2009年11月30日 星期一

Smart Grid Standards

Michael Kanellos | November 23, 2009 at 2:01 PM 9 Comments

The Biggest Thorn for Smart Grid Standards? The Home Area Network

The National Institute of Standards and Technologies is busy on one of the most ambitious standards programs in the history of technology: it wants to set 77 standards for the smart grids, including standards for 14 priority areas.

And it wants a number of the important standards, such as demand response monitoring and energy use information sharing, done in a few months.

This is not going to be easy. Some technology standards bodies can linger for years.

Last week, I sat on a panel with George Arnold, who heads up the project for NIST, at the GreenBeat Conference and asked him which are the ones that look like the biggest problems.

Surprisingly, he said home area networks. Homes should be easy to control, right? They only have a few hundred to a few thousand square feet and contain a finite number of appliances which get replaced at a fairly slow rate.

The challenge lay in achieving cooperation. Appliance makers are nervous about added costs. No single standard--ZigBee, WiFi, power line networking, some form of RF mesh--has won out yet and interoperability remains a work in progress. Different camps continue to promote different paradigms for home energy control. For hardware makers, this adds up to compounded risks.

How NIST gets through this will be one of the biggest issues next year in smart grid.



米国標準技術局(National Institute of Standards and Technologies:以下「NIST」:関連リンク)はいま、科学技術の歴史のなかでも最も野心的な標準づくりで多忙を極めている。NISTではスマートグリッド関連の77の標準を定めたい考えだが、このなかには特に重要な14分野の標準も含まれる。

NISTはまた、たとえばディマンド・レスポンスの監視関連や、エネルギー利用状況についての情報の共有に関するものなど、多数の重要な標準を今後数ヶ月間で定めたいと考えているが、これは簡単に片付かないだろう。技術標準づくりには何年もかかる場合もあるからだ。

先週開かれたGreenBeat 2009カンファレンスのあるパネルディスカッションで、私はNISTでスマートグリッド関連の標準策定プロジェクトを率いるジョージ・アーノルド (George Arnold)と一緒になった。そこで私は「どの分野がもっとも厄介そうか」と同氏に訊ねてみた。

「家庭内ネットワークに関連するものだ」と同氏は意外な答えを口にした。家庭(個人宅)は管理が用意なはずではなかったのか。家庭の場合、広さは数 百平方フィートから広くても数千平方フィートで、電子機器や家電製品の数も限られており、しかもそれらはかなりゆっくりしたペースで買い換えられる。

アーノルドによれば、この原因は関係当事者間の調整が難しい点にあるという。たとえば家電メーカー各社は製品のコスト増につながることに神経をとが らせている。また、通信に関しても、ZigBeeやWi-Fi、電力線ネットワーク(PLC)やRFIDを使ったメッシュネットワークなど、複数の方式が 存在して、まだどれかひとつには絞り込まれておらず、しかもそれらの互換性(インターオペラビリティ)の確保については、いままさに作業中といった状態に ある。家庭でのエネルギー管理について、さまざまな陣営がそれぞれ異なるパラダイムを推し進めようとしている。またハードウェア・メーカーにとって、これ はさらにリスクを高めることにつながる。NISTがこの標準策定作業をいかに済ませるかは、来年のスマートグリッド分野における最も大きな問題のひとつに なるだろう。

[著者:Michael Kanellos(Greentech Media)/抄訳:坂和敏/原文公開:11月23日(米国時間)]


原文はこちら:
"The Biggest Thorn for Smart Grid Standards? The Home Area Network"

訳者コメント:
上記ブログではいまひとつ分かりにくい印象ですが、下記の関連記事をみると「なるほどこれは大変そうだ」と思える説明がありました。たとえば、NISTの標準案(ドラフト)はA4サイズで計90ページにもなる代物でそのなかにぎっしりと文字だけが並んでいます。

関連記事:
・"Smart Grid Interoperability Panel: Who to Call"(Greentech Media)

・"Smart Grid Standards Roadmap Unveiled"(Greentech Media)

・"Time short to agree on smart-grid standards" (CNET News.com)

・"NIST Framework and Roadmap for Smart Grid Interoperability Standards Release 1.0 (Draft) "[PDF]


"Royal Society".

創會350年 英皇家學會線上回顧科學史
20091130 14:27:37 小型字 中型字 大型字

(中央社倫敦30日綜合外電報導)英國「倫敦皇家學會」(Royal Society)今天表示,將首度於線上展出珍藏的歷史手稿,部分手稿出自牛頓(Sir Isaac Newton)、富蘭克林(Benjamin Franklin)及其他具開創性發現的科學家之手。

「倫敦皇家學會」是世界上歷史最悠久的科學機構,它將於網站上展出數世紀以來刊載於旗下刊物「英國皇家學會會報」(Philosophical Transactions)的著名文獻,作為350週年慶祝活動之一。

這些文獻包括1666年人類進行首次輸血的血腥紀錄,以及一份1770年代資料,證明莫札特(WolfgangAmadeus Mozart)的確是音樂神童,近期文獻則包括英國科學家霍金(Stephen Hawking)黑洞理論的早期著作。

這個互動性網站名為「開拓」(Trailblazing),將從皇家學會期刊中的6萬篇文章中,選出60則刊載。

皇家學會會長芮斯(Lord Martin Rees)表示:「網站上刊登的科學文獻,代表了科學家數世紀來持續不懈的探索,其中許多人也是皇家學會會員,他們測試並建立人類對自身及宇宙方面的認知。」

「他們個個都代表著科學使我們瞭解更深、看得更遠,令我們為之振奮的時刻。」

牛頓於17世紀發表的光學與色彩原理文獻將被公開,這些理論為後世的理論物理學奠定了研究基礎。美國開國元勳之一富蘭克林1752年的研究報告也是展品之一,他於暴風雨中放風箏實驗,證明閃電是電力,而非超自然現象。

史東(Edward Stone)於1763年發現柳樹皮對發燒的治療功效,紀錄了水楊酸的發現,並促成目前世界最常使用的藥物─阿斯匹林的誕生。

會報中還紀錄了庫克船長(Captain James Cook)在1776年,遠早於營養學發展的年代,如何以酸菜、檸檬和麥芽治療水手的壞血病。

科學家巴林頓(Danies Barrington)同時也是名懷疑主義者,他在莫札特造訪倫敦時,想測試當時8歲的莫札特是否如傳聞般是位天才。巴林頓的紀錄顯示,這名音樂家雖然像普通男孩一樣愛玩、心思不集中,不過也同時展現了過人的天賦。

他寫道:「幾乎是總譜放上桌面的同時,他就能以最熟練的技巧開始演奏交響樂。」

其他文獻還包括最早的種牛痘紀錄。史隆(HansSloane)紀錄了接種過程:「在手臂皮膚製造非常小的切口」置入「紗布,上面滴有成熟無害的天花病毒」。

芮斯表示,皇家學會計畫在未來一年舉辦更多週年慶祝活動,以「激發科學家、家庭、年輕人及感興趣的社會大眾進一步探究科學的面貌。」

皇家學會的正式建立日期,為1660年11月28日。(譯者:中央社戴雅真)981130

Wikipedia article "Royal Society".


