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Comment: Electric car batteries (Score 4, Insightful) 87

by Donwulff (#46504957) Attached to: EU Project Aims To Switch Data Centers To Second Hand Car Batteries

If anyone remains confused after the summary as I was, just to clarify they're discussing electric car battery packs. Using them to power datacenters during peak eectricity demand, and charing them back up during low electricity demand would indeed be useful. I'm quite suspicious about their degradation expectations, however.
Being stationary installations well designed datacenters could often use more efficient and environmentally friendly options, like flywheels or thermal storage. There would perhaps be more demand and practical use for such battery packs as backup power during power outages, as those kind of emergency batteries will be required in any case.
Hopefully it is possible to compromise between these two, for example by using 75% of the battery capacity for shifting power-demand to off-peak hours, and reserving 25% for backup power in case there's power-outage before the packs have been re-charged.

Comment: Re:who writes these headlines? (Score 1) 126

by Donwulff (#46497657) Attached to: Solar-Powered Toilet Torches Waste For Public Health

That was the way I read it until I took in the summary, too. I was really disappointed when I grasped the real meaning, because the original reading made a whole lot more sense. At our summer villa we used to use solar-charged "lanterns" in the dark, such as going to the outhouse after sun had set. These are obviously "toilet torches". I'm not sure why you would even consider them for public health, but they'd probably end up doing very little for it, beyond preventing some campers or outhouse-users from stumbling in the dark, so I'd have to wholeheartedly concur with the headline. Still I'd consider it another headlining failure...

Comment: Re:Gun + BC client = $1,000,000,000 (Score 1) 390

by Donwulff (#46421321) Attached to: Bitcoin Inventor Satoshi Nakamoto Outed By Newsweek

Two REAL things: 1) The D-Wave computers are not true quantum computers and can't be used for that, and so far it's not even been shown D-Wave quantum computers exhibit quantum nature at all, and 2) Even a true quantum computer would simply make the hashing faster, which in turn would lead the Bitcoin network to adjust its difficulty higher, for no net gain.
There are numerous reasons to criticize Bitcoins, but "Think about the D-Wave quantum computers!" is NOT one of them. Actually ASIC-miners are lot more realistic and imminent threat that has already materialized, leading their owners to adopting measures and treaties to try to convince Bitcoin community they would not take advantage of it - they're the ones with most to lose, after all.

Comment: Re:mAh is only half the equation (Score 1) 131

by Donwulff (#46394721) Attached to: Sulfur Polymers Could Enable Long-Lasting, High-Capacity Batteries

Well, amount of energy per mass. But amount of energy per volume will come a close second, and unless they have unlimited charge cycles with no degradation, energy per dollar will be sharing that close second position. Charge efficiency is probably around third most important, and whether it's prone to exploding randomly in a fiery conflagration is up high there as well. In short, almost anything else than what was actually provided in the summary :)

Comment: Re:Unmanned car ? (Score 1) 63

by Donwulff (#43311861) Attached to: Google Releases Street View Images From Fukushima Ghost Town

I'm curious why you claim that, although I probably shouldn't expect much as your message boils down to an ad-hominem without even telling what you object to. Sieverts are weighted by biological effectiveness of the particles, so that when comparing committed doses from different sources ("nature of the exposure") they are intended to be comparable. Whether scientists have been successful in making them comparable is a topic that's perhaps more suited elsewhere than web-site discussion trying to find comparison points for dose rate, but that's certainly the intended purpose of Sieverts.

The wording on the "10mSv/yr average, 20mSv/yr max" claim makes it sound like it is committed dose. As I pointed earlier I'm aware geiger-counters don't measure Sieverts, at most they will show air gamma-ray dose at midpoint of body if calibrated correctly. In general this would be in ballpark of the minimum committed dose. If they ingest, inhale or touch anything, it'll be higher of course. In a car or cleaned up house it'll likely be lower due to distance and shielding. I've brought up the geiger-counter readings only as a means to show the average dose can't possibly be as low as 10mSv/yr, and the maximum certainly isn't 20mSv/yr.

