How long has 3-D technology been around? Most of us might think of crowds of teenagers in a 1950's movie house watching Bwana Devil in 3-D. But 3-D technology made its first appearance on the scene in 1838 with the first stereoscope(体视镜). And the first actual 3-D movie was a 1903 film called Le Ariveed'un Train.

    Although it has such a long history, the technology has still remained based on one simple principle—to make 3-D effects you must find a way to project two slightly different pictures to each eye. Modern 3-D technology works by rapidly flickering(闪动)two versions of the movie and projecting them onto each eye. The brain does the rest of the work, combining the two pictures together into one and giving the show the appearance of depth, the third dimension.

    But does this exposure, especially long exposures, cause harm to the child's developing brain and visual system? Unfortunately, long-term studies on new flicker digital 3-D technology and children aren't yet available. We do not know if regular or daily 3-D viewing over years affects the developing visual system, although older 3-D methods basically do the same thing and are not considered harmful.

    The question of possible harm in modern 3-D use in TV is really based on two facts: the amount of time children will now be watching 3-D TV each day and the sensitivity some children show in reaction to 3-D viewing. It is difficult to make actual lab studies of longer term 3-D viewing in children because of the possible harm of the experiment. Researchers will have to wait until 3-D TV technology is already in the marketplace for a number of years, then check heavy 3-D TV watchers and compare them with non-watchers.

    With a 3-D television technology in the home, we will soon be able to answer the question of whether or not longer and more frequent periods of 3-D exposure cause more changes in the visual system. We may find that the bigger problem is the introduction of a new technology that leads to even more time spent on TV rather than playing outdoors.

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Schedule a Tour

    University of South Carolina （USC) is famous for its warm southern hospitality（好客）. Schedule a visit and feel it in person. Our walking tours are led by current students, called University Ambassadors, who are looking forward to telling you what it's like to live and study in USC. Our walking tours run Monday through Friday and most are around 2 hours. The university will be closed on Tuesday, July 4, 2017 in observance of the holiday. We welcome your visit year round and will be ready for you, rain or shine. Please refer to the list below to determine which tour is best for you and remember to book at least two weeks in advance.

    A day in the life of 18-year-old David Lanster is full of typical teenage stuff: school, baseball practice, homework. And then he starts cooking.

    “Some nights I'm up until I am making pies, or even later if we're braising (蒸) beef,” said the student at Ransom Everglades High School in Florida, US.

    For the past year, Lanster and Kelly Moran, his classmate, have been hosting fancy dinner parties at Lanster's parents' home. Their meals have 17 courses and are all made by them.

    Their guests used to give them gifts to thank them, until the pair decided to do something nice for charity (慈善).

    “We got some really great Miami Heat tickets, a nice watch, and many kitchen gadgets (小物件),” Lanster said. “But we wanted to make this something positive for people other than us.”

    Lanster and Moran focused on Common Threads, a charity that aims to teach kids in poor communities (社区) to cook and make healthy eating choices.

    The young cooks ask their guests to give however much they want as payment for their meals. It all goes to Common Threads because Lanster's parents cover their food costs. After their last 12-person event, Lanster and Moran gave $1,600 (10,600 yuan) to the charity.

    Now, they're taking their show out of the kitchen and on the road. Lanster and Moran have started to organize private dinner parties with a similar model: the host pays for the ingredients, and the guests make a donation to a charity of their choice.

    Without formal (正规的) training, Lanster said he had been interested in cooking since he helped his mom in the kitchen when he was very young. He learned how to cook by reading cookbooks and watching TV programs.

    Outside the kitchen, the two are busy preparing their college applications.Neither is sure what they will do in the future, but they've promised their parents that they'll leave professional cooking alone until they finish school.

    Dunster City Library provides a wide range of Library Special Needs Services for people who don't have access to our library service in the usual way. As long as you live in Dunster City, we'll provide a wide range of library services and resources including:

    Large printed and ordinary printed books

    Talking books on tape and CD

    DVDs and music CDs

    Magazines

    Reference and information requests

    Home delivery service

    Let us know what you like to read and we will choose the resources for you. Our staff will deliver the resources to your home for free. We also provide a service where we can choose the resources for you or someone instead of you choose the things from the library. You can also choose the resources you need personally. Talking books and captioned videos

    The library can provide talking books for people who are unable to use printed books because of eye diseases. You don't have to miss out on reading any more when you can borrow talking books from the library. If you have limited hearing which prevents you from enjoying movies, we can provide captioned videos for you at no charge. Languages besides English

    We can provide books in a range of languages besides English. If possible, we will request these items from the State Library of NSW, Australia.

