Gas station without pumps

2016 August 1

Yet another weight progress report

Filed under: Uncategorized — gasstationwithoutpumps @ 12:41
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This post is yet another weight progress report, continuing the previous one. I’ve lost track of the number—somewhere around 18 reports, since they have been roughly monthly since I started in January 2015.

Here is the detailed look for the past year.  As you can see, July has been a bad month, with no days in my target weight range.

Here is the detailed look for the past year. As you can see, July has been a bad month, with no days in my target weight range.

On a longer term basis, it is clear that I'm still doing much better than before I started the diet, but the recent trend to higher weight is not encouraging.

On a longer term basis, it is clear that I’m still doing much better than before I started the diet, but the recent trend to higher weight is not encouraging.

Exercise has been very low this month, with only 2.6 miles/day of bicycling. I don’t have exercise built into my daily routine, and I find it very difficult to exercise just for its own sake. I need to find a way to build more exercise into my routine when I’m not commuting—for the summer, for my fall sabbatical, and (longer-term) for when I retire.

I’d like to lose 5 pounds to get back to the middle of my target range, and that will probably take the rest of the summer, if it happens at all. July has not been an encouraging month weight-wise.

2016 July 22

Modeling bicycle balance—a disappointing Nature article

Filed under: Uncategorized — gasstationwithoutpumps @ 17:38
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The bicycle problem that nearly broke mathematics in Nature News & Comment is a badly titled (click-bait) article that talks about one person who contributed to the development of  the differential equations that accurately describe bicycle balancing (which has been incorrectly or incompletely described many times in the physics and engineering literature).

The one-line summary of the article is pretty accurate:

Jim Papadopoulos has spent a lifetime pondering the maths of bikes in motion. Now his work has found fresh momentum.

There is nothing in the article giving any indication that the equations Papadopoulos derived provided any stress to mathematics.  The problem, as in many physics problems, is all in deciding what needs to be included in the model to get the best compromise between the tractability of the model and its accuracy.  So far as I can tell from the vague descriptions in the article, the equations themselves are pretty much standard PDEs.

Unfortunately, the article does not give the equations themselves, so this article is particularly disappointing.  It is People article, not a science article.

The article did give one prediction from the equations that showed their worth: it is possible to design a rideable bike with no gyroscopic balancing and negative trail, which would be inherently unstable in previous, simpler models. The trick is to move the center of gravity far enough forward to be ahead of the steering axis. Supposedly, such a bike has been built [Kooijman, J. D., G. Meijaard, J. P., Papadopoulos, J. M., Ruina, A., Schwab, A. L. A Bicycle Can Be Self-Stable Without Gyroscopic or Caster Effects Science 3(32), 339–342 (2011) http://dx.doi.org/10.1126/science.1201959], but that article is hidden behind the Science paywall, so you’ll need to go to a university library to access it.

The supplementary material for the Science article is where the equations are presented and explained.

2016 July 14

Quax

Filed under: Uncategorized — gasstationwithoutpumps @ 00:02
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I just ran across a new word: “quax”.

According to Wikipedia’s entry:

Dick Quax tweeted[6] in January 2015 about his disbelief that anyone in the Western world would go shopping by means of a train or bicycle (or by bus, ferry, etc., presumably). Twitter users responded by creating the #quaxing hashtag, defined below.[7]

The Public Address website voted quaxing as its word of the year 2015, followed by Red Peak and Twitterati.[8]
Quax, [verb; past: quaxed, present: quaxing] — to shop, in the western world, by means of walking, cycling or public transit. #quaxing
— Non-motorist (@ByTheMotorway)
26 April 2015[9]

I’ve been quaxing for decades now and expect to do so for decades more.

2016 July 4

Bike Parking in Montreal

Filed under: Uncategorized — gasstationwithoutpumps @ 18:00
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I have a collection of photographs of different types of bike parking, and I added two more types in my June 2016 trip to Montreal:

There are parking posts like this one all over Montreal, numbering the parking spaces for payment, but only a few of them have the extra ring for locking bicycles to the post.

There are parking posts like this one all over Montreal, numbering the parking spaces for payment, but only a few of them have the extra ring for locking bicycles to the post.

This 8-bike rack was spotted on the McGill college campus, in front of their natural history museum. It makes a nice sculptural statement, and is moderately compact, but looks a little difficult to use with tandems, recumbents, children's bikes, and others that don't fit the rather narrow idea of what the dimensions of an adult bike are.

This 8-bike rack was spotted on the McGill college campus, in front of their natural history museum. It makes a nice sculptural statement, and is moderately compact, but looks a little difficult to use with tandems, recumbents, children’s bikes, and others that don’t fit the rather narrow idea of what the dimensions of an adult bike are.

2016 June 30

Seventeenth weight progress report

Filed under: Uncategorized — gasstationwithoutpumps @ 08:58
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This post is yet another weight progress report, continuing the previous one. I skipped posting last month, because I was busy and my weight was up—I had hoped to bring it back down during June so I could report good news, but a trip to Montreal and a trip to San Francisco, with the concomitant loss of diet control resulted in my weight going up even more in June:

My weight has been creeping up, mainly as sudden upward spikes that take a while to recover from.

My weight has been creeping up, mainly as sudden upward spikes that take a while to recover from.

The detailed view of the last year shows a fair amount of scatter over an underlying gain of 2.81lbs/year (1.275kg/year). May had only 5 days above my self-imposed target range, but June had only 4 days within the range!

The detailed view of the last year shows a fair amount of scatter over an underlying gain of 2.81lbs/year (1.275kg/year). May had only 5 days above my self-imposed target range, but June had only 4 days within the range!

Exercise has been very low this month, with only 2.59 miles/day of bicycling (though I did more walking than usual, particularly on the Montreal and San Francisco trips). Because I’m not commuting up to work daily over the summer, I don’t have exercise built into my daily routine, and I find it very difficult to exercise just for its own sake.

It has also been difficult to be diligent about my raw-fruit-and-vegetable diet, both at home and when traveling. There are lots of snacks and leftovers in the house, because my son is home from college, and he needs lots of calories—he’s almost as skinny as I was at his age, though he doesn’t eat as much as I did at that age. He needs the calories, and I don’t, but I find it difficult to resist snacks when they are right there, even when I’m not hungry.

I’d like to lose 7 pounds to get back to the middle of my target range, and that will probably take the rest of the summer, even if I manage somehow to be as diligent about my diet as I was for the first few months of it. I don’t know that I have the willpower to be that diligent over the summer.

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