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User: chgros

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  1. Re:Open source win on Apple AirPlay Private Key Exposed · · Score: 1

    information theory
    You probably mean "cryptography". Information theory is related but different.
    Anyway, cryptography makes a distinction between "obscure" and "secret". The idea is that good cryptography requires a secret. If something is in your possession (like a program on your disk), it's not secret to you (exception could be made for some secure chips that are designed specifically so that you can't read their secret).

  2. Re:Knuth, it may get you a job. on Book Review: The Art of Computer Programming. Volume 4A: Combinatorial Algorithm · · Score: 1

    How is calculating complexity "trivia"? Were the algorithms only described by name?

  3. Re:cool story bro on Smart Phone Gets Driver Out of a Speeding Ticket · · Score: 1

    > How sensitive would a device have to be, and how fast would it's
    > processor need to be, to detect a 10mph difference from the
    > frequency of a radio signal coming from space I wonder?
    Well, GPS works at about 1GHz; I think we can assume that a GPS receiver can count the number of cycles.
    10mph vs speed of light is about 10^-8, meaning about 10 cycles difference in a second. Seems measurable (GPS also provides very accurate time measurements; there might also be possibilities of measuring interference between signals from different satellites). The link I gave indicates an accuracy of about 0.5mph using a combination of doppler shift and location change measurements.

  4. Re:cool story bro on Smart Phone Gets Driver Out of a Speeding Ticket · · Score: 1

    Interesting.
    Either way, the fact that a given position is off doesn't really imply that the speed is wrong (as long as the position is consistently off).
    Also, it's the first time personally that I've said that, and there is obviously reason to think that some GPS receivers do use the doppler shift, so please don't be so mad.

  5. Re:cool story bro on Smart Phone Gets Driver Out of a Speeding Ticket · · Score: 2, Informative

    GPS doesn't measure speed by looking at how your position changes; it uses the doppler effect, which is fairly accurate.
    http://gpsinformation.net/main/gpsspeed.htm

  6. Re:Stupid Idea on Obama Calling For $53B For High Speed Rail · · Score: 1

    High Speed Rail would have the EXACT same security measures as airplanes, except they would be even less safe as blowing up track is easy, especially when you have hundreds of miles to choose from.
    How do you explain that, in the countries that have high speed rail, the airport security is the same as in the US but there's no such thing for trains?
    Bombing a plane is already not the most effective way to kill people, it's mostly for show. Attacking a subway would still work better than attacking a high speed rail (or low speed rail for that matter, I don't see why that would make a difference except for popularity, I guess)

  7. Re:Oh Yeah... on Big Brother Friends Facebook · · Score: 1

    Like in the good old 19th century.

  8. Re:Impossible on Kilogram Gets Controversial; Why Not Split the Difference? · · Score: 1

    Well, you could always define it at some extremum. For instance the triple point.

  9. Re:Awesome if it works on New Hampshire Bill Could Lead To Adoption of Approval Voting · · Score: 1

    > That weird concept of "throwing away your vote" when the person you voted for doesn't win is probably one of the biggest things wrong with our voting system
    In technical terms it's called "independence of irrelevant alternatives". It doesn't work in most voting systems.
    http://en.wikipedia.org/wiki/Arrow's_impossibility_theorem

  10. Re:Probably Wrong but Clearly Falsifiable on Polynomial Time Code For 3-SAT Released, P==NP · · Score: 1

    Playing games with ambiguity of the language I used?
    Not exactly. I was using the same language that the OP used, proving his point that the claim didn't imply P = NP. Also, in maths, "a" usually means "at least one", not "all".

  11. Re:Probably Wrong but Clearly Falsifiable on Polynomial Time Code For 3-SAT Released, P==NP · · Score: 1

    In fact it does suffice to show that the algorithm determines satisfiability of a 3-SAT instance in polynomial time.
    Really? I have an algorithm that can solve a 3-SAT instance in constant time.
    Algorithm:
    if(problem == "true") then "satisfiable" else "failure of classification"
    "true" is a 3-SAT instance with no variables

  12. Re:Driving with smartphones? on French Use Space Tech To Find Parking Spots · · Score: 2

    France has had a ban on driving with a cell phone in hand for a while now.

