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Comment: Re:Obvious (Score 0) 250

by Saba (#29104669) Attached to: iPhone 3GS Is Number One In Japan
Japanese phones are check lists of who has the most features: The one with the most sells the best.

Things like TV and radio are just silly features concocted to make the feature list even longer -- the next crazy idea is adopted by all the manufacturers in the next product iteration.

It's this mindset that people look for, unfortunately. And the industry caters to the demand.

PS: This also extends to other products too. Japanese motorcycles, for example, revolve around who has the largest numbers for that manufacturing year.

Comment: This is called granular flows (Score 5, Interesting) 192

by Saba (#28494375) Attached to: Researchers Discover That Sand Behaves Like Water
Sand belongs to a group of things called granular media. This includes things like pellets, ores, polymers, etc.

We typically regard the size of the particles to be larger than 1Âm. Any smaller and you have to start to take into account interparticle forces such as electrostatics and Van der Waals.

Trying to work out exactly how granular media behaves is tricky. Sometimes it behaves like a solid (sand on a beach, say -- you don't sink into it) and sometimes it behaves like a fluid (you can pour the grains of sand from a beach through your fingers). The example given here shows how it can behave inbetween solid objects (mechanics) and liquids (fluid dynamics). There's a large body of statistical and simulation results that try to understand what's going on, but nothing exists like Navier-Stokes does for liquids.

There's a lot of strange and unintuitive behaviour that arises out from studying these sorts of materials, and it's *extremely* important to industry. For example how granular media has a self-sorting behaviour when you subtly vary the size or mass of each particle.

The article shows another example of it.

Comment: Linux already has this (Score 5, Informative) 248

by Saba (#28134927) Attached to: Windows 7 Hard Drive and SSD Performance Analyzed
Linux already supports SSD's and other flash media by having a noop scheduler. The basic premise is that devices that don't depend on mechanical movement to access data don't need reordering of requests. This is also the scheduler you use if you have an advanced controller (RAID, etc) that is capable of doing it's own I/O rescheduling.

To see what scheduler you are running (on this case /dev/sda):

# cat /sys/block/sda/queue/scheduler
noop anticipatory deadline [cfq]

Here the completely fair scheduler is currently running. To swap to the noop scheduler:

# echo noop > /sys/block/sda/queue/scheduler
[noop] anticipatory deadline cfq

What sin has not been committed in the name of efficiency?