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Comment: Re:He's right (Score 3, Interesting) 276

by Squirmy McPhee (#43513613) Attached to: Terrible Advice From a Great Scientist

And from my experience, publishing dozens of peer-reviewed scientific articles, your experience is the exception. In fact, many sciences do not even utilize technicians. In the ten or so laboratories that I have worked in/with and the labs of the numerous professors that I talk with about their publication policies, exactly zero will allow someone authorship on a paper that they don't see until it's "basically finished." I'm sure some fall through the cracks, though certainly not the majority. However, I would not generalize my experiences and neither should you.

My experience -- also publishing dozens of peer-reviewed scientific articles -- is quite different from yours and much more like that of the poster to whom you were responding. More than once I've found out that I was a co-author on an article when the publishing company contacted me to let me know that my article had been received for submission. That's even a step beyond what the first poster mentioned -- I didn't even see the article that I supposedly co-authored until after it was submitted for publication! I've also had my authorship credit manipulated so as to imply collaboration where there was none. It was accidental, I think, but afterward there was actually a story in the press about our non-existent collaboration.

Comment: Re:Well the ultimate value of Bitcoin is (Score 1) 605

by Squirmy McPhee (#43416819) Attached to: BitCoin Value Collapses, Possibly Due To DDoS

Good luck going to Safeway and buying your Jeno's frozen pizza with Euros, Yuan, or Yen, but they're all "real" money.

Good luck going to Safeway and buying your Jeno's frozen pizza with gold or silver, but a lot of people would have you believe that those are the only "real" money.

Comment: Re:Why focus on solar? (Score 3, Interesting) 129

by Squirmy McPhee (#41345121) Attached to: Towards a 50% Efficient Solar Cell

Why would the military focus so heavily on solar power?

It's not just solar, they are also very interested in wind, geothermal/ground source, and biofuels. But they think solar and wind have the most potential for their purposes (it's mostly only the Air Force interested in biofuels, for fueling their planes).

As for why, well, 80% of the convoys run in Iraq and Afghanistan are fuel convoys. On average, a soldier died or was wounded in one of every 46 of those convoys in 2010. And by the time you take into account the cost of the fuel and the expense of moving it, the military is paying something like 5-10 times the price you pay at the pump when you fill your gas tank.

What is this fuel used for? Some of it is used to power vehicles, of course, but the vast majority of it is used to provide electricity at remote and forward bases. They dump it in a generator, burn it, and wait for another convoy. On the other hand, the sun and the wind come to many of their locations without the need for a convoy.

The upshot of all of this is that with sufficient energy densities, the military could spend a whole lot more on solar panels and wind turbines that would seem justifiable to the average homeowner and still have it be economical -- I mean, just think of the money and lives that could be saved if a base could reduce the number of convoys it needs by 80%.

For all of that, you probably don't need cells with 50% efficiency, and I guess that's why TFA focuses on soldiers' gear instead of base power.

Your concern about a soldier contending with solar panels hanging off his back is a bit misplaced, I think. TFA says that at 50% efficiency, a 10-cm square panel is all that would be needed. That is already smaller than a single standard silicon cell in production today (standard is 15-cm square). And if you're worried about bad weather, sandstorms, and distractions then I would think that the last thing you want is a mechanical device with moving parts like foot pedals.

Comment: Re:No. (Score 2) 129

by Squirmy McPhee (#41345065) Attached to: Towards a 50% Efficient Solar Cell

It concentrates light from the entire sky into a narrow beam which is then split into different wavelengths. It says that right in the summary.

No, it doesn't say that in the summary. It says (incorrectly) that dichroic films are used to concentrate sunlight 20-200X, but nothing accurate about how it achieves that concentration. TFA says that for the concentrators to work, they would have to be pointed at the sun.

This is consistent with my personal experience. I've never seen a concentrator that can collect light from the entire sky and deliver it in a tight, focused beam. It's part of the reason concentrator systems have never quite managed to live up to their economic promise -- the diffuse portions of the solar spectrum go unused, reducing available energy by about 20% even in cloudless locations, and output drops to near zero as soon you have a few clouds or some haze.

And the dichroic films are used to split the light into its constituent parts, a bit like a prism. They play no role in the concentration of the light (though that is not your error).

Comment: Re:Isn't this expected behavior? (Score 3, Interesting) 131

by Squirmy McPhee (#39387763) Attached to: Websites Can Detect What Chrome Extensions You've Installed

If you don't like the behavior, you have quite a few options: Remove the extension, disable it, go incognito when you don't want your extensions detected, or simply use another browser

Hmm ... it seems I may have been a little too quick. When I visit the site running the extension-detection script in icognito mode, it is still able to detect my extensions. Now I wonder if disabling is even effective.

That said, I don't really think there's anything anybody can learn about me from the extensions I have installed -- at least, not anything that I wouldn't tell a total stranger. Since there are few extensions that don't interact with at least one website, I think that's a good policy to follow even if you're a Firefox user.

Comment: Isn't this expected behavior? (Score 1) 131

by Squirmy McPhee (#39387733) Attached to: Websites Can Detect What Chrome Extensions You've Installed

This "exploit" looks more like begging the question to me. As far as I can remember, every single Chrome extension I have installed warned me that it might share data with the websites I visit before I installed it. It stands to reason that if an extension can share data with a website, that website can detect the extension, does it not?

