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Comments

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Big Bang Actors To Earn $1M Per Episode

drerwk Re:Nerd Blackface (442 comments)

Do you really think that an IRL Sheldon without script immunity would be able to do the same? The TV Sheldon also seems to be a pretty crap physicist, given to conspiracy theories, junk science, and an inability to distinguish between fiction and reality.

I was an undergrad Physics major at Caltech. Other than the crap physicist qualifier, I knew professors in the department who were given to conspiracy theories, junk science, and an inability to distinguish between fiction and reality, though not all in a single individual.

about three weeks ago
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Perlan II Project Aims To Fly a Glider To the Edge of Space

drerwk Re:"and designed to fly near transonic speed" (44 comments)

The lift produced by a wing is partly a function of the rate of air mass that passes over the wing. Keeping density constant an increase in velocity will increase lift. If the density of the air decreases, as it does with altitude, then one must increase velocity to get the same air mass to pass over the wing and generate the same lift. At the altitude they will be flying, they may well have to fly near the speed of sound to get enough air over the wing to provide sufficient lift. The higher they go, the higher their stall speed so they end up flying in a decreasing envelope between speed of sound and stall. The typical airspeed indicator is a static ram pressure transducer, which is also dependent on the mass of air impinging on it, so it will indicate 'normal' stall and flying speed even though the plane is going much faster.

about a month ago
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NASA Tests Microwave Space Drive

drerwk Mod up - and thanks. (201 comments)

Mod up - and thanks for dropping the $25 to inform the rest of us.

about 1 month ago
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Unintended Consequences For Traffic Safety Feature

drerwk Re:OR (579 comments)

One could argue that in most cases, a pedestrian paying attention could have avoided getting ran over if they'd pulled their heads out of their phones long enough to look around them.

SFPD claims to be keeping better stats these days but I could not find them online.
However here is what I did find: http://www.ktvu.com/news/news/...

All three victims this year entered the crosswalk only after pushing a button to activate several flashing beacons to alert drivers to stop. There are six lanes of traffic across Sunset with an island in the middle. Thursday's crash occurred when several drivers stopped, but a Honda CRV kept going. The driver noticed the woman too late and skidded into her, clipping her with the front bumper and spinning her to the pavement. "She said she didn't see her, " San Franicsco Police Officer Gian Tozzini told KTVU. "I don't know how she didn't see the flashers. Maybe they're just looking forward and not paying attention."

That is three victims, one fatally injured, at a single crosswalk with flashing lights in the Sunset. The description matches what I see in my little New England town where I'll slow because I see a deer stepping into the road and the car behind me thinks they need to pass me on a two lane road so as not to slow down at all - not sure how bad I'd feel other than for the deer. A pedestrian was hit in our crosswalk same way - one car stopped, person started walking, car behind did not even slow down and passed in the next lane hitting the person in the crosswalk - actually tossing them into the front window of another car that had also stopped on the other side for the pedestrian - that car was full of kids coming home from little league.

about 2 months ago
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Ask Slashdot: Are You Apocalypse-Useful?

drerwk Re:magical scenario where (737 comments)

So running a conductor through a changing magnetic field will no longer produce a charge?

No it won't. It will produce an electric field which can be used to push charges around, but will not produce a charge.

Putting two lead oxide plates in an acid batch will no longer cause a chemical reaction?

Nope - no electrochemical reaction. You need metals of differing electronegativity, like Pb and PbO2.

My goodness, I was unaware that a catastrophe large enough to cause an apocalyptic event would change the fundamental laws of physics.

You're right it won't, but you might want to brush up on what they are before the apocalypse.

You sound young.

...

about 5 months ago
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Smart Car Tipping Trending In San Francisco

drerwk Re:Smart Cars = HiTech ??? (371 comments)

That has always bother me too. I'd much rather get an old 2CV - 48 mpg, 4 people seated in comfort, front wheel drive. Not a single thing better than a 60 year old French marvel of engineering.

about 5 months ago
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Smart Car Tipping Trending In San Francisco

drerwk Re:It's not trending. (371 comments)

Seriously? Never wondered what it would feel like to hit a baseball across the street and through a window? Never wondered what the sound would be like and not thinking beyond the cool sound of breaking glass tossed the ball up and let swing. And then in unexpected joy realized you hit it perfectly, to hear the glorious sound of that window break only to have your stomach sink to the depths realizing that you broke a damn window?

about 5 months ago
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Killing Cancer By Retraining the Patient's Immune System

drerwk Re:Avoid cancer (175 comments)

I am sure you can lower the risk with dietary choices. But in fact genetic mutations that lead to cancer do just happen - that is more physics than choice.

about 9 months ago
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How Many Android OEMs Cheat Benchmark Scores? Pretty Much All of Them

drerwk Re:Wrong, they are boosting clock speed above norm (189 comments)

There is no way to build a game on Android that can run at the speed the benchmarks are getting run at on each of the devices "cheating".

