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Comment I've done this (Score 4, Informative) 235

I have done this for a grant-funded historical map digitization project at a university library. We used a $40k large-format scanner (from Betterlight) which can scan the whole item laid out flat. Trying to stitch together camera images will result in distortion across the image—if you didn't need to distort it, you wouldn't need special software to do it; you could just line the pictures up.

But even once you have image files, there's about zero chance you can just replace Google Maps' tiles with your own and expect geotagged stuff to line up where it should. If you have a finite number of places of interest, you could manually locate them on each map and then try to distort each map to align, but if you expect arbitrary geolocations to need to be right, give up. Non-satellite/GPS-based maps are examples of practical cartography, not theoretical. They will be even less perfect than you think, no matter how professional they appear. Or do what we did: keep the geotag display on Google's maps, but show your historical map of the same general region side-by-side and allow the user to calculate the precise correlation in his own brain.

Comment Hair exemption (Score 1) 288

Thank god for my ponytail. It's a Get Out of Jury Duty Free card. No prosecutor wants a long-haired, unmarried engineer with no kids on his jury. Apparently we ask "why not" too often and have unreasonably high standards of evidence, plus it's harder to move us with the old "Won't somebody please think of the children!" line. Fine by me.

Comment Re:On Hybrid Vehicles (Score 1) 594

Good choice on the TDI. My situation re: hybrids is like yours but even more so. A Prius is a pretty heavyweight solution to what's really a pretty simple problem—if the problem is saving money, used wins, and if the problem is saving the planet, reliable used wins unless you drive a lot because it's already manufactured and the gas mileage difference isn't necessarily that huge. I put more miles on my bike than my car, so I chose a little Chevy shortbed truck that gets a decent 30 mpg, with the added benefit that, unlike a VW, it has almost nothing non-essential to break. Power nothing, manual transmission, and practically no electronics in it. To be honest, I'd probably have come out ahead in both dollars and environmental resource usage vs. a Prius if I'd bought whatever was the least efficient small car of the 90's. Perhaps a Prius makes sense for people who commute in traffic a lot.

Comment Institutional repository? (Score 1) 438

What kind of documents are they? If they're mostly text and you want versioning, the only drawback to subversion is getting people to learn the tools, but that might be too much.

If they're archival/static documents, an institutional repository could work. Something like DSpace isn't that hard to deploy and will provide basic archival and search features.

The middle ground between those two solutions is probably what you want, though. Everyone I work with uses SharePoint for that, and I hate recommending proprietary lock-in.

Comment Re:Larry effect again? (Score 1) 361

Time Machine serves two purposes at once: snapshots and backup. Having snapshots available doesn't help when the disk dies or gets corrupted. I suppose you could still copy everything to another disk and then use the ZFS snapshot features there, instead of using HFS hardlinks, but copying to another physical disk still needs to be part of the process.

Comment Re:First collision (Score 1) 456

>>>Each satellite massed well over 1,000 pounds."

That's only if you're using the less-common FPS sub-version of English units (where pounds are mass units and poundals are force units). According to the gravitational FPS system (where pounds are force units and slugs are mass units), which is what I learned in high school at least, each satellite's mass is at least 31 slugs.

(That's close to 32, which is the approximate scaling factor between mass-pounds and force-pounds due to Earth's gravity acceleration at sea level being about 32 ft/sec^2, but it's just a coincidence. 31 slugs * 32 ft/sec^2 =~ 1000 mass-pounds, which is the "weight" of the satellite. Any good geek ought to see that quickly, though, since 32 * 32 is the familiar 2^10.)

And this is why SI exists.

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