Tuesday, December 12, 2017

Christmas trivia...

Christmas trivia...  Last year we bought a new Christmas tree stand, the first one we've ever owned that actually did make it easy to set up our tree.  Click on the image at right to take you to Amazon's page for it.  We got our tree a couple days ago, and once again this year we had it up in just seconds, perfectly straight, with no rusty screws to tighten.  These things are made in Germany, and the mechanical workings are quite clever.  There's a water gauge, too – quite a handy thing, actually, because you no longer have to stick your finger in the water to see where the level is.

Something I saw last year at Home Depot, but stupidly did not buy, is a crazy-long funnel for filling the Christmas tree stand with water.  I rectified that this year – I bought the one pictured at left.  It's about 3 feet long, just the right length to let me stand alongside the tree while I fill the stand.  I've filled it three times so far, and haven't spilled a drop of water yet.  Genius!

And speaking of trees, here's a photo of our tree this year in the dark.  It's a seven-footer, the perfect height for our living room.  The lights on it are the same string of individually-blinking LEDs that we used last year – both of us love those things.  They remind me of the “transformer lights” my dad bought for our tree when I was young.  Those lights ran on 24VAC, and each bulb blinked individually.  Those blinking incandescent bulbs used to be readily available, but not any more – I did find some a few years ago, but they were outrageously expensive and poorly made.  Those bulbs worked mechanically, using a bi-metal strip that bent as it heated and cooled.  The LED string we have uses electronics in each bulb; they should last basically forever.

Just as we did last year, we bought the tree from a family-owned Christmas tree farm from Kalispell, Montana.  Their trees are beautiful specimens well cared for – not at all like the typical junky trees we see at the larger commercial outfits.  One thing we particularly like about their trees is that they have a lot of natural variation.  We like our tree a bit more sparsely branched than most people seem to like, as we want room for the lights and ornaments.  The Robinson family sends a truck and a couple of employees all the way down here to Logan (about 500 miles) each year to sell their trees.  When I looked them up on the Internet, I discovered they have a few other lots they sell from, all in northern Utah.  It's an interesting story.

Those blinking bulbs were originally meant to simulate the really old-fashioned way to put lights on a Christmas tree: with candles.  I remember one Christmas – just one – when I was dispatched to my grandparents house (on the same farm I grew up on) to help with their Christmas tree.  This was while my great-grandmother was still alive and before my grandfather's terrible auto accident, so I'm guessing '58 or '59 – I'd have been 6 or 7 years old, and that feels about right.  I remember clearly just two things about that experience.  First was the tinsel.  It was carefully packed in funny-smelling tissue paper, and had been used in many previous years.  There wasn't a whole lot of it – maybe 50 strands – and my grandmother was very protective of it.  The tinsel was made of very thin, very shiny metal – possibly actual silver (which is what tinsel was originally made of), stored in anti-oxidant tissue.  My great-grandmother and my grandmother carefully placed each individual strand.  I wasn't allow to touch it. :)  The other thing I remember is the candles: dozens and dozens of tiny candles, slightly larger than what you'd see on a birthday cake.  They were in small tin or aluminum holders that hung on the tree.  I lit a few of them myself, carefully supervised.  Can you imagine putting flames on a Christmas tree?  Those candles only burned for 30 minutes or so before they were exhausted, and we stayed right by the tree until they were done – but still.  Flames?!?!

Debbie and some local friends made two beautiful wreaths for our house last Friday.  I keep forgetting to take photos, but finally here they are.  The left-hand one is on our interior kitchen door, the right-hand one on our exterior front door.


Internet vulnerabilities...

