My company makes it easy to give blood: every 6 weeks (or whatever it is), the Big Red Bus pulls up in the parking lot. I take advantage of the opportunity whenever I can.

Today was my first chance since I started working out at Christmas. My blood pressure is down to 90/60 (although it was never high to begin with; I was usually 115/70 or so) and they could actually find my center vein, so I bled quickly and I was done in just a few minutes.

The Bus, though... it used to be a giant travel bus, like a Greyhound. Now it's more like a big fire rescue truck. It's thinner, shorter, and taller. There's probably more room for stuff, but the techs have to reach up higher for it. There's less room for writing or sitting. I've always had to bend my knees to fit in the donation seat, but it seemed more cramped today, and the tech had to place the collection bags on my leg while she put the stickers on.

The worst part, though: they have to keep the juice outside in a cooler! On the old bus, you'd sit down and some pretty nurse would offer to bring you a drink. On the new bus, no drink for you! When you're done giving blood, you have to go outside and get your own.

The technicians were wonderful. But I really want my old bus back.

Not only is summer starting, along with all the scheduling problems that involves, but Silent E has been acting up, too. For the past few weeks the driver's front wheel bearing has been squeaking. It sounds like I'm powering the car with guinea pigs.

Last weekend I took it down to Goodyear to have the bearing replaced. I decided to try a new place because the mechanic at the mom-and-pop place I usually like ignored all my advice, driving faster than I've ever been and forgetting to plug it in afterwards.

At Goodyear they looked me right in the eyes, listened to everything I said, and wrote it down for later reference. If only the repair itself could have gone so smoothly.

Continue reading "Judebert's EV Conversion Diary: Wheel Bearings"

I know I've been neglecting my blogs lately. And my online forums. And FaceBook. I apologize.

I've been working on a neat little puzzle game. Not a "puzzle game" like Bejeweled or those other match-up toys. Something that actually requires a little bit of thought, like Sudoku or Griddlers, but more logic. I've got a prototype, but I'm not ready to release it just yet; I promise to let you know when it's ready.

What's taken me so long is the mathematical whirlwind I've immersed myself in. It's been delightful. (Yes, the Alpha Geek enjoys math.) For a rather minor aspect of the coding, I needed a way to sum any pair of 36 possible numbers and guarantee that the result was unique for that pair. (In mathematical terms, I needed a set such that a_i + a_j is distinct for all i < j.) I searched online for days before finding what I need: weak Sidon sets, also known as "well-spread sets" or S₂ sets.

It turns out that nobody has published any weak Sidon sequences of any appreciable length, though. I needed to write a program to generate them.

My first try turned up a 36-member set and a 100-member set in short order. But I wanted smaller numbers, so I programmed more exhaustive search methods. One of them ran for 36 hours before Kayla decided to log me out, destroying all my progress.

So I modified the program. It now finds all well-spread sequences of a particular length chosen from the set of integers smaller than a specified maximum. And it saves its progress, so if I'm ever interrupted again, I can simply resume. I can even run on multiple computers by generating new start states (although of course I'll have to quit one of the programs manually).

When I've got my first set of sequences, I'll publish my results and my program. I just thought you should know why you haven't heard much from me.

I know it's been a while; I've been busy! The visit with Omi and Opi is over, and life has gone back to what passes for normal around here.

But the big attraction right now is my kids.

Tatiana graduated from 3 years of middle school with all straight As. She's been working hard for that! And her teachers awarded her the "good character" award for the second time. Congratulations, Tatiana!

(I would also like to record for posterity that I have promised my daughter Tatiana that if she graduates from the 9th grade pre-IB program with straight As, and chooses to move on to the IB program, I will purchase her a laptop computer of modern specifications which she will continue to own until she drops out of the IB program.)

Melissa is moving on to middle school, again with straight As. She scored the highest possible score on both her FCAT Writes and FCAT Reads: 5! Congratulations, Melissa!

Kayla is attending Tuskawilla Montessori's 1st - 3rd grade class next year. She's improved quite a lot in listening to her teachers. She took some CATs this year, and fell in the 98th - 99th percentile in every category! Her reading grade level is 3.5! Congratulations, Melissa!

Congratulations, kids! I'm proud of all of you!

My sister-in-law needed to leave town for two weeks. Since she's the only family member who lives near my parents-in-law, they'd be alone with no one to help them. (He has Alzheimer's, and she's developing some form of senility.)

Since we're the only other family in sight, Eri and I got two days to prepare the house for them.

Our house is legendarily messy. Essentially, we needed to babyproof the master bedroom and bath, then get all the projects and mail off the kitchen table. We also needed to clean up anything Opi could see from his chair, since he'd just forget about having complained only minutes ago.

Naturally, these are not free weeks for us: we've got lots of obligations to meet.

We managed to get the rooms swapped around and minimally acceptable. There's way too much mess everywhere: Opi keeps pushing stuff around with his cane and telling us, "Schmutz." (It means "mess" in German.) Eri jokes that she's going to put a broom on the end of his cane.

Originally, I was really upset about this, but determined to make it work out. And yes, it's been quite difficult, but things are working out. We're managing to fulfill all our obligations, thanks largely to friends like Jim & Melissa. And we're having some fun, too. Omi is even helping me prepare for The Amazing Race by teaching me some German.

Only a week and a half to go! We'll have everything back to normal in no time.