新的一期来了~~~ 撒花挂猴头庆祝 
大米姐姐走了，现在由我来接班，以后每周一跟大家不见不散
今天第一次发帖，一不小心就发晚了 该打该打~~~ 睡觉了的孩纸就当做第二天的晨读吧
大家多多指教，文章不喜欢、太难或者太简单就拿猴头 砸我吧~~~
我保证一定不会拿猴头砸回去
好了，进入正题上作业！ Time1是一篇文章，Time2,3是一篇，Time4，Time5单独为一篇
越障的话会有点长，分为两部分了，rest部分大家不捉急的话就看看吧~~ 其实也就600多字啊，捉急也要看！！好讨厌~~~ 人家第一天发贴子，不要不看完嘛~~~ [自行呕吐去~~]
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刚一发贴，发现明明每段之间专门空行了啊，肿么没有了~~ 而且格式怎么看起来那么丑！
格式强迫症犯了~~~我要研究一下！！！
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各种调之后终于可以见人了，大家将就一下下啦 下次会更好一些的！
Part I:[Speed] 速度
[Title] Cheetah-Cub: A Robot That Runs Like a Cat
[ Time 1 ]
Even though it doesn't have a head, you can still tell what kind of animal it is: the robot is definitely modeled upon a cat. Developed by EPFL's Biorobotics Laboratory (Biorob), the "cheetah-cub robot," a small-size quadruped prototype robot, is described in an article appearing today in the International Journal of Robotics Research. The purpose of the platform is to encourage research in biomechanics; its particularity is the design of its legs, which make it very fast and stable. Robots developed from this concept could eventually be used in search and rescue missions or for exploration.
This robot is the fastest in its category, namely in normalized speed for small quadruped robots under 30Kg. During tests, it demonstrated its ability to run nearly seven times its body length in one second. Although not as agile as a real cat, it still has excellent auto-stabilization characteristics when running at full speed or over a course that included disturbances such as small steps. In addition, the robot is extremely light, compact, and robust and can be easily assembled from materials that are inexpensive and readily available.
Faithful reproduction The machine's strengths all reside in the design of its legs. The researchers developed a new model with this robot, one that is based on the meticulous observation and faithful reproduction of the feline leg. The number of segments -- three on each leg -- and their proportions are the same as they are on a cat. Springs are used to reproduce tendons, and actuators -- small motors that convert energy into movement -- are used to replace the muscles. "This morphology gives the robot the mechanical properties from which cats benefit, that's to say a marked running ability and elasticity in the right spots, to ensure stability," explains Alexander Sprowitz, a Biorob scientist. "The robot is thus naturally more autonomous."
Sized for a search According to Biorob director Auke Ijspeert, this invention is the logical follow-up of research the lab has done into locomotion that included a salamander robot and a lamprey robot. "It's still in the experimental stages, but the long-term goal of the cheetah-cub robot is to be able to develop fast, agile, ground-hugging machines for use in exploration, for example for search and rescue in natural disaster situations. Studying and using the principles of the animal kingdom to develop new solutions for use in robots is the essence of our research." (401) http://www.sciencedaily.com/releases/2013/06/130617104608.htm
[Title]You Probably Agreed to NSA Snooping When You Accepted That Website’s Terms of Service Maybe we shouldn't be so shocked about PRISM, considering we grant companies like Facebook, Google and Apple incredible leverage to hand over our data to government agencies the moment we accept their terms of service agreements.
[ Time 2 ]
Everyone from Mark Zuckerberg down to the verage Facebook user has expressed surprised outrage at the existence of PRISM, a top-secret government program that the National Security Agency uses to access user data from at least nine major Internet companies in order to target foreign threats. But maybe we all shouldn’t be shocked at all, considering we grant companies like Facebook, Google and Apple incredible leverage to hand over our data to government agencies the moment we accept their privacy policies and terms of service agreements.
Tucked away in those long paragraphs of legalese on pretty much every major Internet website (including Time.com) is a clause about how a business will handle your private data when the feds come knocking. In general, these companies grant themselves wide latitude. Yahoo says it might hand out your data to investigate or prevent “situations involving potential threats to the physical safety of any person.” Facebook will respond to a court order, search warrant or other legal request “if we have a good faith belief that the law requires us to do so.” Apple provides user data to government agencies if “for purposes of national security, law enforcement, or other issues of public importance, disclosure is necessary or appropriate.”
