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Hydroplaning happens when a vehicle moves too quickly along a wet road. A layer of water accumulates under the tires; they lift up and lose traction; the driver loses control.当车辆在潮湿的路面上开得太快时会出现打滑现象。轮胎下聚积的一层水会抬高轮胎,失去牵引力,驾驶员会失去对车辆的控制。Now, what does NASA have to do with hydroplaning?美国国家航空航天局与打滑现象有什么关系呢?Heres an historical look at the science story.我们来看下科学的历史。Hydroplaning is a relatively new phenomenon for humans, given that the combination of high speed and smooth pavement thats necessary has only fairly recently become possible.打滑现象对人们来说是相对较新的现象,因为高速和光滑的人行道也是最近相对才有的。In fact, it wasnt until 1957 that a tire tmill study first experimentally demonstrated hydroplaning “in action.”事实上,直到1957年一台带轮胎的踏车最先通过试验演示了打滑现象的存在。That study was motivated by airplanes.那项研究是由飞机引发的灵感。Hydroplaning had been causing a lot of problems for pilots landing on wet runways.飞行员降落在潮湿跑道上,打滑现象已经给他们造成了大量的问题。Heres where NASA comes in. NASA scientists wanted to figure out what hydroplaning was all about.这也是NASA介入的原因。NASA科学家试图弄明白打滑现象究竟是怎么回事。So, they collected a lot of data, and produced a mathematical formula to illustrate how quickly a vehicle could travel on a wet surface before entering hydroplane mode.因此,他们收集了很多数据,并且得出一个数学公式来说明车辆在潮湿的路面以多快的速度行驶就会打滑。They published the equation in 1963, along with information about the effects of water depth, paving technique, tire t, and vehicle weight on hydroplaning risk.1963年,科学家们公布了这个数学公式,同时告诉大家水的深度、人行道的铺设技术,轮胎面以及车的重量对打滑的影响。This publication offered several important safety tips.这次信息的公开提供了几个重要的安全提示。For example, use well-ted, fully inflated tires; and, dont slam on the brakes if you skid on wet pavement.例如,使用较好的轮胎面,完全充气的轮胎,如果你在潮湿的地面上刹车时,不要用力踩刹车。These suggestions may sound commonplace, and we now also know that vehicles with anti lock brakes require slightly different hydroplane handling than those without.这些建议似乎是老生常谈,我们现在也知道带防锁死刹车装置的车辆处理打滑现象时与没有该刹车的车辆稍有不同。However, we can thank those NASA scientists from fifty years ago for getting the word out, and helping to keep all drivers-on runways and roads-safer on rainy days.但无论如何,我们都要感激50年前NASA科学家们告诉我们打滑现象,使所有跑道和道路上的驾驶员在雨天能更安全行驶。201401/272534Science and technology科学技术Pilotless aircraft无人机Giving drones a thumbs up向无人机打手势How to integrate the control of piloted and pilotless aircraft如何让指挥有人机的方法适用于无人机DECK officers on American aircraft carriers use hand gestures to guide planes around their vessels.在美国的航空母舰上,甲板指挥员会用手势指挥母舰附近的飞机。These signals are fast, efficient and perfect for a noisy environment.这种信号快速、高效,而且十分适用于嘈杂的环境。Unfortunately, they work only with people.但遗憾的是,只有人才能读懂这些手势。They are utterly lost on robotic drones—and even if a drone is under the control of a remote pilot deep in the bowels of the ship,在无人机上,这一套完全失效;而即便有飞行员在船舱深处远程操控这架飞机,that pilot often has difficulty ing them.他往往也很难识别那些手势。Since drones are becoming more and more important in modern warfare, this is a nuisance.这是个麻烦,因为无人机在现代战争里变得越来越重要了。Life would be easier for all if drones were smart enough to respond directly to a deck officers gesticulations.若无人机的智能达到了足以直接响应甲板指挥员手势的程度,那一切都会好很多。Making them that smart is the goal of Yale Song, a computer scientist at the Massachusetts Institute of Technology.让无人机具备这样的智能是麻省理工学院计算机科学家Yale Song的目标。He is not there yet but,这个目标虽尚未达成,as he reports in ACM Transactions on Interactive Intelligent Systems,不过正如他在《美国计算机学会交互式智能系统学报》所报告的,he and his colleagues David Demirdjian and Randall Davis have developed a promising prototype.他和他的同事David Demirdjian和Randall Davis已开发了一个很有前景的原型系统。To try teaching drones the language of hand signals Mr Song and his colleagues made a series of s in which various deck officers performed to camera a set of 24 commonly used gestures.