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Un tee-shirt (Quartermane/Flickr) L’universitaire américain Paul Duguid, spécialiste des médias, a travaillé sur Wikipédia. Il évoque le modèle de savoir démocratique de l’encyclopédie en ligne et ses limites. « La “connaissance” est un bien que nous acquérons par un engagement plus actif », estime-t-il. Professeur à l’université de Californie à Berkeley, a écrit avec John Seely Brown, de Xerox, « The Social Life of Information » (« La vie sociale de l’information »), Harvard Business Press, 2000. Il a publié une étude sur Wikipédia et les limites de l’auto-organisation dans la revue en ligne First Monday.
MIT Understanding Lasers and Fiberoptics full course by MIT Lasers are essential to an incredibly large number of applications. Today, they are used in bar code readers, compact discs, medicine, communications, sensors, materials processing, computer printers, data processing, 3D-imaging, spectroscopy, navigation, non-destructive testing, chemical processing, color copiers, laser "shows", and in the military.
In a life-or-death situation, human beings are capable of incredible feats of bravery and self-control . One of the most remarkable ever recorded was that of Leonid Rogozov, the medic at a Soviet Antarctic research station who was forced to remove his own appendix. I write about the incident at some length in ; to my delight, I've discovered that Rogozov's son has recently published a paper providing even more details on the case. The more I learn, the more incredible it seems. During the late ‘50s and early ‘60s, the Cold War took on new and more literal meaning as the United States and Russia expanded their rivalry into the heart of Antarctica.
This image is the farthest humanity has peered into the universe. We now know that the universe is much larger than previously thought. A much more in-depth explanation of the science behind the video can be found at Deep Astronomy Movies, wallpapers, info on our universe, and information on the James Webb Space Telescope, NASA's next orbiting observatory can be found at NASA's Hubble site Another site you may enjoy, if you enjoyed this video is Hubble Heritage Gallery