The Latin motto of the Royal Society, Nullius in verba, translates as "On the words of no one", or "take nobody's word for it". The full quotation from Horace is Nullius addictus judicare in verba magistri which means "Not compelled to swear to any master's words". This is interpreted by the Society as "an expression of the determination of the Fellows to withstand the domination of authority (such as in Scholasticism) and to verify all statements by an appeal to facts determined by experiment".[5] At its foundation, the philosophical basis of the Royal Society differed from previous philosophies such as Scholasticism, which established scientific truth based on deductive logic, concordance with divine providence and the citation of such ancient authorities as Aristotle. In fact, it represented the final triumph of the vision of the thirteenth-century friar Roger Bacon, who had fought scholastic authorities in an attempt to establish such a repository of learning.



2009年11月26日 星期四

TOP CLIMATE SCIENTISTS SHARE THEIR OUTLOOK


TOP CLIMATE SCIENTISTS SHARE THEIR OUTLOOK


Name: John Mitchell

Age: 61

Nationality: British

Position: Director of Climate Science, Met Office Expertise: Climate modelling

After 36 years at the Met Office, including a spell writing the shipping forecast, John Mitchell has a weather-beaten mind. In person, there is no smug air of foreknowledge. Yet this softly spoken rugby fan from County Down in Northern Ireland is one of the most experienced climate modellers in the world.

Modelling is a contentious area. There's so much we don't fully understand about the climate – clouds, hurricanes, ice melting, aerosols – that questions remain over the ability of super-computers to model future climate. One experiment – Climateprediction.net, which generated thousands of versions of the Met Office's climate model and got people to run them on their home PCs – showed that models will produce radically different results if you make minor adjustments to their parameters. The week before I met Mitchell, the Met Office was forced to defend its “barbecue summer” press release – proving the difficulty of making even seasonal predictions.

Mitchell takes such criticism calmly. “Essentially, a model is based on Newton's Laws of Motion. All we're trying to do with the models is quantify [the warming] better and say what the regional changes are.”

In practice, that means taking balloon and satellite measurements for temperature, winds and humidity in the atmosphere and using equations to give you a rate of change. It is always going to be an approximate picture but he insists there is a “strong resemblance” with what happens in reality.

Big obstacles remain. “There's so much variation out there,” he says, pointing through the window. “How do you model that? Clouds are the ‘Achilles' heel' of modelling.”

But modelling power is increasing all the time. This summer, the government gave people access to detailed regional climate projections for the coming decades. The modelling was done by the Met Office – and though many scientists are uncomfortable with such “postcode predictions”, saying they send out an overconfident message about our understanding of the future, Mitchell is proud that the US is now considering following suit.

Personal stance: Takes small steps – turning down the thermostat and unplugging his mobile phone charger.

姓名:约翰•米切尔(John Mitchell)

年龄:61

国籍:英国

职位:英国气象局(Met Office)气候科学部主任专长:气候模型分析在英国气象局工作了36年之久(其中有一段时间负责编写海上气候预报),约翰•米切尔的头脑已经饱经风霜。外表来看,他丝毫没有拥有先见之明的自负姿态。然而,这个来自北爱尔兰唐郡、语调温和的橄榄球爱好者,却是世界上最有经验的气候模型分析专家之一。

模型分析是一个有争议的领域。关于气候,我们有太多东西都不是很了解——云团、飓风、融冰、悬浮物,因此对于超级计算机模拟未来气候的能力仍然存在 疑问。根据一项试验,Climateprediction.net网站会生成数以千计的气象局气候模型版本,让人们在自己家里的个人电脑上运行。试验结果 显示,如果你对参数进行轻微的调整,模型就会产生截然不同的结果。我与米切尔会面前一周,英国气象局被迫为其“烧烤夏季”(barbecue summer)的新闻稿进行了辩护——这证明哪怕只是进行季节性预测也很困难。

面对这些批评的声音,米切尔表现得很平静。“本质上,模型的基础是牛顿的运动定律。我们所尝试去做的,不过是利用模型(对气候变暖)进行更好的量化,并说明有哪些地区性变化。”

在实践中,这意味着利用气球和卫星测量温度、气流和大气中的湿度,并用方程式得出变化速率。这永远只会是一种大致的描述,但他坚称这与实际情况“非常相似”。

重大障碍依然存在。“那里的变化实在太多了,”他指着窗外说道。“你怎么对它建立模型?云层就是模型分析的致命弱点。”

但模型分析的能力一直在不断增强。今天夏天,英国政府允许人们获取未来数十年详细的地区气候预测信息。这个模型是由英国气象局建立的——尽管许多科 学家不喜欢这种“邮政编码预测”,称它们就我们对未来的了解传递出一种过于自信的信息,但让米切尔感到骄傲的是,美国正在考虑效仿这种做法。

个人立场:从小事做起——调低自动调温器的功率,不充电时从插座上拔掉手机充电器。

译者/管婧

2009年11月25日 星期三

Building an Online Newsstand

Group of Magazine Publishers Is Said to Be Building an Online Newsstand


Published: November 24, 2009

A consortium of magazine publishers including Time Inc. and Condé Nast are plan to jointly build an online newsstand for publications in multiple digital formats, according to people with knowledge of the plans.

The formation of a new company to run the online newsstand — sometimes characterized as an “iTunes for magazines” — may be announced in early December. Time, Condé Nast, Hearst and Meredith all intend to be equity partners in the new company, although the deals have not yet been signed.

