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User: Ungrounded+Lightning

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  1. Re:Alternate solution: High-efficiency communicati on New Paper Offers Additional Reasoning for Fermi's Paradox · · Score: 2, Informative

    Except for RADAR. Maybe RADAR will be replaced too, but for now it's quite noticeable.

    It's also highly directional and mostly in frequency bands that don't make it through the ionosphere all that well.

    RADAR is already migrating from simple continuous streams of short high-energy pulses to broad chrips and other, more complex signals that give more information about the target (and have less power demand on the transmitter).

    Aircraft location for air traffic control is migrating from RADAR to aircraft-mounted GPS beacons. (The RADAR will still be around for a while. But don't be surprised if it migrates to more subtle technology.)

    Military RADAR has a big advantage if it looks like background noise to a target.

    (Marine radar does NOT - it's really good if your little sailing yacht makes a big spot on the screen of the supertanker that could run you down - a spot indistinguishable from that of another supertanker. B-) But marine radar is low power.)

    Short high-energy pulses chew up a lot of valuable communication spectrum. Moving to a lower-energy signal could make it more available for other uses, creating an incentive to migrate.

    So don't be surprised if even RADAR eventually fades into the background.

  2. Re:Alternate solution: High-efficiency communicati on New Paper Offers Additional Reasoning for Fermi's Paradox · · Score: 2, Informative

    It might be "noise", but it's still a distinct power band - not a black body distribution at all.

    But it's a very broad band - and there are many of them. The amount of power needed depends on how far you want to go and what the background is that you need to surpass - and a major component of the background is thermal noise, pushing toward a thermal distribution of signals as well.

    Yes the distribution is distinguishable - at least so far. But remember that you have to observe the signal in the presence of other backgrounds as well. (A narrow band filter like you can use to find an AM or FM signal just won't cut it.) How far away from the Earth can you make that distinction? And if scientists DO, would they attribute it to intelligent signal transmissions or look for some oddball physical process - in the emitter or the medium?

  3. So now RSI is good for the environment? on RITI Printer Uses Your Coffee Grounds For Eco Ink · · Score: 2, Insightful

    Seems to me the treatment of the Repetitive Stress Injuries incurred from operating this device would more than offset any environmental gains.

    There are motors in printers for a reason.

  4. Alternate solution: High-efficiency communication on New Paper Offers Additional Reasoning for Fermi's Paradox · · Score: 5, Interesting

    The calculation of 1000 years seems a bit too long. We can't figure out how to shorten it because we don't know how long we're going to be using broadcast signal based communication as opposed to some other more direct means.

    My own contribution to the debate:

    As technology advances the limited amount of available bandwidth becomes more valuable, while costs of utilizing it drop. The civilization migrates its bandwidth use from simple, extremely redundant, coding schemes (like AM and FM) to subtle, highly-efficient schemes that are virtually indistinguishable from thermal noise (like OFDM). They also use spacial multiplexing to re-use the same bandwidth over and over at various locations. This buries the few redundant parts of the signal (like the pilot subchannels used for synchronizing the receiver) in interfering noise.

    The result is that, after a fairly short time, at a distance they are virtually indistinguishable from a hot black body - and lost in the sagans of other hot things in the galaxy.

    Our first AM voice radio broadcast was at the end of 1906. 102 years later we're taking a big step in the transition to OFDM-or-CDMA-everywhere by shutting down "analog TV" and replacing it with OFDM-based digital. AM and FM are already using digital variants to squeeze more out of their spectrum. Any bets on how long until they switch, too?

    Once the simple-modulation blowtorches are switched over the few remaining detectably-patterned signals will be soft voices crying in a wilderness of high-noise-floor. If we don't DELIBERATELY send some intended-to-be-noticed beacons we'll again be lost in the background - our own and the galaxy's.

    A thousand years? In our case the detectability sphere looks to be only a tad over 100 years deep.

    Don't blink!

