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What is Arduino?

Arduino is a tool for making computers that can sense and control more of the physical world than your desktop computer. It's an open-source physical computing platform based on a simple microcontroller board, and a development environment for writing software for the board.

Inexpensive - Arduino boards are relatively inexpensive compared to other microcontroller platforms. The least expensive version of the Arduino module can be assembled by hand, and even the pre-assembled Arduino modules cost less than $50

Light-emitting diode

A light-emitting diode (LED) is a semiconductor light source.[3] LEDs are used as indicator lamps in many devices and are increasingly used for other lighting. Introduced as a practical electronic component in 1962,[4] early LEDs emitted low-intensity red light, but modern versions are available across the visible, ultraviolet, and infrared wavelengths, with very high brightness. When a light-emitting diode is forward-biased (switched on), electrons are able to recombine with electron holes within the device, releasing energy in the form of photons. This effect is called electroluminescence and the color of the light (corresponding to the energy of the photon) is determined by the energy gap of the semiconductor. LEDs are often small in area (less than 1 mm2), and integrated optical components may be used to shape its radiation pattern.[5] LEDs present many advantages over incandescent light sources including lower energy consumption, longer lifetime, improved robustness, smaller size, and faster switching. LEDs powerful enough for room lighting are relatively expensive and require more precise current and heat management than compact fluorescent lamp sources of comparable output. Light-emitting diodes are used in applications as diverse as aviation lighting, automotive lighting, advertising, general lighting, and traffic signals. LEDs have allowed new text, video displays, live video, and sensors to be developed, while their high switching rates are also useful in advanced communications technology. Infrared LEDs are also used in the remote control units of many commercial products including televisions, DVD players, and other domestic appliances.

open-source social networking project Diaspora

if the team is half as good at building software as it is at building hype, there might be something interesting in the upcoming release, and maybe even a viable business.

The big challenge is that the enterprise developer world isn't screaming out for an open-source Facebook, nor are consumers really looking to run their own instances of social networks. What they really want is for Facebook to take privacy more seriously

DASH7 is an open source wireless sensor networking standard for wireless sensor networking, which operates in the 433 MHz unlicensed ISM band. DASH7 provides multi-year battery life, range of up to 2 km, indoor location with 1 meter accuracy, low latency for connecting with moving things, a very small open source protocol stack, AES 128-bit public key encryption support, and data transfer of up to 200 kbit/s. DASH7 is the name of the technology promoted by the non-profit consortium called the DASH7 Alliance.

The 620325 Stirling Engine by Thames and Kosmos uses renewable energy from the sun to drive a generator, which charges a rechargeable battery to power an electric car.

Power a Car with Solar Generated Electricity       Discover the Stirling engine, a simple, clean and efficient energy technology that is quickly becoming a viable source of electricity as the availability of fossil fuels declines. The Stirling engine in this kit uses renewable energy from the sun to drive a generator, which charges a rechargeable battery to power an electric car. Named after its inventor, Robert Stirling, the original Stirling engine dates back almost 200 years. Today, high-tech Stirling engines are being used in arrays of giant mirrored solar collectors and common applications like compact generators. NASA is even working on using Stirling engines to power a human outpost on the moon!Like a steam engine, a Stirling engine is a heat engine that converts heat energy into mechanical work, usually to drive a generator that then converts the mechanical energy into electricity. But instead of water and steam, the Stirling engine uses a permanently enclosed volume of gas, such as air or helium, to perform the mechanical work. Stirling engines are highly efficient, can operate very quietly, and can use many different sources of heat: combustion of fuels, nuclear fission, geothermal, or solar heat, as this model uses. The Stirling engine in this kit is located in acharging station with a mirrored parabolic dish. The dish focuses the sun’s rays onto the cylindrical glass bulb of the Stirling engine to heat it up. The air inside the bulb heats up and pushes a piston, which turns an electric generator. The generator produces electricity that charges a rechargeable battery in the car. The car runs on an electric motor powered by the battery.The kit includes the charging station with a beta type Stirling engine, the electric car, and a full-color, 64-page manual.

CrazyFlie flight video

The copter itself is organised around the main CPU. The job of this CPU is to acquire the physical measurement given by the gyroscopes and accelerometers and to control the motors to keep the copter stable. This is done by a regulation loop which controls the motors speed 250 times per second. The radio communication has a pretty low bandwidth and is used to send commands to the copter and receive telemetry data from it. The CPU program can be updated by radio.

