Michael A. Covington    Michael A. Covington, Ph.D.
Senior Research Scientist
Adjunct Professor of Computer Science
Associate Director
Institute for Artificial Intelligence
The University of Georgia

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What a leap second sounds like
How to tackle a big project
Windows: black screen, mouse cursor
2 important settings for Windows Vista and 7
Edmund Scientific Company Catalog 645
Adding Vista to an XP roaming network
Must we unplug our unused phone chargers?

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IC 1318 B (Butterfly Nebula)
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A safety feature that can backfire

Any large electric power tool is likely to have a magnetic switch, which means the "start" button energizes a relay which then uses its own output to keep itself energized and keep the motor switched on. The result is that if there is a momentary power failure (or if the thermal overload switch opens momentarily), the motor will stop and not restart.

That is a valuable safety feature in power failures, and even more importantly, you cetainly would not want the motor to get into an oscillating loop with its own thermal cutout, so that it heats up, stops, cools down, and restarts, over and over. So far so good.

But the contacts in that relay are only a millimeter apart, or so, and anything that shakes the relay can make the contacts come together for a moment. Then the relay holds itself in and the motor starts up. Read here about the table saw that started when a board fell on it, and similar adventures.

This is the kind of thing engineers should think about.

I'm very busy and may be late getting the February page started. Don't panic if it's not there for a few days.

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Farewell to Z
Zim's Bagel Bakery, 1993-2009

I'm posting this early to give people a chance to visit Zim's Bagel Bakery (Beechwood Shopping Center, Athens, Georgia) one last time. Friday, Jan. 30, will be its last day of operation. Newspaper story here.

Zim's opened in 1993, and for a few years, I avoided it, figuring all I'd find there was bagels. Then Melody introduced me to the lunch and dinner buffet, and as a family, we ate there regularly. There was a constantly changing variety of food, strong on salads; the surroundings were unique, with bright colors, faux clouds hanging from the ceiling, and inscriptions on the tables and chairs; and the odds of running into long-lost friends were very good.

About those inscriptions... Painted on the tables and chairs were quotes from everything from the New Testament to Alice in Wonderland, as well as lots of light verse and whimsy. "So this is this, and that is that: be careful how you address a cat!"

Zim's will be missed.

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Must we unplug our unused cell-phone chargers?

The Department of Energy is airing public service ads on TV telling us to unplug cell-phone chargers when we're not using them, to save energy.

Is this good advice? No, unless they know something I don't.

Hear me out.

Transformers don't waste a lot of energy. Not much more goes in than comes out. Not much at all goes in when nothing is coming out. This is especially true of modern switching regulators, which are commonly used to charge cell phones.

The energy that does get wasted is nearly all turned into heat and can be measured as such.

So, just now, I went over to a cell-phone charger that had been idle for half a day, but still plugged in, and felt it to see if it was warm. No. In fact, a non-contact thermometer told me it was within 1 degree C of surrounding objects.

From experience I've learned that a dissipation of 1 watt will make a small object quite warm (in fact, will make a small electronic component too hot to touch). So I'm guessing the energy wasted by the charger is no more than 1/4 watt, and possibly much less.

Suppose it's 1/4 watt. Then it takes 4000 hours to burn 1 kWh of electricity, which costs about a dime.

That's right — if you unplug it when it's not used, you can probably save a dime in six months.

But there are other costs. Repeatedly unplugging the charger and plugging it in again will put some wear and tear on the plug. I've seen a prong actually come out of a cell-phone charger. I have another one that apparenly has a broken connection to one of the prongs internally. So in your quest to save a dime, you're quite likely to wear out a $30 charger prematurely.

Then there's the value of your time and effort. To save that ten cents, you probably will have to unplug the charger something like 50 times, taking about 10 seconds each time. That's about ten minutes of work. Isn't your time worth more than 60 cents per hour?

And here's the clincher. You might not want to save that energy. In the winter, if it's turned into heat, then it helps heat your house, and otherwise you'd have to buy the same amount of energy some other way.

So why unplug your cell-phone chargers? To show that you are self-righteously Saving The Earth, and that you're willing to waste almost anything else, as long as you can claim you're saving a paltry amount of precious electricity.

There are those who would say that the saved electricity is worth more than the ten cents that it costs. To that I reply: Then the price is wrong! Either electricity goes for a fair price on the open market, or something is distorting the price. If the latter, please tell us what.


