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Comment Re:Why does the ESA have a worse record of landing (Score 1) 72

NASA picked up a lot of experience putting landers on the moon. The Soviets also sent a lot of moon landers, but never really ironed out the bugs (had a lot of failures). Those problems followed them to Mars where they went 0 for 6 (well, 1 for 6 but the single success ceased communicating after 14.5 seconds with no useful data received).

Comment Re:Oh Boy (Score 1) 122

Current Li-ion batteries only have about twice the energy density of NiCds. The reputation NiCds got for having lousy energy capacity was due to a memory effect. If you kept recharging the battery before it had been fully discharged, it "learned" the low charge state as its new zero state, and you lost that bottom portion of its capacity (due to crystalline growth).

Rechargeable batteries have increased about 2x in energy density in the last half century, and about 3.5x in the last century (from lead-acid to li-ion). So claims of a 10x increase in the near future are going to be met with a lot of skepticism.

Comment Re:67% is not that good (Score 1) 126

When you're pushing the boundaries, anything over 50% is good.

Is it? It depends on the data, the model, the thresholds for "correct forecast," etc. There are lots of places in the world where a "persistence" forecast (i.e., today will be the same as yesterday) will net you a greater than 50% accuracy within a reasonable margin of error. And one should also always consider forecasting models against general predicted climate averages. Again, taking those into account, a forecast system just using climate averages might do pretty well too.

It really depends on what the percentage "accuracy" means in this case and how it was measured. I'm guessing they wouldn't bother reporting it if it weren't significant, but just how significant is difficult to tell without the details (and it seems the full research paper is behind a paywall).

Otherwise citing a number like "62% accuracy" is utterly meaningless. If you had a task like, "Guess how tall the next person to walk into the building will be," and I achieved 62% accuracy, that could be remarkable and improbable if the margin of error was 1/8 of an inch. But if I instead was guessing "Taller than 1 foot or shorter than 1 foot," then 62% accuracy might mean I'm mentally retarded.

Comment Re:The IoT as a connection? (Score 1) 72

Ahuxley, I appreciate the thought that went into that, but all that isn't necessary.

Just put a couple of car batteries in a drug house to power a brute-force broadband R.F. noise generator and broadband amplifier to be kicked on when the lookout gives the signal a raid is incoming.

Not only no remotely-controlled drones, no police radios, no cellphones, nada. If it ain't wired together it ain't talking, at least within a few blocks. No tactical comms, no calls for backup, no alerts about fleeing suspects, no calls for med-evac for wounded.

And, it's a lot cheaper, far easier to make, and less labor-intensive.


Comment Re:Why does the ESA have a worse record of landing (Score 1) 72

I appreciate the explanation, but isn't it more that the new system was added in rush (to replace the old ones) as opposed to it being the first time used? It seems like the NASA successes were first time uses of those landing systems also, from what I remember.

Also, I really don't understand how IP applies since these are not products for commercial sale nor used for commercial purposes. I don't see where NASA could even bring a suit.

Comment Not Practical (Score 1) 122

You can't just handwave away the massive cost of proving a charger per parking space, nor even the cost of an outlet per parking space along with the electrical lines buried capable of having every single parking space drawing enough current to charge...

Even if that were practical what exactly do you imagine will happen to someone's personal charging cables or equipment left unattended overnight. Thieves are taking copper pipe out of buildings with the water still on...

Comment 3D first, self-flying much easier (Score 1) 52

Great. Let me know when it's bulletproof in a 2D environment and I'll consider the 3D version.

That's actually backwards. Solving for the 3D case is vastly simpler, because while in the air you have very few obstacles to content with, you basically just have to be sure you can react to other planes, and have programmed in the coordinates of no-fly zones - otherwise travel is just a straight line. There are already drones that can find their way back home if the control signal is lost, and almost drones that can fly around tree branches without hitting them...

For takeoff landing you can simply dictate that a solid volume of sufficient space must be below or above you to land/takeoff.

Comment It can be solved - the solution is Hydrogen (Score 1) 122

I've noticed that also in the past when traveling and staying with friends in Europe.

That's why I still think the future for most electric cars will end up being hydrogen, not battery power - though with advancements like these battery may be a higher percentage, especially if you could go somewhere just one day a week to spend a half hour charging.

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