In the face of slumping print circulations for many magazines, the publishing houses are eager to exert some control over digital readership, said people at the companies, who spoke on condition of anonymity because they were not authorized to talk about the plans. Some newspaper owners have also expressed interest in the joint venture.

In other media sectors, rivals have already formed joint ventures for the Web. Several television networks are stakeholders in Hulu, an online television and film Web site. Some music labels are partners in Vevo, a music video site powered by YouTube that will make its debut next month.

The new magazine company would, in theory, make it easy to buy print and electronic copies of publications like The New Yorker, Sports Illustrated, Esquire and Better Homes and Gardens from a single Web site. While mostly leaving the hardware to others, the alliance of competing publishers would develop software standards for magazine viewing on iPhones, BlackBerrys, e-book readers and other platforms, people with knowledge of the plans said.

Executives have talked about an iTunes model for magazines for months.

The New York Observer reported Tuesday that John Squires, the Time Inc. executive, would become the new company’s interim chief executive while the partners looked for a permanent head. In June, Ann Moore, the Time Inc. chairwoman, gave Mr. Squires the responsibility of creating a digital road map for the company.

“It’s increasingly clear that finding the right digital business model is crucial for the future of our business,” Ms. Moore said in a memorandum at the time. She added, “We need to develop a strategy for the portable digital world and to refine our views on paid content.” A Time Inc. spokeswoman declined to comment Tuesday.

The magazine industry has been generally slow in experimenting with digital products, but they have shown more interest this year in extending the print experience and audience. This month Condé Nast became one of the first publishers to repurpose an entire magazine issue for the iPhone, selling a copy of GQ as an application for $2.99.

“We know that the world of digital is far grander than display advertising,” Charles H. Townsend, Condé Nast’s chief executive, said at a demonstration of the application last month.

Stephanie Clifford contributed reporting.

2009年11月23日 星期一

半導體儀器的技術

一千億投資到那裡去了?
李家同

我 們都希望有人在台灣投資,愈多投資,愈能帶動經濟。因此,每次我們聽到有人要投資半導體工廠,都會很興奮,因為一家半導體工廠的投資金額總在一千億台幣左 右,試想一千億台幣的投資可以產生多少的工作機會!遺憾的是,半導體工廠雖然投資了一千億,大約九百億卻是要用來買儀器的,這些儀器廠商都是外國的,所以 我們絕大多數的錢是投資到了外國,我們自己國家的工業升級得不到任何好處。

半導體儀器 技術落後

從這件事來看,我們必須承認我們的工業水準其實是不夠厲害的,我們雖然自認為是半導體王國,但是我們卻未能充分掌握半導體儀器的技術,因為儀器是別人的, 我們也就很難發展一種完全屬於我們自己的半導體生產技術。有時,我們會訝異為什麼美國和日本並未像台灣有這麼多半導體工廠?難道他們沒有這種能力嗎?當然 不是,他們掌握住了半導體儀器的技術,就已夠了。這些儀器都極為昂貴,會做這類儀器的廠商又少,他們自然都有高利潤。他們的利潤絕不亞於我們半導體工廠的 利潤,恐怕還要大得多。

半導體儀器乃是非常精密的儀器。我們如果要在一張紙上畫兩條平行線,是很容易的事。如果兩條線間的距離非常小,就很困難了。而積體電路內的線距離都是以奈米為準的,可想而知這種儀器的精密度。我們如果也要能設計半導體儀器,就必須要有設計精密機械的能力。

任何一個國家,想要有高水準的工業,就一定要能設計及製造精密機械。我們一直在強調半導體工業,而半導體工業又需要精密機械,我們就應該將發展半導體儀器列為我們努力的目標。如果我們始終無法自行研發製造半導體所需要的儀器,我們也就無法發展自己的半導體生產技術。

精密機械 穩定度不足

精密機械乃是現代高科技工業所不可缺的工具,如果沒有精密機械,我國的工業不可能脫胎換骨。而我國的半導體工業如此發達,如果我們也有半導體儀器的設計能力,不僅可以將半導體工業帶入更高的境界,也將順勢提高整個國家的機械工業水準。

但是我們必須知道,要推銷這種高性能的工業產品,乃非易事。一架這種產品,賣價可能高達三百萬美金,也就是台幣一億左右。對於任何一家工廠而言,要買一架 新公司的產品,都會猶豫的,這已不是錢的問題,而是這架精密機械的穩定度問題。如果不穩,可能會造成生產線的停擺,而造成極大的損失。

我們已經有這類生產半導體儀器的廠商,政府一方面應該訂定目標,希望在未來,我們可以有完全自製的半導體儀器,更應該集思廣益,發展一種機制,使得我們賣價極高的工業產品,能夠得到世人的信任。我們總不能永遠地將一千億投資到外國去。

(作者為暨南、清華、靜宜大學榮譽教授)

n.Fluent (IBM)

Link by Link

A Translator Tool With a Human Touch


Published: November 22, 2009

HOW hard can it be, as the joke goes, to speak Chinese? (Six-year-olds do it all the time.)

Skip to next paragraph
Ari Fishkind for I.B.M.

David Lubensky, left, and Salim Roukos of I.B.M. are using many humans, namely the company's 400,000 workers, to improve digital translation.

Yes, it turns out that learning languages is one of those skills that humans, even relatively young ones, master seemingly magically. It is all enough to make a mainframe computer jealous.

At I.B.M., a team of nearly 100, including mathematicians and software developers, is working on a project to create an automatic translation tool, so-called machine translation, that has the speed and accuracy to be used in instant-messaging between speakers of two different languages.

The project, called n.Fluent, is intended to teach the computer terminology that is specific to I.B.M.’s businesses, and, more significantly, allow the computer to learn what it has been doing wrong. To that end, the company is extracting and organizing contributions from I.B.M.’s 400,000-member work force spread across more than 170 countries, adding a human touch to the project.

Over a two-week period last month, the company issued a “worldwide translation challenge” to its employees, using a points-based system to award the biggest contributors prizes that were converted to charitable donations. About 6,000 I.B.M. employees made improvements in 11 languages to more than two million words of text translated by n.Fluent.

So, when a machine translation from French produces, “MTTP is the time of 30 minutes and it is steadily declining since January 2006,” a human correction comes up with this improved English version: “The MTTP delay is 30 minutes and it has been steadily declining since January 2006.”

