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Comment Re:Release some educational rap videos. (Score 1) 138

Speaking of evaporation, I used to work on a custom bill-of-material system for radiopharmaceuticals. We couldn't use an off-the-shelf system, because the active ingredients have short lifetimes. That meant that we had to track the precise age of the product in order to calculate the proper doses. For example, iodine-131's half-life is roughly 8 days, which means you lose 8% of your product a day, while technetium-99m's is a scant 6 hours, meaning you lose 12% every hour.

Comment Re:guilty eh? (Score 1) 964

"Lying on his family room floor with assault weapons trained on him, shouts of "pedophile!" and "pornographer!" stinging like his fresh cuts and bruises

I have to ask what's the point of this? Does the DEA shout "Dealer!" when they bust down doors? Why the intimidation? It reminds me of Bradley Manning's treatment. Can one sue for excessive force during an arrest, justified or not?

Comment Re:level (Score 2) 456

The vast majority of my learning has been through participation in discussion. I found books too dry for learning, nor did I retain much from them. I also didn't handle lecture well, because things go in one ear and out the other.

I don't think you actually disagree with me. You note you didn't handle lecture well, and thats what I criticized (a guy talking and you just taking notes.) I agree with discussion being a powerful learning tool. It's one of the most powerful tools for learning, but one thats hard to afford (you need extremely small student group for each teacher to implement effectively in the classroom, or have direct conversations with a mentor.) It's also the reason why study groups are effective.

Lectures work best if you take notes, especially by hand. Note-taking prevents information from going "in one ear and out the other" because, like discussion, you activate more areas of your brain as you take notes; think of it as having a discussion with your notebook; I don't know anyone who can write as fast as a lecturer talks, so you have to be constantly deciding what to write down instead of letting your mind drift around. This doesn't just work at school. When I go to a baseball game (for pleasure, anyway, rather than to schmooze with clients), I try to get a scorecard and track every play. I've found that I remember the details of those games much better that the ones where I kicked back and drank a beer. (And I remember *any* game that I actually attended better than the ones I watch on TV, so try to actually attend class, not depend on someone else's retransmission.)

Baseball scorecards are optimized for taking notes on baseball games. Likewise, at a lecture you should use Cornell Notes, a tools optimized for taking notes at lectures. There are thousands of web site dedicated to this, so research it yourself at

Finally, if you don't believe me then look at what others have to say. For example, claims (in bullet point 3) that "Taking notes by hand instead of typing them, will help you retain the information more effectively, as the pressure points activated by holding a pen are linked to the creative and memory centers of the brain." If that sounds a bit unbelievable, research reported at backs up the claim.

Comment Re:have your own servers (Score 2) 125

This incident illustrates once again why you need to put your stuff on your own servers and not someone else's.

Well. Or put your stuff on your own servers as well as someone else's. Cloning your services into various clouds isn't insane as a tool for handling some types of unplanned scaling requirements or some types of unplanned outages. Relying on those clouds introduces risks that were just demonstrated.

It's probably worth noting that EMC makes a cloud storage product called Atmos with an API essentially identical to Amazon's S3 service. The main difference is that the HTTP headers start with x-emc instead of x-amz, so a properly written application running on non-Amazon servers could switch fairly easily between the two for load balancing or redundancy.

Comment Erase your phone (Score 4, Informative) 525

According to, you want to own an iPhone 3GS or later.

You can remove all settings and information from your iPhone, iPad, or iPod touch using "Erase All Content and Settings" in Settings > General > Reset.

When you opt to "Erase All Content and Settings," the process can take up to several hours. The time this process takes will vary by device:

Devices that support hardware encryption: Erases user settings and information by removing the encryption key to the data. This process takes just a few minutes.
Devices that overwrite memory: Overwrites user settings and information, writing a series of ones to the data partition. This process can take several hours, depending on the storage capacity of your iPhone or iPod touch. During this time, the device displays the Apple logo and a progress bar.

