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Comment Re:Obama administration supports backdoors (Score 1) 100

Having the code for the back door open to the public is like giving away keys to anyone and everyone who wants it. It would render any encryption useless.

However, I think the OP is confused about things a little. Obama is pushing for private companies to install back doors so the government can spy on you. This article is about the source code for publicly funded software being open. Your phone is not government funded software so that's actually two different things.

Comment Re:The thing is (Score 1) 130

You forgot to factor in that the sun is only up for half the day (on average). So only 12 hours a day will have usable light. My math rounds out at 231 days per mole. Factor in real world limitations like the effect of weather and I would estimate somewhere in the neighborhood of a year per mole when it's all said and done. I think they're going to need a whole lot of these things to be actually useful.

Still in all, it's a good advancement in the right direction.

Comment Re:peril impervious denominator goggles (Score 1) 188

It's about cost-benefit ratio. Supporting all of the dying phone systems costs money. With fewer and fewer people using something other than Android or iPhone, there is no real benefit to WhatsApp to expend the resources supporting them. Sure, they're not dead yet, but they have zero future. The law of diminishing returns is what's driving this decision. The company has no obligation to expend resources in a way that doesn't make financial sense.

It sucks for the dwindling pool of users who are not on the top 3 platforms but there's not much they can do about it. It's driven by the market like it or not.

Comment Tail wagging the dog? (Score 2) 188

With over 1 billion active users, and the backing of Facebook, is WhatsApp finally reducing the mobile landscape to a three-horse race ?

This summary is entirely backwards. The mobile market is already a 2 horse race (with Windows phone only still on the track because of the insane money Microsoft has poured into it). WhatsApp is only responding to that fact, not driving it. There is no point in them supporting outdated products with < 1% of the market and no future. WhatsApp support (or lack thereof now) will have absolutely zero impact on the market.

Comment Re:Can you work with an image? (Score 1) 364

There's only one problem with that. Cracking up to 37 characters of unicode characters (even if you don't use the entire 200K+ set of printable characters) is slightly more difficult to brute force than the 256 bit AES key...

By my math, with 37 characters, you only need 121 unicode characters (not 121K. Just 121) to make roughly as many permutations as a 256 bit AES key.

Comment Re:Useless Change (Score 2) 383

The OP was talking about engines that can advance or retard a single pattern cam. And when you have just one cam profile, you can only change the relative timing. The duration and lift stay fixed. Duration is the number of degrees of camshaft rotation that the valve is open. Adjusting when a camshaft opens the valve doesn't change how long it stays open, or how far it opens for that matter. Electrically controlled valves can vary all 3 of those things.

Sure, the VVT tech changes from one camshaft profile to a second one. But that's all they can choose from. You either use one or the other. You might be able to squeeze 3 profiles in there if you use a DOHC setup that splits the intake and exhaust lobes between two physical camshafts and gives you room to fit the multiple patterns. But it would be a lot more complicated to do that. And you're still limited to a few fixed profiles. Electrically controlled valves do not have this limitation.

Electrically controlled valves, in theory, have "infinite" adjustability (within certain limits). You can have dozens, hundreds, probably even thousands of profiles to choose from. All you have to do is have the computer pick the profile based on load, throttle position, etc. and it changes instantly.

Comment Re:Bullshit (Score 1) 383

I have to wonder if solenoid activated hydraulic systems could be used to actuate valves efficiently and with good longevity. That would let the solenoid just open a port rather than having to push a valve directly. The fluid would push against the spring loaded valve. Though you might need two solenoids. One to open and inject the high pressure fluid and one to open a large drain to let the valve close quickly. I would think just having an always open drain would mean you'd have to flow a whole bunch of fluid under very high pressure to overcome the drain's capacity and actually open the valve.

Comment Re:Bullshit (Score 1) 383

The old 50's Corvettes used purely mechanical fuel injection that not only was complex and hard to maintain, it required frequent maintenance. It was phased out after 1965. It bears literally zero resemblance to modern fuel injection systems. The first mass produced digitally controlled fuel injection made by GM showed up in the 1982 Corvette. It was a throttle body injection system that, in various forms, lasted through the 80's into the early 90's. But by 1984, GM started with port fuel injection that has evolved several generations but, in basic concept anyway, hasn't radically changed. All they've done is reconfigure the intake runners, the injector locations, gotten rid of the distributor in favor of a crank position sensor, etc. And each generation gets a little bit better. One could argue that the new direct injection, where they moved the injector from the intake runner into the cylinder head, is a significant change. And I'll grant that.

Comment Re:Useless Change (Score 1) 383

The advantage you gain is not just the ability to vary the timing of the valve events, but you can change the duration and lift as well. A camshaft only lets you vary how much sooner or later you open the valve but it's always open the same duration and the same lift.

Theoretically, with enough fine control over the valves and a good computer to control it, you could do away with the throttle altogether and use the valve duration, lift, and timing as the throttle.

Comment Re:Camshafts control flow timing not firing (Score 1) 383

False. A distributor controls which cylinder should fire, not when.

Technically, that's false depending on what time period you get your distributor from in an automobile. Leading up to the 1980's all automotive engines used mechanical advance mechanisms (either spring loaded counter weights, engine vacuum applied to a diaphragm, or both) to advance or retard timing. It wasn't until the 1980's when ignition trigger events from the distributor were passed to a computer that determined the actual spark timing. Modern engines have supplanted the distributor with the crank position sensor but only because it reduces the number of moving parts and cost of building the engine.

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