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User: jeffb+(2.718)

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  1. Power companies need to think bigger. on Six Electric Cars Can Power an Office Building · · Score: 1

    Take an autonomous-driving system with enough of the bugs worked out. Put it in a semi cab, pulling a trailer full of batteries. Build fleets of them.

    Every morning, they filter into the city, tethering themselves to various load-transfer facilities. All through the day, they help to level out demand peaks.

    At night, they filter out, and flock around whatever generating plants are hardest to throttle up and down -- hydro, nuke, whatever -- and refill themselves.

    What battery price/performance levels would we have to hit to make this more attractive than building more peak capacity and power lines? Would it ever make sense to do it this way, instead of having static battery farms (and additional line capacity into the city)?

  2. Re:Science is not the problem on Physicist Peter Higgs: No University Would Employ Me Today · · Score: 1

    So, you're saying that any test I can do extremely well on, without also going on to have an extremely successful research career, is no true exam?

    Tell me, would the exams you have in mind have a section covering common rhetorical fallacies?

  3. Oh, it's a lot older than that. on Simulations Back Up Theory That Universe Is a Hologram · · Score: 3, Interesting
  4. Re:Microbes require hundreds of Myrs to evolve on Mars Rover Curiosity Finds Ancient Lakebed · · Score: 4, Interesting

    I suppose the assumption is that, if there was one habitable environment that persisted for tens or hundreds of kiloyears, there were probably others. I also suppose that life would be more likely to maintain its foothold in an environment where lakes tended to persist for many years, as opposed to appearing and disappearing with the seasons.

  5. I know! Let's send email to show our support. on Employee Morale Is Suffering At the NSA · · Score: 1

    Address it to: ...well, if we want the NSA to see it, I guess it really doesn't matter who it's addressed to, does it?

  6. Re: Slight change in title, if I may on Nobody Builds Reactors For Fun Anymore · · Score: 3, Interesting

    Start with nearly anything along the lines of "Chemical Magic".

    I remember spending many happy hours looking through the "experiments" for making nitrogen triiodide, various preparations with white phosphorus, carbon tetrachloride-carbon disulfide mixes with the same index of refraction as glass (dump a broken glass into a tank of the stuff, REACH IN WITH YOUR HAND, and pull out a whole one -- magic!), lots of mixes with potassium chlorate and/or red phosphorus, lumps of sodium or potassium -- you get the picture. For a few brief, wonderful years, I was able to order some of these chemicals through my elementary or middle schools, and occasionally find them in some old out-of-the-way pharmacy.

    I still resent the crackdown on chemicals, but if you'd offered me-the-kid a choice between the old-school chemical buffet and today's Internet, I would've leapt for the keyboard in a heartbeat.

  7. Re:Science is not the problem on Physicist Peter Higgs: No University Would Employ Me Today · · Score: 2

    From primary school all the way through college, my mutant ability was to do superhumanly well on tests. I tended to place somewhere in the top tenth-percentile (99.9%). My grades were good, but not that good -- I didn't do very well at straight memorization, and I didn't have much drive to do well on larger projects. I met a few others who tended to score exceptionally well on tests, and I saw that this pattern was pretty common.

    The current system is broken, for reasons described in the summary and in some of the posts here. But I'm pretty sure difficult exams wouldn't do what you think they'd do.

  8. Proposing to do this in live humans is nuts. on First Images of a Heart Injected With Liquid Metal · · Score: 1

    They can't be serious about anything except getting press attention. Gallium is sticky, not all that unreactive, and immiscible with water-based fluids. So, when you inject it, it displaces blood (thus cutting off oxygen to the tissues it perfuses), it gets lodged wherever it goes, and it almost certainly leaches into the surrounding fluids fairly swiftly as chloride ions and oxidizing species attack it. And ionic gallium isn't that non-toxic, as I recall.

  9. Re:Gallium = Sticky on First Images of a Heart Injected With Liquid Metal · · Score: 1

    Yep. Between the stickiness, the quick formation of an oxide "skin", and the expense, it's not nearly as much fun as mercury. Mercury really is a wonder material -- it's just a darn shame about that cumulative neurotoxicity.

