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Daily Notebook
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2010 June 30 |
Mid-year checkpoint We've made it halfway through 2010, and I'm going to close out the month early by uploading the June 30 entry on June 28. Here are a few short notes. How things go wrong, part 1: The distinction between "income affluent" (IA) and "balance-sheet affluent" (BA) is useful; yuppies are the former, especially yuppies who go bankrupt. Article here. How things go wrong, part 2: Here is a useful study of how a culture of rulebreaking can entrench itself. I've seen things like this happen in the computer security field. It often happens in business. There are people who try to make it happen in every high school and youth organization. (Thanks to Jeff Duntemann for the link.) Recommended: Bell "Traveler" car compass. I've just put these into two of our cars. They have adjustments to counteract the magnetic field of the car, as well as another adjustment for the exact direction of the north magnetic pole. Today, as I waited at a red light on Lumpkin Street, I could see my compass twitch from the magnetic field of another car as it passed by. Achieved: The University of Georgia has moved 85,000 users to a new mail server. With 35,000 students and 15,000 employes, how do they get 85,000 users? I think they're suffering user bloat — accounts are created and never cancelled, consuming resources forever. Anyhow, Microsoft is now hosting e-mail for us — in Texas! — and we are allowed (I think) 10 GB instead of 20 MB of storage. (Finally!) All the old mail was copied over, with only one untoward result. They copied all the mail 10 days ago, and then, during the changeover, copied all the new mail (a much smaller batch). However, they didn't delete copies of the old mail that had disappeared from the old server during its final ten days. In my case, that made 500 messages reappear because I had done a really major clean-up during the interval. Fortunately it didn't take long to do it again. |
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2010 June 29 |
What if I don't pay this one? A common computer programming mistake in the 1960s was to have computers send out bills for $0.00 and demand payment, even claiming that it was past due. Typically the problem was that a small rounding error, less than one cent, was still present in the customer's balance. Or maybe the programmer just didn't notice that zero is different from other numbers.
At first glance it would seem that they're doing it again. Actually, this bill serves a purpose — it tells me the account was completely paid off last month. But it's odd to talk about "paying" it. And a couple of my credit cards get mysterious, unlabeled charges of $0.00 about once a month when I download transactions in Quicken. |
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2010 June 27-28 |
How sheep go astray Dr. Simms' sermon this morning (June 27) made an interesting point about search algorithms and planning. We've all heard of going astray like sheep. But why and how do sheep go astray? Simple. They keep their heads down, moving from one bunch of grass to another without any long-range planning or navigation. People do the same thing, and even robots and computers... |
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2010 June 26 |
Kluge of the day: In days of old, web pages were written in plain HTML, keeping everything as simple as possible. If you try that today, your web page won't look very good — it will be in a default typeface that probably looks grungy, and it will not have margins at the left and right. The other day I needed to make a web page very quickly in plain HTML. I'm about to show you how I did it. Critics: I already know this isn't sophisticated. Its purpose is to look reasonably good in the browser (even very old browsers), not to impress HTML gurus. The HTML community seems to be unusually infested with "language lawyers" who rush to tell you that you shouldn't do something that works perfectly well because a new way of doing it was invented last week and is now the standard. The most improvised thing there is the row of symbols for margins. I know it's improvised, and that you can easily specify table cell widths in pixels, but it works. To view the whole page that I made (which is a cut-down version of one of our lab documentation pages), click here. The source code looks like this; feel free to copy it.