“From this parallel data, we update the models,” said Salim Roukos, an I.B.M. researcher in language-related technology at its T.J. Watson Laboratory in Yorktown Heights, N.Y., home of the n.Fluent project. “You want to learn the idiomatic expressions — when you say someone has kicked the bucket, you don’t want that translated word for word.”

So far, n.Fluent is used only by I.B.M. employees, but the intention is to create a product that can be sold to other businesses.

Efforts like this at I.B.M., as well as social networking tools behind the company’s firewalls, amount to a new twist on “crowdsourcing,” the term I.B.M. officials use to describe them. In addition to the n.Fluent project, I.B.M. has its own companywide version of Wikipedia (Bluepedia), with contributions from 1,300 employees.

Perhaps the most innovative social networking experiment at I.B.M., according to Irene Greif of the I.B.M. Center for Social Software in Cambridge, Mass., is Dogear, a tool similar to Delicious that allows employees to share links and tagging on the Internet as well as on the I.B.M.-only intranet. The project itself was a bit of an experiment, and I.B.M. developers tweaked further, she said.

This led to Dogear, a system of tags and descriptions contributed by 10 percent of users. It has become more popular than I.B.M.’s own internal search engine.

“A small crowd, a self-selected crowd can often be useful,” Ms. Greif said.

This highlights the differences between what is occurring at I.B.M. and other large companies and what traditionally constitutes crowdsourcing.

I.B.M. employees are not just any “crowd”; they have expertise and a loyalty to their employer that any old posse wrangled up on the Internet may not. In fact, crowdsourcing may be the wrong way of thinking of such internal corporate projects. Employee-sourcing?

Maybe that catch-all term “collaboration” is the best way to think of what social networking technology can bring to the workplace.

After all, collaboration is an old goal for employees and employers.

In the case of the n.Fluent project, programmers are not trying to have a computer master the “rules” of a language, but rather are looking for statistical patterns between two sets of translated texts and among the words themselves. For example, Mr. Roukos said, the text of a Canadian parliamentary debate in French and English can help programmers to “build statistical models based on the parallel corpus.”

It is language’s fluidity and unpredictability that thus far make translation resist simple computer-based solutions. Which means that for the foreseeable future, translation experts will also need to become experts on collaboration.

“One of the reasons we’ve got senior-level executives behind this is that it is kind of a Harvard Business School case study of how the crowds inside the company help you develop a better product,” said David Lubensky, another researcher on the n.Fluent project. “We should be able to replicate this over various domains.”

For example, initially, all rewards to contributors were in the form of donations to one of seven worldwide charities. Over time, the team heard that some contributors “would personally want some trinket,” he said. And now small gifts are awarded as well.

Something any 6-year-old could have told you.

US Promotes Math and Science/ democratizing supercomputers

White House Wants to Promote Math and Science
By KENNETH CHANG
The plan will enlist companies and nonprofits, including “Sesame Street,” to spend money and time to encourage students to pursue science, technology, engineering and math.


Shared Supercomputing and Everyday Research
By ASHLEE VANCE
A drop in the price of supercomputers and other advances are pulling down the high walls around computing-intensive research, possibly democratizing the field.

2009年11月22日 星期日

The Large Hadron Collider (LHC)

The Large Hadron Collider (LHC) is the world's largest and highest-energy particle accelerator, intended to collide opposing particle beams of either protons at an energy of 7 TeV per particle or lead nuclei at an energy of 574 TeV per nucleus. It is expected that it will address the most fundamental questions of physics, which seem to block further progress in understanding the deepest laws of nature. The LHC lies in a tunnel 27 kilometres (17 mi) in circumference, as much as 175 metres (570 ft) beneath the Franco-Swiss border near Geneva, Switzerland. It is the world's largest machine.[1]

LHC是在一個圓周為27公里的圓形隧道內,該隧道因當地地形的起伏而位於地下約50至150公尺之間。[1] 這是先前大型電子正子加速器LEP)所使用隧道的再利用。隧道本身直徑三公尺,位於同一平面上,並貫穿瑞士法國邊境,主要的部份大半位於法國。雖然隧道本身位於地底下,尚有許多地面設施如冷卻壓縮機,通風設備,控制電機設備,還有冷凍槽等等建構於其上。

加速器通道中,主要是放置兩個質子束管。由於須維持前所未有高能量的粒子運行,加速管由超導磁鐵所包覆,以液態來冷卻。管中的質子是以相反的方向,環繞著整個環型加速器運行。除此之外,在四個實驗碰撞點附近,另有安裝其他的二極偏向磁鐵及四極聚焦磁鐵

兩個對撞加速管中的質子,初步將以 5 TeV(Tera Electron Volt, 電子伏特)的能量對撞,總撞擊能量達10 TeV之多。(設計目標為14 TeV)每個質子環繞整個儲存環的時間為89 微秒 。因為同步加速器的特性,加速管中的粒子是以粒子團(bunch)的形式,而非連續的粒子流。整個儲存環將會有2800個粒子團,最短碰撞週期為25奈秒 。在加速器開始運作的初期,將會以軌道中放入較少的粒子團的方式運作,碰撞週期為 75 奈秒,再逐步提升到設計目標。

在粒子入射到主加速環之前,會先經過一系列加速設施,逐級提升能量。其中,由兩個直線加速器所構成的質子同步加速器(PS)將產生50 MeV的能量,接著質子同步推進器(PSB)提升能量到1.4GeV。而質子同步加速環可達到26 GeV的能量。低能量入射環(LEIR)為一離子儲存與冷卻的裝置。反物質減速器(AD)可以將3.57 GeV的反質子,減速到2 GeV。最後超級質子同步加速器(SPS)可提升質子的能量到450 GeV。

在LHC加速環的四個碰撞點,分別設有五個偵測器在碰撞點的地穴中。其中超環面儀器ATLAS)與緊湊渺子線圈CMS)是通用型的粒子偵測器。其他三個(LHC底夸克偵測器(LHCb), 大型離子對撞器ALICE)以及全截面彈性散射偵測器TOTEM)則是較小型的特殊目標偵測器。

LHC也可以用來加速對撞 重離子,例如 (Pb)離子因其荷質比(電荷和質量的比值)可加速到1150 TeV。

由於LHC有著對工程技術上極端的挑戰,安全的確保是極其重要的。當LHC開始運作時,磁鐵中的總能量高達100億焦耳(GJ),而粒子束中的總能量也高達725百萬焦耳(MJ)。只需要10−7總粒子能量便可以使超導磁鐵脫離超導態,而丟棄全部加速器中的粒子可相當於一個小型的爆炸。

