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Comment: Re:Happened to me; easily reversed (Score 1) 798

by vsny (#42778711) Attached to: AT&T: Don't Want a Data Plan for That Smartphone? Too Bad.
I have the same issue with my old windows HTC smartphone. However I'm able to call and undo the data plan upgrade because old smartphones are grandfathered into the non-data plan options. I remember seeing some literature on this 3 or 4 years ago. Try this with a modern smartphone - I don't think they'll be so courteous and downgrade your plan.

Comment: Re:Here's what my 4 year-old loves... (Score 1) 742

by vsny (#34371212) Attached to: What To Load On a 4-Year-Old's Netbook?
Starfall looks like a great site. Thanks! I just played with my 3 year old and she loves it. She's so excited now she won't go to bed!

I think there are too many comments so far about sending your kid outside or buying physical toys. I think those comments are unrealistic or irrelevant. Of course your kid should go outside but what do they do after 5pm. Sure she has a room full of toys that she plays with. Dolls, toyhouse, legos, paint, clay, etc. But I want my kid to read as well.

Well-made software like this has built a strong desire for my daughter to read at 3 years old. Even reading books to her every night since she was 10 months old has not created as strong as a desire.

There is some great windows software as well - reader rabbit, key skills, and jumpstart. I like the software better than flash websites - for the younger kids you don't have to worry about them mis-clicking on the start menu, back button, etc. Just a minute ago my daughter right-clicked and was sitting at the adobe flash website wondering what to do next.

Comment: Re:Paper and Environment (Score 1) 446

by vsny (#32003864) Attached to: Paper Manufacturer Launches "Print More" Campaign
Thank you for some real data - instead of all the complaints "isn't it so obvious it's bad with chemicals, water, transport, blah blah blah".

It seems like we are pretty close to paper being a sequestration source.

Don't you think with technology improvements, avoiding certain bleaching and cleaning steps, and more efficient transportation it can cause a net reduction.

Isn't this an opportunity and not a problem?

Comment: Re:BS? (Score 1) 467

by vsny (#29887863) Attached to: Reliability of PC Flash SSDs?
From the anecdotal evidence just in these comments alone, CFL clearly have a very large distribution of failures. Maybe the MTF is accurate but the distribution or log-sigma is very large. I have had 4 fail within weeks and they are used 'appropriately'. I have never had incandescents fail in this way.

Yes I may have cheap bulbs. But they still have a long rated MTTF values listed on the box.

Sure, maybe the ones that do last will survive several million hours. I can say nothing about the MTTF, but clearly there is a very large distribution of failures which suggest very high early-failure rates. You really need to see the failure distribution statistics to determine how they came up with these lifetime numbers.

Comment: Re:How does it aim? (Score 4, Insightful) 287

by vsny (#29076281) Attached to: Airborne Laser Successfully Tracks, Hits Missile
They've proven that standard mirror materials will ablate and burn up very quickly with this laser power. Even rotating the missile does not help. The missile body still heats up significantly.

The laser optics in the airborne laser probably have to be made out of narrow band reflectors which in practice can be made more than 99.999% reflective to a laser. It would be easy to slightly change the laser wavelength and optics (a few nm's perhaps) and the missile would absorb again.

Comment: Re:Lumens per watt is? (Score 1) 553

by vsny (#26660407) Attached to: LED Lighting As Cheap As CFLs Invented
The reason Cree is so successful is the thermal conductivity of the substrate. Most vendors use sapphire and some do use Si. Look up the difference in thermal conductivity between sapphire, silicon and SiC.
SiC = 370W/mK, Si = 130W/mK, Sapphire=42W/mK

If you can run the LED cooler for the same input power the diode will be more efficient. This is why SiC based LEDs run better and more reliably.

Si substrate GaN LEDs have been around for years they just aren't very good. And it has nothing to do with cracking.

Comment: GaN on Si commercially available (Score 2, Informative) 553

by vsny (#26656925) Attached to: LED Lighting As Cheap As CFLs Invented
Commercial GaN on Silicon has been available for a years now. The commercial vendors have overcome this cracking problem due to thermal expansion using an AlGaN buffer since about 2005. One problem growing on Silicon is dislocations which limit lifetime, not cracking.

Actually sapphire substrates surprisingly are not that expensive.

I'm not sure why this press release is considered news.

Whenever a system becomes completely defined, some damn fool discovers something which either abolishes the system or expands it beyond recognition.