July 06, 2014


Renee is taking MTH 251 (differential calculus) this fall. Herein some notes on resources.


Online Resources

Posted by dpwakefield at 04:56 PM | Comments (0)


Renee is taking MTH 251 (differential calculus) this fall. Herein some notes on resources.


Online Resources

Posted by dpwakefield at 04:56 PM | Comments (0)

October 03, 2009


University of Nottingham hosts a site called Sixty Symbols. I've been meaning to begin viewing them, and will note them here. For your viewing pleasure, here's the one for a solar Eclipse.

P.S. - I should note that in fact this was not the first video I watched. While the solar eclipse video is basically a fun diary-of-an-eclipse, it doesn't have much beyond a couple of neat video shots of the eclipse to recommend it.

On the other hand, the video on the fine structure constant is all hard science and wonder, in one capsule interview with a real live physicist, who clearly digs the magic of physical constants.

Posted by dpwakefield at 08:50 PM | Comments (0)

September 17, 2009


I've tried in the past to read some of Feynman's autobiographical books, and gave it up each time as too annoying. I acknowledge that he was brilliant, but he knew it, and it showed, if you know what I mean. Annoying.

So today Kottke pointed to an interview with Murray Gell-Mann, wherein he answers a question about his relationship with Feynman:

Feynman was pretty good, although not as good as he thought he was. He was too self-absorbed and spent a huge amount of energy generating anecdotes about himself.

Spot on, as far as I can tell.

Posted by dpwakefield at 09:26 PM | Comments (0)

March 26, 2009


I was talking with Renee the other day about homemade bread, and a recipe that I used to make nearly every week when Jean and I were 'poor'. It was a hybrid of a recipe I got out of Laurel's Bread Book. Counting rise times, kneading, baking and cooling, it was an all-day affair, but resulted in two loaves of whole-wheat bread that had a coarse crumb and terrific taste. Two slices with a bit of tomato made a meal.

Turning on that subject, I mentioned that some of the heavier hand-crafted beers of today resembled colonial beers which were rich enough in calories that a pint might as well be a meal (don't know how many vitamins you can count on from a dark beer, though). Then of course I mentioned the salutory effect of alcohol on limiting water-borne diseases. I mentioned how the classical Greeks mixed water with wine, which might have reduced the antibacterial properties somewhat, but at least led to a less inebriated populace.

So how does this feed into the quote of the day? Whilst laid up with a bad back, I took advantage of Amazon's introduction of Kindle for iPod to download a couple of books for my iPod Touch. One of them was The Ghost Map, which I'd partially read from the library when it came out, but never finished. So I'm reading it now, and what should I see, but:

The search for unpolluted drinking water is as old as civilization itself. As soon as there were mass human settlements, waterborne diseases like dysentery became a crucial population bottleneck. For much of human history, the solution to this chronic public-health issue was not purifying the water supply. The solution was to drink alcohol. In a community lacking pure-water supplies, the closest thing to "pure" fluid was alcohol. Whatever health risks were posed by beer (and later wine) in the early days of agrarian settlements were more than offset by alcohol's antibacterial properties.

And the money quote:

Dying of cirrhosis of the liver in your forties was better than dying of dysentery in your twenties.

He goes on to discuss the theory that selection pressures actually favored descendents who could "hold their liquor", or beer, actually, as those who could not, either died of alcohol poisoning or dysentery before bearing children. The majority of the human race, therefore, now has genes which produce enzymes called alcohol dehydrogenases, allowing the ingestion of 'large' quantities of alcohol.


I now have an indictment of some aspect of the Kindle toolchain, I don't know where. In reading the book, I remember that Johnson earlier spoke about how the adoption of tea drinking in England also contributed to the health of Londoners:

Brewed tea possesses several antibacterial properties that help ward off waterborne diseases: the tannic acid released in the steeping process kills off those bacteria that haven't already perished during the boiling of the water. The explosion of tea drinking during the late 1700s was, from the bacteria's point of view, a microbial holocaust. Physicians observed a dramatic drop in dysentery and child mortality during the period.

However, in trying to locate this passage, I ran into a roadblock (I eventually used Amazon's own "Search Inside This Book" facility). On the iPod Touch, at least, while the index for the book is included, and there is an entry, bacteria, tea and, the index entry does not link back to the relevant text! Really??? I don't know if this is a limitation of the Kindle conversion of this book, a limitation of the Kindle conversion for iPods, or what, but it renders the index a cruel joke. Now if I wanted to drop big bucks on the actual Kindle e-book reader, I could use search:

Kindle makes it easy to search across your library. To use the Search feature, simply type in a word or phrase you're looking for, and Kindle will find every instance across your Kindle library.