However the Wikipedia quote on smoking is misleading if not outright incorrect, as I checked the original sources. The wording indicates it's whole body (effective) dose, but checking out the original source turns out it's only bronchial epithelial dose, so that is not really comparable to the others.

Comment: Re:Sorry but you are half correct (Score 1) 63

by Donwulff (#43310931) Attached to: Google Releases Street View Images From Fukushima Ghost Town

It's clever to switch to claiming "average" instead of the indefensible "highest", as to prove average one has to go through every square inch... On maps Namie seems to usually be lumped up in the >30mSv/yr range (which ranges ranges all the way up to 1.6Sv/yr on the NPP). 10 mSv/yr would equate to 1.1 microSievers/h and it's actually hard to find outdoors areas that low in Namie town. On Namie town's own site (if you can read Japanese) decontaminated areas are listed as up to 10microSv/h (87.6mSv/yr) - they're actually lower than normal due to snow cover. According to the highest monitoring post measurement within Namie prefecture is currently 9.2 microSv/h. The measuring posts showing lower than actual values is well documented however, probably owing to decontamination and shielding of the monitoring posts, though they're probably within that range.

It's hard to get there with a counter and measure for yourself, the government has taken a hard line on that and uninvited visitors face penalty of up to month in prison, so most measurements are just outside the mandatory evacuation zone. That's right, there's nobody living there, just empty buildings so they do have a legitimate worry about guarding property there. The dose rates before people were evacuated, back in 2011 (it's been over two years now) were much higher, up to 50mSv before evacuation (according to WHO). Radiologically hottest isotopes have decayed and the rest dispersed across the world since then, though.

For the Youtubers, there's always for example. Person in that video at end of last year is measuring 13.05 microSv/h at waist height. Bringing the geiger-counter to fallen leave on ground, the dose rate jumps to 42.69 microSv/h. Given 365*24 hours in a year those come to 114 mSv/yr and 374mSv/yr respectively. And that's actually 28km from NPP within Namie prefecture, not 8km - but fallout can be spotty. But there's been no concerted effort to find the highest spot, just measurements here and there.

Finally... Fukushima will be good for us and telling people to stay out of mandatory fallout evacuation zone is unscientific fear-mongering? Ah, I see, you're just trolling, well carry on.

Comment: Re:Unmanned car ? (Score 3, Informative) 63

by Donwulff (#43310357) Attached to: Google Releases Street View Images From Fukushima Ghost Town

About that, actually studies have quite consistently found airline crew annual exposure is around 2mSv/yr, see for example flights.html. 20mSV is the absolute maximum annual dose that "should" be allowed for airline crew, while studies have found 20mSv is typical lifetime dose for airline crew.

There's better comparisons to put the dose rate in perspective though - for example, "Smoking an average of 1.5 packs per day gives a radiation dose of 60-160 mSv/year" (Wikipedia) while a CT-scan can give around 20mSv per examination - classified as "moderate" risk of developing cancer, as in 1 in 1000 to 1 in 500.

In this context of course none of this hardly matters - the Google driver isn't going to be spending an year there, and they're certainly not going to "internalize" most of that radiation. But it's very valid point for the prospect of people returning to Namie - the dose rates measured are taken at around waist height height where alpha and beta rays hardly even reach, indicating only external gamma ray dose. Those dose rates tell nothing about people who live, bathe and breathe in that isotope-soup. But currently, nobody lives in Namie and it's not know when, if ever, that can even be considered.