  5. Re:Typo? on Stanford's Quantum Hologram Sets Storage Record · · Score: 1

    Ah. Thanks for the catch.

  6. Typo? on Stanford's Quantum Hologram Sets Storage Record · · Score: 1

    there's a typo in your sig.

    Really? The "spell" command agrees with all the words except "Weimar" and that's the correct spelling. (It's a German city name, so it hasn't been sufficiently incorporated into American English to count as a word for spell checkers.)

  7. Re:They did... how much?? on Stanford's Quantum Hologram Sets Storage Record · · Score: 5, Insightful

    If I understand holography and what they're doing correctly (and I DID work as a tech in Emmett Leith's lab so I have some clue), they're transforming the information.

    Yes, each electron has information from 35 bits. But more than one electron has that same information, encoded differently. How many storage electrons do they need to encode it in a way that is recoverable?

    The information per electron is the total information encoded divided by the total number of electrons needed to encode it at a high enough resolution to be recovered.

    Also: The illustration of the way they're encoding it looks like it's not just electrons that encode it, but also their absence. Add in HOLES to the count of "things encoding the bits".

    I'll be surprised if the total comes out to more than one bit per electron site. (Note that they may get more than one such site per atom.)

  8. Sometimes it is good. on Less Is Moore · · Score: 1

    Continually making the same thing for less money is not a very good business model.

    Sometimes it is a good model. If you can achieve adequate margins and sell a lot more of it, you end up making more money.

    When supercomputer-level power cost multiple millions, only a few sold. Now it costs dollars (in the form of GPU chips in video adapters) and a LOT of those are sold. Which makes more money for the manufacturers?

    This is encoded in a snappy saying:

    "Fast nickels are better than slow dimes."

  9. Because renting costs time. on Progress On Electric Cars · · Score: 1

    And don't give me "rent one when you need one", either

    Why not?

    Because renting costs something more precious than money: Vacation time.

    It costs it in the time consumed to rent, pick up, refuel, and drop off the car.

    And it costs it in risk: That the car won't be there, won't operate properly or will break down, will be unsuitable, poorly cleaned, etc. When it's your car these are under your control. When it's an agency's car it's under theirs. (Even if the failure probabilities are the same the aggravation level is higher when a rented car fails.)

    Vacation time is precious. Typical workers get two weeks of vacation and fifty of work - so multiply the daily pay by 25 to get a cost estimate. Subjective quality-of-life losses from shaving the vacation to rent the car may be higher.

    Quality of life suffers in other ways, too. Like the weekenders you might take if you can just throw the bags in the car and go, which you won't if you have to deal with Avis or Hertz.

    I could go on. But the point is that the "rent it when you need more range" so-called "solution" has unacceptable costs for some consumers.

    And the OTHER point is that, if it can meet a few simple performance targets, a plug-in hybrid COULD completely replace the passenger car for many users - and thus be a big market winner. But the manufacturers, so far, are wearing their "commuter" and "eco-nut" blinders, building low-range, low performance, flat-terrain cars, and not yet aiming for those targets.

  10. So how does it handle ... on Toward Autonomous Unmanned Aircraft Technology · · Score: 1

    ... collision avoidance? And air traffic control interface?

    Taking off, flying GPS waypoints, and landing, are a lot easier if you're the only thing in the sky and can do anything you want.

  11. Re:Why is this new? on Toward Autonomous Unmanned Aircraft Technology · · Score: 1

    Now we are making planes smart, to duplicate the ability of cruise-missile.

    So when will it get a warhead?

    Who needs a warhead when the plane has nearly-full tanks of jet fuel and enough velocity and hot parts to light it off when it hits?

    The 9/11 crews proved this. You can see the second twin-towers plane bank at the last moment so the fuel-filled wings puncture, flood, and light several consecutive stories - and the holes show the first one did the same. This lit enough stories of fire (and provided air holes to keep it from suffocating) that they eventually heat-weakened enough of the cross-bracing structure to collapse the buildings.

