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Comment: Tesla DOES use laptop batteries (Score 2) 54

by DrYak (#49607355) Attached to: Tesla Adds Used Models To Its Inventory, For Online Purchase

No, the ones in our notebooks and phones don't last so long, because size and weight are more important than lasting 10 years. Cars are designed differently, for different longevity/size/weight tradeoffs than are portable electronics.

Except that Tesla (and Smarts, and the few other cars which use batteries manufactured by Tesla) use *the exact same kind* of battery cells as regular laptops (on purpose, because they are cheap and easy to source due to the economy of the scale at which they are produced).

The difference isn't the battery it self (it the exact same cell), it's the battery management software, and the usage pattern.

- Lithium batteries age with the number of cycle they go through. It happens really often that a laptop is drained all the way down to 0% or nearly 0% (lithium batteries hate that). Whereas most of the daily commute Tesla cars are subjected to are short trips that only eat a fraction of their charge.

- The more violent the discharge rate, the faster the lithium battery will age. Under heavy load, a laptop battery will get completely drained in hour or two max. On the other hand, given its range and typical speed limitation, it would take at least 4-5 hours to drain completely a Tesla. i.e.: overall the Tesla eats up much more total power than your laptop (obviously), but each of the cells is put to less stress as it needs to deliver a much lower peak current.

(The two above are also the reason why the *extended life* batteries (e.g.: 9 cells instead of 6 cells) in laptops tend to age much slower).

- Also lithium batteries are very sensitive to temperature / environment. Whereas it's not that much controlled in a laptop (the battery tends to be right next to very hot components like CPU and GPU), Tesla car batteries have almost their own A/C system.

so in short:
- no they are exactly the same batteries. but each takes completely different kind of abuses and thus at the end they tend to age differently.

Comment: Re: Why is is the material support provision bad? (Score 1) 120

lol. This is an administration that defines the word "militant" as meaning any male that isn't a child or pensioner. "Material support for terrorism" doesn't mean anything at all, given that the last 15 years have shown governments will happily label anything they don't like as terrorism. Bear in mind the primary roadblock that prevents the UN agreeing on a definition of terrorism is western nations (i.e. America's) insistence that people who resist foreign occupation of their countries must be considered terrorists, and Arab nations insistence that they mustn't.

Comment: Re:It changes when the 'wrong' people do it. (Score 1) 17

by smitty_one_each (#49606063) Attached to: When did Net Neutrality change?

There are plenty people that can actually work happily together without any such nonsense.

I defy you to show a non-trivial, worked example. Even for a stylized case like a symphony, there are still interpersonal rivalries at work. The "entropy of the human soul" can be minimalized (at, say, a monastary), but never retired. And a symphony or a monastery are miniscule, edge cases.

Comment: Public acceptance (Score 1) 44

by DrYak (#49605805) Attached to: Robots In 2020: Lending a Helping Hand To Humans (And Each Other)

I'm really surprised that fast food and other low-skill, low-wage work hasn't been replaced by robots already. {...} Fast food isn't a skill. It doesn't even come close to coffee shop barista {...} If it costs $200,000 per year to pay employees to work a fast food restaurant, and that cost can be reduced to $60,000 per year by the introduction of a half a million dollars of machinery that will last for a decade, these companies would be nuts to not replace workers with robots.

Indeed. But on the other hand, we human tend to be social being. And we tend to appreciate contact with other humans.
Some older people would insist that they *definitely* need to interact with a human being taking order at the cash register, and they *definitely* need to see humans flipping burger in the kitchen behind.
They would find alienating to pass order to a machine and have their burger prepared by a assembly-line machine.
And add to that, that people will be down in the streets protesting that they are loosing jobs, and you can see why fast-food chains are a bit reluctant to start automate everything.

But old people get older, and newer younger generations come. And our current generation, is way too much self-absorbed to care. We are too much busy tweeting and posting on facebook while in line to even care if our orders are taken by an automat or a real person : it's just a distraction delaying us from typing a reply to a youtube comment on the smartphone.

The barriers to accelerating fast-food with assembly-line like robots isn't a technical one, but a sociological one. The fast-food companies needed that the population gets used to it.

Comment: Depends (Score 2) 75

by DrYak (#49596103) Attached to: Once a Forgotten Child, OpenSSL's Future Now Looks Bright

For the "many eyes" to work, there are quite few requirement.

Yes, being opensource is a requirement, but is not the single only requirement.

The code need to be actually readable and to attract users motivated to check it.
That wasn't the case. OpenSSL's code is known to be really crappy, with lots of bad decisions inside. Any coder trying to review it will have their eyes starting to bleed.
It doesn't attract people who might review it. It only attracts the kind of people who just want to quickly hack a new feature and slap it on the top, without having a look at what's running underneath.

The code need also to be reasonably accessible to code review tools.
Lots of reviewers don't painfully check every single last line of code by hand. Some use tools to do controls. OpenSSL has had such a series of bad decision in the past, that the resulting piece of neightmare is resistant to some types of analysis.

Comment: Tool assisted review (Score 1) 75

by DrYak (#49596057) Attached to: Once a Forgotten Child, OpenSSL's Future Now Looks Bright

The problem is that some of the design decision behind openssl are so aweful that some of the code review tools just don't work well to detect bug.

Hearthbleed has specifically resisted to valgrind, because the geniuses behind openssl had implemented they own memory management replacement functions in a way that is resistant to memory analysis.
The memory porblem went undetected.

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