A bit of shopping this evening confirmed our earlier impression: Stores are neat and clean, desirable merchandise is no longer on clearance, and some prices are sharply higher (like Krylon spray paint, $6 per can at a craft store, but still $3 at Wal-Mart).

I continue to predict a burst of inflation, arriving unexpectedly as soon as the downturn ends.

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Very short notes

I know it's the end of the month, but you don't actually have to send me e-mail today, although numerous people have decided to do so. (I must have handled 200 messages actually needing replies.) It's not a special occasion; it's just the fourth-week-of-the-new-year oops-we'd-better-start-doing-some-work frenzy.

Another shifty woodworking term: I just learned that deal in the British sense of "common pine or fir lumber" is unrelated to our familiar word deal as in "let's make a deal." It's actually a German word that came over during the Middle Ages.

My father, an American veteran of RAF Molesworth, may be in this movie. One day I'll get around to watching it and looking for him.

Canon's newest product: Babies. That's right — young married employees of Canon Japan are being urged to start families. Japan is experiencing a severe population decline, and that means an age hump — if you have a shortage of children, you soon have a lot of old people with no one to take care of them. Back in the 1970s we were all told the world was suffering a Malthusian "population boom" which would cause mass starvation within our lifetimes. That was a complete mistake, and we now realize that if developed nations depopulate themselves, the whole world will become poorer.

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Shifting terminology

While helping Cathy with a woodworking project, I started reading some woodworking web sites, and noticed a change in terminology: what used to be the splitter in a table saw is now called the riving knife (rhymes with striving). Hmmm...

I've watched the terms jig saw and scroll saw swap meanings since the 1960s, too. Why is woodworking terminology so volatile?

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Short notes

Economy shifting gears again? Further to yesterday's note, I see some signs of economic recovery, or at least readjustment. In the stores, the post-Christmas clearances seem to be over; things are neat and orderly now; and some prices are sharply higher. Maybe the real effect of the stimulus package will be a burst of inflation, and maybe that's what people and businesses actually want.

Smart table saw: Have you seen the Sawstop? It's a table saw that detects, electrically, when the blade comes in contact with the human body (or, in demonstrations, a hot dog that is in contact with the operator's hand) and instantly stops and retracts the blade, quickly enough that it makes only a small scrape on the skin (or hot dog). This is exactly the kind of thing I like to see people inventing.

There are just three disadvantages: (1) there isn't a SawStop small enough or low-priced enough for small shops, such as mine; (2) the safety mechanism ruins the blade (by ramming an aluminum block into it) when it triggers; and (3) people seem to be taking chances with it, even deliberately running their finger into the blade to see it stop, which is a very bad idea because you can't be 100% certain that it will trigger when it should.

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Recession? What recession?

Yesterday (Saturday, Jan. 24), Melody and I tried to run some errands, and two of Athens' shopping centers (Alps and Beechwood) were positively teeming with cars and people. We couldn't park at Alps at all. Beechwood was gridlocked. Zim's (our favorite restaurant) was almost full — we had almost never seen it more than half full until then. Later, we went to Dos Palmas for dinner and found it, also, almost full.

Did the recession end, or was it just the warm weather? Are people out spending money or just roaming around in stores?

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Adding Vista and Windows 7 to an XP roaming network

Updated Jan. 27, 28.

At the Institute, we're starting to add Vista machines to a Windows XP roaming user network and allow users to roam back and forth between PCs running both operating systems. I have not finished implementing this, but here are the key ideas:

  • Vista and XP have separate profiles for each user, named (for instance) jones and jones.V2.
  • Users' profiles and My Documents folders are redirected to the disks on the server where they are stored. In XP, this is done via attributes of the accounts; in Vista, via Group Policy.
  • It follows that you must make some Group Policy settings that are new to Vista and aren't editable on the Windows 2003 server. This is done by (a) logging in to a Vista machine with a domain administrator account; (b) downloading and installing the remote server administration tools (RSAT); (c) turning RSAT on as a Windows feature; (d) opening GPMC.MSC (Group Policy Management Console).
  • Group Policy objects don't have any effect unless they are linked from the domain. This is in GPMC.MSC and fairly obvious once it's pointed out. GPMC.MSC also includes a tool to find out what the actual policies in effect are, and where they came from.
  • The settings to make are approximately described in this slightly out-of-date document, but in matters of detail, we are probably not going to do exactly what they say. The key ideas are: (1) redirect Desktop and My Documents to the same places as in XP; (2) make Music, Videos, etc., "follow the Documents folder" rather than residing in their new-style Vista locations; (3) make sure all of these settings apply only to Vista, not XP.
  • If the permissions on the redirect folders aren't right, the redirection won't happen and you'll get Event 502. For the details of the required permissions, see Microsoft KB274443.

