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Cloud Computing – The next generation

Cloud Computing

Definition:(from wikipedia)

Cloud computing is Internet-based computing, whereby shared resources, software and information are provided to computers and other devices on-demand, like a public utility.

It is a paradigm shift following the shift from mainframe to client-server that preceded it in the early ’80s. Details are abstracted from the users who no longer have need of, expertise in, or control over the technology infrastructure « in the cloud » that supports them. Cloud computing describes a new supplement, consumption and delivery model for IT services based on the Internet, and it typically involves the provision of dynamically scalable and often virtualized resources as a service over the Internet. It is a byproduct and consequence of the ease-of-access to remote computing sites provided by the Internet.

The term cloud is used as a metaphor for the Internet, based on the cloud drawing used in the past to represent the telephone network, and later to depict the Internet in computer network diagrams as an abstraction of the underlying infrastructure it represents. Typical cloud computing providers deliver common business applications online which are accessed from another web service or software like a web browser, while the software and data are stored on servers.

A technical definition is « a computing capability that provides an abstraction between the computing resource and its underlying technical architecture (e.g., servers, storage, networks), enabling convenient, on-demand network access to a shared pool of configurable computing resources that can be rapidly provisioned and released with minimal management effort or service provider interaction. »[7] This definition states that clouds have five essential characteristics: on-demand self-service, broad network access, resource pooling, rapid elasticity, and measured service.

The majority of cloud computing infrastructure, as of 2009[update], consists of reliable services delivered through data centers and built on servers. Clouds often appear as single points of access for all consumers’ computing needs. Commercial offerings are generally expected to meet quality of service requirements of customers and typically offer SLAs.

Application(Alrealdy initiated)

 Smart electric network(US)

Amazon, Google, IBM(US)

Cloud Processing Center(China)

Review

Si l’on considère la naissance de l’ordinateur personnel est la première révolution de la technologie numérique, et la naissance d’Internet est la seconde, puis la naissance du cloud computing est le troisième. Avant longtemps, nous n’aurons pas à installer quoi que ce soit dans notre système du ordinateur parce que tout les logiciel serais dans le « cloud ». La seule chose que nous avons besoin est un accès à Internet. La étude scientifique qui nécessite une puissance de calcul super va être possible avec la technologie du cloud computing.

Cette technologie va changer notre façon de vivre

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MoogMusic Etherwave

février 16, 2010 Laisser un commentaire

MOOG MUSIC Etherwave Theremin

 

l’introduction du produit

The theremin is one of the oldest electronic instruments, and the only one known that you play without touching. Moving your hands in the space around its antennas controls pitch and volume. The Etherwave is an authentic adaptation of inventor Lev Termen’s original design.

The Etherwave is a quality musical instrument designed for ruggedness and portability. It has a five-octave pitch range and reliable spacing between notes for sophisticated playability. Antennas are nickel-plated 3/8″ brass tube and cabinets are furniture-grade hardwood, finished with a custom Moog stain. The Etherwave is fitted with an adapter for mounting on a standard microphone stand and works best with Moog’s TB-15 instrument amplifier.

 

L’histoire de la technologie theremin

The theremin was originally the product of Russian government-sponsored research into proximity sensors. The instrument was invented by a young Russian physicist named Lev Sergeivich Termen (known in the West as Léon Theremin) in October 1920 after the outbreak of the Russian civil war. After positive reviews at Moscow electronics conferences, Theremin demonstrated the device to Bolshevik leader Vladimir Lenin. Lenin was so impressed with the device that he began taking lessons in playing it, commissioned six hundred of the instruments for distribution throughout the Soviet Union, and sent Theremin on a trip around the world to demonstrate the latest Soviet technology and the invention of electronic music. After a lengthy tour of Europe, during which time he demonstrated his invention to packed houses, Theremin found his way to the United States, where he patented his invention in 1928 (US1661058). Subsequently, Theremin granted commercial production rights to RCA.

