Category: General

I thought I had lost my USB drive today. I was in a panic. I went back to the place I had lunch and it was sitting there on the chair. It must have fallen out when I went into my pocket. I know I’ll lose the rubber cap on my drive eventually, but I wasn’t thinking I’d lose the whole thing.

I’ve been pretty good about not losing small stuff, although I’ve had a few scares with my iPod and my cell phone.

The USB drive is a whole different level of small. You know if your iPod or cell phone isn’t in your pocket, but you can’t feel a USB drive. I think I’m going to have to resort to wearing it on a laynard or something so I can keep track of it.

On a totally unrelated note….

A Canadian university has banned the use of WiFi on their campus for health reasons. Reason? Possible health risks. Evidence? none. We just don’t know.

Problem is, we can’t prove a negative. We can never show that there is no harm to radio waves. However, we haven’t found any link between radio waves and anything. To quote the University President, Fred Gilbert

“All I’m saying is while the jury’s out on this one, I’m not going to put in place what is potential chronic exposure for our students. Admittedly that’s highest around the locations of the antenna sites and the wireless hot spots, but those are the places people tend to gravitate to because they get the best reception,”

Lets look at the wireless internet for a moment. WiFi inhabirts the 2.4ghz part of the spectrum. Its shared with microwave ovens, amateur radio, and other public airwave things like baby monitors. Most WiFi acess points operate at less than 1 watt of power. Often, significantly less than 1 Watt. 100mW is common (0.1 Watt). To put this in perspective, standard incandescent bulbs can use 50-125 W of power. EM radiation also behaves according to the inverse square law. That means that the intensity of the EM radiation decreases by a factor of 4 every time you double the distance between you and the object.

Most computer users are easily several meters from a wireless access point (but very close to their computer, which produces EM radiation anyhow. If you are reading this on a CRT your standing next to an emitter of EM radiation which is probably more powerful than a wireless access point.) You are usually in closer contact with a cell phone, which will expose you to more effective EM radiation than a wireless device if only due to proximity)

There is dangerous EM radiation. In particular gamma rays and x-rays. However they have frequencies well above that of visible light, and 2.4ghz is well below that. NOTHING has shown a link between incidental exposure to radio waves and any detrimental health consequences. If such a link exists, it probably should be considered so small as to be swamped by the benefits that wireless Internet access brings. It it were large, it should be obvious.

Having a college campus without wireless internet is in the year 2006, like having a college without a library.

Last week I posted about testing milkshakes or salt in the X-Ray Diffraction machine here in the geology dept. Depite the allure of milkshakes, I went with salt just because it was so much easier.

Salt, and by that I mean table salt, is just NaCl. Sodium Choloride. Halite. The salt I tested was sea salt which was created from the evaporation of sea water. The stuff I purchased was made in France on the shore of the Mediterranean Sea. I fully expected the vast majority of what was in the salt to be halite, but I also assumed there were to be some other bits of stuff in it as well. The dissolved components of sea water are mostly sodium and chlorine, but there are lots of other trace things as well (Mg, SO-, Ca, K, etc). As the water evaported, I assumed other minerals would grow in the evaporate, and was what I wanted to determine.

I started with some very coarse sea salt. I had to choose coarse sea salt, because the finer salt has an additive to prevent caking. The additive might have screwed up the reading, so I got the coarse grain salt and ground it up with a mortar and pestle.

The powder is then placed on a special slide with an indentation on it to hold the powder.

Making the powder is important because our XRD machine is a powder XRD not a crystal XRD. With powder XRD is much easier to prepare samples.

The actual XRD unit itself is pretty small, considering how big they used to be:

The slide with the powder is placed in the machine. The machine then shoots a beam of X-Rays at the powder (created from copper) and rotates the slide with respect to the beam over a set angle (in my case 2θ was from 15 to 60….its 2θ, not θ. See Bragg equation.)

