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南平排卵监测什么医院好龙岩试管生儿子费用多少Science and Technolgy.科技。Visible-light communication.可见光通信。Tripping the light fantastic.与光共舞。A fast and cheap optical version of Wi-Fi is coming.一个高速而廉价的光学Wi-Fi即将问世。AMONG the many new gadgets unveiled at the recent Consumer Electronics Show in Las Vegas was a pair of smartphones able to exchange data using light.最近,在国际消费电子展上首次展出的电子产品中,有一对能利用光交换数据的智能手机。These phones, as yet only prototypes from Casio, a Japanese firm, transmit digital signals by varying the intensity of the light given off from their screens.目前,这两部不过是日本卡西欧公司的样机,它们能通过改变自身屏幕的光强来传传输数字信号。The flickering is so slight that it is imperceptible to the human eye, but the camera on another phone can detect it at a distance of up to ten metres.这样的闪光很微弱,人眼无法感知,但另一部手机的摄像头能够在十米的范围内检测得到。In an age of Wi-Fi and Bluetooth, flashing lights might seem like going back to sending messages with an Aldis lamp.在这个Wi-Fi和蓝牙横行的时代里,使用闪光可能有点像回到用奥尔迪斯手提信号灯发送信息的年代。In fact, they are the beginning of a fast and cheap wireless-communication system that some have labelled Li-Fi.事实上,它们正是有人称之为Li-Fi的高速、廉价的无线通讯系统的鼻祖。The data being exchanged by Casios phones were trifles: message balloons to be added to pictures on social-networking sites.两部卡西欧手机交换的数据量非常小:不过是添加在社交网站图片中的虚拟对话框。But the firm sees bigger applications, such as pointing a smartphone at an illuminated shop sign to information being transmitted by the light: opening times, for example, or the latest bargains.但卡西欧公司发现这项技术有更大的应用前景,比如将智能手机对准发光的商店招牌读取通过灯光传送的信息:如营业时间或最新优惠。Yet that is still only a flicker of what is possible.但是,这项技术可能有万千功能,以上不过是冰山一角。Last October a number of companies and industry groups formed the Li-Fi Consortium, to promote high-speed optical wireless systems.去年十月,多家公司及实业集团共同成立了Li-Fi联盟,以推广高速无线光学通信系统。The idea is that light can help with a looming capacity problem.他们的想法是可见光通信将有助于解决即将来临的数据传输瓶颈问题。As radio-based wireless becomes ubiquitous, more and more devices transmitting more and more data are able to connect to the internet, either through the mobile-phone network or through Wi-Fi.随着无线电通讯的普及,越来越多的数据传输量越来越大的设备能够通过移动网络或Wi-Fi与互联网连接。But there is only a limited amount of radio spectrum available.但可用于通信的无线电频段是有限的。Using light offers the possibility of breaking out of this conundrum by exploiting a completely different part of the electromagnetic spectrum, one that is aly ubiquitous because it is used for another purpose: illumination.运用一个完全不同的电磁波段——可见光,就有可能解决这个难题;这个波段其实早已相当常用,因为它有另一个作用:照明。Lighten the darkness.照亮黑暗。To turn a light into a Li-Fi router involves modulating its output, to carry a message, and linking it with a network cable to a modem that is connected to a telephone or cable-broadband service, just like a Wi-Fi router.要将一个可见光源变成能够携带信息的Li-Fi路由器,需要调制其光强以及用网线将其与一个调制解调器(与电话或宽带网线相连)连接,一如Wi-Fi路由器。Incandescent light bulbs and fluorescent tubes are not really suitable for modulation, but they are yesterdays lighting technology.白炽灯和日光灯的光其实并不适合调制,不过它们已是旧式的照明技术了。Tomorrows is the light-emitting diode. LEDs are rapidly replacing bulbs and tubes because they are more efficient.