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User: wagnerrp

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  1. Re:Well that seems just fine on Are US Hybrid Sales Peaking Already? · · Score: 1

    The vast majority of the cost of the Tesla is in the battery. Drop the battery for a small energy buffer and a ~50hp generator and you're down in conventional car territory.

  2. Re:I can't buy one on Are US Hybrid Sales Peaking Already? · · Score: 1

    Some cars have brake air, and although I suppose you could consider that a fluid, the air isn't there to actuate the brakes, merely to release them. The brakes work completely mechanically on their own.

  3. Re:I can't buy one on Are US Hybrid Sales Peaking Already? · · Score: 1

    All hybrids have transmissions. No one uses direct-drive electric motors.

  4. Re:I can't buy one on Are US Hybrid Sales Peaking Already? · · Score: 1

    You only need good low end torque if you're towing something, and you're not going to be towing shit in a Prius. Cars need good mid-range torque for being able to safely accelerate to highway speeds before the end of an on ramp, and torque at speed means power, power a Prius simply doesn't have.

    The typical passenger car doesn't need more than ~40hp sustained, but it needs several times that peak.

  5. Re:I can't buy one on Are US Hybrid Sales Peaking Already? · · Score: 0

    If you have an electric power train, then you don't have a hybrid. You have an electric car, and optionally a generator. Somewhere along the line a decade or so ago, someone got the stupid idea that hybrids were the future, and we've been stuck with them ever since, rather than getting a proper mass market electric.

  6. Re:Backup? on One Developer's Experience With Real Life Bitrot Under HFS+ · · Score: 1

    Then you store three copies of the checksum, and compare.

  7. Re:Bitrot not the fault of filesystem on One Developer's Experience With Real Life Bitrot Under HFS+ · · Score: 1

    Isn't that RAID6?

  8. Re:It's the contents of the files... on One Developer's Experience With Real Life Bitrot Under HFS+ · · Score: 1

    Sufficiently advanced RAID implementations will carry checksums of those blocks for exactly that purpose.

  9. Re:Backup? on One Developer's Experience With Real Life Bitrot Under HFS+ · · Score: 1

    Video files are harder to figure - a corrupted bit could easily get overlooked.

    Again, it depends on whether it is compressed or not. A corrupted bit in video with only interframe compression will look just like a damaged JPEG. You may have an unreadable frame, or may have a corrupted macroblock or two in that frame. A corrupted bit in video with intraframe compression will smear that corrupted frame or macroblock for potentially several seconds until you hit the next I-frame to flush the image.

    You can spend a lot more money getting near perfect replication but I don't think many people are willing to have a system with ECC memory throughout the chain.

    The common solution to this issue is software, not hardware. You have your filesystem compute and store checksums at the block level, and you give your filesystem access to redundancy, either through redundant copies on disk, or multiple parity disks. When your filesystem reads the data, it checks it against the checksum, and if needed, recomputes the data from the redundant storage. That said, you do still need ECC memory on the CPU doing those calculations for it to be reliable.

  10. Re: Legacy file systems should be illegal on One Developer's Experience With Real Life Bitrot Under HFS+ · · Score: 1

    Actually, no, they won't. The chances of bitrot occurring in the same location on both your primary store and your backup, such that neither had viable data to recover, is astronomically low.

  11. Re:Weak magnetic fields on the moon. on Moon Swirls May Inspire Revolution In the Science of Deflector Shields · · Score: 1

    It's a small magnetic field, only providing localized protection. It is not extending thousands of miles above the planet to protect the upper atmosphere.

  12. Re:War of government against people? on America 'Has Become a War Zone' · · Score: 4, Insightful

    Town A has 5 police per thousand people, and 3 crimes reported per thousand people every day. The next year, they increase the number of police to 7 per thousand people, but crime rates go up to 5 crimes reported per day. Despite the negative correlation, this doesn't disprove the idea that having a greater police presence reduces crime.

    Ahem... I hate to have to tell you this, but yes it did. The simple fact is: you had greater police presence, but crime went up. Your hypothesis has been disproved.

    In an uncontrolled study, it disproves nothing. The data could be a result of gun proliferation reducing crime. The data could just as well be a result of gun proliferation increasing crime, only for those crime levels to be affected more strongly downwards by some other independent cause. You can't simply plot a bunch of statistics and call it a day. You have to exhaustively search through a large enough data set to definitively isolate that single variable amongst all others.