This super-simple format might be useful, not only for human beings in a hurry, but also people starting to learn HTML and for web pages written by software. More lunar colors
More lunar colors — same technique as the other day, recording video with my 5-inch telescope. This time you're looking at the crater Aristarchus, which has a reputation for strange goings-on; it apparently has minerals that reflect light very differently depending on the way sunlight is striking them. |
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2010 June 23-24 |
Colors of the moon
This shows that my DFK planetary camera has relatively little color noise or crossover. You're looking at the moon — a region known as Sinus Iridum — and I've turned up the color saturation to bring out subtle variations in the color of the surface. This was taken by recording about 3500 frames of video with a 5-inch telescope and aligning and stacking the best 3000 or so. |
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2010 June 21-22 |
Miscellany Although administrators say no furloughs are planned, my contract (which I received and signed today) says that up to 10 furlough days are possible. (Remember, at this time last year there were not yet any definite plans to furlough us, but they did it.) I hope that clause doesn't become a permanent fixture. Death by PowerPoint: Click through and read it. I especially deplore people who use PowerPoint as a prompter, i.e., just to display their own list of reminders of what to talk about — not comprehensible to the audience. (Those are the people who will talk for 30 minutes from one slide that says "Features and Benefits.") People say I give good PowerPoints. I do this by disregarding traditional PowerPoint culture. I always make the slides completely understandable so that they stand on their own. Many of the PowerPoint gurus say never to do that. But then, a lot of people spend their time teaching each other how to give bad presentations, like Atlantans teaching each other how (not) to drive on freeways. If you've always wanted an IBM 360-series computer of your own, check out Sim390, and see how little computer power it requires. The only operating system provided with it is McGill University's MUSIC. But the price is right — free! |
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2010 June 20 |
Three disconcerting things and one welcome development Disconcerting thing #1: The weather. The reason there hasn't been much astrophotography here is not just that I'm hard at work on other things. It's that we're having an endless series of partly cloudy days and late afternoon thunderstorms. And, of course, a bumper crop of mosquitoes. Disconcerting thing #2: A 1-watt laser being promoted as a dangerous toy. Details here and here. One watt is 1000 times the usual power of a laser pointer. Or is this a hoax or publicity stunt? Disconcerting thing #3: The University of Georgia rakes in the money when students get Bank of America credit cards, even though abuse of credit cards by students is a serious problem (and, nationally, has even led to suicides). We found out about this because new laws no longer let them keep it secret. In my opinion, except for well-supervised student loan programs, it makes no sense to lend money to people who don't have an income. Welcome development: Regulations are about to kick in to keep credit card companies from charging excessive penalties. Penalties will now be capped at $25 or the amount of the violation, whichever is less. Go $2 over the credit limit and they can only hit you with a $2 fee. This is the end of the $44 trip to Starbucks. |
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2010 June 19 |
No more furloughs Although I haven't actually received my 2010-11 academic year employment contract yet, we've been assured that there won't be any more furloughs. Recall that in 2010-11, we were furloughed (laid off) for 6 days to reduce the University's expenses. This created a strange situation since there were days on which we were forbidden to work for the University. |
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2010 June 18 |
System administration gets easier At the Institute, we've been using Windows with roaming user profiles since 2001. That is, we have it set up so you can sit down at any PC, log on, and get your own desktop and files. Over the years, Microsoft has gradually made this kind of setup easier to administer. And today I had a pleasant surprise. The default settings for newly created accounts traditionally come from a folder called Default User on the domain controller. There is an intricate procedure for copying a real user's profile to that location. It has to be done twice, once for Windows 2000-2003-XP-2008 and once for Vista and Windows 7. And you had to go through a pesky process of hunting down, and deleting, unwanted user-specific information that might be in the profile. Well, as I sat down to do it today, I was gratified to learn that the current recommendation is not to do it (see also this and especially this). There is still a roundabout way to do it via Sysprep, but normally, you deliver a lot of settings via Group Policy (including some that can be reset by the user), and Windows takes care of the defaults. So I gleefully filled in the appropriate Group Policies and deleted the Default User folders from sysvol (netlogon). (The OS still has its Default User folder in the original place, of course.) |
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2010 June 17 |
Is this Windows error message backwards? Event 1509: "Windows cannot copy file A to location B. This error may be caused by network problems or insufficient security rights."