  13. Re:Totally inane on Replacing Traditional Storage, Databases With In-Memory Analytics · · Score: 1

    I'd LOVE to store entire large XML blocks in databases sometimes, and we decide not to because of space issues.
    Wait, do you mean that XML takes *less* space than a database? What kind of data do you have in there? I find that a binary format gzipped in a DB is way more efficient (time and space-wise) than XML.

  14. Re:Why on Beware of Using Google Or OpenDNS For iTunes · · Score: 1

    I don't see anything wrong with old school redirects though.
    Well, they only work for http, for one thing.

  15. Re:Dual core cell phone ? on Most Anticipated Tech Products of 2011 · · Score: 1

    why not just buy ready-made radio chips from people with the fabs to make them and do all the R&D on them?
    Gee, I wonder why not. Maybe because they're already doing it.

  16. Re:Stupid is as stupid does. on Real-Life Frogger Ends In Hospital Visit · · Score: 1

    I guess you don't mind if someone kills you now then.

  17. Re:Bad Idea on Paris To Test Banning SUVs In the City · · Score: 5, Informative

    The vast majority of CO2 emissions from cars come from driving them, not manufacturing them.
    See for instance page 4 of this report:
    http://www.pacinst.org/topics/integrity_of_science/case_studies/hummer_vs_prius.pdf

  18. Re:FFS on Why Anonymous Can't Take Down Amazon.com · · Score: 3, Interesting

    Thats a great example
    It also seems like a complete fabrication.
    "Uzvekia" returns 4 google hits, "Uzvekia Waterloo" only returning this post.

  19. Re:10-fold increase? on Tobacco Virus Could Boost Li Batteries · · Score: 1

    You have simply moved the combustion for energy from your engine to the power plant down the street.
    That's already a big deal. The plant down the street is way more efficient than a car.
    The only true answer to our car emissions problem is hydrogen fuel.
    Ah, yes, because generating/storing hydrogen is soooo efficient.

  20. Re:Wrong mix on Law and the Multiverse · · Score: 1

    > nothing in the law forbids any of both cases, even if there is an exploit to the system in the second one.
    Actually, there is a law:
    http://en.wikipedia.org/wiki/Rule_against_perpetuities

  21. Re:Useless with virtualization? on New Device Puts SSD In a DIMM Slot · · Score: 1

    Are you saying that a FC SAN will give you fewer IOps than this DIMM SSD?
    He's talking about latency, not throughput.

  22. Re:This was obvious. on US Supreme Court Expected Political Ad Transparency · · Score: 1

    So... Everyone should be unhappy so that individuals should be happy?

  23. Re:Obviously on Iran Acknowledges Espionage At Nuclear Facilities · · Score: 1

    That's a lot higher than your piece of pie
    In fact, that's a lot lower.
    1mL is about 1g (true for water, nearly true for alcohol)
    So, to have about 4mL of alcohol, you'd need about 10L of orange juice.
    BTW, here's your corrected link:
    http://www.sweetpoison.com/articles/dr-woodrow-monte10.html

  24. Re:It's all about entropy on Distinguishing Encrypted Data From Random Data? · · Score: 3, Informative

    I suggest you read up on cryptography.
    Encryption, in general, is attempting exactly what you're attempting: make plaintext look random.
    What you're trying to defend against is known as a "known-plaintext attack".
    You can use any standard cryptographic approach such as AES-CBC as suggested above.
    For a password-based approach, there are also standard key generation algorithms such as PKCS #5.
    Note that your claim that your approach gives "as random as it gets" data is not true; once you've fixed for all time a set of random numbers, they're no longer "random".
    As for generating random-like numbers deterministically, that's what stream ciphers (e.g. RC4) do.

  25. Re:Le sigh on FCC Fights To Maintain Indecency Policy · · Score: 1

    This is about as believable as the post about DuPont.
    Hemp is still being cultivated commercially. It hasn't revolutionized anything.