Why do human beings still risk their lives under ground and doing one of the dirtiest and most dangerous jobs in the world? It is an increasingly urgent question, given the recent mining accidents in Sago, W. Va and Huntington, Utah. A small group of engineers and robotics experts look forward to a day in the not-too-distant future when robots and other technology do most of the dangerous mining work.

    Robotic technology, in particular, holds much promise, McAteer says, especially when it comes to mapping mines and rescuing trapped miners — the special operations of the mining industry.

    One of the first mining robots was developed five years ago at Carnegie Mellon University's Robotics Institute. It was called Groundhog. It used lasers(激光器) to “see” in dark tunnels and map abandoned mines—some of the most dangerous work in the business.

    The latest design is called Cave Crawler. It's a bit smaller than Groundhog, and even more advanced. It can take photos and videos and has more sensors that can detect the presence of dangerous gases. Incredibly, the robot has a real sense of logic. If it comes across an obstacle it gets momentarily confused. It has to think about what to do and where to go next. Sometimes it throws a fit just like a real person.

    The greatest problem, though, is cost. The money of the earliest research project was provided by the government, but that money had dried up, and it's not clear where future money will come from. Partly for that reason, and partly because of advances in safety, mining is not nearly as dangerous as it was in the past. Since 1990, fatalities(致命性) have declined by 67% and injuries by 51% , according to the National Mining Association.

    Some experts predict that robots in mines will serve much of the same function that they do in the automotive industry. The robots do the most boring and dangerous jobs，but won't get rid of the need for human workers.

    Wouldn't it be wonderful to travel to a foreign country without having to worry about the headache of communicating in a different language?

    In a recent Wall Street Journal article, technology policy expert Alec Ross argued that, within a decade or so, we'll be able to communicate with one another via small earpieces with built-in microphones. That's because technological progress is extremely rapid. It's only a matter of time. Indeed, some parents are so convinced that this technology is imminent that they're wondering if their kids should even learn a second language.

    It's true that an increase in the quantity and accuracy of the data loaded into computers will make them cleverer at translating “No es bueno dormir mucho” as “It's not good to sleep too much.” Replacing a word with its equivalent (同义词) in the target language is actually the “easy part” of a translator's job. But even this seems to be a discouraging task for computers.

    It's so difficult for computers because translation doesn't—or shouldn't—involve simply translating words, sentences or paragraphs. Rather, it's about translating meaning. And in order to infer meaning from a specific expression, humans have to interpret a mass of information at the same time.

Think about all the related clues that go into understanding an expression: volume, gesture, situation, and even your culture. All are likely to convey as much meaning as the words you use.

    Therefore, we should be very skeptical of a machine that is unable to interpret the world around us. If people from different cultures can offend each other without realizing it, how can we expect a machine to do better? Unless engineers actually find a way to breathe a soul into a computer, undoubtedly when it comes to conveying and interpreting meaning using a natural language, a machine will never fully take our place.

    One afternoon I toured an art museum while waiting for my husband to finish a business meeting.I was looking forward to a quiet view of the art works.

    A young couple viewing the paintings ahead of me chatted nonstop between themselves.I watched them a moment and decided the wife was doing all the talk.I admired the husband's patience for putting up with her continuous talk.Distracted by their noise,I moved on.

    I met with them several times as I moved through the different rooms of art.Each time I heard her constant burst of words,I moved away quickly.

    I was standing at the counter of the museum gift shop making a purchase when the couple came near to the exit.Before they left,the man reached into his pocket and pulled out a white object.He extended it into a long stick and then tapped his way into the coatroom to get his wife's jacket.

    “He's a brave man.”The clerk at the counter said,”Most of us would give up if wewere blinded at such a young age.During his recovery he made a promise that his life wouldn't change. So, as before,he and his wife come in whenever there's a new art show.”

    “But what does he get out of the art?”I asked,“He can't see.”

    “Can't see?You're wrong.He sees a lot.More than you or I do.”The clerk said,“His wife describes each painting so he can see it in his head.”

    I learned something about patience,courage and love that day.I saw the patience of a young wife describing paintings to a person without sight and the courage of a husband who would not allow blindness to change his life.And I saw the love shared by two people as I watched this couple walk away hand in hand.