I spent a long time troubleshooting this problem on one of our PCs at the lab and, as best I could determine, at the time, Windows was copying from C: to \\AIHV, not the other way around. A roaming user was logging out. I post this just in case somebody else is perplexed by the same thing. |
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2010 June 15-16 |
Miscellany I've been advised that gasometers are called "gasholders" in the U.S. as well as Great Britain. Apparently "gasometer" is more a Continental term. Some time back I wrote about the Windows U.S.-International keyboard layout, which makes it easy to type several foreign languages. Now I learn that you can make your own keyboard layouts too, with Microsoft Keyboard Layout Creator. Has anyone done Classical Latin (with long-vowel marks)? And if you're going to get rid of a PC on which you've done online banking or handled other confidential data, you need SDelete (freeware). This is a utility that writes over the space formerly occupied by deleted files, so that nothing can be retrieved. Remember, deleting a file does not really erase it — it just marks the space as ready for reuse. That is true whether or not you use Windows' Recycle Bin. |
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2010 June 14 |
Least surprising news story of the week The BBC reports that pornographic web sites are rife with credit card fraud, viruses, and malware. Everybody else has known this for 15 years. |
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2010 June 13 |
What I actually do for a living While working on a consulting project today, I had an insight about what I do for a living. I manage and overcome cognitive overload. Of course I do a lot of other things too (such as teaching and even system administration), but that's the core of it. What I mean by that is that I take creative tasks that are almost too complicated for a person to do, and I do them. I achieve this by breaking them up in creative and felicitous ways. My motto: "If you can't do the whole thing, do part of it. Then do the rest of it." My favorite tasks are writing books and creating large computer programs. Unlike building a house or running a bank, these tasks can't be "managed" in the usual way, because (a) they don't divide up among multiple people, and (b) nobody knows in advance how to do them. Think about it. When you build a house, the builder knows in advance exactly what needs to be done. It's been done many times before. All the well-understood parts of it can be divided up among different workers with different specialties. So managing the construction of a house is basically a matter of knowing how it was done many times in the past, and making the same thing happen again. It's almost like an assembly line. Writing a book is not like that. Nobody knows what's in it until it's written. Nor does it usually divide up neatly into tasks for different people. The author has to create the book, and there is little or no difference between designing it (in detail) and building it. Writing a computer program is the same way, and maybe more so. There is no difference between designing it (in detail) and building it. There are those who would like to "manage" software development the way we manage house-building or other familiar business activities. But I side with the purists, such as Dijkstra and Wirth, who maintain that computer programming can't be "managed" because it is totally creative — anything predictable would immediately be automated and would no longer be part of the job. Painting a room of a house is drudge-work; you know in advance exactly what to do. But in computer programming, once you know exactly how to do something, it's done! |
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2010 June 12 |
Alternative reading Stop reading this boring blog, which I'm too busy to keep up properly, and read Home Inspection Nightmares instead. I hope to return to blog-writing in a day or two. Also, if you have an ounce of curiosity left about the Atlanta gasometer, read the revisions to yesterday's entry. |
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2010 June 10-11 |
Trivia For those who really want to know, the Atlanta gasometers (there used to be two) can also be seen in this picture (upper left corner) and this one (lower left). They were roughly where Centennial Olympic Park Drive crosses Mitchell street (I think). That enormous railroad yard has become parking lots and space for new construction. Subsequent examination of even more photographs, such as this one, leads me to conclude that the position of the last surviving gasometer corresponds to the southwest corner of the present Philips Arena, at Philips Drive and Centennial Olympic Park Drive. I can't recall ever having seen the Atlanta gasometer myself; I am merely spurred on by correspondents, and fascinated by the fact that I can research these things over the Internet! This old Sanborn Fire Insurance Map shows two gasometers there. This map suggests there may have been yet another one a few blocks to the south. Thanks to Tom Roderick for the links. News from the world of real estate: Now that short sales are common, is it any surprise that some of them are fraudulent? Secondhand smoke damages mental health? That's the surprising conclusion of this research study. (Contrary to the flurry of foolish comments that turned up on one of the media sites, this is not a politically motivated study, not an evil conspiracy, and the researchers probably didn't even expect the result that they got.) Obviously, more work is needed, but the point is, nicotine is a neurotoxin, and unlike smokers, secondhand-smoke victims (1) are not self-medicating (they're not taking nicotine to relieve symptoms of a problem that is already present), and (2) are not smoking voluntarily at all (which means they probably include people for whom nicotine is particularly harmful, who are instinctively trying to stay away from it). Could it be that smokers are a self-selected population of people who are relatively immune to nicotine, and it's more harmful to the rest of us than to them? |
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2010 June 9 |