    Think "rough equivalent of a planeload of napalm".

  12. Re:Energy storage on Progress On Electric Cars · · Score: 1

    Lithium batteries are too expensive, take too long to charge, don't have a high enough energy density, and don't last long enough.

    There have been a couple breakthroughs in Lithium cells that address all of that. The new ultra-fast-charge cells are already in production for use in buses and this should get the price down, production up, and bugs out very quickly. If nothing goes wrong they should be good and cheap enough for passenger cars within a couple more years.

    If the current work on ultracapacitors pans out ...

    Ultracapacitors have the problem of voltage variation with state-of-charge which complicates the drive electronics. And IMHO they're likely to ALWAYS lose to batteries on energy-to-weight ratio. (Though I'd LOVE to be proven wrong on energy density. The electronics thing is soluble and capacitors can handle a LOT of very fast and deep cycles.)

  13. "Most journeys" aren't enough. on Progress On Electric Cars · · Score: 1

    Most journeys that people really need their cars for are less than 50km, going to the shops and commuting.

    And if you buy a car for "most journeys" that doesn't handle "all journeys" you need to buy, license, insure, and maintain TWO cars. The costs are obvious and I won't even START on the environmental impact of that. (And don't give me "rent one when you need one", either.)

    If the electric/hybrid is to REPLACE the fuel-only auto it needs to be able to handle the daily commute, the shopping trips, the entertainment trips, and the vacations.

    Call me when you get one that can do the Silicon Valley commute and weekend shopping trips on batteries only, runs hybrid on ski trips to Tahoe and weekends in Reno (scavenging a couple thousand feet of altitude downhill energy for use uphill like a hybrid scavenges stops for starts), and goes all-day cross-country on the flat with mileage at LEAST as good as a gasoline-only car and distance between fillups ditto. THEN you're ready for prime-time.

  14. Re:Clearwire's competitors supported the delay on Senate Approves 4-Month Delay In Digital TV Switch · · Score: 1

    I'm not alleging this. (At least not in THIS response. B-) )

    The question was why somebody else added a corruption tag and I was suggesting that these allegations may be the reason.

    If Verizon is for it then perhaps they're having trouble with their own rollout and would like THEIR competition (other than Clearwire) to be delayed, too.

    So until everybody who bought TV bandwidth comes out in favor of the delay I'm prepared to entertain the idea that the delay may be the administration playing favorites. But I have absolutely no evidence that this is what is happening.

  15. Because of Clearwire vs. LTV carriers. on Senate Approves 4-Month Delay In Digital TV Switch · · Score: 3, Informative

    Not trolling but honestly, why was this article flagged as corruption?

    Because Obama's adviser on the DTV transition was an executive VP at Clearwire, which (with Sprint) is rolling out a WiMAX network. The competition (notably Verizon) is about to roll out LTE on the bandwidth being freed by the DTV transition (which they bought at auction for billions.)

    Delaying the DTV transition for months delays the LTE rollout ditto, while Clearwire captures more market share and the competitors' capital is locked up in useless assets that are producing no revenue.

    See this slashdot article for more.

  16. Looks like Clearwire paid the bigger bribe. B-) on Senate Approves 4-Month Delay In Digital TV Switch · · Score: 1, Interesting

    As was previously posted on slashdot, Obama's chief advisor on the DTV transition was a Clearwire executive.

    Clearwire, in cooperation with Sprint, is currently rolling out its WiMAX network. It faces competition from vendors attempting to rollout the competing LTE standard - on the TV bandwidth to be freed up by the DTV transition (for which they've already paid the government billions of bux in bandwidth auctions).

    Delaying the transition delays the LTE rollouts - which both allows Clearwire to grab more market share and delays revenue from their investments to the LTE carriers.

