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User: Ungrounded+Lightning

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  1. Re:Spent $1,000 on incandescents thanks to this la on US Light Bulb Phase-Out's Next Step Begins Next Month · · Score: 1

    The light temperature is off for the wood interior. We had it the way we want it and intend to keep it that way.

    The TEMPERATURE is too high, too. (Halogens last long because the gas reacts with the evaporated tungsten that's landed on the inside of the capsule - picking it up as a tungsten halide, then depositing it as tungsten metal again at the hottest - i.e. thinnest - part of the filament.)

  2. Even without taking them away we're lower. on How the Lessons of Columbine Saved Lives At Arapahoe High School · · Score: 1

    Take away the crimes of two inner city subcultures from the statistics and then the murder and violent crime rates are the same as Europe.

    Actually we're lower even without that. It turns out there's a BIG difference in how crimes are reported - especially vs. Great Britain. For instance:

    In the US we count a murder when there's a body and suspicious circumstances. In Great Britain they count a murder when they have a CONVICTION.

    In the US, if a gang robs an apartment house it's one robbery per unit. In GB it's one robbery.

    In the US if daddy comes home and shoots his wife, three kids, and himself, it's four murders and one suicide. In Japan it's five suicides.

    This kind of stuff goes on and on...

    One thing that's not in question:
      - People of European ancestry have a lower vicitmization rate in the US than in Europe.
      - People of African ancestry have a lower victimization rate in the US than in Africa.
      - People of Asian ancestry have a lower victimization rate in the US than in Asia.
    And so on.

  3. Oops. Had that confused. on No Longer "Noble"; Argon Compound Found In Space · · Score: 1

    Did a little checking. It's Xenon that they were playing with back then. Xenon is reasonably easy to convince to make covalent bonds, and some of its compounds are used industrially and available in commercial quantities.

    Argon is less reactive, and they didn't get it to form compounds until 2000, with some encouragement from an ultraviolet light source to kick an electron up to another level.

  4. Nothing new about argon compounds. on No Longer "Noble"; Argon Compound Found In Space · · Score: 1

    Argon forms compounds without too much coercion. Back in the mid '60s chemists were playing with them regularly. As I understand it (I'm NOT a chemist and haven't done this myself):

    Just mix argon and fuourine in a pressure vessel and heat it up. (VERY CAREFULLY! Fluorine gas is deadly!) You'll quickly get copious amounts of argon difluoride, tetrafluoride, and even some hexafluoride. These are stable enough to stick around once you bring things down to room temperatures.

    Once you've got them, there are techniques for substituting other stuff for one or more of the fluorines.

    But you DO have to be careful, even after the fluorine is out of the picture. I hear these compounds tend to be explosive, due to argon's propensity for dumping the riders and flying away alone.

  5. Should have been writting in terms of efficiecy. on US Light Bulb Phase-Out's Next Step Begins Next Month · · Score: 1

    IMHO the regulations (if the government felt it NECESSARY to regulate) should have been written in terms of minimal efficiency, not banning certain types of light source.

    There are two technologies I'm aware of that produce an incandescent that's about as efficient as a CFL. They're pricier than the highly competitive commodity bulb. But with an efficiency floor taking those out of the running, these might have become competitive.

    The first is quite a few decades old: You make a substantially spherical bulb and put the filiment at the center. Then you coat the bulb with an interference coating that reflects most of the infrared but passes most of the visible light. The small percentage of energy that forms visible photons escapes, while the bulk that forms infrared photons are returned to the filament, reheating it and having another chance to be re-radiated in the visible.

    The second is recent: A nanotextured surface for the filament. It radiates almost entirely in the visible wavelengths (much like an antenna tuned to a band of frequencies, which it launches well while bouncing other bands back toward the transmitter).

  6. Spent $1,000 on incandescents thanks to this law. on US Light Bulb Phase-Out's Next Step Begins Next Month · · Score: 1

    My wife has meniere's disease, which results in debilitating vertigo attacks. At this point the balance sensors in one of her ears are essentially totally destroyed, and those in the other are slowly degrading.

    One of the results is that her vision is now a much bigger part of here balance system. Anything that disrupts it can trigger vertigo attacks.