Why gasometers intrigue us Further to the last two entries, I think the reason gasometers intrigue us is that we ignore them until they're gone or radically changed. They have a very distinctive appearance, and because the cylinder top rises and falls, we often see them as stark skeletons even before they're dismantled. We train ourselves to ignore them, but they're part of the urban background. Recommended: Skype Preparing for an upcoming teleconference, I've finally joined Skype, the Internet telephony service. You use your computer (with headset) to make calls to other subscribers, free of charge. For a (rather low) price, you can also call regular telephone numbers (in quite a few countries). What surprised me about Skype was the high quality of the audio. Remember how analog telephones sounded twenty years ago? This is better. In the meantime we've gotten used to digitally compressed sound on cell phones, especially those with weak connections. Skype can compress audio, of course, but with modern high-speed Internet connections, it doesn't have to. |
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2010 June 8 |
There was one in Atlanta too Not one but two correspondents have written to tell me there was a gasholder (gasometer) in Atlanta, complete with rising and falling cylinder, through about 1970. You can see it by clicking here. Near the middle of the left edge, a long straight bridge enters the picture. Right behind the bridge is a black cylindrical gasholder. |
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2010 June 6-7 |
The King's Cross gasholder skeletons It's been six years since I've been to England. When I go there, I always pass through the King's Cross Station area a lot, since that's where the trains leave London for Cambridge. (And also Hogwarts. But I use Platform 9B, not 9 3/4.) One welcome bit of news is that the station across the street, King's Cross Thameslink, is no more (see also here). That's where trains from Gatwick Airport used to come in, and I had to carry my luggage up a long staircase. Now those trains come into St. Pancras, which connects with King's Cross, presumably without any long staircases (though I haven't checked). Another thing I've just learned is the story behind the huge cylinder-skeletons made of steel beams as tall as eight-storey buildings. I recall seeing these scattered across England, but especially near King's Cross, and being told that they were the remains of gas tanks. They are in fact a famous set of "gasholders" ("gasometers"), Victorian-era tanks for storing gas near atmospheric pressure. Intact, they consist of a cylinder with a movable top that serves as a piston. The height of the whole cylinder varies as it is filled and emptied, so if it's empty, it won't be as tall as the metal skeleton around it. The ones at King's Cross are considered historic landmarks and are going to be reassembled, probably with apartment buildings inside. In the movie The Ladykillers you get a glimpse of the King's Cross gasholders before they were reduced to skeletons. Click here for a picture of one that is still intact today. Below, you see just the skeleton.
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2010 June 5 |
Saturn, enhanced
This is the same Saturn picture with the color saturation turned up. It may remind you of a colorful Voyager space probe picture of Saturn a few years ago that had been processed in the same way. |
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2010 June 3-4 |
DFK camera does Saturn
Here's my first planet image taken with the ImagingSource DFK camera. The air was very unsteady. I took about 2200 frames of video and stacked about the best 1500 of them. Unlike my older planetary camera, the DFK allows me to take longer exposures (in this case 1/9 second at f/20) and use a lower frame rate (7.5 fps in this case, though it will go down to 3.75, and will also do still pictures). This is a lower magnification than my earlier Saturn pictures. But look at the gradation and subtle color in the bands. |
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2010 June 2 |
Like moving a cemetery My main sysadmin task right now consists of moving all the users' files from a virtual disk to a real disk. A virtual disk is a disk drive that resides in a big file on a real disk. It's a handy way to set aside a fixed amount of space and make it act like another disk drive. The problem is, you can't do a full "bare metal" backup of a real disk that contains a virtual disk that is in use by the same computer. So we're getting rid of the virtual disk. And it's a remarkably slow process. The procedure is to back up the users' files to an external disk, then restore them to the new location (preserving all security attributes). The backup was a block operation and was relatively quick. The restore operation is much slower because it's a file-by-file operation; all the directory structure has to be created. We're talking about 3 hours one way and 20 hours the other way, roughly. But it would have been even slower if I hadn't caught something during a preliminary run. One of our users, who left a couple of years ago, had one million small text files! They were the input to a text-classification program; perfectly legitimate; but it would have taken a tremendously long time to move them because of the need to create a million directory entries. |
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2010 June 1 |
What? Another month already?! I've been even busier than anticipated lately... Notebook entries are going to be a bit sparse. Instead, read Jeff's. Some thoughts about system administration I've suddenly taken over sysadmin duties for our new server, which is not quite completely set up. Some thoughts about system administration:
Many sysadmins stay in low-paying jobs forever because they disregard the third point. If you make yourself The Only Person Who Knows, and hence The Only Person Who Can Do This Job, you can never be promoted! |
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This is a private web page,
not hosted or sponsored by the University of Georgia. Entries are most often uploaded around 0000 UT on the date given, which is the previous evening in the United States. When I'm busy, entries are generally shorter and are uploaded as much as a whole day in advance. Minor corrections are often uploaded the following day. If you see a minor error, please look again a day later to see if it has been corrected. In compliance with U.S. FTC guidelines, I am glad to point out that unless explicitly indicated, I do not receive payments, free merchandise, or other remuneration for reviewing or mentioning products on this web site. I have a Canon EOS 20Da camera and a Tektronix TDS 210A oscilloscope on long-term loan from their manufacturers. Other reviewed products are usually things I purchased for my own use, or occasionally items lent to me briefly by manufacturers and described as such. |