Aristotle believed that the heavens were perfect. If they ever were, they are no longer. The skies above Earth are now littered with the debris (残骸) of dead satellites, bits of old rockets and the odd tool dropped by a spacewalking astronaut. Such is the extent of the detritus that the first accidental collision between two satellites has already taken place. It happened in February 2009, when a defunct (废弃的) Russian Cosmos smashed into a functioning American Iridium, destroying both and creating even more space junk.
To stop this sort of thing happening again Vaios Lappas of the University of Surrey, in England, has designed a system that will remove satellites from orbit at the end of their useful lives--and as a bonus will scour part of the sky clean as it does so. Dr. Lappas’s satellite-removal system employs a solar sail. As light from the sun hits the sail, it imparts a minuscule but continuous acceleration. When a satellite is first launched, the sail is angled in a way that causes this acceleration to keep the satellite in orbit. (Orbits gradually decay as a result of collisions with the small number of air molecules found even at altitudes normally classified as "outer space". )
Solar sails have yet to be used widely to propel spacecraft in this way--several earlier versions came unstuck when the sails failed to unfurl properly-but doing so is not a novel idea in principle The novelty Dr. Lappas envisages is to change the angle of the sail when the satellite has become defunct. Instead of keeping the derelict craft in orbit, it will, over the course of a couple of years, drag it into the atmosphere and thus to a fiery end. Not only that, but the sail will also act like a handkerchief, mopping up microscopic orbital detritus such as flecks of paint from previous launches. A fleck of paint may not sound dangerous, but if travelling at 27 000kph (17 000mph), as it would be in orbit, it could easily penetrate an astronaut’s spacesuit.
A prototype of Dr. Lappas’s design, called CubeSail, will be launched late next year. It weighs just 3kg and, when folded up, measures 30cm (12 inches) by 10era by 10era. Once unfurled, however, the sail will have an area of 25 square metres. If this prototype, which is paid for by EADS, a European aerospace company, proves successful, solar sails might be added to many future satellites. That would enable them to be removed rapidly from orbit when they became useless and would restore to the skies some measure of Aristotelian perfection.
Which one is NOT the application of the system designed by Vaios Lappas

A:To halt creating more space junk. B:To remove the satellites at the end of their useful lives. C:To stop the accidental collisions in space. D:To clean the junk created by dead satellites.

Text 3
Can anyone compete with Microsoft in the world of software applications For years now, Bill Gates & Co. have had clear sailing: the Windows operating system monopoly has helped make their key products--like Word and Outlook--into unbeatable juggernauts. Meanwhile, innovation in those areas proceeds only at the pace that Microsoft deems appropriate.
The Open Source Applications Foundation has a different idea: to promote free software and innovation by creating cool new applications on a bare-bones budget. The not-for-profit OSAF was initially funded with $ 5 million from former Lotus Development Corp. founder Mitch Kapor. For Kapor, this is a fascinating departure. Twenty years ago he introduced one of the first killer applications of the PC age, the Lotus 1-2-3 spreadsheet; it was unabashedly for-profit and was closed-source.
But Kapor always had his heart in the counterculture, and after leaving his company he co-found ed the Electronic Frontier Foundation, a cyber-rights organization. Though he has seen success as an investor, he feels strongly about the open-source movement, which posits that in the age of complex software many people working for nothing can duplicate or even exceed the efforts of the rake-in-the bucks gang. And because the source code is available to all, anyone can improve the product. The continued success of the Linux-powered operating system and Apache Web servers shows that open source is no wild dream, but a serious challenge to the establishment.
Sometime next year the OSAF will begin testing its first product, a personal-information manager that directly takes on Microsoft’s Outlook. Named after the famous mystery novelist, Chandler will run on Mac, Windows and Linux, be loaded with clever features and allow users to share information with others on things like calendar entries. And, of course, it will be free. Kapor has signed up an all-star team, including Lou Montulli (Netscape Navigator browser) and programming legend Andy Hertzfeld. Also participating: thousands of volunteers who believe in the barn-raising spirit of the open-source movement.
Ultimately, Kapor hopes the project will be self-supporting, with money coming from corporate sponsorships, foundations and licensing fees.
For the immediate future, Kapor thinks that Chandler will be simply another alternative in the shadow of the giant. But long term, the OSAF sees a sea change in the industry itself. "If Chandler works, I can’t see why we couldn’t do a word processor or a spreadsheet," says Kapor. After all, he predicts, "in 10 years Office and Windows will be commodities." Meaning that the Open Source Applications Foundation, or anyone else, will be able to plug its products--including an operating sys tem-into your computing world. Microsoft’s will cost money. The others will be free. If Kapor has his way, it’s a long good-bye for Microsoft’s dominance.

