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User: Skapare

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  1. Re:440 VAC, to 220 VAC, then to 110 VAC ??? on DC Power Poised To Bring Savings To Datacenters · · Score: 1

    There would be less loss doing a UPS in DC, if the batteries are the same voltage as the system it is protecting. Doing this in the 400VDC to 576VDC range can be done, but it requires specialized personnel just to manage it. Short circuits on 576V batteries can do some spectacular damage. I personally would feel comfortable working on up to 600VAC power circuits, but for DC, that limit would be 48V.

    The generator needs to be considered. It needs to be operating at the same voltage used for the input of the AC to DC conversion, or connected at some point before that. Very large generators (3 MVA range) do come with voltages as high as 13800V. The power system needs to be designed with the transfer switching at some point. This could be done at DC, but that would mean duplicate AC to DC conversion (one for the utility power and a separate one for the generator power). The circuitry doing the utility/battery paralleling could also do a 3rd source from the generator.

    There are many options in the power system design. The proper choice depends on what needs to be optimized for: 1: energy efficiency, 2: reliability of operation, 3: availability of parts, 4: space constraints, 5: management constraints, 6: cost of custom equipment, 7: overall costs, 8: other technical issues (like current harmonics). My big point (among many) is that AC all the way to the rack, if not to the computer itself, is a viable option when done correctly. One simple fact people need to understand is they can power almost every computer (and as far as I know, all server grade computers are this way) with 240VAC directly. Using 120VAC in a large data center shouldn't even be considered for anything but the oddest pieces of equipment that can only handle that voltage. A few 120V outlets would be needed for miscellaneous use availability.

  2. 440 VAC, to 220 VAC, then to 110 VAC ??? on DC Power Poised To Bring Savings To Datacenters · · Score: 2, Interesting

    From TFA:

    The power starts at the utility pad at 16,000 VAC (volts alternating current), then converted to 440 VAC, to 220 VAC, then to 110 VAC before it reaches the UPSes feeding each server rack.

    That's just stupid. I hope it's just a case of a journalist not correctly understanding (which is a common problem). Given the usage of numbers like 220 and 110, instead of the standard 240 and 120, I do suspect it is a journalist giving wrong info. But even many computer people don't know what the standard power voltages are (and have been for decades). Lots of people in the USA still refer (incorrectly) to "two twenty" and "one ten". The standard in Europe is 230 volts.

    With so many conversions taking place, there will be a lot of power loss. To begin with, the computers should have been operated directly on the 240 VAC, not 120. That 240 VAC should have been obtained from the utility power directly (though voltages like 7200, 7620, 7970, 12470, 13200, 13800, 14400, 19920, 22860, 23900, 24940, 34500, etc, are more common ... I've never heard of 16000 being used). Since power comes in as three phase, the ideal voltage conversion would have been 240 VAC line-to-neutral, which would give 416 VAC line-to-line. Neutral harmonics issues can be avoided by use of oversized neutrals or multiwire neutral.

    Do AC wiring correctly, and the advantages of DC are minimal at best. Where the DC plan can have an advantage is that the conversion to 400 VDC, done on a large scale, can be done more efficiently. If that doesn't happen, then it's just one AC-to-DC conversion vs. another AC-to-DC conversion. When the 400 VDC gets to the computers, you still need a PSU to convert the 400 VDC to the various voltages provided to the components inside the computer box (e.g. 12V, 5V, 3.3V, etc).

    AC voltage conversion can be more efficient than 98% when properly designed low impedance transformers are used. That can beat the DC conversions ... even DC-to-DC, in most cases. So you want to do conversion of DC only once or certainly no more than twice.

    It has been reported that mainboards can be designed to efficiently convert 12 VDC to the other voltages needed. Google's original proposal was to supply computers with 12 VDC, allowing them to be manufactured without the PSU entirely, and thus in a smaller footprint as well as having the increased efficiency. The 12 VDC would come from a large PSU in the middle of the rack (to limit the length of wire carrying the higher current that is involved with a low voltage). That large PSU would be designed to accept AC at any voltage from 380 to 480, 50 or 60 Hz, and thus be usable just about everywhere in the world. The PSU may even operate more efficiently when fed with full three phase power (the full cycle nature of three phase power reduces the level of filtering needed for smooth DC).

