Anytime someone brought in a kid suffering from a disease that could have been prevented by vaccination, I would first ask whether the parent was brain dead.

-jcr

Not as useless as bitching about it, kid.

-jcr

Sounds about right. With all the MS employees looking to jump ship, I can't see why anyone who wants to hire a Windoze developer would spring for a ticket to interview a candidate from a different city.

-jcr

No, Bitcoin isn't "pegged" to any and all currencies, it's free-floating. Rather too free floating and volatile as the case may be.

The problem with Bitcoin isn't the absence of a central issuer, but right now the problem with Bitcoin is its extreme volatility. At the moment it's almost useless as a currency and it's being used as an instrument of speculation. It's far too volatile for any merchant (perhaps except the black market) to take seriously since it's value relative to all other currencies swings so wildly and so quickly and you have to convert BTC into your local currency to be able to use any funds transferred to you for the mundane things in life like buying food, electricity, housing etc. If I want to sell a thing worth about US$1200 in BTC, if I sold it at 9am today for 1BTC and waited a whole 15 minutes to convert this to USD, in the intervening 15 minutes I would have lost around $300 because of a wild swing in its value that happened over a period of just a couple of minutes.

Certainly in the Gulf of Mexico, the various platforms and structures provide a pretty rich environment for marine life. The best fishing spots are all near the various platforms since the underwater parts of their structures provide places for various plants and animals to make their homes (and thus attracting the fish that feed of this). I would imagine the mooring points for this barge will do the same.

Of course it all goes horribly wrong for this environment if there is a spill.

Technically, it's a barge.

-jcr

Then they ought to be interstate OR defense highways. Since interstate = 0 (always, in Hawaii) and defense = 1, interstate AND defense will evaluate to 0. Therefore it's still odd they are called interstates.

They work perfectly well with the lid closed. My MacBook Pro spends about 50% of its life with its lid closed. The "rats nest" of cables is just one mini-DisplayPort cable, one USB cable and one power cable, since my display works as a USB hub so everything else gets plugged into the display.

It works perfectly with the lid closed (it's a very recent machine with OS X Mavericks on it). Indeed the latest version of OSX improved its "working with the lid closed" ability - when moving from lid open and on the move to lid closed and plugged into the monitor/keyboard, there's none of the awkward five seconds of display resizing that used to happen.

It's a lot better than nothing. Let's assume the artist spent 100 hours of work just on that specific song and recording. 2336 euro then works out at 23 euro per hour pay, which is actually not bad, and so far we're only listing four months. There will be plays in July, August, September, October and so on, so the final hourly rate for making that song is probably going to be 50 or 60 euro/hr. That's a pretty good hourly rate for doing something that is basically fun.

So we can discuss it.

Weather does affect range (wind always reduces it, unless you get a tailwind in both directions). The maximum airspeed of anything that flies has a limit. However rotor powered aircraft don't work as simply as you suggest. Once they exceed a certain speed (which is quite a low speed) they gain translational lift, and don't need to 'tilt' nearly as much as you would expect. My model T-Rex 500 model helicopter will do about 60 mph with very little visible forward tilt. A T-Rex 700 with an aerodynamic body will do about 80 mph without much of a problem. The limit to this helicopter's airspeed is not how much it must tilt, but retreating blade stall, when the angle of attack of the retreating blade must be so high that it exceeds its critical angle of attack. In a single rotor helicopter, the onset of retreating blade stall means that the half of the rotor disc which is retreating makes less lift than the half of the rotor disc where the blades are advancing (in most helicopters, this causes them to pitch up due to gyroscopic precession, so unless the pilot aggravates the condition by pushing the cyclic further forward, it becomes kind of self-correcting). If it goes too far and the retreating blade actually stalls the helicopter will start to roll and depart from controlled flight. With a multicopter you won't get the departure from controlled flight but you will have a severe loss of lift. This happens way WAY before the tilt angle gets great enough to significantly affect lift just due to pure thrust vector issues.

If you can only target high density areas of cities, you're already screwed, because for the forseeable future an octocopter isn't going to be able to deliver to a multi-occupancy building. It would need outdoor infrastructure (a multi item mailbox outdoors with a landing pad, in areas where all the space is already used up) since for many multi occupancy buildings you have to go inside the building just to deliver the mail. Without a lot of additional infrastructure (who's going to pay for it? Amazon?) drone delivery is only going to work where it's least suited - low density suburbs or rural areas which will likely be a long distance from the distribution centres.

I agree that it's impractical in the forseeable future (battery technology will need significant improvements - no one will tolerate a gas-powered version because it'll sound like a flying chainsaw; sense-and-avoid will have to improve very significantly to avoid collisions with birds, powerlines, people etc, failsafes will have to be better than "just shut the motors down" because that could drop the drone on a person or a moving vehicle and cause injury and/or damage. These are all hard problems that won't likely get fixed in the timeframe Bezos quotes. So I agree it's just a publicity stunt.

However, n-copters (n>=1) are not necessarily good-weather toys only. Even fixed-pitch types like the AR drone can withstand pretty gusty winds outdoors. You can also make a small something-copter VERY good in very gusty winds if it has collective pitch control on its rotors. Collective pitch rotor systems can react extremely fast. I have a number of RC helicopters, and even my tiny T-Rex 250 could be flown in 20 mph gusting winds because it was collective pitch (a fixed pitch heli would be lost with that much wind). I've flown my T-Rex 600 quite happily in gusty winds over 30 mph - I had to give up not because the heli was hard to fly, but the wind was blowing water out the tear ducts of my eyes and making the helicopter too hard to see.

The main problem with a drone (of any number of rotors) would have that was sufficiently powerful to lift a 5 lb package AND deal with potentially strong gusting winds is that it'll also be very powerful too. A blade collision with a person would likely lead to a pretty serious injury; the Amazon drone would need to be at least as powerful as a T-Rex 600, and model helicopters of this power have already resulted in deaths.

You didn't read the last line of my post, did you?

-jcr