The open-source movement is based on the idea that（）

A:counterculture is important. B:everyone can contribute in creating better software. C:experts can improve a software. D:it can be a challenge to the conventions.

Text 2
The World Wide Web has been steadily creating a widespread surge in social capital through E-mail conversations, chat rooms, newsgroups, and e-zones. These ongoing connections are not an underground phenomenon, but a mainstream movement that is rapidly overwhelming traditional business models, according to the authors of another recent book, The Cluetrain Manifesto.
"Our longing for the Web is rooted in the deep resentment we feel towards being managed," writes co-author David Weinberger, a columnist and commentator on the Web’s effect on business. The Cluetrain Manifesto argues that knowledge workers are finding it intolerable that their employers require them to speak in artificial "business voices". The Web has become the ideal alternative: a public place where people can converse in their "authentic voices", outside of an organization’s official communications channel.
Some of the social capital generated by these independent Web conversations is being used by its creators to circumvent the authority of corporations. For example, a car owner who thinks he was overcharged for service to his vehicle posts an inquiry to a newsgroup for people who own the same model of ear. Group members respond with their advice and personal experiences of getting their own cars serviced. The newsgroup is not owned or controlled by the car company. In fact, a mechanic employed by the car company participates in the conversation, offering his knowledge of what charges are reasonable and how company policies vary from dealer to dealer, and even suggesting which dealerships offer the best service.
According to co-author Rick Levine, tile mechanic "was speaking for his company in a new way: honestly, openly, probably without his boss’s explicit sanction." In effect, an employee of the company independently joined a network of consumers to directly help satisfy a customer. "Companies need to harness this sort of caring and let itsviral enthusiasm be communicated in employees’ own voices," writes Levine, former Web Architect for Sun Microsystem’s Java Software group.
As more and more people work online and form Web relationships, shared knowledge could become increasingly personal in cyberspace. Whether business joins in the conversations or not, it seems likely that this fast-growing strain of social capital will remain valuable for those who help to create it.

The word "overwhelming" (Line 3, Paragraph 1 ) probably means（）

A:helping with. B:creating by. C:substituting for. D:arising from.

Text 2 The World Wide Web has been steadily creating a widespread surge in social capital through E-mail conversations, chat rooms, newsgroups, and e-zones. These ongoing connections are not an underground phenomenon, but a mainstream movement that is rapidly overwhelming traditional business models, according to the authors of another recent book, The Cluetrain Manifesto. "Our longing for the Web is rooted in the deep resentment we feel towards being managed," writes co-author David Weinberger, a columnist and commentator on the Web’s effect on business. The Cluetrain Manifesto argues that knowledge workers are finding it intolerable that their employers require them to speak in artificial "business voices". The Web has become the ideal alternative: a public place where people can converse in their "authentic voices", outside of an organization’s official communications channel. Some of the social capital generated by these independent Web conversations is being used by its creators to circumvent the authority of corporations. For example, a car owner who thinks he was overcharged for service to his vehicle posts an inquiry to a newsgroup for people who own the same model of ear. Group members respond with their advice and personal experiences of getting their own cars serviced. The newsgroup is not owned or controlled by the car company. In fact, a mechanic employed by the car company participates in the conversation, offering his knowledge of what charges are reasonable and how company policies vary from dealer to dealer, and even suggesting which dealerships offer the best service. According to co-author Rick Levine, tile mechanic "was speaking for his company in a new way: honestly, openly, probably without his boss’s explicit sanction." In effect, an employee of the company independently joined a network of consumers to directly help satisfy a customer. "Companies need to harness this sort of caring and let itsviral enthusiasm be communicated in employees’ own voices," writes Levine, former Web Architect for Sun Microsystem’s Java Software group. As more and more people work online and form Web relationships, shared knowledge could become increasingly personal in cyberspace. Whether business joins in the conversations or not, it seems likely that this fast-growing strain of social capital will remain valuable for those who help to create it.

The word "overwhelming" (Line 3, Paragraph 1 ) probably means（）

A:helping with. B:creating by. C:substituting for. D:arising from.