We also confirmed briefly that, with no further changes, this setup also enables users to roam to Windows 7 Beta.

Please don't ask me any more questions about this — I don't have answers. But based on what I've sketched, you should be able to search for more information.

Very soon I'll know whether the requirements of Windows 7 are the same as Vista. I think they will be. I know Windows 2000 is the same as XP (that is, when we moved the users from 2000 to XP we did not have to make any change to the roaming user profile system). Apparently, Windows Server 2003 and 2008 also side with XP as regards the type of roaming profile used.

Note: We eventually opted not to do this; Folder Redirection introduces as many complexities as it solves. See notes in February.

Two short notes

Obama has forbidden the use of torture in interrogations (good) and permitted the use of taxpayer money to fund abortions through international organizations (bad). Regarding abortion I'll say just three things.
   (1) The issue is not whether you believe in women's rights, it's whether you believe that a fetus (or a premature baby) is a human being (fetuses and premature babies are the same thing except for location). For the same reason, slavery was not a property-rights issue.
   (2) Americans are deeply divided about abortion and I wish the government had more respect for our consciences. We aren't required to fight in the army if our conscience forbids it; why require us to pay for abortions?
   (3) It's a pity that opposition to abortion has become identified with right-wing positions that often put a lower value on human life in other situations (capital punishment, war). The people who say this connection is illogical are right.

On a lighter note, it appears that when I began to take an interest in educating people about personal finance, I was performing a valuable public service which, according to Robert Shiller, ought to be subsidized. Maybe so. Or maybe they should teach personal finance in high school, along with civics, rather than just prerequisites for college courses. It's easy for educational systems to get caught in a trap where every course is nothing but the preparation for some other course.

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Advice to state universities

"There are a number of steps we can take to control costs and improve access to higher education. States can limit annual tuition increases at public universities. ... And students can insist that their institutions focus their fund-raising efforts more on improving the quality of the instruction than on building new football stadiums."

— Barack Obama
The Audacity of Hope, pp. 164-165

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Edmund Scientific Company Catalog 645

Thanks to eBay, I have a fresh copy of one of the most important books in my early education. (My worn-out original was discarded in the Great Cleanup of 1973.)

It is Catalog 645 (the mid-1964 catalog) of Edmund Scientific Company, a retailer of educational materials and surplus optics that advertised in magazines such as Mechanix Illustrated. My father took the initiative and sent off for the catalog; then we ordered Lens Kit No. 2 (see second picture below), and, later, some other items, but mostly, I read the catalog, which was chock-full of interesting and useful information.

The company's founder, Norman W. Edmund, was dedicated to science education, and especially stimulating the interest of people just like me — young people with a talent for science, living in a non-college-educated milieu, without ready access to the resources of academia. That is, he wanted to lift people from "technically inclined" to "scientifically inclined." In my case, it certainly worked. That's where I found out there was such a thing as amateur astronomy.

And along the way, he realized, of course, that you can't sell scientific things unless you tell people how they work and how to use them. So the catalog is also a reference book. Edmund brought optics to the masses — prodded lots of gadgeteers like me to learn to design optical systems — by making experimental parts available cheaply. With 30-cent surplus lenses, you can do experiments that you wouldn't do if you had to pay $20 each for custom-ground lenses.

Below are some memorable pages from the catalog.
Click on each image for a much larger, sharper PDF.

As best I can make out, the original company has three successors: Edmund Scientific proper, which now sells new science education materials and lab supplies; Edmund Optics, which sells high-quality optical components; and Anchor Optics, which originally existed to sell off Edmund's huge stock of surplus (generally edge-chipped) lenses at rock-bottom prices, but is now a division of Edmund Optics.

Edmund's popular optics and astronomy books were written and illustrated by Sam Brown, who also wrote about metalworking and who had a distinctive writing style with (when he really gets rolling) two main ideas per sentence. But the marvelous illustrations are what we looked at, not the words. Below are the opening pages from the instructions for Lens Kit No. 2.

Look what a dollar will buy

Speaking of plummeting prices — prices that can go down, and now the market is making them do so — look what I found in a dollar store a few weeks ago. That's right — $1 per packet.