    Running DC is NOT a crackpot idea. It just needs to be studied correctly, in its various possible forms, and compared to CORRECT designs of AC wiring, in its various possible forms. The choice of 400VDC for distribution within a data center to the individual PSUs is a reasonable one, given that the existing PSU designs go through a conversion to 340VDC to 380VDC, anyway. But these same PSUs, especially in the larger form of one per rack, could just as well be designed to operate from 380 VAC, 400 VAC, 416 VAC, or 480 VAC.

    Maybe DC is the right choice. Or maybe AC can still be the right choice when engineered correctly (which far too often is not done, sometimes due to ignorance, sometimes due to budget limitations which would never go for DC anyway, and sometimes just due to mental inertia).

  3. Re:So, remove DRM? on iTunes DRM-Free Files Contain Personal Info · · Score: 1

    But does it play on Linux with a player such as mplayer ?

  4. What if your email address changes on iTunes DRM-Free Files Contain Personal Info · · Score: 1

    ... because maybe your ISP was partially bought out, and the old owner doesn't allow the new owner to use the domain name?

  5. Re:When I was breaking in on More Than Coding Errors Behind Bad Software · · Score: 5, Insightful

    This is true with any group. There are geniuses and idiots in all groups. The problems exist because once the supply of geniuses have been exhausted, businesses tap into the idiots. And this is made worse when employers want to limit pay across the board based on what the idiots were accepting. Now they are going overseas to tap into cheaper geniuses, which are now running out, and in the mean time, lots of local geniuses have moved on to some other career path because they didn't want to live at the economic level of an idiot.

  6. Re:212,000 more H1B's on Obama Proposes Digital Health Records · · Score: 1

    We need cheap imported labor for everything in this country so we can save money and spent it on cheap imported products.

  7. Already cracked on PowerBeam Demos Wireless Electricity At CES · · Score: 3, Funny

    And it's security has already been cracked. People are ready to get free energy.

  8. Re:Rubbish on Mumbai Police To Enforce Wi-Fi Security · · Score: 1

    There are villages with no running water or sewage, but do have wifi. They are already accustomed to the sanitation issues they have and know how to work around it. But they want access to the net because it means potential economic advancement.

  9. keyloggers via wifi? on Mumbai Police To Enforce Wi-Fi Security · · Score: 1

    How do the keyloggers work via wifi when the terrorist brings along his own EEE or AAO, buys a cup of joe, pays for some wifi access, enters his passphrase to access his data partition, and proceeds to send out all the terror messages?

  10. Re:IT has a higher percentage of whiners on Abused IT Workers Ready To Quit · · Score: 1

    If I was paid the level of the company CEO, then I'd be willing to take the level of stress the CEO has. One big problem with the IT field is the managers (mostly the ones ignorant about IT) are the cause of the problems and the resultant stress. The better jobs I've had were the ones where management respected the IT people (and everyone else that worked for them) instead of trying to use them as scapegoats. In a $60k job I don't want $300k of stress.

  11. IT is the most critical part of the business on Abused IT Workers Ready To Quit · · Score: 1

    So let's hire the least experienced cheapest overseas labor we can find for it and slave drive them to 100 hours a week of work on a shoestring equipment budget and blame them for everything that goes wrong.

  12. Re:Why "scan" the image? on The Technology Behind the Magic Yellow Line · · Score: 2

    Scanning the image lets the computer know the exact pixel for each yardline at various pan, tilt, and zoom points, from which it can then correctly interpolate for all the movements. With enough computer power, scanning the image would be all that is needed and the sensors would be moot.

  13. Calibrating perspective on The Technology Behind the Magic Yellow Line · · Score: 0

    The camera can zoom out to a wide field view and the computer can scan for the yard lines (maybe taking some time as players walk around) to calibrate the perspective. Do it again at a midway and zoomed in position to get the zoom calibration. Thereafter, the pan, tilt, and zoom sensors can guide computer to where to draw the line. And if the yard markers do happen to be in view with high confidence, that can refine the calibration at any time.

  14. Re:So why should my web site use OpenID? on OpenID Fan Club Is Shrinking · · Score: 1

    It means signing in to a site that you have previously signed up for can be simpler. Instead of "remember username and password, or go through reset procedure (involving email and following instructions); enter username and password", it can be "enter OpenID".

