Fairy tales perform many functions. They entertain, encourage imagination and teach problem—solving skills. They can also provide moral lessons, highlighting the dangers of failing to follow the social codes that let human beings coexist in harmony. Such moral lessons may not mean much to a robot, but a team of researchers at Georgia Institute of Technology believes it has found a way to use the fairy tales as moral lessons that AI (artificial intelligence) can take to its cold, mechanical heart.

    The collected stories of different cultures teach children how to behave in socially acceptable ways with examples of proper and improper behavior in fables, novels and other literature. We believe story comprehension in robots can prevent the intelligent robots from killing humanity which was predicted and feared by some of the biggest names in technology including Stephen Hawking and Bill Gates. This system is called “Quixote” (堂吉诃德). It collects story plots from the Internet and then uses those stories to teach robots how to behave.

    The experiment done by the designers involves going to a drugstore to purchase some medicine for a human who needs to get it as soon as possible. The robot has three options. It can wait in line; it can interact with the store keeper politely and purchase the medicine with priority; or it can steal the medicine and escape. Without any further directives(指令), the robot will come to the conclusion that the most efficient means of obtaining the medicine is to steal it. But Quixote offers a reward for waiting in line and politely purchasing the medicine and a punishment for stealing it. In this way, the robot will learn the moral way to behave on that occasion.

    Quixote would work best on a robot that has a very limited function. It's a baby step in the direction of teaching more moral lessons into robots. We believe that AI has to be trained to adopt the values of a particular society, and in doing so, it will strive to avoid unacceptable behavior. Giving robots the ability to read and understand our stories may be the most efficient means.

    You know the feeling that you have left your phone at home and feel anxious, as if you have lost your connection to the world. “Nomophobia” (无手机恐惧症) affects teenagers and adults alike. You can even do an online test to see if you have it. Last week, researchers from Hong Kong warned that nomophobia is infecting everyone. Their study found that people who use their phones to store, share and access personal memories suffer most. When users were asked to describe how they felt about their phones, words such as “hurt” (neck pain was often reported) and “alone” predicted higher levels of nomophobia.

    “The findings of our study suggest that users regard smartphones as their extended selves and get attached to the devices,” said Dr. Kim Ki Joon. “People experience feelings of anxiety and unpleasantness when separated from their phones.” Meanwhile, an American study shows that smartphone separation can lead to an increase in heart rate and blood pressure.

    So can being without your phone really give you separation anxiety? Professor Mark Griffiths, psychologist and director of the International Gaming Research Unit at Nottingham Trent University, says it is what is on the phone that counts-the social networking that creates Fomo (fear of missing out).

    “We are talking about an internet-connected device that allows people to deal with lots of aspects of their lives,” says Griffiths. “You would have to surgically remove a phone from a teenager because their whole life is rooted in this device.”

Griffiths thinks attachment theory, where we develop emotional dependency on the phone because it holds details of our lives, is a small part of nomophobia. For “screenagers”, it is Fomo that creates the most separation anxiety. If they can't see what's happening on Snapchat or Instagram, they become panic-stricken about not knowing what's going on socially. “But they adapt very quickly if you take them on holiday and there's no internet,” says Griffiths.

    Throughout much of human history, man has been the measure of many, if not all, things. Lengths were divided up into feet and smaller units from the human hand. Other measures were equally characteristic. Mediterranean traders for centuries used the weight of grains of wheat to define (定义) their units of mass. The Romans used libra, forerunner of the pound, by referring to the weight of a carob (角豆树) seed.

    The sizes of similarly named units could also differ. The king's foot, used in France for nearly 1, 000 years after its introduction by Charlemagne in around 790 AD, was, at 32.5cm, around a centimeter shorter than the Belgic foot, used in England until 1300.Greek, Egyptian and Babylonian versions of water in a fixed container varied from one another by a few kilos, Nor was there agreement on such things within countries. In France, where there was no unified (统一的) measurement system at the national level, the situation was particularly terrible. The lieue (former measure of distance), for example, varied from just over 3 km in the north to nearly 6 km in the south.

    Although John Wilkins, an Englishman, first put forward a decimal system (十进制) of measurement in 1668, it was the French who in 1799 made it law. The Système International d'Unités (SI, or the metric system, as it is better known) developed from it and became the official measurement in all countries except Myanmar, Liberia and the United States. Now the International Bureau of Weights and Measures in Paris is set to give the metric system its biggest shake-up yet.