The end result, is a series of measurements taken at different angles which measure the intensity of the diffration of the sample. I ended up with a graph that looked like this:

What is interesting about this a) there were no other trace minerals, and b) the peaks were uniformly off from the peaks which were expected from Halite. The current guess is that the other elements or at least some of them, rather than forming new minerals were substituted into the Halite. This increased the spacing in the crystal lattice and increased uniformly the angle at which diffraction occured.

The problem is, if that is the case, that should be the case with most all Halite which is almost always created from evaporating sea water.

I might run some more tests on other samples to try and find out what the deal is.

I now have rotating images at the top of the site. They are all original photos taken by me. I may put up some more if I can find photos worth putting up. Some of them have some minor flaws, but I’ll try to correct that soon.

I, like most people now days, have a USB drive that I carry with me. I got mine a few years ago and like all cutting edge users, paid a lot for what is now a piece of crap. I’ve been using a 128mb UBS drive, and while its fine for storing simple things, was leaving me feel inadequate and wasn’t able to do the cool stuff I wanted to do.

I went to Micro Center (best computer store in the Twin Cities) and got me a 2gb USB drive from Corsair. Its got rubber armor and its water resistant, and acording to Maximum PC, is the best USB drive available.

What do you do with 2gb of memory that you can carry with you all the time? You install portable versions of the applications you use all the time.

I am writing this post off of a portable version of Firefox that is on my USB drive. I also have versions of Thunderbird, Abiword, and OpenOffice running. Basically, all the core applications I use can now run off of my USB drive so they are always with me and my settings never change. All of the applications I have installed, plus all the stuff from my other USB drive, are only taking up about 17% of the 2gb drive. Nice.

If I was really adventureous, I could even run an OS off of the USB drive.

If you want to play around with some portable apps, go to PortableApps.com.

Note: you can only install open source applications as of now.

Having this ability is really, really nice. This is one of those things that really changes how you use a computer. Its that big of a deal.

I just walked past a poster on campus that said banks loan 17x more to cars than they do to students.

I rolled my eyes.

I’m not even sure where to start on this one:

1) Banks don’t lend money to cars. They lend money to people to buy cars.

2) Implict in the poster is the claim that people are morally superior to cars. People are more important. See comment #1.

3) The real thing to compare isn’t people and cars, but cars and education. Or better yet, transportation and education.

There are a lot of things about education, higher education in particular, which people accept as fact which are not. The primary one is that getting an education will increase the amount of money you make in your life.

There is indeed a strong correlation between getting an education and the amount of money you make in your lifetime. However, and if you are indeed educated and have had stats 101 you should know this, correlation isn’t causation. There is good reason to believe that people who go to college are the ones who probably would have been more successful, regardless of college. Especially if they are in a line of work which has nothing to do with what they studies (which is damn near everyone) I know some very bright people who never graduated college and do quite well. I also know some idiots with degrees.

More over all educations are not created equal. We are currently churning out loads of people with useless degress. I can’t tell you the number of political science, sociology, and psychology majors are running around the UofM campus. The number of these kids who actually end up working in this field is very small. The college you attend, and your field of study are enormous variables that are completely absent in any generic discussion of education.

Most discussions of higher education almost universally center around getting more people a college education. In reality, we probably have too many people in college. One of the primary reasons why the costs of education is going up so fast is that the supply is pretty much constant, where as the demand keeps going up. College takes people out of the workforce for 4 years. That is the primary reason for college.

When I have this discussion with people, they usually resort to things like meeting new people, hanging out and other non-academic things. These have nothing to do with college, but leaving home for the first time.

Back to the original point of banks and lending. Cars, quite frankly, are a better investment. You at least can sell them. If I were to loan someone money for an education, which is not a bad idea, I’d tie the loan to things which no one ties education loans to today: what will your field of study be, grades, what college you will be attending, etc. I’m not going to waste money on someone who muddles through an american studies degree. I’m going to give it to the kid going into engineering.

And also, there are a lot more cars than students.