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2019年11月18日 15:42:20

Science and Technology New transistors Mechanical advantage科技 新型晶体管 机械优势Two new types of transistor may lead to simpler, more efficient computers两种新型晶体管或许会导致更加便捷高效计算机的出现WHEN baking a cake it helps to have all the ingredients within reach, rather than wasting time and energy making frequent trips to the pantry.当你在烧烤蛋糕的时候,它有会让所有的一切都变得触手可及,而不是让你在食品柜繁琐的开关之间浪费时间与精力。Something similar is true of the logic circuits in computers microprocessors.这也同样会真正应用于电脑微处理器中的某些逻辑电路。These could be made faster, and would consume less energy, if they were able to store information themselves instead of fetching it from separate memory chips or hard drives.如果这些微处理器自己能够储存一些信息,用来取代从原来相互独立的芯片或手工操作中获得的信息,它们的速度将会变得更快,能耗将会更低。The problem is that the transistors used to make logic circuits hold their electronic state, and therefore any data they contain, only when powered up.问题是,用来制造逻辑电路的晶体管中保留着它们的电子态,因此当这些晶体管通电的时候,它们会包含任何可能的数据。The choice engineers face is thus between supplying continuous power to a transistor, so that it can retain its memory (which costs energy), and ferrying data that would otherwise be lost to and from so-called non-volatile memory devices that do not require continuous power (which costs time).因此,工程师们面临的选择就是要么对晶体管提供一个持续的电源,让晶体管保持自己的记忆(这会耗费能源),否则从所谓的非易失性半导体存储器中传输的数据就有可能丢失,不过它不需要持续的电源(这会消耗时间)。Cracking this problem—so that transistors can act as their own non-volatile memory—would make all computers faster.解决这个问题——以便于让晶体管使用自身的非易失性半导体存储器——将会让所有的电脑运行速度更快。It would be particularly valuable, though, for mobile devices.虽然这对于移动设备来说,显得特别昂贵。These could be made smaller and lighter, since they would require fewer components.不过移动设备因此可以做得更小,更轻盈,因为它们需要的元件更小。And they could go for longer between charges.并且两次充电的时间间隔将会变得更长。To this end, Hiroshi Mizuta of the University of Southampton, in England, and Tsuyoshi Hasegawa of the National Institute for Material Science in Tsukuba, Japan, are proposing a marriage between two novel types of transistor that could hardly be more different.为此,英国南安普顿大学的Hiroshi Mizuta和日本筑波国立材料科学研究所的Tsuyoshi Hasegawa提出了将两种完全不同新型材料混合起来。One, the atomic transistor, draws on the latest advances in nanoscience.其中一种就是原子晶体管,它利用了最新的纳米科技。The other, the mechanical transistor, sounds as if it has been lifted from the annals of the industrial revolution.另外一种就是机械晶体管,这听起来就像是从工业革命史册中发掘出来的玩意儿。The atomic transistor works, as its name suggests, by shuffling individual atoms around within the device.原子晶体管的工作方式就像它名字所示的那样,是通过移动该元件内部的单个原子进行工作的。The atoms in question are copper,这里所说的原子指的是铜原子,and the result of the shuffling is to create or destroy a conductive pathway between two crucial bits of the transistor, the source and the drain, thus switching the device on or off. That is possible because this part of the transistor is made of tantalum pentoxide, a material whose atoms are arranged in a lattice which contains holes large enough for copper atoms to squeeze through.移动的结果主是在晶体管的两个十字位置构建或消除一个传导通路,它的源极和漏极因此就会开启或关闭。这是有可能实现的,因为这部分晶体管是由五氧化二钽制造的——这种材料可以将它自身的原子排布在晶格中,这些晶格包括一些足够大的孔,可以让铜原子挤过去。The mechanical transistor, more properly called a nano-electromechanical systems (NEMS) transistor, creates and destroys the connection between source and drain mechanically.机械晶体管,更确切地可以称之为纳米电子机械系统(NEMS)晶体管,它可以在源极和漏极之间机械地构建或消除连接。