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Comment Re:Go big or lose your wall (Score 1) 388

Precisely! If I were the company demonstrating the mesh, I'd put it on the front side as well-- at least that way they would get a confinement effect and the wall wouldn't be as traumatized. Those bricks have no gravity capacity in the state they are shown, even though the mesh on the back is preventing them from falling.

This kind of material have been used in seismic retrofit for years, and if you, the audience, have enough idle time for a long story, you can read on to see why. For a long time, up until the 1994 Northridge earthquake, concrete columns in the US that were not part of a lateral force resisting system were designed to have just enough vertical and horizontal spiral steel (usually none at the beam-column joints) to resist their respective gravity demands. Look up 1994 Cal State Northridge Parking Garage on Google, and you'll see what happened to buildings with this kind of design.

What happens is when a building moves laterally, the columns have to move to even if they aren't designed to dissipate the forces resuting from the building's lateral movement. Without the horizontal steel, the columns are not adequately "confined." When concrete is compressed, just like any other material, it wants to expand outward (not a desirable option with a brittle solid like concrete). Confinement resists these expansive forces and thus increases the compressive capacity of the concrete. When the structure above or below moves laterally, the column bends, and bending puts part of the column in compression and another in tension. Concrete has negligible tensile capacity, so the vertical steel is used to resist the tensile stress. Without confinement, the column's compressive capacity is lower than the tensile capacity of the steel. Concrete is brittle, and thus fractures, losing all of its strength. This is what happened to the Cal State Northridge Parking Structure; with the gravity system destroyed, the decks collapsed, and the walls fell inward with no diaphragm to support them. Had the columns adequate confinement, the column's compressive capacity would have exceeded its tensile capacity. Steel is ductile, and thus will elongate instead of fracturing, which will only occur at a much higher demand. Even with the steel straining, the column moving back and forth, and the thin layer of surface concrete spalling off, the confined portion of concrete within the steel stays intact, thus preserving the gravity system well enough to prevent collapse.

Current design codes, inspired by the garage collapse as well as others throughout Los Angeles as a result of this event, require a certain amount of confining steel over the entire length of the column. With existing structures, this is not an option. Thin composite jackets, probably the same material as the product from the article, have been shown to be extremely effective when wrapped around unsatisfactory columns in providing confinement.

Comment Re:Funding (Score 1) 136

Games aren't the only applications that would benefit from what OnLive is researching and developing; as such, I imagine Autodesk is very interested in this kind of infrastructure. AutoCAD and Revit both demand a lot of computer resources, and since the licenses for these programs are relatively expensive, fronting both the cash for licenses and the high-end computers to run the programs may be prohibitive for some companies.

Comment Re:Congratulations! (Score 1) 432

To parrot a tidbit I picked up off of Wikipedia and to reinforce the parent's point:

While the value of Ï has been computed to more than a trillion (10^12) digits, elementary applications, such as calculating the circumference of a circle, will rarely require more than a dozen decimal places. For example, a value truncated to 11 decimal places is accurate enough to calculate the circumference of a circle the size of the earth with a precision of a millimeter, and one truncated to 39 decimal places is sufficient to compute the circumference of any circle that fits in the observable universe to a precision comparable to the size of a hydrogen atom.

From with footnote markers removed.

Comment Re:Technically.. (Score 1) 362

For the sake of argument, suppose that the method employed by the student to cover the distance in a short amount of time was itself illegal (surpassing posted speed limits). The student has himself on tape breaking said speed limits. Are contracts that implicitly prescribe illegal actions such as the contract in question enforceable? Even if not implicitly prescribed, could the student's fulfillment of the contract be voided since he broke the speed limit to do so?

What this may look like is me trying to get free legal advice. It is actually my curiosity lazily attempting to sate itself.

Comment Re:Sources of Ethanol (Score 3, Interesting) 176

I was listening to NPR's All Things Considered yesterday (7/15/09) and they had a profile on a California start-up developing algae-sourced fuel in partnership with Exxon-Mobil.

Oil companies aren't stupid. They invest heavily in all of the R&D for these alternative sources of fuel so they can oligopolize it when any of the research produces something practical.

Comment Re:Bruce Perens is a censor! (Score 1) 324

The government is accountable to the people, but only insofar as the Constitution allows. What I say is beside the point that the coloring book was a pretty bad idea.

Is it censorship? I don't know, and I don't care if it is in this particular case. I just know that the book was available on FEMA's site for SIX YEARS. I wonder how many kids' minds it put at ease in that time.

Comment Facebook is going into television (Score 1) 409

Recent events have led me to believe that the ToS was changed because Facebook is beginning to delve into TV promotion. I think it was during the NBA All-Star Game that I saw a Facebook plug in one of the overlays that came up. If they are going to be putting up any user-generated content in their ads (which to me seems wholly unnecessary), they'll need to cover their backs by claiming free use of all submitted content as a term of service.

Of course very few if any people like the idea that they can't opt out of being data mined and sub-licensed once they've signed up, and thus the backlash.

Comment Re:California Strikes Again (Score 5, Insightful) 481

The article summary mentions building codes, which is an industry standard. I have knowledge of building codes being a structural engineer so I use them as an example to help frame my arguments.

The 2007 California Building Code is not copyrighted. However, it draws almost exclusively from the International Building Code (IBC), which is copyrighted and published by the International Code Council (ICC). ICC is a non-profit organization dedicated to the development of model building codes as well as the testing and approval of construction products. The ICC has no financial interest in what it does (in principle), and makes legitimate use of copyright to continue its work.

Should government should be allowed to adopt and enforce copyrighted works as law? If so, who should be responsible for the costs of distributing the law to the citizens? I do not believe that a work should lose the property of being copyrighted when entered into the law; however, it could easily be argued as legally allowable under the guise of eminent domain. The state, and thus its citizens, should realize the fact that adopting copyrighted material as law requires them paying for it. The ICC and all other organizations that develop industry standards should reevaluate whether it is ethical and/or reasonable to create and copyright material which is intended to be adopted into law.

In the end, it is what Weaselmancer brought up in a sibling post: a "broken business model." I believe the state should budget and pay the code councils to do the work and get it distributed rather than indirectly and unequally tax their constituency by making them pay for the published materials (I disclose that I am one of those being disproportionately taxed).

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