Search found 613 matches

by pezman
Fri Feb 08, 2008 1:40 am
Forum: Tools and Construction
Topic: Online SAGE notebook
Replies: 2
Views: 1735

calculate the sag of a SS W-beam

Prettied up, with type-set equations
by pezman
Thu Feb 07, 2008 6:07 pm
Forum: Tools and Construction
Topic: FDEs
Replies: 45
Views: 2808271

Beam sag agreement

I agree that you were correct in the first place and that my "correction" was incorrect -- hence my posting of the "Litella" function. Time permitting, I'll try to maintain a separate, parallel thread that builds a SAGE notebook illustrating your presentation. Fun for me, maybe instructive for other...
by pezman
Wed Feb 06, 2008 5:44 pm
Forum: Tools and Construction
Topic: FDEs
Replies: 45
Views: 2808271

the Litella function

... umm ...
by pezman
Wed Feb 06, 2008 5:35 pm
Forum: Tools and Construction
Topic: FDEs
Replies: 45
Views: 2808271

calculate the sag of a SS W-beam

Hi Forrest, It's literally been decades since I have had to do calculus, but I suspect that the M term that you provide is not quite right for a beam supported at both ends -- I would expect it to be symmetrical about l/2. If this observation is correct, I have to confess that I only found this by b...
by pezman
Fri Feb 01, 2008 10:04 pm
Forum: Tools and Construction
Topic: Online SAGE notebook
Replies: 2
Views: 1735

Online SAGE notebook

SAGE is a free software project that has some of the capabilities of tools like Maple, Matlab, Mathematica MathCAD etc. There's an online notebook that you can use freely in order to share stuff: https://www.sagenb.org/pub/ I also downloaded the Windows VM, which can be found here: http://modular.ma...
by pezman
Wed Dec 12, 2007 9:07 pm
Forum: Tools and Construction
Topic: Odd Metal jars
Replies: 554
Views: 1748759

UFlow modeling of Jam Jars

You can actually model jam jars or other Reynstian devices by making a symmetrical structure, e.g. something like the following, bad, not-quite-symmetrical ASCII art: __/''''''''''''\__ __ ........... __ ..... \......../ Basically, the mid-point of the structure is the "bottom" of the jar. The symme...
by pezman
Wed Dec 12, 2007 5:10 pm
Forum: Tools and Construction
Topic: Odds and ends
Replies: 1715
Views: 319423

Möbius Dictus!

Dang, it seems that this may have already been done ... http://www.flickr.com/photos/steve_schmeiser/1662319474/ In fact, squash training seems to be quite the niche hobby ... It also seems that there is no shortage of folks in-klein-ed to tinker with topological oddities ... http://www.flickr.com/p...
by pezman
Tue Dec 11, 2007 10:10 pm
Forum: Tools and Construction
Topic: Odds and ends
Replies: 1715
Views: 319423

Klein gourd

What if you took a long-neck squash, cut a hole in it and then threaded the stem through and coaxed it into growing into a klein-ish gourd ... per the attached, very-bad picture.
by pezman
Wed Nov 28, 2007 5:56 pm
Forum: Tools and Construction
Topic: Odds and ends
Replies: 1715
Views: 319423

Method for the production of laser-active quartz glass

Wow, that is a great patent -- Claim 15 is the big money-maker: 15. The method according to claim 1, wherein characterized in that a bulk body with a radially inhomogeneous refractive index distribution is formed from SiO.sub.2 granules of different refractive index, and the bulk body is sintered or...
by pezman
Tue Nov 13, 2007 9:59 pm
Forum: Ramjet forum
Topic: air requirements for a large subsonic ramjet
Replies: 8
Views: 5846

Flying 4-runner

A hovercraft prop might be better than a conventional prop. They are designed for ducted operation and an unplanned flight is far less likely.

e.g.: http://www.hoverhawk.com/
by pezman
Sat Nov 10, 2007 6:57 pm
Forum: Off topic forum
Topic: Toys R Us Super Computer
Replies: 4
Views: 2232

More PS3 stuff

Haven't had as much time as I'd like to fiddle with this, but I have loaded and executed an interactive Ray Tracer program (http://www.alphaworks.ibm.com/tech/irt) and I installed and built CorePy (http://www.corepy.org/), which is an augmented version of Python that allows one to write native assem...
by pezman
Wed Oct 31, 2007 10:54 pm
Forum: Tools and Construction
Topic: Odd Metal jars
Replies: 554
Views: 1748759

Little jackie paper loved that rascal puff

Is there some coded sub-text here suggesting some altogether-different-unspoken-alternative-purpose-but-still-metaphorically-involving-flying kind of jam-jar?

A pj-powered dirigible would be cool. Using the considerable other-wise-wasted(?)-heat as a way to loft your balloon is very clever indeed.
by pezman
Mon Oct 29, 2007 2:05 am
Forum: Off topic forum
Topic: Toys R Us Super Computer
Replies: 4
Views: 2232

PS3 "butchery"

Actually, it's a PS3, and it is designed to allow a dual-boot.

Very cheap for a super-computer (like $0.20 per gflop)