When a voltage is applied across two beamlike electrodes made of aluminium, which are separated by a gap of around 50 nanometres, charge builds up on each, creating an attractive force between them, until a critical point is reached.两个柱状的铝电极间隔约50纳米,当电压加在这两个电极之间时,它们就会相互通电,在二者之间会形成一股引力,直至达到一个临界点。At that moment one of the electrodes flips towards the other, causing the two to make contact. This closes the circuit and turns the transistor on.在达到临界点的那一刻,其中一个电极就会移向另一个电极,这两个电极就会形成通路。Apply the opposite charge and the electrode flips back, breaking the circuit.这样就会接通电路,打开晶体管。利用相反的电荷,电极就会复位,进而断开电路。What makes these two very different types of transistor attractive is that both the copper and the aluminium stay put when the power is turned off.这两种完全不同类型的晶体管如此吸引人的地方就在于断电后,如何让铜原子和铝电极待在原地。They can thus act as memories as well as processors.它们可以应用于储存芯片和处理器。The ;on; state represents one type of binary digit (a one, say) and the ;off; state represents the other (zero).;开;的状态表示二进制中的一个数字(就是;一;),;关;的状态可以表示另一个数字(即;零;)。Dr Mizuta and Dr Hasegawa are therefore using the novel transistors to try to make the worlds first non-volatile processor chip.Mizuta士和Hasegawa士因此都在使用新型的晶体管,力图制造出世界上第一个非易失性处理器芯片。Ideally, such a chip would have only one sort of transistor, since that would mean it was much easier to manufacture.理想的这种芯片将只有一种晶体管类型,因为这意味着它将会更加容易制造。However, transistors come in two varieties, n-type (negative) and p-type (positive).不过,晶体管却有两种,一种是N型(负),一种是P型(正)。Both are needed in a logic circuit, but atomic devices can be only n-type.逻辑电路都需要这两种晶体管,不过在原子设备中,只需要N型。The alternatives, then, are to make the circuit entirely out of NEMS transistors, or to mix the two by using atomic devices where an n-type transistor is needed and NEMS ones where a p-type is required.那么另一个方案就是完全用NEMS晶体管制造电路,或者是将利用N型晶体管的原子设备和利用P型晶体管的NEMS晶体管混合起来。Dr Mizuta and Dr Hasegawa have opted for a mixture, because atomic transistors are much smaller than NEMS ones, and the saving of space outweighs the awkwardness of mixing them together.Mizuta士和Hasegawa士选择了二者的混合,因为原子晶体管比NEMS更加小巧,这样节省的空间就会消除二者的混合的尴尬。If their recipe works, it will mean far fewer electronic trips to the pantry and a quicker baking time for whatever answer the new chip is trying to cook up.如果他们的方案成功的话,这意味着食品柜中的开关将会大大减小,(无论任何口味的饭菜)实现更短的烹饪时间。 /201211/210629和田脱小腿毛多少钱Still in Books and Arts; Book Review;Foreign interventions;When to hold and when to fold;文艺;书评;来自外国的干扰;来自外国的干扰究竟该如何进退;Can Intervention Work? By Rory Stewart and Gerald Knaus.《干预有用吗?》Rory Steward, Gerald Knaus合著。Can we intervene in foreign countries and do good? Can we stop wars and genocides and get rid of evil dictators? Can we then build modern, democratic states that thrive in our wake? The answer depends on who you ask. An anti-Qaddafi Libyan will have nice things to say about NATOs role there right now. But you will get very different views from an Afghan, an Iraqi, a Bosnian or a Kosovar.我们有权干预外国吗?我们的干预真的有利吗?我们能够阻止战争和屠杀吗?我们能够消灭掉那些邪恶的独裁者吗?我们能够激发他们的斗志,促使他们建造一个现代的民主国家吗?这些因人而异。谈起北约在推翻其政权中起到的重要作用,一个反对利比亚卡扎菲政权的人立即就滔滔不绝。但是如果你问一个阿富汗人,伊拉克人,波斯尼亚或是科索沃人,得到的就会大不相同。Rory Stewart and Gerald Knaus are well placed to pose and answer these questions. Before Mr Stewart became a Conservative MP, he was a deputy governor of two Iraqi provinces. He also walked across Afghanistan and wrote a bestseller about the experience. Mr Knaus, a political economist, runs the European Stability Initiative, a Berlin-based think-tank founded in Sarajevo in 1999, which has been particularly influential in the Balkans.Rory Stewart 和 Gerald Knaus根据自身的经历,给出了合宜的。