The computer runs control and telemetry programs. The control program reads the input from a game-pad and sends control commands to the copter. We also have programs that can configure the copter regulation parameters and log the measurements in order to make easier to tune the regulation. All the development is done on Windows and Linux. Indeed we are 3 to work on this project, two of us work on Linux and one is mainly on Windows. Using FLOSS permit to handle that in a very effective way. We are mainly using the GCC compiler from CodeSourcery for the copter program compilation, GNU Make for the project build, Mercurial for the source control, and python/pyusb for the communication with the copter. All these softwares works seamlessly on both Linux and Windows and made the project pretty easy to handle. The distance between the motors (horizontally and vertically) is around 8 cm and the total weight is around 20 g.

What is Scrapy? Scrapy is a fast high-level screen scraping and web crawling framework, used to crawl websites and extract structured data from their pages. It can be used for a wide range of purposes, from data mining to monitoring and automated testing.

A particle carrying a charge of 1 coulomb and passing through a magnetic field of 1 tesla at a speed of 1 meter per second perpendicular to said field experiences a force of 1 newton, according to the Lorentz force law. As an SI derived unit, the tesla can also be expressed as (in SI base units).[3] Units used: A = ampere C = coulomb kg = kilogram m = meter N = newton s = second T = tesla V = volt Wb = weber [edit] Electric vs Magnetic Field

The difference between magnetic field strength (in tesla) vs electric field strength can be confusing.[citation needed] The difference is that a force of magnetic field on a charged particle is generally due to the charged particle's movement[4] while the force imparted by an electric field on a charged particle is not due to the charged particle's movement. This can be seen by looking at the units for each. Electric field is N/C, while magnetic field (in tesla) can be written as N/(C*m/s). The difference between the two is m/s, or velocity. This can further be seen by noting that whether a field is magnetic or electric is dependent on one's relativistic reference frame (that is: one's velocity relative to the field).[5][6] In ferromagnets the movement creating the magnetic field is the electron spin[7] (and to a lesser extent electron orbital angular momentum). In current carrying wire (electromagnets) the movement is due to electrons moving through the wire (whether the wire's straight or circular).

WeTab presents the first tablet with open operating system MeeGo

Working intensively with Intel, we have developed the WeTab OS with MeeGo to meet the requirements of a tablet user in the best way possible. The tablet runs extremely fast

The Web-browser plays a special role here and is based on the free HTML rendering engine WebKit, enabling fast and unrestricted surfing enjoyment including HTML5, Adobe Flash® and Java™.

SIP Communicator - the Java VoIP and Instant Messaging client.

SIP Communicator is an audio/video Internet phone and instant messenger that supports some of the most popular VoIP and instant messaging protocols such as SIP, Jabber, AIM/ICQ, MSN, Yahoo! Messenger, Bonjour, IRC and a whole lot of other useful features.

SIP Communicator is completely Open Source / Free Software, and is freely available under the terms of the GNU Lesser General Public License.

Energy Sources

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Qu'est-ce que PHP? PHP est un langage interprété (un langage de script) exécuté du côté serveur (comme les scripts CGI, ASP, ...) et non du côté client (un script écrit en Javascript ou une applet Java s'exécute sur votre ordinateur...). La syntaxe du langage provient de celles du langage C, du Perl et de Java. Ses principaux atouts sont : Une grande communauté de développeurs partageant des centaines de milliers d'exemples de script PHP ; La gratuité et la disponibilité du code source (PHP est distribué sous licence GNU GPL) ; La simplicité d'écriture de scripts ; La possibilité d'inclure le script PHP au sein d'une page HTML (contrairement aux scripts CGi, pour lesquels il faut écrire des lignes de code pour afficher chaque ligne en langage HTML) ; La simplicité d'interfaçage avec des bases de données (de nombreux SGBD sont supportés, mais le plus utilisé avec ce langage est MySQL, un SGBD gratuit disponible sur de nombreuses plateformes : Unix, Linux, Windows, MacOs X, Solaris, etc...) ; L'intégration au sein de nombreux serveurs web (Apache, Microsoft IIS, etc.).

Origines de PHP Le langage PHP a été mis au point au début d'automne 1994 par Rasmus Lerdorf. Ce langage de script lui permettait de conserver la trace des utilisateurs venant consulter son CV sur son site, grâce à l'accès à une base de données par l'intermédiaire de requêtes SQL. Ainsi, étant donné que de nombreux internautes lui demandèrent ce programme, Rasmus Lerdorf mit en ligne en 1995 la première version de ce programme qu'il baptisa Personal Sommaire Page Tools, puis Personal Home Page v1.0