It’s unclear whether even this kind of vague legal verbiage opens the door for a program as sweeping as PRISM has been reported to be. The exact nature of the data collection program is still unclear. Initial reports in The Washington Post and The Guardian painted a picture of a Big Brother-esque surveillance apparatus with unfettered access to massive amounts of data. The Director of National Intelligence responded by saying that all data acquired through the program, which targets only terrorist suspects who are not in the U.S., was lawfully obtained but through secret court orders made possible under the Foreign Intelligence Surveillance Act. A New York Times report last week fell somewhere in the middle, describing a “locked mailbox” for the NSA on tech companies’ servers where the government could routinely ask for the data it sought in its investigations. All the companies steadfastly deny any involvement in the program and say the government doesn’t have direct access to their servers. (367)
[ Time 3 ] Whatever the case, the now-acknowledged program takes data collection to a scope beyond what many users likely expected and possibly beyond what some companies’ terms of service allow. There’s a fine distinction between providing government officials private data when compelled to by a legal document like a court order and helping them to circumvent traditional legal channels. “If they say [they] only ever give up your data when compelled to do so by the government, but then it turns out they actually turn over your data routinely whenever the government says hello, then there might be a claim you could bring under the [Federal Trade Commission] Act,” says Andy Sellars, a staff attorney for the Digital Media Law Project based at Harvard University.
Such a contradiction could qualify as a deceptive trade practice under FTC rules. Companies have gotten in trouble for violating their own privacy policies before. In 2011, Google was forced to revamp its privacy policy and face regular independent privacy audits for 20 years because of “deceptive tactics” used in the rollout of failed social network Google Buzz. The company was hit with a $22.5 million penalty last year for misrepresenting privacy assurances to users of the Safari Internet browser. Microsoft and Facebook have also run afoul of the FTC for making false promises in their privacy policies. Still, the FTC has never levied a punishment that truly impacted a tech giant’s bottom line—that $22.5 million Google fine, the largest ever obtained by the FTC, is equivalent to the revenue the company generates in about four hours.
Individual consumers might also take aim at the PRISM companies, but their chances of success are slim. In 2006 when similar revelations about widespread government surveillance of telecommunications data came to light, Verizon was sued for $50 billion in a class-action lawsuit. But in 2008 Congress granted retroactive immunity to the telecom companies that were involved in surveillance programs, freeing them from legal culpability. Similar measures could be taken to protect Internet companies so that details of the PRISM program aren’t brought to light in a public court. According to the original Washington Post story, in fact, these companies already have immunity. (363)
[ The rest ] Of course, all of this only applies to the U.S. legal system. Companies like Google and Facebook have huge international customer bases, and PRISM is targeted squarely at non-Americans. In the European Union, where laws regarding the use of people’s personal data are more stringent than in the U.S., experts say that these Internet companies could face lawsuits.
Even if they do avoid legal trouble, tech companies–whose entire business models hinge on convincing users that their data is safe and secure–have every reason to want the PRISM story to go away as fast as possible. Google is now asking the White House for permission to publish information about the number of secret national security data requests it receives in its annual transparency report about government demands for user information. Facebook, which has never published a transparency report, is suddenly excited by the idea and also wants to include information on national security data requests. Microsoft and Twitter are on board too. (163) http://business.time.com/2013/06/14/you-probably-agreed-to-nsa-snooping-when-you-accepted-that-websites-terms-of-service/?iid=biz-main-lead
[Title]The dangers of insularity：
Islands may amplify the biggest waves, not break them
[ Time 4 ]
Surfers shun beaches shielded by islands off the coast. That, as generations of swarthy, golden-haired hulks will tell you, is because such islands create a natural breakwater. This dampens waves and makes for a boringly calm surf best left to sunbathers. The surfers’ reasoning is sound for the short-wave, wind-generated swells that they ride. But Themistoklis Stefanakis, of the Ecole Normale Supérieure in Cachan, France, warns it may not be true for the longer wavelengths of tsunamis. As he and his colleagues show in a paper posted on arXiv, an online repository, littoral islands may actually exacerbate, rather than diminish, the effects of these waves.
Anecdotal evidence for this counterintuitive assertion comes from (mercifully rare) episodes where the same tsunami has battered different types of coastal topography. In 2010, for instance, when one hit the Mentawai islands in Indonesia, areas of coastline directly behind islets bore the brunt of the damage, according to Costas Synolakis, a tsunami expert at the University of Southern California who is one of the study’s co-authors. Dr Synolakis, Mr Stefanakis and their colleagues decided to try to put numbers on their hunch. Rather than valiantly staking out seafront locales, though, they tested the idea with a computer model.