在Stewart成为一个保守党议员之前,他曾担任过伊拉克两个省的省长。他还曾横穿阿富汗,将自己的经历写成了书,并成为了畅销书。Knaus则是一名政治经济学家,他管理一家位于柏林的智库,叫作欧洲稳定计划。其于1999年创建于萨拉热窝,在巴尔干半岛各国特别有影响力。The book is structured as two essays with a lengthy joint introduction. Mr Stewart has written a colourful account of his time in Afghanistan and his failed attempts to stop what he sees as a self- defeating build-up of ambitions, troops and plans. He skewers gobbledygook notions of bringing Afghans accountable governance and Western-style rule of law. It is not that he is against such things, but that he doubts the ability of foreigners to impose it all. He cites a pragmatic admonition from English Mountain Rescue: “Be prepared to turn back if conditions turn against you.”本书由2片论文及一篇很长的合序构成。Stewart描绘了他在阿富汗时多姿多的生活,也写了他对阿富汗一系列的雄心壮志,军队的建立以及计划的制定的看法,认为这都是自拆台脚,他想要阻止却未能成功。他竭力讥讽那些官腔,说什么建立一个可信赖的阿富汗政府,引进西方式法治。他并不是反对这些做法,而是质疑外国人的执行力。他在此引用了英国高山救援队的一条朴实的警告;“如情况不利,请准备回程。”Writing about Bosnia, Mr Knaus deploys heavy artillery in arguments that he has made before. Intervention there has been a stunning success, he says, given the state of Bosnia at the end of its devastating war in 1995. Hundreds of thousands of refugees have returned, not a single intervening soldier was killed (after the war), and todays problems are of the conventional political sort, not the kind that herald another war. Not only does Bosnia enjoy free and fair elections, but also it has relatively little crime. Mr Knaus argues that the only missteps came from assumptions held by those like Lord Ashdown, when he was de facto governor of Bosnia, that well-meaning envoys could behave like imperial viceroys, sacking elected yet obstructive leaders at will.谈到波斯尼亚时,Knaus大量引用了他之前发表的观点,火力十足。鉴于那场1995年波斯尼亚发生的残酷的战争的结局,干预确实取得了惊人的成功,他说。成百上千的难民都回归故土,且没有一个外来士兵死于战后重建工作中。但是今天的问题是常规政治,并非预示着另一场战争的那种。不仅波斯尼亚有了公平自由的选举,而且犯罪也相对减少。Knaus认为,唯一的错处在于阿什当勋爵等人的错误假设。阿什当勋爵为波西尼亚实际领导人时,满怀善意的使者却能像帝国总督那样,任意将选举出来却碍手碍脚的领导人撤职。From rather successful interventions, defined as Bosnia and Kosovo, the authors convey an important lesson: that is, the experience garnered in one place is generally not much use elsewhere. Bosnia was a success because the intervention came as part of the 1995 Dayton peace agreement, which ended the war and which all the exhausted sides committed themselves to. In Kosovo the vast majority of its people—ethnic Albanians, nearly all of them Muslims—were very grateful for what they saw as their America-led liberation from the Serbs. Mr Knaus also argues that the ed Nations war-crimes tribunal was vital as a form of closure and for removing from the political scene characters such as Ratko Mladic, a Bosnian Serb general now on trial for genocide in The Hague.从波斯尼亚、科索沃等干预的成功案例中,作者得出了一个重要的结论,那就是,从一处获得的经验多数时候在其他地方并不管用。波斯尼亚干预的成功是因对其干预是作为1995年代顿和平协议中的一部分提出的,协议旨在结束战争,而精疲力竭的双方也都愿意遵守。而在科索沃,大多数国民为阿尔巴尼亚人,几乎所有人都是穆斯林,他们十分感激美国领导他们从塞尔维亚人手中解放。Knaus还谈到,联合国军事法庭对于消灭拉特科·穆拉迪克这样的人至关重要。Ratko Mladic是波斯尼亚的塞尔维亚将军,如今因涉嫌种族灭绝而在海牙国家法庭受审。So, does intervention work? As any Bosnian peasant may tell you, “maybe yes, maybe no.” It depends on the circumstances and requires modest ambitions. Muddle through with a sense of purpose, says Mr Knaus. Do what you can, where you can and no more, agrees Mr Stewart. In policy terms that sounds a bit like “yes” to Libya, “no” to Syria and so on.那么,干预究竟是否有用呢?随便哪个波斯尼亚的农民都会这样告诉你,“可能有用吧,也可能没用。”它取决于现实情况,并且人们的目标也要合理。有目标地混日子,Knaus如是说道。