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Comment: Re:Help me out here a little... (Score 1, Interesting) 206

by Chris Katko (#49505073) Attached to: Utilities Battle Homeowners Over Solar Power
There's a couple of issues. But I'm not a power systems engineer, so chime in if you are one.

If the control systems make the assumption that power will always be net positive--all work will be going in always and any fluctuations will still be overwhelmed by the amount of current indraw--then those meters, and the control station could have problems.

Think of it this way. Your power supply has a current source limit. It rarely publishes the current SINK limit. So if you plugged your 12-volt supply into your 5-volt supply (to get 12-5=7 volts) the 12-volt line would be sourcing, but instead of common, the 5-volt line would be sinking. The sink limit for a typical power supply voltage rail is MUCH smaller. You can have a 5 A rail that can only take a few milliamps of INPUT current. The key thing here is, power supplys typically have a direction.

For a more IT analogy, think about cable service. Cable comes from head end, hits distribution nodes, and then more nodes, and then finally the end node and to your house. Each one of those makes an assumption that you're not going to broadcast cable (not internet, but TV) from your house.

Second, end-node measurement. Power meters don't have to be designed to measure current both ways. That's an assumption made during manufacture. If you bought one of those nifty Kill-A-Watt meters and then ran current backwards, it would likely either not register it, OR register it still going forward. That's a serious problem for a power company. They can see reduced load using their existing system, they cannot see negative loads.

It's possible I'm wrong and they're great future thinkers or need negative power measurement as part of some sort of power systems. But I've not heard of it, so a Power Sys engineer chime in.

Moving along, let's be honest: Just because someone makes something does not mean it's compatible with the grid. You don't run one-off kernel drivers made by your neighbors. If someone hacks together some random garage equipment (and not some government certified power controller box) and plugs it into the grid, that grid is now touching everyone else's house nearby. Imagine water coming into your house, and all a sudden some guy in your neighborhood is pumping his well water back into your system. Would you want to drink that? Now clearly the stakes are a little less dangerous with electricity, but that guy can still muck up the line. He can add tons of noise to it, he can raise or lower the voltage level until the system can react--and if his changes faster than the system can react, it's not going away. I wonder if it's even possible that someone could use a system like that to "game" the correction system into swinging harder and damaging your components.

More on compatibility, it's not just current and voltage. There's power factor. There's noise. There's the shape of the power wave to begin with. (Also called noise.) Someone dumping square waves at the right voltage and current into your power line is going to cause problems. It's kind of like someone buying an Arduino and bit-blasting ethernet frames into a hub (Layer 1). Everyone shares those physical lines and if that Arduino doesn't do it exactly right, everyone's got problems.

The point with all of this scribble is that power grids are very specific and allowing anyone to plug in and generate power is like allowing anyone of your neighbors to share your water. If they're not careful, or don't even care, to match the requirements of the system, they can easily wreck havoc with it and you.

I am not even remotely saying it should be illegal to generate power. What I am saying is it should be very clear what the requirements of the grid are, and that anyone who violates those requirements should be fined, and repeat offenders kicked off the grid. I also think generators/controllers should be certified to work with the grid if they're not already.

Comment: We all need to realize... (Score 5, Insightful) 125

by Chris Katko (#49492179) Attached to: AMD Withdraws From High-Density Server Business
...we need AMD. Because if AMD goes away, Intel has zero competitors in the x86/64 market. Most people here probably aren't old enough to remember that CPU's used to cost an arm-and-a-leg in margins, and then when a bunch of hot shots like the 6502 came out, prices dropped literally over night. How could they drop so much? Because it was nothing but margin to begin with.

If AMD goes the way of the dodo bird, so do our cheap processors. Moreover, we'll likely lose a great deal of software freedom as what Intel says becomes law across the whole board. UEFI and TPM? Disneyland to what Intel can demand under the guise of "security" from every future computer.

Comment: Re:0.6? Are you serious? (Score 1) 213

by Chris Katko (#49490211) Attached to: GNU Hurd 0.6 Released
To be fair, they know it's not going to replace the Linux kernel now, so it's merely an experimental project. Much like many of the Microsoft experimental kernels, except those eventually are put to death and the relevant guts are sucked into the next revision of Windows. (see Singularity OS--an OS that does away with hardware virtual memory and the translation lookaside buffer)

Comment: Perhaps this is obligatory but... (Score 2) 142

by Chris Katko (#49489523) Attached to: How do your actual ISP speeds compare to the advertised speed?
"Fuck Comcast."