But I don't intend to drop that kind of money, and I actually like reading on the much more portable iPod. The upcoming summer release of iPhone OS 3.0 holds out some promise:

Search capabilities will be expanded, allowing customers to search within Mail, iPod and Notes or search across all key apps by typing a key word or phrase into the new Spotlight search, conveniently accessed from the Home screen.

The only question here is, what are "key apps"? I sure hope I'll be able to use Spotlight to search my Kindle books, but I'm skeptical that that will happen...

And of Course, Illustrations...

Don't get a book if the illustrations are critical to understanding the text. They might be large enough on a Kindle, but not on the compact screen of an iPod Touch. Fortunately, though both the books I bought have a small set of illustrations, they are not critical to the understanding of the books.

Posted by dpwakefield at 09:25 PM | Comments (0)

February 20, 2008

Werewolves of Portland

Yes, we saw the lunar eclipse tonight, Renee and I. Got there a few minutes before the last bright wedge disappeared behind the umbra, and then walked around the neighborhood for a while looking for darker blocks.

Unfortunately, I don't possess camera equipment sensitive enough to capture this in city lights, so memories will have to do.

Posted by dpwakefield at 07:14 PM | Comments (0)

July 11, 2007


I can't remember with certainty when we last experienced a notable earthquake here in Tualatin, but I do remember that I was half-asleep in bed. This time, I was noodling on the computer. It was a 2.9, maybe ten miles away and 16 miles down. There was no missing it, but not enough force to knock things over.

So long as that's the strongest I experience, cool!

The shakiest quake I ever experienced was in Cuyahoga Falls, Ohio. I was in our apartment, and could see the floor lamp's shade swinging left and right as I felt the entire building sway. That one had me worried for awhile...


Ooh! Overnight it got upgraded. The automatic machinery gave it a 2.9, but it's now ranked a 3.3! Cool!

Posted by dpwakefield at 09:06 PM | Comments (0)

August 10, 2006

Fear of Flying

...an American’s chance of being killed in one nonstop airline flight is about one in 13 million (even taking the September 11 crashes into account). To reach that same level of risk when driving on America’s safest roads — rural interstate highways — one would have to travel a mere 11.2 miles.

Steve Berliner Johnson

Posted by dpwakefield at 09:23 PM | Comments (0)

July 25, 2006

Butterflies Are Free

When we got home, we discovered that the butterflies had emerged. I'm glad I insisted that we leave some orange wedges in the canopy. We waited until it cooled off a little in the evening, then Renee and I took the canopy out to the back balcony. One of the butterflies fled immediately when we opened the canopy. A couple more escaped as I was adding a fresh wedge of orange. There was one straggler climbing around, looking a bit weak. I checked again this evening and it's gone. So that's it. Renee is a naturalist!

Posted by dpwakefield at 09:42 PM | Comments (0)

February 12, 2004

Oliver Sacks

Another link for someone else, this time my wife:

Oliver Sacks has a web site. Too bad it has the annoying trait of resizing your web browser...

Posted by dpwakefield at 09:21 PM

December 11, 2003

Uncanny Valley

If like me you were unfamiliar with the phrase "uncanny valley", you can get a great introduction by reading this paper (pdf document) by Dave Bryant:

Stated simply, the idea is that if one were to plot emotional response against similarity to human appearance and movement, the curve is not a sure, steady upward trend. Instead, there is a peak shortly before one reaches a completely human "look" ... but then a deep chasm plunges below neutrality into a strong negative response before rebounding to a second peak where resemblance to humanity is complete.

If you get creeped out by zombie movies, or see a face in the fog on your bathroom mirror and the hairs on the back of your neck stand up, Dr. Masahiro Mori would explain it this way: these are things which seem very human, but off-kilter, uncanny in a way the brain can't explain. Dr. Mori was a roboticist, interested in what made humanoid robots more effective. As it turns out, making them too human creeps people out, because they end up in the 'uncanny valley'.

The conclusion drawn by the good doctor is that designers of robots or prosthetics should not strive overly hard to duplicate human appearance, lest some seemingly minor flaw drop the hapless android or cyborg into the uncanny valley -- a fate to be dreaded by all concerned.

Posted by dpwakefield at 09:03 PM