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User: jbengt

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  1. Re:Already been done in China for a while on Sharp Announces Sales of DC Powered Air Conditioner, Other Products To Follow · · Score: 1

    I don't know about building codes . . .

    That's obvious.
    Most building, electrical, mechanical, etc. codes require certain products to be tested by a nationally recognized testing agency, of which UL is commonly named in the code. (BTW CSA and UL are largely interchangeable these days, as they cross-list many, if not all, of the products tested by one or the other.)

  2. Re:Why not both? on Sharp Announces Sales of DC Powered Air Conditioner, Other Products To Follow · · Score: 1

    Generally, you are right. But an inverter 93% efficient at full power is likely much less efficient during low power operation. I've seen UPS literature (UPSs are basically AC to DC to AC converters with batteries included) where the total heat dissipation at 20%+/- load was greater than the heat dissipation at 100% load, let alone the efficiency.

  3. Re:Why not both? on Sharp Announces Sales of DC Powered Air Conditioner, Other Products To Follow · · Score: 1

    It is brilliant.

    Variable frequency AC inverters are nothing new (I've been specifying those for large HVAC systems since the late '80s/early '90s), they're just starting to get cheap enough to be used in low-capacity products like these. The only thing new is the possibility of having DC power available as the source, instead of 50 Hz or 60 Hz AC.

  4. Re:Why not both? on Sharp Announces Sales of DC Powered Air Conditioner, Other Products To Follow · · Score: 1

    Just a question, wouldn't builld-up of static electricity be a problem for high voltage DC?

  5. Re:Why not both? on Sharp Announces Sales of DC Powered Air Conditioner, Other Products To Follow · · Score: 1

    For smaller HPs, Electronically Commutated DC motors are becoming common where you want to vary speed and torque. But for larger motors (more than 1 HP), Variable Frequency Drives (AC to AC conversion) driving 3-phase induction motors are more practical and very common.

  6. Re:Why not both? on Sharp Announces Sales of DC Powered Air Conditioner, Other Products To Follow · · Score: 1

    True, but the trend for small, single phase motors is to use Electronically Commutated DC motors, converting the AC to DC and then using fast switching power transistors to drive the DC motor directly at whatever speed you want. The issue with using solar power would be that the solar cell DC voltage is lower than needed and varies. There would need to be a standard DC voltage established, and, in addition to putting the solar cells is series to achieve that, you may have to use DC to DC conversions to maintain a constant voltage (though, I guess, it wouldn't have to be exaclty constant, just within parameters req'd by the motor - still you need to standardize on those tolerances before you could see commercially useful adoption of DC in the home and office)

  7. Re:Where in the US Constitution..... on Clinton Promises 500 Million New Solar Panels · · Score: 1

    The Congress shall have Power To lay and collect Taxes, Duties, Imposts and Excises, to pay the Debts . . .
    To borrow Money on the credit of the United States;
    To regulate Commerce with foreign Nations, and among the several States, and with the Indian Tribes;
    To make all Laws which shall be necessary and proper for carrying into Execution the foregoing Powers, and all other Powers vested by this Constitution in the Government of the United States, or in any Department or Officer thereof;
    No Money shall be drawn from the Treasury, but in Consequence of Appropriations made by Law; and a regular Statement and Account of the Receipts and Expenditures of all public Money shall be published from time to time.

  8. Re:A plea to fuck off. on A Plea For Websites To Stop Blocking Password Managers · · Score: 1

    It's risk analysis.

    Using a password manager sounds like a guarantee that at some time in the future access to all the passwords will be lost simultaneously. Writing them down physically, there is a better chance of recovering them, and very little chance of some random hacker finding them.

  9. Re:No surprised in good ole Mass... on Massachusetts Examining Disability Access For Uber, Lyft · · Score: 1

    If this is a service that is needed by people, then it should be provided by government, and not forced upon private enterprises. Towns and cities themselves should operate transport for the disabled

    Towns and cities, those that have public transportation, already have accessible transport for the disabled. Why should the private companies that serve the public be allowed to pick and choose those who they want to serve?
    The "government" (the feds) simply legislated that businesses cannot discriminate against the disabled, then issued guidelines on how to do that to hopefully reduce the number of lawsuits about it. And local & state governments do have to abide by those guidelines, too, not just the private sector.
    While I think that some interpretations of the guidelines can be unreasonable as applied (e.g. adding elevators can be really expensive in existing buildings) most are good for everyone, including the business, and relatively inexpensive.

  10. Re:Wait a minute... on Microsoft To Cut 7,800 More Jobs, Take $7.6 Billion Writedown On Nokia · · Score: 2

    $7.2B indeed.
    http://www.reuters.com/article... [reuters.com]
    They've valued nokia below their total worth estimated at acquisition time.

    And it looks like MS shareholders had already devalued MS for it.

    (Tue Sep 3, 2013 7:16pm EDT)
    Shares in Microsoft slid as much as 6 percent in the afternoon, lopping more than $15 billion off the company's market value, as investors protested the acquisition of an underperforming and marginalized corporation that lost more than $4 billion in 2012.

  11. Re:Energy Storage? on Facebook's New Data Center To Be Powered Entirely By Renewables · · Score: 1

    I gather from the scant information in TFA that they are not actually using green energy, except as an accounting gimmick to pay for energy from the wind farm that is connected to the whole grid.

    TFA says: "For sustainability, the Fort Worth data center will be cooled using outdoor air rather than energy-intensive air conditioners, thanks to technology it pioneered in its Oregon location."
    Fort Worth summer cooling design temperature is typically figured well over 100F, with wet bulb temperatures approaching 80F on cooler days in the low 90s, and they're going to "cool" the data center with that air. Something's missing from TFA.

