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Comment Re:One hand, 12 o'clock ... (Score 4, Informative) 756

I was in an airbag-deploying accident about a year ago, and ended up with some pretty good bruises / rashes on my arms. I think I was at 10 and 2, roughly.

In the "ideal" case where you hit something and your hands remain at the 9 and 3 positions, this would be great. But I'm willing to wager that for most accidents, there is at least 0.2 seconds of [unprintable], in which case you will try to swerve out of the way. In this case, as was the case for me, your hands and arms will inevitably be right in front of the airbag, since you're twisting the wheel in an effort to go around whatever it is in front of you. The airbag goes off and your arms get pinned between the airbag and your chest ... or worse.

So, I applaud the intent to keep your arms and hands out of the way with the 9 and 3 o'clock positions, but I just don't think it will do any good in most real-world situations.

Comment Re:Good luck (Score 1) 148

I call BS.

To the uninitiated, I agree it sounds bad. "OMGWTFBBQ we're putting NUKES in SPACE!!1!"

But it's not actually that bad. The fact is, uranium is not that radioactive before it has been in a nuclear reactor. I have held kilogram-quantities of uranium in my hands -- and still have all 10 fingers to show for it. Plutonium is more radioactive -- half a kilogram is warm to the touch -- but it's not deadly as long as it stays external to your system.

The nastiness starts coming in after the reactor goes critical and fission products have a chance to build up. But you'd only let the reactor go critical AFTER the thing has left LEO.

Having designed a space reactor before, I know that it's quite possible to even to criticality measurements on the reactor (i.e., zero power measurements) before you launch it and still call the reactor "clean."

For some real fun-and-games, check out the re-entry of the Soviet TOPAZ reactor (Cosmos-954) over Northern Canada in the late 1970's.

Comment Re:why isn't thorium being developed? (Score 5, Informative) 299

Thorium isn't being developed in the US for 2 reasons:

1. Current uranium-based reactors are more affordable than thorium reactors.

2. The path for licensing a thorium-based reactor in the US is exceedingly uncertain.

While a thorium-based fuel cycle may be a good idea, it's just not going to be done by any commercial enterprise today. The costs and risks are too high. When staring at a $5B initial investment cost, any electrical utility is going to favor the known route ... which, frankly, could just as easily mean building 10 natural-gas fired plants instead of 1 big nuke.

India, however, is going full-bore on a thorium-based fuel cycle, and has already built a few reactors that are capable of accepting thorium. Copied shamelessly from world-nuclear.org:

India's plans for thorium cycle

With huge resources of easily-accessible thorium and relatively little uranium, India has made utilization of thorium for large-scale energy production a major goal in its nuclear power programme, utilising a three-stage concept:

Pressurised heavy water reactors (PHWRs) fuelled by natural uranium, plus light water reactors, producing plutonium.

Fast breeder reactors (FBRs) using plutonium-based fuel to breed U-233 from thorium. The blanket around the core will have uranium as well as thorium, so that further plutonium (particularly Pu-239) is produced as well as the U-233. Advanced heavy water reactors (AHWRs) burn the U-233 and this plutonium with thorium, getting about 75% of their power from the thorium. The used fuel will then be reprocessed to recover fissile materials for recycling.

This Indian programme has moved from aiming to be sustained simply with thorium to one 'driven' with the addition of further fissile plutonium from the FBR fleet, to give greater efficiency. In 2009, despite the relaxation of trade restrictions on uranium, India reaffirmed its intention to proceed with developing the thorium cycle.

A 500 MWe prototype FBR under construction in Kalpakkam is designed to produce plutonium to enable AHWRs to breed U-233 from thorium. India is focusing and prioritizing the construction and commissioning of its sodium-cooled fast reactor fleet in which it will breed the required plutonium. This will take another 15 â" 20 years and so it will still be some time before India is using thorium energy to a significant extent.

Comment Re:Hard to believe (Score 1) 845

There's a very important aspect to bring up that has not been mentioned in the comments:

THE EXAMPLES PROVIDED IN THE LINK ARE FOR THE 4TH AND 8TH GRADE LEVEL TESTS. The article discusses how the school board member couldn't pass the tests for the 10th grade level.