新式的照明技术是发光二极管(LED),LED正凭借其更高的能量利用率迅速取代电灯泡和灯管。And because they are semiconductor devices, tinkering with their electronics to produce the flickering signals required for data transmission is pretty straightforward, according to Gordon Povey, who is working on light communication with Harald Haas and his colleagues at the University of Edinburgh, in Britain.歌登?波文在英国爱丁堡大学与哈拉尔德·哈斯及其同事一起研究光通信;他说,因为LED是半导体器件,调整一下其电路就能很轻易地产生传输数据所需的闪光信号。The rate of data transfer is also good.用可见光传输数据的速度也相当可观。Dr Poveys group is aly up to 130 megabits a second (faster than some older Wi-Fi routers) over a distance of about two metres, using standard LEDs.波文士的研究小组已能利用标准LED在约两米内以最高每秒130兆位的速度(比一些老式Wi-Fi路由器还快)传输数据。Dr Povey, who is also the boss of VLC, a firm set up to commercialise the technology, thinks such devices should be able to reach 1 gigabit per second (Gbps), and do so over greater range.同时也是VLC公司(为使这种技术商业化而成立的公司)的老板的波文士认为这种器件应能达到每秒1千兆比特(Gbps)的传输速度,且传输距离可以更远。Specially constructed LEDs would be even faster. The Li-Fi consortium reckons more than 10 Gbps is possible.采用特制LED所达到的速度将会更高。Li-Fi联盟估计传输速度可能达到10 Gbps以上。In theory, that would allow a high-definition film to be downloaded in 30 seconds.理论上,这个速度意味着不到30秒就能下载一部高清电影。Dr Povey believes that adapting existing LEDs to work with the sensors and light sources-cameras, ambient-light detectors, screens, flashbulbs, torches and so on-aly found in smartphones and similar devices will be the fastest way to bring Li-Fi to market.波文士认为,改造现在的LED使之适应智能手机及类似设备上已有的感应器及光源,如摄像头、环境光感应器、屏幕、闪光灯泡、手电筒等,是将Li-Fi推向市场最快的方法。VLC has aly produced a smartphone app which allows low-speed data transmission between a pair of iPhones.VLC已设计了一款智能手机软件,两部iPhone能用此软件以低速传输数据。It has also made an experimental optical transceiver that plugs into a laptop to receive and send light signals.该公司也制造了一台用作试验的光收发器,可插入笔记本电脑以收发光信号。Later this year it will bring out Li-Fi products for firms installing LED-lighting systems.今年再过不久,VLC将面向安装了LED照明系统的企业推出Li-Fi产品。There are limitations to using light, of course. Unlike radio, light waves will not penetrate walls.当然,利用可见光通信也存在局限性。可见光不同于无线电波,无法穿透墙壁。Yet for secure applications that could be a bonus.但对于安全应用而言这可能是个意外的优点。And light bulbs—some 14 billion of them around the world-are almost everywhere and often on.而全球大约共有一百四十亿个灯泡,它们几乎随处可见,而且经常亮着。As they are gradually replaced by LEDs, every home, office, public building and even streetlight could become a Li-Fi hotspot.随着电灯泡逐渐被LED所取代,每家每户、办公室、公共建筑物、甚至路灯都可能成为一个Li-Fi热点。Having a line-of-sight connection with the LED in question would undoubtedly improve the signal, but light reflected from walls or ceilings might often be enough.若你正在使用的LED光源处于视线范围内,信号强度无疑会有所增加,不过仅靠墙壁或天花板的反射光可能往往也足够了。In any case, having a good line of sight helps Wi-Fi as well. And spotting a nearby light in order to sit next to it is certainly easier than finding the location of a Wi-Fi router.同样,不论如何,若在视线之内有Wi-Fi信号源,信号当然也会更强。而在身边找一个光源就近使用之当然要比寻找Wi-Fi路由器来得容易。