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Comment: You want references? LNT isn't a useful model. (Score 1) 230

by Behrooz (#47495751) Attached to: EPA Mulling Relaxed Radiation Protections For Nuclear Power

The difficulty being, your references are estimates based on what dose threshold?

Well, you have to go three citations deep to reach the original model they're working off of. Which turns out to be a conservative application of Linear No Threshold. Which... isn't actually testable for any reasonable value of statistical significance over the populations they're attempting to apply it to.

The BEIR VII risk models are a combination of excess relative risk (ERR) and excess absolute risk (EAR) models, both of which are written as a linear function of dose, depending on sex, age at exposure and attained age. The BEIR VII risk models were derived from analyses of data on the Japanese atomic bomb survivors for all cancer sites except breast and thyroid; for the latter, they were based on published combined analyses of data on the atomic bomb survivors and medically exposed cohorts.40, 41 To estimate risks from exposure at low doses and dose rates, a dose and dose-rate effectiveness factor (DDREF) of 1.5 was used for all outcomes except leukemia.

The biological effects of acute radiation exposure >1 Gy are reasonably well-known, are the basis for the linear-no-threshold model, and completely inapplicable to this sitation, as even the most-exposed workers at the Fukushima accident site did even approach this dose, despite the multiple situations where workers were exposed to doses in excess of legal limits.

The biological effects of short term dose less than 0.05 Gy or low-dose long-term exposure are also reasonably well-known, in that there is no statistically significant effect.

Unless you're dealing with the aftermath of a global thermonuclear war, the linear-no-threshold model is nearly useless from an epidemiological perspective, and so are conclusions reached using it.

Comment: Re:Is this new? (Score 1) 702

I travelled with a large external hard disk as well, once - which also got taken to one side and swabbed for stuff. Internal monologue: OH NO MY PRECIOUS DATA ... Oh, it's just the possibility of it being a bomb they're worried about.

On another occasion, I had fun with my home-made, Arduino-powered dSLR timelapse gadget - it got thoroughly inspected by the TSA. I'd already opted out of the backscatter X-ray whatsit, only for a swab-for-explosives test to give a (false-)positive. Eek. Cue being taken to one side, where they looked in my bag and found the timelapse-o-tron...

To give the screeners their due, they let me go after a few minutes - after I'd heard their complaints about the potential radiation doses they and the passengers were receiving from the backscatter X-ray thingers, and after I'd provided advice on what sort of camera to look into buying for a budding photographer.

Security fun elsewhere: carrying a plastic bag of loose change through the Eurostar security in Brussels (it basically looked like an amorphous, completely opaque lump on the X-ray) - and a random customs check at a UK airport giving a (false-)positive swab for some sort of illicit drugs. Eek.

Comment: Re:The worlds largest optical/near-IR telescope (Score 2) 76

The worlds largest single dish telescope is still the Green Bank Telescope (http://en.wikipedia.org/wiki/Green_Bank_Telescope), which at 100m is ~6x the size.

World's largest fully-steerable single-dish telescope - the Arecibo Observatory is larger still at a diameter of 300m! (Impressive Arecibo exploration video here. The thing's sodding enormous.)

I went looking for the largest diameter multi-dish radio telescope. It looks like the biggest terrestrial 'telescope' is the Global VLBI system created by combining the European VLBI Network with the US Very Long Baseline Array - it's like some massive team of superheroes combining to save the Earth from some terrible secret of space. Or whatever. Apparently they can also add space-based telescopes when that just isn't enough. Which, quite frankly, is showing off...

My thoughts when seeing one of the beautiful, 10m diameter Keck optical telescopes up close a few years ago? I've had full control of a telescope bigger than that.

Radio Astronomers: Compensating For Something.

Comment: Re:Reminder (Score 2) 46

I dunno, I always get a big belly laugh whenever I log into something and see that horrible 1980s B&W X11 desktop, complete with ugly 'X' cursor.

Try flying on a Virgin America plane with the LCD screen inflight entertainment systems in the seat-backs. They'll often mass-reboot the things before or after a flight, briefly revealing that retro-fantastic, monochrome stippled background with 'X' cursor...

Comment: Re:speed of light (Score 1) 374

by Behrooz (#46352425) Attached to: Report: Space Elevators Are Feasible

Technically, 29.9792458N Latitude constitutes a ~1cm band around the northern hemisphere. The Grand Gallery is oriented roughly north-south, and at 46m long in itself occludes 0.00043 latitude-- so you'll miss almost all of it.

Fortunately, there is a much more useful application for random decimal numbers associated with SI constants. If you happen to be flying over Africa and become lost, follow your GPS to the scientific notation of the Planck constant degrees east, then fly north, and you'll eventually reach Mohamed Boudiaf International Airport in Algeria.

Moon

NASA Now Accepting Applications From Companies That Want To Mine the Moon 251

Posted by samzenpus
from the getting-some-cheese dept.
cold fjord writes "The Verge reports, "NASA is now working with private companies to take the first steps in exploring the moon for valuable resources like helium 3 and rare earth metals. Initial proposals are due tomorrow for the Lunar Cargo Transportation and Landing by Soft Touchdown program (CATALYST). One or more private companies will win a contract to build prospecting robots, the first step toward mining the moon. Final proposals are due on March 17th, 2014. NASA has not said when it will announce the winner."
Shark

Many Lasers Become One In Lockheed Martin's 30 kW Laser Weapon 202

Posted by Unknown Lamer
from the ready-main-phaser-array dept.
Zothecula writes "In another step forward for laser weapons that brings to mind the Death Star's superlaser, Lockheed Martin has demonstrated a 30-kilowatt fiber laser produced by combining many lasers into a single beam of light. According to the company, this is the highest power laser yet that was still able to maintain beam quality and electrical efficiency, paving the way for a laser weapon system suitable, if not for a Death Star, for a wide range of air, land, and sea military platforms."

Comment: Fuck the 'rule of law.' (Score 1) 822

by Behrooz (#46086757) Attached to: Ask Slashdot: What Does Edward Snowden Deserve?

I think you have a misunderstanding. In our society, the 'rule of law' is based more on color, wealth, politics, connections, and whether the justice system 'likes' you than on innocence or guilt.

*fuck* the rule of law. Laws have no judgement, rationality, and are subject to incredibly selective enforcement by cops, prosecutors, and the coercive apparatus of the government as a whole, entirely at the whim of officials who have no accountability or responsibility.

You really want a system where innocence or guilt is decided based on social class and race? Because that's where we're at right now.

If you'd like to talk about the rule of law, we can talk about our broken court system, where innocent until presumed guilty is a legal fiction, and better than 90% of crimes are resolved with a plea-bargain rather than a trial.

It's all a sham, and 'justice' is entirely illusory unless you're wealthy, educated, and connected enough to game the system. This is one of the (relatively few) places where the tea party and libertarians really have a solid point.

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