How to join?

    Contact the Library Special Needs Coordinator to register in advance or discuss if you are eligible (合适的)for any of the services we provide—Tuesday, Wednesday and Thursday 9am—5pm on 4297 2522 for more information.

    California has become the first U.S. state to approve plans to require newly-built homes to include solar equipment.

    The state's Energy Commission voted 5-0 to approve the new rules, which are to take effect in 2020. The rules will deal with most newly-built residential (住宅的) buildings up to three stories high.

    The move is California's latest step aimed at reaching renewable energy targets and reducing greenhouse gas emissions.

    California has set a goal of filling half of its electricity needs with renewable energy by 2030. Officials said they had reached 30 percent by the end of 2017. The state's Governor, Jerry Brown, plans to hold an international climate meeting in September.

    ①The Energy Commission said the cost of adding solar equipment to a single-family home would be about $9,500. But, the group added that homeowners would save at least $19,000 in energy costs over 30 years.

    Robert Raymer is the technical director for the California Building Industry Association. He says the action is a step forward for the wider use of solar power in the U.S. "You can bet every other of the 49 states will be watching closely to see what happens," he told the Associated Press.

    ②Solar companies praised the new requirements, which officials have said will likely raise demand for solar equipment in California by 10-15 percent.

    The Solar Energy Industries Association called it a "historic decision for the state and the U.S." It estimated the action would produce "huge economic and environmental benefits," including bringing tens of billions of dollars into California.

    ③Some legislative and community leaders argued that Californians cannot afford to pay any more for housing in what is already an extremely high-priced market.

    "That's just going to drive the cost up and make California, once again, not affordable to live in," said California Assemblyman Brian Dahle.

    ④Severin Borenstein is an energy economist at the University of California, in Berkeley. He sent an email to the head of California's Energy Commission to urge the state to reconsider its decision.

    He expressed his belief that it is a mistake for California to approve such a policy instead of centering on efforts to develop large solar farms to produce renewable energy. He said these farms would cost much less to operate.

    "Every energy economist I know is shaking their head at this," he told the Wall Street Journal. "In many ways, this is setting the wrong example," he added.

    It is a psychological strategy that all parents will be familiar with: instead of scolding an misbehaving child, focus instead in rewarding them for good behaviour.

    Now the idea is well received outside the nursery, with implications for everything from recycling clothes to policing.

    Consumers end up with piles of unwanted clothes. Every year in the UK, 300,000 tonnes ends up in landfill — 235 million individual items.

    Now however, apps such as ReGain, Regive and Stuffstr are making it simpler — and more worthwhile — for people to return their unwanted clobber.

    The ReGain app can be used to find one of 20,000 drop-off points. In return, the diligent consumer earns rewards such as discount coupons for high street retailers. Stuffstr works in partnership with John Lewis to help people get cash in return for unwanted items from the chain.

    “Possibly the one prediction that we economists get right is that if you incentivise (激励) a behaviour, you will get more of it,” says Dr Matthew Levy, a lecturer in economics at the London School of Economics.

    He cites research, including his own, showing that financial incentives encouraging regular exercise, stopping smoking and losing weight effectively promote healthy behaviours and that there is no backlash when the incentives are removed.“If anything, the incentives can be used to jump-start a healthy habit that keeps going,”he says.

    In the four months after its launch, the ReGain scheme received almost 17,000 parcels containing 47 tonnes of used clothes and shoes, of which 95% could potentially be reused, according to its founder Jack Ostrowski.

    “We need to find a way to influence behaviour, and discount coupons help,” he says. The platform is also working with brands and retailers to find ways to divert used clothes from landfills and into the production of new clothes, he adds.

    Other reward schemes have had success in encouraging behavioural change.

    When police in Canada issued “positive tickets”— coupons for free food or movie tickets — to reward good behaviour among young people, they reported an almost 50% drop in youth-related service calls.

    “My officers would say' In the old days we'd drive up in the police car and the kids would run away from us, now they run to us'.”

    In a similar venture, Hull city council have announced plans to launch a digital reward token — the HullCoin — that can be earned by volunteering and spent at local retailers.

    Elsewhere, a study on the recruitment of health workers in Zambia found that highlighting economic incentives during the recruitment process caused future employees to be more motivated and task-focused.

    “Obviously different groups are motivated by different factors,” says Ostrowski. “For some, the feel good factor is enough, and for others, that reward stimulus is required.”