Communication, though, is a two-way street. That means the LEDs involved in Li-Fi would need photodetectors to receive data.不过通信是双向的。这意味着Li-Fi中的LED需要有光电探测器来接收数据。Some LED systems have such sensors aly (to know when to turn on at night).一些LED系统已经配备这种探测器了(以便在夜间判断何时开灯)。But even if LEDs are not modified Dr Povey reckons hybrid systems are possible: data could be downloaded using light but uploaded (typically a less data-intensive process) using radio.但即使不对LED进行改造,波文士认为混合系统也可能行得通:通过光下载数据,而上传数据则使用无线电波(这一过程的数据量通常小些)。In an office, for example, an LED-powered desk lamp could work as a Li-Fi router, able to link up with any networked device placed on the desk.例如在一个办公室里,一盏LED台灯也可以是一个Li-Fi路由器,它能连接桌上任何一个已经联网的设备。A big advantage of light is that it can be used in areas which contain sensitive equipment that radio signals might interfere with, such as aircraft and operating theatres.可见光通信的一大好处在于:它在装有可能会受无线电信号干扰的敏感设备的场所能派上用场,如飞机上及手术室内。LEDs in the ceiling of an airliner would not only allow internet access but could also transmit films on demand to individual seats, removing the need for lots of expensive and heavy cabling, thus saving airlines fuel.将LED安装在大型客机的舱顶,不仅能提供网络务,还能将旅客点播的电影传送至他们的座位上,这样就不必安装许多昂贵而又笨重的线缆,如此一来也会节省燃油。That alone could be enough to, as it were, make this idea fly.光是这一点,似乎就足以令这项技术腾飞。 /201209/201876南平哪个医院检查不孕 Books and Arts; Book Review;Bulgakov and Stalin on stage;文艺;书评;舞台上的布尔加科夫与斯大林;Men and monsters;Two new plays explore the relationship between art and tyranny;人与怪物;探讨艺术与极权统治之间关系的两部新剧;Even without the constraints of censorship, Stalins reign lends itself to surrealism. How else to convey its mad caprices, the incomprehensible scale of his cruelty and the spiralling paranoia? Two new London productions that, coincidentally, involve Stalin and the novelist Mikhail Bulgakov, make apt use of surreal fantasia. Catch either, or ideally both, if you can.即便没有审查制度,斯大林的统治之下,艺术也会走向超现实主义。不然还有什么方式,可以表达其统治的反复无常,以及其人不可理解的残酷程度和日益增强的偏执呢?伦敦最近的两部新剧,恰好以超现实的幻想曲,让斯大林和小说家米哈?布尔加科夫走到了一起。两者中任一方面都值得玩味,如果你能,也可以兼顾双方。The new version of “The Master and Margarita” by Complicite, a British company justly renowned for its daring theatre, is set to tour Europe after a short, triumphant run at the Barbican. The unwieldy zaniness of Bulgakovs great novel—whose action involves the devil and his retinue visiting Stalins Moscow, the blighted affair of the eponymous characters, and the masters novel about Pontius Pilate and Jesus—somehow hasnt deterred stage adaptations. In this one, Simon McBurney, Complicites director, doubles down: rather than trying to simplify, he mashes up the stories, echoing and embellishing them in multimedia. There are projections, sound loops, puppetry and nudity: a painfully emaciated Christ; a flying, nude Margarita.以大胆的舞台著称的英国Complicite公司推出了新版《大师与玛格丽特》,在巴比肯的短暂上演大获成功,计划接下来去欧洲巡演。布尔加科夫这本伟大的小说带有一种不受配的癫狂:魔鬼极其随从造访斯大林的莫斯科,同名人物的事迹以及大师所著关于比拉多和耶稣的故事。但这些都没有阻碍舞台剧本的改写。Complicite公司的总监Simon McBurney认为,不应当简化原著,而是把整个故事融为一体,并通过多媒体手段加以呼应和装饰。电脑投影,环绕音响,木偶人像和大胆裸露都得以应用。瘦骨嶙峋的耶稣痛苦地受难,还有赤身裸体悬在空中的玛格丽特。