[編輯] 研究主題

一張描述LHC如何產生希格斯玻色子費曼圖。在圖中,兩個夸克各放射出一個W 及 Z 玻色子,進而融合成一個希格斯玻色子。
在CMS偵測器中希格斯玻色子衰變的模擬事例重建圖。(event display)

物理學家希望藉由加速器對撞機來幫助他們解答下列的問題:

[編輯] 重離子對撞機

雖然LHC的物理實驗計劃,著重於研究質子對撞後的現象。然而,如每年一個月的短期重離子對撞也在實驗計劃之中。雖然其他較輕的離子對撞實驗也是可行的,目前主要的規劃為鉛離子的對撞實驗。[3]

[編輯] LHC升級計劃

有提議在十年內 LHC 需要提昇一次硬體性能。[4] 認為 LHC 需要作基本上硬體的修改以提升它的「亮度」(單位截面碰撞發生的頻率)。理想中 LHC 升級的途徑將是包含增加粒子束的流量,以及修改兩個需要高亮度的區域: ATLAS 與 CMS 這兩個偵測器來配合。下一代超大型強子對撞器的入射能量需增加到 1 TeV,因此前置入射裝置也需升級,特別是「超級質子同步加速器」的部份。

[編輯] 經費支出

LHC的建造經費最初是1995年通過的一筆26億瑞朗, 另有一筆兩億一千萬元瑞朗的經費作為實驗之用。然而,經費超支。在2001年的一次主要審核預期,將需增加四億八千萬元瑞朗在加速器的建造,與五千萬元瑞 朗的支出在實驗運作上。同時,由於CERN年度預算的縮減,LHC的完工日期由2005年延後到2007年四月,以使用更多年度預算來支付。[5] 其中增加的一億八千萬元瑞朗,用於超導磁鐵的製造。另外,尚有在興建放置CMS的地下洞穴時遇到的工程技術上的困難。[6] 預期的建造總額約為八十億元美金

[編輯] LHC@Home

主條目:LHC@home

LHC@Home 是一個 分散式計算 的計劃,用來支持LHC興建與校正之用。這個計劃是使用 BOINC 平台,來模擬粒子如何在加速器隧道中運行。有了這項資訊,科學家便可以決定如何放置磁鐵與調整功率,來達到加速軌道運行的穩定。

[編輯] 安全顧慮

在美國 RHIC 開始實驗之時,包括內部的研究者與其他外部的一些科學家,曾擔心類似的實驗可能會引發理論上的一些災難,甚至摧毀地球或是整個宇宙

RHICCERN 都進行了一些研究調查,檢視是否有可能產生例如微黑洞、微小的奇異物質(奇異微子)或是磁單極等危險的事件。[8]這份報告認為「我們找不到任何可以證實的危害」。例如,除非某個未經證實的理論是對的,否則是不可能產生出微小黑洞的。即使真有微黑洞產生了,預期會透過霍金輻射的 機制,很快就會蒸發消失,所以會是無害的。而像 LHC 這樣高能量的加速器的安全性,最有力的論點在於一個簡單的事實:宇宙射線的能量比起 LHC 來要高出非常多數量級,太陽系星體從形成到現在這麼多年下來,都不斷地被宇宙射線轟擊。既沒有產生出微黑洞、微小的奇異物質或是磁單極,太陽、地球和月球 也都沒有因此被摧毀。

然而,仍有一些人還是對 LHC 的安全性有疑慮:類似這樣新的、未經測試過的實驗,是沒有辦法完全保證上述的情況不會發生。約翰·尼爾森(John Nelson)在伯明罕大學談到RHIC說「這是非常不可能會有危害的──但是我無法百分之百保證。」[9] 另外在學術界,對於霍金輻射是否正確,也有一些疑問。[10]

RHIC 自2000年運行到現在,都沒有產生可以摧毀地球的物質的跡象。

[編輯] 建設意外與延遲

2005年10月25日,因為起重機載貨的意外掉落,造成一位技術人員的喪生。 [11][12]

2007年3月27日,由費米實驗室所 負責建造,一個用於 LHC 內部的三極低溫超導磁鐵(屬於聚焦用四極磁鐵),因為支撐架的設計不良,在壓力測試時發生破損。雖然沒有造成人員的傷亡,但是卻嚴重影響了 LHC 開始運作的時程。費米實驗室主任皮耶·奧登(Pier Oddone)說道:「在這個案例中,我們驚訝地發現到,一個簡單的靜力平衡被疏忽了。」這個錯誤存在原始的設計中,而且經過多年來數次的審核都沒有發 現。[13] 分析發現,為了縮小支撐架的粗細來達成束流管更佳的絕緣效果,卻因此不足以支撐壓力測試時,所施加的外力。詳細的內容可見於費米實驗室的對外說明,CERN 也同意其內容。[14][15] 修復損壞的磁鐵,並且補強八個同型的磁鐵造成了 LHC 預計開始運行的時程,[16] 因此延遲到2007年11月。

2008年9月19日,LHC 第三與第四段之間,冷卻超導磁鐵用的液態氦發生了嚴重的洩漏,佔總量約1/3的高達6噸液態氦洩漏到隧道中。目前據推測是由於費米實驗室負責建造的超導體 磁鐵,在聯接兩個的連接匯流排(bus bar)焊接不良,在超導高電流的情況下產生了熱量使得超導體脫離超導態,電流經過瞬間的高電阻形成了電弧打 穿了冷卻設備的液態氦儲存槽所造成的。依據CERN的安全條例,必需將磁鐵升回到室溫後詳細檢查才能繼續運轉,這將需要三到四週的時間。要再冷卻回運作溫 度,也是得經過三四週的時間,如此即使直接替換掉損壞的元件不進行補強作業,也還是正好遇上預定的年度歲修時程,因此要開始運作將至少可能延遲至2009年春天。[17]

2008年10月16日,CERN發佈了關於液態氦洩漏事件的調查分析,証實了先前推測的為兩超導磁鐵間焊接點不良所造成的。由於安全條例確實地實行、安全設計皆有正常工作、並且替換用的零件都有庫存,依目前CERN於2008年12月5日公佈的時程,LHC將於2009年夏天開始恢復運轉。[18] [19]