    The flickering of arc lamps and many fluorescent lights causes these attacks. (For instance, she can't spend more than about 20 minutes total in a "warehouse store" such as Costco, Lowe's, Home Depot, etc. because of their use of arc lights (with substantial regions of the store on a single phase). We have to turn off the tube-style kitchen lights

    120 Hz flicker is well above the "flicker fusion rate", so you can't perceive it. We believe the attacks occur because the strobing causes slight delays and errors in the apparent position of objects when they are, or she is, moving.

    Some compact fluorescents trigger attacks, some do not. (We believe this to be because, on those that don't phosphor persistence or adequate filter capacitors after the rectifiers "fill in" the "valleys" of the post-rectifier waveform, reducing flicker until it's not a problem, while cheaper lights skimp on capacitors, allowing the light to strobe.)

    LEDs are good for flicker rates into the GHz. Some of those we have examined flicker quite dramatically. So we will be very cagey about switching to them, until they're both efficient AND the manufacturers have begun making a practice of supplying enough capacitor filtering to avoid significant flicker.

    Incandescents, of course, don't have the issue. They heat up and cool down very slowly "filling in the valleys" just fine.

    When this regulation came along, though, we were concerned that we would soon be unable to purchase replacements for burned out incandescents in our Nevada home, which would have been a serious health problem if non-flickering replacements were not available.

    So we purchased enough current production bulbs for each of the fixtures to last for the remainder of our expected lifespans.

    This cost about a thousand bucks, so far. (We still need to buy the replacements for the "can" fixtures over one of the minor countertops, and some more "daylight" ceiling fan bulbs. Probably another $400 by the time we're done.)

    We really didn't want to do this, preferring to buy replacements as needed and switching to LEDs in about another three years IF flicker-free devices become available. But the new regulation created enough of a risk to force us into it.

    Now that we've bought them, we'll probably continue to use them long after we'd have switched to LEDs.

    So in our case the unintended consequences were quite the opposite of what was intended.

  7. Re:Yes it IS how PON (Passive Optical Networks) wo on ITU Standardizes 1Gbps Over Copper, But Services Won't Come Until 2015 · · Score: 1

    A pair of light frequencies (one outgoing, one incoming)

    I don't believe! It will mean that either there are 250 lasers of different color and [lots more junk].

    You're thinking of a different scheme: Wavelength division multiplexing. That would be about as expensive as separate fibers to each house with individual transcievers. (Moreso, since the many different-colored laser transcievers are pricey.) Wavelength division multiplexing is about getting more bandwidth or channels out of fibers, in long-haul or around large datacenters.

    There aren't 250 frequencies in PON. There are only two. One for signals from the curbside box to ALL 250 houses, one for ALL the houses toward the curbside box. (The system I'm familiar with used the two common infrared laser diode frequences, which are far apart to easily filter.) They only use two colors so they don't have to worry about reflections from imperfect fiber joints and the like, and so the subscriber boxes don't have to sort out each others "talking", too.

    Single transceiver in the curbside box for ALL the 250 subscriber sites. That's where the big savings from PON comes from. (There's a bit more by using one fiber for all and splitters, rather than separate fibers for each.)

    The houses are sorted out by time division multiplexing, not separate color lasers.

  8. Re:Electric cars are impressive power houses on Six Electric Cars Can Power an Office Building · · Score: 1

    Or to put it another way how little energy most things need. You don't need tons of power unless you're trying to heat somewhere or move heavy things.

    There's a hysterical amount of power in mechanical motion. One horsepower is almost exactly 3/4 of a kilowatt.

    Cruising a mid-size car at highway speed against air and rolling resistance takes about 18 HP (much more for accelerating or hill-climbing, of course), while a "typical home" load is about a kilowatt average, i.e. 1 1/3 HP.

  9. Not so much for lithium ion batteries. on Six Electric Cars Can Power an Office Building · · Score: 1

    Not to mention the well-known fact that batteries have a limited number of discharge/recharge cycles

    That depends on the battery chemistry.

    As I understand it, modern Lithium Ion chemistries are mainly affected by time since manufacture / first charge (due to ongoing electrode oxidation) and high temperatures, with extra cycling (if it doesn't result in overheating the battery) a minor issue.

    (But I'm not expert on this so maybe somebody who is could comment?)

  10. "Vectoring" is about canceling crosstalk. on ITU Standardizes 1Gbps Over Copper, But Services Won't Come Until 2015 · · Score: 1

    Crosstalk alone I would think would be an issue.

    Yes, it is. The standard is largely about canceling crosstalk. (Look for "vectoring" in TFA.)

