Daylight

Because I was up before sunrise and missing the sun, I got to wondering when it would rise.  One thing led to another and I graphed the sunrise and sunset times for 2012.

Two questions:

1. Why isn't it symmetric about the date or time axes?
2. What are all the discontinuities? 

Inquiring minds want to know.  In any event, it seems I'll be up before sunrise for another month and a half, sadly.

Points Plus Values of Stout Food Items

I was shocked, I say, shocked when I computed the Points Plus value (pp) for one of my favorite Stout foods: the delightfully sinful raspberry scone.  Only, I didn't know it was sinful before.  It is so little and innocent looking.

14 pp!!!  That's right, the little scone that fits in the palm of your hand is nearly half a day's worth of points.

I decided to look up some of my other foods*, and put them on my blog for reference.  This should keep me honest at the food cart.

Jumbo Cookies (any type) ........... 5 pp

12 oz pop...................................... 5 pp

Raspberry scone ........................ 14 pp

I wish they had information for the snack items at the food carts as well.  For example, their to-go items like salads, sandwiches and wraps.  That's what I normally eat for a quick lunch if I forgot to bring my own. 
 
* Source: "Making Healthy Decisions", 20110-2011 Nutritional Information for Foods Served in the Commons and North Point Dining Operations, University Dining Services (www.uwstout.edu/dining)

How to create a reviewable, scientific document, in html-compatible format

Though not the only way, this is a working method for creating a document written in html-compatible code.

• For equations:  Download "Math Cast" and create your equation.  Your saved file can be opened in a text editor to grab the html code.  (It is actually MathML, but will work in html editors.)
• For images (of diagrams, apparatus, etc.):  Upload your image to flickr.com.  Once uploaded, the image has its own web address and html code.  Use the "share" option to grab the code. 
• For text:  Just type!  Use a text editor.  Insert your equations, diagrams and images using the grabbed code previously discussed.

For LaTeX junkies, all of this can be done with WinEdt or a similar TeX editor.  There is a steep learning curve, but the results are stunning. Why use LaTeX instead of Word or similar?  Two "words":  html code.  You *can* get html out of Word, but it contains a bunch of extraneous gobbletygook that is inevitably buggy and cumbersome.  

If you want to share your document in html, use the method in this post (or LaTeX, for more formal, "camera-ready" documents).

What's in your document?

Awhile back, I posted about how to insert equations into google documents.  The link I blogged about is no longer functioning so I needed to find another way, and a better way.  A way to insert equations that aren't images only, but editable pieces of information that flow seamlessly into a document. 

I haven't.

There is some interesting information out there regarding the paucity of html-compatible mathematical and scientific communication.  I'm running into it because of a calibrated peer review project I'm part of at Stout.  I wanted to enable my students to post real homework solutions for other students to review.  The sad thing I'm finding is that it is easier for them to hand-write a solution, scan it into a digital PDF document, post it to flickr or similar as an image and link to the uploaded image!!!

Where are digital chalkboards when you need them?  We have those, you say.  Yes, we do.  But, trying to share what you've written with anyone on the web is difficult, unless you are sharing an image.  Why can't we share scientific writing like we can share text?  Something editable by groups, easily typeset, etc?

I'm calling it.  Whoever develops this technology will be a physicist.  And it will revolutionize communications and networking yet again.  Web 4.0, that's my prediction.  A system that would allow communication in this way would not just be for scientists, mathematicians and engineers.  If you can draw a diagram, you can also collaboratively share artwork, photography, logos, anything you can scrawl into the sand, or paint on a wall.

Ok somebodies, get to work, please.  We educators are waiting on you.

My dad writes these great letters to the editor in the Rapid City Journal. I repost here so those with a similar sense of humor can enjoy them too.

One thing newspapers thrive on is the reporting of errors. The spill of oil in the gulf is perhaps the latest most egregious example. But why do we make so many errors? Perhaps a better question is why do we get things right once in a while?

There are many ways to be wrong or stupid and few ways to avoid error and be intelligent. If all possibilities are equally probable we are doomed to a preponderance of errors. Only by intelligent choice (in short supply) can we skew life away from errors. If you are prone to making long term bets, you should bet that errors would vastly predominate. What smart gambler would bet against human stupidity causing errors?

Consider parallel parking a car. Which is easier, parking or getting out of the parking space? Clearly getting out is easier, because there are many more ways to get out than get in. A physicist might say the phase space for parking is relatively small compared to that of exiting.

Schiller in 1802 said "Life is only error, and death is knowledge."

Yoga Foam

I enjoy yoga. At right is a closeup of a section of my very first yoga mat. It came as part of one of those kits, with the DVD and everything, that you find in your local discount store.

As a materials person, I am intrigued by this structure. I thought I'd share it here.

This mat is probably PVC, wholly or in part. PVC stands for polyvinyl chloride. It is a thermoplastic polymer, a type of plastic. PVC in itself is non-toxic. Without additives, it has the feel of vinyl siding on houses. Many of the PVC products, however, have been softened with the use of plasticizers called phthalates. Phthalate is toxic to humans and other critters. It outgasses for awhile after the softened PVC has been manufactured. (That "new car smell", for example.) Most plastics manufacturers have ceased using phthalates in PVC construction. If you're concerned, ask about the additives used.

All that is well and good to know. However, I always like to find out the microstructure of these beasties. It is fascinating to me to think how the tiny structure has emergent properties at higher levels of complexity. In other words, a monomer molecule of PVC ain't nothing like the real thing, baby.

The aforementioned monomer is a carbon atom with 3 single bonds to hydrogen, and one to chlorine. But there is so much more!

When you get a bunch of these puppies together, they form chains of inert molecules. Multiple chains conglomerate like spaghetti noodles in a bowl. The ability of the chains to slip past one another accounts for the softness/hardness of the material. You can do stuff to change the hardness. Raising the temperature makes it soft. Lowering, hardens it. But there is yet more!

If you bubble the clumps of chains by blowing air through them (think blowing bubbles in your drink with a straw, but with 10 x the force and an 100 x smaller straw), you can create plastic bubbles! Tiny bubbles, everywhere. Like the foam on a glass of milk, the bubbles in plastic form their own structure, depending on a host of factors.

Plastic bubbles don't collapse as liquid bubbles do. Plastics are, after all, not liquid at room temperature. However, they do reshape over time. New bubbles are roundish. Established bubbles are polygon-shaped. Foam is born.

I'm no plastics engineer, but I find this stuff fascinating. Somebody figured out how to blow bubbles in PVC to form foams that stay foamy! Like the yoga mats in their original incarnation. Current mats are made of many different materials, not all of which are plastics.

Next time I'm doing a down dog, I will no doubt be looking at a spot on my mat like the one shown, imagining blowing bubbles in my spaghetti that stay!

It is great to be a geek.

Yes, this is original art, drawn by my dear ole dad. I find him hilarious. This work was actually semi-approved by my brother-in-law, a Lakota Sioux. I say "semi" because I believe he laughed at it and said no words.