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Comment: wrong way around... (Score 1) 190

by slew (#48569193) Attached to: Fraud Bots Cost Advertisers $6 Billion

What no one was anticipating is that the bots are extremely effective of looking like a high value consumer.

Actually, what is surprising is that these supposed high value customers are not in fact actually bots (instead of essentially being web users programmed to be overconsumers by a history of exposure to saturation advertising and silly enough to click on adverts for stupid things).

Philosophically, when some thing exhibits indistinguishable from another (e.g, a consumer exhibiting behavior indistinguishable from a bot), are these high-value consumers not really acting like "artificial" bots? Because we know these "artificial" bots (aka high-value consumers) aren't actually buying anything, but are simply browsing indiscriminately out of boredom and collecting browser-based exploits from the wild to expand real bot nets in a symbiotic relationship.

On a similar note, people always wondered if the anti-virus companies actually were in cahoots with the virus writers. How do with know the ad platform companies aren't simply promulgating a myth of the ephemeral existence of high-value consumers that want to be identified in a sea of bots by the latest and greatest sophisticated ad platform subscription?

Comment: Re:Are they really that scared? (Score 5, Insightful) 460

by slew (#48532421) Attached to: Why Elon Musk's Batteries Frighten Electric Companies

As I understand it, most of the power company's objections to solar is being forced to buy the power back and subsidize it.

Maintaining the lines to your house is a fixed cost and they are recovering that cost using amortization over periodic billing based on usage. People who go solar are essentially the freeloaders in this system as they pay less of the overhead for the amount of transmission service they receive. This is not unlike the gasoline tax for highway funding debate or numerous other situations.

Governments tend to attempt to make things simpler for consumers by mandating "tariffed" service to avoid "skimming" by the providers. Unfortunately that generally doesn't work as governments generally attempt to use these regulations for subsidizing service for some by burdening others and the companies just get smarter about skimming. Unfortunately, some customers discover the workarounds to freeload for a while (e.g., internet VoIP w/o universal service fund fees, or solar panels with forced power buyback, or electric cars that pay no gas tax). They claim their microeconomic observation about their freeloading is the new economic reality and people should just wake up and smell the coffee.

Unfortunately, when there are too many freeloaders them, then the model just breaks down and need to be fixed so that more people pay full freight. Often, the freeloaders then discover that paying full freight isn't makes the it much less attractive (but at least they got theirs whilst the getting was good). The result is generally simply a different reality than the previous, but generally not much different.

For example, the power company would much rather demand be totally flat. Provisioning for more power is a big capital cost (building power plants, increasing transmission capacity, etc.) that they can only recover by amortization. This is the reality that the power companies lived in the 80's with nuclear power decommissioning. Sadly, we have a big nasty habit of kicking the can down the road on these things...

At least when you collect a welfare check directly from the government you are being honest with yourself...

Comment: Re:Summary is wrong (Score 1) 128

by slew (#48509197) Attached to: Scientists Have Finally Sampled the Most Abundant Material On Earth

Actually, some of it *is* on the Earth; at least some samples are. It's not like they dug a hole to examine it there and say "Sorry, boys, but we gotta leave this thing in the Earth if we're gonna say 'It's in Earth.'"

FWIW, the bridgmanite samples in question (technically a phase of a perovskite crystal structure mineral) does not exist outside the pressure/temperatures which occur *in* the earth which is why samples have never been discovered *on* the earth before (although they certainly have likely existed, no-one has discovered/isolated them before). The interesting thing about this sample is that we didn't have to create the pressure/temperature (apparently 24 gigapascals and 2300 kelvin) in order to form it as these conditions were temporarily created when the meteorite impacted earth.

It would kind of be like if nobody had seen a diamond before, but they were theorized to exist, and someone held up amorphous coal and said it was a sample of diamond because it was just carbon. Of course even though diamonds take somewhat high temperature and pressure to create, it isn't too high, so there are an abundance of diamond fields that exist on the surface of the earth w/o any digging required, so this is kind of a bad example from a scarcity point of view, but from a phase mineral structure point of view, hopefully that "clarifies" it...

The downside is that although this discovery is consistent with the theory of bridgmanite, we still don't have a sample of bridgmanite created in its natural environment *in* the earth, so we still don't know if this is what is actually there. To dredge up the diamond analogy again, there is of course another carbon mineral that is even stronger than cubic diamond called lonsdaleite (aka hexagonal diamond) that can form under higher temperature/pressure conditions like meteorite strikes. So, since this is merely consistent with theory and not an actual sample, apparently, the jury is still out if this sample is representative of bridgmanite or perhaps there's yet another configuration of perovskite that occurs deep inside the earth we haven't figured out yet...