This is harder than it sounds. Simulating the way waves behave as they make landfall means taking account of, literally, oceans of data. To simplify the problem, the researchers looked at what happens when a computerised wave encounters a cone-shaped island on a smoothly sloping seabed in front of a straight cyber-coastline with a beach that continues to rise smoothly as it progresses inland. These approximations allow a computer to cope with the problem, yet are sufficiently similar to many real places for the conclusions drawn from them to, as it were, hold water.
The team made their virtual islet jut out of the ocean to an altitude of 100 metres, a typical height above sea level for such outcrops. They then looked at 200 combinations of gradients for the sides of the island, the seabed and the beach; the distance between the island and the beach; and the wavelength of the encroaching tsunami. In none of these did an island offer any succour to the coastline behind it. Instead, it acted as a lens, focusing the wave’s destructive power and amplifying its size by between 5% and 70%.
The upshot is that, far from shielding a coastline, offshore islands can make things worse—information that should be incorporated into tsunami evacuation plans. For if a big wave is coming, running from it is not enough. You also have to know how far to run before it is safe to stop. (444) http://www.economist.com/news/science-and-technology/21579439-islands-may-amplify-biggest-waves-not-break-them-dangers-insularity
[Title] Confessional Tweeting May Help Dieters Participants in a media-assisted weight-loss program had some success, and those who tweeted about their efforts lost a bit more. Karen Hopkin reports
[ Time 5 ]
Social media—it can help you keep up with friends, stay on top of the news, and maybe even fit into your skinny jeans. Because a study shows that using Twitter can help people lose weight. The results appear in the journal Translational Behavioral Medicine. [Gabrielle Turner-McGrievy and Deborah Tate, Weight loss social support in 140 characters or less: use of an online social network in a remotely delivered weight loss intervention]
Now, before you go thinking you can just Tweet yourself to a size 2, the volunteers in the study were taking part in a media-assisted weight loss program. For six months, 96 overweight participants tuned in to weekly podcasts about nutrition and exercise. In addition, half of them made use of mobile apps to track calories and physical activity, and to keep other folks in the study apprised of their progress.
On the whole, participants reduced their body weight by about 3 percent. But those who used Twitter lost even more: another half a percent for every 10 times they Tweeted.
Some Tweets offered emotional support, but many were simply informative. Like, “Avoided the pastries at this morning’s meeting. But I did have a skim mocha without whipped cream.”
Such confessional Tweeting may help dieters stay honest. Or at least keep their fingers occupied and out of the cookie jar （222） http://www.scientificamerican.com/podcast/episode.cfm?id=confessional-tweeting-may-help-diet-13-06-06
Part II：[ Obstacle ] 越障
[Title]Red dreams Mars has always been Shangri-La for space buffs. Two new private missions show that its lure is as strong as ever Jun 1st 2013 |From the print edition
[ Time 6 ]
ON JULY 20th 1969, when Neil Armstrong and Buzz Aldrin set foot on the Moon, it capped half a century of extraordinary progress in aviation. In the six and a half decades since the Wright brothers’Flyer had staggered into the air near Kitty Hawk, North Carolina, aeroplanes had shrunk the world, revolutionised warfare and created the modern travel industry. Technical records for altitude, speed and endurance had fallen helter-skelter.
For that reason, many of those watching the two astronauts on their black-and-white televisions could have been forgiven for thinking that going to the Moon was simply the first step in a human expansion into the solar system. Indeed, that had long been the dream of the space buffs who made the Moon missions possible. Wernher von Braun, the genius who designed the Saturn V Moon rockets—and who had been planning Mars expeditions since the publication, in 1948, of his book “Das Marsprojekt”—pitched a crewed Mars mission to then-President Richard Nixon soon after Armstrong and Dr Aldrin landed.
But it was not to be. The Apollo Moon programme was shut down early, and the world’s astronauts have spent the past 41 years pootling around in low-Earth orbit. Now, though, spurred by the rise of the buccaneering, private-sector “New Space” industry, which is offering access to the cosmos at prices far lower than government-backed rockets can manage, the old dream is enjoying a resurgence. Elon Musk, whose rocket firm SpaceX already flies cargo to the International Space Station (ISS), makes no secret of his Martian ambitions. Two privately run organisations in particular—Inspiration Mars, brainchild of Dennis Tito, an American tycoon who became the world’s first space tourist in 2001, and Mars One, run by Bas Lansdorp, a Dutch entrepreneur—have announced plans to send people to Mars without relying on the resources of a state.