你想做就做,能做就做,没别的了,Stewart以此表示赞成。从政策的角度来看,这似乎是在对利比亚称好,对叙利亚摇头之类的。 /201304/233170新疆军区总医院祛痣多少钱Business.商业。Personalising online prices.个性化网购价。How deep are your pockets?你的钱包有多鼓?Businesses are offered software that spots which customers will pay more.能发现愿意多付钱客户的软件现可供企业使用。IN MANY types of face-to-face retailing, it pays to size up your customer and tailor your offering accordingly. In a 2006 study of Fulton fish market in New York, Kathryn Graddy of Oxford University found that dealers regularly charged Asian buyers less than whites because the Asians had proved, over time, more willing to reject high prices, and ier to band together to boycott dealers who ripped them off.在许多面对面的零售过程中,揣测客户需求并对其进行针对性销售往往会得到应有的回报。根据2006年牛津大学Kathryn Graddy对纽约Fulton海鲜市场的研究,跟白人相比,卖家经常以更低的价格卖给亚洲人。因为经验显示亚洲人更容易对高价产生反感,而且更愿意很快地联合起来抵制奸商。The internet, by allowing anonymous browsing and rapid price-comparing, was supposed to mean low, and equal, prices for all. Now, however, online retailers are being offered software that helps them detect shoppers who can afford to pay more or are in a hurry to buy, so as to present pricier options to them or simply charge more for the same stuff.具有隐身浏览和快速价格比较功能的互联网,本应代表着所有人都能享用低廉,平等的价格。然而现在,网上零售商可利用软件帮他们筛选出更有承受能力或急着埋单的消费者。对应地,零售商可推荐更昂贵的商品或直接将同样的商品标更高的价格。Cookies stored in shoppers web browsers may reveal where else they have been looking, giving some clues as to their income bracket and price-sensitivity. A shoppers internet address may be linked to his physical address, letting sellers offer, say, one price for Bel Air, another for Compton. Doug Bryan of iCrossing, a digital-marketing consultancy, explains that the most up-to-date “price customisation” software can collate such clues with profiles of individual shoppers that internet sellers buy from online-data-aggregation firms. All this is fairly cheap, he says.存储在消费者浏览器内的小型文字档案(Cookie)可能透露了他们曾经逛过哪里,并提供了估算他们收入状况和价格敏感度的信息。一名消费者的网络地址可以跟所在地地址联系在一起,这让卖家给贝沙湾(Bel Air洛杉矶富人区)可标一个价,给康普顿(Compton肯塔基州穷人区)标另一个价。数字市场营销咨询公司iCrossing的Doug Bryan解释称,时下大多数;个性化价格;软件可以使用自身收集的数据对网络卖家从其他在线数据汇总企业的数据进行校验。而且他称这一切都十分便宜。One of the few big online firms to admit to using such techniques is Orbitz, a travel website. Its software detects whether people browsing its site are using an Apple Mac or a Windows PC and, since it has found that Mac users tend to choose pricier hotels, that is what it recommends to them. Orbitz stresses that it does not charge people different rates for the same rooms, but some online firms are believed to be doing just that, for instance by charging full whack for those assumed to be willing and able to pay it, while offering promotional prices to the rest.其中一个少数承认使用该手法的大型网络旅行社企业是Orbitz。公司使用的软件检测用户究竟是用苹果电脑还是普通电脑浏览公司网站。因为公司发现用苹果电脑的用户更倾向选择更贵的酒店,所以网站也应势推荐给他们。Orbitz强调他们绝对没有同房不同价,但是人们相信一些网上公司就是这么操作的。例如对那些有能力也愿意付全价的用户则收全价,而对其它用户打更多折扣。Allocating discounts with price-customisation software typically brings in two to four times as much money as offering the same discounts at random, claims Ravi Vijayaraghavan of [24]7, a Bangalore-based firm that develops and operates such software. One way to do this is to monitor how quickly shoppers click through towards the online sellers payment page: those who aly seem set on buying need not be tempted with a special offer. Firms like [24]7 and RichRelevance, another price-customisation software firm, from San Francisco, are somewhat keener to talk about their software than the internet retailers who are trying it out. Mr Vijayaraghavan names ed Airlines, for example, as among his big clients, but the airline declined to comment for this article.