    Looks like Chicago politics has gone national. B-)

    = = = =

    PS: For those who are talking about forced purchase of converter boxes as an "economic stimulus": It's NOTHING compared to the LTE rollout that is on hold, locking up capital and creating huge opportunity costs.

  17. COLORblind? How about BLIND blind? on Building a Better CAPTCHA · · Score: 5, Interesting

    The idea is that humans are better at image recognition that computers, but humans can legitimately disagree on their interpretations and some humans are color blind.

    COLOR blind? Some humans are BLIND blind. Others have various vision or vision processing impairments that would make meatware-visual-coprocessor-test CAPTCHAs reject them.

    IMHO most CAPTCHAs are already and obviously violating of the Americans with Disabilities Act. So now, in the info-war between weapons and armor (which weapons always win anyhow), even more of us less-than-Aryan-Supermen become collateral damage.

    Dogs are (allegedly) color blind and "... on the Internet nobody can tell you're a dog!". Well, maybe PEOPLE can't. But now the web applications can. B-(

    The solution to being attacked by better weapons is not better armor. That's only a stopgap. The solution is to hunt down those who misuse weapons and make them incapable of or unwilling to continue.

  18. Re:Don't want to pay on 2/3 of Americans Without Broadband Don't Want It · · Score: 0, Flamebait

    We must give them gawd as soon as possible even if they claim they don't want it. It's for their own good!"

    Replace "gawd" with "broadband" and you have a politician and/or slashdotter.

    Or with "heroin" and you have a pusher.

    Or with "Marx and Lenin" and you have a "neighborhood organizer".

    (See Leslie Fish' song _Trinity_ "... but who will come and save you from your Lord?")

  19. Re:And this differes from other countries how? on KY Appeals Court Nixes Seizure of Gambling-Linked Domains · · Score: 2, Interesting

    Looks like someone flunked american history or government. The states aren't countries. The commonwealths like Mass or VA aren't countries either.

    As originally envisioned, the states were supposed to do most of the governing, except for things that are international or inter-state, but the states are not countries.

    I agree that someone flunked but I doubt it was yours truly.

    Note that the first 13 states PREDATE both the Continental Congress and the Federal Government which succeeded it (though "staged a coup on it" is arguably a valid description). So they clearly were sovereign entities which eventually surrendered certain functions to the federation they formed.

    Later states were sometimes formed from territories controlled by the federation (Michigan, Ohio, ...) and sometimes (Texas, Hawaii ...) independent (for some value of independent) countries admitted by treaty. However: All later states are admitted on equal basis with the original states. So if they weren't independent countries that joined a federation BEFORE they became member states they became such BY BECOMING member states. (Note that they have to be republics to be members and that one of the Constitutional functions of the Fed is to insure that they continue to be republics internally.)

  20. IMHO it's not THAT cut and dried. on KY Appeals Court Nixes Seizure of Gambling-Linked Domains · · Score: 1

    [The 11th Amendment] is generally interpreted to mean states have immunity from suits from out-of-state citizens and foreigners not living within the state borders.

    I was under the impression it meant that, if a citizen of another state or foreign country wanted to sue (on civil issues) a state government it had to do so in that state's courts (or perhaps in the courts of a state where the act in question was committed and the defendant state had some "presence", i.e. assets worth seizing).

    Of course the state, once sued in its own courts, might elect to assert its sovereign immunity. But it also might not - or it might already have laws on its books waiving the sovereign immunity in a range of cases that included the issue at hand.

    Alternatively: The state and its officials might be vulnerable in federal court under the federal civil rights law for "violating (the plantiff's) civil rights under color of law".

  21. No it's not. It's an entry in a database. on KY Appeals Court Nixes Seizure of Gambling-Linked Domains · · Score: 3, Interesting

    But it's an odd thing when you think about it. A domain name is really just that. The name of a domain.

    "What's in a name?"

    In this case it's NOT just a name. It's an entry in a publicly-accessible and trusted database, mapping the name to a set of servers.