Mr Lansdorp admits that, on hearing about his plans, people’s first response is that he must be crazy. But both he and Mr Tito (who started his career as an engineer at the Jet Propulsion Laboratory, JPL, in Pasadena, which runs NASA’s unmanned Mars missions) insist they are serious. Technical studies have been done, astronaut applications are being processed and deals are being signed with the firms that will build the spacecraft.
Both men are motivated by frustration with government efforts, which have gone around in circles—and not orbital ones—for decades. It is the stated policy of Barack Obama’s government to send a crewed mission to Mars in the 2030s. But given the recent history of NASA as a political football (the George Bushes senior and junior both proposed similar missions that went nowhere), and given looming cuts to its budget, few think such a mission will actually happen. As Mr Tito put it when he announced Inspiration Mars: “the way we’re going, we’ll never get started.”
Can-do talk aside, there are good reasons for scepticism. Sending people to Mars will be extremely difficult; far harder than sending them to the Moon. For one thing, Mars is much farther away. The Apollo missions took three days to get there, but flight times to Mars are measured in months. That would require an utterly reliable spacecraft. The vast distance imposes a communication delay, too. Whereas the Apollo astronauts could talk to their ground-based controllers more or less in real time, Martian astronauts would face delays of up to 40 minutes between asking a question and getting an answer.
And spending months in deep space would expose a crew to a chunky dose of radiation. Information from the Curiosity rover’s flight to Mars, just published in Science, suggests a crew could expect a radiation dose close to the maximum lifetime limit for NASA’s astronauts. If the sun were to have one of its regular temper tantrums, known as coronal mass ejections, which produce huge bursts of ionising radiation, that limit might be far exceeded.
When the stars are right Both missions hope to use SpaceX’s Falcon Heavy, a planned upgrade of its existing Falcon rocket. But even with access to cheap rockets, flying to Mars without the financial firepower of a government requires clever, and drastic, cost-cutting. In Mr Tito’s case, this means that although his astronauts will fly within about 140km (90 miles) of the Martian surface, they will not actually land. His mission calls for a two-person craft—possibly a variant of SpaceX’s Dragon capsule, which is already used to ferry cargo to the ISS—to be sent on a “free return” trajectory to Mars. By clever design of its orbit, the craft can be sent to Mars with a single burn of its rocket engine. From thereon in, gravity takes over. The craft will swing around Mars and emerge on a trajectory precisely calculated to have it re-enter Earth’s atmosphere several months later, with only minimal course corrections needed along the way. Orbital mechanics is one of Mr Tito’s specialities. Before he left JPL to become an investment manager, he designed orbits for Mars probes.
Removing the requirement to land simplifies the task enormously. No complex manoeuvring into a Mars orbit is necessary. No landing craft is needed, nor any survival gear for use on the Martian surface. That saves fuel and, more importantly, launch mass (the overriding concern for any space mission). Mr Tito’s team hopes to wring further savings by launching in 2018, in order to take advantage of a rare set of celestial circumstances that allow a gravity-powered trip to Mars and back in 501 days, instead of the two years that would normally be required. That keeps food and water requirements low.
“There is nothing technically infeasible about Tito’s plans,” says Robert Zubrin, who runs the Mars Society, which lobbies for human trips to Mars, and who has spent decades thinking about exactly how such missions might be executed. Mr Tito’s team has plenty of technical nous, as well as a deal with NASA to develop technology. It plans to recycle as much kit as possible from the ISS, whose life-support systems have proved themselves reliable for more than a decade.
Of course, saying that something is technically feasible does not mean that it is easy. Mr Tito’s mission will push the bounds of space flight. A year and a half is long time to spend cooped up in a craft the size of a motor-home, but Dr Zubrin points out that similar feats have already been achieved. Valeri Polyakov, a Russian cosmonaut, spent 438 days in space in 1994 and 1995. Four other Russian and Soviet missions have been over 300 days long. Mr Tito hopes to keep personal conflict to a minimum by sending a married couple—ideally one past child-bearing age, to eliminate the risks of accidental pregnancy and radiation-induced infertility.
The return to Earth could also be difficult. Inspiration Mars’s spacecraft will slam into Earth’s atmosphere at 14.2km a second, significantly above the 11km/s speed of Apollo. No existing heat shield could deal with such re-entry speed. But Taber MacCallum, the head of Paragon Space Development, an engineering firm, who is one of Mr Tito’s chief collaborators, says modern materials should be up to the task of making a new one.
