Please create an account to participate in the Slashdot moderation system


Forgot your password?
Slashdot Deals: Deal of the Day - Pay What You Want for the Learn to Code Bundle, includes AngularJS, Python, HTML5, Ruby, and more. ×

Comment James Bond physics (Score 4, Interesting) 211

Heh. My brother and I grew up watching James Bond movies. And obviously, these movies are entertainment and fantasy, not documentary and physics lectures. We all knew that. We all accepted that. But one day my bother went to see a James Bond movie, and he came home positively spitting nails.

It was the the movie where there is a chase scene on skis, so Bond skis down a mountain, and the bottom of the mountain delivers him to the roof of a chalet, and he skis down the roof, and off the edge, and lands on a picnic table, and skis across the table and then keeps on going. And when I say "picnic table", I don't mean a deserted, snow-covered table. The table was laid with a table-cloth and a picnic and people sitting all around. (I don't recall if Bond came off of it with a dinner roll stuffed in his mouth, like a Loony-Toons character).

Anyway. The problem was that my bother skied. And he knew, from painful, first-hand experience, that if you are skiing down a mountain, and you hit just the tiniest bare spot--just the tiniest patch of dirt or rock--it feels like your ski has been grabbed by a bear trap, and you're lucky if you don't tumble right there. Skiing across a picnic table isn't a skill, or a stunt--it's just flat impossible.

Bond movies are unrealistic, yes, but this one was unrealistic in a way that he couldn't accept. And it killed the movie for him.

Comment I had this problem with heat maps (Score 1) 28

I programmed some heat maps once.
Grey-scale is no problem: you map the data range into 0-255 and you get nice grey scales.
Color was tricky.
If you just ramp the RGB values from red to green to blue, you don't get smooth color gradients.
Instead, you get all red up to the 1/3 point, and then all green from 1/3 to 2/3, and then all blue.
Right where the colors change over there are thin strips where one color shades into the next.
I had to twiddle the mapping function to stretch out those strips of shading in order to get a smooth color gradient across the entire data range.

Comment It's easier to think than to do it (Score 1) 126

I was helping my son with his math homework.
It was factoring polynomials: stuff like x^2 + 5x + 6 -> (x+2)(x+3)
He basically had the mechanics down.
He looked at the next problem, and picked up his pencil to start grinding his way into it.
Without thinking, I slapped my hand down on the place where he was about to start writing, and said, "No! It's easier to think than to do it."
And he thought, and he wrote down the answer.

Comment Blister packaging (Score 3, Interesting) 498

The UK used to sell acetaminophen (AKA Tylenol) in bottles (like in the US).
Some people committed suicide by OD'ing on the pills.
So they changed from bottles to blister packs.
Now if you want to off yourself that way, you have to sit there and pop out ~50 pills, one by one.
It reduced those sucides by something like 30%.

That's a lot of lives saved, with a pretty low barrier.

Comment Re:just FYI (Score 1) 77

Heh...if this is the drug I'm thinking of... ...ATP inhibitor...imbalance in the proton gradient...

What it does is leak protons across the mitochondrial membrane, which is tantamount to creating an internal short circuit in a battery.
You know, like those Lithiuum-ion batteries that sometimes spontaneously combust.

One of the first things the FDA did after it was established was get this stuff off the market.

Comment My 5-year rule (Score 4, Interesting) 958

The first time I had to make real decisions for myself was when I started living on my own in my early twenties.
I was aware that there studies on diet and health, and that there were dietary recommendations based on those studies.
I also knew that those recommendations had change over time.
So I decided that I wasn't going to turn my life upside-down over this stuff until the recommendations stopped changing for at least--I picked a number--five years.
Even at the time, I knew that this was mostly a self-serving rationalization for me to just keep eating the foods I liked.

As the years went by, I watched with growing astonishment as the fads (in science!) came and went; diets swirling around them like groupies, or celebrities.
Nothing has ever stayed settled for more than five years in a row.
I've never been called on my original committment/rationalization.
It's been over 30 years now.

Comment Job postings are cheap (Score 2) 38

Long ago, I worked for a little company in one state, that bought a big company in another state (don't ask), and the big company had a union shop. At some point they were trying to negotiate something with the union, and they weren't getting what they wanted, so the next week they advertise 300 job openings in the local city paper, like they were going to move the entire shop in-state and just cut the union loose.

Nothing ever came of it.

Comment Re:A bell curve! (Score 1) 169

The bump is an artifact of the intervals: the last interval is much larger than the others.
If it continued 100-109, 110-119, etc. then the bell shape would probably continue too.

"If I do not want others to quote me, I do not speak." -- Phil Wayne