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Comment Re:This is why you call your bank before tourism (Score 1) 345

The detection algorithms assume two purchases at the same store within minutes of each other are usually a sign of double-dipping or card cloning at the store. Physical presence at a store normally results in a single transaction, not multiple, for most shoppers.

Dealing with this in an online store can be difficult as multiple purchases are normal. Amazon's Kindle store handles this by delaying some of the transactions if they would appear too similar. I just bought two ebooks via the Kindle for $10.00. The first went through instantly, the second came through nearly six hours later. This is an interesting way to do things and I think Amazon only does it with the Kindle store because they can remove the book if the transaction fails later.

Comment Re:Great. (Score 1) 163

To me it makes sense when coupled with the assumption that Weyland hired the crew to be susceptible to bribery and to be easily disposable. The mission wasn't supposed to be scientific, just to appear to be just scientific enough that Shaw and Holloway wouldn't be suspicious about the real nature mission.

If Weyland had hired top xeno-biologists, they would have canned the exploration long before they got anywhere near what Weyland needed. Having someone who is there for the cash, basically a mercenary with just enough biological skills to pass muster, but not to react as a research scientist would, gets Weyland to that goal. Same for the rest of the team, and that scene with electrocuting the head highlights that they hired third or fourth-rate scientifically skilled mercenaries.

Ridley Scott and the rest of the Alien series set the groundwork for this process. Weyland-Yutani routinely had ill-equipped, non-specialist groups fiddling with alien technology, relying on their mercenary nature to do stupid yet profitable things.

  • The crew of the Nostromo was a long-distance trucking crew.
  • The family sent to investigate the crashed ship in Aliens, and the entire colony team, was in it for a cash reward.
  • Carter Burke and the real Bishop are the same.
  • The entire research station crew, including the military, in Resurrection also.

It might have been a bit too much in-your-face in Prometheus compared to the early Alien movies, but the way Weyland carried out the mission was in perfect conformity with their "later" missions in the Aliens series. Hell, it explains why the Nostromo of all ships was diverted to investigate the signal.

Comment Re:Why human in the loop? (Score 1) 104

How would a computer do a task like this. Aircraft is on final approach, 300m from the end of the runway when it drops suddenly and crashes over the final row of landing lights and skids to a halt on the hit point of the runway? How does the computer detect that, determine that it is an accident and then respond.

Sometimes you just need humans who are watching what is going on and capable of instant recognition of what is happening.

Comment Re:Why start now? (Score 1) 124

There may be 10000 bird strikes a year without causing a crash, but it doesn't mean those strikes are harmless. AVHerald has three bird strike incidents listed for the last calendar week that have results in the aircraft returning to the airport and then being grounded for 2-3 days while repairs to radomes and other panels are carried out. That's repair costs and lost revenue for the airline because of a relatively unavoidable incident.

Incurring the same repair costs and lost revenue for a completely preventable incident would seriously piss off most beancounters and that's why the FAA regulates RC aircraft near commercial flight paths. It's not just about a crash, it's about the damage and costs of non-crash incidents as well.

Comment Re:Probably 15.0 kW, not 150 (Score 1) 106

You're all falling into the trap of average daily power usage. The heliostat needs to provide the peak power draw, not the average power draw of a house.

I'm a South African and while my 3 person house averages 700W power consumption over a 24 hour period, my peak is close to 10kW if I've got the stove, water heater and kettle going at the same time. That happens regularly in the early evening or mornings. And yes, we have electric stoves and water heaters because we don't have a gas infrastructure like Europe or North America.

Our electricity rates per kWh seem to be comparable to the US rates, 10 US cents to 14 US cents per kWh for my city's inclined tariffs. But solar installation costs are high, a 10kW installation with batteries to hold overnight can be around $25000 and the batteries will have to be replaced after 6-9 years at around $8000. My house uses roughly 1000 kWh a month for a bill of $110. So the capital cost would pay off over 19 years, but after a maximum of 9 years, I'd add another 6 years to that. And for the average working and middle class South African, $25000 as a capital expense is a harsh layout.

Comment Re:Cooling? (Score 1) 90

Even if you ignore the thermally conductive epoxies somebody else mentioned, simple.

Before you resin-pot the boards, you put a water-cooling heat exchanger on the chip and pipe the coolant to a radiator outside the epoxy block. Or if the thermal profile is low enough, you can do it with passive heat pipes like those inside my laptop.

Comment Re:FYI radio astronomers: Beware dodgy microwave o (Score 4, Interesting) 27

I've met a couple of the chaps working on the South African SKA site, very interesting characters to say the least.

One of the things that stuck in my mind was how sensitve the receivers are, if they unpack them and a cell phone is on in the direction of the receiver horn, they'll blow the circuits instantly.

They also have controlled perimeters where phones are locked away and even airplane transponders are switched off before they cross the perimeter. Ridiculously sensitive stuff.

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