    So, for liquid metals, so far we have:

    Mercury -- low-melting, extremely dense, fairly cheap, fairly unreactive, high surface tension/nonwetting, but with a high vapor pressure and serious toxicity issues

    Gallium-indium alloys -- somewhat low-melting, medium density, very low vapor pressure and low toxicity, but quite expensive, kind of reactive, and sticky

    Sodium-potassium alloys -- somewhat low-melting (down to dry-ice temps if you add cesium), very low density, very low vapor pressure, potentially not too expensive (if you avoid the cesium), but a bit of a reactivity problem (put them in contact with anything containing water, and you won't have to worry about low temperatures any more)

    Wood's metal and the like -- cheap and dense, but quite toxic (most require cadmium), and not very low-melting

    All other metals -- just get them hot enough, which is usually too hot for what you have in mind

    We just need to evolve so that we can tolerate ambient temps around 800K. Lots of things get easier at that point.

  10. Re:His taxes paid for the electricity on EV Owner Arrested Over 5 Cents Worth of Electricity From School's Outlet · · Score: 1

    His taxes also already paid for all the computer equipment in the school, so perhaps he should've walked right out with that, too. Or at least made off with all the playground equipment, since it was "intentionally installed outside".

    You have an odd understanding of "public property".

  11. Re:Going to change everything on Andy Rubin Is Heading a Secret Robotics Project At Google · · Score: 5, Insightful

    Seriously, what is our long term goal as humans?

    Oh, I don't know -- maybe not having to spend half our waking hours, for over half our lives, doing something that we'd rather not be doing, except that we'll be homeless and starving otherwise?

    Sure, there are some of us lucky enough to get paid for doing what we'd choose to do anyway. There are even a lot of us who would make terribly unwise choices about what to do with our time if we didn't have to work for a living. But if we have a grand refactoring that separates "earning a living" from "having a career", I'm not sure it's necessarily a catastrophe.

  12. Perjury! Piracy! What? on Hotfile Settles With MPAA, Drops Countersuit Against Warner Bros · · Score: 3, Interesting

    So, after winning the right to use an incendiary term in trial, and blocking their opponents from using another incendiary term, Hotfile... rolled over?

  13. Re:Another brainiac VP heard from on The Desktop Is Dead, Long Live the Desktop! · · Score: 1

    Sorry, you've got the wrong guy.

    Sall is quite sharp, and if you'd stoop to the level of "content consumer" long enough to RTFA, you'd see that he's still doing development. He interviewed me (very informally) many years ago, and we got into a bit of an argument about memory-management strategies. He was certainly better informed than most managers, and indeed better informed than many of the developers I was interviewing around the same era.

  14. Re:Going to change everything on Andy Rubin Is Heading a Secret Robotics Project At Google · · Score: 1

    And displacing electronics manufacturing workers will have what effect on US unemployment, again? As opposed to unemployment in, say, Singapore, China, Malaysia, where electronics manufacturing has moved over the last few decades?

  15. Re:Heavy Wheel - 12 _lbs._ on Patent Battle May Loom Over 'Copenhagen Wheel' Electric Bike · · Score: 1

    Give me a nice enough power assist, and I'll drag that boat anchor up that hill faster than your hard-trained legs can haul even the state-of-the-art carbon-fiber wisp of your dreams.

    Seriously, what difference does 12 extra pounds make? If you've got power assist to accelerate it and lug it up hills, and regenerative braking to stop or descend with it, it's more or less a wash in terms of energy use. Sure, there are losses, but it's nothing like just hauling the extra weight with your muscles. I guess you'd lose a little stopping power, but with the weight centered at the rear axle, you'd gain some traction as well.

    And, of course, nobody's proposing to allow this in competitions.

  16. Re:Why Bother? on Patent Battle May Loom Over 'Copenhagen Wheel' Electric Bike · · Score: 4, Interesting

    Your response illuminates one benefit called out in the article. With a wheel like this, instead of violating the law on descents, you can regeneratively brake, and then use that energy to stay close to the speed limit on ascents as well.

    I bike for fitness, and I fully intend to get something like this one day. I may be looking for an all-electronic drive train, where my cadence and effort are coupled to speed and torque only as a long-term average -- I decide how hard I want to work and what pace I want to maintain, and the power system manages everything else, letting me know if my configuration will either draw my battery down too far or exceed its charging capacity. No more finicky derailleurs, no more chain cleaning, no more chewed-up cuffs or shoelaces. And if the regenerative braking is good, it doesn't really matter that the bike is heavier -- you reclaim energy when coming to a stop, and then tap that energy to accelerate back to your pace.

    But who am I kidding? I'm riding a 30-year-old touring bike. I've put 10K miles on it over the last four years, and I'm still on the original chain, never mind groups and such. I'm not going to be pushing the leading edge (except perhaps with obscenely bright headlights).

  17. Beautiful to the eyes, but what about the ears? on Ask Slashdot: Recommendations For Beautiful Network Cable Trays? · · Score: 3, Informative

    "My company prides itself on an office environment that follows a modern design aesthetic: open floor plan, bold colors on the walls, cool lamps in the corners."

