Today I Learned

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In summary: Today I learned that Lagrange was Italian and that he lamented the execution of Lavoisier in France during the French Revolution with the quote:"It took them only an instant to cut off this head and a hundred years might not suffice to reproduce it's...brains."
  • #4,166
DaveE said:
Yes, me too. I was sooo much smarter 30 years ago. I knew a bunch of stuff I never used much, or ever, which has now drifted away.

But, a couple of related points.

1) This is the sort of problem that can have several solutions from simple (buy the right instrument) to complex (PLLs to filter, demodulate and sample etc.). Which are really based on how much you care, how hard is the problem, and how much time and money you have. This causes a bit of confusion to people that understand the options but not the all of the constraints.

Which leads us to:

2) Working engineers are working. They will spend much more time and effort thinking about their specific problems than we will. When I was actually paid for this sort of thing I probably would have spent at least a day thinking about the solution, sometimes much more. OTOH, we won't. We toss out ideas based on our previous experience, learned by actually solving these things. If you cared more because this was your problem, not someone else's, you would sort all of that out.
Thanks for the corroboration. Forty to fifty years since my hands-on RF lab work. Your second point contains the corollary that inputs from another engineer not invested in the outcome can help clarify one's thinking; true for many professions such as medical diagnostics.

Good point about cost as an aspect of problem solving. Scale also limits solution sets. For example, I would design a full-scale data center with an ATS (automatic transfer switch) between municipal power and emergency generators, while a DIY homeowner might rely on manual switching.
 
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  • #4,167
TIL an interesting bit of information. I was reading an article from this month's Scientific American about When Animals Started Making Noise. Near the end, the discussion went into how humans were unique in the animal kingdom for their ability to teach each other language. The sign language statement from the chimp at the end of the paragraph left me floored.
It is not just the possession of language that is so powerful: humans are unique in their abilities to teach, learn and record language. Although researchers have successfully taught some other primates to use sign language, none of these educated apes has ever taught this language to others of its species, even when given the opportunity. In one case, a chimpanzee at the Duke University primate facility who had been taught sign language was reunited with his troupe. He tried to use his new skill set to communicate with his fellow chimps. After a week of attempts, his keepers found him in a corner of the paddock, where he had isolated himself. When they asked him in sign language why he was not with the other chimps, he signed back, “Because they are insects.”
 
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  • #4,168
Borg said:
TIL an interesting bit of information. I was reading an article from this month's Scientific American about When Animals Started Making Noise. Near the end, the discussion went into how humans were unique in the animal kingdom for their ability to teach each other language. The sign language statement from the chimp at the end of the paragraph left me floored.

Aha. I bet if you taught a group of apes to sign, they would be able to teach others who wish to join the group.
 
  • #4,169
Hornbein said:
Aha. I bet if you taught a group of apes to sign, they would be able to teach others who wish to join the group.
I don't know. Using a tool isn't the same thing as creating it.
 
  • #4,170
Hornbein said:
Aha. I bet if you taught a group of apes to sign, they would be able to teach others who wish to join the group.

Ool? Bobo!

1642808528654.png

https://haphazardstuff.com/caveman-1981-movie-review/
 
  • #4,171
TIL that the best way to paint a wood paling fence is before you nail all the palings up 🤦‍♂️

I also learned that colour selection is impossible! Tiny swatches, terrible store lighting, expensive sample pots, and marketing names that have nothing to do with reality. It's a choice nightmare :nb)
 
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  • #4,172
Melbourne Guy said:
I also learned that colour selection is impossible! Tiny swatches, terrible store lighting, expensive sample pots, and marketing names that have nothing to do with reality. It's a choice nightmare
When we moved into our house, the downstairs bathroom was painted an off-white, but a nasty one that looked sort of dilute nicotine yellow. We decided a light colour was good but the yellow was ugly, so we went out and bought three sample pots in blue, green and brown tinted off-whites. I painted three patches, left them to dry, and found that there were only two patches because our nice brown tinted off-white turned out to be identical to the nasty nicotine yellow tinted one. Fortunately the blue tinted one was nice.
 
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  • #4,173
Sample paints are on the agenda for me today. We're getting ready to paint the kitchen a new color. :oldsmile:
 
  • #4,174
Borg said:
Sample paints are on the agenda for me today. We're getting ready to paint the kitchen a new color. :oldsmile:
When my daughter was a toddler, she managed to paint a large part of the "play room" in raspberry spots - I think it was by sneezing into her drinking cup. You won't find that scheme in sample paints!
 
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  • #4,175
TIL about the absolute 'destined to lose' situation: colds lasts 4-5 days, but if you use a nasal spray that long, what you are up to is a rebound congestion.
Does not feels good.
 
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  • #4,176
Yesterday I learned that Roger Penrose once sued a toilet paper manufacturer for using his Penrose tiling without permission.

A Penrose tiling is infinite but non-periodic (never repeats itself), so, when embossed on a roll of paper, would reduce the chances of adjacent sheets sticking together.