There are still plenty of places where you can pay $5 each for batteries like these. The smaller button cells are labeled alkaline on the box, but the cells themselves are marked "357," which designates a really good silver oxide cell, a slightly improved substitute for the common MS76 camera battery. I don't know if they're really silver oxide, but even if not, they're a bargain. The lithium CR2032 cells are definitely genuine and in good condition. Note the 2010 and 2011 expiration dates; these are not old batteries that someone is unloading.

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Entering the Obama era
(and a quirky school in Macon)

Although I disagree with President-Elect Obama on numerous specific issues, I am glad to congratulate him — and the United States as a whole — for breaking through a long-standing barrier. American politics is truly at a turning point, and I wish him success.

I think that when we carve the 21st Century up into decades, one of them will run from September 11, 2001, to January 20, 2009, especially because we've had not only a change of regime, but a widespread change in political thought, an economic crisis, and a loss of confidence in Reagan-era monetarist economic theory.

My biggest fear is that numerous special-interest groups, some of them with very vague reasons for supporting Obama, are going to be disappointed that he doesn't do exactly what all of them want, all at the same time. There might be quite a bit of whining in six months.

But history is being made, and I have no sympathy for the parents of schoolchildren in Macon, Georgia, who demanded that the school not let their children see the inauguration on TV — nor for the school administrators who acceded to the request!

Why is it that public schools so often seem so eager to grant unreasonable requests? "I don't want my child exposed to" Obama, or Christmas songs, or famous works of art, or what have you, is not a reasonable request. You're saying, "I don't want my child educated." What if a parent said, "I don't want my child exposed to the multiplication table"?

More about the economics of computers

Plummeting prices: Does anybody remember how the price of the TI-99 and Commodore 64 dropped sharply in the period 1982-84? Manufacturing costs were going down sharply due to technical advances, and the economy went into a recession, so the selling prices had to go down too. I think we're seeing something similar today. Prices had the potential to go down, and the market forced them to do so. The big difference is that Commodore 64s were toys for experimenters; minimal Windows XP systems today are tools for doing productive work.

Maybe something similar will happen to the price of health care, too — medical technology ought to get cheaper for the same reason computers do, and current market conditions may force the prices down.

Why Windows 7? Mainly because Vista had an undeserved bad name (mainly from some widely-disliked Apple ads that I can only describe as deceptive) and Microsoft wanted to give the impression they had chucked Vista. Actually, Windows 7 is Vista, redecorated, with numerous ease-of-use improvements.

The challenge Microsoft faces is that people blame Microsoft, not the hardware vendor, when the hardware is defective. Your motherboard may be from Dell or Compaq or somebody's basement in southeast Asia, but if it doesn't run Windows, you blame the maker of Windows. And if Windows won't run an incompetently programmed game that somebody wrote 10 years ago, you blame Microsoft, not the incompetent programmer. A remarkable amount of Microsoft's work in developing Windows has consisted of carefully working around known defects in software and hardware. If the Macintosh has one major technical advantage, it is simply that the same manufacturer controls the hardware and the operating system. MacOS doesn't have to run on motherboards of dubious origin. And it just doesn't have as much software as Windows. There's less bad software because there's less of everything.

Joel Spolsky has some good advice for people who want jobs in the software industry. (Briefly: showcase your technical skills, not your "management" experience.) And more good advice. (Write your résumé in good English, include real information, and don't act like a high-school student, even if you are one.) If jobs are so hard to find, why don't people try harder to get them?

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And here's Windows 7...

Initial impressions of the Windows 7 Beta:

  • Under the hood, it's just like Windows Vista. Only the user interface has changed.
  • That's a good thing, because under the hood, Vista is a good product with a slightly quirky user interface.
  • Security is the same, but security alerts are less pesky.
  • The desktop is even more like the Macintosh than before.
  • AVG Free Antivirus 8 works just fine.
  • .NET Framework 3.5 is included. (Hooray! I've been developing for that version of .NET for some time, and users of my programs have been having to download it.)
  • There are unlikely to be any software incompatibilities between Vista and Windows 7. For that matter, correctly written Windows software since 2000 or earlier should work without problems.

This Notebook entry is the first actual work done under Windows 7. I'm typing it with Notepad++ (an excellent free editor), captured the picture below with Alt-PrtSc, and edited it with Windows Paint, which has been given a nice makeover. (Then, I must confess, both files were given a little more editing after I rebooted into Windows Vista.)