  12. Re:Methamphetamines age you prematurely. on Scientists Show Human Aging Rates Vary Widely · · Score: 1

    I don't buy it. My older brother never had kids, never got married, and was balding and grey by the time he was thirty. I have a wife and three adult children and still have (almost) all my hair and a lot of it not yet grey. My younger brother has gone through a divorce and has grandkids, and a stressful job; he's has a little less hair and it's a little greyer, but he runs a couple of miles a day and is in great shape (much better than me).
    Stress can contribute to aging, but it doesn't seal your fate.

  13. Re:trick them into it ... on Ask Slashdot: How Do You Find Jobs That Offer Working From Home? · · Score: 1

    Tried that (I did have an actual job offer)
    I got one day a week work-from-home, then got laid off two years later in the recession (I made it through the first two rounds of layoffs, though.)

  14. Re:In short? on Ask Slashdot: How Do You Find Jobs That Offer Working From Home? · · Score: 1

    . . . you waste 723 hours in your car every year. Even at the minimum wage, that's $5241.75 in opportunity costs that you're losing every year. You could do so much with that 723 hours: you could learn a new skill . . . , you could take up a hobby, . . . , you could even sleep more . . .

    Which is why I take the train. (Not the original poster)

  15. Re:"as a Service" = you have to buy it Every Year? on First Windows 10 RTM Candidate Appears · · Score: 1

    . . . there will be no more windows 'versions', that this will just be in place updates from this point.

    So, they will update the one true version forever? I don't think so.
    They will have to differentiate versions in order to sell new ones, or they'd just be giving away their services for free. Or they could, you know, move to a subscription service model.

  16. Re:Microsoft is not trustworthy for a rolling rele on First Windows 10 RTM Candidate Appears · · Score: 1

    Mac can't run most games. Windows is the best option for most people.

    That's a flagrant non sequitur to me.

  17. Re:Need to be adjustable on Ask Slashdot: Have You Tried a Standing Desk? · · Score: 1

    Use fixed standing desk with a drafting stool.

    Historically, this has been the best for me. It allows you to shift from standing to sitting and back, which is much more comfortable in the long run than either standing or sitting. I worked this way at a drafting desk the first 14 years or so of my career, but unfortunately it's no longer an option, as employers want to squeeze everyone into small spaces with standard furniture to stare at computer screens all day.

  18. Re:adjective choice on Struggling University of Phoenix Lays Off 900 · · Score: 1

    I do not believe that most colleges have endowments "in the billions". Many have less than one billion.

  19. Re:imperial = fagot on 3D Printed Supercar Chassis Unveiled · · Score: 3, Interesting

    As an American who routinely has to use feet, inches, fractions of an inch, square feet, square inches, cubic feet, gallons, lbs force, lbs mass, ounces mass, watts, kilowatts, horsepower, btuh, boiler horsepower, square feet EDR, psi, feet of water, inches of water, inches of mercury, mm of mercury, atmospheres, etc., converting back and forth within the customary US units is a pain in the ass, no matter what you say. Converting to metric, doing the math, then converting back can sometimes be easier.

  20. Re:Trabant was light too on 3D Printed Supercar Chassis Unveiled · · Score: 2

    . . . parts that are eagle to congenitally made parts . . .

    Let me guess, you're using voice recognition software?

  21. Re:Phase out fossil-fueled power plants by midcent on The Presidential Candidate With a Plan To Run the US On 100% Clean Energy · · Score: 3, Informative

    You are correct, except in your definition of a Ponzi scheme. Simply paying people out of current receipts is not a Ponzi scheme. A Ponzi scheme involves creating the illusion of high returns on investment by paying out the capital from new investors and calling it profit on the old investments while claiming that all of the original investments are still there. The difference is that Social Security does not claim you have any capital invested nor that you are making any profit - it has always been portrayed as paying current retirees from a tax on current workers (albeit, with some money put aside to smooth out the highs and lows caused by the employment and retirement numbers). The numbers can deceive people about the federal budget deficit, but it is not a Ponzi scheme by Social Security.

  22. Re:Phase out fossil-fueled power plants by midcent on The Presidential Candidate With a Plan To Run the US On 100% Clean Energy · · Score: 3, Insightful

    Of course that should all still be dwarfed by the social security budget, and in that, not just social security to elderly.

    Actually, until very recently, the Social Security budget was running in the black and contributing to the ability of the US government to spend. Unfortunately, all of the Social Security surplus was invested, in accordance with the law, in US Treasury bonds, and those debts were not counted as part of the federal budget deficits. So the problem is not in the Social Security budget, per se, but in Congress having already spent all of the Social Security surpluses of the past.

  23. Re:Oh no... you mean... on Political Polls Become Less Reliable As We Head Into 2016 Presidential Election · · Score: 1

    It wasn't some media poll leading up to the election. It was election-day results from the eastern states, where the polls had already closed, and exit-polls from the western states, where polls were still open. Many people decided not vote after work since Reagan had already been declared the victor before their polling places closed.
    Actual election results come in a lot faster now than they did in the '50s.

  24. Re: Whats wrong with US society on Privately Owned Armored Trucks Raise Eyebrows After Dallas Attack · · Score: 1

    TheIr gunowners are actually a well regulated militia.

  25. Re:Challenges... on SpaceX Wants Permission To Test Satellite Internet · · Score: 1

    I'm assuming that there would also be the latency between the end user and the ground antennae using terrestrial copper and fiber, otherwise this would be a mostly one-way internet. I doubt the individual would have the power to upload a fast stream directly to the satellite.