Jac Londe's List: Science

• Thinking about solar?
• Green Ray Solar this week is expected to announce UL certification for a solar panel that puts out alternating current, rather than direct current as most solar photovoltaic panels do today. AC panels can be simpler to install and wire together than traditional panels, which makes a piecemeal approach easier,
• Traditionally, solar panels are tied into a device called an inverter, which converts the direct current from panels into household alternating current. Strung together, several panels produce enough voltage to run an inverter which, sized for a rooftop array, is roughly as big as a computer monitor.
• A microinverter brings that DC-to-AC function onto each individual panel. Proponents say the technology simplifies installation and improves panel performance.
• For example, shading on one panel will not affect the output of other panels connected to it, as happens with panels connected to a centralized inverter.

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• Web of Science
• Web of Science  ® provides researchers, administrators, faculty, and students with quick, powerful access to the world's leading citation databases.  Authoritative, multidisciplinary content covers over 10,000 of the highest impact journals worldwide, including Open Access journals and over 110,000 conference proceedings.  You'll find current and retrospective coverage in the sciences, social sciences, arts, and humanities, with coverage available to 1900.

• Pentax Optio W90
• $279.99
• • 12.1 megapixel, 720p HD video
  • Rugged, Waterproof, Shockproof, Coldproof
  • Microscope mode with 3 LED light
  • 5X wide optical zoom
  • 1 year warranty
• Overview

   

         

   The rugged Optio W90 offers enhanced waterproof, shockproof, dustproof, and coldproof performance and has a number of advanced, user-friendly features including a 12.1 megapixel high resolution CCD sensor, internal 5X optical zoom lens, large 2.7 inch LCD and HDTV-proportioned movie recording. An inventive Digital Microscope mode with LED lighting perfectly captures even the smallest and closest macro subjects as near as 1cm from the camera. Ideal for shooting in almost any condition, the Optio W90 is the perfect companion for all your outdoor adventures.

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• Nombre figuré
• un nombre entier qui peut être représenté par un ensemble de points disposés de façon plus ou moins régulière et formant une figure géométrique.
• On attribue parfois à Pythagore les premières études de nombres figurés^[1] (nombres carrés). Diophante a résolu plusieurs problèmes les concernant. Pascal a écrit un traité sur le sujet.

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• Cairn.info
• est né de la volonté de quatre maisons d'édition (Belin, De Boeck, La Découverte et Erès) ayant en charge la publication et la diffusion de revues de sciences humaines et sociales, d’unir leurs efforts pour améliorer leur présence sur l’Internet, et de proposer à d’autres acteurs souhaitant développer une version électronique de leurs publications, les outils techniques et commerciaux développés à cet effet.

• Mini-bots
• map out building interiors

• The rolling droids are being developed by Georgia Institute of Technology, the University of Pennsylvania, and the California Institute of Technology/Jet Propulsion Laboratory (JPL). Equipped with two cameras and laser scanners, they can autonomously explore hallways in an unfamiliar building, detecting doors and windows, and create a map for users such as soldiers or firefighters.

   The project is part of the Micro Autonomous Systems and Technology (MAST) program and is being sponsored by the Army Research Laboratory. The program is aimed at developing palm-size machines that can hover in place, enter buildings, and perform other insect-like stunts while gathering data and relaying it to human controllers.

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