Teaching?

Today in sacrament meeting I gave a talk. Aside from some nerves, I felt pretty good about it, and the congregants kept telling me it was good, too.

On the way home from church, Jake was driving and he asked me if I ever considered going into teaching. He brought up several things he was impressed with in my talk and also from watching me help Clint and Matt with homework problems as they've needed it.

I have to admit that I enjoy teaching. It's a skill I spent a lot of time honing on my mission. By the time I finished my two years in the Badger state, I felt like I was a pretty competent teacher. Unfortunately, that's when they sent me home.

When I went to get my patriarchal blessing as a 16-year-old, I wanted to hear about my career. I remember insisting to Patriarch Lowe that he tell me what work I would be involved in. The description in his blessing was vague, and I left feeling more than a little let down. No specific direction toward scientist, physician, artist, psychologist, or anything. It just said that I needed to be selective and that I would make my decision at some point.

But it did say I would have confidence that I had chosen right when I saw I was following in the footsteps of the Savior, becoming like him, ministering to others in their need. It also mentions being an influence for good and leadership opportunities.

I gotta admit, that doesn't sound much like my engineering job.

(I've tried to rationalize that carpentry and engineering are similar career paths, but I know in my heart that's not what the revelation means.)

There is no ministering to others at my current place of employment. We barely exchange glances. I mostly sit in silence in my private office. Perhaps I'd minister when I become a manager? Eh, that's a weak attempt at fitting a square peg into a round hole, isn't it?

So...teaching? Probably math or physics at a high school level? Is that grass any greener?

Measuring Temperature and Comfort Levels

Humans are terrible thermometers.

You see, the way thermometers (things that measure temperature) work is they sit in something or are surrounded by something at the temperature they want to measure. As they sit, they exchange heat through conduction or convection or radiation. After some time, the thermometer is in thermal equilibrium with its surroundings. It becomes the same temperature as the surroundings!

People don't do that. In fact, they hate that. They die when they do that.

We're finicky. We want to be kept at precisely 98.6 degrees Fahrenheit on the inside. But we don't like 98.6 degree weather. Have you ever wondered why?

We are heat sources. Every cell in our bodies consumes sugar and oxygen and gives a little burst of warmth when it combusts. And that warmth builds up. We keep exactly enough to maintain our core temp (98.6 degrees) and dump the rest into the outside world. Heat only travels from hot areas to cold areas, so we actually prefer a cooler environment (say, 70 degrees).

Heat sources make terrible thermometers. Instead of settling on a constant temperature (like most things), we like to settle on heat rates: the amount of heat energy we produce.

The FDA has recommended food intake of about 2,000 kilocalories per day for an average human. That converts to about 100 watts (or 100 Joules per second). Granted, not all of that is converted into heat, but it's a good round number (and I eat way more than 2,000 kcal per day), so let's go with it.

This means that we feel most comfortable not in a particular temperature range, but in a particular heat transfer rate range. Around 100 watts.

What's the difference? Heat transfer rates depend on temperature difference (from your body to the air outside), but that's not all. Heat transfer rates also depend on wind speed, humidity, thermal conductivity of insulation (everything from parkas to blubber), insulation thickness, and surface area. If you're in view of something very hot (like the sun or a fire) or very cold (like a cloudless night sky), the color and finish of your surface will play a big role as well.

Thinking about your optimal heat transfer rate instead of your optimal outside temperature may help you make better comfort decisions.

Here are some examples:

1. You know those terrible gloves that don't work? They may actually be increasing your surface area enough to counteract the minimal insulation they provide.
2. I remember discovering as a child that blankets don't make "things" warm. They only work on people and animals (well, really only mammals and birds), because we are heat sources. Insulation just slows down heat flow, it doesn't generate any heat.
3. Turn on your fan, even if it is blowing 85 degree air at you. Higher air speed increases the heat transfer rate.

The Golden Age

Think of the place where you were happiest as a child. Where is it?

