Have you felt annoyed when a cell phone rings during the class? Something must be done to stop this. Now in New York City, USA, a rule is carried out in schools. Students can't even bring cell phones to school. Is it a good thing or not?

    Anxious parents say that cell phones are an important tool in holding New York City's families together.

    "I worry about it." said Elizabeth Lorris Ritter, a mother of a middle school kid. "It's necessary in our everyday life. We have a washing machine. We have running water, and we have cell phones."

    Many American parents think cell phones connect them to their children on buses, getting out from subways, walking through unknown places.

    "I have her call me when she gets out of school," said Lindsay Walt, a schoolgirl's mother. "No one in New York is going to let their child go to school without a cell phone."

    What about the cell phone owners, the students? Most of the students said cell phones were essential and the cell phone was like an extra hand or foot for them.

    "I feel so empty," said May Chom, 14. There is also no way to listen to music on the way to school without my phone. It will be a really, really boring trip."

    BEIJING — China's education authority will tighten the widely criticized policy of “extra credits” for the national college entrance examination to ensure a fairer chance for all exam-takers.

    Under the policy, high school students who win awards in national Olympic competitions could get "extra credits', up to 20 points for the national college entrance exam. Students with talent in sports and students who are from ethnic groups can also benefit from this policy. The extra credits have increased these students' chances of being admitted by famous universities. Some parents were found to have helped their children fabricate(伪造)award experiences or falsify qualifications to get extra credits.

    “It has harmed education equality，” the ministry said.

    Xiong Bingqi, vice-chief of the 21st Century Education Research Institute, said the policy is designed to help students who have special talents but may be weak in academic performance to have a chance to receive higher education. It will still be needed but it is time to make the rules fairer," he said.

    The ministry said it will reduce the range of competitions whose winners can get extra credits, and limit the winners, privileges.

    The new policy will apply to students who begin high school in 2011, it said.

    Chen Lei, a mother of a 10-year-old girl, said she welcomed the ministry's policy adjustment as she does not want her daughter to become an Olympic competition geek.

    But not all the Chinese parents welcomed the new policy. “It is like a thunderbolt for me. My 13-year-old son has spent so much time studying Olympic math, and participated in so many technological competitions during vacations. It is useless now,” said Dong Wen, a 43-year-old mother.

    A student said, “Many students have changed the current study plan, and they can abandon the competition. I will be interested in learning the courses which can improve my abilities.”

    Yuan Guiren, minister of education, told China Daily that the reform is an attempt to consider the overall quality of an applicant. “But the country will not stop the national college entrance  examination as it is still the most objective way to evaluate talent in China,” he said.

    China officially informed the World Trade Organization on Tuesday that it will ban the import of 24 different types of solid waste by the end of this year as part of a campaign to deal with environmental pollution and protect people's health.

    In response to growing public concerns over the potential environmental and health danger caused by the increasing amounts of solid waste imported into the country for recycling and treatment, China passed a special law in 1995 to control imports of waste materials, such as plastics, slag from steelmaking, unsorted scrap paper and discarded textile materials.

    A year later, the country published a list for solid waste imports and began implementing a permit system to control the import volumes and types of waste imported.

    However, due to the lack of effective supervision（监管）and the failure of relevant departments to fulfill their duties, solid waste imports have not been effectively controlled.

    So far, China is the world's largest importer of solid waste. According to the Ministry of Environmental Protection, China imported 7.3 million metric tons of plastic waste worth $3.7 billion in 2016, accounting for 56 percent of global imports of solid waste.

    Correct recycling of solid waste materials is an important part of the global economy, and moderate imports of scrap plastic, scrap paper and scrap rubber products, such as vehicle tires, can to some extent, make up for China's shortage of various raw materials.

    However, the lack of supervision has resulted in the country's severe soil and environmental worsening.

    Given that China's continuing efforts to push for industrial transformation and upgrading have resulted in a noticeable decline in the demand for the materials recycled from solid waste imports. It is right for the country to restrict such imports for the sake of the environment and public health, and to better adapt to the changed industrial structure.

