Immensely useful article for learning about Linux kernel at IBM DeveloperWorks.
A LED is a unique type of semiconductor diode. Like a normal diode, it consists of a chip of semiconducting material impregnated, or doped, with impurities to create a p-n junction. As in other diodes, current flows easily from the p-side, or anode, to the n-side, or cathode, but not in the reverse direction. Charge-carriers - electrons and electron holes - flow into the junction from electrodes with different voltages. When an electron meets a hole, it falls into a lower energy level, and releases energy in the form of a photon.
The wavelength of the light emitted, and therefore its color, depends on the band gap energy of the materials forming the p-n junction. In silicon or germanium diodes, the electrons and holes recombine by a non-radiative transition which produces no optical emission, because these are indirect bandgap materials. The materials used for an LED have a direct band gap with energies corresponding to near-infrared, visible or near-ultraviolet light. Free standing LEDs are usually constantly illuminated when a current passes through them, but flashing LEDs are also available. Flashing LEDs resemble standard LEDs but they contain a small chip inside which causes the LED to flash with a typical period of one second. This type of LED comes most commonly as red, yellow, or green. Most flashing LEDs emit light of a single wavelength, but multicolored flashing LEDs are available too.
Php Object Generator, (POG) is an open source PHP code generator which automatically generates clean & tested Object Oriented code for PHP4/PHP5 application to access the underlying database. By generating PHP objects with integrated CRUD methods, POG gives you a head start in any project and saves you from writing and testing SQL queries. The time you save can be spent on more interesting areas of your project. Give it a try!
MyDBO is a powerful object-oriented code generator for PHP/MySQL Web application developers. It is designed to remove the hassle of implementing familiar database operations (select, update, insert, etc) over and over again when creating Web applications. It creates code for accessing your database tables without you having to worry about connections or SQL queries. It also allows you to approach your database in an object-oriented fashion, thus giving you real flexibility. It uses templates to generate code, so it is also possible to create your own templates.
The OpenCD project aims to introduce users of MS-Windows to the benefits of Free and Open Source Software (FOSS).
When you insert the disc into your computer it automatically launches a browser which will guide you through the contents of the disc, presenting the various programs, and allow you to easily install them. The programs are carefully selected to ensure stability, ease of use and a clean install and un-install from your computer. This CD is intended as a first introduction to the world of OSS, in the hope that you will later go on to explore other projects, and at some stage you may even want to try a whole new operating system such as Linux.
The latest edition also lets you boot into a highly polished desktop based on Ubuntu for a taste of the world of free operating systems! Many of the same applications found on the Windows side of the disc are also pre-installed on the live Ubuntu demo, showing how the user experience and data can be preserved across platforms.
SOFIA initiative is to support and advance education by making high-quality content freely available on the Web for learners and faculty across the nation and the world. Modeled after MIT’s OpenCourseWare Initiative, the Sofia initiative encourages the publication and free exchange of community college-level course materials on the World Wide Web.
Check out the course gallery for some excellent study material.