Comment: Re:Unmanned car ? (Score 2) 63

by Donwulff (#43310273) Attached to: Google Releases Street View Images From Fukushima Ghost Town

As everybody knows, Wikipedia is the end and be all of any scientific knowledge, so let's have a fact-check:

"The highest dose". Wikipedia to the rescue! "On 6 May 2012 it became known that according to documents of the municipal education board reports submitted by each school in Fukushima prefecture in April at least 14 elementary schools, 7 junior high and 5 nursery schools so called "hot spots" existed, where the radiation exposure was more than 3.8 microsieverts per hour, resulting in an annual cummulative dose above 20 millisieverts." Those schools are quite further away from the NPP than Namie, and the reason their dose rate is known at all is they were required to be measured. So we can say with certainty that expected highest annual doses exceed 20mSv/yr, in fact in Namie it's likely to be significantly higher.

"1/5th of the dose". From Wikipedia, "The linear no-threshold model (LNT) hypothesis is accepted by the International Commission on Radiological Protection (ICRP) and regulators around the world." They note that there is some controversy, but over the linear part, not the no-threshold part. As in any scientific subject, one can always find a study-du-jour to challenge any widely held belief, but the no-threshold model seems to have become something of a consensus, except among those who seek to dismiss dangers of radiation.

Otherwise I generally agree, in particular the Google photographer is not going to be spending a year there, and I would wager they have the car windows tightly shut and air-conditioning off "just in case". With those precautions and a "decontamination" with e.g. firehoses on the checkpoint one could easily brave even higher contaminated areas. They may also change drivers regularly just to be safe - after all, elsewhere it's noted "Swathed in white protective masks and suits, residents are bused into the zone on rare occasions to retrieve valuables and check on their homes. The trips are brief—roughly two to three hours—to minimize radiation exposure."

Comment: Re:The scary part... (Score 2) 270

by Donwulff (#42874241) Attached to: North Korea Conducts Third Nuclear Test

I was really confused where the claim "4 times" came from, I'm guessing now, but let it be said the original claim is based on so many erroneous assumptions it really doesn't matter.

First of all, "Richter scale" has not been used in most of the world for decades. Everybody uses Moment Magnitude scale nowadays, and the quoted values are the Moment Magnitudes. Also, USGS almost immediately re-classified the latest as M5.1 as more information came in from seismic stations.

The Moment Magnitude scale is still logarithmic, with a base of 10. This means the difference between 4.5 and 5.1 is 10^(5.1-4.5). This is 4.0, coincidentally. However, this is ONLY the difference between the Moment Magnitudes. This is a measure related to the amplitude of the waves. The difference in energy (mechanical work) required for said amplitude change is 10^1.5 or about 32 per magnitude.

Thus it follows the comparative difference in energy released is 10^(1.5*(5.1-4.5)). This is 7.9. As others have pointed out, the earthquake is not neccessarily directly equivalent to the yield of the bomb, however in this case we know the test was seemingly conducted on same test-range. We can also hypothesize the test conditions, or coupling to the eart, have been similar in nature. Thus it would not be completely unreasonable to assume this is about 8 times as big as the 4.5 one.

This means North Korea's latest test was equivalent to maybe $2,400,000 dollars worth of Ammonium Nitrate, or about 19.2 kilotons if you want to keep it to "normal" units and CTBT estimations. This would put it between the levels of Hiroshima's Little Boy and Nagasaki's Fat Man. Western nuclear missiles have been counter in 100's of kilotons, per nuclear warhead. South Korea is currently calling it at 6 to 7 kilotons. Of course, nuclear test yield doesn't in any way relate to what is the largest they can make.

Comment: Re:Picking nits (Score 1) 148

Actually I would like to nit picks with the professor in that the starting conditions of the flight are specifically not stated. As the professor himself says, "Randall doesn’t explicitly state the starting conditions for the Cessna, so let me guess that it starts off 1 km above the surface with a speed of 60 m/s." With different values for the starting speed, different results will be obtained. In the graph where he shows Randall's and his calculated trajectories in one, he's specifically not "provide more accurate paths", but is in essence pointing and laughing at "Look how ridiculously off Randall's math is".