根據2009年4月30日 CERN 的最新公報[20],LHC 最後的一段維修偏向磁鐵完成放置回隧道當中,自2008年9月19日洩漏事件以來毀損的磁鐵維修作業終於告一段落。接下來的工作,將專注於完成磁鐵間的連結工作以及預防未來類似洩漏事件的加強監控與補強作業[21]。 在此次的維修作業中,LHC 第三第四段間共有53個磁鐵被替換掉。其中有16個損傷不大的磁鐵,是以良品維修(refurbish)的方式來處理,而另外37個損壞較嚴重的部份,則 是直接由備品替換。這些替換下來的磁鐵,將在維修之後作為將來的備品料件使用。目前 LHC 管理部門所規劃的時程,仍依照2009年2月9日 CERN 所公佈的,將於九月底啟動運轉,並預計十月開始對撞實驗[22]

[編輯] 關聯項目

LHC的緊湊渺子線圈(CMS)偵測器

[編輯] 參考

  1. ^ Symmetry magazine, 2005年四月號
  2. ^ 「......在粒子物理學引發的公開演講中,我們聽到太多關於LHC或是直線加速器(ILC)的目標,都是在於檢視標準模型中,最後一個仍未見著的粒子:希格斯粒子,這個今日的聖盃。事實不應是如此的無趣!我們嘗試提出的,是個更令人感興趣的疑問:我們是否能夠接受一個缺少希格斯機制的世界?這未嘗不是一件令人興奮的事?」-Chris Quigg,Nature's Greatest Puzzles
  3. ^ Ions for LHC
  4. ^ PDF presentation of proposed LHC upgrade
  5. ^ LHC Cost Review to Completion, CERN 2001
  6. ^ Toni Feder.CERN Grapples with LHC Cost Hike.於2006年6月12日查閱.
  7. ^ Dimopoulos, S. and Landsberg, G. Black Holes at the Large Hadron Collider. Phys. Rev. Lett. 87 (2001).
  8. ^ Blaizot, J.-P. et al. Study of Potentially Dangerous Events During Heavy-Ion Collisions at the LHC. (PDF)
  9. ^ Jonathan Leake:Big Bang machine could destroy Earth, Sunday Times
  10. ^ Adam D. Helfer: General Relativity and Quantum Cosmology
  11. ^ http://cosmicvariance.com/2005/10/25/tragedy-at-cern/
  12. ^ http://user.web.cern.ch/user/QuickLinks/Announcements/2005/Accident.html
  13. ^ Fermilab'Dumbfounded'by fiasco that broke magnet
  14. ^ LHC Magnet Test Failure
  15. ^ Updates on LHC inner triplet failure
  16. ^ The God Particle.www.bbc.com.於2007年5月22日查閱.
  17. ^ Incident in LHC section 3-4 (CERN公報).www.cern.ch.於2008年9月20日查閱.
  18. ^ CERN releases analysis of LHC incident (CERN公報).www.cern.ch.於2008年10月16日查閱.
  19. ^ LHC to restart in 2009 (CERN公報).www.cern.ch.於2009年1月28日查閱.
  20. ^ Final LHC magnet goes underground (CERN公報).www.cern.ch.於2009年5月3日查閱.
  21. ^ After Repairs, Summer Start-Up Planned for Collider (紐約時報報導).www.nytimes.com.於2009年5月3日查閱.
  22. ^ CERN management confirms new LHC restart schedule(CERN公報).www.cern.ch.於2009年5月3日查閱.

[編輯] 外部連結

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維基共享資源中相關的多媒體資源:

[編輯] 參考文獻



停機14個月 大型強子對撞器重新啟動
瑞士日內瓦「歐洲核子研究組織」管制中心的科學家,二十日慶祝全球最大粒子加速器「大型強子對撞器」(LHC)重新運轉。(法新社)

〔編譯羅彥傑/綜合二十日外電報導〕歷經十四個月的修復,造價百億美元的全球最大粒子加速器「大型強子對撞器」(LHC),二十日晚間首度恢復運轉,預計明年就會進行首次高能粒子對撞。

全球最大粒子加速器

LHC 坐落在瑞士與法國交界,一個長達二十七公里的環形地下隧道內,以接近絕對零度(攝氏零下二百七十一度)的低溫運作,比外太空還冷。它能使以接近光速運行的 兩束質子束在環形地下隧道的四具偵測器內迎面對撞,偵測撞出來的更小粒子。科學家希望藉此找出理論上存在的「希格斯粒子」,及模擬一百三十七億年前宇宙誕 生的大爆炸後最初情況。

不料去年九月十日首次發射質子束繞行LHC後九天,就因為設備問題導致機件發生一連串損害。瑞士日內瓦的「歐洲核子研究組織」(CERN)耗資四千萬美元修復與改良LHC,以避免重蹈覆轍。

為進行可能自明年一月展開的新科學實驗,CERN逐步推動LHC的重新啟動。發言人吉里斯表示,二十日的LHC重啟作業進展要比預期更快,提早約九小時,首次的質子束繞行是在當地時間晚間十時左右,以順時鐘方向繞行。約兩小時後,科學家讓另一道質子束以相反方向繞行。

微型黑洞帶來世界末日?

吉里斯說,此次重啟乃是LHC邁向科學發現之路的重要里程碑。他強調,LHC一週後將進行低能量相撞,明年進行高能對撞。去年實驗展開前,曾有人擔心將製造出微型黑洞,帶來世界末日。

2009年11月18日 星期三

safer buildings


Spectrum | 17.11.2009 | 19:30

Buildings stand up to the pressure of bombs and Mother Nature

Architects have been designing buildings for years that were solid and practical, but they haven't always reacted well in a crisis. All that could change by simply applying a few new techniques.

Even when bomb explosions do not claim human lives, they are extremely damaging to the buildings in the vicinity of the blast. In Pakistan and Iraq, bombs explosions have, unfortunately, become an almost daily occurrence. Here in Europe researchers are working on two new innovations which can give any building - from banks to embassies - more protection against attacks and natural disasters.

Report: Hellmuth Nordwig/Kate Laycock

German freight trains show severe safety defects

Transportation | 17.11.2009

German freight trains show severe safety defects

Almost one in every five freight trains is travelling through Germany with safety defects, according to a television report. Germany's rail authority has warned operators to improve controls.

