Self-driving vehicles will rely on cameras, sensors and artificial intelligence（AI）to recognize and respond to road and traffic conditions, but sensing is the most effective for objects and movement in the neighborhood of the vehicle. Not everything important in a car's environment will be caught by the vehicle's camera. Another vehicle approaching at high speed on a collision （碰撞）track might not be visible until it's too late. This is why vehicle-to-vehicle communication is undergoing rapid development. Our research shows that cars will need to be able to chat and cooperate on the road, although the technical challenges are considerable.

    Applications for vehicle-to-vehicle communication range from vehicles driving together in a row, to safety messages about nearby emergency vehicles. Vehicles could alert each other to avoid collisions or share notices about passers-by and bicycles.

    From as far as several hundred metres away, vehicles could exchange messages with one another or receive information from roadside units（RSUs）about nearby incidents or dangerous road conditions through 4G network A high level of A1 seems required for such vehicles, not only to self-drive from A to B, but also to react intelligently to messages received. Vehicles will need to plan, reason, strategize and adapt in the light of information received in real time and to carry out cooperative behaviours. For example, a group of autonomous vehicles might avoid a route together because of potential risks, or a vehicle could decide to drop someone off earlier due to messages received, a foreseen crowding ahead.

    Further applications of vehicle-to-vehicle communication are still being researched, including how to perform cooperative behaviour.

    Friends play an important role in our lives, and although we can't be more familiar with the fact of friendship, we often don't clearly understand how we make friends, especially with Americans. Here are some pieces of advice on making friends with Americans:

    ⒈Visiting places Americans enjoy: parties, churches, restaurants, parks and sports clubs.

    ⒉Be willing to take the first step. Don't wait for them to get close to you. Americans in China may not know you speak English. They may be uncomfortable if they can't speak your language.

    ⒊Use small talks to open the conversation. Ask them where they're from, why they come to China, etc.. Remember: Be careful not to ask personal questions about age, salary and so on.

    ⒋Show an interest in their culture, their country or their job. Americans like to talk about themselves!

    ⒌Invite them to join you for dinner or just for coffee or tea. Try to set a specific(明确的)time. Americans sometimes make general invitations like “Let's go out for dinner sometime. ” Often this is just a way to be friendly. It is not always a real invitation.

    ⒍Don't expect too much at first. Maybe they're being friendly. But maybe they want to be your good friends. It will take time to tell.

    Reading may be fundamental, but how the brain gives meaning to letters on a page has been a mystery. Two new studies fill in some details on how the brains of efficient readers handle words. One of the studies, published in the April 30 Neuron, suggests that a visual-processing area of the brain recognizes common words as whole units. Another study, published online April 27 in PLOSONE, makes it known that the brain operates two fast parallel systems for reading, linking visual recognition of words to speech.

    Maximilian Riesenhuber, a neuroscientist at Georgetown University in Washington, D. C. , wanted to know whether the brain reads words letter by letter or recognizes words as whole objects. He and his colleagues showed sets of real words or nonsense(无意义的词语)words to volunteers undergoing FMRI scans. The words differed in only one letter, such as “farm” and “form” or “soat” and “poat”, or were completely different, such as “farm” and “coat”or “poat” and “hime”.The researchers were particularly interested in what happens in the visual word form area, or VWFA, an area on the left side of the brain just behind the ear that is involved in recognizing words.

    Riesenhuber and his colleagues found that neurons(神经元)in the VWFA respond strongly to changes in real words. Changing “farm” to “form”, for example, produced as great a change in activity as changing “farm” to“coat”, the team reports in Neuron. The area responded slowly to single-letter changes in made-up words.

    The data suggests that readers grasp real words as whole objects, rather than focusing on letters or letter combinations. And as a reader's exposure to a word increases, the brain comes to recognize the shape of the word. “Meaning is passed on after recognition in the brain”, Riesenhuber says.

    The researchers don't yet know how longer and less familiar words are recognized, or if the brain can be trained to recognize nonsense words as a unit.

    Feeding a crowd of hundreds doesn't make Kenny Seals-Nutt nervous.

    In fact, he loves being in the kitchen.

    By the time Kenny, 16, reached his third year of high school in Charlotte, US, he had become vice president of his school's cooking club.

    Kenny said he developed his love of cooking by watching his grandmother, who owned a business.