But he's WRONG. Naturally they're both ridiculously, utterly wrong because I'm so much smarter than either of them. It's obvious even to a child the starting speed should be 0m/s, and thus the trajectory for all of the cases without atmosphere will resemble the trajectory of a rock falling from the sky. (Although, are we drawing the trajectory in reference to the planetoids surface, in reference to the planes starting point, or perhaps in distant Earth's reference frame? In each case the trajectory will be different, and as the professor himself notes, "Oh – you might notice that I have not looked at the radius of curvature for the planets. You can do that for a homework assignment if you wish.")

Comment: Re:Surprise (Score 1) 468

by Donwulff (#42709087) Attached to: Norwegian Study: Global Warming Less Severe Than Feared

Perhaps, but when the government of the third largest oil producer in the world finds out against scientific consenus that consuming oil is, in fact, good for you it should perhaps, just perhaps, be approached with a little bit of scepticism rather than touted as incontrovable evidence.
And in fact, the claim that global warming has stopped has been refuted again and again in the past. There is far too much noise in climate to make such a determination based on only a decade of data. At some point we'll reach a point where such a determination could be made, but my prediction is the claim will just morph to the form of "But global warming stopped in 2010!".
Further, many claims like the Norweigian ones aren't really claiming what most global-warming deniers seem to think they are. Bloomberg quotes the researchers; “The Earth’s mean temperature rose sharply during the 1990s,” said Terje Berntsen, a professor at the University of Oslo who worked on the study. “This may have caused us to overestimate climate sensitivity.”
In other words, they're saying the science is fine and the predictions were correct until 1998, but then for a reason they don't know and can't even guess, global warming suddenly stopped happening. And they're counting on this condition to last indefinitely, or at least for their lifetime, so people don't have to cut down on buring fossil fuels until they run out. But basically, they're only squabbling about the rate of global warming.

Comment: Re:Apple summed up in one breath! (Score 1) 330

by Donwulff (#42699493) Attached to: Steve Jobs Movie Clip Historically Inaccurate, Says Woz

While making fun of a no-talent hack like Jobs is all fun and games until someone puts out an eye, I'll have to note that Woz's phrase does not parse out without substantial background information. In particular, not being a computer history major I do not know what he means by "computer I'd given away", but guessing from the current movements I'd suppose he means he gave out for free the schematics to build a computer.
Given that today it's not unheard of to see even something like 100-fold increase from basic Bill of Materials costs to some finished low-volume products, and that the computer club members would have been well aware of the materials cost, this sounds like classic enterpreneurship and possibly a good deal for all people involved as well. Also, I fail to see what it has to really do with the context of social impact and operating systems, other than to illustrate the already widely touted point that Jobs was more of a marketer than visionary inventor.
He might as well have said "His ideas had more to do with making money than changing the world, but by making money he incidentally changed the world". And that, I feel, is a common story - in the world we live in, pure inventors and visionaries get nowhere.

Comment: Re:What if they "fix" it in an incompatible way? (Score 2) 103

by Donwulff (#42682237) Attached to: Finland Is Crowdsourcing Its New Copyright Law

This thread of conversation seems to already have gone down the tubes, and I don't mean gas-tubes. I think most people meant it as jokes, but when future schoolchildren will Google it up they'll find this Slashdot discussion, and then update Wikipedia accordingly (Think of the children!), so to try to put the record straight on a few things...

Finland has 4 operating energy production reactors, one research/medical reactor that's in the process of being shut down (Turns out using nuclear power for good is too expensive). A fifth power-generating reactor has been under construction since 2005, and each year the expected finishing date seems to slip forward... Current projected construction cost of 8,5 billion euros cements it firmly as world's fourth most expensive construction project. That is, if it's finished on time, of course.

This all of course is slightly moot, as about 17% of Finland's total energy needs are met by the existing nuclear plants even at nearly 100% utilization. Likewise, natural gas covers only less than 10% of Finland's energy use. Predictably, like in most of the world top place is held by oil at 24%, mostly gasoline for vehicles. Second place is wood and derivatives at about 22%, then nuclear's 17%. Even coal at 11% beats out natural gas.