What happens if you name your game to match the benchmark that the phone is looking for?

about a year ago
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Time For a Hobbyist Smartphone?

drerwk Prograph (207 comments)

See http://en.wikipedia.org/wiki/Prograph
I loved using this in the mid 90s. I was 5x to 10x productive. But there was no diff available, no way to do SCM, it was hard to come back to code I'd written 6 months before and refresh my memory of what it did. And it was next to impossible to collaborate will a team. I was forced to use http://en.wikipedia.org/wiki/Executable_UML using some horrible tools (Kennedy Carter iUML) in the 2005s - same exact problems.
Now iBuilder or what ever the I tool is in XCode is pretty nice. But building software that works, is maintainable, is extendible, and so on is a hard task - I don't think it is the lack of drag and drop tools.

about a year ago
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A New Spate of Deaths In the Wireless Industry

drerwk Re:Acrophobia? Don't watch. (247 comments)

No, that is not my video. I can watch it till 1:40. When the guy goes outside the mast that's when my stomach feels like it is in free fall.

1 year,10 days
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A New Spate of Deaths In the Wireless Industry

drerwk Mod up please (247 comments)

wish I had known - thought that was weird.

1 year,10 days
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Electric Vehicles Might Not Benefit the Environment After All

drerwk Re:Depends on the energy source duh! (775 comments)

http://www.theworld.org/2012/11/the-energy-costs-of-oil-production/ “Back in the 1920’s, oil was paying off at 100-to-1,” said Zencey. “It took one barrel of oil to extract, process, refine, ship and deliver 100 barrels of oil. That’s a phenomenal rate of return. If you work out the percentage, that’s a 10,000 percent rate of return.” But that’s not the rate of return today. Now, conventional oil production worldwide pays off at about a 20-to-1 ratio. And in Canada, where the oil comes from tar sands, it’s closer to 5-to-1. “Renewable energy sources are paying off at higher rates, 12-to-1, 15-to-1, 17-to-1. That tells you right there, hmmmm, the age of oil should be over.”

about a year ago
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Book Review: Creating Mobile Apps With JQuery Mobile

drerwk Re:That explains things (91 comments)

I like that: re-event the wheel. I'll see if I can't use that in my next jqm ui presentation.

about a year ago
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Curiosity Rewarded: Florida Teen Heading to Space Camp, Not Jail

drerwk Re:Good to see intelligence rewarded for once. (241 comments)

It's more complicated than that

"Unfortunately, what she did falls into our code of conduct," Leah Lauderdale, a spokeswoman for the district, tells Riptide. "It's grounds for immediate expulsion." More specifically, Wilmot's mini-explosion -- which came after she mixed "common household chemicals" in a plastic bottle -- violates Section 7.05 of the school's conduct code, Lauderdale says, which mandates expulsion for any "student in possession of a bomb (or) explosive device... while at a school (or) a school-sponsored activity... unless the material or device is being used as part of a legitimate school-related activity or science project conducted under the supervision of an instructor." ...Wilmot's principal ack

http://www.fedcoplaw.com/html/Federal%20Explosives%20and%20Bombing%20Laws.dwt.htm
Not obvious to me that what she had qualifies as either a bomb or explosive.

about a year ago
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A Cold Look at Cold Fusion Claims: Why E-Cat Looks Like a Hoax

drerwk Re:Need to Be Careful (426 comments)

I looked at the top three Google links for Dr. Peter Hagelstein. Could not find anything other than he is still an associate prof at MIT - would think CF would get you tenure. Would you mind pointing me to some CF success? And I'll constrain that to the definition where success means repeatable.

about a year ago

Submissions

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Powering the Planet

drerwk drerwk writes  |  more than 7 years ago

drerwk writes "An article in the Caltech magazine Engineering and Science by Prof. Nathan Lewis gives a clear and cogent argument that solar is the only likely solution in the next fifty years to the clean energy problem. Discussions on /. regarding clean energy run the gamut and include arguments regarding nuclear, fusion, solar, coal and so on. In contrast, Prof. Lewis's article covers the pros and cons of these same arguments with actual journal references. Let's hope those paint on solar cells are coming soon!

This talk was the opening keynote speech at the first annual California Clean Innovation Conference, held at Caltech on May 11, 2007. The event, a partnership with UCLA and UC San Diego, included discussions on the futures of assorted energy technologies and how to finance them. In other sessions, clean-energy startup companies were given the opportunity to "fast pitch" their business plans, in three to five minutes each, to a panel of venture capitalists. Nathan S. Lewis (BS '77, MS '77) is Caltech's Argyros Professor and professor of chemistry. Much more on global energy issues and on his own research in solar power can be found at http://nsl.caltech.edu./
"

Link to Original Source

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