为了让无人机读懂手语,Yale Song和他的同事制作了一系列视频,视频记录了多位甲板指挥员对着摄象机摆出的24个常用手势。They then fed these s into an algorithm of their own devising that was designed to analyse the position and movement of a human body, and told the algorithm what each gesture represented.然后他们用一个自己设计的算法来处理这些视频,并让算法知道每个手势的意义。The idea was that the algorithm would learn the association and, having seen the same gesture performed by different people,他们的设想是,该算法会记住每个手势所对应的意义,而在对不同人摆出的相同手势进行处理后能够概括出手势本身的意义,would be able to generalise what was going on and thus recognise gestures performed by strangers.从而识别任何人摆出的手势。Unfortunately, it did not quite work out like that.很遗憾,实际与预想的不太一样。In much the same way that spoken language is actually a continuous stream of sound,其实指挥飞行员所用的手语和人说的话差不多。so the language of gestures to pilots is also continuous, with one flowing seamlessly into the next.后者实际上是一串连续的声音,而手语同样也是连续的,因为两个动作之间是连贯的。And the algorithm could not cope with that.但该算法无法处理这种连续的信息。To overcome this difficulty Mr Song imposed gaps by chopping the s up into three-second blocks.为了解决这个问题,Yale Song以3秒为一段将视频截开,在各段之间插入时间间隔。That allowed the computer time for reflection.这样就给计算机留出了响应时间。Its accuracy was also increased by interpreting each block in light of those immediately before and after it,同时识别的准确率也有所提高。因为这样计算机就能根据前一段及后一段的视频来理解当前这一段,to see if the result was a coherent message of the sort a deck officer might actually wish to impart.看看结果是不是那种甲板指挥员可能真的想摆出的有特定意义的手势。The result is a system that gets it right three-quarters of the time.他们最终做出了一个正确率为75%的系统。Obviously that is not enough:显然,那样是不够的:you would not entrust the fate of a multi-million-dollar drone to such a system.你不会将一架价值数百万美元的无人机交给这样的系统。But it is a good start.但这是个好的开始。If Mr Song can push the accuracy up to that displayed by a human pilot, then the task of controlling activity on deck should become a lot easier.若Yale Song能将无人机识别手势的正确率提高至与真人飞行员相当,那么在甲板指挥无人机会容易得多。 /201307/247186Business商业报道The circus business马戏团商业Sunstroke日射热Cirque du Soleil may be struggling, but the cluster around it is thriving太阳马戏团或许正处于苦斗之中,但围绕其四周的星团正熠熠发光。No lions, no bearded ladies 没有狮子,没有胡子的女士IN THE deconsecrated church of Saint-Esprit, jugglers toss fluorescent orange clubs in front of the former altar, trapeze artists soar under the gaze of stone saints and wobbly unicyclists use two lines of repurposed pews as handrails.在蓬圣埃斯普里神圣的教堂里,杂耍艺人们在从前的祭坛前抛掷橙色荧光棒,高空表演者在石像圣人的凝视下飞来飞去,摇摆的骑独轮自行车表演者用两条赋予了新用途的教堂长凳作为扶手。Declared surplus to requirements after Quebeckers deserted Catholicism in droves, the church is now the ecole de Cirque de Quebec, through which 20,000 aspiring entertainers pass each year.在魁比克人成群结队地公然宣布放弃天主教后,教堂被余下来,通过每年录取20000多个有抱负的艺人,成为了现在的魁比克马戏团学校。The schools director, Yves Neveu, says only half-jokingly, Someone said the archbishop should be jealous because Im filling my church.学校的主任,伊夫?奈芙,半开玩笑地表示,有人说大主教应该嫉妒,因为我正填满我的教会。Nearby Montreal boasts an even bigger school for circus performers.而在不远的蒙特利尔,还有一间更大的杂技表演学校。Although only a handful of students go on to a career in the circus, the popularity of the programmes offered to would-be acrobats,尽管仅有少数学生会继续在马戏团的职业生涯,但为想要成为杂技演员的人提供了普及课程,local children and even tourists off cruise ships is the visible manifestation of the circus craze that has gripped Quebec.当地的孩子,甚至游轮中游客的狂热程度都明显表示马戏团的热潮已经席卷整个魁北克。At its heart is the privately owned Cirque du Soleil, started in 1984 by a troupe of stilt-walkers from nearby Baie-Saint-Paul.浪潮的核心正是由圣保罗湾附近的一个踩高跷戏班子1984年开创的太阳马戏团。It is now one of Canadas most important cultural exports, employing 5,000 people at eight permanent shows in Las Vegas and at 12 others that tour the world.现在,太阳马戏团是加拿大最重要的文化输出产业之一,员工达5000人,有八场在的固定演出和十二场世界巡演。In 2012 its turnover was about C1 billion—it does not reveal its profits.2012年其营业额约1000000000加元-其利润并未透露。