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Comment Re:"new" as in "sold since several years"? (Score 1) 86

Since I install solar for a living I was curious, and I looked into this system a little bit. There are a number of problems here:

* multicrystalline silicon requires more energy to manufacture, out of proportion to the increase in production efficiency
* Germany, despite having very generous incentives, is actually about as bad in terms of solar resource potential as Alaska
* the modules used should be more efficient than 10%, even considering the semi-translucent design
* the balance of system components could be a lot more efficient than 86%: this is an area that has improved considerably in recent years
* the expected losses due to shading (15%) seem a little high considering the height of the building
* yes, you do take a significant hit installing in a vertical orientation

Add it all up and it makes for a system that should never have gone in. But these types of building integrated designs are worthwhile when done properly.

Typically, the Energy Return on Investment is around 3 or 4 years and it should be no more than about 10 years for an installation like this one.

Comment Re:BRAAIINNNNNNNS (Score 2) 179

The EU's Human Brain Project has an estimate of 1000 times the current fastest supercomputer (probably written about a year ago), so maybe around an exaflop.

"Today, simulating a single neuron requires the full power of a laptop computer. But the brain has billions of neurons and simulating all them simultaneously is a huge challenge. To get round this problem, the project will develop novel techniques of multi-level simulation in which only groups of neurons that are highly active are simulated in detail. But even in this way, simulating the complete human brain will require a computer a thousand times more powerful than the most powerful machine available today." (link)

That's 10 doublings, so if Moore's Law holds up this level of capability should be roughly 20 years away. I think it's interesting to note that this also suggests the feature size will halve 5 times to right around 1 nm: atomic scale. My rough understanding is that no matter what you may have heard from semiconductor physicists we are currently pretty clueless as to what, if anything, is going to drive the progress of Moore's Law beyond about 10 nm.

Comment Re:The article is kind of pathetic (Score 1) 171

Since both of you seem to be in Hong Kong, how about one of you get hold of one of these and post some better photos. Then we could put this to rest for good.

The photos are so bad it is hard to tell, but I'm leaning toward this story being true. Mainly because of that base-loaded whip antenna. The odd shaped PCB on the left seems to be the actual RFID component (with a battery assist). You can make out what looks like a PCB trace antenna toward the bottom (in sort of a G shape), and, if that's indeed what it is, you have to wonder why this device needs two antennas.

Comment We live in the boonies (Score 1) 81

"The growing consensus is that the Milky Way has a central bar with two main arms, called the Perseus Arm, which passes with a few kiloparsecs of the Sun, and the Scutum-Centaurus Arm. (The other arms are now thought to be minor structures made up largely of gas.)"

As a resident of the Orion Spur, I resent that statement.

Comment Re:No legitimate use (Score 1) 374

Sure, I can think of plenty. "Imminent eruption of Yellowstone Caldera is predicted: ash set to spread over large area and disrupt food supplies." "Russia just launched its nukes: remain inside and get your fire extinguishers ready." "Cubs win world series: stay on the lookout for flying pigs." Okay, maybe not that last one.

Besides, I think that is actually the point of having a separate chip. If you use a different channel for these alerts, AND if the system is implemented well, you could have the electric grid and phone networks wiped out and all the cell phones with battery power left will still get the alerts.

Comment Re:Rainbow Dash (Score 1) 141

This might be true, technically speaking, if storing the information that results from each calculation required work to be done (for instance, you have to do work to change the magnetic moment of the grains in a hard drive platter). But in the CPU this information is just represented with a potential.

Comment Some details from the paper (Score 2) 129

"Although there are a multitude of variations in synapses, we have modeled a typical cortical synapse. Action potentials, the signals from other neurons that arrive at the synapses are about a millisecond in duration and about 100 mV in amplitude. Under certain conditions, the synapse responds with an output potential of around 5-10 mV that lasts around 10 ms. Thus the synapse slows and spreads the effect of the action potential, synchronizing its effect with other action potentials, since not all action potentials arriving at the postsynaptic neuron will arrive simultaneously...The resulting postsynaptic potentials produced by many synapses combine to create enough potential (voltage) for the postsynaptic neuron to generate an action potential and fire."

I think the same thing could be achieved with just an RC filter. If I'm following this correctly, the difference here is a "demonstrated variation in synaptic strength, a key neural mechanism associated with memory and learning." Things will really start to get interesting when something like this circuit can be made that is also capable of amplification. That would be a complete artificial neuron.

http://ieeexplore.ieee.org/xpl/freeabs_all.jsp?arnumber=5754178

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