To create another analogy, it's kinda like how we keep on finding all sorts of carbon nano{tube,sheet,fibres} configurations that we haven't discovered before that have unique and potentially useful properties.

Comment: Re:5G will make your phone 5x as heavy (Score 1) 216

by slew (#48499843) Attached to: How the Rollout of 5G Will Change Everything

"5G will be a dramatic overhaul and harmonisation of the radio spectrum," - really? How?

You might be assuming dramatic will be better.
You might also be assuming harmonization will mean everyone should use the same technology.

Perhaps you are misinterpreting this statement? They might be technically correct in their statement yet the technology will be a total fail, no? ;^)

At least in the USA for 4G, there was/is a lot of dramatic overhaul of the network after WiMax's demise and harmonization of the spectrum means the commercial availability of a penta-band phone...

Comment: Re:If and only if (Score 1) 652

by slew (#48460897) Attached to: Two Google Engineers Say Renewables Can't Cure Climate Change

Lower transportation costs, well frankly if those go up, I see a likely benifit regarding more local jobs. I don't see batteries powering those massive container ships, but then again, there is more oil for that kind of shit if it isn't being used in cars, for other power etc.

I don't think you understand the economics of container shipping. First of all, they used the worst possible polluting fuel (aka bunker fuel) because it is unregulated internationally. Secondly, at 15 knots, these ship consume less than 50 tons/day. However at 25 knots, fuel consumption rises to about 300 tons/day. It's all about speed, not the moving with the ships.

(also cars and powerplants can't really use bunker fuel even if it's reprocessed, it won't be economical).

Comment: actually automatic picture caption generator (Score 3, Interesting) 29

by slew (#48430897) Attached to: Google Announces Image Recognition Advance

Not as "advanced" in image recognition as advertised.

Basically they took the output of a common object classifier and instead of just picking the most likely object (which is what a typical object classifier looks for), it leaves in in a form where multiple objects are detected in various parts of the scene. Then they train a neural network to create captions (by giving it training pictures with associated captions).

According to the paper, it sometimes apparently generates a reasonable description. Other times it reads in picture of a street sign covered with stickers and emits a caption like "refrigerator filled with lots of food and drink".

Actually the most interesting thing about it is the LSTM-based Sentence Generator that is used to generate the caption from the objects. LSTM's are notoriously hard to train and they apparently they borrow some results from language translation techniques to attempt to form intelligible sentences.

This is all very googly-researchy in that they want to see what the limits of pure data driven machine learning are (w/o human tuning). This is not a however much of an advance in image recognition as it is an advance in the language for caption construction.

Comment: Re:Nuclear Test Ban? (Score 1) 523

by slew (#48428915) Attached to: What Would Have Happened If Philae Were Nuclear Powered?

FWIW, NASA has used radio-isotope-thermoelectric generators (aka RTG) in several space missions. RTGs are basically nuclear "batteries". The most high-profile have been Voyager, Cassini, and Curiosity...

The radio-isotopes inside RTGs give off radiation, but it's generally pretty low and all the radio-active parts are sealed inside the "battery" so that even if they blow up, the battery is generally still intact.

The problem with using batteries for propulsion is efficiency. These batteries are heavy vs the amount of power (energy over a short period of time) they can deliver, so you need to use a different way of extracting the energy from the radioactive material which generally is less safe (and more "bomb-like"). That is not allowed.

Thus the RTGs are only used to power the electrical sub-systems and the waste heat is used to keep the electronics at a reasonable temperature in a cold depths of space... kinda like a big battery...

Unfortunately, these RTGs are hard to come by (they are generally powered by a radioactive isotope of plutonium), and the European Space Agency (which launched the probe) doesn't have the ability to make them. Nasa has some, but apparently none were usable for this mission (e.g., if you need AAA and you have only C batteries, you are kinda SOL)

Comment: Re:Mass (Score 1) 523

by slew (#48428723) Attached to: What Would Have Happened If Philae Were Nuclear Powered?

where as the panels afford the craft the possibility of functioning indefinitely...

Except for the small fact that they don't expect the probe to operate as it approaches the sun (it's a comet they are on and they tend to "activate" when they approach the sun).

Had you been talking about a probe set to go well away from the sun then absolutely and pu-238 power plant would be a great idea.

And if they actually did expect the probe to survive the approach to the sun, as it is a comet, it would have definitely gone far-far away from the sun...

AFAIK, one of the main reasons they didn't use and RTG is that no usable ones were available from NASA and the ESA didn't yet have the expertise to make them themselves. Not to say that they still wouldn't have gone solar because of other mission parameters (e.g., mass), but the reasons you give don't really add up.