    And at the age of 5, he cooked his first dish. Taking it to school for lunch, he warmed it up in the school's microwave, while the other kids ate their sandwiches.

    "I love to eat, and it started to become more fun to cook than to have food prepared for me," he said.

    Cooking came easy to Kenny, and he enjoyed adding new ingredients (原料) into common dishes. "It started with a passion (热情) and I wanted to know more," he said.

    Last summer, Kenny put his skills to the test by working with his grandmother to cater his uncle's wedding. Kenny added new changes to the traditional (传统的) dishes that his grandma had prepared.

    Chef Frederick Mookie Hicks, owner of a catering business, said Kenny's success comes from his ability (能力) to multitask (多任务) in the kitchen.

    "He's so enthusiastic (热情的) about cooking that he doesn't let anything stop him," Hicks said.

    Researchers at the University of York in England published their findings on facial recognition that, on average, people can remember as many as 5,000 faces.

    There have been many studies recently on facial recognition technology. But the authors of this study say theirs is the first time that scientists have been able to put a number to the abilities of humans to recognize faces. Rob Jenkins, leader of the research, said the researchers' study centered on "the number of faces people actually know." and were not able to discover whether there is a "limit on how many faces the brain can handle."

    Jenkins said the ability to tell individual people apart is "clearly important." In today's modern world of big cities, we meet and deal with thousands of people. The study suggests our facial recognition abilities help us to deal with the many different faces we see on the screens, as well as those we know. The results of the study give a baseline for comparing the "facial vocabulary" of humans with facial recognition software.

    Today, facial recognition technology is used in many ways, including by law enforcement agencies to prevent crime and violence. Governments use it to keep secret areas secure and, in extreme cases, control populations. Some governments use the software to watch people and find out where they go and what they do. Even Facebook uses facial recognition. For example, when you name a friend, Facebook technology may recognize the person's face from a different picture you had shared before.

    For the human study, people spent one hour writing down as many faces from their personal lives as possible. At first, they found it easy to come up with many faces. But by the end of the hour, they found it harder to think of new ones. Their change in speed let the researchers estimate when they would have run out of faces completely. 1,000 to 10,000 faces remembered. People who took part in the study were also shown thousands of photographs of famous people. Researchers asked them which ones they recognized. To make sure they knew these people, researchers required them to recognize two different photos of each famous person. The results showed that the participants knew between 1,000 and 10,000 faces.

    How do they explain such a wide range? Jenkins said one explanation may be that some people have a natural ability for remembering faces. "There are differences in how much attention people pay to faces and how well they process the information." Also it could be because of different social environments. Some people may have grown up in more populated places. So, they may have had more social contact throughout their lives.

    Researchers think age may be an interesting area for further research. “It would be interesting to see whether there is a peak age for the number of faces we know”, Jenkins said. He said it is possible that we gather more faces throughout our lifetime. But, he added, there also may be an age at which we start to find it harder to remember all of those faces.

    I am afraid of heights but two summers ago I climbed to a high place. Most of our high school had come along on a day trip to a beautiful beach village in Peru. After eating our lunches, many of us wanted to make the climb to an area around the village.

    Do I turn back? "Yes!" Will I regret (后悔))it later? I really want to get to the top, but... At last, I decided at least to have a try.

    My friend Tom was in front of me. Then, suddenly, he slipped (滑倒))and was about 10 feet back! My heart was beating faster until he stopped himself. Knowing that my friend Seth would be right behind me, I began the climb. I was soon past the first challenge safely, but not feeling much better about the rest of the climb. Looking down, I saw rocks everywhere. My breathing sped up, and my heart beat even faster, growing loud in my ears.

    My friends kept climbing. But they did not forget me. Someone was always behind me to help hold my feet when necessary, and someone else was always in front to offer a hand up. With friends helping me by words and actions, I slowly gained ground.

    Then we came to the worst part. The climb looked very close to vertical (垂直的). To me, the wise choice was to go back down. Melody encouraged me to go on and she made it safely first. I stopped, unsure of my footing. "You can do it, Jean! I'm right here," Melody called. She waited patiently, not asking me to hurry. I took a few deep breaths and kept climbing.

    With no more mistakes, we came to the top finally. I was dirty and tired. But it didn't matter. I was at the top! I had never felt so alive.