Although Finland is far from dependent on natural gas, the original assertion about Russia is still mostly true: Most of Finland's oil use and almost half of energy use overall are met by imports from Russia, or through Russia. The reason for this is clear from looking at the map; Finland shares land-border mostly with Russia, and the Baltic Sea is a difficult and long way to navigate for large tankers. Finland has no domestic sources of fossil energy, yet it's northern location means heating is required most of the year, making energy imports vital.

Yet discussions of Finland's energy dependency or lack of it are mostly moot for this discussion, too. Laws are passed and changed by politicians, who act like politicians do. Even in Finland, they will be willing to do anything at all that rewards them with a mention in positive light alongside whoever happens to be in charge in US at the time for example. That's pure political capital, that can be cased later on for a comfy job at some organization or other whose name begins with "World" once Russia decides to cut those energy imports.

Though to be honest, general cynicism aside, I've not seen recent statistics but I believe in Finland too most people who have or imagine they will have "valuable intellectual property", and that's most of them, believe the current laws work in their favor (Certainly artists will usually state something to the effect that they're not strict enough as is). And those with most influence will have enough money to just buy those albums, or pay people to shut up when they're caught using someone else's material.

Comment: Re:It may not be stupidity (Score 3, Interesting) 450

by Donwulff (#42269045) Attached to: North Korea's Satellite Is Out of Control

I liked that theory at first, but then I took a look at the orbital parameters... It seems to be almost pefect sun-synchronous orbit. Public experts where holding reaching sun-synchronous orbit out of reach impossibility for NK given the need to launch it at such an angle as not to have spent stages fall on ground where they could be construed a hostile action.

I'm sure we'll hear more on this in the coming hours, but it looks to me like they must've spent a lot of effort and risk on reaching sun-synchronous orbit (one conductive for earth-observation, such as spy or weather-satellites which NK claimed it would be). It doesn't seem credible that they would've done that just for a ballistic missile test and dummy payload. Also something about the way most news-sources quote the "tumbling out of control" seems to give up the impression they believe it initially had attitude control, though to be honest I'm curious to hear how they would determine when it had or didn't have attitue control.

Comment: Re:So what does the world do about it? (Score 4, Informative) 450

by Donwulff (#42268951) Attached to: North Korea's Satellite Is Out of Control

The GPS satellites have altitude well in excess of 20.000km, so for a North Korean ballistic missile launched satellite with an orbit at just around 500km to hit them would make for some big news indeed. That problem aside, you should probably know the GPS satellites are not something you go pick up at a nearby hardware store - they have a lead-time of years, decades if you count slipping them in to the budget somewhere and generally mucking around.

While at any given time there are a few irds hold on spare, should a significant number (enough for GS network to take a hit) of them be lost due to a runaway Kessler syndrome or repeat Carrington event, it would be far longer than few weeks to recover the situation. Indeed, the big worry people are hinting at is a Kessler syndrome, where our satellites decide to play a big game of billiards at orbital velocity in the sky. Not only would in theory ALL currently orbiting satellites be lost, but the debris would prevent ANY space-launches for centuries to come.

The ISS, by the way, is below 410km so quite far below the North Korean satellite for now, though the satellite's orbit is sure to decay in the future. Luckily ISS presents fairly small footprint for collissions, in the big scheme, but countless other satellites and debris lay below the satellite's current orbit. It's not good, but it's probably not catastrohic considering how frequently some satellite or other malfunctions. Our near orbit has grown so crowded however that satellites have for long been de-orbited or moved to safe orbits when taken out of service (Like that Russian satellite that was simply de-orbited rather than re-purposed because it might've received more than its alloted dose of radiation in the Van Allen belts and was therefore a risk).

A memorandum is written not to inform the reader, but to protect the writer. -- Dean Acheson