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Comments

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Wave Power Fails To Live Up To Promise

skids Re:Too bad (151 comments)

There are a number of math problems here. First AC (Alternating Current not Air Conditioner :-) watts are not DC watts. They are DC
watts over (the square root of two.) So when converting from a DC value like BTU/hr you need to factor that in. Assuming a power
factor of 1, the actual equivalent DC watts of the air conditioner is about 2.5K (8500ish BTU), and will actually be less because the power factor will
be less than 1 for the type of motors used in an air conditioner.

Secondly Heat != electricity unless you are using a resistive device. You don't compare them kWH to kWH, there's a
COP involved though usually a SEER is used when talking HVAC. This COP will be well over 1, as you can move way more than 1kWH of heat with 1kWH of electricity; often several times more, but it depends on the temperatures involved. If you have a heat ballast like a ground source loop attached to a heat pump that boosts the COP dramatically.

1 minute ago
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Wave Power Fails To Live Up To Promise

skids Re:Too bad (151 comments)

The solar water heating vendors spent decades charging "what the market would bear" instead of competitively expanding/economizing. At this rate a heat pump and a solar panel may economically pass them up before they can.

44 minutes ago
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Wave Power Fails To Live Up To Promise

skids Re:Mechanical stresses ... (151 comments)

Not so much. There are location-specific seasonal variations but it is more predictable and has a more reliable baseline.

Both wave and off-shore wind suffer greatly from the transmission problem, but with off-shore wind, they get to use technology that has already been developed because it also works on land. Wave doesn't get that leg up, and still has to deal with transmission expenses.

about an hour ago
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Wave Power Fails To Live Up To Promise

skids Re:Mechanical stresses ... (151 comments)

There are some actual advatantages to the "large HAWT" design and also some amount of technological lock-in in the market. Actually that's an illustrative example to those expecting wave power to bootstrap faster than it is.

Anyway the primary advantage to large turbines are the higher the altitude of the blade at the top, the stronger and more consistent the winds are up there.

about an hour ago
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Wave Power Fails To Live Up To Promise

skids Re:Lots of problems with it (151 comments)

Wave energy is actually known as one of the less intermittent renewable resources. There is seasonal variation, but at certain sites there are pretty much always waves and it can be used as a baseline power source. The only things more reliable are tidal and geothermal.

1 hour ago
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Wave Power Fails To Live Up To Promise

skids Re:Lots of problems with it (151 comments)

Doesn't actually have to be based on the mooring. Damper mechanisms may be deployed to reduce wave shock. Dampers dissipate energy. They are essentially generators that do something useless with the resulting energy, like convert it to heat. Which is why the MIT kids evaluated regenerative shocks for cars and nobody that knew their ass from their elbow accused them of trying to make a perpetual motion machine.

1 hour ago
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Wave Power Fails To Live Up To Promise

skids Re:Golden opportunity missed... (151 comments)

It was application of modern engineering to the old idea, to attempt to make it economicaly feasible. Nobody ever claied it was "new science" because that would have been ridiculous.

2 hours ago
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Ask Slashdot: Any Place For Liberal Arts Degrees In Tech?

skids Re:Short answer (385 comments)

...Or documentation written by native and/or skilled writers of the language it is written in, capable of understanding the product at a surface level, formulating rationally structured topics, and anticipating the needs of the target audience. But the pendulum is still swinging away from that AFAICT. Instead we get random web videos that amount to a show-and-tell of "what I learned to do last week."

yesterday
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Canon Printer Hacked To Run Doom Video Game

skids Re:Nice one... (87 comments)

Prefabricated boards with attached motors, sensors, and often WiFi? Rip that out for robot guts. Screw the Raspberry Pis, arduinos, and whatnot.

2 days ago
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Canon Printer Hacked To Run Doom Video Game

skids Re: Surprising (87 comments)

Unless you have a use for the waste heat, you're better off with systems with better performance-per-watt. These are usually low wattage chips, but they can't do much math-wise.

2 days ago
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Why Google Is Pushing For a Web Free of SHA-1

skids Re:SHA-3 (108 comments)

Why? That sounds incredibly stupid. Isn't the obvious method to validate both?

You could do that too, but if the SHA3 is not deemed sufficient protection, then we are
screwed anyway. Embedded devices might choose to ignore the SHA2 to save on
compute resources.

4 days ago
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Why Google Is Pushing For a Web Free of SHA-1

skids Re:SHA-3 (108 comments)

Well, if x509 has simply allowed for multiple signatures, we could just put both SHA2 and SHA3 signatures on the certs, and consumers of the certs could move towards supporting SHA3 as their security requirements dictate, ignoring the SHA2 signatures when they have a SHA3 signature available to them.

