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Computer Chess Created In 487 Bytes, Breaks 32-Year-Old Record

tibit Re:Best short programs (199 comments)

Probably if they allowed themselves to use the full 512 bytes, it could enforce all the rules. Alas, I wonder what would come out with APL :)

2 days ago
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Proposed Space Telescope Uses Huge Opaque Disk To Surpass Hubble

tibit Re:keeping station behind it? (124 comments)

As crazy as it might sound, the GP-B mission has validated means of following a zero acceleration orbit with sub-micron precision. The precision achieved was that the residual acceleration was on the order of 1E-11 g. So yeah, we can definitely follow a zero-acceleration orbit with crazy precision!

3 days ago
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Ask Slashdot: Is Pascal Underrated?

tibit But Pascal *is* in widespread use!! (488 comments)

Everyone here seems to forget that a variant of Pascal is, for better or worse, also standardized as an IEC 61131-3 language. It's called Structured Text (ST). It is in rather widespread use in industrial automation. ST is also one of the languages you can use to write the actions of the Sequential Function Charts (SFCs), also known as Grafcet. SFCs provide most of UML State Diagram functionality. Standardized support for state machines is still not in C++, after so many years!

So Pascal isn't dead in the mainstream, it's just that it's not the mainstream you might think of. A lot of products in your fridge have been packed in machines controlled in part by Pascal code.

3 days ago
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Ask Slashdot: Is Pascal Underrated?

tibit Re:Modula-3 FTW! (488 comments)

I wrote a lot of I/O code/drivers in Pascal, and also what would pass for a rudimentary run-to-completion realtime OS kernel. There was nothing fundamentally worse about it, compared to C, except for the lack of finesse in the code generator. It worked just fine, and I'd rewrite in assembly the few functions/procedures that had to be faster than compiled code.

3 days ago
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Government Recommends Cars With Smarter Brakes

tibit Re:I have an even better idea (304 comments)

i've driven more hours than most olympians have trained

If you are not a professional full-time driver then no, you have not. And if you are a professional driver, then still you have not been scored on your driving.

3 days ago
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Government Recommends Cars With Smarter Brakes

tibit Re:I have an even better idea (304 comments)

This government regulation isn't about protecting you from idiot drivers. It's about protecting you from the long tail of accidents that happen in spite of everyone following the rules. People aren't infallible. Occasionally, we make mistakes even with the best of training. Unless you're a race driver, your driver "training" is nowhere near the amount of training the olympic athletes receive. Yet, invariably enough, in every olympics there's a bunch of snafus committed by the best trained people. That should be the only thing you need to see to realize that, once again, no matter how well prepared you are, you will make mistakes even if your weally, weally wish not to. I mean fuck, these people are fucking competing for olympic medals. They are the best of the best worldwide. And they do mess up. So yes, no matter how good you think you are, you will commit random errors on the road that may prove deadly. The regulations and the technical means here are to make those random things less deadly. That's all.

about a week ago
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Insurance Company Dongles Don't Offer Much Assurance Against Hacking

tibit Re:Time for the Ransomware (199 comments)

I think that the part of the issue is that there's really not all that much standardization that has force of law when it comes to ECUs. It's sad to see that they use an ECM that has such silly issues.

about two weeks ago
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Shanghai Company 3D Prints 6-Story Apartment Building and Villa

tibit For a sufficiently low value of "printed" (98 comments)

The printed part is a concrete skeleton that acts as a form that needs to cure and then be filled with concrete. None of the finishing work is printed. It is basically a cast-concrete structure, where the typical metal forms were replaced with a 3D-printed skeleton. Of course the printed skeleton is a couple orders of magnitude rougher than what you'd get with metal forms, so the walls need heavy finishing before they can be presentable.

What they've done is perhaps a step in the right direction, but they are very, very far from truly 3D-printing an entire building. First of all, they'll need to have an inline concrete mixer that can continuously mix a fast-curing mix, so that they could print shapes that are filled-in. They also need to change the shape of the nozzle so that the deformed (compressed) shape will be rectangular, and not oval as it is now. They really did everything without much thought or understanding of what it takes to do it right. It is, at best, cargo cult 3D printing. They did all the right moves without understanding what it really takes to do it.

about two weeks ago
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Innocent Adults Are Easy To Convince They Committed a Serious Crime

tibit Re:The (in)justice system (291 comments)

needed to take all cases to trial

Nope. They simply don't take all cases to trial, and some crimes go unpunished. As happens now anyway, since with a plea bargain you're punishing some other crime, not the one that really happened. You really need to look outside of the U.S. legal system. In many a European country, a crime won't be prosecuted for the reason that it had low social consequences. It's IMHO a rather valid reason not to prosecute, it's in fact what the U.S. prosecutors have yet to learn. Yeah, the law says that you shouldn't smoke marijuana. Yeah, you did break the law. No, it didn't really cause much suffering for anyone. Thus, no prosecution. That's how it's supposed to be in the civilized world. Of course, ideally we shouldn't have stupid laws to begin with.

about two weeks ago
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Innocent Adults Are Easy To Convince They Committed a Serious Crime

tibit Re:The (in)justice system (291 comments)

