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Comment Re:It's FREE! as long as... (Score 1) 744

I'm definitely willing to say that I have had bad experiences with Ubuntu upgrades breaking things in the past, mostly in the way of my monitor set up.
However, the 15 minutes it takes to get three monitors each with virtual desktops back up and running vastly outweighs the Windows alternative of one giant screen with no virtual desktops.
I also don't know how anyone familiar with package repository systems can see that as anything but a huge time saver with respect to an operating system like Windows.

Very truthfully, cost of an operating system isn't that important to most tech-savvy people. If I want to use Windows 7, I can either pirate it, or get a free student copy. There is some time investment in getting a Linux setup that works for you, but after that's done, you can be far more productive than you ever would be with Windows.

Comment Re:Better than they need to be? (Score 2, Informative) 63

It says in the article that one of the project goals was to be able to see Saturn's rings, and I know personally that one can see Saturn's rings with a fairly small telescope.
(Of course it depends on the orientation of Saturn and its rings, but assuming they are ideally situated, I don't see why someone wouldn't be able to see its rings, although IANAA)

Comment Better than they need to be? (Score 2, Insightful) 63

An interesting benefit in living in poorer countries is that there is far less light pollution.
Maybe they could make these even cheaper by making some of the optics smaller (reducing the aperture), since something good enough to see Saturn's rings in rural America should be far more capable in an area with almost zero light pollution, like rural Africa.

Comment Re:Sign me up... (Score 1) 681

I think it's important that this NEVER happens.
Would it be convenient? Oh sure, definitely, but that's when people start clicking on things they don't know, and accidentally installing viruses.
Central repositories provide much more security, and if users have to take time to add the application's repositories to their own, or compile the software, maybe they'd think twice and make sure they aren't just downloading some sort of malware.

Comment Re:A-stable multivibrator (Score 4, Informative) 364

There is a great little circuit for something called a "Drawdio" http://web.media.mit.edu/~silver/drawdio/ that kids really love, basically it's an astable 555 that makes a noises with pitch proportional to how long they draw pencil marks. (it's a bit hard to explain quickly, just try the video on that website)
I teach middle school aged kids electronics at a local workshop, building things such as that, and I can tell you it's very doable to make projects for cheap that kids can build and understand.
The main issues that I have found is the board on which you lay out projects. Breadboards are expensive, and not permanent. PCBs don't allow kids to experiment with their own circuit designs, and unless you are going to take the time and money to let them design their own boards that might not work and then etch them, it's more trouble than it is worth. We use a more traditional breadboard concept that is just an actual, wooden board. Then we have kids use copper tacks and strips to lay down the circuitry, and then they solder things directly to that.
As other people have mentioned, soldering irons are a bit annoying, and a couple kids might get some mild burns, but as long as you don't mind the initial cost, it's totally doable.
One of the great things about the drawdio project, is it allows you to hook it up to a oscilloscope and show the kids more about sound, or hook the piezo speaker up to a computer and run some FFT software, so they can see and hear how the resistance changes the pitch.

Other things to look into are basic transistor circuits, things with opamps, counters, or things with binary to decimal or binary to seven segment LCD chips.

Comment Re:Woo Hoo!!! (Score 2, Informative) 173

Just wanted to mention there is a mutli-platform (okay well, Mac support is still iffy :/), LANable, fun, RTS engine called Spring. It's FOSS, of course, and lots of mods are available for playing online.
Don't mean to preach or anything, I was just really happy when I found a game I could play at LAN parties with my friends without having to reboot. http://springrts.com/

Comment Re:rabit from the moon (Score 3, Informative) 196

Well, let's say 1 Library of Congress is about 20TB, a measure of information. If we want to convert that into Rabbits * arc length, a unit of temperature * arc seconds, we can use the laws of entropy.

We know that entropy=k*ln(O) where k is the Boltzmann constant and O is the number of microstates of the system. If we really wanted, we could express the number of microstates as 1 LoC, since both are really just measuring information in one way or another.

Now if you recall temperature = change in heat/change in entropy. The average body temperature of a rabbit is about 312 degrees kelvin according to google.

To get a change in entropy and heat, we can look at both over an arbitrary time step t, so 312 K [one rabbit]=(heat/t)/(k*ln(2TB [one Library of Congress])/t)

Solving for one Library of Congress, we get one Library of Congress = e^(k*heat [in joules]/312 degrees K)=e^(4.4252x10^-26 joules^2/(degree kelvin)^2)

Now assuming a rabbit is about 0.2 meters in diameter, at a distance of about 384,000 km, that's about 3*10^-8 degrees.

So, putting that all together, the conversion factor is about e^(4.4252x10^-26 joules^2/(degree kelvin)^2)*1.1*10^5 arc seconds.

Hope that clears things up for you!

Comment Re:The place you want to visit (Score 1) 259

I second this recommendation. Obviously the poster has been there if they linked to it, but they also clearly have not taken advantage of it at all.
Sure, Slashdot is great, but you can sign up on DIY Drones and get much better responses from people with more experience working directly with, well, do it yourself drones.

On another note, I've been sort of working on my own UAV for a little while now. You can get lots of parts from Sparkfun, ranging from the Ardupilot to GPS's to microcontrollers that you can program yourself for a UAV.
The most important thing to consider is cost, and I would say the second is what exactly you want to get out of this project. If you just want the end result, it makes more sense to go with a prebuilt autopilot such as the Attopilot or Ardupilot, if you are doing it for the experience, it might make more sense to look at the Paparrazi project or just kind of work it out yourself. If you really want you can even build your own airframe, wireless infrastructure, and solder up all the boards yourself.

So really, it's hard to give you any advice based on what you've said so far. There are hundreds of ways that you can take the project depending on just what you want, but I would say that DIYDrones is the best place to start, the people there are pretty friendly, and if you describe just what you want, they'll definitely be able to help you out.

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