In 2005 this newspaper asked whether Guy Laliberte, majority owner of the circus, could keep it flying.2005年杂志向马戏团创始人盖?拉利伯特问道,能否保持马戏团风光下去。That question was raised again early last year when the company laid off 400 employees, mainly at its head office in Montreal.去年年初,蒙特利尔公司总部裁员400人时,这个问题再次被提出。The company has blamed the strong Canadian dollar and the after-effects of the global recession, which hit sponsorship income.太阳剧团将此归咎于加币走强和全球经济衰退的后续效应,削弱了赞助收入。It has launched a cost-cutting drive but insists it is not in crisis虽然剧团开始削减成本,但坚称并未面临危机。.However, the company that reinvented the circus by eschewing traditional acts such as lion tamers and bearded ladies, and by targeting adults rather than children, is certainly finding it tougher going these days.然而,避开马戏团的狮子驯兽师、大胡子女士们等传统表演方式,将目标人群定位在成年人而非儿童,重新改造了的马戏团,现在的处境一定是艰难的。It enjoyed early and rapid success because it had created an uncontested blue ocean in which to swim, according to two management strategists from INSEAD business school in France.两位法国INSEAD商学院的战略管理专家表示,剧团能够享受到早期快速的成功,是因为其建立了一个没有竞争的蓝海。That ocean is now full of sharks, says Gilles Ste-Croix, one of the original stilt-walkers, who is now the companys artistic guide.现如今那片海满是鲨鱼。最初的高跷步行者之一,现公司年代艺术指导,吉尔斯圣克鲁瓦如是说。Competition comes not just from older circuses that have updated their acts, such as Ringling Bros. and Barnum amp; Bailey, but also from a trend in the arts to merge various disciplines, for instance by bringing acrobats into operas.剧团的竞争压力不仅来源于更新表演内容的旧有马戏团,如林林兄弟巴纳姆贝利马戏团,而且也来自于在多种学科融合的一个艺术趋势,比如让杂技走进歌剧。Smaller rivals have also emerged from the large shadow Cirque du Soleil casts in Quebec.小型竞争竞争者也在太阳马戏团投射在魁北克巨大的阴影下崛起。A troupe called Les 7 doigts de la main set a box-office record at the Broadway theatre where they performed a show called Pippin.剧团七指马戏团在百老汇剧院表演彼平正传,创造了票房纪录。Flip FabriQue, formed by a group of friends just two years ago, is now travelling the world.由一群朋友就在两年前创立的FabriQue也开始世界巡回。And Cirque Alfonse toured Europe, Asia and America in 2013 with a truly Canadian spectacle called Timber!, which features chainsaw-juggling lumberjacks.阿尔冯斯马戏团2013年带着真正的加拿大表演伐木乐园游历了欧洲、亚洲和美国,该剧充分展现电锯杂耍伐木工人的特点。These newer outfits are both a source of competition and collaboration for Cirque du Soleil, with performers moving back and forth.表演者来来去去,这些新的组织既是太阳马戏团的竞争者也是合作对象。It also collaborates with notable local talents, such as Robert LePage, a director, playwright and actor whose company Ex Machina is based in Quebec City.此外,马戏团与当地的知名人才合作,如罗伯特-勒帕热,一位公司总部位于魁北克市的导演,演员和剧作家。This has reinforced what has become a Quebec entertainment cluster.强化魁北克的产业。Mr Neveu, a Cirque du Soleil alumnus, thinks that rather than serving a spell with his former employer, many of the students at his school will go straight to work in one of the many smaller troupes, which he sees as a healthy trend.太阳马戏团的校友奈芙先生认为,学校的很多学生将直接在新的小团中工作而不是为其前雇主轮流演出,他也相信这是一个好的趋势。Even so, Cirque du Soleil remains the sun around which all the others are orbiting.即便如此,太阳马戏团仍是其他团体围绕旋转的太阳。 /201402/276622

Stressed parents压力下的父母Cancel that violin class取消小提琴补习班Helicopter moms and dads will not harm their kids if they relax a bit揠苗助长的父母们,放松点,对孩子没坏处。WELL-TO-DO parents fear two things: that their children will die in a freak accident, and that they will not get into Harvard. The first fear is wildly exaggerated. The second is not, but staying awake all night worrying about it will not help—and it will make you miserable.富裕家庭的父母害怕两件事情:一件是他们的孩子死于意外事故,另一件是,孩子进不了哈佛读书。第一件可能过分的夸张,第二件则绝对真实。但是担心得夜不能寐起不到任何帮助作用,只会让你觉得痛苦。