The Inevitable Liberator

At first glance, it seems an unlikely catalyst for profound liberation and utility. However, I need only think back to the heady days when I turned 14 and got a Honda Spree.

In my case, the prime usages were to add a whole new (motorized) dimension to games of tag with my friends or to let me ride by girls' houses in relative class and style.

According to articles in the New York Times printed just a couple days apart, motorbikes are having a similarly stupendous effect on the lives of Iraqis and Laotian villagers.

Worst Ever?

Here'a a devestating and depressing commentary on President Bush's "stewardship" of the American economy from the December issue of Vanity Fair.

So we're in a fine mess.

I take a little solace in the fact that perhaps President Hoover (from nearby West Branch) can rest easier.

Another Kind of Black Gold

On December 17, 2006 the S&P 500 closed at 1,422.48. Yesterday, it closed at 1,445.90 for a one year gain of 1.65%.

Unfortunately, the inflation rate over that period was measured at higher rates in each and every month of the timeframe with the highest rates of 3.54% and 4.31% coming in October and November (the last two months for which data is available.)

Investors should have looked for something racier. Something with more growth potential. Something like Iowa farm land. From the Des Moines Register:

Iowa farmland increased 22 percent in the last year, the highest increase in 21 years, according to a survey by Iowa State University Extension.

Five counties now boast an average "good" agricultural land value of over $5,000 per acre.

Isn't this bad?

From the New York Times:

The increase in incomes of the top 1 percent of Americans from 2003 to 2005 exceeded the total income of the poorest 20 percent of Americans, data in a new report by the Congressional Budget Office shows.

So... The INCREASE from the top 1 is bigger than the TOTAL of the bottom 20... And this from a two-year period?!

I'm thinking this is one of those things that is bad news for everybody. It's definately less bad for the top 1 percent! I'll grant you that. But what I'm suggesting is that a concentration of wealth at levels commensurate to the Roman Empire is not sustainable. The rich have made the "mistake" of becoming too weathly.

Perhaps, unlike the example of the Roman Empire, the uber-wealthly will be able to safely extract their wealth and themselves before everything falls apart. We'll see.

It seems to me that Capitalists are too busy making money to be bothered with maintaining faith in the capitalist system. That could be a problem.

All RPM are not created equal

The riddle from the previous post is solved. My college roommate responded via e-mail. The remainder of the post is his words:

I plotted quite similar data points for the Omni about fifteen years ago. (In fact, I thought you were the data recorder as I called out the numbers. This was on I-80 on the way to Iowa City.) I tried to eliminate all of the obvious sources of error: I did it all in the same gear--though it was an automatic, I took my first data point after the shift to the highest gear. I did my best to maintain an even speed. I attempted to ensure that I was in "clean" air. And yet, I still got the sort of curve you describe.

I have since accepted--I suspected it at the time, but I liked the curve so much I didn't want to accept reality--that there was a flaw in my fundamental assumption: That rpm are a good indicator of fuel consumption. While there is obviously a close relationship, it is apparently sufficiently inaccurate to completely invalidate experiments like ours. The issue is that the gas pedal was down farther for the higher speeds, and thus the throttle valve was wider open. The engine was enjoying more fuel vapor per revolution. From Howstuffworks:

When you step on the gas pedal, the throttle valve opens up more, letting in more air. The engine control unit (ECU, the computer that controls all of the electronic components on your engine) "sees" the throttle valve open and increases the fuel rate in anticipation of more air entering the engine. It is important to increase the fuel rate as soon as the throttle valve opens; otherwise, when the gas pedal is first pressed, there may be a hesitation as some air reaches the cylinders without enough fuel in it. Sensors monitor the mass of air entering the engine, as well as the amount of oxygen in the exhaust. The ECU uses this information to fine-tune the fuel delivery so that the air-to-fuel ratio is just right.

Apparently the increase in the amount of fuel supplied per revolution more than offsets the savings in rpm. To actually test that you'd have to have some way of reading the data from your ECU. I suspect that is precisely what the cars are doing that give you a "real-time" mpg readout.

Does not compute

I'm in the process of buying a new car (more on this later) and I'm keen to see how my gas milage will improve. I think the most accurate comparison, of course, will come by recording milage and gas consumption readings over time for similar driving patterns. I'm all set there because I already maintain a milage spreadsheet.

I've purchased 582.495 gallons of fuel this year at a total cost of $1,615.68.

Yes, I'm a dork.

But this morning on my way to work, I had the impulse for a different method of comparison. Although any differences in engine displacement would complicate things, I thought I would record a few RPM / Speed ratios (all in fifth gear) for the Beetle and then see how they compared to the new car. The results were troubling.

RPM	Speed	RPM/MPH
2500	55	45.45
3000	68	44.12
3500	79	44.30

See the problem? My awkward (but I believe useful) metric of Revolutions per Minute per Mile per Hour shows that it's more fuel efficient to drive at 79 mph than at 55. How could this be? I thought President Carter wanted us to drive 55 because it would save energy?

When I was very young, I remember assuming that the body shape of an auto was the dominant performance factor. In my personal experience, a more aerodynamic Matchbox car outperformed a less aerodynamic Matchbox car in all but the most improbable circumstances, i.e., the race was interrupted by a cat or a well aimed rubber band. In the abscence of any contravening data, I assumed the aero-primacy extended to actual automobiles.

So I managed to completely overlook engines. In later years, with the benefits of "real life" driving experience, I started thinking the key was gear ratios. If you've got the perfect gear ratio, you've got the perfect performance. Right?

Well... Kinda, but my six year old self was actually on to something.

From the Wikipedia article on Auto Fuel Economy:

The power to overcome air resistance increases roughly with the cube of the speed. Thus, above about 30 mph (48 km/h), wind resistance becomes a dominant limiting factor. By driving at 45 rather than 65 mph (72 rather than 105 km/h), the power to overcome wind resistance is about one-third, and much greater fuel economy can be achieved. Increasing speed to 90 mph (145 km/h) increases the power requirement by 2.6 times, and drastically decreases fuel economy. In practice, rather than doubling or halving the fuel economy, the difference is actually closer to 40-50%, since rolling resistance, which is broadly proportional to speed, is also a factor.

So OK, gearing is important and aerodynamics too. But why, for the Beetle, are these readings not showing a significant milage penalty for higher speeds? What am I missing here?

Could it be as simple as bad data points?

It's not like I took the 2500 RPM reading driving uphill pulling a trailer and the 3500 RPM reading going downhill in a hurricane.

Note: If any interesed members of local law enforcement agencies are reading this, note that the 79 mph reading was taken on a closed course rather than on public roadways.

What didn't he do?

I learned today that Benjamin Franklin gave the Gulf Stream its name.

Get outta Kar-Tomb

Usually, "teddy" crisis involve conservative English cabinet secretaries so the recent events in Sudan have, if nothing else, provided a change of pace.

I have two primary reactions to the curious case of Gillian Gibbons:

1.) I'm astonished that anyone could face 40 lashes and 6 months in prison for giving any name to any thing. So much for "Sticks and stones..."

2.) Why aren't Mohamed El Baradei's parents in trouble? Is the rule that you can name people after Mohammed, but not anything else?

I find it strange that it would be acceptable for, say, a disreputeable cab driver in Lahore to carry the name, but a teddy bear named with earnest intentions by school children causes an international crisis.

Addendum: After the original post, I saw this topic come up in Slate.com's Explainer series. When Can Muslims Use the Name Mohammed?