Every time the weather gets bad, their connection goes to shit. It doesn't matter if I'm at home, or 30 miles away on their "Business Class" internet at work. It cuts out over and over and Comcast doesn't give two craps about fixing it.

Try working from home in IT on a connection that drops every couple minutes. It's incredibly frustrating--even moreso when I looked at the ridiculous prices they charge me every month.

Comment: Re:How Did We Get Here? (Score 4, Informative) 231

by Chris Katko (#49485093) Attached to: Can Online Reporting System Help Prevent Sexual Assaults On Campus?
"Rape culture" isn't really about solving any problems. It's about generating fear to generate money and votes.

Rape rates have been falling drastically since the 70's.
http://1.bp.blogspot.com/_ZlRN...

Rape rates on colleges are LOWER than outside of college:
http://upload.wikimedia.org/wi...

And rape rates in some other 1st-world countries are HUGELY higher--but nobody here cares apparently:
http://upload.wikimedia.org/wi...

But none of these facts comply with the myth of the "oppressive white male" who thinks he can rape and take whatever he wants.

Nobody disagrees with the idea that rape is a bad thing. But people are willing to hijack that axiom to create hysteria and generate political power.

Comment: Re:How is this really news? (Score 5, Informative) 309

by Chris Katko (#49480303) Attached to: NVIDIA's New GPUs Are Very Open-Source Unfriendly
>Why sould a GPU manufacturer spend a lot of time supporting such a small user base

I don't know, maybe because most super computers on the fucking planet use GPUs? Why would scientists want a GPU manufacturer to support the operating system they do most of their work on? Oh, I can't think of a reason.

Meanwhile, we're trying to do some work in ROS. I certainly don't want CUDA cores to help speed up the processing and filtering of tens of thousands of LIDAR points. Nor could I possibly use shaders for anything outside of gaming.

This much sarcasm is killing me. Please get better opinions before I die.

Comment: Re:Jack Thompson is a piece of shit (Score 2, Insightful) 118

by Chris Katko (#49479709) Attached to: Jack Thompson Will Be Featured In BBC Film 'Grand Theft Auto'
Anita isn't the problem. It's all of the morons who take her seriously. Why? Because people want to believe that we live in a world where all women are oppressed. And once you subscribe to that narrative, you're going to read anything that anyone says that supports that ideology of victimization.

And news companies know their audience is a bunch of suckers that will react to "oh no, poor cute princesses are being excluded?!" and be outraged, which makes them quite a bit of readership money.

This is not rocket science. It's yellow journalism. It's money. The news didn't care about ethics when we went into Iraq, or when we send the innocent Central Park Five black kids to jail for a rape they didn't commit. All that matters, is sensationalism to generate money.

And the people that believe it are just as guilty as the news corporations that exploit them.

Comment: Re:Tax exempt? No we don't revoke that (Score 1) 698

by Chris Katko (#49478365) Attached to: 'We the People' Petition To Revoke Scientology's Tax Exempt Status
I think it's more important to note that Obama has done literally shit all to act on any of those "We the People" petitions. Any time they hit 100k, they just write some politically-correct bullshit... or with Snowden they literally wrote nothing at all.

I mean who honestly believes Obama really cares about your/our petitions?

Comment: Re:A first: We should follow Germany's lead (Score 4, Informative) 698

by Chris Katko (#49478285) Attached to: 'We the People' Petition To Revoke Scientology's Tax Exempt Status
I think you've completely missed the important facts.

Scientology is still a religion in Germany, but they don't qualify to be state recognized religious organization because they don't do anything to benefit he community. You can be believe Jimmy Buffet is your only ticket to paradise, but he's not gonna get a tax break unless he tells you to give back to the community.

Likewise, you can call whatever you want "a company" but it's not going to be a company--and entitled to the benefits therein--unless it gets a business license.

You can call yourself a cop all you want, but unless you pass the requirements to become a LEO, you're not a cop.

That's the difference.

Meanwhile, the other major religions you listed are all giving back to the community in great numbers. So they do qualify to be a state approved religion. So this is an entirely apples to oranges, reasonable contrast between major religions and Scientology. If Scientology wants to get tax breaks all they have to do (GASP) is start giving a shit about people and trying to help them. If that burden is too high for you to become a religion, I don't think I want you anywhere near a legislative job.

I've got all the money I'll ever need if I die by 4 o'clock. -- Henny Youngman

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