So, unfortunately, we're not given samples of the types of questions that the school board member flubbed so badly. While I'm likely to agree with him -- even as an engineer I have used perhaps 5% of the math I've learned -- I would prefer to come to that judgement on my own.

Comment Re:Heard about Marathon (Score 2) 105

++ on the decent plot and story. There was just something engaging about those Durandal / Tycho battles, and you, the small pawn between them with double shotguns.

That, and playing at night with headphones ... the audio could really set your hair tingling.

I used to drive the mac computer lab managers nuts by secretly installing Marathon Infinity on all the macs, then making the folder invisible so they couldn't (easily) delete it. Good times, indeed.

Oh, and grenade hopping FTW.

Comment Re:"Free" money (Score 1) 1797

The cost of education has risen about twice as fast as inflation over the past 10 years ... and so have government subsidies.

Even in 2009, President Obama set college tuition hikes in his sights. Alas, he didn't (hasn't) follow(ed) through.

I hope Ron Paul's suggestion re-ignites the debate to bring down tuition, and quit having the government pay for it.

Comment Balancing work, family, and play (Score 1) 148

I was impressed and somewhat humbled by all the different activities you had featured on your website. Do you ever sleep?

In all seriousness, how do you (appropriately) balance work, family, and play time? In looking at your website, you seem to do at least two of those (family + play time) very well.

Comment Re:split zoning (Score 1) 514

Agreed. Even at home, my mantra is, "Minimize turns."

Do 1 or 2 laps around the outer edge to give you a buffer so you don't spray grass all over the sidewalks, etc., and then choose the longest dimension of the ~rectangular shape you have left. Make long passes back and forth along this edge, alternating left, right, left, right. (If you're not bagging, this means you will run over some of your discharge sometimes, but that's OK as long as the grass isn't too tall.)

Using this method reduced the time necessary to mow my 1/3 acre by about 10%. Fairly handy.

Comment Re:We have these already, and they have a function (Score 1) 130

Well said.

The only other comment I would make is that the government has made a stark change away from hard, technically inclined people to "soft," general-management types ... and by so doing, has lots its ability to properly manage the projects it seeks to execute.

Stories like yours above, where the DoD was paying 4x your salary for the services of one, are examples of where some government PM didn't know better. I suppose it's also possible that you were working on some super-classified system, for which the pay scale increases significantly.

I actually pine for the days when 50% of all government GS-15's have to have been prior contractors. Who better to manage the work than someone who has done it before? It has been spun as a bad thing in the press ("Oh Noes! Government official sends money to his prior employer!"), but in my experience, that happens because the government PM is experienced, knows what he or she wants, and the PM usually wrings out a good deal for the government in the process.

Take, for example, the program management of the F-35 fighter aircraft. The person in charge of managing a $300 BILLION weapon system had better have some serious acquisition chops.

Comment Re:This could work (Score 5, Insightful) 210

OK, Praise #1: This guy is awesome. He has the chops and wherewithal to build his own Farnsworth fusor by age 14.

Praise #2: He's not satisfied with just building the thing, he wants to apply the thing. That's what I find truly commendable.

So he goes off and learns a lot of good science and engineering in how to look for special nuclear material. Dennis Slaughter, of Lawrence Livermore National Lab, was featured on the front page of the American Nuclear Society's Nuclear News magazine in November of 2007 for his "nuclear car wash." Basically the same idea: use a neutron generator (a big one, in this case) and look for signatures of delayed neutrons in response.

So, what Taylor has done isn't revolutionary, but I'm sure it's a lot cheaper than any other neutron active interrogation system out there. Good for him. And, again, awesome job for hunting for useful applications of technology.

Comment Re:well... (Score 1) 561

Apple tried this ten years ago. It was called KidSafe. Unfortunately, they had to drop it due to low usage. The deal there was it was a large collection of whitelisted sites ... and some poor Apple employee had the job of going out and whitelisting sites as they came up.

Searching for "Apple Kidsafe" brings up a few more recent widgets that appear to do something similar.

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