台大外語教學暨資源中心英語學習報

 

Device Turns Stray Microwaves into Energy

把生活周遭的微波轉換成可用能源

Cutaway view inside a cavity magnetron as used in a microwave oven
(more on Wikipedia)

Scientists have built a device they say can capture stray microwave signals and convert them into electrical power capable of recharging a cell phone or other small electronic device.

科學家們設計出將微波訊號轉換成電能的裝置,將可為手機或其他小型的電子設備充電。


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短期課程開放報名資訊

演說與辯論 Speech and Debate (102年11月28日至12月26日 )

由宋智希教授提供密集的演說與辯論訓練課程,同學除了能夠習得口說技巧之外,也能讓你對口說不再感到頭痛,掌握成功的演說與辯論技能,不再害怕英語口說,那麼一定要報名這堂課程,課程絕對可以助你一臂之力。

報名請洽http://homepage.ntu.edu.tw/~avwrite/course/1021w1.html

 

自學包裹中級:75期、中高級:84期

中級:75期

高檔服飾店抵制消費者的退貨欺騙行為

大家是否曾經看過或耳聞有人穿著高檔禮服但是隱約還露出衣服上的標籤,事實上,有些人會去服飾店購買高檔服飾去參加宴會,隔天便會把衣服拿去退貨,換回現金,這樣的行為,其實已經被這些店家注意到了,為了預防這類情形發生,這些衣服上的標籤,被修改成為一個更顯目的標籤,讓消費者無法將標籤輕易給隱藏起來...詳情請參考本期內容喔!

中高級:84期

智慧型手機已經發展到一定的程度了,現在各家科技大廠下一個積極推出的產品就是智慧型手錶了。智慧型手錶最大的好處可以直接穿帶在身上,大幅省下了從包包或口袋拿出來及解鎖的時間。現在我們就來看看相關報導吧。本期自學包裹帶你一探究竟。

快來練習自學包裹吧 | 申請帳號和使用說明

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 E-Freeway主題介紹

feature of the week

Ready: Disaster Master

Ready是一個美國政府為教育民眾具備對於自然與人為災難的應變能力所建立的網站,該網站內容豐富,資訊清楚易懂。雖然我們並非美國人,但急難應對能力是不分國界的,了解不同的威脅不僅幫助自己,也幫助週遭的家人、朋友或陌生人,當然在這邊,還可以學習英文,真是一舉數得!

來看介紹 | 直接進入網站


Members Only資源介紹

LiveABC: CNN

CNN新聞是相當好的英語學習資源,但是在看新聞時常常會覺得鴨子聽雷,或是說話速度太快,讓人措手不及。現在藉由LiveABC的練習題與英文腳本的幫助,讓你反覆聆聽英語新聞,不知不覺中輕鬆地聽懂英語新聞。...... 來看看該如何使用吧!


Listening for specific information: BBC Skillswise

這個網站用電話留言與電影資訊等日常生活常見的情境為例,教你如何從中聽中重要的訊息,除了完整的一套課程,還有小遊戲!

http://efreeway.avcenter.ntu.edu.tw/freeway/listening/listening_ls.htm#lsi

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 館藏介紹

Successful Presentations teaches students the skills they need for effective and confident communication in presentations in English. Successful Presentations guides the student step-by-step towards creating and delivering a successful presentation, from planning to conclusion.


 英語宅急便     

Device Turns Stray Microwaves into Energy

VOA News

November 12, 2013

Scientists have built a device they say can capture stray microwave signals and convert them into electrical power capable of recharging a cell phone or other small electronic device.

Researchers at Duke University’s Pratt School of Engineering in North Carolina say the device is similar to a solar panel and has a similar efficiency, and while it harvests microwaves, the researchers think the harvester could be tuned to harvest the signal from other energy sources, including satellite signals, sound signals or Wi-Fi signals.

The harvester uses something called “metamaterials,” which are “engineered structures that can capture various forms of wave energy and tune them for useful applications.”

“Until now, a lot of work with metamaterials has been theoretical,” said graduate student Alexander Katko. “We are showing that with a little work, these materials can be useful for consumer applications.”