Assuming the engineering questions can be solved, Mr Tito’s chief problems will then be time and money. His mission faces a hard deadline. If it is not ready by January 2018, the intricacies of orbital mechanics mean there will not be another chance of such a short trip until 2031. And even a stripped-down, Spartan mission that uses as much existing technology as possible and makes no attempt to land will be expensive. Inspiration Mars gives no official cost estimates, but Jeff Foust, the editor of theSpace Review, an industry newsletter, thinks it could be done for “very roughly, around a billion dollars”, a sum that Mr Tito may try to raise through a personal donation, the sale of media rights, sponsorship deals and charitable appeals to his fellow tycoons.
It is a big task, and a dangerous one, but it is not beyond what technology allows. Dr Foust, for instance, gives Mr Tito about a one chance in three of succeeding. Even if everything does go according to plan, though, cynics might question the value of a billion-dollar, one-and-a-half year trip that comes within spitting distance of Mars but does not land. Dr MacCallum points out that even a fly-by would generate a great deal of publicity. “It would be a [Charles] Lindbergh” mission, says Dr Zubrin. “The point would be to prove it can be done.” (Though, since it would involve a pair of people making a hazardous journey for the first time, rather than a copy-cat, albeit solo, trip eight years later, a better comparison would be with Alcock and Brown, two British pilots who flew the Atlantic in 1919.) (1473)
[ The rest ]
Marooned on Mars Mr Tito intends to simplify things by not landing. The Mars One project intends to simplify them by not taking off. Its four crew members, if they arrive intact, will live out the rest of their lives on Mars. They will build a settlement from their spacecraft and from inflatable living areas covered with regolith (the crushed rock that passes for soil on the planet). Nor will this be a one-off. Every two years the Martians will be joined by four more refugees from Earth, with the eventual aim of building up a full-fledged colony. As far as possible, they will produce food, water and materials in situ, though regular cargo launches from Earth will supplement these.
If Inspiration Mars is working to a brisk schedule, then Mars One’s plans seem positively frantic. The organisers aim to build a replica habitat, to be used for training, on Earth this year. An uncrewed supply mission will be launched in 2016, so that the first astronauts (who would arrive in 2023) will find useful kit ready and waiting. Robot rovers will be sent ahead as scouts to look for a suitable location for the homestead. The whole thing will be broadcast, so television rights—along with sponsorship deals, donations and possibly technology licensing—will pay the enormous cost ($6 billion for the first manned flight alone). At least, that is the theory.
It all sounds like a science-fiction writer’s fever dream. But the basic idea is nothing new. Mars advocates have been pondering one-way trips since the early 1990s, because this drastically simplifies the mission. Dr Aldrin, a keen advocate of manned space flight and one of the few people with experience of flying in deep space, is convinced that it is the way to go. And although most people would balk at the idea of spending several risky months traversing a vacuum so that they can live out their days in a freezing, airless desert millions of miles from home, the lure of Mars is strong for some. Mars One says that, since it opened the application process in April, it has had almost 80,000 people express an interest in becoming one of its astronauts. (In keeping with the media-friendly theme of its operation, Mars One allows anyone to apply to become an astronaut, and plans to televise the astronaut-selection process.)
Mr Lansdorp insists that his plans can work. “Whenever I talk to engineers, they say the engineering is doable, but what about the finance?” he says. “Then when I talk to the finance guys, they say the finance is fine, but are you sure you can make the engineering work?” Few others, though, are quite so confident. Dr Foust is polite. “Any one of the things they’re describing—flying people to Mars, landing on Mars, living on Mars—is very difficult,” he says. “Doing all of those at once is even more so.” Others, privately, are scathing: “It’s a real shame that something like this is getting so much publicity,” says one such anonymous expert. “It gives the whole private space industry a bad name.”
It is entirely possible—likely, even—that neither of these missions will happen. Mr Tito has the better chance, but there are many more ways for him to fail than to succeed. Mr Lansdorp’s plans look too ambitious to be credible. And NASA’s recent history suggests that its aspirations, too, will be blown off course by a future president. But all this will not deter true believers, who have been discussing how to run a Mars trip for decades. With the cost of space flight lower than ever, it seems unlikely that the dream will die. So even if the present crop of missions come to nothing, they will not be the last. (631) http://www.economist.com/news/science-and-technology/21578637-mars-has-always-been-shangri-la-space-buffs-two-new-private-missions-show
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