Internet vulnerabilities...  Over my career I've been responsible for running several Internet-facing datacenters.  These all ran businesses that were utterly dependent on the Internet, so we paid a lot of attention to failure modes – ways that things could go wrong that would result in a business interruption.  We eventually waded through enough data on actual failures that we could identify three primary concerns.  Together these accounted for all but a tiny percentage of outages actually experienced by real datacenters.  In order, these were (ten years ago; things may have changed):
  1. Backhoes.  Most datacenters are connected to the Internet by just one or two fiber-optic connections.  The most common cause of an Internet outage in a datacenter is a backhoe cutting through one or both of these connections.  Often the failover to the backup connection is inadequately tested, and cutting one cable results in an outage.  Also, all too commonly both connections run in the same underground route, and a single backhoe swipe can sever them both.
  2. Undersea or buried backhaul connections.  That's what this article is all about, focusing on undersea cables.  Buried cables on land are, if anything, even more vulnerable – there are hundreds of miles of them running along Interstate highways and railroad right-of-ways that have nobody guarding them.  A bad actor with a backhoe could sever one in minutes.  A single cable cut wouldn't severely impact the Internet – but cut several carefully chosen cables at once and you could.  This sort of attack is within the capability of any but the most feeble American adversaries, and requires minimal cleverness.  Detailed information like this is readily available to anyone.
  3. NAPs and MAEs.  Network Access Points and Metropolitan Area Exchanges are a largely American phenomenon.  These are the places where major customers connect to the Internet, and where various Internet carriers interconnect with each other.  There are a relatively small number of these, and while they have some security they are not secure against a determined military attack – and certainly not against an artillery or rocket attack.  If you were a well-funded adversary to America, and you wanted to maximize your impact on American commerce and communications ... these would be obvious targets.  
Having pointed out the vulnerabilities, I'd also like to point out something else: the Internet, with all it's redundancies, is not a trivial thing to damage.  You'd have to make quite a few breaks in the system to seriously and broadly impact Internet connectivity in the U.S.  Damaging a particular customer or geographic area is somewhat less difficult.  However, it could be done by a determined (and sufficiently funded) adversary – and I don't immediately see how to defend against such an attack other than by increasing the amount of redundancies and diluting the points of concentration (meaning, mainly, MAEs and NAPs) by making more and smaller interconnections.  The latter is challenging because the economics greatly favor fewer and larger interconnection points...

Monday, December 11, 2017

It's a winter wonderland here...

It's a winter wonderland here ... because of weather conditions that have given us lots of hoar-frost here for the past few days.  I took the photos below yesterday morning, but this morning it looks just like that.  When the fog clears (generally around noon), for an hour or so we have brightly lighted frosted trees (and irrigation pipes, fences, cars, etc.) everywhere in the valley.  We look out the window of our home, or from our car as we drive, and marvel at the beauty all around us.  We've seen this occasionally in the past, but this morning makes the fifth or sixth morning in a row with these sights all around us.  We're driving to Tremonton this morning to pick up our granite shelves, and we're expecting to see this all the way there.

The word “hoar” is derived from the Old English word meaning “venerable” or “august”, itself derived from an Old High German word of similar meaning.  It's pronounced identically to the word “whore” – a word with a notably different meaning.  Last year, while on a drive with a good friend here – a Mormon woman, about 45 years old – I mentioned the beauty of the hoarfrost.  She was absolutely shocked, and could not bring herself to say the word – much to the amusement of Debbie and I.  We found out last week that after that conversation, she went home and looked up the word – she was skeptical of my explanation. :)  This year, she's able to say the word – as now she's certain that I'm not playing a trick on her!

I took the photos below yesterday – the first batch before the fog cleared, the second batch after.  The last photo is a bit different: it shows the shadow of my car on our driveway pavement.  Before the sun broke through, the entire driveway was covered with hoar-frost.  After the sun broke through, the frost on all the unshaded parts of the driveway sublimated within a few minutes.  If you look in the shaded part of that photo, you'll see that the frost is still there – as it is in a thin band around the edge of the shadow, where the frost was so recently exposed to the sun that it had not yet sublimated.  You could measure the time of sublimation by measuring the width of that band and doing a little math, but I didn't think of that in time to make the measurement...


Saturday, December 9, 2017

Best. Illusion. Evah!