    Without the standard's crosstalk cancellation feature, but with everything else according to the standard, the speed drops by a factor of five.

    200Mbps over these short hauls is not to sneeze at. But it's not such a big deal, either.

  11. Yes it IS how PON (Passive Optical Networks) work on ITU Standardizes 1Gbps Over Copper, But Services Won't Come Until 2015 · · Score: 1

    Ya no... that's not how it works at all.
    It's called a Fiber Mux: http://en.wikipedia.org/wiki/Multiplexing

    That's how things like DSLAMs work: One (or more for redundancy) fat pipe for backhaul, a router or switch in the box at the curb, and individual links carrying only each customers' data to the DSL modem at each customers' site.

    Passive Optical Networks work like cable internet (and vaugely like the original party-line coaxial Ethernet): A pair of light frequencies (one outgoing, one incoming) connect the box at the curb, through attenuator/splitters, to each of a handful of sites. (The one I saw had an 8-bit hardware address and handled 250 subscribers per fiber.)
      - The outgoing signal contains the traffic for all up-to-250 subscribers on a given link and the subscriber box rejects traffic for all but its own destination(s).
      - The incoming traffic takes turns on the other light frequency. (Timing information is on the outgoing link and they run a link-level protocol to assign slots as requested when the subscribers' boxes have traffic, rather than a collision/retry protocol.)
    Advantage is you need about half as many optic transcievers to implement it, while optical splitter/combiners are really cheap.

    So, yes, it would be trivial to build a box that could listen to the fiber and tap your neighbors' downbound traffic. (You MIGHT be able to tap the upbound traffic from SOME of your neighbors, too, with a sufficiently sensitive optic receiver and if the fiber joints and splitter/combiners have enough discontinuity to reflect enough of their inbound light.)

  12. Better than burnout. on New Ford Mustang May Have Electronic "Burnout" Button · · Score: 2

    Burnouts may be showy. But you get better acceleration from a standing start if you DON'T break traction.

    What I'd find more useful is a "button" for automatic maximum-traction acceleration (to a presetable speed or until you let off the gas). Think "anti-lock brakes" but in acceleration.

    (Though what I'd find FAR more useful is integrating "tow-haul" mode with the speed control.)

  13. Re:War Engines on Why Engineers Must Consider the Ethical Implications of Their Work · · Score: 1

    In the context of WWII, the atomic bomb undoubtedly created a net savings of both allied and Japanese lives.

    But you really don't want to debate this in a Sushi bar.

  14. Re:War Engines on Why Engineers Must Consider the Ethical Implications of Their Work · · Score: 4, Interesting

    it wasn't just Germany developing atomic weapons, Japan was as well

    Among their plans was one to dirty-bomb the US west coast, San Francisco in particular.

    They also understood the potential for a fission bomb and were working on it. This is why they recognized the A-bomb right away.

    That's also why it was important to bomb Nagasaki the week after Hiroshima. This discredited the generals' claim that making these things was hard and the US couldn't have very many of them. Dropping two in as many weeks raised the spectre of one a week forever.

    And the generals were right. As I understand it, the US had one in the pipeline and enough material for one or two more. Then there'd have been a several month pause, followed by about one a month.

    This dearth of material, combined with the fact that the first one dropped was an untested design so failure WAS an option, was why there wasn't a demo to try to convince the Japanese to knuckle under without an actual bombing. The less-than-a-handful were too precious to be spent on other than actual targets.

  15. And half a dozen people .... on Ask Slashdot: Why Are Tech Job Requirements So Specific? · · Score: 1

    We usually still end up needing to sift through 40-50 resumes and end up interviewing 4-6 people (over the phone or on-site) ...

    Read this to my wife, who responded: "Thank you for wasting my time."

    You may have hundreds or thousands of people who wasted a minute reading the ad. You have 40-50 (possibly out-of-work) people who wasted maybe 10 minutes and a buck or two sending you a resume, or an hour composing a cover letter. You have a half-dozen who spent hours, and maybe auto expenses, coming to and attending your interview, and experienced hours of stress responding to your people's questions. You wasted maybe a day of their time in the midst of a job hunt. All when you had a candidate you were happy with.

    Did you EVER hire anybody except the one you'd started with? Or did you just get a warm fuzzy feeling from having found some possible alternates in case he drives into an overpass pillar during some night's commute?

