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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.

Share Your Sounds Capture a voice, moment or music in seconds or upload audio you’ve already created. Everyone has sounds to share.Now you can share yours.

Le LTE (Long Term Evolution) est l'évolution la plus récente des normes de téléphonie mobile : GSM/EDGE, UMTS, CDMA2000 et TD-SCDMA.

La largeur de la bande de fréquences allouée à l’opérateur du réseau. Le débit utile est pratiquement proportionnel à cette largeur de bande (pouvant varier de 1,4 MHz à 20 MHz en LTE, 100 MHz en LTE Advanced).

Les types d’antennes utilisés coté terminal et coté réseau (antenne relais): le débit binaire maximal de 326,4 Mbit/s suppose des antennes MIMO 4X4 (quadruples) aux 2 extrémités de la liaison radio LTE (cas de figure peu réaliste pour un téléphone mobile ou un smartphone). La distance entre le terminal et la (ou les) antennes fixes (le débit est très inférieur en périphérie de cellules radio à cause des interférences avec les cellules adjacentes) et les conditions de réception radio (interférences, bruit, échos liés aux réflexions sur les immeubles, …). Le nombre d’utilisateurs actifs se partageant la bande passante au sein d’une cellule (surface radiante d'une antenne) LTE; plus il y a d’abonnés en communication moins chacun a de débit unitaire. La position fixe (statique) ou « en mouvement » du terminal de l’abonné ; le débit utile est réduit pour un terminal en mouvement. La capacité en débit et en nombre d'utilisateurs simultanés de la station de base (eNode B) et le débit du lien optique reliant cette station au cœur de réseau. Le type et la catégorie du terminal influent aussi sur le débit maximum possible ; par exemple un terminal LTE (en anglais : UE "User Equipment") de catégorie 1, ne supporte qu’un débit binaire de 10 Mbit/s alors qu’un autre de catégorie 3 supportera 100 Mbit/s (voir tableau ci-dessous). En contrepartie, plus la catégorie du terminal est élevée, plus le terminal sera complexe (coûteux) et moins son autonomie sera grande (à niveau technologique égal).

by Philip J. Corso

Contents Forward Introduction Chapter 01 - The Roswell Desert Chapter 02 - Convoy to Fort Riley Chapter 03 - The Roswell Artifacts Chapter 04 - Inside the Pentagon at the Foreign Technology Desk Chapter 05 - The Cover-up Chapter 06 - The Strategy Chapter 07 - The EBE Chapter 08 - The Project Gets Under Way Chapter 09 - The Project Had Officially Begun Chapter 10 - The U2 Program and Project Corona - Spies in Space Chapter 11 - Project Moon Base Chapter 12 - The Integrated Circuit Chip - From the Roswell Crash Site to Silicon Valley Chapter 13 - The Laser Chapter 14 - The Antimissile Missile Project Chapter 15 - My Last Year in R&D - The Hoover Files, Fiber Optics, Supertenacity, and Other Artifacts Chapter 16 - 'Tesla’s Death Ray' and the Accelerated Particle Beam Weapon Chapter 17 - Star Wars Afterword

Système d'opération : Androïde 4.0 ICS de GoogleConnexion internet de Wi-FiHDMI dehors 1080PAppui de l'instantané 11 d'AdobeCortex A5 Processor+Mali400 GPU de Telechips TCC8923 1.0GHzMarché androïde, milliers d'apps disponiblesContrôleur/infra à télécommande à distanceYouTube, Hulu, radio d'Internet, jeu visuel en ligne etc. Facebook, Twitter, Picasa, clignotement, gestion de réseau de Social de Google+ etc. Gmail, lecteur de pdf, bureau de lecteur d'e-Livre à allerSoutient la langue multi : Arabe, anglais, français, italien, allemand, espagnol, portugais, grec, hollandais, danois,Le Russe, polonais, Norvégien, Suédois, Tchèque, turc, a simplifié/chinois traditionnel, Coréen, et Japonais