Comment Re:Nope (Score 1) 361

1. How do you deal with hard-linking to directories (i.e., a VIDEO_TS directory or higher level directory)?

Just about everything I own has been ripped to a single file; if if I needed to, I'd create a directory (they're small compared to media files) and hard link everything in it.

2. How do you find and delete every last hard link when you want to delete something?

Why would I want to delete something? Storage is cheap. (OK, let's assume I discover I've got a Tracy Lords porn flick, illegal to own since it was discovered that she was underage when she made them. In that case, you just search for everything with the same inode number (or the NTFS equivalent) and unlink them as you find them. It shouldn't take any longer that searching for and deleting dangling symlinks.)

3. What's wrong with leaving dangling symlinks upon deletion, and then running a script to clean them up?

I don't delete stuff, I just occasionally re-tag. Using hard links means there's no "privileged" copy, whose deletion would create dangling symlinks.

Comment Re:Nope (Score 1) 361

I use hard links. Everything by Ridley Scott is in the movies/directed_by/Ridley_Scott directory, everything based on a Phillip K. Dick story is in the movies/story_by/Phillip_K._Dick directory, everything from 1982 is in movies/year_released/1982. I can delete things at will without fear of suddenly creating dangling symlinks.

Comment Re:Experiments vs Technology (Score 1) 225

My one strong caveat (I did say it was worth a SECOND look - which happens here) - once you identify a technology that might be of interest, the question should always be, "Is this worth it (time, money, pedagogy, etc.), and can I do the same thing low-tech?" This is where you cut out the "It's just like real life, but ONLINE!" instinct that sometimes pops up.

Even if the same thing could be done low-tech, it may still be worth adapting into high-tech - but make sure your reasons are good. [...]

That reminds me of

Amish settlements have become a cliché for refusing technology. Tens of thousands of people wear identical, plain, homemade clothing, cultivate their rich fields with horse-drawn machinery, and live in houses lacking that basic modern spirit called electricity. But the Amish do use such 20th-century consumer technologies as disposable diapers, in-line skates, and gas barbecue grills. Some might call this combination paradoxical, even contradictory. But it could also be called sophisticated, because the Amish have an elaborate system by which they evaluate the tools they use; their tentative, at times reluctant use of technology is more complex than a simple rejection or a whole-hearted embrace. What if modern Americans could possibly agree upon criteria for acceptance, as the Amish have? Might we find better ways to wield technological power, other than simply unleashing it and seeing what happens? What can we learn from a culture that habitually negotiates the rules for new tools?

That's an article I revisit from time to time, to remind me to cut out the "It's just like real life, but ONLINE!" instinct.

Comment Re:Get offline and do experiments (Score 1) 225

How about nobody is allowed to post on /. without first building their own computer? I'll be generous, you're allowed to simply strap a uC to a board, but you do have to write your own bootstrap routine. Bonus points for doing it properly and using discretes. Now, back to physics, it's about measuring it yourself, and understanding every step. Video camera + crazy software is going to take a long time to understand (care to explain motion artefacts captured by a video camera?). Start from Galileo, work up.

I've written several bootstrap loaders. Some were for minicomputers (and I've still got the paper tape somewhere), one was for 8086 5-1/2 floppies which would display ASCII animation if you rebooted your PC-XT with the floppy in the drive. (Hey, you kids, get off of my lawn!)

Comment Re:Get offline and do experiments (Score 1) 225

In college, there were some Chem E. guys in my dorm, who'd make nitrogen triiodide for pranks. Paint it on a door frame and wait for someone to close the door. Paint it on the shoe soles of someone taking a nap. Paint it on a light bulb and wait for someone to turn on the light. That last one almost got them killed, someone had just opened a big care package of homemade cookies which then got covered in glass shards.

There was a guy who worked in the physics department machine shop. He'd save long magnesium shavings from the lathe for various "experiments". Late one night we filled a balloon with hydrogen, tied a foot-long magnesium thread to it, lit it, and turned it loose. Then we turned on the police band scanner and listened to the UFO reports about bright lights floating in the sky, then disappearing in a flash and a bang.

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