Ref: Toilet Paper Plagiarism
 
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  • #4,177
Ibix said:
When we moved into our house, the downstairs bathroom was painted an off-white, but a nasty one that looked sort of dilute nicotine yellow. We decided a light colour was good but the yellow was ugly, so we went out and bought three sample pots in blue, green and brown tinted off-whites. I painted three patches, left them to dry, and found that there were only two patches because our nice brown tinted off-white turned out to be identical to the nasty nicotine yellow tinted one. Fortunately the blue tinted one was nice.

The contractor who helped me fix up my current abode found a solution to this color problem.

Pure white walls appear stark, excessively bright, and easily show dirt and stains.
Adding yellow can result in an aged, literally 'yellowed', appearance unpleasant to many people.

The contractor added red to a flat white base achieving a mellow rose tint pleasing to the eye that hides or deemphasizes basic stains. I forget the name of the red pigment, but the resultant tint remains popular in American southwest and Mexican interiors. The rose color matches light or 'oak' wooden floors and wooden furniture. We painted ceiling, doors and mouldings in white semi-gloss that compliment the rose walls.

The blue solution also works well, particularly in bedrooms and bathrooms, also matching wood wainscoting and floors.
 
  • #4,178
Klystron said:
The contractor added red to a flat white base achieving a mellow rose tint pleasing to the eye that hides or deemphasizes basic stains. I forget the name of the red pigment, but the resultant tint remains popular in American southwest and Mexican interiors. The rose color matches light or 'oak' wooden floors and wooden furniture.
Magnolia? That's the standard "neutral" colour that everyone here paints their house when they're trying to sell it. A lot of the walls here are magnolia because the previous owners did that (it belonged to their mother and I think the original colour scheme reflected a unique taste, shall we say) and I've no particular urge to repaint them. The bathroom was a slightly different colour, though, and rather ugly.
 
  • #4,179
Ibix said:
Magnolia? That's the standard "neutral" colour that everyone here paints their house when they're trying to sell it. A lot of the walls here are magnolia because the previous owners did that (it belonged to their mother and I think the original colour scheme reflected a unique taste, shall we say) and I've no particular urge to repaint them. The bathroom was a slightly different colour, though, and rather ugly.
Hmm... Magnolia appears to be a cream color. The white paint can is labelled 'eggshell'. The red additive can has a list of numbers without a descriptive label. The painter mixed the colors at the paint store then brought the 'rose' tint in the original 'eggshell' gallon cans. I will ask the painter what they call the result.
 
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Jonathan Scott said:
paint a large part of the "play room" in raspberry spots - I think it was by sneezing into her drinking cup
A baby experimentalist.
 
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That color approximately is the current color of the sky where I am. The local temperature is 25 degrees F.
 
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  • #4,183
TIL that NFL "Long Snappers" have developed the amazing skill to be able to snap field goals so that the laces of the football consistently face forward toward the goal posts when the holder catches the snap and puts the football straight down on end (so that the holder does not need to rotate the football and the kicker never sees the laces) -- "Laces Out!.

I was listening to a local sports talk radio station on my way home from work today (yes, it's Saturday), and they were interviewing a retired veteran football player whose specialty was "Long Snapper". That's the player who hikes the ball for field goals and punts. I was amazed when he said that he was one of the first long snappers who developed the skill to always snap the football so that the holder who catches the snap and puts it down for the kicker does not need to rotate the ball at all before the kick.

Apparently when he first got to the professional level, his first kicker asked him "Can you snap it so the laces are always out?" He thought he might be able to do it, and with practice he perfected the art of maintaining just 3-3.5 rotations of the football (depending on a right- or left- footed kicker) from his snap to the catch by the field goal holder.

What amazing skill, and I had no idea. I do remember that years ago it was common to see the holder routinely rotate the football as part of the field goal, and I hardly ever see that happening anymore. So apparently it has caught on as a required skill for long snappers in the NFL. I don't think I could be that consistent in my overhand throws! :smile:

Here's a blog entry describing the skill:

https://longsnapper.com/laces-out/

1642897135842.png
 
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  • #4,184
Melbourne Guy said:
TIL that the best way to paint a wood paling fence is before you nail all the palings up 🤦‍♂️

I also learned that colour selection is impossible! Tiny swatches, terrible store lighting, expensive sample pots, and marketing names that have nothing to do with reality. It's a choice nightmare :nb)
You can (effectively) get 3-in-1 from a single sample pot by going half-tint and quarter-tint (diluting with white). Don't skimp on sample pots. They're not expensive compared to the psychological cost of living with something you don't like.

Start by making medium sized samples, say 300mm square(ish). When you think you're getting close to right hue+shade, make some very large samples, 900x600 or bigger, e.g., on sheets of cardboard of whatever. If it's still not quite right, go get some more sample pots and repeat.

For the samples, if your starting board is not already white, then use a double white undercoat first, then 2-3 topcoats, to be sure you're getting a correct impression.
 