    I'm happy for you that your office is pretty. But where do you go when you need to stop "collaborating" and get some actual work done? Or when the group at the bench across from yours is "collaborating" so loudly that your group can't hear each other talk?

    Open floor plans may be great for some jobs, but they are poison for work that requires concentration, especially when that work also entails remote collaboration. If you find this isn't true, I'd like to hear more -- especially about how you handle conference-call participation when there's a loud discussion nearby.

    (Yeah, I know I'll take an "off-topic" hit to my karma for this. Sorry; it's a hot button at the moment.)

  18. Re:Escape from the Solar System? on Comet ISON Survives Perihelion (Barely) · · Score: 1

    I've got almost no intuition at these scales, but nudging a cometary nucleus by a few m/s seems like it would take a lot of energy -- maybe more than the processes acting on this comet are likely to generate.

    Now, nudging one chunk at the expense of the others is a different question. When a comet fragments, how quickly do the pieces typically separate? If the nucleus splits, forcing chunks apart at tens of m/s, the ones forced along track might get the boost they need -- but I don't know within an order of magnitude how fast the chunks are likely to be separating. Anybody?

  19. Obvious prior art... on Google Wants To Write Your Social Media Responses For You · · Score: 4, Funny

    Possible response:

    • yes/no
    • or what?
    • go away
    • please come back later
    • fuck you, asshole
    • fuck you
  20. Yes, please tell where the market will go next. on Nasdaq 4000 — This Time It's Different? · · Score: 3, Informative

    ...but don't tell everyone, just me.

    If you can predict its future behavior, it's not a market. "Technical analysis" is today's astrology, and like yesterday's astrology, it works only so long as you're surrounded by believers.

    That said, there are ways to reliably outperform the market:

    • 1. Buy better (faster, lower-latency) access than your competitors.
    • 2. Buy more regulators and legislators than your competitors.
    • 3. Cheat, without getting caught -- or without regard for getting caught, if you've done a good job at point 2.

    I've got money in the market, because in general it outperforms other investments over the time horizon I'm facing. But I don't delude myself that I can outrun the pack.

  21. Sungrazer Twitter feed -- a useful source on Comet ISON Approaches Perihelion · · Score: 3, Informative

    I've never been much of a Twitter fan, but this feed has been excellent for links to timely information and discussion:

    SungrazerComets on Twitter

  22. Re:Cost vs. Benefits on Ask Slashdot: Best Laptops For Fans Of Pre-Retina MacBook Pro? · · Score: 1

    Sure, a given memory technology's prices bottom out and then rise again as new generations come out. It irks me that upgrading my late-2008 MacBooks (now used by the kids) to 6GB would require two 4GB modules at nearly $100 each. But when those machines were new, 4GB modules were not available, period, and when they came out a year or two later they were over a grand. I would've been nuts to max them out early, even if I now wish I'd bought the modules at $60 or whatever the minimum was.

  23. Re:Cost vs. Benefits on Ask Slashdot: Best Laptops For Fans Of Pre-Retina MacBook Pro? · · Score: 1

    I'm skeptical about repairability, at least home repairability -- but as long as the cost of, and demand for, RAM and disk continue on their current trajectories, buying what you need now and upgrading over time makes a lot more sense than buying now for your needs two or three years down the road.

    I bought a 2011 MBP 17" partly because I wanted the larger screen, but largely for upgradeability. I put 16GB of RAM in it for under $100 (although I see prices have gone up since then). I've deferred putting in an SSD, because I expect to get 512GB or 1TB for not much more than a 128GB unit would've cost me at purchase time.

  24. Re:Rats. It won't QUITE fit on a microSD card... on Have 100GB Free? Host Your Own Copy of Wikipedia, With Images · · Score: 2

    Yeah, I was misremembering the line:

    "The British Museum and Library, as digitized and databased by the Chinese Informagical Coalition. The haptics and artifact data are lo-res, to make it all fit on one data card. But the library section is twenty times as big as what Max Huertas sucked out of UCSD. Leaving aside things that never got into a library, that's essentially the record of humanity up through 2000. The whole premodern world."

    128PB, 97% in use.

  25. Rats. It won't QUITE fit on a microSD card... on Have 100GB Free? Host Your Own Copy of Wikipedia, With Images · · Score: 1

    ...yet. But I guess most phones won't easily read sqlite databases yet, either. I suppose it won't kill me to lug around a full-sized SD card.

    Still looking forward to the library-of-Congress-on-a-card from Rainbows End.