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The opposite of virtualization: Calxeda's new quad-core ARM part for cloud servers. On Tuesday, Austin-based startup Calxeda launched its EnergyCore ARM system-on-chip (SoC) for cloud servers.

The opposite of virtualization: Calxeda's new quad-core ARM part for cloud servers

At first glance, Calxeda’s SOC looks like something you’d find inside a smartphone, but the product is essentially a complete server on a chip, minus the mass storage and memory. The company puts four of these EnergyCore SoCs onto a single daughterboard, called an EnergyCard, which is a reference design that also hosts four DIMM slots and four SATA ports. A systems integrator would plug multiple daughterboards into a single mainboard to build a rack-mountable unit, and then those units could be linked via Ethernet into a system that can scale out to form a single system that’s home to some 4096 EnergyCore processors (or a little over 1,000 four-processor EnergyCards). The current EnergyCore design doesn’t support classic, hypervisor-based virtualization; instead, it supports Ubuntu’s lightweight, container-based LXC virtualization scheme for system management.

Tutoriel: Drag and Drop JQuery, exemple avec une liste des tâches. Facile jQuery, css Après un tutoriel pour créer un diaporama simple avec JQuery, qui d’après vos commentaires vous a assez intéressé, voici un nouveau tutoriel basé sur le Drag and Drop.

Tutoriel: Drag and Drop JQuery, exemple avec une liste des tâches

L’exemple que nous allons voir est une liste des tâche simple, que je vous présente sous la forme d’une liste de courses. Le principe est simple, on ajoute des éléments, on les renomme, on modifie leur ordre et on les supprime. On va voir dans cet article comment utiliser de manière très simple la bibliothèque d’animations et d’interactions JQuery UI. Celle ci permet d’avoir « nativement » des interfaces pour pouvoir déplacer des éléments et contrôler où on les dépose (drag & drop) ainsi que pour les trier. Ces interfaces sont les suivantes : Mise en page et intégration Partie HTML Nous allons créer une page xHTML simple, composée des éléments suivants : Before Netscape: the forgotten Web browsers of the early 1990s. When Tim Berners-Lee arrived at CERN, Geneva's celebrated European Particle Physics Laboratory in 1980, the enterprise had hired him to upgrade the control systems for several of the lab's particle accelerators.

Before Netscape: the forgotten Web browsers of the early 1990s

But almost immediately, the inventor of the modern webpage noticed a problem: thousands of people were floating in and out of the famous research institute, many of them temporary hires. "The big challenge for contract programmers was to try to understand the systems, both human and computer, that ran this fantastic playground," Berners-Lee later wrote. "Much of the crucial information existed only in people's heads. " So in his spare time, he wrote up some software to address this shortfall: a little program he named Enquire. It allowed users to create "nodes"—information-packed index card-style pages that linked to other pages. Some years later Berners-Lee returned to CERN. Mosaic was soon spun into Netscape, but it was not the first browser. The CERN browsers Erwise. What makes the fuel go boom? Turbulence!

When most people picture explosions, they probably imagine a huge ball of expanding gas, perhaps with an action hero just barely outrunning the leading edge.

What makes the fuel go boom? Turbulence!

In reality, though, there are two types of explosions: deflagrations and detonations. Deflagrations are flames that propagate at subsonic speeds, and we encounter those in day-to-day life, in the pistons of internal combustion engines, and above Bunsen burners and gas stoves. Detonations, on the other hand, propagate at supersonic speeds and consist of hot, high-pressure reacting gases. These drive a shock wave that significantly compresses and heats up the oncoming gas. Typical flame speeds for deflagrations are on the order of centimeters to meters per second, while detonations expand at a speed three orders of magnitude faster (on the order of 1000 m/s).

So, how do detonations occur? Like the transition from laminar to turbulent flows, DDT is a complex process that is still not completely understood.