iMechanica - AM 105a - Comments

LAB/Office Whiteboard

Fattaneh Morshedsolouk — Thu, 06 Nov 2008 11:39:36 -0500

from http://www.phdcomics.com

More tongue in cheek humor

MichelleLOyen — Tue, 13 May 2008 11:06:57 -0400

from http://graphjam.com/

a funny but useful graph ...

Andrew Norris — Wed, 30 Jan 2008 09:57:46 -0500

Nice one! And here is a great graphic that I love to show people

Use it in your talk to show the perils of correlating data!

Presentation skills joke

MichelleLOyen — Wed, 30 Jan 2008 04:40:20 -0500

Hopefully most iMech'ers wouldn't resort to this!

(from xkcd )

real life is sometimes funniest

Andrew Norris — Fri, 28 Dec 2007 11:56:07 -0500

There is a funny story about the theoretical physicist and mathematician Theodor Kaluza, of Kaluza-Klein fame. It is usually argued that any new theory must be confirmed by experiment. But some theoreticians have the opposite opinion - that experiments are meaningless unless backed up by good theory. Kaluza was definitely in the second camp. He was also a non-swimmer, but in order to prove his point about the power of theoretical knowledge, he claimed that he could learn to swim from reading a book. So in his thirties he read up on swimming, and one day without any lessons, he jumped in the deep end and sure enough started swimming.

I thought the story so hilarious that I had to check it out - and it is true . I came across the Kaluza anecdote in the book "Faster than the speed of light" (2003) written by a young theoretical physicist - Joao Magueijo - who proposed an alternative theory to the "accepted" model of cosmology. The book is about his struggles to have his theory gain acceptance in the theoretical physics community. Along the way he offers many anecdotes and sharp comments on scientific research. A great read.

Sidney Harris Miracle Step!

Dhruv Bhate — Thu, 27 Dec 2007 17:44:58 -0500

Doesn't this seem to happen all the time?

More at http://www.sciencecartoonsplus.com

Tacoma Bridge Failure was Due to Flutter

Madhukar Vable — Sun, 23 Dec 2007 04:43:07 -0500

Hope I do this right as I am new to this.

I believe the failure of
Tacoma Bridge was not due to resonance but due to
aerodynamic instability of flutter. [See Billah K.Y. and Scalan R.H. (1991) "Resonance, Tacoma Narrows Bridge Failure and Undergraduate Physics Textbooks" Am. J. Phys. Vol 59, No. 2, pp 118-124).

Flutter occurs when the
bending and torsion modes couple. In this coupled mode the
deformation causes the aerodynamic loads to increase which in turn
causes additional deformation and the cycle grows till the stucture
breaks. Today wind tunnel testing of suspension bridges is mandatory
but was not understood in bridge design at the time Tacoma Bridge was
built.

Madhu

The Imposter

David M. Cooper — Thu, 20 Dec 2007 19:02:57 -0500

I call this function "The Imposter". It is a close fit to y=sin(x), save for the derivative at y=0. Do not be fooled.

Nachiket, thanks for the heads up on the four-dimensional dog. I'm sure it has eaten homework in just about every neighborhood.

Multiphysics (CFD + Structural) Software for Bridge Dynamics

Ondrej Kalny — Fri, 14 Dec 2007 01:12:06 -0500

In September, I attended IABSE (International Association for Bridge and Structural Engineering) symposium in Germany. It was interesting to see several presentations dealing with advances in computational modeling of bridge dynamics. These programs combine CFD with structural models and are becoming so powerful that can virtually eliminate wind tunnel testing, at least during the conceptual design stages.

ok, BridgeArt.net

useful website for mobius transforms

Zhigang Suo — Tue, 11 Dec 2007 20:38:07 -0500

A message from Meghan Purdy:

Hi Professor Suo,

I just found this very useful website. It lets you apply any Mobius transform to a lot of shapes on the z-plane, and it's really useful for checking answers on this homework. You may want to pass this on to the other students.

http://www.math.ucla.edu/~tao/java/Mobius.html

Best,
Meghan Purdy

Tacoma Narrows leads to the "Windbelt"

Mark E. Walter — Mon, 10 Dec 2007 13:06:31 -0500

A young inventor says that the Tacoma Narrows Bridge inspired him to invent the "Windbelt" to generate electricity.

http://www.humdingerwind.com/windbelt.html

Mobius transformation

Biswajit Banerjee — Mon, 10 Dec 2007 10:12:44 -0500

Just wanted to point out an earlier thread on the topic at http://imechanica.org/node/1619

Some more

Arun Prakash — Mon, 05 Nov 2007 10:52:48 -0500

A couple more, which are "common" knowledge in the scientific world

1. Theory is you know something and it does not work. In practice something works and you don't know why. Programming combines both theory and practice, something doesn't work and you don't know why.

2. Simulation is something and except you as the simulator, nobody else believes. Experiment is something that except you everyone else believes.

some more jokes

Nachiket Gokhale — Mon, 05 Nov 2007 10:38:01 -0500

A long time ago, I came across this set of jokes of mathematics. Enjoy.