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Comment Re:Their requirements are lacking (Score 1) 17

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) 88

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 2) 32

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 3, Insightful) 88

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:Won't someone think of hurting the children?? (Score 0) 127

In many parts of the world, it's actually illegal for a 14-year-old to have a paid position.

It is now illegal in the United States as well, but when I grew up a lot of kids worked. I made good money and was able to afford to go on ski trips and purchase musical equipment, and later pay for car insurance and gas. Yes, most other parents just paid for stuff like that for their kids, but we didn't have much money. My mom was a single mom, and I actually worked at the same restaurant where she worked, so I made about the same per hour as she did. I just was only working about 25 to 30 hours a week, and she was working more like 50 to 60.

Comment Re:Won't someone think of hurting the children?? (Score 1) 127

I don't know what country you lived in. Perhaps Australia?

The U.S.A, a country that once existed on the North American continent.

As for what your parents would have insisted on... well, if they never did, all I have is your expectation. If they did I would call them abusive. Paying your debts is one thing, getting something on your record and being subject to the abuse of the "criminal justice" system is something totally else.

They never did, because I was raised right and didn't get into trouble. It is not abusive to allow someone to bear the consequences of their actions. It is abusive NOT to.

Comment Re:It's simple... (Score 1) 154

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.

Comment Re:Sexting can harm children (Score 1) 127

It's nice that the police said:

"'Sexting' may seem like a harmless or normal activity but there are many risks involved. Once circulated, the sender loses all control of that image and can cause significant distress when it gets into wider hands. It is essential that we work, alone and alongside partners such as schools and families, to intervene early and prevent young people from becoming both the victims and perpetrators of crime."

How nice of the police to recognize that sexting has risks, and then they demonstrate that the police response is the biggest risk by filing a police report that will follow him for the next 10 years.

This is really dumb. This is like being arrested for "accessory to burglary" if you fail to lock your door.

Comment Re:3D programming requirements (Score 1) 584

No. I am one of the primary authors of what might be fairly described as a Photoshop-class application -- one with far more layer modes and built-in filters than Photoshop, as well as a full-bore built-in ray tracer and texturing facility. It is also considerably smaller and faster than Photoshop in the identical system environment. I am also the author of multiple realtime video and arcade games, etc. I'm telling you flat out that matrices are not required. Period.

Matrices may be the only way you know how to do these kinds of graphics; but they definitely aren't the only way to do it.

Just to take your example: "if you have 3-vectors (i.e. points relative to the origin in 3-space), any global linear transformation is represented by a matrix multiplying each vectors"

The correct way to state this is: "if you have 3-vectors (i.e. points relative to the origin in 3-space), any global linear transformation can be represented by a matrix multiplying each vectors." Here is the non-matrix approach (and of course, there's always polar, which can also be easily handled.) This is for 2D points; 2D vectors and 3D points and vectors are all just a further (and trivial) generalizations of the following:

Translation: X += deltaX; Y += DeltaY
Rotation: X = X * cos(theta) - Y * sin(theta); Y = Y * cos(theta) + Y * sin(theta);
Scaling: X *= Xfactor; Y *= Yfactor

Shadows and reflections can be trivially accomplished with more of the same. Basically: R = 2(V dot N)N - V

"dot" is just the dot product, which again is a trivial combination of the lowest math primitives. ...and so on.

You are confusing the fact that matrices can be used to do something with the idea that matrices are the something.

With algebra, trig, and basic math in hand, the programmer's doors to 2D and 3D graphics are wide open.

"Can you program?" "Well, I'm literate, if that's what you mean!"

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