I'm not saying that it's ideal behavior, only that it seems to me that Chrome users have already been warned about it by Google itself. If you don't like the behavior, you have quite a few options: Remove the extension, disable it, go incognito when you don't want your extensions detected, or simply use another browser come immediately to mind.

Comment: Re:Good (Score 2) 261

by Squirmy McPhee (#37362528) Attached to: Power Demand From US Homes Expected To Fall For a Decade

Now maybe they can reverse that ridiculous incandescent light ban.

There is no incandescent light ban, despite what Joe Barton (who co-sponsored the "ban" in the first place) would like you to believe. There is only a mandate for lights to become more efficient -- there is nothing in the law mandating that a particular lighting technology be phased in or out. In the end, it is likely a moot point anyway as market forces (partly as a result of European regulations, which the US Congress can do nothing about) have been pushing incandescent bulb manufacturers to close factories. In other words, with or without the law, incandescents are on the way out.

Like others, I would suggest LEDs. The prices are coming down fast, and the quality (and directionality, or lack thereof) is improving fast. Right now you still have to be pretty careful about what brand you buy and such -- the cheapest available bulb is likely to disappoint -- but by the time you have a hard time finding the incandescents you need I suspect LEDs will be much more viable.

Comment: An MS will get you farther than two BS degrees (Score 1) 296

by Squirmy McPhee (#37301830) Attached to: Ask Slashdot: Best Second Major For a Mechanical Engineer?

If I were in your position, I would stick with the ME for now. For one thing, you can do a BS + MS in the same amount of time (or less) that you can do a double-major BS, and the MS will get you farther in the job market than a double BS. When you become an upperclassman, you will have the opportunity to choose electives from other departments, and maybe even some grad-level courses, which will allow you some limited space to explore your interests. If you're interested in controls, look to EE departments -- where I did my MS and Ph.D., the EE controls classes were filled with students from other departments. Perhaps other universities offer those in the CS department, but I doubt it. And don't limit yourself to controls: If you're interested in biofuels, maybe look for some relevant chemical or bioengineering courses. You should also look for undergraduate research opportunities, summer internships, and student projects that coincide with your interests (e.g., a solar-car-racing team, if you're going to a university that has one).

When you finish your BS, you will have a lot more opportunities to specialize during an MS year. Not only can you switch fields if you like (e.g., switch to CS if you think it is really the way to go), but many universities offer specialized multi-disciplinary MS and certificate programs that are targeted to specific skill sets. My university offered quite a few of those -- off the top of my head, I remember computer-aided manufacturing, a multidisciplinary semiconductor processing program, and a business certificate aimed at succeeding in the global (as opposed to American) business environment. Universities are now adding similar programs targeted at biofuels and other alternative energy technologies.

Comment: Re:Not exactly "free". (Score 1) 119

by Squirmy McPhee (#36341986) Attached to: National Academies Release Over 4,000 Free Science Books

I assume that you are aware that all these books were produced at US Government expense?

What gives you that idea? The National Academies are private organizations and the books they publish do not all result from federally funded research. Even so, the only publications that are automatically public domain are those of US government employees, regardless of the funding source.

Comment: Re:Yummy lovely toxic elements for only 3% efficie (Score 1) 204

by Squirmy McPhee (#35983176) Attached to: 80% Improvement In Solar Cell Efficiency

According to the article, part of the cell is composed of cadmium telluride. Both are toxic and various compounds of tellurium stink to high heaven. I wonder what happens if the cells get caught in a fire?

Right, the cell is composed of cadmium telluride, which is a binary compound. That is different from saying the cell is composed of cadmium and tellurium, which are separate atomic compounds with different properties. Toxicity and fire studies on cadmium telluride are ongoing, but so far they have found that cadmium telluride is not much of a threat. In fact, there was a chicken farm with cadmium telluride solar panels that burned down in Germany in late 2009, and while the place was treated by the authorities as a hazardous waste site, it was because of the chicken poo, not the cadmium telluride -- the burnt panels were collected and sent back to the manufacturer for recycling.

Put another way, assuming cadmium telluride is toxic and stinky just because it is composed of toxic, stinky elements is like assuming water is explosive because it is composed of explosive elements.

Comment: Re:What economic use? (Score 1) 38

by Squirmy McPhee (#34730522) Attached to: Solar Cells Integrated In Microchips

The only way I can see that one wins on cost with this technology is if one has electronics that are so low-powered that they can be powered by an amorphous solar cell with an area equal to that of the circuitry itself. If you need a point of reference on the practicality of this requirement, I point you to your average solar-powered calculator, which has a solar cell area of several cm^2, and an active circuit area of probably less than 5 mm^2.

According to the press release from University of Twente, they will use amorphous silicon or CIGS layers deposited on top of the integrated circuit. A pretty average amorphous silicon solar cell will produce 6 mW/cm^2 in full sunlight, and about 0.5 mW/cm^2 indoors. A CIGS cell, especially on such a small scale, could probably come close to tripling those figures (one of the biggest problems in realizing high CIGS cell efficiencies in mass production is getting layers of uniform quality over large areas, an issue that would be dodged in this case).

The press release from Twente says the power requirement is "well below 1 mW"; if you assume the actual requirement is 0.1 mW and you use CIGS cells then you could probably still get enough power to run the circuit indoors on 6-7 mm^2 area. That doesn't seem out of line to me, but then I'm a solar cell designer, not an IC designer....

Facts are stubborn, but statistics are more pliable.