The result is a dark carnival of theatrical effects, which is demanding, sometimes overwhelming, only occasionally misfiring. Like ers of the book, some members of the audience may yearn for more of the comic demons, in particular the giant, lecherous cat. But the overall impact highlights the novels underlying themes: the hypocrisy of many but compassion of some; the way craven people get the callous rulers they deserve, yet now and then rise to a nobility that deserves better.这一切的结果便是各种舞台特效在黑暗中的狂欢。全场气氛被跳动起来,有时甚至无法抵抗,只有某些时刻会显得过火。和原著的读者一样,现场的一些观众可能也会渴望看到更多动画制作的怪物,尤其是那只巨大的充满色情意味的猫。但总体效果还是突出了小说暗藏的主题:多数人的伪善和少数人的悲悯;懦弱的民众从暴君是自食其果,虽然不时的那点高尚,似乎值得更好的统治。“Collaborators”, a coruscating new play at the National Theatre, imagines a relationship between Stalin and Bulgakov himself. Directed by Sir Nicholas Hytner and written by John Hodge, previously best known as the screenwriter for “Shallow Grave” and “Trainspotting”, the production will soon transfer to the Nationals main Olivier stage after opening at the smaller Cottesloe. Bulgakov (Alex Jennings) is coerced to write a play about the dictators early years to celebrate his 60th birthday. In return, along with his life and his wifes, he is promised the un-banning of his subversive drama about Molière—grotesque, masked scenes from which intrude on the main story, as do comically appalling passages from the Stalin tribute.在国家剧院上演的《合作者们》也是一部引人注意的新剧,假想了斯大林与布尔加科夫之间的故事。导演是Nicholas Hytner,编剧是John Hodge,之前凭借《浅坟》和《猜火车》为人所知。这部新剧在Cottesloe开演之后,很快会转至更大的国家奥利弗主剧院演出。剧中布尔加科夫(Alex Jennings饰)被迫写一部关于独裁者早年经历的剧本,以庆祝他的60岁诞辰。回报就是他得到允诺,他关于莫里哀的反动剧作不会被禁演。于是这个剧作中的奇怪晦涩的场景会不时插入到为斯大林献礼的剧作中,传达出既滑稽又恐怖的信息。That, in the event, is written by Stalin, who summons Bulgakov to secret meetings. The actual Bulgakov did write a never-performed play about Stalins youth; Stalin telephoned and took an interest in him, though there is no record that they met. Simon Russell Beale (pictured above) is a chillingly hilarious Stalin; substituting a West Country burr for the original Georgian accent, he is cunning and charming, manipulative, menacing and intellectually insecure. While Stalin hammers out the script, Bulgakov, struggling with his compromises and conscience, is obliged do his collaborators paperwork, which slides from steel-factory targets, to grain allocations, to death as.这一段在剧中,是由斯大林所写,他召见布尔加科夫密见。现实中布尔加科夫的确写过一部关于斯大林青年时期经历的剧本,但从未被搬上舞台。斯大林和他通过电话并表示过赞赏,但并没有他们会面的记录。Simon Russell Beale(如图)扮演了一个冷酷却又惹人发笑的斯大林,用西方粗喉音代替了他原来的乔治亚时期的口音。他世故圆滑,富于魅力,控制欲强,具有威慑力同时又反复无常。在剧中,当斯大林敲定剧本台词时,布尔加科夫在妥协和良知之间摇摆挣扎,但不得不完成这一合作的剧本,内容涉及炼钢厂目标,谷物分配,甚至死刑名额。Both productions explore the relationship between tyranny and creativity: the artistic kind, but also the humbler urge to create private love and lives in crushing times. “The Master and Margarita” proclaims that “manuscripts dont burn”. “Collaborators” is less sure of arts resilience: “the monster always wins”, Stalin insists. “Collaborators” hints at the structural similarities between writing and governing. Both are lonely work, requiring the imposition of an arbitrary order on unseen, notional individuals—only, in the case of the tyrant, the people are real.两部新剧都探讨了集权统治和艺术创造之间的关系:在集权压制的时代,关于个人情爱和生活的艺术创作的动力极其微弱。《大师与玛格丽特》宣称“手稿不可被真正焚毁”。《合作者们》则并未如此确定艺术的自我恢复能力,毕竟“怪物们总是胜利”,这是剧中斯大林坚持的台词。这两部作品都算是脱离现实,涉及到对那些未见的个体施加强制命令,只有在暴君统治之下,居中的人民才活在真实当中。 /201209/200626三明市看不孕费用