Two important settings for Windows Vista and Windows 7

Just like Windows Vista, Windows 7 needs a couple of settings changed in order for many of us to be at home with it. Open any folder with Windows Explorer, press and release the left Alt key to bring up a menu, and choose Tools, Folder Options. Then:

(1) Check "Always show menus." You'll no longer have to press and release Alt.

(2) Uncheck "Hide extensions of known file types." File names will be shown in full (blah.exe or blah.txt rather than just blah).

(3) Click "OK."

This is a per-user setting; it needs to be done in every account. The defaults for all users can probably be set by Group Policy but I haven't delved into that yet.

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As computer prices plummet...

On Saturday (Jan. 17), Melody and I went over to Silicon Creek (i.e., Gwinnett County) and visited, inter alia, some major computer stores. Recession or no recession, they were packed with customers. The thing to do at Fry's was apparently to push a big shopping cart around with nothing in it; lots of people were doing that.

But the big thing we noticed is that computer prices are really falling. You can get a serviceable (not high-end) Windows XP system for $100 to $300. A really good quad-core system is $1500, which used to be what a low-end desktop PC cost.

And as Jeff Duntemann has pointed out, this is a real threat to the Macintosh because the Mac vs. PC price difference has widened. Just a couple of years ago, Macs and PCs cost essentially the same, if you match the quality of the hardware (Mac uses only high-end stuff; PC gives you cheaper options). Whether the Mac is better, I leave for you to decide. But the point is, there are no $300 Macs.

It is probably also a threat to the Asus Eee, which was meant to be a super-low-cost low-end laptop for the masses. The trouble is, conventional laptops cost about the same now, and the tiny, clumsy Eee no longer has a niche.

Coming attractions

One day of vacation was all Melody and I could afford, and I'll shortly be back in the daily grind, but here are a few notes.

We have acquired the Windows 7 Beta and I'll be reporting on it shortly.

I've also re-acquired one of the most important books from my early education. I refer to Edmund Scientific Company Catalog 645 (mid-1964), from which I learned a lot about applied science. (It's where I found out there was such a thing as amateur astronomy.) More about that later.

And every kitchen needs one of these — a Fluke 61 non-contact thermometer. I bought it to check electrical equipment for hot spots, but Melody and Cathy are likely to claim it as a cooking tool. I've also used it already to check aquariums, right through the glass.

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Happy 800th birthday, Cambridge University!

One of my almae matres is 800 years old this year. The celebrations are beginning today.

In 1209, a group of students migrated from Oxford to found a new school in the market town of Cambridge. The rest is history.

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Highly recommended: ANTS Profiler

ANTS Profiler is a software tool that takes a C# program, or any other .NET application, and tells you how many times each line of the program is executed and how much CPU time it takes. That's how you find out which parts of the program to work on if you want to speed it up.

This afternoon, one of my research assistants tested it and recommended it, and I bought it for the University, and downloaded it, and started using it immediately — it took all of 30 seconds to learn how. It's going to help one of our big projects a lot.

I have no idea why it's called ANTS; I didn't have to read any documentation to get started, so I don't know what they would have told me. But I know it comes from Cambridge, England, and that, in itself, speaks well of it.

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More short notes

I'm still both busy (with a major project) and sick (with bronchitis that has been going on since mid-December), but here are a couple of short notes...

Computer bargains: The latest mailing from Micro Center lists some quite decent refurbished Pentium 4 systems for under $300 (without monitor). (And look at this $88 Windows XP system. Anybody want to outfit a school or youth center?)

We're ordering some new dual- and quad-core computers for the lab from Dell and are finding that you can't spend $2000 on a PC any more. Any reasonable configuration costs less than that. Many years ago, I had a $5000 PC, back when $5000 was real money... and it wasn't wasted; I earned many thousands with it right away. But those days are gone.

What you search on Google isn't private: In several recent cases, police have checked what a person searched on Google in order to tie him to a crime. The information apparently came from data saved on the suspect's computer, not from Google itself. I'm not entirely sure what I think about this. I hope judges and juries would have the sense to realize that ordinary people often search for strange things — especially when wanting background on news stories or detective novels.

Elektor is coming: Europe's best hobby electronics magazine is coming to America.

Happy 91st birthday to our old friend Bob Lucas, of suburban Los Angeles, who claims to be 19 and dyslexic. :)

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Short notes

I said it was busy season... There won't be much here for a few more days.