    Why can't the browser do this for you? Then you can dump the third party identity provider. And you can have whatever username you want at the new site you sign up to, if no one has taken it before you.

  15. Re:No One Is Asking the Real Question: Why URLS?!? on OpenID Fan Club Is Shrinking · · Score: 1

    It's still goofy. Why the "="? OpenID is still silly relative to a proper login credential management system that could be implemented in browsers, using an encrypted credentials file that could be accessed from a file or a URL, and utilizing a standards based (once standards are made for this) protocol for logging in (HTTPS based).

  16. So why should my web site use OpenID? on OpenID Fan Club Is Shrinking · · Score: 1

    I didn't see this explained on that web page. Why should my web site use OpenID?

    As a user of websites, I also see this as a big problem. How do I get all those various username/password pairs I already have on a few hundred websites tied into OpenID? I do not want to give up the names I have. And to complicate things a bit more, I have more than one on a few of them. How is that handled? And what happens with I visit a new website somewhere and want to be known as Skapare there, too?

    It seems to me that this would all be better done in the client browser, using a standardized means of logging in (which must also always be done via HTTPS). A standardized collection of all your logins for all the websites you visit would be stored in an encrypted file (which you can configure to be anywhere you want it to be on your host system or network shared filespace). When you visit a site that needs a login and you have a login on that site, the web browser will show you the logins you have there (after you have entered the passphrase to open you credentials data file) and allow you to pick one. Then it does the login exchange via a special URL accessed via HTTPS and gets the time limited login hash back from that. When the time runs out on that hash, it repeats this process invisibly (except maybe a little flag somewhere showing it is redoing it). A browser button would exist to re-access the logins for the current site allowing you to switch user or log out. A special code from the web site could also log you out (so the website can make a button to logout from within its visible pages). That code could be a URL like "logout://slashdot.org/" or similar (the mere act of trying to access it engages the logout procedure which operates via HTTPS to actually do the logout) which would be used via a link or a Javascript reload.

    The protocol on this needs to be standardized thoroughly, and vetted by security experts. Then it needs to be made entirely open and free for everyone to use. And it needs to be kept simple (e.g. use the minimum of software so it can be implemented on even the smallest systems in the smallest clients).

  17. Re:Cache? on Why Mirroring Is Not a Backup Solution · · Score: 1

    Did Google cache the user database and passwords?

  18. Microsoft will NOT tank on InfoWorld's Crystal Ball Predicts the Future of Microsoft · · Score: 4, Insightful

    It's still got 10 to 15 years of lingering life in it before it falls.

  19. Re:I would not mind renting the box ... on Comcast Facing Lawsuit Over Set-Top Box Rentals · · Score: 1

    The user interface would not be that hard to do. You press "FAV" and the screen has a big message pop up within 1 second that says "Press number 0 through 9 for which favorite group to use". If only one favorite is even configured, it can skip that and just the one. For configuring, press "MENU" then "FAV" (while in menu). It would present the configuration for favorite number 0, and include a message "to configure a different favorite group, press FAV again then the number 1 through 9". Otherwise it configures the favorite group 0.

    If Joe Sixpack can only understand one favorite set, but would somehow be able to configure it, it can still be the same for him.

  20. Re:I would not mind renting the box ... on Comcast Facing Lawsuit Over Set-Top Box Rentals · · Score: 1

    Unfortunately, the DVR722 also has a major design flaw. It has the ability to receive terrestrial over the air TV in the ATSC (and I think also NTSC) modulation formats. However, it will not perform that function unless the box is activated for the over the satellite local-in-local service. And not all areas have that service available because Dish Network and DirecTV both have not deployed every TV station. Let me know when Dish Network fixes their box.

  21. Re:Suit violates the Sherman Anti-Trust Act? on Comcast Facing Lawsuit Over Set-Top Box Rentals · · Score: 2, Insightful

    If your idea of a free market is a company can arbitrarily discriminate against customers, then I don't want to get your idea of free market at all. And where monopolies exist, there is no freedom. I'm more in the the "fair market" system, if you need a name for it.