Researchers used a series of five fiberglass and copper energy conductors wired together on a circuit board to convert microwaves into 7.3V of electricity. By comparison, Universal Serial Bus (USB) chargers for small electronic devices provide about 5V.

“We were aiming for the highest energy efficiency we could achieve,” said engineering student Allen Hawkes. “We had been getting energy efficiency around 6 to 10 percent, but with this design we were able to dramatically improve energy conversion to 37 percent, which is comparable to what is achieved in solar cells.”

With additional modifications, the researchers said the power-harvesting metamaterial could potentially be built into a cell phone, allowing the phone to recharge wirelessly while not in use. This feature could, in principle, allow people living in locations without ready access to a conventional power outlet to harvest energy from a nearby cell phone tower instead.

“Our work demonstrates a simple and inexpensive approach to electromagnetic power harvesting,” said lead investigator Steven Cummer.“The beauty of the design is that the basic building blocks are self-contained and additive. One can simply assemble more blocks to increase the scavenged power.”

The Duke study appears in the journal Applied Physics Letters in December 2013.


Language Notes

stray (a) 流散的,漫步的

convert (v) 轉換;轉變XXXXX*後接 intoconvert . . . into . . .

harvest (v) 獲得,得到

tune (v) 調整 . . . 的頻率;使協調XXXXX*tune做這個用法時,可以加上 fine 成為複合字:fine-tune,表示「微調」

科學家們製作了把空間中散佈的 (stray) 微波訊號 (microwave signals) 轉換 (convert . . . into . . .) 成電能的裝置,可以替手機或其他小型的電子裝置充電。杜克大學 (Duke University) 的研究人員表示,這個裝置跟太陽能板 (solar panel) 一樣,也有差不多的轉換效率 (efficiency),除了收集微波之外,經過調整 (tune) 後,也能收集其他能量源,像是衛星、聲音,或是Wi-Fi的訊號。

這個收集器使用所謂的「超材料」(metamaterials),透過特殊設計後的構造,可以捕捉多種形式的波能量 (wave energy),再經過調整後能被有效運用 (applications)。

theoretical (a) 理論的;非應用的

conductor (n) 導體

comparable (a) 比得上XXXXX *後接 to

研究人員把一列五個材質為玻璃纖維 (fiberglass) 與銅的能量傳導體 (conductor) 接線到電路板上 (circuit board),成功將微波轉換成 7.3 福特的電力;比較起來 (by comparison),USB充電座給小型電子裝置提供的電力約是5福特。參與設計的學生說:「之前能源轉換的效率大概是 6~10%,但現在的設計可以大幅度 (dramatically) 提升能源轉換率 (energy conversion) 到37%,這樣就比得上 (comparable to) 太陽能電板了。」

in principle (phr) 原則上;大體上

power outlet (n) 插座

self-contained (a) 整套的完備的

scavenge (v) 從垃圾中收集(有用物品)

研究人員認為,這個收集能量的超物質經過些改造後,可以內建於 (be built into ) 手機,沒有在使用手機時能將無線充電 (recharge wirelessly)。這樣特別的功能,原則上 (in principle) 還可以讓居住地點無法取得一般電力座供電的人,透過附近的 (nearby) 手機基地台 (cell phone tower) 來汲取電力。

研究主持人 (lead investigator) 表示,這個設計的優點在於每個基本的構成方塊都是各自獨立的 (self-contained)、可增添的 (additive),只要將更多的方塊組裝一起 (assemble) 就能增加收集來的 (scavenged) 電力。


Check your vocabulary!

Fill in the blanks with a word or phrase from the list above. Make necessary changes. After you finish, select the text below to reveal the hidden answers.

1. There are people who live in the dump and scavenge garbage for a living.

2. They converted the spare bedroom into an office.

3. The size of a dolphin's brain is comparable to a human's.

4. In principle, the new software should make the accounting system a lot simpler.

5. If the engine needs to be tuned, Dad can do it.


Source:http://www.voanews.com/content/device-turns-stray-microwaves-into-energy/1788608.html

編譯:簡嘉呈

 
 
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