Best. Illusion. Evah!  This is a really powerful optical illusion.  All the lines in the image at right are sinusoidal curves.  Yes, even those lines that appear to be triangular.  Click the image to embiggen it, then put a ruler up against the “straight” lines.  They're curved exactly like the ones that appear curved!

Most illusions I can sort of “talk” myself into a state where the illusion disappears.  Not this one.  Much more on it here...

Snowflakes in action...

Snowflakes in action...  A group of Cambridge University students has created a database listing over 1,000 movies that contain scenes of rape, abuse, and sexual harassment.  Their objective was to allow sexual assault survivors to vet what they watch.  A laudable enough goal, though I do wonder whether it's actually a good idea for assault victims to avoid exposure to fictional depictions of things which actually do occur in the real world.  The whole notion of “triggering” strikes me as questionable.

But that's not what caught my eye about the story above.  This did: in that database is the Christmas classic It's A Wonderful Life.  It's cited for a scene of a man chasing a housekeeper while insisting he's in love with her, and another where a woman is being ogled on the street.  Really!  If someone needs to be protected from scenes like that, how could they possibly function in the actual world?

I once read a science fiction story about a human society so uncomfortable with personal interactions that everyone lived alone, isolated, communicating with others only by means they found comfortable.  In the story, a person from a different society came along and basically conquered the world simply because he was willing to knock on doors and confront people face-to-face.  At the time I read this, perhaps 50 years ago, I thought the underlying notion quite far-fetched.  Maybe not...

Sisyphus table in action...

Sisyphus table in action...  And a couple more photos.  The video at right shows the Sisyphus doing an “erase”; it's nearly finished.  The photos below show a few more patterns.

I've had a few questions asked about the table...  The patterns it makes are preprogrammed.  The device comes with a couple dozen patterns, and there is a community where people can share others.  It runs continuously, day and night, though the company says they have plans for a scheduler.  You can control the speed of the ball, and I have it running slowly to minimize the noise (which is nearly zero when slow).  You can make your own patterns simply by creating an SVG file with a single path.  Lots of graphics tools let you make SVG files, but what's most interesting to me is that it's easy to create them in software – they're just specially formatted XML files, which is an especially easy file format to create in a program...




A fun morning...

A fun morning ... is what we have in store.  We're headed first to the Christmas Wish Craft Boutique at the Box Elder County Fairgrounds, then to lunch at The Grille in Tremonton.  I suspect we will be returning with a bunch of craft stuff.  :)

Friday, December 8, 2017

Acceptance...

Acceptance...  Once again this year we were invited to the local LDS church ward's Christmas party.  We went last year, and greatly enjoyed it.  Last night we went for the second year, and enjoyed it just as much.  Mid-way through the experience last night I got to pondering just why I derived so much enjoyment from this event.  It's certainly not the religious aspect, as none of what was being celebrated is meaningful for me.  It wasn't the quality of the production (ward kids doing a Nativity sketch), as from any objective perspective that was simply awful.  Sweet, cute, and full of laughs – but the singing was atrocious, the kids were all over the place, and the plot was hard to discern.  The food was darned good, but we can get great food in lots of places here.  The essence, I think, is that we were amongst friends – lots of them – and neighbors who have accepted us into their community.  Though we don't share their religion and don't behave in ways they approve of, they treat us exactly as though we did.  We count members of this group as our close friends, and vice versa.  Any of these people would help us if we needed it, and we've been able to help some of them when they needed it.  We're part of a real community here, fully accepted into it – and that's what made the evening so enjoyable...

Sisyphus table...

Sisyphus table...  If you're an ancient enough American, you may have learned enough about Greek mythology to have encountered Sisyphus: the king who was being punished by forever rolling a boulder uphill, only to have it roll back down and run over him.  It was the first “Groundhog Day” I ever encountered, only his never ended.