I've been advocating a national usury law to limit interest rates, and now, so is CNN's Lou Dobbs. Look at the poll results here. 96% in favor, the last time I looked. Admittedly, the sample only covers people who watch Dobbs' show or read his web page, but even so, 96% on one side of the issue is impressive. (The poll will only be on that site for a day or so.)

And here is a piece by Greg Mankiw citing Christina Romer (Obama's top economist) in support of the claim that it's better to cut taxes than to raise spending. One reason is that the money is more likely to be spent on things people actually want. If the government spends money wastefully, GDP goes up (because GDP statistics don't care what the money is spent on) but we don't get anything of value, so we've only benefited on paper, not in real life.

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Busy season

The first work crunch of 2009 is upon us, and entries in the Daily Notebook are going to be sparse for a while. Also, I cannot necessarily answer, or even read, all e-mail sent to me; I'll do the best I can.

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Some perspective on unemployment

Before you panic at the rising unemployment rate, remember that we've just had unusually low unemployment since 1995. Here's the rate from 1973 to the present (from www.bls.gov). Comparing to just the past five years is quite misleading — rates have often been higher than they are now, and we didn't starve.

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Windows Vista: black desktop, mouse cursor still visible

Sharon's laptop crashed the other night due to a battery running down unexpectedly, and when it came up again, it displayed a strange symptom: We could log in normally (using either of 2 accounts), but as soon as the user's desktop came up, the whole desktop was black and featureless, but the mouse cursor (mouse pointer) was still there and moved around normally.

I Googled the problem and found that (1) it is rare, but not unprecedented, and (2) it has no known solution. Some people speculated about video drivers or registry settings.

We had no trouble booting from the restore partition and running the repair tools; they all ran, with no sign of abnormality, but didn't fix the problem. Nor did deleting pagefile.sys.

After a while we removed the hard disk, put it in another computer, copied all the files, and then put it back in the laptop and did a wipe-and-reinstall ("restore to original factory settings").

All I can guess is that Windows' internal data files got corrupted in a way that the repair routines don't fix. I'd like to hear from people with definite, solid information about this problem. Note that I cannot perform further tests (the laptop has been wiped and reinstalled), and there's no point in writing to me with mere speculations.

Nutty about nuts?

Time Magazine has a sensible editorial about the hysteria about peanut allergies that has swept first Europe and then America. Peanuts are banned from entire elementary schools because one student supposedly has a life-threatening allergy. See also this article in BMJ, which inspired the editorial.

Granted, severe peanut allergies do exist. But they are rare. Deaths from nut allergies are about as common as deaths from lightning strikes.

I suspect that, in many cases, "My baby must not get anywhere a peanut or he'll die" is more likely to be an overprotective mother's opinion than a doctor's. Nobody dies from eating one molecule of peanut. The way an allergy works, there is some small amount of exposure that will not harm you, no matter how allergic you are. Some slightly larger amount will produce a detectable response that is not dangerous. And so on. (Ever heard of desensitization?) Indeed, a totally peanut-free environment is more likely to cause children to develop allergies, at least according to some experts.

Further, allergies have a psychological component. Are we talking about peanut allergy or peanut phobia? The way it seems to defy the laws of biochemistry suggests the latter.

The point I would emphasize the most is that peanuts are food, not poison. They are not some strange artificial contaminant. I would feel quite differently if peanuts were new and artificial (like melamine), or if they were harmful in some degree to everyone (like smog or tobacco smoke). But they aren't. They are wholesome and nourishing. Most of us ought to eat them.

Some people can't eat peanuts — just as I can't eat scrambled eggs — but that doesn't give them, or me, the right to dictate everyone else's behavior for (seemingly) miles around. And that is my second point. This is a political issue — it's about how to share power among conflicting people — and a person with a rare allergy does not thereby gain the right to take away others' freedom.

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People to watch out for

Looking back on a quarter-century academic career, I've noticed that there are a few categories of people — generally students — that I have to watch out for, because they're apt to do Odd Things. Specifically:

(1) People who call me "Doc." First sign of a loose cannon...

I don't pay a lot of attention to whether people use the title "Dr." in front of my name. Up North, Ph.D.'s are normally adddressed as "Mr." And of course all my colleagues call me by my first name. "My mama didn't name me Doctor," I explain. But certainly not "Doc."

And not "Daw Ko," which is how one graduate student, years ago, with a rather poor grip on the English language, tried to pronounce "Doctor Covington."