  22. Re:I live in Vermont and have Fairpoint on Fairpoint Pledges To Violate Net Neutrality · · Score: 1

    The customer is the 1st party. The internet provider (Verizon, Fairpoint) is the 2nd party. The email hoster (Yahoo!, AOL, MSN) are the 3rd party. Maybe the 2nd and 3rd need to be switched. From what I understand, Verizon provided a web site with their branding (but maybe outsourced to another party to actually run it and host it) that allowed access to email with the Yahoo!, AOL, or MSN names because not everyone wanted @verizon.net. That's basically what I mean by 3rd party.

    I don't believe Fairpoint would block access to the Yahoo!, AOL, or MSN web sites, including their email sites. If they do, it would be amazingly stupid. I think someone just got all twisted in a knot because they thought they were going to be blocked from accessing the Verizon web site their email had been on for years, and forced to use Fairpoint. Now, if they had an email address like newsreporter@verizon.net and have to change it (because Verizon is not their provider), then I can understand them getting into a tizzy. But they don't seem to have facts organized (even if they are right).

  23. Re:I live in Vermont and have Fairpoint on Fairpoint Pledges To Violate Net Neutrality · · Score: 3, Interesting

    Yahoo!, AOL and MSN or Other Third-Party Portal Users

    On Jan 31, 2009, you'll still have access to Yahoo!, AOL, and MSN content, but you'll no longer be able to access your email directly through the third-party portal. Instead, you'll now have access to the new MyFairPoint.net portal.

    If you were using the VERIZON third-party portal to access your email that is located at Yahoo!, AOL and/or MSN ... since you are no longer a customer of VERIZON, and instead are now a customer of FAIRPOINT, third-party access mechanism is now through FAIRPOINT's service. In other words, Fairpoint is going to be providing a similar kind of service that Verizon did.

    I'm sure there will be problems for people with email addresses "@verizon.net". There should not be problems for people using other email addresses. I see nothing in this that says people cannot go to Yahoo!, AOL, or MSN directly for email address originally established through those providers (e.g. youremailaddress@aol.com). If such email accounts were previously restricted such that they could ONLY be accessed via the VERIZON web site, I could understand them being similarly restricted to the FAIRPOINT website. But as for people having their email addresses changed, I can't see that affecting anyone other than those who have an "@verizon.net" address.

  24. Re:Suit violates the Sherman Anti-Trust Act? on Comcast Facing Lawsuit Over Set-Top Box Rentals · · Score: 2, Interesting

    To the extent that any agreement between the cable provider and the manufacturer prevents the sale of the box directly to the public, there is a violation going on. Comcast is not in the business of selling hardware, so they should not be required to do the selling. But they must not be allowed to interfere with the selling of such boxes by any means. The manufacturer must sell them to anyone willing to buy in the minimum quantity they will sell (e.g. at least as many as the smallest cable company has bought), and Comcast must allow them to work on their system at the same pricing structure, minus the rental costs. That doesn't mean Joe Consumer gets to walk in to the cable company office and buy one, or the manufacturer office and buy one. But if a retailer wants to make a bulk purchase of these from the manufacturer, the manufacturer must sell them at the same pricing and quantities they sell to cable companies, and the cable companies that support this box technology on their systems must allow them to work (if they are Cable-Card based, then they must support it, but if they rent the same box, they must support the purchased ones, too).

    Personally, I'd rather rent ... especially considering the failure rates going on (at least half my neighbors have had to get them replaced at least once). However, the boxes Comcast offers are a piece of shit ... so we need some kind of

  25. I would not mind renting the box ... on Comcast Facing Lawsuit Over Set-Top Box Rentals · · Score: 4, Interesting

    ... if it weren't such a piece of shit.

    1. Only one channel favorite set. The Comcast piece of shit box only has ONE set of favorite channels. I would actually use as many as FOUR of them just for myself (for different viewing moods). My brother and father each would probably use 2 or 3. It needs to have at least 9 or 10 channel favorites. This is NOT a hard feature to code and it takes very little flash memory to save.
    2. Video conversion modes. Programs come in a variety of video modes, both standard aspect and widescreen. The output mode setting does not always convert right for all program sources. And its very hard to change the video output mode and it kills any recording you were doing just to change the mode (because it requires a full power cycle, not just the "off" function, to get the menu to make the change).

    Comcast needs to demand that their box manufacturer let a real geek program the box and shoot the managers (though I would really much more prefer that they suffer a horrible lingering painful death) that try to interfere.