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Comment Re:Red and Brown Dwarf companion stars... (Score 1) 139

"...Also, most binary systems have very tight orbits between the companion stars--a binary system with 1/2 a lightyear distance might be even more unusual than a unary star system..."

I just ran this through a three-body analysis program, and it shows a common valid solution path for this type of orbital system. I am going to publish my results of the resultant curve and call it the "Unary Track Inflection".

Comment Re:Great assumption (Score 3, Insightful) 400

I am a lighting engineer...

LED lamps are used all the time in aviation, where they are certified for high humidity, immersion, salt spray, and temperature extremes. It is commonplace to seal them and use conductive heat sinks to dissipate the internal heat. Thermal failure problems are well understood and well mitigated.

CFL fixtures can also be easily protected. It is all about using the right lamp type for the right job, no one is claiming that a CFL is the best for commercial street lighting, for example, where sodium lamps offer superior benefits, and especially not in an oven!

With regards to color vs energy, CFLs and white LEDs use a phoshpor to reradiate a broader color spectrum. The efficacy losses due to light outside of your visual spectrum are a very small fraction of the total output. While your comments with regard to color quality vs aesthetics are important, you assumptions about color vs efficacy are more or less false.

And one more aside, I'm even using standard spiral CFLs in my outdoor porch and carport now exposed to rain and weather, with no problems. They've lasted over 2 years now.

Comment Re:Best pirate repellent of all (Score 1) 830

"but how long before a scared poorly trained sailor has emptied that clip? whereas a watercannon and LRAD wont run out of ammunition, and are probably a bit easier to aim"

Ridiculous. Are you seriously claiming that bullets are more difficult to store and supply than hundreds, even thousands, of gallons of water? Why, all that water ammunition would have to be accounted for in the ship's hold for instant readiness, reducing stability, reducing cargo, truly ridiculous. Why, one could think up even crazier schemes such as actively sucking these thousands of gallons from some "convenient" mass of water nearby, I suppose you'd just throw our a hose and...oh...wait...never mind.

Comment Re:Whoopie for cold light! (Score 1) 553

Yep, this is exactly what's done. I'm a lighting engineer, and you simply tailor an array of Red/Green/Blue/Yellow/White LEDs with a controller to get whatever light mix you want. Individual portions of the array can be PWM controlled separately, letting you essentially design to almost any spectral output you desire (money permitting, of course.) Typical for a "comfortable warm incandescent feel" is White with Yellow.

Comment Re:If they are still not dimmable they still suck (Score 1) 553

Yes, agreed. I'm a lighting engineer, and do a lot of LED dimming and color-transition-effect arrays of LEDs. In the case of arrays, some LEDs may be driven full bright and the output color may still appear to at full bright, but you can still get flicker when one of the RGBW LEDs in the array is being driven at a low frequency to achieve a particular output color for the array.

I'm very sensitive to flicker, and can definitely notice many of the dim states at low frequencies.

For reference, an 85 Hz CRT was barely tolerable for me, and I needed 100 Hz or greater to avoid piercing headaches at the end of the day.

Comment Re:stupid question but..... (Score 1) 563

Related to wife packs all of her digital MRI records around on DVDs, it's very cool and fun to browse at home also.

Her scanning lab place, for some reason, does not archive the digital data for more than a year and imposes the archiving burden on the physician/hospital that they transmit to. A physical DVD is mailed and then physically filed at the hospital, with all of the pitfalls and human errors inherent in filing of paper records. Guess what happens if the hospital staff is flaky and doesn't file it correctly? Poof, gone. It's happened to us on a couple of occasions. DVDs binder-clipped to my wife's paper records and scratched all to hell? Seen it.

We discovered incidentally that while the firm labels the disk case with the record info, patient name, etc, the DVD itself is unlabeled. A doctor left our MRI DVD in the disk tray of one of the exam room PCs once, but didn't remember which one. We had to drive back to the hospital and go from room to room all over the floor checking DVD drives for the misplaced disk, or my wife would have "lost" her MRI records.

Digital is not the panacea one thinks, humans and bureuacratic offices are ingenious at screwing things up.

Comment Re:LEDs should last forever but apparently don't (Score 2, Informative) 685

I'm a lighting engineer that helps design LED systems...

Those failures are likely not the LEDs, but are the fault of the controller components. Like any electronic, cheap components become the weak link in the chain, and skimping money on the controller results in shoddy quality in the unit as a *whole*, even if the LEDs are perfectly fine (and I would bet that the LEDs are still perfectly fine.)

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