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Comment Re:Cake or death (Score 1) 855

There *should* be zero tolerance for some behaviors. If someone is harassing one of their workers, in addition to behaving immorally and illegally, they are driving away talented people, and exposing the company to huge lawsuits.

Why should anyone ever be given a pass for this sort of behavior?

More minor offenses are a different matter, but a manger asking a direct report for sex is not a borderline case.

Comment Re:That's pretty stupid. (Score 1) 307

Fiber optics goes black very quickly in high radiation.

Getting the extremely radioactive and hot fuel onto a train would be rather tricky.

Burying in cement is not a bad idea, but they probably need to make sure that the radioactivity isn't generating so much heat that it would melt its way out of an enclosure.

Comment Re:Is it really that hard? (Score 1) 156

Difficult because the hot side temperature needs to be very hot, but not crazy. The ability to use standard silicon would vastly reduce the circuit size, and maybe power consumption.

If pumps and motors can work at Venusian temperatures, then a cooler would not be all that difficult. Motors are probably needed for the lander to do useful stuff anyway.

A TEC cooler would be better, but I'm not aware of any thermometric materials that can work at that temperature. There might be a trick using a ferromagnetic material with the right Curie temperature.

The high temperature semiconductors are also a reasonable approach and a nice technology for other applications as well.

Comment Re:Rotary wings are not very energy efficient. (Score 3, Insightful) 63

Agreed. Hovering requires thrust > weight. Power goes as mass/time * velocity^2, while thrust goes as mass/times * velocity. So to have efficient thrust for lift you need to move a lot of air slowly, not a little air quickly. This is why helicopters have enormous swept disk areas. Any design that uses less area will be less efficient than a helicopter - already a very inefficient device.

Less efficiency means less range (already a problem with an electric), heavier motors and batteries, AND more noise and down-wash damage.

Tilt rotor sounds great, but adds a lot of additional weight and complexity on an already very marginal system. It allows high cruise speeds, but it takes time to climb and accelerate / decelerate, while navigating crowded airspace. Cruise speed tends to be an issue mostly on much longer trips than 50 miles.

So, how is this better than a single person helicopter?

Then, even if it works, where can it be used? No way noise ordinances will let someone use it from their back yard or city street At least in the US aircraft need to carry a half hour of spare fuel for safety. There are air traffic control issues if there are more than a few of these.

I just don't see a use case that wouldn't be better served with a conventional (but autopilot controlled) helicopter.

Looks like marketing silliness to me. I'll believe it when I see a working prototype

Comment Not technically reasonable (Score 1) 140

The 3d image shows a vehicle with small ducted fans for lift, and minimal aerodynamic lifting surfaces.

Helicopters use very large blades because (for very basic physics: momentum goes as MV, power goes as MV^2) it is more efficient to move a lot of air slowly than a little air quickly. So it will need more power than a helicopter which will make it less efficient, noisier, and the down-wash will be more damaging.

There may be a few applications where the lack of exposed blades will help, but not many. Even if the blades are enclosed, the very high power downwash will prevent landings near anything even slightly fragile.

Helicopters look the way that they do because that is the best design.

Small quad-copters make sense in applications where efficiency and noise are not critical.

Self flying is great, but that technology is mostly available now anyway

Comment Re:Well, duh. Mass transportation is a slush fund. (Score 1) 408

Probably not really incompetent.

I've been involved in a number of government funded projects where the process was:

Government: we need a *thing*, as cheap as you can.
Vendor1: OK, we can build your *think* for X dollars.
Government: X is too much, we can only fund it if its X/2.

Now there are two choices.
IF Vendor 1 responds with "OK X/2 it is", Vendor 1 gets X/2 dollars, then later get an additional X/2 to finish the project
OR
IF Vendor 1 responds with "Sorry, X is the cheapest we can do", then Vendor 2 will respond with "We can do it for X/2". Vendor 2 gets X/2 dollars, then later get an additional X/2 to finish the project

Many of these projects take so long that the people who budgeted and approved them, both in the government and at the vendor have moved to other jobs before the inevitable overruns become apparent.

Comment Not enough content on streaming (Score 3, Interesting) 84

Netflix seems surprised people are not dropping the DVD service, but a lot of content is NOT AVAILABLE on streaming. I total number of titles it may seem OK, but recent blockbusters generally appear on streaming long after they are on netflix DVD.

I'd love to drop DVDs, but netflix doesn't provide the right content on streaming.

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