Sometimes work gets in the way of scouting. Maybe that’s a bad way to put it. Sometimes I don’t have as much time to put towards scouting as I would like. Today was one of those days. Don’t get me wrong, I really like my job. I get paid to work on interesting problems with a great group of people that I like and respect. It just doesn’t help we when I’m trying to complete the 100 Days of Scouting challenge. But being unemployed wouldn’t really help either, so I’ll take it as it is!

In order to celebrate my birthday tomorrow DARPA is offering a $40,000 prize to the first person or group of people that can find 10 red balloons. DARPA, aka the Defense Advanced Research Projects Agency, is not just looking for any ten red balloons, but ten specific red weather balloons they have positioned around the United States. They are calling it the DARPA Network Challenge to hide the real reason for the contest, because the “Arlen is so awesome we want to give away money to celebrate” was too obvious.

10 99 Luftballons

So there you go, 10 AM tomorrow go win $40,000 for my birthday.

Find the location of these 10. I doubt they will be this close together.

OK, so it isn’t really for my birthday, but to celebrate the 40th anniversary of the internet. More specifically the ARAPANET, the internet’s predecessor.

To mark the 40th Anniversary of the Internet, DARPA is hosting the DARPA Network Challenge, a competition that will explore the role the Internet and social networking plays in the timely communication, wide area team-building and urgent mobilization required to solve broad scope, time-critical problems.

Still, it is a good reason to use lots of things DARPA has helped develop: GPS, the internet, maybe some robot minions, or even a Predator if you have one to help with the search, which would be way cooler than the social networks other groups are using.

Spinal Tap Engineering.

Today’s XKCD made me laugh out loud. Some problems are marketing and sales problems, not engineering problems.

Spinal Tap Engineering (Click to see original)

Units of measure are sooooo unnecessary.

For the Thanksgiving feast this year I was responsible for the turkey, so I had the opportunity to brine a turkey again.

Turkey. Representative of typical results.

This is where we start to run in to problems with the assumption that osmotic pressure is the mechanism behind turkey brining. We know from the brine recipe that there is about 1/2 cup of salt per gallon of water, which results in a 1.12 M solution. For comparison, physiological saline (0.9% NaCl) has a molarity of 0.156 M. If we assume turkeys have the same salt concentration as people, that leaves a difference between the brine and the turkey meat of 0.964 M. The big problem here is the direction of the offset. The higher concentration is in the brine, not the turkey meat. The pressure is in the wrong direction to force more H₂0 into the meat.

It turns out I’m not the first to ponder this question, and there is an alternate hypothesis.

The real answer has to do with the shape of proteins. In their natural state, the muscle cells are tightly bound within their protein sheaths—this doesn’t leave much room for excess water to collect in the meat.

But as anyone who has ever made sausages or cured meats knows, salt has a powerful effect on muscles. A 6% solution of salt will effectively denature (read: unravel) the proteins that make up the sheath around the muscle bundles. In this loosened, denatured state, you can now fit more water into those muscles than in their natural state. Even better, the denatured proteins in the sheaths contract far less as they cook, therefore squeezing out much less moisture.

So it turns out that denaturing proteins has a much bigger role in the effect of brining turkey than osmotic pressure.

I don’t think the knowledge will help you make a better turkey next year, but if you need something new to talk about at the Thanksgiving table, it might due the trick. If the guests fall asleep you can always blame the tryptophan.

A little bit of applied mathematics for your next “number of M&M’s in the jar” contest.

From Make

Has it been a month already?
If it wasn’t for Twitter, you guys would be wondering if I was still alive!

But just to make it up to you, here is an anamated short about young Oxygen on the playground of the Periodic Table.

Things that bother me about some of my favorite TV shows all wrapped up in a four frames from PhD Comics

I know this blog has become a never ending stream of videos and comics lately, but this is too good to share. Maybe it rings true to me these days because I just recently added myself to the ranks of the iPhone users.

I love my phone. I hear that admitting you have a problem is the first step to recovery, but if anyone wants to tell me their favorite iPhone app in the comments, I wouldn’t mind!

The latest XKCD comic hits on one of my favorite subjects. I am sharing it with you now. These two statements are correlated.

The first rule of street-fighting mathematics is…

The first rule of fight club is you do not talk about fight club

Math is always portrayed as exacting and calculating, but there is a great need for those that deal with numbers on a regular basis to also have a sense for approximate answers. Throughout engineering school it is often referred to as “back of the envelope” calculation. Quick and dirty approximation that gives a sense of the exact answer.

A colleague pointed me to a class called “Street-Fighting Mathematics” over on the MIT Open Course Ware site. MIT OCW is a site with lecture notes, readings, exams and videos from quite a few classes. Now you have no excuse for sitting around doing nothing on a Friday night! Street-fighting Mathematics is taught by Sanjoy Mahajan, and it looks pretty well put together.

The course description reads:

This course teaches the art of guessing results and solving problems without doing a proof or an exact calculation. Techniques include extreme-cases reasoning, dimensional analysis, successive approximation, discretization, generalization, and pictorial analysis. Applications include mental calculation, solid geometry, musical intervals, logarithms, integration, infinite series, solitaire, and differential equations. (No epsilons or deltas are harmed by taking this course.)

Seems to be the thing everybody should review every once in a while. Here is your first assignment, now get to work!