Although the RCA Thereminvox (released immediately following the Stock Market Crash of 1929), was not a commercial success, it fascinated audiences in America and abroad. Clara Rockmore, a well-known thereminist, toured to wide acclaim, performing a classical repertoire in concert halls around the United States, often sharing the bill with Paul Robeson. In 1938, Theremin left the United States, though the circumstances related to his departure are in dispute. Many accounts claim he was taken from his New York City apartment by KGB agents,[4] taken back to the Soviet Union and made to work in a sharashka laboratory prison camp at Magadan, Siberia. He reappeared 30 years later. In his 2000 biography of the inventor, Theremin: Ether Music and Espionage, Albert Glinsky suggested the Russian had fled to escape crushing personal debts, and was then caught up in Stalin’s political purges. In any case, Theremin did not return to the United States until 1991.[5]

Today Moog Music, Dan Burns of soundslikeburns.com[7] Chuck Collins of theremaniacs.com[7] Wavefront Technologies, Kees Enkelaar[8] and Harrison Instruments manufacture performance-quality theremins. Theremin kit building remains popular with electronics buffs; kits are available from Moog Music, Theremaniacs, Harrison Instruments, PAiA Electronics, and Jaycar. On the other end of the scale, many low-end Theremins, some of which have only pitch control, are offered online and offline, sometimes advertised as toys.

Fonctionnement

The theremin is unique among musical instruments in that it is played without physical contact. The musician stands in front of the instrument and moves his or her hands in the proximity of two metal antennas. The distance from one antenna determines frequency (pitch), and the distance from the other controls amplitude (volume). Most frequently, the right hand controls the pitch and the left controls the volume, although some performers reverse this arrangement. Some low-cost theremins use a conventional, knob operated volume control and have only the pitch antenna.

The theremin uses the heterodyne principle to generate an audio signal. The instrument’s pitch circuitry includes two radio frequency oscillators. One oscillator operates at a fixed frequency. The frequency of the other oscillator is controlled by the performer’s distance from the pitch control antenna. The performer’s hand acts as the grounded plate (the performer’s body being the connection to ground) of a variable capacitor in an L-C (inductance-capacitance) circuit. The difference between the frequencies of the two oscillators at each moment allows the creation of a difference tone in the audio frequency range, resulting in audio signals that are amplified and sent to a loudspeaker.

To control volume, the performer’s other hand acts as the grounded plate of another variable capacitor. In this case, the capacitor detunes another oscillator, which affects the amplifier circuit. The distance between the performer’s hand and the volume control antenna determines the capacitor’s value, which regulates the theremin’s volume.[9]

Modern circuit designs often simplify this circuit and avoid the complexity of two heterodyne oscillators by having a single pitch oscillator, akin to the original theremin’s volume circuit. This approach is usually less stable and cannot generate the low frequencies that a heterodyne oscillator can. Better designs (e.g. Moog, Theremax) may use two pairs of heterodyne oscillators, for both pitch and volume.

 

Resume

Je crois que la plupart des gens pensent qu’un homme doit au moins toucher à son instrument pour faire de la musique. C’est vrai pour la plupart des cas, mais pas pour Etherwave. Etherwave theremin est un produit de Moog Music. Il n’a pas de clavier, pas des cordes, meme pas une place qui semble etre touche. C’est simplement une petite boîte qui a deux antennes. Par simplement en déplaçant les mains en l’air autour des antennes, on peut faire de la musique. Non seulement vous pouvez contrôler le volume et la hauteur, vous pouvez également contrôler les paramètres comme  la fréquence du filtre, etc.

Cette technologie a déjà été utilisé dans le domaine des pratiques comme la musique électronique, le design sonore, et musique de film. Vous pouvez entendre le son de celui-ci dans la musique originale du film <the day the earth stood still>, <the sign> et <Black hawk down>.

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