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Comment Re:Two dirty words harry reid (Score 4, Informative) 340

Old vaults of waste have been found to be developing cracks and been reinforced.

It's faaaaar worse than that. One of our borehole geophones came back from a job at Hanford with the 1/2" thick aluminium tube so eaten away that it had to be replaced. That would be 100's of meters down a hole (I think they had a 500m cable...).

Mars

NASA: Curiosity Has Found Plastic On Mars 293

dsinc writes "Last week Curiosity was able to use its SAM (Sample Analysis at Mars) device to confirm the discovery. A robotic arm with a complex system of Spectral Analysis devices was able to vaporize and identify gasses from the sample, concluding that it is in fact plastic. How plastic formed or ended up on the Martian surface is quite an exciting mystery that sparks many questions. The type of plastic sampled as we know so far can only be formed using petrochemicals, meaning not only that there could possibly be a source of oil on the Red Planet, but that somehow it got turned into plastic. Even more interesting is that oil or petrochemicals used to create this type of plastic are only known to come from ancient fossilized organic materials, such as zooplankton and algae, which geochemical processes convert into oil pointing to the earthshaking evidence that there was once life on mars. 'Right now we have multiple working hypotheses, and each hypothesis makes certain predictions about things like what the spherules are made of and how they are distributed,' said Curiosity's principal investigator, Steve Squyres, of Cornell University. 'Our job as we explore Matijevic Hill in the months ahead will be to make the observations that will let us test all the hypotheses carefully, and find the one that best fits the observations.'" Update: Yes, it's a hoax

Comment Badly written, but essentially correct (Score 1) 296

Read through the entire thing, but am very unimpressed with the quality of the writing. If re-written at a higher skill level and otherwise massaged, I think it would make an ideal document (stamped by the GOP of all groups) to send around to our local congresscritters as a talking point. Wonder if the sponsor could be convinced to let it be "fixed" without changing the content or message, and updated?

Comment Re:Headers (Score 5, Insightful) 562

Yeah but if someone gives you a bag containing 1000 pounds of (minced) beef, then you empty the beef out and some of the beef is stuck to the insides of the bag, and you throw the bag away you can't claim that you didn't originally receive 1000 pounds of beef.

I think you've got that wrong. If they're measuring DSL overhead, error correction, etc then the proper analogy would be:

Somebody sells you a crate of apples they claim is 1000 pounds. What they neglected to tell you was that the crate itself weight 200 pounds, and they included that in their calculation. You only got 800lbs of actual apples.

Comment Re:All on consumer grade drives..... (Score 1) 273

Any even marginally architected system can deal with disk failures, and indeed *must*. The difference between using masses of consumer disks and a few enterprise disks is that while a failed consumer disk in a massive pool might cause a slight slowdown spread across all of your users, a failed enterprise disk in a business-critical system can ruin your whole day even if you *don't* lose any data. Remember how Google just lets hardware die and replaces it on repeated passes through the datacenter? Same thing.

Comment Re:Psychoacoustics and perceptual coding (Score 2) 361

sorry, but you are wrong.

for people like me (50's) I can't hear the details. beyond a point, it sounds 'good enough' for me. we each have our own threshold of where 'good enough' is enough.

BUT, don't assume that a mastering engineer is going to have as dull a set of senses as you or I typically do. master chefs can taste their cooking creations to fine levels. pro photographers can obsess about micro-contrast and details. a lot of fields have sensitive observers.

I've known people who can detect absolute polarity (phase wiring on the back of your spkrs). I can't, but I've seen someone be able to tell, almost right off. people are not faking it! some have very good hearing. most don't, but don't judge by JUST your own experience.

Um, I'm not going by "my experience" at all, this is fundamental and *very* well-understood physiology, not to mention basic physics. *All* human ears exhibit the masking effect, because (as expanded on by someone else below) there is a fixed dynamic range possible in the construction of the ear. Actual muscles and bones *move* to "change the input gain" in the ear, just like your pupils change size when it's bright or dark out. Some people have a wider intrinsic dynamic range than others, but only by a narrow margin. If you can show me somebody who's pupils never change size yet they can see perfectly well in both extreme dark and full sunlight, then we can talk.

As for detecting speaker polarity, I can absolutely guarantee you that they are detecting *mixed* polarity: wire the left speaker one way and the right speaker "backwards" and they can sense it (I bet I could too). Wire *both* speakers "backwards" and there is no possibility anybody is going to be able to detect it. Anybody who insists otherwise is also going to refuse a double-blind confirmation.

Comment Re:Psychoacoustics and perceptual coding (Score 1) 361

The only difference between the pure sine and the piano is harmonics. If you couldn't hear harmonics you couldn't tell the difference between a guitar or a piano -- the only difference is the harmonics.

I was generalizing for the consumption of people who no relevant background, and should have been more specific. Harmonics are absolutely important, but not all of them. The challenge in perceptual coding is figuring out which harmonics are functionally relevant.

Also you are correct that Nyquist sampling is *not* sufficient for human perception of higher frequencies, as it introduces quantization and phasing errors if there aren't enough (or an integer number of) "samples per wave". It bugs me when people who ought to know better (Opus!!!) keep claiming this.

Comment Psychoacoustics and perceptual coding (Score 4, Informative) 361

He clearly doesn't understand the first thing about the human ear or brain. The *bitrate* is 5% of the original CD, but the human-effective *datarate* is ~95%. That last ~5% of the signal is various harmonics, twitchy bits, and other stuff that the human ear is simply incapable of hearing, but in terms of actual spectral data it's pretty incompressible. Lossy audio compression makes the perfectly legitimate trade-off that you can completely skip that incompressible chunk of the audio signal that the human ear can't actually hear, and save bandwidth.

Modern psychoacoustic models take into account both the physical and mental limitations of the human body. A prime example is "masking", where a louder sound will completely overcome a quieter sound, and do so for a period *longer* than the loud sound. Think of the ear as having an AGC with a slow response: it has to adjust the "gain" for the louder sound and ends up missing the quiet bits before it, then has to adjust the gain back down before it can pick up the quiet bits after. Simple compression trick: toss the quiet bits cause you can't hear them anyway.

What's clear is that he's just fronting for the latest in a long line of "we're better at this than the entire rest of the world combined" snake-oil audio companies with a nifty little lock-in strategy. Just read the list of trademarks.....

Comment Re:Just whiners (Score 1) 607

Showing at this festival were dozens of HD+ short films, not a DVcam in sight. The capstone of the festival was one of the (if not *the*) first showing of Toy Story in HD on a big screen. I could see pixels because it was only 1080p (and I got a late seat up close), but otherwise it was a *radically* new and infinitely superior experience. These days I *actively* avoid non-digital theatres because the physical intra-frame jitter on a film project is almost a guaranteed migraine.

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