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  • #4,185
strangerep said:
You can (effectively) get 3-in-1 from a single sample pot by going half-tint and quarter-tint (diluting with white). Don't skimp on sample pots. They're not expensive compared to the psychological cost of living with something you don't like...
@strangerep, I can see now that I approached the entire fence painting project with ZERO effective planning and it's coming back to bite me. Fortunately, Melbourne's summer is finally biting this week, so I've a natural reason to regroup because it's too hot to paint much. But we've a single coat on most of the palings already, so am committed to at least completing a first coat on the rest, then the colour matching can commence in earnest. And in this case, colour is important because the fence is 13 meters long along the driveway and highly visible, so your advice is spot on 👍
 
  • #4,186
1642924908077.png
 
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  • #4,187
Melbourne Guy said:
[...] colour is important because the fence is 13 meters long along the driveway and highly visible, so your advice is spot on 👍
For exterior timber like fences (and also deck supports if visible) I reckon it's hard to go wrong with "forest green" from the colourbond range. It's a very dark grey but with a green hint, so it blends well with any surrounding vegetation. Dark colours also have a de-emphasizing visual effect -- which is probably what one wants since paling fences are not exactly the most attractive things.

Btw, that colour is also called "zeus" in the dulux range.
 
  • #4,188
strangerep said:
For exterior timber like fences (and also deck supports if visible) I reckon it's hard to go wrong with "forest green" from the colourbond range. It's a very dark grey but with a green hint, so it blends well with any surrounding vegetation. Dark colours also have a de-emphasizing visual effect -- which is probably what one wants since paling fences are not exactly the most attractive things.

Btw, that colour is also called "zeus" in the dulux range.
Disney invented "Go Away Green".

https://www.housebeautiful.com/room-decorating/colors/a3915/disney-go-away-green/
 
  • #4,189
Crabs can get scammed too. :oldfrown:

 
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  • #4,190
"most skilled typists don't know where the letters are located on the standard keyboard". [ref]

I found this out this morning after playing Wordle, and was curious why my fingers typed out a word that was phonetically correct, but spelled with the wrong letter, but was spelled correctly.
 
  • #4,191
TIL:
https://en.wikipedia.org/wiki/Harald_Bluetooth#Bluetooth_technology said:

Bluetooth technology​

The Bluetooth wireless specification design was named after the king in 1997, based on an analogy that the technology would unite devices the way Harald Bluetooth united the tribes of Denmark into a single kingdom. The Bluetooth logo
25px-Bluetooth_FM_Color.png
consists of a Younger Futhark bind rune for his initials, H () and B ().

bluetooth.jpg
 
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  • #4,192
Today I learned that professional pillow fighting is a thing.

 
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  • #4,193
TIL that the 21st century began on January 1st, 2001.

Like a stupid programmer, I instinctively thought It began on January 1st, 2000.

I never realized the year zero doesn't exist.
 
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  • #4,194
You can modulate from C major to B# major, but would not recommend trying this at home
Capture.gif
 
  • #4,195
jack action said:
I never realized the year zero doesn't exist.
I tried telling people that in 2000, but soon gave up. Is there an official definition of 21st century anywhere?
Wikipedia says there are two viewpoints :
Screenshot from 2022-02-03 20-18-23.png
 
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  • #4,196
Keith_McClary said:
I tried telling people that in 2000, but soon gave up. Is there an official definition of 21st century anywhere?
Wikipedia says there are two viewpoints :
View attachment 296521
There's a lot more info on the page Year Zero.

Not having a year zero might create a problem mathematically when doing calculations across BC and AD, but really what does "Year 0" mean? Zero is supposed the be a single transition point, not an elapsed time.

Even if we want to use a Year Zero, it would be more logical mathematically to use a 0 BC and a 0 AD. This way the date would represent "the number of years since" and the month and day would be the decimal part. But that would be confusing to everyone now as we would have to subtract 1 year from the years on the Gregorian calendar.
 
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  • #4,197
BWV said:
You can modulate from C major to B# major, [...]
It's been a long time since I formally learned music, but I thought that B# is the same thing as C (at least, on a normal piano keyboard)? :oldconfused:
 
  • #4,198
strangerep said:
It's been a long time since I formally learned music, but I thought that B# is the same thing as C (at least, on a normal piano keyboard)? :oldconfused:
Yes, C and B# are the same note on a piano, but theoretically not the same. In the key of C#, for example, B# is the correct notation for that pitch. But the key of B# is silly, even though the modulation I posted came from a book by Max Reger, who was a great turn-of-the century composer
 
  • #4,199
Greg Bernhardt said:
Today I learned that "chasing the dragon" is slang for smoking heroin.
It refers to chasing the initial high off of many drugs. Unfortunately that initial high "feel" is no longer obtainable. One can certainly spiral into addiction chasing it.
 
  • #4,200
TIL:

1936 - the term “volkswagen” was used on entry level cars from different companies before it became the Volkswagen we know from the KdF car.

ford-volkswagen.jpg
 
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