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Comment: Re: Time for Wine (Score 1) 156

by pz (#48869781) Attached to: Windows Server 2003 Reaches End of Life In July

Really? Fired? Funny, 'cause I'm the boss. If we had an application running under Windows 95, _and it worked_, there would be absolutely zero reason to do anything with that machine when there are other, more important, ways to spend our time. Granted, that hypothetical machine would not be on the net, 'cause we aren't stupid.

The real machines we have running XP, run our experiments (and they have never been on the net for other reasons); until such time as the boxes die, they will continue to run our software, and continue to run it under XP. And then, they will be replaced with the identical backup hardware we have, giving us enough time to get a grant funded to have someone port the code to a more modern system. Until then, we have science to do. Computers, in my lab, are like any other tool that is to be used to collect data and advance knowledge -- pens, screwdrivers, oscilloscopes, whiteboards -- and are not an end unto themselves.

Comment: Re:Time for Wine (Score 2) 156

by pz (#48864327) Attached to: Windows Server 2003 Reaches End of Life In July

Didn't work for us. We have an application that has been developed over about 10 years in VB6. No one has the budget -- either in finance or time -- to port. We looked at Wine as a plug-and-play replacement for XP and the application did not work correctly, 100%. The application is mission-critical, making anything less than 100% compatibility a non-starter. So we're stuck with XP until the next big grant comes in and we can afford to pay someone to port it to a more modern system.

Don't get me wrong, Wine is an impressive amount of work, and my hat is off to the brave folks who have put so much time and effort into it. It just isn't good enough for our needs, unfortunately.

Comment: Re:So what do we expect to see? (Score 1) 219

by pz (#48784087) Attached to: LAPD Orders Body Cams That Will Start Recording When Police Use Tasers

A large reduction in taser use, higher reports of police brutality, slightly higher use of lethal force?

My crystal ball says that there will be an unexpectedly high level of malfunctioning video equipment, triggering a big-money follow-on contract with the manufacturer to correct the problem. The follow-on contract will achieve a just-above the threshold of measurability improvement in reliability. Then, later, when the current brouhaha has been forgotten, the cameras will be left to accumulate drawers with the official evaluation that they were fundamentally defective and so no longer required. And, of course, the real problem will be intentional damage to the equipment caused by the officers required to wear them who have something to hide.

But perhaps I've got my cynical hat on ...

Comment: Karadashev Type II Civilization (Score 2) 300

by pz (#48754049) Attached to: The Search For Starivores, Intelligent Life That Could Eat the Sun

Aren't these folks just looking for a Karadashev Type II civilization? That was defined, oh, about 50 years ago, now. By an astronomer.

Talk about not bothering to look at what people in a given field have done before impinging upon your own self-important program. If anyone bothers to read the linked article (I do not recommend wasting your time), it's full of blatheringly idiotic statements about how major advances in science come about. I'm a scientist, in a different field, and we are pushing the boundaries as hard as you can imagine. We look at anything and everything that we can find that is relevant to help us succeed at our, frankly, audacious, high-risk work. And there are one or two people in the field who are blathering idiots like this who keep on talking about pie-in-the-sky visions they have for how things should work ... and they contribute nothing. Meeting after meeting, they provide the same drivel without doing any work, rehashing old ideas. Sure, they have entertainment value, but given the level of commitment and intensity to success that others have in the field, they are an unnecessary distraction and serve only to dilute the efforts, not build upon them.

Comment: Re:No big changes (Score 4, Interesting) 578

by pz (#48724583) Attached to: What Language Will the World Speak In 2115?

Yes. French was the international language 100 years ago. English was (at that point) an also-ran.

Interesting observation: in modern-day Poland, when you ride the train, there are multi-lingual signs instructing on how do do things like open the windows or operate the toilet. The signs appear in Polish (it's Poland, after all), German (much of Poland was Germany and vice versa), Russian (it was under the Soviet sphere of influence), and French (the international language). No English.