Star I9220 Note 5 inch Phone Tablet Android 4.0 ICS MTK6575 Cortex A9 Dual SIM Dual Camera 5MP WiFi GPS Bluetooth

Processor   CPU GPU Operating System Memory ROM ARM Cortex A9, 1GHz CPU Mali™-400MP Graphics Processing Unit Android 2.3 Gingerbread. Will be updated later to Android 4.0 ICS 512MB (optional 256MB) Built-in 4GB NAND Flash Interfaces   Networking USB Power SD HDMI Built in WiFi module 802.11b/g/n 10/100Mbps with internal antenna USB 2.0 HOST port Mini USB port for power supply (1A required) Micro SD card slot, support up to 32GB HDMI 1.3 OUTPUT (Video and Audio)

ndroid 4.0 Mini PC MK802 RAM 512MB ROM 4G mini TV BoxAndroid 4.0 Mini PC MK802 Features:-This is the smallest Android TV player in the world,it looks like a USB flash drive, twice as big as a USB stick,but compared to a regular small Android TV box,the size is only 25%. You can attach it to the back of your TV, easy to hide. -It outputs the video to TV via HDMI, a short HDMI cable is included, it requires your TV to have a HDMI input. -It is powered by a USB cable, this USB cable is included, but you need to purchase a compatible USB adapter (5V,2A),we can also give it to you if you tell me which country you are from, we will know what kind of USB adapter you need. -It has a regular USB port, you can connect your USB mouse or keyboard here, you can also connect a 2.4GHz wireless mouse and keyboard dongle here,please be noted that mouse and keyboard are not included. -It also has a micro USB port which can be used to connected to your PC. You can use it to copy files from your PC to this little guy. -It also has a micro TF card slot, you can insert a micro TF card with up to 32GB of movie or pictures here. -It doesnt have an ethernet port, you need to use WIFI to connect it to the internet. -It also no RGB port,no S-video port, no built-in IR,no built-in bluetooth. Are you still not clear ?-Connect this (mini CPU) to a monitor and a mouse (Fly mouse or USB mouse). -Switch ON both monitor and this player. -You’re ready to run Android 4.0 OS. -No other thing is needed. -Yes! really. It’s a complete CPU. You can play most of the latest 3D and 2D games available in market. -Performance of this device is comparable with smartphones.Specifications of Android 4.0 Mini PC -OS: Android 4.0

-Main Chip: Allwinner A10/ 1.5 GHz Cortex-A8 -Memory: 1GB -Storage: 4GB -Graphical processor: 2D/ 3D/ OpenGL ES2.0(AMD Z430)/OpenVG1.1(AMD Z160) 27M Tri/sec -Network: Wireless 802.11b/g, WAPI(Ralink8188) -Expand Memory: Micro TF 2-32GB -IO/Ports: Micro 5pin USB/ USB2.0 data transfer/ OTG and host expand -Keyboard: Support virtual keyboard, support 2.4G wireless keyboard, fly mouse -Audio: AAC, AAC+, eAAC+, AMR-NB, AMR-WB, QCP, MP3, WMA, WAV, MIDI, M4A -Video: WMV/ASF/MP4/3GP/3G2M4V/AVI/MJPEG/RV10/DivX/VC-1/MPEG-2/MPEG-4/H.263/H.264/720P, 1080P, 720*480-Andriod APP: Youku,Tudou,QQ,Youtube,Twitter,AngryBird,Office,Gmail,Browse,Skype -HDMI: 1080P, 2160P  

What is CryptoParty? Interested parties with computers and the desire to learn to use the most basic crypto programs. CryptoParties are free to attend and are commercially non-aligned. Privacy is necessary for an open society in the electronic age. Privacy is not secrecy. A private matter is something one doesn't want the whole world to know, but a secret matter is something one doesn't want anybody to know. Privacy is the power to selectively reveal oneself to the world.

1.1 Cryptography is Dangerous (and Beautiful)

2 Basics first

3 PGP / GPG