You're just making a bunch of stuff up. Plea bargains and prosecutorial discretion are entirely separate issues. What, you think that in jurisdictions without the plea bargain, the prosecutors take all cases? You're nuts.

about two weeks ago
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Insurance Company Dongles Don't Offer Much Assurance Against Hacking

tibit Re:Direct connect (199 comments)

The problem is that you have a system that's not inherently safe - it merely rides on the unproven safety of one single component. A resilient system would have many barriers that you have to break down in order to gain access. This one has just one. For all we know, it has already been broken.

about two weeks ago
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Insurance Company Dongles Don't Offer Much Assurance Against Hacking

tibit Re:Time for the Ransomware (199 comments)

how stable EEPROM is compared to PROM

Electrically-programmable fused PROMs suffer from bit rot and simply are not made anymore. I hate the damn things with a passion, they are one of the causes of good legacy test equipment turning getting bricked. The legacy OTP EPROMs require high voltage for programming and the only concern with them is slow charge decay. These days, it's FLASH all the way.

Alas, you're making up imaginary problems. Every high-rel firmware-based system will not only verify the integrity of the firmware upon boot-up, but continuously during operation. I mean, heck, we're not even talking about the cars here - my washer and dryer are both running continuous firmware CRCs in the background, all the time, as well as RAM integrity and plausibility checks.

Never mind that the inside of an ECU module is quite isolated from exterior noise. Every circuit going through the box has extensive filtering and surge protection. The logic supply voltages will be within spec all the while the battery voltage swings every which way (think of a range from single volts to a hundred or two).

about two weeks ago
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Insurance Company Dongles Don't Offer Much Assurance Against Hacking

tibit Re:Is it really a surprise? (199 comments)

It's not hard, it's simply not part of the usual product specs. The device is supposed to do stuff, that's the primary thrust when doing the development. The mindset of the entire industry must change before we start expecting things to be secure but otherwise buggy first, not - as it is now - functionally perfect but insecure.

about two weeks ago
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The Legacy of CPU Features Since 1980s

tibit Re:1980s? (180 comments)

Moreover: which cycles? Core? FSB? Memory? Eh? Under what test conditions?

about two weeks ago
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The Legacy of CPU Features Since 1980s

tibit Re:1980s? (180 comments)

Given that we had 80-bit extended precision FPU registers in 8087 chips 30 years ago, I don't think the 64-bit path/register assertion holds any water. I have lots of code that uses 128 bit registers and runs on pretty boring consumer CPUs. The reason to increase data path width is not to address more data, but to increase the throughput. I use 128 bit registers with code that uses no virtual memory and runs with a couple MBytes of RAM.

about two weeks ago
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The Legacy of CPU Features Since 1980s

tibit Re:Yeah, I remember when VMWare first came out... (180 comments)

I was running VMs on Z80 hardware - it was slow, since they were software-emulating the CPU (I did 6502 and Z80), but hey, you don't need any special hardware or CPU features for virtualization. The special features are performance optimizations, nothing else.

about two weeks ago
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The Legacy of CPU Features Since 1980s

tibit Re:Yeah, I remember when VMWare first came out... (180 comments)

Not only do their prices sting, but they suffer heavily from living on their own little island and steadfastly refuse to use standard terminology, and seem to be doing a lot of stuff differently just because they can - not because it makes sense.

about two weeks ago
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Microsoft Ends Mainstream Support For Windows 7

tibit Re:Nostalgic for Windows 7? (640 comments)

For whatever reason, VirtualPC/XP was always sluggish compared to VMware with an XP VM on the same machine, with same host OS and otherwise identical settings. And this wasn't on underpowered hardware either.

about two weeks ago
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Microsoft Ends Mainstream Support For Windows 7

tibit Re:Nostalgic for Windows 7? (640 comments)

I'd perhaps add that OS X didn't have any revolutionary changes in its UI, like we got with Windows 8. The dock is still here, 10 major OS X releases after the first one. The stoplights in the title bar are still there, too. Things have changed around multi-screen, virtual desktop and full screen modes, certainly, and we've got Spotlight halfway along the way (10.4). I've been using OS X as my main desktop since 10.5, and it seemed to be mostly painless experience, with very little re-learning needed to go between versions.

about two weeks ago
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Chevrolet Unveils 200-Mile Bolt EV At Detroit Auto Show

tibit Re: Only 30 Grand? (426 comments)

$200 is roughly a monthly lease on a Volt.

about three weeks ago

Submissions

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MRI Magnets Cause Nystagmus

tibit tibit writes  |  more than 3 years ago

tibit writes "In an interesting twist on "it's so old it's new again", Johns Hopkins researchers led by Dale Roberts found what must have been causing much confusion for doctors the world over: strong external magnetic field can stimulate the semicircular canals, causing vertigo and nystagmus (pendular eye motion). It's a textbook case of Lorentz force in action: our angular rate gyros, the semicircular canals in the middle ear, filled with endolymph, have a ionic current flowing across. In magnetic field, the current produces a force that pushes the lymph along the channel, causing stimulation of the cupula — a pressure sensor at the end of the channel. This is interpreted by the brain as rotation of head in space, and causes a nystagmus that's supposed to stabilize the image on the retina. Of course the subject is laying down and not spinning in space, and the mismatch between inertial measurements coming from the ear and real situation causes vertigo."
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