(2) People who can't decide what their name is. Students with this attribute — and I've had several over the years — tend to be profoundly eccentric or even troubled. And hard to keep track of.

Yes, you've probably been called more than one thing in your life. For now, please choose one.

(3) People who don't have names at all. I refer of course to those who want me to know them by fanciful e-mail addresses and science-fiction names.

Maybe you are Zork Dragonslayer in a video game. You're not Zork Dragonslayer in the classroom. And not on the diploma, I hope!

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RAID is no substitute for backups

A major blog-hosting web site, JournalSpace, is out of business due to a disk failure.

They had a high-reliability RAID system which simultaneously maintained copies of everything on more than one disk drive. Failure-proof, right? No...

RAID does not protect you from disasters that destroy the whole machine at once, such as lightning strikes, fires, or floods.

More to the point, RAID does not protect you from accidental changes or deletions because it does not preserve past versions of the data. It only preserves what is on the disk now.

In JournalSpace's case, the deletion may have been malicious. Anyhow, when the RAID system was told to delete the files, it did so — from all the copies of the disk simultaneously — just as it was supposed to.

There is no subsitute for complete off-site backups!

Short notes

Recommended: LeadTools. If you need to do any advanced graphics or video processing in a Windows application, check out LeadTools. I'm using this package to build a custom DVD-burning application for a client right now. The API is COM-based, hence accessible from a great variety of programming languages, and there is a Visual Studio component for doing file conversions (and a great many of LeadTools' operations are conceptualized as file conversions). The LeadTools people are increasing their support for Visual Basic programming, which means C# is only a stone's throw away.

Credit-card companies starve themselves to death: I have long been a harsh critic of the loan-shark practices of the credit-card industry, so I'm not too sad (or surprised) to see them falling upon hard times. Except for one thing: now they're putting the squeeze on customers, and aside from being heartless and bad for the borrowers, that could also be a suicidal move on the part of the lenders themselves.

Remember how mortgage lenders forced people into foreclosure rather than work with them, until they found out the hard way that even foreclosure can't grab money that doesn't exist? I predict a similar collapse of the credit-card industry, and I only hope the harm to customers can be mitigated. Maybe the federal bank bailout should be conditional on freezing credit-card interest rates.

In a couple more days, the 111th Congress will be in session. Hang on to your hats!

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eBay is a buyer's market

Well, so far, my eBay garage sale hasn't brought me great wealth. Someone got a Targus auto-air power adapter (for older laptops) for 25 cents. Even after four or five bids, an elaborate wireless intercom system sold for about $10. Jump in and buy up the last remaining items for pennies on the kilobuck. And buy bargains from other people...

At least these items ended up with people who wanted them, and I got the floor space back.

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How to tackle a big, difficult project

During 2008 I had to tackle several programming projects that were larger in scale than anything I had ever done before. Here are some notes about how I do such things. Much of this will apply to any large creative project, not just programming.

The hard part about starting any large project is figuring out how to do part of it. I am not one of those programmers who write code for six months before hitting "Run." (That would lead to six, twelve, or twenty-four more months of debugging.) Instead, I want to make something work every day. The challenge is how to divide up the project meaningfully so that there can be visible progress, right from the start.

What I do, when I'm programming, is to write a stub — a mock-up of the program with only a tiny bit of the intended functionality. Then I fill in functions one by one.

Another vital step, near the beginning, is to make sure the whole project is possible. Large projects often get stalled because something essential is not actually available and the implementors know this only subconsciously. So an important initial question is: What do I need that is specialized and may not be there? Beginners get into trouble by assuming somebody is going to hand them a neat prepackaged technical solution for every puzzle.

To actually get moving, I usually do some of the easiest parts first. You've probably been told to do the hard parts first, but I don't approach things that way, for several reasons: Doing easy parts serves as a good "warm-up"; it gets them out of the way; and usually, it's not even possible to do the hard parts until the easy parts have been done to provide a framework. It would be like trying to roof a house, just because it's hard, before building the walls.

Finally, my deep realization for this year is that perplexity is normal when you're working on a challenging project. Several times I've felt that I hadn't a clue how I was going to proceed, and then the necessary steps gradually became clearer. Often, I was able to peel off easy parts and do them, leaving the fundamental puzzle smaller and more isolated. Plenty of times, I had to work like an artist, taking time to pace around and think, or go for long walks, or think about the problem "in the background" while doing something seemingly unrelated as "occupational therapy."

