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Comment So, like all other rewards programmes? (Score 3, Interesting) 75

In New Zealand we've got Flybuys.
For a retailer to be part of the programme, their POS system needs to send every item on your receipt to Flybuys. They don't just get "customer A spent $X at retailer Y". They get each product you bought, how much you paid for it, if it was on sale and what the payment method was.

It lets them do things like see the last time you bought a pregnancy test and a few months later, start putting specials for baby products in the next email you get sent by them on behalf of your local supermarket. Or if you buy a particular brand of razor, they might tell you about specials for blade refills.

In exchange for all that information, you get to spend reward points on selected products.

Comment Re:Summary of advantages: (Score 1) 91

full control over the encryption software

- performance nearly identical through either hardware-enabled encryption (AES...),

Do you see what you did there?

- performance nearly identical through (supposedly) hardware encryption.

Unless your system can multi-task and uses the hardware encryption resources for other processes. Like a web server that's also doing SSL/TLS.

Comment Re: How is this news. (Score 1) 91

It's a bit worse than that.

You can't write a block without erasing it first.
Most NAND chips don't let you erase a single block (eg: 4k or 8k), you have to erase a group of them (eg: 512k)
To write one block that already contains data, you need to read all blocks in the group first, erase them all and write out all blocks.

Worse case, to write 1 byte, you need to read in 512k, erase it all and write back all 512k. Normal case, you attempt to write entire blocks at a time and the wear leveling algorithm picks an already erased block to write to and leaves the original block intact (and marks it as unused)

Comment Re:And here I was (Score 1) 260

The 10 ohm series resistor is to simulate loss in the wires. It's not part of the system being tested, it's part of the test setup.
In the real world an inverter has to work with a non-ideal power supply. All real power supplies have output impedance.

Input ripple is the AC component of the load. The drop across the resistor in response to the load is DC.

Comment Re:Receiver must be nuke proof... (Score 1) 115

HP ink jet printer heads heat the ink up to temperatures 7 times hotter than the the sun. It doesn't end up burning a hole in the earth's crust though, since it only lasts 2 microseconds.
http://h20423.www2.hp.com/prog...

It doesn't take a lot of energy to heat something up really fast as long as it's really low mass, like air.
In fact, the quicker you heat something up the less energy is required, since there is less time for the heat to dissipate during the heating process.

Comment Re:I've heard this one... (Score 1) 260

Given that this would be upwards of 2000x higher density than a lithium battery, does that mean a 60Wh laptop battery has the explosive capacity of half a stick of TNT?

60Wh = 216kJ
0.19kg stick of TNT = 532kJ

The 65L of petrol in my car stores 2340MJ and is equivalent to nearly a ton of TNT.

TL;DR: Comparing batteries to explosives is a bad idea. They're completely different. A battery isn't going to explode, it's going to burn.

The difference between burning petrol and exploding petrol is your car running perfectly fine and a conrod putting a hole in the side of your engine block.

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