Comment: Re:What does it change? (Score 2) 290

by pz (#48704525) Attached to: War Tech the US, Russia, China and India All Want: Hypersonic Weapons

It's funny that comments from low user ID folks always seem more insightful and measured these days. And it's swb's low ID that makes me respond at all to the posting.

North Korea seems defined by the notions of a rational actor and bound by the notion of self-preservation, whereas Islamic groups seem to better fit the idea of a non-rational actor for whom self-preservation isn't a criteria.

Yes, but, there is certainly a large dose of not-quite-rationality that NK exhibits when dealing with international actors. They don't have the same rule book as everyone else seems to when it comes to how to treat your large, powerful neighbors. It reminds me of how people sometimes become when they spend too much time alone, separated from society: they behave in ways that are explicable, and therefore rational, but distinctly out of pace with expectations, and get labelled, "a bit crazy," or, "kind of odd." NK is like a weird old uncle who lives by himself and keeps rats as pets. Rationality applies, self-preservation applies, but there is most definitely something not right, as if they are delusional about the way the world works.

Comment: Re:This is why "biometric" authentication is usele (Score 3, Insightful) 80

by pz (#48686779) Attached to: Chaos Computer Club Claims It Can Reproduce Fingerprints From People's Photos

I always think of security like the Miller-Rabin test for primality (which is really a test for a number being composite): it does not give an absolute assurance, but each time you test a given candidate again with a new challenge, you reduce the probability that the candidate is composite, and each test is orthogonal to the previous ones. You, the designer of the system requiring confidence that a big number is prime, get to select your confidence level by adjusting the number of tests applied.

So too, then, you, the designer of a security system requiring confidence that a given person is who they claim to be, get to select your confidence level by adjusting the number of factors required. A brass key gives a certain level of confidence. An iris/thumbprint/palmprint/voiceprint scan another. An RFID card another. A PIN/password another. Being recognized by a guard another. Each is orthogonal to the rest.

Comment: Better solutions exist (Score 1) 232

by pz (#48628831) Attached to: Ask Slashdot: What Can I Really Do With a Smart Watch?

How about the extra-ordinary solution of wearing your phone in a pocket that IS accessible within the clean room? Or in one of those exercise arm-band thingies to hold it on your arm outside the gown? There are also bracelets that you can wear that warn you if you get too far from your phone which are inexpensive, so you won't forget your phone in the clean room

The real question becomes what is allowable for you to wear in your clean room. I'm a little surprised that a watch would be OK, or that bringing your phone in would be OK, but I suppose it depends on the situation.

Comment: Re:The Batman, Theater Attack Comparison (Score 1) 580

by pz (#48628687) Attached to: Reaction To the Sony Hack Is 'Beyond the Realm of Stupid'

Everything in this decision has to do with LIABILITY. Even if the probability is extremely low, the potential liability is astronomical. It doesn't make financial sense for Sony to allow the movie to be shown.

If the expected value of an attack being carried out at all is reasonably high, in other words, there is a credible threat, then that probability is piled all onto the theater that premiers the film. The probability in a credible threat might approach, say 10% (I'm guessing). As an individual, I would not play 1-in-10 odds when the potential outcome is my death. If instead Sony were to open the film in, say, 10,000 theatres simultaneously, the potential liability for each theatre operator drops substantially for any location, and at 1-in-100,000 becomes low enough to perhaps ignore by an individual going to the movies. However, the overall liability remains at 1-in-10 for Sony. The movie is not going to be shown.

Comment: Re:overwhat? (Score 1) 191

by pz (#48606287) Attached to: Jaguar and Land Rover Just Created Transparent Pillars For Cars

Agreed. My initial reaction to the CGI video is, "wait, why did they TURN IT OFF?!! That's useful information!!"

I can do without the heads-up stuff they were doing (do we really need to be warned about pedestrians like that, or how many parking spaces are available at a garage that we're passing?), but the A and B pillar pseudo-/virtual-transparency are awesome.

Comment: Re:Not really missing vinyl (Score 1) 433

by pz (#48600389) Attached to: Vinyl Record Pressing Plants Struggle To Keep Up With Demand

Perfectly isn't hyperbole here. That is mathematically shown.