    But thank you for your honesty. Job hunters really need to understand the viewpoint from the other side of the desk. It will help them accept the repeated rejections that result from such "fair hiring" practices.

  16. Re:To hire specific people on Ask Slashdot: Why Are Tech Job Requirements So Specific? · · Score: 2

    Slight problems with your theory:

    It wasn't the poster's theory. It was what the professor told the class.

    It's also been well documented. Recruiting firms have seminars for their customers on how to do it, and videos have been smuggled out by irate HR people and posted to the internet, sent to congresscritters, ...

    One, it happens in countries that don't have H1-Bs.

    Even countries that don't have H1Bs - or companies that operate there - often have requirements that job openings must be posted openly and the most qualified candidate(s) be offered the job. The same procedure works when an administrator has a particular candidate (or relative) he wants to hire, and HR procedures require the posting be open, for whatever reason.

    Two, unless these H1-Bs are coming from Gallifrey there's no way they have 279 years experience in Java 147 on RHEL DCXLIV.

    That sounds like another hiring pathology, which has caused much hilarity in the past, the result of clueless hiring managers and HR departments.

    Back when Unix was first becoming broadly used in private companies, want ads were filled with job offers for low-level unix sysadmin positions - all requiring experience with Unix and its tools that could only be met - if at all - by Ken Thompson, Dennis Ritchie, M. D. McIlroy, and J. F. Ossanna. B-)

    On the other hand, H1-B candidates often have their qualifications "boosted" on the resumes presented by the recruiting agencies representing them. (Often the candidates themselves have no idea this is being done - and are horrified if they discover it.) They may be enhanced beyond real-word possibility, either because those doing the enhancement are as clueless as in the Unix ads case, or because it's a way to insure that no read candidate can meet them (without also lying on the resume).

  17. When you INSTALL it? on The Burning Bridges of Ubuntu · · Score: 1

    You have the right idea, big time. But IMHO you didn't go quite far enough.

    Ubuntu should follow the openSUSE way: when you install it, it asks you which desktop you want.

    The screen server and all its friends get restarted when your session is launched at log in. There's no reason the system can't run the desktop of each user's current preference, and give him the opportunity to change that preference - for the session or persistently - every time he logs in.

    IMHO It should be a drop-down menu opton on the login, with a well-documented and easy way both for the user to edit his settings and for an admin (or even the user, in his own account) to add more desktop software.

    The install - actually, the new-account create - would just ask about the acconts' initial preference.

    Heck: It REALLY should ALSO be an item on the background pulldown menu, or equivalent, of every windowng system to switch mid-session. But there are a lot more worms in that can, starting with convincing the developers of all the windowing systems to provide a hook for users to drop their baby and adopt children of their rivals.)

  18. That doesn't follow at all. on CyanogenMod Installer Removed From Google Play Store · · Score: 1

    Note from the article "Removed reference to Google stating the app was not in violation of TOS â" this was a mischaracterization of Googleâ(TM)s statement."

    Well presumably if they removed that statement because it was a mischaracterization of what Google said, then Google said it was in violation of the ToS.

    That doesn't follow at all. You're engaging in "The Falacy of the Excluded Middle."

    There's an enormous difference between Google saying that installing the app isn't a TOS violation (thus committing themselves to supporting the phone) and claiming it is.

    For instance, they could be reserving the right to make the claim later, on a case-by-case basis depending on what was installed and/or how it was done. Or they could just be avoiding potential legal entanglements without extensive (and expensive) study and/or risk of litigation if their lawyers guessed wrong about how juries, judges, and regulatory agencies around the world might act.

  19. Also, they're posting "return to factory" images. on CyanogenMod Installer Removed From Google Play Store · · Score: 2

    Actually, that rule changed a few weeks ago: ...

    From the article:
      - They are also retroactively reinstating the warranties of people who already asked for an unlock code and had their warranty voided as a result.
      - They are posting "return to factory images". (Nice pun, that. They let you flash your phone back to the factory image, which you'll want to do before returning it to the factory for service.)

    I guess losing a touch more than a third of a billion dollars ($342 million) in one year CAN sometimes get executives to look at customer complaints and try to address them. B-)

  20. Re:I hope the laptop shell's monitor is LED. on Dual-Core Allwinner A20 Powered EOMA-68 Engineering Card Available · · Score: 1

    I've had a number of laptops where the CPU was doing just fine but the monitor died due to fluorescent lamp end-of-life.

