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Comment: Re:apples real problem is utility. (Score 1) 54

by mccalli (#49377573) Attached to: Apple Extends Its Trade-In Program
You understand that the release of the latest iPhone generations produced the highest rate switchers away from Android and over to the iPhone, right?

I don't mind the debate - I've had an iPhone since the 3GS but was and am seriously looking at switching away for various reasons. The debate should be based on fact though, and the facts are that Apple doesn't have a dearth of people moving off other platforms and over to its own.

Comment: Re:DARPA SJW (Score 1) 98

by Waffle Iron (#49375177) Attached to: Robots4Us: DARPA's Response To Mounting Robophobia

If it's acceptable for machines to be playground equailizers than all schoolchildren should be issued sidearms and be given training on how to employ deadly force to stop bullying.

Projectiles from your puny weapons will simply bounce off my armored playground robot.

Now, hand over your weapon and your lunch box to the machine.

Comment: Re:Why does it need a 5 speed gearbox?? (Score 1) 165

by gTsiros (#49370431) Attached to: At the Track With Formula E, the First e-Racing Series

google brushless motor efficiency, look at images if you don't fancy reading.

i said rarely. consider that in f1 the clutch is to be operated 4-5 times. once at the start, two or three for pit stops and one left over for emergency/unforeseen events.

once again, you don't need a clutch for an electric motor, whether it is mated to a gearbox or not

Comment: Re:Why does it need a 5 speed gearbox?? (Score 1) 165

by gTsiros (#49369553) Attached to: At the Track With Formula E, the First e-Racing Series

the whole "max torque from 0 rpm" phrase that is thrown around is quite misleading. While true that a motor exerts its maximum torque at zero rpm (and drops linearly as rpm increases), it also has the worst efficiency. maximum power draw (it's a short circuit!) and minimum power output (it's not moving is it?). peak efficiency is at a specific rpm, thus a gearbox is needed *for efficiency*.

Comment: Power to weight ratio (Score 4, Informative) 165

by gTsiros (#49369101) Attached to: At the Track With Formula E, the First e-Racing Series

to put 8 kW/kg into perspective, all commercial brushless dc motors are at 4 kW/kg and it is a limitation of the materials used.

Commercial internal combustion engines range from 1 kW/kg to *maybe* 3 kW/kg if it is turbocharged to the point of sacrificing engine longevity and formula 1 engines are at around 5 kW/kg

although i suspect they saved weight by using the vehicle frame as (part of?) the stator, a perk of making a motor for a very specific purpose.

Comment: Re:Still photos (Score 1) 440

by Waffle Iron (#49365231) Attached to: Why the Final Moments Inside a Cockpit Are Heard But Not Seen

A compromise could be the use of still photographs..

Why compromise?

All the city bus drivers in my area are on video surveillance. We routinely get to see footage of accidents and altercations with crazed passengers on the local news.

If it's good enough for a bus, it should be good enough for someone responsible for the safety of a 500mph $200M machine.

Comment: Re:Not really needed (Score 1) 40

by Waffle Iron (#49349923) Attached to: MIT Debuts Integer Overflow Debugger

If his garbage causes you take take a different flow of execution, however, that provides him a way to reach bugs in the little-used parts of your code.

The different flow of execution triggered by an overflow trap should almost always be a simple call to "abort()". At this point, your program has already failed and should be stopped.

I disagree with your premise. Garbage input values should be checked and rejected in software before the overflow ever occurs. The hardware overflow check should be a last resort to enforce this at every instruction step, and in the worst case it converts privilege exploits into less serious DOS attacks.

Allowing "garbage output" as you propose just creates more opportunities for attacks when that output gets consumed somewhere.

Good day to avoid cops. Crawl to work.