Well over a year ago, a small group with both artists and technologists started a Kickstarter project named after Sisyphus, because their intended product worked by endlessly rolling a boulder (actually a steel ball bearing) around.  They called it a “kinetic art table”; I call it intriguing and beautiful.  Basically it draws patterns in a thin layer of fine white sand – any pattern you want.  When I decided to back this project, for almost $1,000, it was by far the biggest Kickstarter project I'd ever backed – most of them were well under $50.  It felt like a big risk, but everything I read about the team sounded good – and they had a working prototype.  So I took a chance on it.

Yesterday my Sisyphus was delivered.  The company did a beautiful job with it, including in oft-missed details like packing and directions.  I had it unpacked, assembled, and running it's first pattern (at left, below) within 15 minutes.  The center photo below shows it nearly finished with an erase cycle.  At right is a new pattern just barely started (and you can easily see the ball at top center).  It's fascinating to watch it work.  Except for the moving steel ball, the mechanism is completely hidden – if you didn't know how it works, it would look magical, with a steel ball moving in a precise pattern of its own volition. 


So how does it work?  Well, underneath the table is a strong magnet that attracts the steel ball above.  That magnet is moved under the control of a computer (a Raspberry Pi 3B, in fact).  There are two stepper motors and a “rho-theta” positioning mechanism, meaning that the magnet can be positioned at any angle from the center, and at any distance from the center.  That's an interesting choice; the more conventional solution would be an X-Y positioner – but the rho-theta mechanism perfectly suits a round table (an X-Y positioner would fit a rectangular table perfectly).

There is a Sisyphus community that has lots of downloadable patterns – and it's possible to make your own patterns.  I'm going to have some fun with this thing!

Thursday, December 7, 2017

Well, yesterday didn't go quite as expected...

Well, yesterday didn't go quite as expected...  Our house has two furnaces, one that heats the basement and first floor, the other for the second floor.  Last night the temperature got down to 4°F – and both furnaces went on the fritz!  The downstairs furnace is brand-new, just installed a couple of months ago, so I wasn't happy with that situation at all.  However, with a little troubleshooting I figured out that it wasn't the furnace itself that was busted, but rather the external condensate pump.  I just unhooked the pump and put a five gallon bucket under the condensate line, and the heater started working again.  Phew!  Within an hour the house went from 55°F or so up to 70°F where we like to keep it during the daytime in the winter.  Our (wonderful!) HVAC guys showed up just after noon, replaced that condensate pump (after verifying my diagnosis), and then troubleshot the upstairs furnace.  The problem with it turned out to be mineral “growths” of some sort in an odd-shaped plastic chamber that routes condensate away from the manifold pressure sensor.  They got that out and managed to clean it up; slapped it back in the furnace and everything started working.  They're both still working fine this morning (the next day)...

Yesterday morning I visited a lawyer – not something I expected to do in my retirement! :)  I was there with a friend, to sign documents establishing a trust for her and her (many!) children.  It felt rather odd to be in a lawyer's office again – last time I did that, it was as CEO of a public company, back in about 2002.  I've managed to successfully avoid it ever since. :)  One element that made the visit especially odd was the apparent age of the attorney: roughly 12.  This fellow actually graduated from law school in 2014, but he's blessed with a very young-looking face.  He doesn't look old enough to have a driver's license, much less a license to practice law! 

We were quite surprised yesterday when our contractors showed up to work on our retaining walls and walkways.  It was cold outside, well below freezing all day long, and yet these four guys were out there playing in the dirt.  They got the old, temporary, wooden retaining walls removed and started on the footing preparation (compacting, then a layer of road base, then pea gravel, then rock fines).  If they come back today they'll actually be placing rock.   It's way too cold for me to be doing work like that, but somehow they're managing...

Yesterday evening Debbie and I drove down to see the Christmas lights in Ogden's “Christmas Village” and at Willard Bay State Park.  Both were really nice, but my favorite was the Christmas Village.  We just drove around it in the car, but we're going to go down again to park and walk through it.  Highly recommended to anyone who enjoys the spectacle of Christmas lights!