福州清宫手术的医院福州去那里人工授孕好 Can I touch them?-Yeah.我能碰它们吗?可以。Will they peck me?它们会啄我吗?Theyll peck at your rings.它们会啄你的戒指。They really?真的会吗?And theyll try to take them off if theyre gonna get hold. But they are not very strong at pecking.如果你抓紧戒指的话,它们还会试图把它脱下来。但是它们不会用劲啄。I want to feel your feathers. Now this might be what a dinosaur felt like to touch. Thats really soft and lovely. 我要抚摸你的羽毛。现在这也许和触摸恐龙的感觉一样。它们真的很柔软很可爱。Yes, just like a cuddly toy.对,就像毛绒玩具一样。Oh, Im stroking dinosaurs. Yeah, get it off me. I think they too little like dinosaurs especially when you know that some dinosaurs were actually feathered.啊,我在抚摸恐龙。好的,放开我。尤其是当你知道一些恐龙实际上长有羽毛,你就会觉得它们不像恐龙了。They certainly do. And those feathers are quite primitive and they structure a lot like some of the fossil feathers we find.它们当然是恐龙。而且这些羽毛也相当原始,跟我们找到的羽毛化石结构很相似。The similarities arent just on the surface. We can get a much better understanding of ancient dinosaurs by looking at the anatomy of their modern relatives in depth. And a local farm has recently had to put down one of its ostriches. As an anatomist, Im very used to dissecting cadavers.相似之处并不仅仅只停留在表面。我们可以通过深入观察恐龙现代亲戚的解剖图来更好地了解恐龙。近来一家当地农场不得不了结一只鸵鸟。作为一个解剖学家,我经常解剖尸体。You know, I dont usually wear Wellington boots when I do dissecting. But this will be the first time that Id ever dissected a bird, or for that matter, the descendant of a dinosaur. Why dont you talk me through the anatomy that we can see on the surface?你也知道,我在解剖时不常穿惠灵顿长靴。但这将会是我第一次解剖鸟类,也可以说是我第一次解剖恐龙的后代。为什么你不详细地为我介绍一下表面的解剖?Thats a heel, the ankle joints. But birds walk with that, clear the ground, just like their dinosaur and ancestors did. 这是脚跟,这个脚踝关节。鸟类依靠它行走,清理地面,正如它们的祖先恐龙那样。And Really? Just two toes? And one main one?真的吗?只有两根脚趾头?主要的那根指头呢?The middle toe is their dominant toe, just like, you know, a dinosaur, the third toe is the major toe of the foot.中间的指头是最重要的,同理,对于恐龙来说,第三个脚趾才是最重要的。And there are other similarities to their ancient relatives.鸟类与它们的古代亲戚还有其它的相似之处。原文译文属!201210/204253福州造影那家医院最好

龙岩什么医院做复通手术 Im starting in the south.我将从南方开始。For many visitors, it is Spain.对于许多游客来说,它是西班牙。But away from the beaches, these are magnificent sights.但远离海滩,壮观的景色呈现在人们眼前。Grand palaces, castles, and masks, remind us of a different culture from a distant time, a time when Spain was called Al-Andalus.宏伟的宫殿、城堡和面具提醒着我们在遥远的过去有着截然不同的文化,当时西班牙被称为Al-Andalus。What is often forgotten is over 700 years mush of Spain was ruled by Muslims, and the South was its beating heart.而常常被人遗忘的是超过700年统治西班牙的是穆斯林,而南方是它跳动的心脏。Southern Spain was an unique frontier where east met west with explosive results.西班牙南部是东方和西方的爆炸性结果的一个独特的前沿。This is the story of how Islamic Spain became one of the most remarkable civilizations ever seen.这个故事就是伊斯兰西班牙如何成为最非凡的文明。注:听力文本来源于普特201211/207259博爱医院做人授要多少钱福州博爱不孕不育封闭抗体检查多少钱



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