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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.

Comment Re:Nuke power (Score 4, Interesting) 483

I'm really not trying to get into a debate on semantics, but releasing a few TBq of radiation counts as "significant" in my mind. At the very least, it's way more than background.

This article by some nuclear engineers at NC State is an excellent, fact-based breakdown of what the effects are of the Fukushima accident, with known numbers to date.

Bottom line: Three cancers.

Three cases of cancer that would not otherwise have occurred, and this is using the (very conservative) linear-no-threshold assumption.

Others in this thread have been bleating about how bad nuclear power accidents have been. The following quote from the UN's final report on the Chernobyl accident (a summary can be found here ) doesn't support their claims:

"Apart from the increase in thyroid cancer after childhood exposure, no increases in overall cancer incidence or mortality have been observed that could be attributed to ionizing radiation. The risk of leukemia, one of the main concerns (leukemia is the first cancer to appear after radiation exposure, because of its short latency time of 2 to 10 years), does not appear to be elevated, even among the recovery operation workers. Neither is there any proof of other non-malignant disorders that are related to ionizing radiation. However, there were widespread psychological reactions to the accident, which were due to fear of the radiation, not to actual radiation doses."

People's fear is very real and important. But it's not substantiated by facts.

Comment Re:Nuke power (Score 4, Insightful) 483

A fantastic summary, but I quibble with the "no evidence of any significant release of radiation" quote for Fukushima. Two months ago, I would have said it was impossible for a reactor in Japan to contaminate the drinking water in Tokyo, but that's exactly what happened. To the detriment of the industry (and I'm a nuclear engineer), there was a significant release of radiation.

That said, in the grand scheme of things, it has not presented a harm to the general public that is greater than other risks: look at the poor folks in the spillways of the Mississippi. Or the coal ash spill from the coal-fired plant in Kingston, TN.

Three incidents like you describe above, over thirty-two years, is a pretty darned good safety record, with the 440+ commercial power reactors around the world. Why does nuclear have a bad rap? One possibility is it stems from fear since it all started with a few mushroom clouds, but whatever the reason, it seems awfully visceral.

Comment Re:Midrange (Score 4, Insightful) 275

I agree completely with HuguesT, above. The notion that universities are "just barely scraping by" is absurd.

College Tuition has been rising at about twice the rate of inflation over the past ten years. If you look at Harvard's endowment, they could easily pay every student's tuition based on extremely conservative returns on their 26 billion investment.

Colleges and universities are a racket. Few other industries, as a whole, have experienced the same kind of wholesale constant increase in funds like the education market.

Well, except for the defense industry, but that's another story.

To get back on topic, donating voting shares to MIT would have been a very interesting opportunity for students -- they would get to run the company, and learn all about the real-world application of technology. Alas, with dividends only, I'm not sure there's as much education going on as there could have been.

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