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Second From Wikipedia, the free encyclopedia Jump to: navigation, search This article is about the unit of time. For other uses, see Second (disambiguation). A light flashing approximately once per second The second (SI unit symbol: s) is the International System of Units (SI) base unit of time[1] and also a unit of time in other systems (abbreviated s or sec[2]). Between 1000 (when al-Biruni used seconds) and 1960 the second was defined as 1/86,400 of a mean solar day (that definition still applies in some astronomical and legal contexts).[3][4] Between 1960 and 1967, it was defined in terms of the period of the Earth's orbit around the Sun,[5] but it is now defined more precisely in atomic terms. Seconds may be measured using mechanical, electric or atomic clocks.

Coulomb

The coulomb (symbol: C) is the SI derived unit of electric charge. It is defined as the charge transported by a steady current of one ampere in one second: One coulomb is also the amount of excess charge on the positive side of a capacitance of one farad charged to a potential difference of one volt:

LILLIPUTIAN SYSTEMS ANNOUNCES WAFER MANUFACTURING SUPPLY AGREEMENT WITH INTEL AND EQUITY STAKE BY INTEL CAPITAL

Lilliputian Systems, Inc. (www.lilliputiansystems.com), developer of the world’s first Personal Power™ solution for consumer electronics devices, today announced that it has signed a Wafer Manufacturing Supply Agreement with Intel.  Additionally, Lilliputian Systems announced that Intel Capital, Intel Corporation’s global investment arm, has taken an equity stake in Lilliputian Systems.

In connection with the agreement, Intel will manufacture and supply production wafers, which are critical in the production of all of Lilliputian Systems’ product lines, most importantly its first product – the revolutionary USB Mobile Power System.

Explore Google Search

Search is at the heart of everything we do at Google. Our engineers work every day to solve the hardest search problems, and thus improve your online experience. Here's a glimpse at what they do, the features they've built and the remarkable user stories that inspire our work.

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.

Metre From Wikipedia, the free encyclopedia   (Redirected from Meter) Jump to: navigation, search This article is about the unit of length. For other uses of "metre" or "meter", see meter (disambiguation). 1 metre = SI units 100 cm 1000 mm US customary / Imperial units 3.2808 ft 39.370 in The metre (meter in the US), symbol m, is the base unit of length in the International System of Units (SI). Originally intended to be one ten-millionth of the distance from the Earth's equator to the North Pole (at sea level), its definition has been periodically refined to reflect growing knowledge of metrology. Since 1983, it has been defined as "the length of the path travelled by light in vacuum during a time interval of 1 ⁄ 299,792,458 of a second.[1]

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).

Two military spy telescopes, just as big and powerful as Hubble, donated to NASA

The telescopes were built by private contractors for the National Reconnaissance Office, one of 16 U.S. intelligence agencies. Each have 2.4-meter (7.9-foot) mirrors, just like the Hubble, but they have 100 times the field of view.

the telescopes, built in the late 1990s and early 2000s, are now technologically outdated, at least for intelligence operations, despite being just as powerful as Hubble. Now that something that’s worth taking into consideration. Moreover, these telescopes worth hundreds of millions of dollars have never seen operation! Instead they’ve been shelved in a warehouse somewhere, of course, classified. And they might find themselves, yet again, blocked in a warehouse, since NASA, on a string budget, doesn’t have the necessary cash to fit them.

$49.99

BELKIN Belkin WeMo Home Automation

Turn electronics on or off — from anywhere. Operates over Wi-Fi and mobile internet, at home and away. You’ve already got everything you need: WeMo works with your existing Wi-Fi router and any iPod touch, iPhone, iPad - iOS 5 or higher. Put your electronic devices on a schedule. Modular system. You can add additional WeMo Switches easily, any time. Control as much or as little of your home as you want to.

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™.

ikiLeaks says you can find them through wikileaks.ch, which redirects to a dotted ID. People exchange this information on Twitter. So in a weird sneaker-net sort of way we have implemented a human DNS.

All the while there's a huge glaring 800-pound-gorilla elephant-in-the-room size contradiction. The pols say that businesses can't support WikiLeaks, but the Guardian and the NY Times and the newspapers in Pakistan, Indonesia, Israel -- all over the world -- they're businesses too. So if they're really serious about this, we're in First Amendment territory. They ought to be careful, because the politicians depend on these businesses to sell their product. Without them, they have no way to lie to us.   See the problem isn't that WikiLeaks is lying, the problem is that they're telling the truth. This is not business as usual. 

It seems to me that at the end of this chain is BitTorrent. That when WikiLeaks wants to publish the next archive, they can get their best practice from eztv.it, and have 20 people scattered around the globe at the ends of various big pipes ready to seed it. Once the distribution is underway the only way to shut it down will be to shut down the Internet itself.

«Nous exposons notre cerveau à cet environnement et nous lui demandons de faire des choses qui ne font peut-être pas partie d'une évolution normale, résumait il y a quelques semaines le neurologue américain Adam Gazzaley, de l'Université de Californie, dans les pages du New York Times.

le mythe de l'humain multitâche et hautement productif avec son iPhone en main qui lui permet de suivre les cours de la Bourse, de programmer sa télévision à distance, de gérer sa bibliothèque musicale, de tenir à jour son agenda, d'informer ses amis de ses déplacements tout en téléchargeant des livres d'histoires à lire à ses enfants le soir avant de se coucher.

La technologie tend à reconfigurer les connexions du cerveau, mais elle est aussi contre-productive lorsqu'utilisée avec excès, estiment les chercheurs, et le fléau touche certainement la majorité des ménages dans les sociétés hautement numériques

The conversion of sunlight into electricity has been dominated by photovoltaic and solar thermal power generation. Photovoltaic cells are deployed widely, mostly as flat panels, whereas solar thermal electricity generation relying on optical concentrators and mechanical heat engines is only seen in large-scale power plants. Here we demonstrate a promising flat-panel solar thermal to electric power conversion technology based on the Seebeck effect and high thermal concentration, thus enabling wider applications. The developed solar thermoelectric generators (STEGs) achieved a peak efficiency of 4.6% under AM1.5G (1 kW m−2) conditions. The efficiency is 7–8 times higher than the previously reported best value for a flat-panel STEG, and is enabled by the use of high-performance nanostructured thermoelectric materials and spectrally-selective solar absorbers in an innovative design that exploits high thermal concentration in an evacuated environment.

XBee Tutorial: Setting up your XBees

XBees are wireless transceivers from Digi that implement the Zigbee protocol. They are simple devices that we can use to set up serial communications between our applications. Using the XBee tutorial you will have your devices talking in no time!

The unit is light weight (2.5 lb), portable, low cost ($10-$20) and can be used to recharge single cell batteries at from 1-3.5 amps. It can be made from a cordless electric drill in a primitive environment. The simplest way of how to make a hand crank DC generator using a standard 12, 14.4 or 18 Volt Cordless drill

With no modification hook an alligator clip jumper to the two charging terminals (on the bottom that the battery plugs into). See picture below. Note that when a 14.4 Volt drill is laid down pointing to the left then the upper terminal is most likely to be the plus and the lower terminal the minus for these units.