    At times my mom has been uncomfortable seeing some quality in me. For example, when I was 12, I went to Puerto Rico all by myself to stay with my grandmother for the summer. My mom was extremely nervous about it. She kept telling me how things were different in Puerto Rico, to always put on sunscreen, not to wander away from my grandmother, and other warnings. She helped me pack and did not leave the airport until she saw my plane take off.

    But despite her worries, she let me go on my own. As I moved into my teens, she continued to give me space to grow and learn, even when it might have been difficult for her. When I reached my senior year, I decided to move away for college. Once again I found that I differed from my peers: while many of them wanted to stay close to home, I couldn't wait to be out in the world on my own. While my mom may not have been happy at the thought of my going away, she was supportive and excited for me.

    One big thing I realized during my senior year, as my mom granted me more freedom, was that she actually believes in me and trusts me. That means a lot. Most of my life, and especially when I was little, the main person I tried to impress in my schoolwork or other things was my mother. I knew she expected nothing but the best from me. Sometimes it was hard to live up to her standards: getting a single B on my report card would make me feel bad because I knew she wanted me to have all A's.

    I know that her high standards have helped me stay focused on what's important, like education, and made me who I am. I am thankful for her support and involvement in my life. Most of all I respect her. She is the strongest woman I know and that's why I have turned out so strong and independent.

    Can dogs and cats live in perfect harmony in the same home? People who are thinking about adopting a dog as a friend for their cats are worried that they will fight. A recent research has found a new recipe of success. According to the study, if the cat is adopted before the dog, and if they are introduced when still young (less than 6 months for cats, a year for dogs), it is highly probable that the two pets will get along swimmingly. Two-thirds of the homes interviewed reported a positive relationship between their cat and dog.

    However, it wasn't all sweetness and light. There was a reported coldness between the cat and dog in 25% of the homes, while aggression and fighting were observed in 10% of the homes. One reason for this is probably that some of their body signals were just opposite. For example, when a cat turns its head away it signals aggression, while a dog doing the same signals submission.

    In homes with cats and dogs living peacefully, researchers observed a surprising behaviour. They are learning how to talk each other's language. It is a surprise that cats can learn how to talk ‘Dog', and dogs can learn how to talk ‘Cat'.

    What's interesting is that both cats and dogs have appeared to develop their intelligence. They can learn how to read each other's body signals, suggesting that the two may have more in common than we previously suspected. Once familiar with each other's presence and body language, cats and dogs can play together, greet each other nose to nose, and enjoy sleeping together on the sofa. They can easily share the same water bowl and in some cases groom (梳理) each other.

    The significance of the research on cats and dogs may go beyond pets ─ to people who don't get along, including neighbors, colleagues at work, and even world superpowers. If cats and dogs can learn to get along, surely people have a good chance.

Big Stuff

Do you know what is the tallest building in the world and where the tallest Ferris wheel is? Have you heard of the world's steepest roller coaster? Have you seen the biggest monster truck? Here are some of the most huge things on Earth.

A Towering Achievement

Burj Khalifa, a tower in Dubai, United Arab Emirates, is the world's tallest structure. The 162-story building, which opened in 2010, stands over 2,717 feet tall. Seen from above, the tower has a Y-shaped design. Its three tall, narrow wings are joined in the middle. Like the legs of a tripod （三脚架）, each wing is supported by the other two.

A Wheel Winner

About 15 miles from the world's tallest building stands the world's tallest Ferris wheel, Ain Dubai. Also called an observation wheel, Ain Dubai stands 820 feet tall. Each of the 48 cabins can carry 40 people for spectacular views of Dubai, United Arab Emirates. Before construction, support columns had to be driven 115 feet down through the earth to reach bedrock.

Extreme Ups and Downs

The world's tallest roller coaster is Kingda Ka at Six Flags Great Adventure. At 456 feet, the peak of the ride towers over nearby Jackson, New Jersey. A 500-foot-tall crane was needed to place the final section at the top. Like many weight-bearing structures, the tower makes use of the most stable geometric （几何的） shape, the triangle.

A Monster of a Truck

Designed and built by business owner Bob Chandler, Bigfoot 5 has held the record for the world's biggest monster truck since 

1986. Other trucks, including Bigfoot models, have been designed to perform better in competitions. But Bigfoot 5 still stands above the crowd, thanks to its 10-foot-tall tires. The tires were originally designed for equipment that drives on Alaska's snowy tundra.