I thought of several:

Grandma and Grandpa Spencer's condominium swimming pool. I loved swimming. To be suspended in microgravity, with freedom to move in any direction. To play and move. And then, wrapped in a towel, with wet hair and burning eyes, to eat fluffy chocolate chip cookies in the cool air of the condo.

Our orchard. Rows of apple trees, seemingly endless to young eyes. I was privileged and could wander; my neighbors contained themselves in rigid boxes made of fences. I helped: pile up pruned sticks in the spring for a bonfire and hotdogs; scatter white fertilizer pellets near the trunks; plow furrows with the tractor; harvest sweet apples, peaches, plums, cherries.

Our wet lawn. Inch-deep water from irrigation. Bare feet, bare chest, sneaking pea-pods and black-caps from the gardens. Chasing chickens for sport.

Our rectangular trampoline. It had more bounce than any other I knew. On hot days, I would wait impatiently for the sun to fall behind the house and I'd drag the tramp almost to the bricks; with a little shade I could spend all evening there, especially with the smell of fresh-cut grass or a family reunion barbecue.

The Fort. It was a collaboration. And a creation. Something that would not have existed but for our imaginations and our proactivity. Kris led, I worshiped. We salvaged scraps from Uncle Paul's housing construction (and one local eatery); we taught ourselves carpentry; we furnished and adorned it; we lived there as a refuge from rules and parents; we invented; we pioneered: we even farmed. It was our frontier, our manifest destiny. My Zion.

General Conference Review

You know how you can always listen to General Conference and if you make it a matter of prayer and pay close attention to all the talks and take good notes, you'll have revealed the thing the Lord wants you to take away from it?

You know how sometimes it may just be a subtle hint in one of the talks or it may be totally unrelated to any talk, but it's just the quiet whispering of the Holy Spirit that only came because you made listening to the Prophet a high priority?

Well, I got one.

It was a simple message.

You might have missed the references.

I think the Lord wants me to...

Open Source in Meatspace

I have been thinking about printer designs lately.

Inkjet, laser, whatever. The companies that make them (HP, Kodak, Canon, Lexmark, Brother) rely on the following basic business model:

• Sell customers the printer, earn $60-$300
• Sell customers proprietary ink cartridge refills, earn $25 every other month
• Printer breaks down after 2-3 years, repeat

In short, they are happy to make money on the initial investment, but the real cash cow is the returning business for the ink. It beats the old business model of selling defective products that need more frequent replacement, but the ink business is still an artificially-induced demand market. Ink cartridges could be standardized and ink could cost a whole lot less money, but that is how these companies stay afloat. It's either this or pay ten times more up front for the printer.

It got me thinking.

The expertise for a more intelligent design of printers is out there. Engineers and manufacturers already have interest in such designs. In a parallel world, the software industry has found an incredible resource in the open-source community for putting together large coding projects that would be altogether too big for a single tinkerer (which is what they mostly are -- software developers with real jobs and tinkering on open source projects on the side). Their capacity for creation seems almost limitless for them, except for the limit of the computer screen.

The advantage that software developers have is that it really just comes down to expertise. That's what you pay for in a computer program: the smarts of the people creating it.

In manufacturing a meatspace product, however, on top of expertise you have:

• Raw materials
• Fabrication facilities (machines that cut, mold, weld, form, etc.)
• Quality assurance, safety, insurance (meatspace products have more of a tendency to injure than raw code does)
• Distribution (I long for the days of replicating and emailing pieces of plastic and steel)

I am rather confident that engineers working together en masse in their spare time could eventually design a much better printer than we now have. It would last longer, require less ink maintenance and would be entirely open-source for iterations and improvements from other tinkerers.

It's just the manufacturing that's got me puzzled.

Any ideas?

Hi, I'm Cassandra I am an Artist, a Wife, a Mother and I'm a Mormon

Dan Barney was my AP art teacher at Timpview. He is great. Here is his wife Cassandra, who is also an artist and a Mormon!

Too much to absorb

My internet attention span is too short to write high-quality blog posts. I blame Google Reader's "Recommended items" button.