But as with everything PKI related, the people making the calls have some blind spots when it comes to making things forward compatible or even particularly maintainable. It's as if they've never had to a day of PKI gruntwork in their life.

about a week ago
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Ask Slashdot: What Are the Strangest Features of Various Programming Languages?

skids Re:C has bigger problems than that trivia (729 comments)

Null terminated strings are a bigger problem. What do you do if you want to embed nulls in a string? Not use the entire string.h library for starters, have to write your own routines.

Yes. Because those are different constructs. Live with the fact that both are useful.

Having the length makes a strlen function trivial and run in constant time

And having a hash makes ==/=! run in constant time most of the time. And then you could also add an indicator for encoding. And some flags for the garbage collector or if not that at least a COW flag. And then suddenly you find you're using more than a cache line for just one variable in a critical code section even when you're pabsolutely sure the string can only contain "TRUE" or "FALSE". And that is part of why my applications seem to run slower and slower every year despite my hardware being upgraded.

Personally I prefer functions to use parens. Like in math. It makes sense visually and keeps things organized. Are you allergic to the shift key or something, or do you just enjoy the mental challenge of parsing things in your head. You'd seriously prefer this:

thingA thingB thingC,4,7,thingD thingE

to this:

thingA(thingB(thingC(4,7)),thingD(thingE))

?

For which one do you have to consult the documentation, if even extant, to figure out the arity of things?

about two weeks ago
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Ask Slashdot: What Are the Strangest Features of Various Programming Languages?

skids Re:Null Terminated Strings (729 comments)

I'd still prefer if pointers could keep both address and size of the buffer.

Then use a struct with pointer and length. Use the right tool for the right job. ZTSs are for things that utilize the efficiency of knowing nothing is sending you strings longer than you can handle efficiently and can take advantage of not having to worry about syncing a length counter in RAM. If you use the functions that use ZTSs for multimegabyte content that you need to find the length of frequently, you're using them wrong.

As crotchety as C is, at least they realized that a toolbox full of nothing but powered hammerdrivers is less than fully useful.

(If only they had handled endianness better. Or at all.)

about two weeks ago
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Mozilla 1024-Bit Cert Deprecation Leaves 107,000 Sites Untrusted

skids Re:FTFA (67 comments)

People can complain as much as they want

Yep, that about sums up the Internet.

Only half. The other half is "and still get screwed over."

The cert authorities as a whole, following NIST recommendations, decided to not just stop issuing 1024 certs, but also to revoke their 1024 root certs, so anything checking CRLs would just break. Months before the actual deadline. They could have just let those certs run out on schedule, but that wasn't good enough for NIST. Moreso, they could have only sold them such that they ran out on schedule (we were sold a 5-year 1024bit cert in 2009 when the deadline had been set at EOY 2011 since 2005). After an extension by NIST from EOY2011 to EOY2013, made in 2011, the number of certs issued with expiry times much past the deadline was likely pretty small (so in case the NIST estimate of when someone would have the compute power to crack our cert was off by 6 months, we had to swap it out a year early distracting us in the middle of more important things.) Anyone concerned enough to worry that an obscene amount of CPU power would be dedicated to compromising their particular cert would have changed them voluntarily, and even the laggards would have likely made it under the wire before any serious attack on their crypto infrastructure. Finally, lots of people use these certs in internal settings where the crypto isn't the sole security and the real value of the cert isn't crypto but the fact that users don't have to install a site-owned PKI CA root certificate to get the "annoying popups" to stop.

Sooo... it was fortunate that almost nothing was checking CRLs during all that, though as a general state of affairs that also needs to be fixed.

Oh sure, the CAs offered free bridge certs to "make up" for the whole thing. Not good enough. They should have comped an extra year on for free or something. Since they didn't there should have been class action suit to make them pay for the hassle.

People need to quit breaking shit on a whim.

about two weeks ago
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You Got Your Windows In My Linux

skids Re:Troll much? (613 comments)

This is BS. "Learning" SYSV configuration takes 15 minutes to explain run levels

...and an understanding of shell scripting including obscure parts you normally don't use on the CLI ...and familiarity with many commandline utilities. ...and understanding how your package manager handles upgrades that touch the init scripts ...and eventually figuring out why half of the setup of facility FOO is in 51-pre-FOO and the other half is in 99-post-FOO ...and then figuring out that you could get away to moving that to 50-pre-foo so it gets run before 51-pre-bar, 49-pre-FOO won't work ...and the options to your system's start-stop-daemon or equivalent ...and how to get all the stuff called from the init script to belch debug info on demand, if that's even supported.

While personally I think all of the above is still preferable to memorizing what exactly things like RestartPreventExitStatus and ReloadPropagatedFrom mean, and being able to remember their names when you need to use them, it's a difference of margins not a giant difference.

about two weeks ago
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You Got Your Windows In My Linux

skids Re:Troll much? (613 comments)

Well, actually I wouldn't say I'm an advocate more than I just recognize that's it's got enough good points and enough traction that it'll be part of my life in the future whether I end up liking it or not.

about two weeks ago
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You Got Your Windows In My Linux

skids Re:Troll much? (613 comments)

You do have to put a fraction of the time you did in 30+ years of learning your way around SYSV systems into actually learning systemd in order to expect the same level of proficiency. Someone who hadn't your experience would find SYSV just as confusing; if you don't think so you are underestimating your level of learnedness..

