When it comes to the Internet, people talk about the password most. Actually, it's been under fire for a long time. Research has shown that passwords are not a very good way to protect sensitive information.

    People would use some random characters, numbers and symbols. Furthermore, a unique password would be used for every site or application the user uses. Unfortunately, the longer and more complex passwords become, the more people are likely to forger them. Therefore, they use the same password for every service or application. These are all big no-noes and essentially defeat the purpose of a password.

    Google is trying to kill off passwords on Android devices by introducing the Trust API, which does what simple passwords cannot and gives developers a framework for securing their application using a number of security systems and metrics(衡量标准)on the device. A Trust Score will be generated based on a number of metrics including your device location, face scanning, fingerprints, and the things like your typing speed or the way you speak. Taken one at a time, these metrics are not secure. But taken together, these metrics will help recognize the real “you”.

    The good news is that Google has already been testing this on real world data. Google has proven the Trust API works. Next Google will run tests will some banks to see if the Trust API meets their needs before rolling out the system on Android phones later. It may take another year for apps and popular sites to start using the Trust API.

    This is a pretty exciting change. Passwords have been around for a lone time. Although the security of systems has been improved, the usability of systems hasn't been proved much. Google appears to have the best of them. Maybe that never-ending conflict between security and convenience will be able to take a break once the Trust system comes out.

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    World Expo 2010 will be held in Shanghai. It will last from May 1st to October 31st, 2010. The Expo site covers a total area of 5.28 km². It spans(横跨) both sides of the Huangpu River, with 3.93 km² in Pudong and 1.35 km² in Puxi. There are five functional zones marked A, B, C, D and E. Each of them has different functions.

    Zone A will host the national pavilions(国家馆) of Asian countries except southeast Asian ones.

    Zone B will be home to the China Pavilion(中国馆) and Oceania (大洋洲的) countries, Pavilions for International Organizations, Theme Pavilions(主题馆), Expo Centre, and Performance Centre etc.

    Zone C will host the national pavilions of European, American and African countries. A large public amusement park will be built at the entrance of this zone.

    Zone D is home to Corporate Pavilions(企业馆), the land is one of the original places of modern China's national industry. So some of the old industrial buildings will be kept and renovated(修复) into Expo pavilions.

    Zone E will host stand-alone(独立的) Corporate Pavilions, Urban Civilization Pavilion (城市文明馆), and Urban Best Practices Area.

The idea of being able to walk on water has long interested humans greatly. Sadly, biological facts prevent us ever accomplishing such a thing without artificial aid—we simply weigh too much, and all our mass pushes down through our relatively small feet, resulting in a lot of pressure that makes us sink.

    However, several types of animals can walk on water. One of the most interesting is the common basilisk Basilicus basilicus, a lizard (蜥蜴)native to Central and South America. It can run across water for a distance of several meters, avoiding getting wet by rapidly hitting the water's surface with its feet. The lizard will take as many as 20 steps per second to keep moving forward. For humans to do this, we，d need huge feet that we could bring up to our ears in order to create adequate w hitting.

    But fortunately there is an alternative : cornflour. By adding enough of this common thickening agent to water (and it does take a lot), you can create a “non-Newtonian” liquid that doesn't behave like normal water. Now, if the surface of the water is hit hard enough, particles(粒子）in the water group together for a moment to make the surface hard. Move quickly enough and put enough force into each step, and you really can walk across the surface of an adequately thick Liquid of cornflour.

    Fun though all this may sound, it's still rather messy and better read about in theory than carried out in practice. If you must do it, then keep the water wings handy in case you start to sink--and take a shower afterward!

    In most parts of the world, many students help their schools make less pollution. They join “environment clubs”. In an environment club, people work together to make our environment clean.

    Here are some things students often do.

    No-garbage lunches. How much do you throw away after lunch? Environment clubs ask students to bring their lunches in bags that can be used again. Every week they will choose the classes that make the least garbage and report them to the whole school.

    No-car day. On a no-car day, nobody comes to school in a car. Not the students and not the teachers! Cars give pollution to our air, so remember: walk, jump, bike and run. Use your legs! It's lots of fun.

    Turn off the water! Did you know that some toilets can waste twenty to forty cubic (立方) meters of water an hour? In a year, it would fill a small river! In environment clubs, students mend those broken toilets. We love our environment. Let's work together to make it clean.

    If you're new to San Francisco, paying the city a visit, or simply looking for a new playground for you and your dog, here are four of the finest dog parks in San Francisco.

    Corona Heights Dog Park

    Often visited by residents from all over the city because of its nearness to the Randall Museum, Corona Heights Dog Park offers pets and owners breathtaking views, after a steep hillside climb, and a fenced dog area that allows dogs to let loose without a leash （狗链）. Owners will also enjoy the playground, tennis courts and basketball courts.

    Dolores Dog Park

    The grounds of Dolores Park once served as camps for those who were left homeless by the 1906 earthquake, but now often visited by crowds of Mission District people. Four-legged friends can also wander about carefree off-leash while making friends with other members of the doggie community.

    Pine Lake Dog Park

    Noteworthy for its place as a rest stop for hundreds of species of birds to fly to and from warmer climates, Pine Lake Park is also prized by city dogs and their owners for their nice hiking paths, picturesque lake suited for swimming, and an off-leash area on the park's west end that lets dogs run free.

    Buena Vista Dog Park

    At 146 years young, Buena Vista Park is San Francisco's oldest park. Dogs and owners with plus energy will love burning it on this park's steep paths and winding staircases. Dog owners should have good control over their dogs, as it's quite easy for dogs to get separated when going through Buena Vista's many twists and turns.

    Play time is in short supply for young children these days and the lifelong consequences for developing children can be more serious than many people realize.

    An article in the most recent issue of the American Journal of Play details not only how much children's play time has declined, but how this lack of play affects emotional development, leading to the rise of anxiety, depression, and problems of attention and self control. “Since about 1955, children's free play has been continually declining, at least partly because adults have applied ever-increasing control over children's activities.” says the author Peter Gray, Ph. D, Professor of Psychology at Boston College.

    We can describe the unstructured freely-chosen play as a testing ground for life. It provides critical life experiences without which young children cannot develop into confident and competent adults. So kids need more of it, not less. Because play is how young children learn important social and emotional skills such as sharing, cooperating, communicating, and empathizing. It helps them develop fit bodies, strong minds, and brave hearts, so they can take on new challenges and risky situations.

    Gray's article is meant to serve as a wake-up call regarding the effects of lost play. We must know that lack of childhood free play time is a huge loss that must be paid attention to for the sake of our children and society. But parents who keep a lookout over and disturb their children's play are a big part of the problem. It is hard to find groups of children outdoors at all, and, if you do find them, they are likely to be wearing school uniforms and following the directions of coaches while their parents dutifully watch and cheer.

    Actually, when children are in charge of their own play, it provides a foundation for their future mental health as older children and adults. Play gives children a chance to find and develop a connection to their own self-identified and self-guided interest. It is through play that children first learn to make decisions, solve problems, improve self-control, and follow rules. Play helps children make friends and learn to get along with each other as equals. Most importantly, play is a source of happiness.

When parents realize the major role that free play can take in the development of emotionally healthy children and adults, they may wish to reassess the priorities ruling their children's lives. The needs for childcare, academic and athletic success and children's safety is important. But perhaps parents can begin to identify small changes——such as openings in the schedule, backing off from quite so many supervised (有监督的) activities, and possibly slightly less keeping watch on the playground that would start the slow returning to the direction of free, imaginative-directed play.