    THAT's what the state of Kentucky seized.

    And it's very valuable. I'm waiting with bated breath for the suits demanding reimbursement for lost (legal!) revenue resulting from the disruption of their business (along with damage to their trademark) caused by Kentucky's successful appropriation of their domain records.

  22. And this differes from other countries how? on KY Appeals Court Nixes Seizure of Gambling-Linked Domains · · Score: 3, Interesting

    I love how each state thinks it is pretty much the only thing in existence and the rest of the world can play by it's rules.

    And how does this differ from other countries - like China, Russia, England, ...?

    Remember: "States" - and Indian Tribes - in the United States are separate countries. The States just happened to join a federation for dealing with other countries - a federation like Common Europe, NATO, the UN, the League of Nations, etc.

    (And of course the federation has progressively encroached on the States' sovereignty ever since, eroding the safeguards intended to retard such behavior. That's exactly what was expected at the time. But it's also a separate issue.)

  23. Vans were certainly possible - and trivial. on Pandora Trying Out Invasive Commercial Breaks · · Score: 2, Informative

    From what I've heard the detector vans were an urban myth.

    While I can't state authoritatively whether the vans were a myth, the technology was real. Also simple and cheap.

    Television and radio receivers of the era were all superheterodyne - down-converting a signal to a low and standard "intermediate frequency" ("IF"), where a fix-tuned amplifier/filter combination did most of the boosting and rejection of out-of-band signals before the detector stage. (Fixed-tuned filters are easier than variable-tuned and filter selectivity is in terms of a percentage of center frequency so lower frequencies are easier to band-pass filter than higher.)

    The down-conversion was done by "mixing" (multiplying, or using other non-linear approximations) the incoming signal with a sine wave at a frequency from a "local oscillator" ("LO"), displaced from the signal of interest by the IF frequency. (Yes I know "IF frequency" is redundant.)

    This "mixer" stage is preceded by a small number (one or two) of variable-tuned amplifier stages - which reject the other "image" (incoming signals on the "other side" of the local oscillator frequency) and to provide SOME attenuation of the local oscillator energy in the mixer as it "leaks" toward the antenna. The isolation is enough to keep the local oscillator frequency from radiating enough energy (through the antenna or out through the box or other wiring) to jam other channels - but far too little to keep it from being trivially detectable by a radio tuned to (or sweeping across) its frequency.

    So it's trivial to put a "panoramic" (sweeping) receiver in a van, with a directional antenna on the roof, and hunt down the local oscillator radiation of any receiver that is operating and tuned to a BBC channel.

    This technology predates the TV tax. It was used in WWII (at least by the Germans and probably by the British as well) to hunt down receivers tuned to the enemy's news outlets (which carried embedded messages to embedded spies) and "numbers stations" (which carried encrypted messages ditto).

    They do now us a database to work out who hasn't bought a license, and then knock on the door now and again to check up on you.

    Much simpler in an era of cheap computing and document copying. But more intrusive. Detection is STILL possible and cheap. So I'd be surprised if they knocked on the door before checking to see if there was a receiver running.

  24. Re:Photovoltaics aren't yet up to breakeven... on Intel Testing Solar Power For Data Centers · · Score: 3, Insightful

    By the way: "Breakeven" in this context is "costs no more than installing and buying grid power" - appropriately amortized over the life of the installation.

  25. Photovoltaics aren't yet up to breakeven... on Intel Testing Solar Power For Data Centers · · Score: 3, Informative

    ... but solar thermal -> heat engine has, if the size is reasonably large.

    Wind turbines ditto if large enough and the site has good winds. (For house-sized they're only past cost breakeven if you can save a few grand by not running grid power to a new rural site.)

    Progress in photovoltaic design and energy storage systems may bring both solar and small wind past the competitive-with-grid crossover, perhaps in the next few years. Rises in grid power costs could do it, too.