Text 3 Can anyone compete with Microsoft in the world of software applications For years now, Bill Gates & Co. have had clear sailing: the Windows operating system monopoly has helped make their key products--like Word and Outlook--into unbeatable juggernauts. Meanwhile, innovation in those areas proceeds only at the pace that Microsoft deems appropriate. The Open Source Applications Foundation has a different idea: to promote free software and innovation by creating cool new applications on a bare-bones budget. The not-for-profit OSAF was initially funded with $ 5 million from former Lotus Development Corp. founder Mitch Kapor. For Kapor, this is a fascinating departure. Twenty years ago he introduced one of the first killer applications of the PC age, the Lotus 1-2-3 spreadsheet; it was unabashedly for-profit and was closed-source. But Kapor always had his heart in the counterculture, and after leaving his company he co-found ed the Electronic Frontier Foundation, a cyber-rights organization. Though he has seen success as an investor, he feels strongly about the open-source movement, which posits that in the age of complex software many people working for nothing can duplicate or even exceed the efforts of the rake-in-the bucks gang. And because the source code is available to all, anyone can improve the product. The continued success of the Linux-powered operating system and Apache Web servers shows that open source is no wild dream, but a serious challenge to the establishment. Sometime next year the OSAF will begin testing its first product, a personal-information manager that directly takes on Microsoft’s Outlook. Named after the famous mystery novelist, Chandler will run on Mac, Windows and Linux, be loaded with clever features and allow users to share information with others on things like calendar entries. And, of course, it will be free. Kapor has signed up an all-star team, including Lou Montulli (Netscape Navigator browser) and programming legend Andy Hertzfeld. Also participating: thousands of volunteers who believe in the barn-raising spirit of the open-source movement. Ultimately, Kapor hopes the project will be self-supporting, with money coming from corporate sponsorships, foundations and licensing fees. For the immediate future, Kapor thinks that Chandler will be simply another alternative in the shadow of the giant. But long term, the OSAF sees a sea change in the industry itself. "If Chandler works, I can’t see why we couldn’t do a word processor or a spreadsheet," says Kapor. After all, he predicts, "in 10 years Office and Windows will be commodities." Meaning that the Open Source Applications Foundation, or anyone else, will be able to plug its products--including an operating sys tem-into your computing world. Microsoft’s will cost money. The others will be free. If Kapor has his way, it’s a long good-bye for Microsoft’s dominance.

The open-source movement is based on the idea that（）

A:counterculture is important. B:everyone can contribute in creating better software. C:experts can improve a software. D:it can be a challenge to the conventions.

For years, researchers have struggled to understand why so many women leave careers inscience and engineering. Theories run the gamut (整个范围), from family-unfriendly work schedules to natural differences between the genders. A new paper by McGill University economist Jennifer Hunt offers another explanation: women leave such jobs when they feel disappointed about pay and the chance of promotion.
Her first finding was that women actually don’t leave jobs in science at an above average rate. The difference, Hunt found, comes from the engineering sector.
That’s not simply because women are exiting the workforce to raise families. About 21% of all graduates surveyed were working in a field unrelated to their highest college degree. That proportion held steady for both men and women. Yet in engineering, there was a gap. About 10% of male engineers were working in an unrelated field, while some 13% of female engineers were. Women who became engineers disproportionately left for other sectors.
The survey suggests options such as working conditions, pay, promotion-opportunities, job location and family-related reasons. As it turned out, more than 60% of the women leaving engineering did so because of dissatisfaction with pay and promotion opportunities. More women than men left engineering for family-related reasons, but that gender gap was no different than what Hunt found in nonengineering professions. "It doesn’t have anything to do with the nature of the work," says Hunt.
The question then becomes why women engineers feel so stifled (窒息) when it comes to pay and promotion. Women also left fields such as financial management and economics at higher than expected rates. The commonality, like engineering, those sectors are male-dominated. Some 74% of financial-management degree holders in the survey sample were male. Men made up 73% of economics graduates. And to take one example from engineering, some 83% of mechanical-engineer grads were male.
Jennifer Hunt concludes that focusing on making engineering jobs more family-friendly alone—by offering flexible work schedules, say—misses an important part of the mark. If we desire to keep women working as engineers, whether for their sakes or society’s, then a better focus may be creating work environments where women feel more able to climb the career ladder.
Which of the suggestions is NOT mentioned to keep women working in engineer

A:Creating better working environment for promotion. B:Making engineering jobs more family-friendly. C:Offering flexible work schedules. D:Calling on the attention from society.

The eight pilot projects funded by $47 million of the Department of Energy’s stimulus money are located in different regions of the country from Hawaii to Massachusetts. The department hopes the projects will uncover which devices or systems work best. But again, the question of success could vary depending on the area and its consumers. In rural towns, smart-grid technology may mean creating a system in which homes and businesses receive electricity without interruption. In windy Colorado, a smart grid may focus more on harnessing wind energy to supplant (取代, 代替) electrical power.
In rural areas, smart-grid technology focuses on

A:creating a system that could be set as an example for all smart grids. B:making use of wind energy to replace electrical power. C:supplying electricity to homes and businesses without interruption. D:the efficiency when transmitting electricity for long distances.