    If you find "stop, drop, and roll" ineffective while someone is pouring gasoline on you, you haven't disproven the technique, you're merely found one situation in which other factors are overriding it.

  13. Re:hype on New Car Can Lean Into Curves, Literally · · Score: 1

    Nothing I have said disagrees with that wiki article.

  14. Re:Mainstream hydraulics? on New Car Can Lean Into Curves, Literally · · Score: 1

    The crackers are only necessary

    FTFM...

  15. Re:hype on New Car Can Lean Into Curves, Literally · · Score: 1

    [Please read comments carefully before posting.]

    I stated the fact that many suspensions attain desirable negative camber while turning as a consequence of body roll.

    Yes, that is incorrect. They experience positive camber, as the load on the outer wheel causes the top of the outer wheel to flex outward. As explained, negative camber is never desirable. The only reason to configure your suspension for negative camber is so that when turning, loads on your suspension bring your wheel back to neutral camber for maximum traction.

  16. Re:Same thing on New Car Can Lean Into Curves, Literally · · Score: 1

    Actually, you have it backwards. They're generating body roll inward, so instead of feeling lateral Gs from the turn, the driver experiences positive Gs. The driver feels that the car is not turning as hard.

  17. Re:hype on New Car Can Lean Into Curves, Literally · · Score: 1

    Cars can gain traction in turns if body roll results in negative tire camber (especially on the outside wheel).

    That's not accurate. Cars have their best traction when at neutral camber, meaning the surface of the tire is flat against the surface of the road. In a turn, the outside tire will be loaded more heavily than the inside, and will tend to lean towards positive camber. Thus, if you "pre-stress" the suspension with negative camber, such that lateral load in the corner increases the tire to neutral camber, you will gain traction.

    Of course, setting up your suspension for negative camber will make your tire wear poorly, so you really need tires that are designed to be used with negative camber, and will result in poor grip when not turning, so doing it on anything that is not explicitly a track car is just stupid.

  18. Re:But it gives the driver the wrong impression on New Car Can Lean Into Curves, Literally · · Score: 1

    These cars are at 90 degrees of the "driving feeling" concept.

    Of course it has nothing to do with feeling like you're in a performance vehicle. It has to do with being more comfortable, and we are more comfortable with positive Gs than lateral Gs.

  19. Re: Old tech on New Car Can Lean Into Curves, Literally · · Score: 1

    The Corolla is only half the height of the ML. That helps a lot in curves.

    And more than half a ton lighter.

  20. Re:Yeah. Right. on New Car Can Lean Into Curves, Literally · · Score: 2

    Just banking the car does not mean the car's tires will experience any less lateral Gs, or be able to sustain any greater lateral Gs. Cornering performance will not change.

  21. Re:Yeah. Right. on New Car Can Lean Into Curves, Literally · · Score: 1

    Yes. ABS is the answer, all the time. You don't just stomp your brakes like an idiot because you have ABS. You still "threshold brake" as close as possible. ABS allows you to operate much closer to that threshold, as it recovers much more quickly when you exceed it.

  22. Re:Yeah. Right. on New Car Can Lean Into Curves, Literally · · Score: 1

    No they can't, because the threshold is continuously changing, there is no way to accurately know the position of that threshold, and once you cross the threshold, you have to drop way off to get back down below it. Operating it digitally is the only way to ensure you regain grip and maintain braking performance. It's a similar principle as to why it's easier to break AC than DC. You can build DC circuit breakers, but you need a lot of circuitry to provide that zero quench that AC experiences natively.

  23. Re:Still not as good as Bose Active suspension on New Car Can Lean Into Curves, Literally · · Score: 1

    Unlike conventional dampers, which transmit vibrations to the vehicle occupants and sacrifice comfort, the wheel damper in the Bose system operates without pushing against the car body, maintaining passenger comfort.

    So in other words, it works on magic... If they're able to generate a force without incurring a counter force, then why the fuck are we even bothering with wheels? They've invented a reactionless drive system. Get these people to NASA, stat!

  24. Re:Gimmick on New Car Can Lean Into Curves, Literally · · Score: 2

    All cars lean. The design of the suspension just decides how much it leans.

  25. Re:Mainstream hydraulics? on New Car Can Lean Into Curves, Literally · · Score: 1

    In this case, hackers. The crackers are on necessary if there is some form of protection on the car's control data bus preventing you from manipulating it yourself. Such buses typically have no protection but physical.