How much do you know about A.I. (Artificial Intelligence)?Artificial means‘man-made', and intelligence means‘the ability to learn. understand and think about things'. A.I. is about making machines think, talk, do and see. A.I. is used in many fields from、playing games to helping doctors. Many machines around us work very well because they work with the help of A.I. Man has always dreamed of building‘thinking machines'. In 1770, Wolfgand Kempelen(1 734—1804)built a wooden robot called Turk that was able to play chess(SUR). It played very well and even beat some of the top chess players of the time! Later it was found that Turk was not real. Inside the box machine was a chess player.
John McCarthy(1927—)is thought as the‘Father'of A.I. He invented the word‘A.I.'and the LISP computer programming language that many A.I. developers use today. How does A.I. work?
A.I. uses ideas from many fields:

    Computer technology has become an important part of people's life. This technology has its own special words. One well-known computer word is Google. It's the name of a popular “search engineer(引擎)” for the Internet. People use the search engineer to find information about almost any subject on the Internet. The people who started the company named it Google because in math Google is a very large number-One hundred zeros follow the number one. When you “Google” a subject, you can get a lot of information about it.
    If you Google someone, you might find that person's name on a blog (博客). A blog is short for a Web log. It's a personal Web page. Some people write blogs to express their opinions and ideas over the Internet. Some use them to share their lives with faraway friends or family. Others write blogs to help them deal with sickness, money problems or to choose movies to see or books to read. Some people add information to their blogs every day. People who have blogs are called bloggers.

    Rik-rrork. That's the sound made by frogs singing at night. You might have thought the noises were just the musical sounds of ure. You probably didn't realize that you were listening to frogs' communicating with one another. These familiar sounds are not random(随意的) but are actually meaningful to frogs.

Being Heard but Not Seen

    Frogs are good at being heard but not seen. These animals have several characters that protect them n predators (捕食者 ). One is their size. Most frogs are small, which helps them hide easily. Many frogs have coloring that allows them to hide in their environment, making it difficult for predators to find them. In addition, most frogs are active at night. So it is difficult for most animals to see them in the dark.

Small but Loud

    Frogs call to tell other frogs where they are. Their voices can be very loud. But when frogs feel the footsteps of a larger animal, they become silent.

    Many of the world's frogs live in rain forests, where there are many different animals calling to their own species (物种 ) in their own ways. Frogs need to call loudly enough to be heard through the noise in order to find other frogs.

Singing with Purpose

      Peter Narins is a scientist who studies how frogs call to one another. He has learned that frogs use their calls to help them tell friend from enemy. They sing the same notes at the same volume (音量 ) each time they call. In addition, Narins has found that frogs of the same species always sing the same patterns (模式 ). These patterns are like a code that is different from other animals' calls and difficult for others to copy. Narins also observed that timing plays a role in frog calls. Many frogs call only at a certain time of night.

More Work to Do

    Scientists want to better understand the purpose of frog calls. Studies continue to explore the details of frogs' unique communication. Being heard but not seen is one way frogs stay safe. The idea that they have found a way to survive in a dangerous world is simply amazing.

    Wouldn't it be funny if your mum said to you, "It's time for bed, honey. It's almost November!" Well, if you were a baby bear, your mother might let you know it's time to go into a deep sleep around October.

    That "deep sleep" is called "hibernation (冬眠)". When it gets cold, bears have to go into hibernation. By taking this long sleep, they can get through the cold months when the food, like berries (浆果) and nuts, cannot be found easily.

    Have you ever heard someone say that they are as hungry as a bear? Bears need to eat a lot of food before hibernating. They eat so much that they may put on forty pounds of fat in a week. During the winter "bears will live off the fat stored in their bodies. Bears are able to do that because their bodies use a lot less energy during hibernation. Their heartbeats slow down, their breathing slows down, and their body temperature drops.

    If you were going to sleep all winter, wouldn't you want to be in a safe and protected place? That is what a bear wants, so it looks for a cave to sleep in. It makes a bed using grass, leaves and twigs (嫩枝). The bear usually starts to hibernate as early as October and doesn't wake up until April or May. By the time the bear wakes up, it will have lost much of the fat. But spring time will bring much food to enjoy until it is time to hibernate again in the autumn.

    In today's world, almost everyone knows that air pollution and water pollution are harmful to people's health. However, not all the people know that noise is also a kind of pollution, and that is harmful to human health, too.

    People who work and live under noisy conditions usually become deaf. Today, scientists believe that 10% of the workers in Britain are becoming deaf because of the noise where they work. Many of the workers who print newspapers and who weave cloth (织布) become deaf. Plenty of people living near airports also become deaf. Recently it was discovered that many teenagers in America could hear no better than 65-year-old persons, because these young people like to listen to pop music and most of pop music is a kind of noise. Besides, noise which is produced by jet planes or machines will make people's life difficult and unpleasant. It can make people ill or even drive them mad.

    It is said that a continuous noise of more than 85 decibels (分贝) can cause deafness. Now the governments in many countries have made laws to control noise and make it less than 85 decibels.

    In China, the government is trying to solve not only air and water pollution problems but also noise pollution problems.

    You and I can tell one face from another easily, but can computers do the same with few mistakes? At an earlier time, many thought it was impossible, but progress in facial recognition(识别)software has made it come true. Technology is quickly catching up with the human ability to read faces.

    Some facial recognition systems use a digital picture and measure(测量) different points on the face. Measurements include the distance between the eyes, the width of the nose, the length of the jaw(下巴) line and more. A detailed map, or faceprint, of the face is developed, stored and later used as a basis for comparison and matching.

    Some government agencies, airports and banks use facial recognition technology for safety purposes. Apple and Facebook use it to provide their users with added convenience. For example, Apple's new iPhone is expected to use it to unlock the home screen. Other companies use it to help them in better recognizing their customers' needs. For example, some stores are checking into the use of the technology to catch sight of return customers. Then they can offer special deals, based on the customers' buying habits.

    In America, facial recognition is used by universities to check students' attendance. This year Welsh police used it to catch a terrorist outside a football game. In China it checks on the identities of ride-hailing drivers, permits tourists to enter some places of interest quickly and lets people pay for things with a smile.

    While some systems are used with the knowledge of the persons, others aren't, and that raises worries. For many people, however, convenience outbalances the worries, in other words, meaning that facial recognition technology is likely here to stay.