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Comment Re:Now we need... (Score 1) 188

That rather depends on how the 4 billion is distributed, doesn't it? If it included all the females I suspect it'd go down rather steeply within 80 or so years.

Let's suppose it was uniform across race, sex, age, eye colour, blood group, yada yada - just as if they were drawn at random. Given that the population was at that level within my lifetime and we seemed to cope OK I'd say there'd be no effect at all.


For Future Wearable Devices, the Network Could Be You 13

angry tapir writes: Researchers at the University of California, San Diego, have found a way for wearable devices to communicate through a person's body instead of the air around it. Their work could lead to devices that last longer on smaller batteries and don't give away secrets as easily as today's systems do. From the Computerworld story: "A team led by Professor Patrick Mercier of the university's Department of Electrical and Computer Engineering has discovered a way to use the body itself as the medium for data transmission. It uses magnetic fields and shows path loss that's 10 million times lower than what happens with Bluetooth. This could make the magnetic networks much more efficient, so devices don't have to work as hard to communicate and can have smaller batteries -- or get longer useful lives with the same size batteries. The team hasn't actually tested the system's energy use yet. They envision the technology being used for networks of health sensors that monitor many parts of the body."

Comment Re:Their requirements are lacking (Score 2) 43

Most accidents occur at less than 40 mph; if "dozens of meters" equates to about 100 ft, that represents about 1.7 seconds at 40 mph. Assuming a coefficient of friction of 0.8, it is theoretically possible for a car traveling at 40 mph to stop in 67 ft; call it roughly 70 ft. If the system can apply the brakes within 500 ms, that's enough to be useful, although clearly it can't stop you from plowing into a car stopped in the fast lane of the highway.

Speaking of highways, the only reason people can manage to drive on highways is that the things you're most likely to hit are traveling in the same direction; if they were slaloming between stationary obstacles at 60 mph most drivers would be dead, fast. What makes highway driving safe is that the closing speed between vehicles is usually modest; usually on less than ten fifteen miles per hour. So actually the system might have more effect on the highway so long as speed discrepancies are in the normal range.

Comment Re: Alert! (Score 1) 216

I'll bet that for practical purposes you can't personally confirm general relativity, RNA to DNA reverse transcription, the role of the Coriolis effect in the formation of seasonal thermoclines in the ocean, or the number of stars in the Milky Way galaxy. It doesn't mean those things aren't science.

"I can't confirm it" isn't the same as "I am unable or unwilling to put the effort it would take."

Comment Re:Or for slightly less per month (Score 4, Insightful) 71

Depends on how much you use the car. Drive a brand new car off the lot to the used car dealer across the street, and you'll find the car is now worth about half what you paid for it. It takes a lot of 3.5 krona minutes to make that instantaneous depreciation seem attractive.

Now if you're like most suburban-dwelling American, you spend hours a day in your car, so it just makes sense to buy it, or lease it long-term. But if you lived and worked in Manhattan you'd be nuts to own a car for transportation unless you were a gazillionaire. Just the cost of keeping the car would exceed the cost of renting one on the rare occasions you'd need it.

I suppose most people in Copenhagen are in the same boat. It's far more walkable than most American cities and enjoys excellent bicycle and pedestrian public transit infrastructure. But every so often you and several of your friends might want to take a trip that's a little inconvenient to take by transit. If that's every day several times a day then sure, buy a car. But if it's only occasionally then it doesn't make sense to have a car sitting and depreciating in a garage somewhere.

Comment Re:Alert! (Score 4, Insightful) 216

Exactly. Science is not a democracy. We don't get to vote on the rules of physics, they are what they are even if we agree with them or not.

However we have no way of getting to know those rules except through a social process in which scientists read and argue about each others' research.

Trust me, if the majority of scientists hadn't agreed on Newton's laws of motions you'd never have heard of him. Of course then we wouldn't be having this technology-mediated conversation; we'd probably be throwing rocks at each other instead.

People that believe we should reduce carbon output and also believe that nuclear power will kill us all are rejecting science twice over.

Disproof by counterexample: me. I think we should reduce carbon output and I think nuclear power could be useful, provided that plant developers post a bond to cover the decommissioning costs. I won't bother to address your point about wind power, but I do recommend you take the the drive from Los Angeles to Palm Springs sometime. You might find it enlightening.

A true scientist would admit we know very little about the environment. Anyone that says they've solved the equation is either delusional or trying to sell something. I'm not buying.

And no true Scotsman puts sugar on his porridge.

Just because scientists don't know *everything* doesn't mean they know *nothing*, or that they don't know enough to have a more informed opinion than a layman.

Comment Re:Or for slightly less per month (Score 4, Insightful) 71

It's not intended to completely replace cars for every resident of Copenhagen (with a population far greater than 400). It's surely intended as an occasional thing for people who don't have a car, or took public transportation into the city center.

Comment Re:It's simple... (Score 1) 178

Nuclear power is so reliable, safe, and inexpensive that using wind and solar becomes nonsensical.

Reliable and safe yes, inexpensive no. Economics and a very long lead time to build are the major issues holding back the use of nukes. Numbers vary but solar and wind are now cheaper per kwh than importing brown coal to countries like India. Costs per kwh are still steadily dropping for wind and solar, whereas costs for nukes are stagnant or rising.

people will freeze to death because the sun didn't shine and the wind didn't blow when we needed it to..snip...people will die needlessly.

That's just silly fear mongering, every bit as ignorant an mis-informed as the anti-nuke people you are arguing against. Local weather variations are irrelevant to a national solar/wind grid, climate wobbles such as the el-nino phenomena mentioned in TFA have a minor impact on output because they change the average weather conditions over the entire planet. Note the impact of natural climate wobbles on output can also be positive, it just happens that the one on TFA is negative for the US (it's likely the same climate event had a positive impact on Australian renewable output).

I have no ideological problems with nukes, the appear to work very well in parts of Europe apart from the occasional political spat. However the costs and long lead times associated with building nukes means they will continue to be used in the future only where renewables are impractical. Worse still for the nuke industry, the economic niches for profitable nukes are shrinking as the renewables industry steadily continues improving their technology and ROI numbers. One thing is certain, king coal's crown is slipping, "book values" for coal assets are falling fast, the world bank, IMF, etc, have all recently stopped investing in coal and advised other to follow, nobody wants to be stuck with a "stranded asset", except the luddites running the fucking country down here in Oz, who are doing everything in their power to build the port/rail infrastructure to service "the world's largest coal mine", the mine itself is likely to fall into the "stranded asset" basket before it is even constructed.

The world is coming to an end--save your buffers!