    In the near future, we may be using our eyes to operate our smart-phones and tablets, even when it comes to playing popular games like Fruit Ninja.

    The Gaze Group has been developing eye-controlled computer technology for nearly 20years. But those devices have been firstly designed to help those with disabilities, and are very expensive.

    “After a while, we figured out that probably the best way is to go for a mass-market way,”says Gaze's Sune Alstrup Johansen. “Where everybody would have this available.”

    Johansen and some of his colleagues have formed a new company, the Eye Tribe, which is hoping to develop the technology on a mass commercial level.

    The technology works when combined with the computing device toward the user's face. After making sure of the user's eye movements, the technology is then able to easily find where a person's eyes are moving, and then allow the eyes to control a cursor (光标)

    “Our software can then determine the location of the eyes and know where you're looking on the screen to make sure what you're looking at, ”reads an explanation on the Eye Tribe site.

    There has been a gradual change toward hands-free technology in recent years, particularly in the gaming world. Recently Xbox released the Kinect device, which lets users control their Xbox and play certain games using only their hands, legs and voices. But still, most of these devices have been more of a gimmick than a practical way to use one's hands to control a mobile device. Johansen said a replaceable filter (滤光器) would be a cheap, convenient way for most consumers.

    And even as companies like The Eye Tribe work to create such a product for the average user, making the eye-controlled technology more accessible and less expensive will have similar benefits for physically disabled users.

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    A team of engineers at Harvard University has been inspired by Nature to create the first robotic fly. The mechanical fly has become a platform for a series of new high-tech systems. Designed to do what a fly does naturally, the tiny machine is the size of a fat housefly. Its mini wings allow it to stay in the air and perform controlled flight tasks.

    “It's extremely important for us to think about this as a whole system and not just the sum of a bunch of individual components,” said Robert Wood, the Harvard engineering professor who has been working on the robotic fly project for over a decade. A few years ago, his team got the go-ahead to start piecing the components together. “The added difficulty with a project like this is that actually none of those components are off the shelf and so we have to develop them all on our own,” he said.

    They engineered a series of systems to start and drive the robotic fly. “The seemingly simple system which just moves the wings has a number of interdependencies on the individual components, each of which individually has to perform well, and then has to be matched well to everything it's connected to,” said Wood. The flight device was built into a set of power, computation, sensing and control systems. Wood says the success of the project proves that the flying robot with these tiny components can be built and manufactured.

    Wood says the design offers a new way to study flight mechanics and control at insect-scale. Yet, the power, sensing and computation technologies on board could have much broader applications. “You can start thinking about using them to answer open scientific questions, you know, to study biology in ways that would be difficult with the animals, but using these robots instead,” he said. “So there are a lot of technologies and open interesting scientific questions that are really what drives us on a day to day basis.”

    It seems that electronic devices just keep getting smaller. Scientists in the United States have announced the creation of the first transistor with only two dimensions(二维).

    A transistor is a small electronic device that transfers or carries electronic current. Scientists hope these new 2D transistors will be used for building high-resolution(高分辨率)displays that need very little energy.

    Two groups of scientists created these 2D transistors. They report that the transistors are only a few atoms thick.

    Usually transistors are made with the element silicon(硅). Computer processors, memory chips, TV screens and other electronic devices contain billions of silicon-based transistors. But these very small electrical parts have certain limitations.

    Dimitris Ioannou is an electrical engineering professor at George Mason University. He says the traditional transistor has been improved as much as it can be. He adds that researchers have been looking for new materials with special features and they want transistors to be seen through and soft.

    "If the layers are very thin, the transistor can become flexible, so it doesn't have to be rigid(坚硬的), like it would be in a silicon chip. So people can think of applications like wearable electronics, television screens and other things," said Ioannou.

    These new transistors can also carry higher current. They also can move the current much faster than traditional transistors. This is important for high-definition screens.

    Dimitris Ioannou says the scientific success could prove very useful in the future. "Now, how good and how useful it will be, it's still in the stage of research, but it certainly is an advance," said Ioannou.