Citizen First-Responders… There’s an App For That

This is incredible.

San Ramon Valley Fire Protection District in California is launching an iPhone app that will dispatch trained citizens to help others in cardiac emergencies. Faster response. Greater likelihood of success.

Read the whole article over at O’Reilly.

In all seriousness, ignore, for the time being, any potential legal issues that may exist.

If this type of thing comes to my area, I will gladly volunteer to help out.

OSX Time Machine Backups

Going to get my OSX-geek on for a few minutes. So, feel free to ignore this.

However, if you’re running OSX and using Time Machine and, if, for example, you need to delete some old copies of backups to free up space, there’s a way to do it. I don’t think it’s well-documented though.

While it is possible to have Time Machine simply ignore any give directory, which, of course, eliminates the need to go in and tell TM to delete old backups of it, this isn’t an option in managed OSX environments where a Time Machine backup policy is enforced through Open Directory, Workgroup Manager, etc.

There may also be cases where one needs to free up some space with little risk of loss by deleting older, unneeded backups.

First, the setup:

  • Open Finder.
  • Check on the window’s button bar for an Actions button. Naturally, it’s not labeled as such, but it’s a small gear with a small option button next to it.
  • If the Actions button isn’t there, right-click on the button bar of the finder window then click Customize Toolbar. In the upper right corner of the sheet that appears, there will be an Action button (labeled as such, too). Drag it to a suitable place on the toolbar then click Done.

To delete old backups:

  • Start Time Machine. You may use the Time Machine app in the Applications folder or click the Time Machine icon on your menu bar (if it’s enabled) then click Enter Time Machine.
  • Once Time Machine starts, use the Time Machine Finder windows to navigate to the object and time that you wish to delete. For example, I keep some virtual machines in /Users/Shared/Virtual Machines for which I only need to keep about a week’s worth of backups. So I click through until I’m in that directory.
  • Adjust the Time Machine scroller on the right side of the screen to the date where you want to begin deletion.
  • Click the file or folder you wish to purge.
  • Now click the Action button on the Toolbar then click either “Delete Backup” to delete only the single backup or click “Delete all backups of…” to delete, well, every backup of that file or folder.
  • Click OK when prompted.
  • You’ll need to have administrative access to apply the change.

Now, just wait. You can click Cancel to return to your desktop, but Time Machine will happily start purging old backups of whichever object you specified. Depending on the volume of the data and type of Time Machine backup drive, it could take just a few minutes or even a few hours.


Not elegant, but effective:

while [ 0==0 ]
  s=`echo “$n1+$n2” | bc`
  count=`echo “$c+1” | bc`
  echo -e “$c\t$s”

Threw it together to demonstrate to Boy Wonder how to devise the sequence. Actually, this is the one I started with in pseudocode on the side of the refrigerator then it morphed into the one above to make it work in bash:
  print result
Serves very little practical purpose other than to learn and see the relationship of numbers.

And Now, For Something Completely Different…

I love technology. Click through for more awesome quadrotor video from the U. Penn GRASP lab:

Yes, quite cool. Here are a few ideas:

  1. More quadrotors!
  2. Adjust the flight pattern to combine rotation and all three directions of travel in one or two combined movements instead of many separate movements. This one might be a bit tricker to implement effectively.
  3. Give them the ability to self-dock in a series of charging stations. Probably trivial to make them dock at a particular location (like one of, say, three charging stations). But to have a battery that can be charged quickly enough to be worthwhile — that might be somewhere in the future.
  4. Give them more parts to build larger, more awesome structures — like a shrine to our Robot Overlords.