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Comment Re:It's not Obama (Score 1) 433

And this is totally unlike what every other president did who had a 747 to hop on to?

Ooh, good retort! Anything that another asshole in the white house did before Obama totally excuses him, even if he's wagging a finger at us driving cars while he rides in a fucking airliner.

When did it become OK to be patriotic and yet call the elected leader of this country "that asshole" instead of The President?

Anyone who hasn't called a president an asshole isn't a true American.

I have more respect and love for the country

Do you really not understand the difference between a politician and the country?


Comment Re:the main legit use i can see (Score 1) 267

I presume that this would be integrated with some kind of app on the receiver end. When the truck is dispatched (or, if the depot is in range, when the parcel is ready for direct dispatch), you'd get a message telling you the time window when it will be available. You then signal that you're ready to receive it and give some GPS coordinates. It's then dispatched and sends another message when it's a few hundred metres away. You then go outside (or stand on a balcony) and wait for it to be delivered directly to you. Once it's very close, it can use WiFi from your phone (send your MAC address to the drone and the SSID that you're associated with - or create an ad-hoc network if you're out of range and it can home in on you) to check that it's actually landing by the correct person. Then just tap the 'delivery received' button and it will fly away.

Comment Re:How does space elevator save energy? (Score 2) 156

No space elevator designs that are even vaguely plausible include a moving cable. To understand why, consider the mass of such a cable: the energy required to accelerate it and then decelerate it for the cars to start and stop would be phenomenal. You could potentially have a loop that would continuously move in a circle, but you'd still have problems starting it. Just dropping things from the top wouldn't be enough, because you'd need to get them a fair way down before they'd stop orbiting and actually provide force in the correct direction. I don't even want to think about the lateral forces that such a structure would have to endure.

Comment Re:Hydro = from the sun (Score 1) 204

Direct solar may sound nice and work fine in small scale, but collectors would have to cover great areas to be effective

The total world energy consumption is somewhere around 100PWh/year. That's around 274TWh/day. The sunlight hitting the Earth is around 1kW/m^2, so 8kWh/m^2 assuming 8 hours of sunlight. If you assume 100% efficiency in conversion (totally impossible, but we'll start there and refine later), then that means that you need about 3.45E10 m^2 of land devoted to solar power. That's a square about 185km on each side. If you assume 10% efficiency (mass produced photovoltaics are 12-25% these days), then you need an area about 342000km^2, or about the area of Germany, to power the entire world. Now, given the efficiency of power distribution, you probably wouldn't want to put it all in one place, but you could easily fit solar panels enough that, even with transmission losses, you could power all of North America in Utah or Texas without anyone noticing. The difficulty is not the generation, it's the storage.

Artificial intelligence has the same relation to intelligence as artificial flowers have to flowers. -- David Parnas