The federal railway authority EBA determined in a nationwide check in September that over 18 percent of the trains inspected had "safety-relevant defects" with their wheels or axles, said a television documentary aired on Monday evening on German public television ARD.

Wheels or axles displayed stress marks, dents or corrosion damage, the report said. The wagons should have been unloaded and taken to be repaired. The majority of the some 4,450 wagons tested were owned by Deutsche Bahn subsidiary DB-Schenker.

The documentary said the inspection was the first of its kind since the EBA was founded in 1994. The authority had announced the upcoming check of all freight wagons in Germany following a rail accident in Viareggio, Italy, in June, which killed over 20 people.

Seeking a European solution

EBA head Gerald Hoerster said in a letter to the railways, made available to news agency Reuters, that he assumed "that the necessary measures will be taken on your own authority." This could, for example, be a visual inspection of the axles before departure.

A fireman sprays water on the wrecked car of a freight trainBildunterschrift: Großansicht des Bildes mit der Bildunterschrift: A derailed freight train filled with liquefied natural gas caused an inferno in Viareggio

But the Association of German Transport Companies ( VDV) criticized the EBA for its recommendation. The visual inspection of the axles was not feasible, VDV head Martin Henke said.

"The EBA has not provided evidence of any kind that defects in the paint work or dents in the wagons could lead to accidents," Henke said.

He said the EBA was contradicting itself as it had just certified the sector a "stable level of safety" without serious defects. After all, rail transport was still 44 times safer than trucks, he said.

The association called on the EBA to refrain from going it alone and instead collaborate constructively on a long-term, European solution to safety issues in rail freight traffic.

"The European safety authority has not seen any necessity for short-term measures," Henke said. Together with the European Railway Agency ERA, a task force including railways and relevant authorities are currently developing Europe-wide binding standards for inspecting wheel axles.

"In Germany, over 100,000 foreign wagons are in transit," said Henke. "Therefore, a solely European uniform regulation is appropriate in terms of safety."

Profit instead of safety?

"Rail is the safest means of transport in Germany," Deutsche Bahn's former chief executive Hartmut Mehdorn once said. Never would savings be put ahead of safety, he said. But in fact, Mehdorn, who wanted to go public with Deutsche Bahn, ordered one major rule of thumb: profits. And this occurred at the cost of safety, the documentary said.

hartmut mehdornBildunterschrift: Großansicht des Bildes mit der Bildunterschrift: Mehdorn was pressured to step down in March after a data scandal

The film showed that an accident in 2006 in the Berlin commuter railway system, leaving 35 injured, was caused by weak construction and saving specifications in maintenance. One of the victims from that accident told ARD that this called for criminal proceedings.

"You can't arbitrarily push down costs," said accident victim Ralph H in the report. "It's not about whether the paint is peeling off; this is about ensuring that people get off the train again in good health."

The report concluded that safety supervision did not function well. Operators are currently responsible themselves for secure operations. They inspect their own trains on a voluntary basis.

Hans Juergen Kuehlwetter, a former EBA legal adviser, called for further legal regulations.

"Companies today are under considerable pressure to yield returns," Kuehlwetter said in the report. "This means that inspections of safety-relevant parts are clearly not being undertaken with the intensity they should be."

Deutsche Bahn ignores political demands

Members of the parliament's transport committee told ARD they often felt powerless against Deutsche Bahn. There were no effective controls.

"What bothers me is that, in particular in the Mehdorn era, the impression was given that they couldn't care less about the demands of parliament in this matter," said Patrick Doering of the Free Democratic Party. "Just hand over four billion euros ($5.9 billion) every year, we'll take care of the rest. That is a position which I cannot accept, neither as a parliamentarian nor as a taxpayer."

Dorothee Menzner from the Left party said this attitude angered her.

"It's infuriating that the Deutsche Bahn managers confront us representatives with enormous ignorance and arrogance," Menzner said.

sac/dpa/Reuters/ARD
Editor: Susan Houlton

Fat that actually helps you lose weight

Spectrum | 17.11.2009 | 17:30

Fat that actually helps you lose weight

Scientists hope they can help people lose weight by actually having them put on more fat.

Obesity is a growing problem in many places around the globe. Now some researchers believe a possible solution may be within our reach. They are working on brown fat, a fat that actually burns calories rather than storing them. Studies are at an early stage but offer the intriguing possibility that people could lose weight with the help of the right kind of fat.

Report: Laura Iiyama

2009年11月16日 星期一

The 50 Best Inventions of 2009

Davies and Starr for TIME

At 8:47 a.m. on March 12, fish history happened in Port Lincoln, Australia. A tankful of southern bluefin tuna — regal, predatory fish prized for their buttery sashimi meat — began to spawn, and they didn't stop for more than a month. "People said, 'It can't be done, it can't be done,'" says Hagen Stehr, founder of Clean Seas, the Australian company that operates the breeding facility. "Now we've done it." Scientists believe the breeding population of the highly migratory southern bluefin has probably plummeted more than 90% since the 1950s. Others have gotten Pacific bluefin to spawn and grow in ocean cages, but by coaxing the notoriously fussy southern bluefin to breed in landlocked tanks, Clean Seas may finally have given the future of bluefin aquaculture legs. (Or at least a tail.)


Read more: http://www.time.com/time/specials/packages/article/0,28804,1934027_1934003_1933946,00.html?xid=newsletter-weekly#ixzz0X4Z6bknV


The Best Inventions

  1. The Best Invention of the Year: NASA's Ares Rockets
  2. The Tank-Bred Tuna
  3. The $10 Million Lightbulb
  4. The Smart Thermostat
  5. Controller-Free Gaming
  6. Teleportation
  7. The Telescope for Invisible Stars
  8. The AIDS Vaccine
  9. Tweeting by Thinking
  10. The Electric Eye
  11. The Mercury Probe
  12. The Personal Carbon Footprint
  13. The Solar Shingle
  14. The Handheld Ultrasound
  15. The YikeBike
  16. Vertical Farming
  17. The Planetary Skin
  18. The $20 Knee
  19. A Watchdog for Financial Products
  20. The Electric Microbe
  21. The Bladeless Fan
  22. The Custom Puppy
  23. The Cyborg Beetle
  24. The Biotech Stradivarius
  25. The Nissan Leaf
  26. The Robo-Penguin
  27. The Universal Unicycle
  28. YouTube Funk
  29. Dandelion Rubber
  30. Wooden Bones
  31. The Living Wall
  32. The School of One
  33. The No-Punt Offense
  34. The Human-Powered Vending Machine
  35. The Handyman's X-Ray Vision
  36. Meat Farms
  37. Packing, Improved
  38. The Foldable Speaker
  39. The Levitating Mouse
  40. The Edible Race Car
  41. The High-Speed Helicopter
  42. The Supersuit
  43. The Eyeborg
  44. Spiderweb Silk
  45. The Sky King
  46. The Smart Bullet
  47. The Fashion Robot
  48. The 3-D Camera
  49. The Newest Cloud
  50. The World's Fastest (Steam-Powered) Car