基于班加罗尔开发和运营这种软件的公司[24]7,该公司Ravi Vijayaraghavan称,通过个性化价格软件来分配折扣,通常可以带来比随机分配折扣多两到四倍的营业额。其中一个方法是监测消费者在网站点入付账页面的速度:那些看起来已经决定了的买家不需要通过特价来吸引。另一家来自三藩市的价格个性化软件公司RichRelevance和[24]7公司一样,它们跟尝试软件的网上零售商相比,感觉更愿意畅谈这类软件。Vijayaraghavan称联合航空(ed Airlines)便是他们其中一个大客户。然而该航空公司拒绝对此文章置评。Andrew Fano, a consultant in Accentures Chicago office, reckons that at least six of Americas ten biggest web retailers are now customising prices in some way, but it is hard for shoppers to spot when this is going on. If they knew, many would feel that it is ;pushing the boundaries; of fairness, notes Werner Reinartz, a University of Cologne marketing professor and consultant to two Fortune 500 companies that use customisation techniques.埃森哲咨询公司(Accenture)芝加哥分部的顾问Andrew Fano称,美国最大的十家的网络零售商中,最少六家现在或多或少地在使用个性化价格,但消费者本身很难发现自己所在的处境。如果他们知道,很多人将感觉在试探公平原则的底线。这是由Cologne大学市场营销教授Werner Reinartz提出的,他同时也是财富500强里两家使用价格个性化技术公司的顾问。Mr Reinartz preaches caution lest companies be dragged through an ordeal pioneered by Amazon in the autumn of 2000. Word broke that the internet giant was selling DVDs at differing prices, to see which web browsers happened to be favoured by shoppers least concerned about cost, former executives say. The resulting backlash prompted it to refund those who paid more, and Amazon now declines to discuss its pricing system.Reinartz提醒公司要预防陷入2000年秋亚马逊为此成为先烈的经历。时任总裁称,在网上流传这家互联网巨头以不同价钱卖DVD,用来分析哪个浏览器的用户更不在意价格。引起的反弹致使公司给多付钱的客户退款,亚马逊现已拒绝对其标价系统置评。Users of price-customisation software have so far been reluctant to peep at potential customers social-media pages, for fear that this would provoke a privacy backlash. But the operators at the call centres [24]7 runs for its clients are beginning to scan Twitter for gen on the shoppers they are talking to—and sometimes, says Mr Vijayaraghavan, their tweets give useful hints about whether a discount is needed to clinch the sale.个性化价格软件的用户至今还不敢窥视潜在客户的社交网页,因担心这将引起关于私隐的反弹。但24[7]公司中心的客户代表,已经开始代客户在Twitter上追溯消费者聊天的关系网。Vijayaraghavan称,有时候用户的微会透露究竟是否需要折扣来达成交易。 201208/193143乌鲁木齐县治疗痤疮多少钱

乌鲁木齐激光祛除肥胖纹乌市高新技术产业开发区自体脂肪移植丰胸哪家好I know you wont believe this, but I really did that.我知道你不会相信这个,但是我真的是那样做的。It took me 50, 53 minutes.我花了50,53分钟。Thats eight minutes more than Vincent.那是比文森特多的八分钟。And he used to do it twice a day, strolling to work, strolling back.而他过去常常一天做两次,漫步去工作,之后散步回来。He worked just there, at Goupils which is a noodle restaurant now.他就在那里工作, 现在那里是一家面馆。He used to selling prints and earning 90 pounds a year.他过去常常销售印刷品,而每年的年薪能够达到90英镑。Its actually a very good salary in those days about the average payment for a laborer.这在那些日子里大约对于平均付的劳动者来说实际上是一笔非常不错的薪水。The wandering minstrel, I我这个流浪的歌手。A thing of shreds一件事的碎片And patches和补丁Van Goghs favorite English writer was Dickens.梵高最喜欢的英国作家是狄更斯。He most of the novels, and then re them.他最常读的就是他的小说,然后重读它们。He was always ing Dickens in his letters, gobbling up Dickens sympathy for the London poor, all those blighted Oliver Twists scrounging in the streets.他总是在他的信中引用狄更斯,狄更斯同情伦敦贫民,所有的那些奥利弗在街上乞讨的波折。Dickens opened Vincents eyes to modern human misery.狄更斯为文森特打开了对于现代人类苦难的双眼。Dickens died in 1870, just before Vincent got here.狄更斯死于1870年,就在文森特到达这里前。注:听力文本来源于普特201207/189611北屯市膨体隆鼻多少钱阿图什市去除眉间纹手术多少钱

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