Charles V: French scientists decode 500-year-old letter
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"The first thing was to categorise the symbols, and to look for patterns. But it wasn't simply a case of one symbol representing one letter - it was much more complex," says Pierrot.
"Simply putting it into a computer and telling the computer to work it out would literally have taken longer than the history of the universe!"

The part about if they had just put it into a computer it would have taken longer than the history of the universe is really misleading tripe. While technically true, it is without meaning.

Consider a simple monoalphabetic cipher in which each letter of the plaintext alphabet is replaced by a single, unique symbol in the ciphertext alphabet. For a 26-character alphabet like English, the number of possible mapping is 26! or right at 4x10^26. If a computer could completely evaluate one billion of those possibilities every second, it would take nearly 13 billion years to evaluate all of them (or roughly the age of the universe).

Yet kids break such ciphers as part of the Sunday newspaper every weekend (though they have some help because spaces between words are always included).

But back in the mid-1500's when this letter was written, such ciphers were common place and how to break them had been well-developed by the Arabs a couple centuries earlier. So the code makers developed tricks to make it harder for the code breakers, including using multiple symbols to represent the same letter (this was the primary means of defeating frequency analysis), using nulls (symbols that had no meaning whatsoever) and symbols that represented letter combinations, entire words, or concepts. This letter appears merely to be representative of the state of the art at the time and contemporary code breakers likely could have deciphered it had it fallen into their hands and had they decided it was important enough to make the effort.

At about this same time (~30 years later), such a letter was intercepted and was decoded and was singularly responsible for Mary Queen of Scots losing her head.

Interesting, at about this same time the Vigenere cipher, which is polyalphabetic, was invented and was considered by most to be unbreakable -- and it did withstand all efforts to break it for about three centuries. Today, breaking such a cipher is a common first homework assignment in a cryptography course.

 

Using the: https://pages.mtu.edu/~shene/NSF-4/Tutorial/VIG/Vig-IOC.html

 

 

When art, computers, CNC, 3D printing, and robotics come together for an amazing conversation piece.

https://www.kickstarter.com/projects/1199521315/sisyphus-the-kinetic-art-table

 

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Did you hear about the clever solution that Dutch bike company VanMoof came up with to protect their products during shipping?

They redesigned their packaging to look like a TV box, and it's been hugely successful in reducing damages! Their delivery damage rate has dropped by a whopping 80% since implementing this strategy.

Talk about thinking outside the box!

 

Freekin' AAaaay!
https://www.youtube.com/shorts/o9M8UwrSQpg

 

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Did you hear about the clever solution that Dutch bike company VanMoof came up with to protect their products during shipping?

They redesigned their packaging to look like a TV box, and it's been hugely successful in reducing damages! Their delivery damage rate has dropped by a whopping 80% since implementing this strategy.

Talk about thinking outside the box!

Great idea as you want the product fresh and undamaged on delivery.

 

 

I've said it before, and I'll say it again, this place needs a double like button!

 

I've said it before, and I'll say it again, this place needs a double like button!

I almost want to create a second account and click like again. But - - - .

At the end of the video - 17:19 the guy leaves the second floor using a pneumatic piston to safely and slowly lower him to the ground. Then when released, gravity resets it. Awesome fire escape mechanism. Don't know if anyone else saw or thought that.

 

https://www.youtube.com/shorts/1Qvd9rBbCMg

 

STATIC DISCHARGE IDEAS?

Yesterday I was cutting PVC into 3/32" by 3/4" strips from a PVC plank 8' by 4" x 3/4". Cutting on the band saw because the blade is so much thinner, narrow saw kerf as opposed to the tablesaw kerf of about 0.080". After which I did my cleanup. Man there was a lot of cleanup to be done. Grabbed the shop vac hose and began cleaning around and inside the band saw. Made the mistake of touching the frame of the saw after doing a lot of vacuuming. DANG! that hurt. A MASSIVE static discharge occurred. Felt like I got punched in the arm. Hard!