That said, yes, the biggest problem with systemd is the large volume of non-mneumonic, inconsistent identifiers that were obviously chosen in a caffeine-induced fit of megalomania, and the fragmentation of the source between internal code and config files. However, even more traditional systems have started to similarly fragment things, what with things like udev rules smattered around in share/lib directories and not just under /etc anymore and distro scripting frameworks likewise.

Those who think systemd is "dumbed down" after listening to an advocates "it's easy" sales pitch, or because it tries to squash everything into the (yes, incorrigibly stupid) flat sectional config file fomat could not be more mistaken, however. It is actually just trying to improve total system modularity and break some longstanding unnecessary interactions. Some of that it is doing in sophisticated ways, and some of that it is screweing up in some pretty stupid ways. It's now been turned loose on the world and will have to be tamed; it is not just going away because there will be plenty of people who learn to use it effecitively.

about two weeks ago
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You Got Your Windows In My Linux

skids Re:Troll much? (613 comments)

It only runs on Linux, and will only ever run on Linux

Good. It can use the benefits of Linux without having to cripple itself to conform to portability abstractions.

Way to much blood sweat and tears have been spilled at the portability altar.

about two weeks ago

Submissions

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MA "Right To Repair" initiative still on Tuesday ballot, may override compromise

skids skids writes  |  about 2 years ago

skids (119237) writes "MA voters face a complex technical and economic question Tuesday about just how open automobile makers should be with their repair and diagnostic interfaces. A legislative compromise struck in July may not be strong enough for consumer's tastes. Proponents of the measure had joined opponents in asking voters to skip the question once the legislature, seeking to avoid legislation by ballot, struck the deal. Weeks before the election they have reversed course and are again urging voters to pass the measure. Now voters have to decide whether the differences between the ballot language and the new law are too hard on manufacturers, or essential consumer protections. At stake is a mandated standard for diagnostic channels in a significant market."
Link to Original Source
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House Panel Approves Bill Forcing ISPs Log Users

skids skids writes  |  more than 3 years ago

skids (119237) writes "Under the guise of fighting child pornography, the House Judiciary Committee approved legislation on Thursday that would require Internet service providers (ISPs) to collect and retain records about Internet users’ activity. The 19 to 10 vote represents a victory for conservative Republicans, who made data retention their first major technology initiative after last fall's elections. A last-minute rewrite of the bill expands the information that commercial Internet providers are required to store to include customers' names, addresses, phone numbers, credit card numbers, bank account numbers, and temporarily-assigned IP addresses. Per dissenting Rep. John Conyers (D-MI): 'The bill is mislabeled ... This is not protecting children from Internet pornography. It's creating a database for everybody in this country for a lot of other purposes.'"
Link to Original Source
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CIA drones may have used illegal, inaccurate code

skids skids writes  |  more than 3 years ago

skids (119237) writes "Coders hate having to rush code out the door before it's ready. They also hate it when the customer starts making unreasonable demands. What they hate even more is when the customer reverse engineers the product and starts selling their own inferior product. But what really ticks them off is when that buggy knockoff product might be used to target military unmanned drone attacks, and the bugs introduce errors up to 13 meters. That's what purportedly happened to software developer IISi based on an ongoing boardroom/courtroom drama that will leave any hard-pressed coder appreciating just how much worse their job could get. The saddest part? The CIA assumed the bug was a feature. The tinfoil-hat-inducing part? The alleged perpetrators just got bought by IBM."
Link to Original Source
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Hacking Big Brother with help from Revlon

skids skids writes  |  more than 4 years ago

skids (119237) writes "All those futuristic full-face eyeliner jobs in distopian cyberpunk fiction might not be that far off the mark. A New York University student spent his thesis time exploring computer vision technology (OpenCV) for ways in which one could confound first-stage algorithms that initially lock onto faces. Then he mixed in a bit of fashion sense to predict future geek chic. Now, whether you want to go for the coal-miner look just to stay out of the data mine, that's up to you..."
Link to Original Source
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Digital Photocopiers Loaded With Secrets

skids skids writes  |  more than 4 years ago

skids (119237) writes "File this under "no, really?" CBS news catches up with the fact that photocopiers, whether networked or not, tend to have a much longer memory these days. When they eventually get tossed, very few companies bother to scrub them. Coupled with the tendency of older employees to consider hard-copy to be "secure", and your most protected secrets may be shipped directly to information resellers — no hacking required. "The day we visited the New Jersey warehouse, two shipping containers packed with used copiers were headed overseas — loaded with secrets on their way to unknown buyers in Argentina and Singapore.""
Link to Original Source

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