The Internet of ME: math

Showing posts with label math. Show all posts

Tuesday, March 8, 2016

psychoacoustictendencies: Get out. I am angry at how funny I...

psychoacoustictendencies:

Get out.

I am angry at how funny I find this.

via Tumblr http://bit.ly/1XaNKZ3

Monday, March 7, 2016

fuckyeahmathandsciencetattoos: It is a design by SymbolGrafix....

fuckyeahmathandsciencetattoos:

It is a design by SymbolGrafix. The tattoo artist is Masato Kaisawa from Mexico City.
I did it at 03/14/15 special Pi day, to pay my respects to mathematics as a symbol of unity, curiosity and the pursue of knowledge.
Also, I am a physics engineer and this is my bachelors degree medal :)

That’s dedication.

via Tumblr http://bit.ly/1R1gmzt

Thursday, March 3, 2016

engineerthougts: Unfortunately brain doesn’t like maths. 😪 Me.

engineerthougts:

Unfortunately brain doesn’t like maths. 😪

Me.

via Tumblr http://bit.ly/1oTnDdY

Sunday, February 28, 2016

thebeakerblog: Imagine you have a big bucket. And in that...

thebeakerblog:

Imagine you have a big bucket. And in that bucket you pack a bunch of soft, slightly-squishy tennis balls. For the sake of argument, we’ll say you threw in 128 of the little green spheres.

Still with me? Good. Now, imagine all the different ways you could arrange those balls within the bucket. If you think the number is near-infinite (in the non-literal sense) you’d be right. But that’s the key, it’s near infinite. With a powerful enough computer (or a lot of time), it’s conceivable you could count all possible configurations of those 128 balls.

Now, research published in the journal Physical Review E, claims to have done just that. It says 128 balls could be arranged 10^250 different ways – ten unquadragintilliard, a number bigger than our current estimate for the number of particles in the universe.

OK. So that’s cool. We found a really big number, but stick with me for a minute and let your imagination go nuts.

If you think about it, this calculation actually could open the door to some really amazing future knowledge. Presumably, with a powerful enough computer, one day we might be able to calculate all possible configurations of any granular system. Say, sand grains in a desert, or snow flakes on a mountain. If you think about it, one day, with enough raw computing power, could it be possible to predict sand dune formation? Or know, precisely, how an avalanche will move down a mountain?

Read more: Physical Review E: Turning intractable counting into sampling: Computing the configurational entropy of three-dimensional jammed packings

(Image Credit: Creative Commons, PughPugh)

I don’t understand the application of this, but cool, we did a thing and big numbers.

via Tumblr http://bit.ly/1piIKqB

Wednesday, February 17, 2016

How would you recommend to study for math college final?

Hello! When I study for math exams, I almost exclusively rely on past exams provided by the instructor. It’s the best way to figure out what to expect and what areas you need to brush up on. Alternatively, if you don’t have past exams to look at, doing practice problems from your textbook is another good method. I have some posts in my math tag that may also interest you!

via Tumblr http://bit.ly/1oLg0Xq

Tuesday, February 16, 2016

engineeringtldr: engineering-girls: engineeringtldr: We need...

engineeringtldr:

engineering-girls:

engineeringtldr:

We need to design a bracket to take some kind of repeated bending load. One end is clamped stationary between a couple of plates, and a uniaxial, fully-reversed load with a maximum of 300 lbf rides on the end at a distance of a away from where it’s clamped. There’s a fillet where it clamps into the wall to try and keep it from fretting on a sharp corner. We’ll say it’s machined steel with an ultimate tensile strength of 82000 psi and an elastic modulus of 28 x 10^6 psi. We need it to survive basically forever. We aren’t given any dimensions, so we need to figure out exactly what this part has to look like. (Problem adapted from Machine Design: An Integrated Approach, 4th Ed., by Robert L. Norton.)

This is a pretty complicated problem - although we’re given a basic shape, we need to design this piece more or less from scratch. Here’s the basic process we’ll follow for this and other fatigue design problems:

Initial estimated design

Calculate nominal stresses

Apply fatigue stress concentration factor

Calculate principal stresses

Calculate corrected endurance limit or fatigue strength

Calculate safety factor

Modify design

This gets long and ugly, but none of the individual pieces are too bad.

Keep reading

The cool thing is being able to write code (either in a spreadsheet or another program like octave/matlab) to solve the problem by iterations for you.

YES. A thousand times yes. If you have access to a spreadsheet or similar, by all means, do out the math, plug in your numbers, and let the program do the heavy lifting for the iterations.