Modern parents see risks that their own parents never considered. They put gates at the top of stairs, affix cushions to table corners and jam plastic guards into sockets to stop small fingers from getting electrocuted. Those guards are “potential choking hazards”, jests Lenore Skenazy, the author of “Free-Range Kids”. Ms Skenazy let her nine-year-old son ride the New York subway on his own. He was thrilled; but when she spoke about it on TV, a mob of worrywarts called her “Americas worst mom”.现在的父母看到了他们上一辈从未注意到过的危险。他们把大门安在楼梯顶上,给桌子安上桌角防撞贴,给插座插上保护盖以防止孩子的小手指触电。 《自由放养孩子》一书作者Lenore Skenazy开玩笑的说,这些防护装置有潜在的窒息危险。Skenazy让她九岁的孩子自己乘坐纽约的地铁。孩子因此非常激动,但当Skenazy在电视上讲到此事,一群杞人忧天人士则说她是“美国最糟糕的母亲”。Yet in fact American children are staggeringly safe. A kid under five in the 1950s was five times as likely to die than the same kid today. The chance of a child being kidnapped and murdered by a stranger is a minuscule one in 1.5m.然而,事实上美国的孩子们异常安全。在二十世纪五十年代,5岁以下孩子死亡率是现在的5倍。孩子被陌生人绑架、谋杀的可能性只有微不足道的150万分之一。What about academic success? Surely the possibility of getting into Harvard justifies any amount of driving junior from violin lesson to calculus tutor?那学术上取得成功又是怎么样的呢?进入哈佛的可能性当真明了有从小提琴到微积分都很厉害的孩子?Bryan Caplan, an economist at George Mason University, says it does not. In “Selfish Reasons To Have More Kids”, he points to evidence that genes matter far more than parenting. A Minnesota study found that identical twins grow up to be similarly clever regardless of whether they are raised in the same household or in separate ones. Studies in Texas and Colorado found that children adopted by high-IQ families were no smarter than those adopted by average families. A Dutch study found that if you are smarter than 80% of the population, you should expect your identical twin raised in another home to be smarter than 76% but your adopted sibling to be average. Other twin and adopted studies find that genes have a huge influence on academic and financial success, while parenting has only a modest effect.乔治梅森大学的经济学家Bryan Caplan说,事实并非如此。在《多要孩子的自私原因》一书中,他拿出据指出,基因的影响力远大于教养的影响力。明尼苏达州的一项研究表明,同卵双胞胎不论是否在同一家庭环境中成长,他们长大后的聪慧程度是相似的。德克萨斯州和科罗拉多州的研究发现,被高智商家庭收养的孩子并没有比普通家庭收养的孩子聪明。荷兰一项研究发现,如果你比80%的人聪明,那么你生的、在别的人家抚养起来的同卵双胞胎,将会比76%的人聪明,而你自己领养的孩子则是平均水平。其他关于双胞胎和领养的研究显示,基因对学术和经济上的成功有着巨大的影响,而教养只有轻微的作用。The crucial caveat is that adoptive parents have to pass stringent tests. So adoption studies typically compare nice middle-class homes with other nice middle-class homes; they tell you little about the effect of growing up in a poor or dysfunctional household.关键的警告是,养父母必须经过严格的测试。因此,领养研究通常在不错的中产家庭之间比较,并没有说明在贫穷或非正常家庭中成长会有什么影响。The moral, for Mr Caplan, is that middle-class parents should relax a bit, cancel a violin class or two and let their kids play outside. “If your parenting style passes the laugh test, your kids will be fine,” he writes. He adds that if parents fretted less about each child, they might find it less daunting to have three instead of two. And that might make them happier in the long run. No 60-year-old ever wished for fewer grandchildren.对Caplan来说,其意义就是中产家庭父母应当放松点,取消一两个小提琴班,让孩子在外面玩玩。他在书中写到:“如果你的养育形式通过了欢乐测试,你的孩子就会很棒。”他补充说,如果父母少焦躁的对待孩子,父母可能会发现三个孩子比两个孩子更好。这会使他们在长期内更加快了。60岁的人(代指老年人)都希望有更多的孙辈。Does over-parenting hurt children? Probably not; but it exhausts parents. Hence the cascade of books with titles like “All Joy And No Fun” and “Go The F**k To Sleep”. Kids notice when their parents are overdoing it. Ellen Galinsky, a researcher, asked 1,000 kids what they would most like to change about their parentsschedules. Few wanted more face time; the top wish was for mom and dad to be less tired and stressed.过度的教养伤害到孩子了吗?可能并没有。但是它让父母筋疲力尽。所以有一连串像《所有的快乐与不快乐》和《去他妈的睡觉》这样的书名。孩子会注意到父母们什么时候过头了。一名为Ellen Galinsky的研究员询问了1000名孩子,问他们最想改变其父母时间表上的哪些东西。很少有孩子想要跟父母见面的时间。最大的心愿是,让爸爸妈妈不再那么紧张劳累。 /201407/316287

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