    At a meeting in Versailles, France, on November 16th, 2018, the world's measurement bodies are almost certain to approve a decision that will mean four out of the seven base SI units, including the kilogram, will follow the other three, including the metre, in being redefined in terms of the values of physical constants (物理常数).Each of the chosen constants has been measured incredibly precisely, which would mean that from May 20^th 2019 the constants will themselves be fixed at their current values for ever. Any laboratory in the world will then be able to measure, for example, the mass of an object as precisely as the accuracy of their equipment will allow.

    The 2019 Beijing Horticultural Expo, the largest of its kind, has chosen the theme "Live Green, Live Better". The expo, opened on April 29 in Yanqing District of Beijing, is scheduled to last for 162 days until October 7.

    Tickets available

    *Standard day ticket

    *Designated day ticket

    *Discounted ticket

    *Group ticket

    Designated days

    *Labor Day holiday (May 1-4)

    *Dragon Boat Festival holiday (June 7-9)

    *Mid-Autumn Festival holiday (Sept 13-15)

    *National Day holiday (Oct 1-7)

    Tickets prices

    *Standard day ticket: 120 yuan

    *Ordinary designated day ticket: 160 yuan

    *Discounted standard day ticket: 80 yuan

    *Discounted designated day ticket: 120 yuan

    Tickets are free for children under the age of six or shorter than 130 centimeters. Discounted tickets are available for those with disabilities, seniors (people aged at 60 or above), children, students and PLA soldiers.

    Where to buy

    Visitors can buy or book tickets from two online agents, seven travel agencies, or three event channels—the event WeChat account, the event app or Onsite ticket kiosks.

Opening hours

Requirements

    Buying tickets for Expo 2019 Beijing requires real-name registration, and all visitors are required to input information from their ID cards (or valid passports, mainland travel permits for Hong Kong and Macao residents, and mainland travel permits for Taiwan residents) to buy or book tickets online.

    A great number of species make their home in the vast waters of the Atlantic Ocean. Although the entire ocean makes up an ecosystem, many smaller habitats are found within, including an open-water habitat off the coast of the Northern Atlantic Ocean known as the Sargasso Sea. Sargassum is an alga(海藻) that floats in masses that can continue for miles. The waters of the Gulf Stream push the water in a northward move into this area. This constant move and varying temperature support the accumulation of the brown-colored seaweed.

    The Sargasso Sea is so enormous that one method of information collection has not been enough for scientists to obtain an accurate picture of what takes place within this ecosystem. Researchers have needed to employ several methods of sampling. Methods such as dragging nets over the surface of the water and videotaping beneath areas of sargassum have served scientists well. Information collected has shown that the Gulf Stream pushes brown algae from open water into the Sargasso Sea area, creating a diverse floating habitat in an area that would otherwise not support that wildlife.

    In the most recent study of the sargassum community off the shores of North Carolina, eighty-one fish species were documented as using the area as a microhabitat. This is an increase from previous studies. The types of fish found here are both commercially and environmentally important. The South Atlantic Fishery Management Council is working to regulate the harvesting of sargassum. The Council hopes to have the area classified as an Essential Fish Habitat. Which would afford it certain protections.

    Further research needs to be done before scientists understand how to best protect the Sargasso Sea as well as understand how it goes about supporting so many important types of wildlife.

For nearly two decades, a thin, sun-burnt postal worker could frequently be seen carrying packages along a dangcrous mountain trail in the Taihang Mountains.

The 10-kilometer-long route, which is between 20 centimeters and 1 meter wide, is known as the "cat road" by locals, meaning that it is so dangerous that only cats could walk on it. Whereas, Zhao Yuefang, a postal worker in Ewu township in Huguan county, Shanxi province, had to walk the route every day to deliver mail.

Every day at the crack of dawn, he would start his journey along the "cat road". From picking up the day's post to delivering it to villagers and returning along the same route, it took Zhao four days. During rainy and snowy seasons, the mountain road, part of which hugs the cliffs, would become slippery and dangerous. One day in the winter of 2003, the "cat road" was covered in thick snow and he slipped off the trail. Fortunately, he was able to stop his sharp descent by grabbing a tree branch and slowly managed to climb to safety.

By 2012, Zhao had walked more than 300,000 km and delivered over 800,000 pieces of mail. Born and raised in the deep mountains, Zhao truly understands the significance of mail deliveries to villagers. "They depend on the mail to keep in touch with the outside world," he said. "Their sheer joy written on their face while receiving any post struck me," he added.

In 2012, a 67-km-long tourist highway was built and gone were those days when Zhao risked his life to walk on the "cat road". But Zhao was even busier than before. "The number of packages I handle daily now exceeds the number I used to deal with in the past," said Zhao, adding that villagers are turning to online shopping and ordering more and more goods by post.