I can do a surprising amount of chores while thinking about a programming problem in the background, provided there is nothing that absolutely demands my attention at any particular moment. Ringing telephones, people rushing into the office with questions, etc., break the spell.

It's hard to work by the hour this way, and I was happiest when doing one job, early in the summer, that was defined simply as "a good-faith 2/3-time effort for six weeks."

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What was 2008?

Both personally and nationally, I feel as if I've lived through one of the oddest years in recent history. It may be that when we divide the 21st Century up into decades, we will reckon the first decade as lasting from the 9/11 attack to the election of Obama.

We've certainly seen drastic changes in American politics and economics. The Reagan era has ended with a bang, and the Panic of 2008 (as I think it will be known) has led everyone to re-examine their political and economic philosophy.

It may also lead to colossal blunders. When the government has a glamorous leader and the people want something done, conditions are ideal for making mistakes on a grand scale. What the mistakes will be, I can't quite say; even the most conservative economists seem to be supporting a greatly enlarged role for government in the economy.

On the personal side, this has been an eventful year. Since this isn't Facebook or Twitter, I haven't been reporting all the personal events. Briefly, though, Melody's health has had some troubling ups and downs, although she's better now. I've changed lines of research, although the change took place clumsily — some planned summer funding didn't arrive, but I was fortunate enough to find summer consulting jobs in industry which raised some interesting long-term opportunities. Both daughters are thriving and prospering.

It's 2009; the Panic of 2008 is last year's news; and we're still employed; in fact, I personally haven't experienced any economic hardship at all. It is easy for a recession to become a cultural event spurred on by the news media, a self-propelled snowball of panic. Economists tell us we are apparently in some danger from Keynes' "paradox of thrift" — if everybody stops spending money all at once, they cause others, and even themselves, to lose their jobs.

Count your blessings, grab the bargains in the stores, and have a blessed new year.

The nebula IC 1318 B

I'm clearing the backlog of unprocessed digital images...

IC 1318 B

This is a picture I took from my driveway back in October. It shows a faint nebula in central Cygnus known as IC 1318 B. Some call it the Butterfly Nebula.

This is a stack of nine 4-minute exposures, with darks and flats applied, using an 8-inch telescope at f/6.3 and a Canon EOS 20Da camera. Streakiness is due to the strong contrast enhancement needed to bring out the faint red gas clouds.

The Saturn Nebula, NGC 7009

This fully processed image, a stack of six 4-minute exposures, may look somewhat better than the preliminary version of it that I posted back in October. This nebula of course has nothing to do with Saturn except, by coincidence, its Saturn-like shape.

The enigmatic Crab Nebula

Here's the Crab Nebula, one of the most fascinating objects known to astrophysics, apparently the remains of a supernova that exploded in (as seen from earth) the year 1054. It was discovered in the mid-1700s, at which time it was presumably brighter and more compact than now.

This is a stack of six 5-minute exposures, but corrected with only three dark frames and hence somewhat grainy, taken with the same telescope as the preceding pictures.

See Pete Albrecht's blog, scroll down to "M1 in color," allow time for the pictures to load fully, and mouse over his picture of the Crab Nebula.

High-dynamic-range Orion Nebula

This is my first experiment with the "Merge to HDR" feature in Photoshop. I worked directly from the JPEG files of 5-, 20-, and 80-second exposures of the Orion Nebula with the same telescope and camera as described above. It's a success; you can see the outer parts of the nebula but the center is not whited out. I'm going to try processing this one again, working from the raw files to get more bit depth.

Addendum: Below is a different rendition of the same image, made by just averaging (not HDR-masking) the processed 5-, 20-, and 80-second exposures.

What a leap second sounds like

As often happens, 2008 ended with a "leap second" — the world's master atomic clocks were set back 1 second to better match the slightly irregular rotation of the earth. This happened just before 7:00 p.m. EST.

Click here to hear a recording of the time signals from shortwave radio station WWV (the official U.S. time signal source). Reception wasn't too good, but I managed to record 2 minutes of audio, starting just before the year's final 61-second minute. There's a tick every second, except that ticks 29 and 59 of each minute are sounded only as low-pitched pulses, and some ticks are doubled to convey information about how accurately the earth's rotation is being tracked.

You can verify that there are 61 seconds from the beginning of 23:59 to the beginning of 00:00. They rendered the 60th tick like the 59th, as a low-pitched pulse.

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