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Comment Re:Sand Storms (Score 2, Informative) 386

With a DC line the loss can be figured to be due to conductor resistance. A back of the envelope calculation shows that to get 3.5% loss per 1000km would require each pole to have ~5,000mcm of aluminum conductor. At 600kV, it would be a good idea to use a bundle of 4 conductors to reduce corona loss, so each conductor would need to be ~1,250mcm of aluminum, which is a common size for ACSR conductors.

1.1% loss per 100km sounds more like a 230kV AC line.

Comment Re:Carbon free power (Score 1) 98

Um, 131I has a half life of 8 days, you may have been thinking of 129I with a half life of 16 million years. 90Sr has a half life of 28.8 years, so it will be pretty much gone in a few hundred years. 137Cs has a half life of 30 years and as with 90Sr, will be pretty much one in a few hundred years - figure the radioactivity declining by a factor of 10 for every century.

Considering that King Tut's tomb lay undisturbed for ~3,000 years, it doesn't seem to be too much of an effort to keep spent fuel isolated for a few thousand years.

Comment Washing Machine hacks? (Score 2) 481

One hack I'd really like to do is a warm rinse cycle on a washing machine. A 15C increase in water temperature can make a big difference in rinsing effectiveness. My first washing machine did have a warm rinse cycle, but the US Govt, in their infinite wisdom, decided to require washing machines to only use cold water for rinse.

Comment How about LIS as in the original pilot? (Score 1) 169

The pilot for LIS, which lacked both the robot and Dr Smith, was very promising. Guy Williams stood out very well in the pilot and was grossly underutilized in the series. I would go so far as to say the pilot for LIS was better than the original pilot for Star Trek (the one with Christopher Pike).

I could go either with respect to Dr Smith in a new series - the pilot had a hokey run-in with "asteroids" causing the Jupiter II to go off course, which was part of the plot for an episode in the third season - the one where Dr Smith does time travel and DOESN'T board the Jupiter II, which leads to the J2 being destroed when hitting uncharted asteroids.

Comment Re:Despite the summary, this is somewhat new... (Score 1) 80

The Leidenfrost effect is a form of film boiling. The bad news is that film boiling will take place on vertical surfaces about as easily as it will on horizontal surfaces. The one sure way to stop film boiling is to keep the heat transfer rate well below the departure from nucleate boiling limit (nuclear reactors are design to have the peak heat transfer rate at least 3X below the departure from nucleate boiling limit) and never let the circuitry become dry when powered.

Comment Re:Humans remain better sometimes (Score 2) 242

Such as when the center engine of a DC-10 goes "bang", cutting off the hydraulics and the only control is from adjusting the throttles of the remaining two good engines?

And for atrophied skills, consider Air France 330 (IIRC) from 2009, which was flown in a controlled stall into the Atlantic Ocean because the co-pilot forgot that recovery from a stall requires the nose to be pushed down. Original cause was autopilot decoupling when the pitot tube got iced up.

Main problem with computer control is trusting that the people writing the software properly anticipated all of the situations that could be encountered. The quality of most code leaves me with a bad feeling about this. An example, an Airbus on a demonstration flight crashed because the software countermanded the pilot's attempt to pull out of a dive, the software was trying to prevent excessive g-loads but the programmer didn't consider that hitting the ground would be worse than bending the airframe.

Comment Re:Vitality is defined by users, not developers. (Score 1) 149

FWW, Motif was an HP development where a fair amount of effort was put into making a more or less intuitive Window manager that was a bit better looking than what M$-Windows looked like at the time (ca 1990). Visual User Environment was built on top of Motif, and that morphed into CDE in the mid 1990's.

There have been a few open source apps built on motif, Nedit and Xephem come to mind. Tcl/Tk was first built on Motif.

Comment Re:Why all the desktop stuff? (Score 1) 149

Solaris had been running on x86 since about 1990. One motivation for running on two different processors is that the porting process uncovered a fair number of bugs, I would go so far as to say the reputation of the open source UNIX software from the late 1980's and early 1990's was due to the process of porting to the various flavors of UNIX.

Sun was in the process of migrating away from CDE when Oracle bought them, so implementing a desktop was more a matter of porting GNOME and KDE to run on Solaris. The Firefox ports to Solaris were done by a Sun's software group in China and Sun was paying Adobe to support Acroread and Flash on Solaris.

Comment Re:No additional hardware was likely needed (Score 1) 153

I disagree, as the author didn't seem to understand the reason why gasolene and diesel engines run on different fuels. Gasoline is composed of lighter hydrocarbons to give a higher resistance to compression ignition to reduce knocking, diesel is composed of longer hydrocarbons to enhance ignition by the hot air generated by compression.

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