    So, um. Why didn't you just, uh, you know, fix them?

    Because they belonged to my, um, employer, who by then had handed me a later model for my primary machine.

    I've only had one of my own die so far, and it wasn't the screen backlight that failed.

    I intend to pop that one open and see if it is something simple, like a loose connection. But it was one of two identical ones I bought used for like $50 or less, and had already run for me for two years. So I swapped the disk into the other one and I'm not in a big hurry.

    One nice thing about Linux: It runs just fine on older hardware, as long as you don't need the extra crunch of a new model for some application. (Better, even, since the driver guys have had time to figure out the peripherals.)

  21. Maybe the charge jcreeping deeper into the crypt? on Tesla Model S Has Bizarre 'Vampire-Like' Thirst For Electricity At Night · · Score: 1

    TFA says exactly where the power goes: the car's electronics don't sleep when the car is off.

    So the next question is: Is the fix only partial, leaving a lot of stuff still awake? Or is there something else? It looks to me like his measurement of the leakage and vampire load has a methodology problem.

    I note that the test performed by the author would find another "drain": Charge diffusion in the batteries.

    When a battery is first charged the surfaces of the electrodes become fully charged, but the bulk of the plates are still not quite full. As the charge carriers diffuse deeper into the material, the cell still has the same charge (except for leakage, which is a separate issue). But the surfaces become less charged as the core comes up to match them. (This is why the last stage of charging is slow - to get MOST of this done before charging cuts off.)

    This is a BIG DEAL on lead-acid batteries. I'm not sure how much of this effect is present in lithiums, which is what Tesla uses, but I bet it's lower but not zero. (I note that my cellphone does both bulk and "topping" charging of its lithium batteries - ramping up quickly to the 80% level and then trickling its way up to "100%".)

    So if he's running his car in the day, charging it until it hits 80% in the evening, unplugging it overnight, and plugging it back in, I bet that, even in the absence of ANY leakage, the charge controller will see the lower voltage as the cells from surface charge diffusion as the battery not being quite at the 80% setpoint. So it will "top them off" to the setpoint level again. If the computation for the display doesn't take this into account it will look like a lost of charge.

    He should:
      - Leave it on the charger for several days, not driving it (while the whole bulk of the cell material reaches equilibrium), then
      - Unplug it overnight, and
      - Plug it in in the morning.
    Then he'll be measuring just the leakage - from the cells and any vampire loads.

  22. Re:Vampire? Huh?! on Tesla Model S Has Bizarre 'Vampire-Like' Thirst For Electricity At Night · · Score: 1

    Again, I love it when non-engineers talk out of their ass.

    It's fun when engineers do it too. B-)

    They all need current clamps which are just one side of a transformer coil to step that current down into a usable range.

    Transformer-type current clamps won't measure DC.

    You need either a (powered) hall-effect sensor type clamp or one where the magnetic field directly moves a mechanical needle. Those are a lot harder to find.

  23. I hope the laptop shell's monitor is LED. on Dual-Core Allwinner A20 Powered EOMA-68 Engineering Card Available · · Score: 1

    I've had a number of laptops where the CPU was doing just fine but the monitor died due to fluorescent lamp end-of-life.

  24. Re:Now if only it could TRANSMIT. B-) on Tapping Data From Radio-Controlled Bus Stop Displays · · Score: 1

    The dongle receivers are typically I/Q receivers.

    Yes, I understand that. I guess I phrased it ambiguously.

    What I meant is "convert data from the USB to I/Q OUTPUT, i.e. do the TRANSMIT side of a transceiver, too, not convert the receive side to I/Q from something else.

    Then we need a local oscillator and mixer to boost it back UP to the desired frequency band (which might be done with the companion block downconverter chip if the appropriate signals are accessible or if it is actually also a transciever chip). Add a "power" amplifier (for suitably small values of "power"), a diplexer (if you really need to use a single antenna for both directions) and you're done.

  25. (Supposedly) Broken for only some buses on Tapping Data From Radio-Controlled Bus Stop Displays · · Score: 1

    One of the cited article talks about the system having two cases:
      - The buses with the tracking hardware are displayed based on the tracking.
      - the buses without the tracking hardware are displayed based on the schedule.

    Now maybe the line you're on has buses without tracking. (Or maybe the tracking system doesn't work and it's all a crock.) But the anecdote that your particular line is just showing an automated schedule doesn't show that all others are doing the same.