And the part of perfect reconstruction that nearly everyone forgets is that it requires an infinitely long sampling of an infinite-time signal. If you use a time-limited sequence, you do not get perfect reconstruction. I've been in the business of signal sampling and reconstruction a long time, but I'm still having trouble finding an instance of a sampling that spans infinite time (for those who are humor impaired, that was a joke).

More practically speaking, because all digitizations that you come across, or design, have finite time span, it means that the reconstruction accuracy starts to get worse and worse the closer you get to the Nyquist threshold, and the effect is worse and worse the shorter the sequence length. Here's an extreme thought experiment: you have two samplings of a signal just a hair below Nyquist. Just a hair below. The sequences are both pretty short, say 4 samples long.

In the first sampling, you got unlucky, and the samples all happened very close to the zero crossings so that all of the quantized values are 0. Reconstructing that yields a DC value of 0V.

In the second sampling, you got lucky to the opposite extreme, and the samples all happened very close to the peaks, so that the quantized values are alternately +PEAKVALUE and -PEAKVALUE. Reconstructing that yields the original sinusoid at the intended amplitude.

Which sampling is correct? If I just give you the sampled values, there is no way to tell. Any reconstruction from amplitude 0 to amplitude PEAKVALUE would be accurate, and there is no way of knowing for sure what the phase was.

Now, if the sequences were infinite length, then, eventually, no matter how fine that hair was below Nyquist, you'd start to see the beating against the sampling clock, and, eventually, be able to observe samples that spanned the entire range of the sinusoid, making accurate reconstruction possible, including phase. But, again, you'd need an infinite sequence, with an infinite sinusoidal signal.

What are the real-world consequences of this problem? (1) you lose phase and amplitude information of the original -- they CANNOT be reconstructed accurately -- as you approach Nyquist, with the effects getting more and more pronounced as the sequence length gets shorter and shorter. (2) If you really want dead-on accurate reconstruction up to a frequency F, you should be sampling at 5F, not 2F. That also gives you more room to design good anti-aliasing filters on the sampling side, and carrier frequency filters on the reconstruction side.

Remember, people, Nyquist is the mathematical limit, not the practical, usable threshold.

Comment: Re:its not as if american cops have anything to fe (Score 4, Insightful) 515

by pz (#48582755) Attached to: Once Again, Baltimore Police Arrest a Person For Recording Them

I would suggest that when someone is being choked and can barely breathe, their words will not be complex, nor will they carry nuanced meanings such as the level of difficulty they are having with respiration. When faced with life-threatening situations, our minds focus, and become exceedingly direct: "I can't breathe" is entirely within the acceptable range of philosophical inaccuracy under those circumstances. You wanted him to say, instead, "my fellow man, I'm having a rather hard time re-oxegenating my blood -- would you mind releasing the pressure on my trachea for a moment?" Or, "I'm panting because you're crushing my thorax, and am unable to draw a full breath -- would you mind removing your knee from my chest?" Or, "my inability to form full words is because you've pinched off my carotids, and I'm facing imminent loss of consciousness -- would you mind removing your bear-sized hands from my neck?"

If someone in a highly stressful situation tells you "I can't breathe" then you should act accordingly to prevent loss of life. Simple as that.

Comment: Different Comparison Needed (Score 1) 377

by pz (#48571347) Attached to: Bellard Creates New Image Format To Replace JPEG

Although the comparison pages posted in this thread (this is an awesome one https://xooyoozoo.github.io/yo... ) are fun and interesting, they compare the bit efficiency of the two algorithms. That is important yes. But that isn't how these formats are used: when bandwidth is an issue (and it is to web site authors, be they individuals or companies, no matter what anyone on this thread says to the contrary), compression is increased to the threshold of perceptibility, or a little beyond. That is, the provider will increase compression until artifacts are just barely noticeable.

So, the more pertinent question, in terms of image quality, is how the two algorithms compare for equal levels of error, both in number of bits, and also in subjective image quality.

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