FWIW, once RTGs are assembled, you don't get to "hibernate" them, they start to decay immediately (kind of like a battery). If you don't have the capability to make them yourself, there might be one on the shelf you can buy from someone else, but it's probably not designed with your power budget in mind and it still has it's original weight, but the amount of power it will put out is reduced by sitting on the shelf. It took 10 years to get to the comet, so that's really puts a lot of constraints on using a pre-existing RTG, perhaps too many for the mission, but if they had the technically ability to make a custom one that matched the mission criteria, I'd bet they would have strongly considered it.

Comment: Re:Ignorant Article (Score 1) 523

by slew (#48428601) Attached to: What Would Have Happened If Philae Were Nuclear Powered?

The fuel is consumed faster than its halflife because of subcritical chainreactions. The amount of chainreactions, and thus the energy output, can be controlled by absorbing neutrons.
See http://en.wikipedia.org/wiki/C...

Sub-critical chain reactions in RTG are pretty much minimal. The mass and configuration of the radioactive source is selected so that it is essentially a textbook half-life source (from fission cross-section).

The whole point of an RTG is that it doesn't need things like control rods or have failure modes associated with moving parts. Unfortunately, they are generally thermodynamically less efficient generating electricity/energy (relative to waste heat). They also tend to use very heavy encasements for launch safety reasons reducing their weight-to-power efficiency vs solar.

On the more leading edge of RTG research is combining a thermo-electric (e.g., seebeck style) and photo-electric to convert more of the infrared energy that is currently wasted in an RTG to useable electricity. There is also some research into finding so-called high zT materials (ones that have higher conversion efficiency), but results so far have been disappointing (this might be because this research is more niche and thus less lucrative than high temperature superconductors which has occupied researchers for a while). Sadly RTG have very little commercial or military value (Pu is hard to obtain in scale and the it's a niche market to begin with and cannot get bigger) and as a result likely aren't going to get much more attention from researchers.

Comment: Re:and that means it doesn't cost any more? (Score 1) 231

by slew (#48407297) Attached to: The Dutch Village Where Everyone Has Dementia

Easy though it is to harp at the executive pay, it is largely irrelevant to the cost of the final product...

As a first order effect, no, but since executive pay is often tied to the company profitability (either through stock options or bonus plans, or both), a CEO has quite a bit of incentive to massively increase the profitability of the enterprise so he/she (okay, I think they are all he) will reap the percentage rewards (along with all the other stock holders) without regard to the cost of the customers bottom line. This second order effect is simply a natural consequence of how things are set up...

If you think about it, this second order effect would likely a bigger effect than the first order effect... ;^)

Oh yeah, a typical pharma company might actually really need to make insane profit on the home run products in order to cover up for all the crash and burn products they will probably produce, but that doesn't take away from the first argument...

Comment: Re:Anybody familiar with the manufacturing side? (Score 4, Informative) 111

by slew (#48389411) Attached to: An Applied Investigation Into Graphics Card Coil Whine

I understand that high-frequency magnetics are at risk of physical oscillation(the detailed math is right over my head; but all it takes is one part of the part attracting or repelling another part of the part, at least under some input waveforms, and you'll potentially see movement, which easily enough turns to sound); but the seemingly obvious solution is just to pot the magnetics in an adequately thermally conductive epoxy or other encapsulant.

Does anybody know if that just adds too much cost, without performance benefit, and so gets cut during the BOM penny pinching? Do potting compounds have properties that degrade the performance or efficiency of common magnetics? Why is it that, if coil whine is an issue, they aren't just dipping the things in epoxy and calling it a day?

Unfortunately mechanical damping of the inductor vibration isn't as effective as simply reducing the amplitude of driving frequency in the audio bands. Remember this is a sub-harmonic that is being excited by a non-linear coupling to the audio frequency. Basically the energy in a higher frequency is being converted into a lower audible mechanical frequency.

Theoretically, simply changing the mass of the physical oscillation (e.g. cementing it to something heavier) only slightly modifies the frequency of the oscillation (potentially creating more audible noise) and it still doesn't change the energy much. Viscous damping of the mechanical frequency might help a little bit more. Unfortunately, in practice, surrounding things like solder joints in potting compounds is risky as they have a different thermal expansion coefficients and it can cause additional mechanical stress (resulting in reduced mechanical reliability).

In the end, mechanical means are still not going to be as effective as changing the circuit to reduce the amount of switching energy frequencies which are coupled to the audio frequency bands. Probably even from a total system cost point of view...

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