22 апреля 2009 | Автор: Admin | Рубрика: Скачать журналы бесплатно » Научные журналы | Комментариев: 0
Science, September 12, 2008
PDF | English | 27.1 MB
Millions of books written before the computer era are being digitized for preservation. Because the ink has faded, optical character recognition software cannot decipher many words. Through a repurposing of an existing online security technology called CAPTCHA, these words are being manually transcribed by millions of Web users.
The Mushroom Cloud's Silver Lining
Fallout from atomic bomb testing is helping to solve crimes and address some of the most controversial questions in biology.
Obama and McCain Are Swept Up in a Surprising Space Race
Space policy may not be on the minds of most Americans, but it's become an important issue in the race for the White House. How did that happen, and what does it mean for President Bush's 2004 vision for exploration?
The Houbara: Headed for Oblivion?
The elusive Asian houbara bustard could fall victim to falconers and poaching without strong international protection.
Enhanced Sensitivity of Photodetection via Quantum Illumination
Quantum-mechanically entangled light, in which one photon is kept as a reference, can exponentially improve the imaging of an object, as compared with unentangled illumination.
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