So it would be cool if anyone could offer tips or tricks to reduce or eliminate static buildup in the plastic hose. I get similar shocks when vacuuming wood sawdust. It would probably be a good idea to incorporate static dissipative applications into my rigid dust collection as well.

OK, woodshop question but still in the realm of electronics because of the buildup of static energy.

 

STATIC DISCHARGE IDEAS?

Yesterday I was cutting PVC into 3/32" by 3/4" strips from a PVC plank 8' by 4" x 3/4". Cutting on the band saw because the blade is so much thinner, narrow saw kerf as opposed to the tablesaw kerf of about 0.080". After which I did my cleanup. Man there was a lot of cleanup to be done. Grabbed the shop vac hose and began cleaning around and inside the band saw. Made the mistake of touching the frame of the saw after doing a lot of vacuuming. DANG! that hurt. A MASSIVE static discharge occurred. Felt like I got punched in the arm. Hard!

So it would be cool if anyone could offer tips or tricks to reduce or eliminate static buildup in the plastic hose. I get similar shocks when vacuuming wood sawdust. It would probably be a good idea to incorporate static dissipative applications into my rigid dust collection as well.

OK, woodshop question but still in the realm of electronics because of the buildup of static energy.

At work to minimize ESD we make sure to keep humidity between 30-60% and the temperature between 70 and 85 F (both are actually part of our official ESD procedure). Working on a metal surface that's grounded also really helps (or, at least, having some way to ground the plastic hose, even if it's a metal band connected to a grounded metal surface like the ESD bands). We also have static-dissipative boots we're supposed to wear, but I rarely see anyone in my lab actually use them (the other labs in the building, where the guys are working with much, much higher power, I'm pretty sure it's strongly enforced).

 

At work to minimize ESD we make sure to keep humidity between 30-60%

Northern Utah, I'd have to add humidification for that level. Not unusual for humidity to be around 5%.

We also have static-dissipative boots

Not effective on non-conducting flooring. My woodshop has linoleum flooring.

Working on a metal surface that's grounded also really helps

Though you don't have to touch something grounded, an ESD can happen. Such as when you grab the doorknob on a wooden door - you can still get a heck of a snap. The frame of my bandsaw is definitely grounded. After that initial shock I started keeping my hand on the frame while vacuuming.

What I'm looking for is some way to ground the plastic hose. Since plastic doesn't conduct - putting a length of wire either on the outside or the inside might help, but then it has to be grounded somewhere. That's doable but a bit of a pain since the hose feeds into a dust separator before it goes into the plastic body of the vacuum. Even though the motor and electrical's inside are grounded, it does nothing for the plastic parts. The separator is plastic and the bucket it empties into is also plastic.

Curious to see if anyone has a practical approach. The hose is ribbed but is not spiral in nature. Each rib forms a complete single circle. It's not like a screw thread where I could potentially wrap a small gauge steel wire the length of the hose, which is 1 1/4" diameter and 10' long. Just guessing but there's probably about two or three wraps per inch. So that would be a whole lot of wire. Using three wraps per inch I'm getting over 1400 inches of wire. (117' + ). A much shorter route would be to run the wire on the inside but then it could interfere with larger chips of wood getting stuck in the narrow passageway.

 

In my print shop during the winter and on those particularly bad days I used to carry a spoon around with me and touch a grounded object after walking across the floor and doing other buildup activities.

 

Winter blues!
Spray all your plastic with that blue window cleaner.

 

In my print shop during the winter and on those particularly bad days I used to carry a spoon around with me and touch a grounded object after walking across the floor and doing other buildup activities.

Carrying a spoon with you is not not necessary. For me, it's enough to touch a grounded object with my knuckles to make sure that the experience of electrostatic discharge is a painless one.

 

Almost 100kM/h speed skater1
https://www.youtube.com/shorts/Lf3Dy1w9Clg

 

Dewalt and Milwaukee come to the aid of when you feel horny.
https://www.youtube.com/shorts/3gcSo0cJu7E