up position. The footrest began to slide down, with Wilson attached. But before that could happen, he managed to free himself and reached Richard.

    Fortunately, the ski patrol (巡查) had gathered below and performed emergency treatment on Richard, who had been hanging for about five minutes, then skied him down to an ambulance.

    That night, Richard called from the hospital to express his thanks to Wilson, his other friends and the workers at the Arapahoe Basin Ski Area.