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Comment: GPS vs inertial navigation (Score 1) 298

by przemekklosowski (#47071809) Attached to: Is It Really GPS If It Doesn't Use Satellites?
Well. we had inertial navigation using gyroscopes for a long time now. At first it was mechanical gyroscopes, subsequently replaced with fiber loop optical gyros. Those gyros are quite a feat of precision---I think the best ones have the drift small enough so that you could navigate for extended periods. So why did we replace them with GPS? Well, they are much more expensive, larger and fragile compared to purely electronic GPS receivers.

BTW, I recently learned that the GPS system began as a clever hack by JHU APL engineers, who determined the orbit of the original Russian Sputnik satellite by listening to its Doppler shift (this technique was recently used to locate flight MH370 by measuring the Doppler shift of its telemetry signal). After doing that, they realized that this calculation can be reversed: geographic coordinates could be obtained by lmeasuring signals from a constellation of satellites in known orbits.

Comment: never cross the unions (Score 2) 183

by przemekklosowski (#46794917) Attached to: The Design Flaw That Almost Wiped Out an NYC Skyscraper
The original New Yorker article had a fascinating tidbit: when the architect realized the danger, he arranged to deploy a network of strain gauges to monitor the actual stresses in the building's critical structural nodes. This was done as an emergency, overnight IIRC. Several days later, the data stopped flowing. It turns out that the electrician's union found out that it was done without the union contract and had the wires cut.

Comment: not just flutes: grand piano seized by TSA twice (Score 4, Informative) 894

Polish pianist Kristian Zimerman had his Steinway grand piano seized by the TSA twice: the fist time around they destroyed it, the second time they just detained it for a week: http://en.wikipedia.org/wiki/Krystian_Zimerman
No, they didn't confuse it with a vegetable---apparently Zimerman recently modified his instrument and the piano smelled of glue. As a result he ended up travelling with just the mechanism, fitting it by hand to the boxes at concert halls he plays in.

Comment: Re:Governor Appointed (Score 1) 640

You clearly have no idea how the current, very successful public funding of science works. The model that we had since WWII is based on public funding via competitive, peer-reviewed grants. This review function is crucial and indispensable in order to insulate research from political and even social pressure. Again, the idea is that the public funding goes into a pool, and the researchers compete by submitting their proposals to an independent body of their peers who select most promising projects based on their expertise in the field. The problem with the Nebraska situation is that apparently their legislature ignored the independent review phase and directly allocated money for a custom-made proposal that fits their preconceived notions.

Comment: Re:how much does it cost to research? (Score 1) 166

by przemekklosowski (#43348955) Attached to: What Does It Actually Cost To Publish a Scientific Paper?
Why do you think a publication charge is unjustified and does not add value? Clearly the peer-review and editing process are useful and necessary. We're just arguing over how to collect it: the old model is distributing the costs in a not very transparent way over the journal subscribers, whereas the new one charges the publishing author. I think the new system is more transparent and fairer.

Comment: Re:Writing LaTeX directly is often unnecessary (Score 1) 99

by przemekklosowski (#42916311) Attached to: Collaborative LaTeX Editor With Preview In Your Web Browser
You got this backwards--you are talking about the TeX output, which is of course fixed for a specific format, with specific fonts at specific resolution---and TeX is still better at that than most anything else, by properly handling kerning, rivulets, math layout, orphaning, header/footer layout, indices, etc..

A flexible TeX based system would re-run TeX when the layout changes. Can it be done quickly enough with modern technology? probably yes. Is it worth the trouble? I think the market has spoken and the perceived improvement was not enough to justify the trouble.

Comment: There are practically no socketed ARM chips! (Score 1) 1009

by przemekklosowski (#42102153) Attached to: Is Intel Planning To Kill Enthusiast PCs?
The article is confused about ARM chips, which are practically never socketed. It wouldn't make any sense because ARM CPUs are highly integrated---they tend to include on-chip equivalent of North Bridge, South Bridge and many peripherals such as video hardware, USB, Ethernet, I2C, serial and parallel I/O ports, timers, counters etc. In fact, that's the main problem with Intel in the embedded and enthusiast market: it's hard to make a small/low cost platform like Raspberry Pi because you need an expensive CPU... _and_ the chipset and peripheral chips. The cost difference is staggering---there are ARM microcontrollers that cost less than a dollar (admittedly, not the ones that you can run Linux on, due to lack of virtual memory, and small flash/RAM).

Comment: Re:Incidentally... (Score 1) 633

by przemekklosowski (#41458867) Attached to: Beer Is Cheaper In the US Than Anywhere Else In the World
The Reinheitsgebot isn't such a blessing you make it out to be. Of course it prevents commercial drek laced with oil refinery products, but it also excludes lambics and other flavored craft beers (Midas Touch, blackberry witbier, etc, etc). I really like the beer selection here in the US, with educated public rewarding small craft breweries who put out surprisingly good product.

Comment: Explaining version control (Score 1) 383

by przemekklosowski (#41458735) Attached to: Ask Slashdot: Explaining Version Control To Non-Technical People?
If you ever saved a file under a name such as mypage.html.Jun12 or, worse, mypage.html.old, you basically used a ghetto Version Control. You already agree that it is useful, so let me show how easy it is to do it properly, in a way that will remember everything about who, when, and how changed every file, and will prevent accidental overwrites and editing conflicts.

Comment: Correction: USADA claims to have some evidence (Score 1) 482

by przemekklosowski (#41131067) Attached to: Lance Armstrong and the Science of Drug Testing
It's not quite right that USADA relies entirely on rumors. Their spokesman claimed that they have blood test results that can only be explained by blood transfusions, which are classified as doping, are illegal and were denied by Armstrong. I am just repeating what I understood---please correct if you can.

Comment: secure BIOS confusion (Score 1) 141

by przemekklosowski (#41131015) Attached to: NIST Publishes Draft Guidelines For Server BIOS Protection
So, for starters, people appear to confuse secure boot functionality in UEFI with secure BIOS upgrades. The former is required by new Windows 8 hardware profile and is provided as specified by the UEFI standard. The latter is what the NIST spec is talking about---to prevent firmware malware attacks. The idea is simple---during normal operation BIOS is readonly; firmware updates write the new image to a temporary area, and upon reboot the old firmware takes over, realizes that there's a new firmware available, cheks the crypto signatures to ensure the provenance of the bew image and flashes it if they're OK. Unfortunately, there's no single implementation and AFAIK no common signing scheme---this stuff is proprietary and board-specific. NIST spec might make it saner, by requiring conforming implementations. Does it prevent firmware exploits? Not quite, because there are option BIOSes that reside on PCI cards and such, and AFAIK they are not covered by the BIOS spec. Is it better than a jumper solution proposed here? I believe so: I don't want to go back to the old days of having to crack open the box and boot DOS from floppies; they may work for a single machine or two but are not scalable for realistic largish deployments.

Comment: cheap microscope (Score 1) 118

by przemekklosowski (#40286245) Attached to: Ask Slashdot: Advice On Child-Friendly Microscopes?
Ebay has inexpensive stereo microscopes resembling this one: http://www.ebay.com/itm/20x-Stereo-Microscope-for-Gem-Coin-Stamp-PCB-Hair-/140757697961?pt=LH_DefaultDomain_203&hash=item20c5d005a9 I have a similar one that I got new for around $40. The magnification is a modest 50x, and it has fairly short focus length and depth but it serves well for electronic and mechanical repair and minor surgeries (splinters, hang nails)

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