The Five Worst Inventions

  1. The Five Worst Inventions

Poll Results

  1. Poll Results

2009年11月14日 星期六

Water Found on Moon, Researchers Say

Water Found on Moon, Researchers Say

NASA, via Reuters

This artist's rendering released by NASA shows the Lunar Crater Observation and Sensing Satellite as it crashed into the moon to test for the presence of water last month.


Published: November 13, 2009

There is water on the Moon, scientists stated unequivocally on Friday.

“Indeed yes, we found water,” Anthony Colaprete, the principal investigator for NASA’s Lunar Crater Observation and Sensing Satellite, said in a news conference. “And we didn’t find just a little bit. We found a significant amount.”

The confirmation of scientists’ suspicions is welcome news to explorers who might set up home on the lunar surface and to scientists who hope that the water, in the form of ice accumulated over billions of years, holds a record of the solar system’s history.

The satellite, known as Lcross (pronounced L-cross), crashed into a crater near the Moon’s south pole a month ago. The 5,600-miles-per-hour impact carved out a hole 60 to 100 feet wide and kicked up at least 26 gallons of water.

“We got more than just a whiff,” Peter H. Schultz, a professor of geological sciences at Brown University and a co-investigator of the mission, said in a telephone interview. “We practically tasted it with the impact.”

For more than a decade, planetary scientists have seen tantalizing hints of water ice at the bottom of these cold craters where the sun never shines. The Lcross mission, intended to look for water, was made up of two pieces — an empty rocket stage to slam into the floor of Cabeus, a crater 60 miles wide and 2 miles deep, and a small spacecraft to measure what was kicked up.

For space enthusiasts who stayed up, or woke up early, to watch the impact on Oct. 9, the event was anticlimactic, even disappointing, as they failed to see the anticipated debris plume. Even some high-powered telescopes on Earth like the Palomar Observatory in California did not see anything.

The National Aeronautics and Space Administration later said that Lcross did indeed photograph a plume but that the live video stream was not properly attuned to pick out the details.

The water findings came through an analysis of the slight shifts in color after the impact, showing telltale signs of water molecules that had absorbed specific wavelengths of light. “We got good fits,” Dr. Colaprete said. “It was a unique fit.”

The scientists also saw colors of ultraviolet light associated with molecules of hydroxyl, consisting of one hydrogen and one oxygen, presumably water molecules that had been broken apart by the impact and then glowed like neon signs.

In addition, there were squiggles in the data that indicated other molecules, possibly carbon dioxide, sulfur dioxide, methane or more complex carbon-based molecules. “All of those are possibilities,” Dr. Colaprete said, “but we really need to do the work to see which ones work best.”

Remaining in perpetual darkness like other craters near the lunar poles, the bottom of Cabeus is a frigid minus 365 degrees Fahrenheit, cold enough that anything at the bottom of such craters never leaves. These craters are “really like the dusty attic of the solar system,” said Michael Wargo, the chief lunar scientist at NASA headquarters.

The Moon was once thought to be dry. Then came hints of ice in the polar craters. In September, scientists reported an unexpected finding that most of the surface, not just the polar regions, might be covered with a thin veneer of water.

The Lcross scientists said it was not clear how all the different readings of water related to one another, if at all.

The deposits in the lunar craters may be as informative about the Moon as ice cores from Earth’s polar regions are about the planet’s past climates. Scientists want to know the source and history of whatever water they find. It could have come from the impacts of comets, for instance, or from within the Moon.

“Now that we know that water is there, thanks to Lcross, we can begin in earnest to go to this next set of questions,” said Gregory T. Delory of the University of California, Berkeley.

Dr. Delory said the findings of Lcross and other spacecraft were “painting a really surprising new picture of the Moon; rather than a dead and unchanging world, it could be in fact a very dynamic and interesting one.”

Lunar ice, if bountiful, not only gives future settlers something to drink, but could also be broken apart into oxygen and hydrogen. Both are valuable as rocket fuel, and the oxygen would also give astronauts air to breathe.

NASA’s current exploration plans call for a return of astronauts to the Moon by 2020, for the first visit since 1972. But a panel appointed in May recently concluded that trimmings of the agency’s budget made that goal impossible. One option presented to the Obama administration was to bypass Moon landings for now and focus on long-duration missions in deep space.

Even though the signs of water were clear and definitive, the Moon is far from wet. The Cabeus soil could still turn out to be drier than that in deserts on Earth. But Dr. Colaprete also said that he expected that the 26 gallons were a lower limit and that it was too early to estimate the concentration of water in the soil.

2009年11月5日 星期四

「2009星空協奏曲」

親愛的《探索》基礎科學講座觀眾您好:

第二期「2009星空協奏曲」系列講座,前四講已於10月31日告一段落。

您是否錯過了這四場精采的演講呢? 前三場演講已經放置於活動網頁,後續講座影片也將陸續製作完畢,歡迎前往收看! (http://case.ntu.edu.tw/star)

接下來,「2009星空協奏曲」將進入激昂的第二樂章,傳統的世界觀即將受到新學說的挑戰,哥白尼、克卜勒、伽利略、牛頓...多位史上著名的科學家,領導人類進入了科學革命時代...

《探索》講座11月的場次列表為:

11月 7日 - 本週《探索》講座休息一次,歡迎上網收看演講錄影!

11月14日 - 簡單合諧的行星旋律-從哥白尼到克卜勒

11月21日 - 理論實驗的人間協奏-伽利略的落體運動

11月28日 - 古典力學之天地樂曲-牛頓與萬有引力

演講地點均為:台大應用力學研究所演講廳

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