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Comment: Re:Money (Score 1) 60

by lgw (#49566555) Attached to: New Privacy Threat: Automated Vehicle Occupancy Detection

HOV lanes usually increase traffic (less total people flow per minute) as they're underutilized for peak flow. They're quite politically popular for the Left however, and that's more important than infrastructure, apparently. Make them toll lanes instead, with the toll being "free" if you're not driving solo, and now the Left and Right can enjoy equally. You'll also get far more people along that highway per minute as the lane gets closer to ideal load.

Comment: Re:We have prototypes of these, working (Score 1) 98

by chihowa (#49565965) Attached to: Smart Headlights Adjust To Aid Drivers In Difficult Conditions

Are you claiming that there are no vehicular lighting standards in place, or that you can't instantly recognize the position and orientation of a car in the dark based on its lights alone?

Identifying cars based on their lights may be complicated, but it's by far the simplest method of identifying cars by CV at night.

Comment: Re:1D compression, AKA "Serialization" (Score 1) 75

by lgw (#49565787) Attached to: Holographic Principle Could Apply To Our Universe

Just about any dimensional space can be represented in fewer dimensions, or even 1 dimension

But that all misses the point here. The point of the holographic principle is not that one can imagine a 3D encoding onto a 2D surface, e.g. a holograph, but that the maximum possible information in a volume is not proportional to volume, but to surface area. That implies the fundamental mechanics of the universe can't be something like "voxels". We observe a universe which we can measure in 3 spatial dimension down to the Plank length, in principle, but that can't be what's really going on, at least if the holographic principle holds.

Comment: Re:danger vs taste (Score 2) 533

by Rei (#49565763) Attached to: Pepsi To Stop Using Aspartame

I took a look at buying Stevia in the store awhile back. I am also a reader of contents labels, so I put it back on the shelf really fast. The first ingredient listed: dextrose

Boy you're a really clever one aren't you, catching onto secret calories in stevia that nobody else did?

First off, stevia is available in many different forms. Stevia is many times more potent than sugar in terms of sweetness, it's extremely hard to use pure (I have pure stevia - to use it pure you have to make very large batches and very tiny measurements!). To dilute it down you obviously have to mix it with something. There are all sorts of mixes, but there are two main categories: those that try for parity with sugar in terms of how much you use (which generally mix with maltodextrin), and those who try for a product that is much sweeter than sugar but not as extreme as pure stevia (these can come in a variety of forms, but a common blend is with dextrose). So yes, the dextrose has calories - but it's far outmatched in terms of sweetness by the stevia therein, so you only need to use a very small amount (depending on the ratio of the blend). The 1:1 parity versions as mentioned use maltodextrin, which is also caloric - but it's so light and fluffy that there's very little mass (and thus calories) per unit volume; basically, what the stevia is blended with is mostly air.

More fun facts about stevia here [100daysofrealfood.com].

Hahaha, Food Babe? Are you joking? The woman who says she hates air travel because they compress your bodies with high pressure air and it restricts your digestive organs? And how "the air that is pumped in isn’t pure oxygen either, it’s mixed with nitrogen, sometimes almost at 50%. To pump a greater amount of oxygen in costs money in terms of fuel and the airlines know this!" Or her microwave rant, where she talks about how microwave ovens are evil because once water has been microwaved it no longer crystalizes into pure forms when frozen, but rather into forms similar to water that has heard words like "hitler" and "satan"? This is your information source?

Yeah, I think I'll stay over here in the real world and not get my information from a living joke, thanks.

Comment: Re:Not a theory! (Score 5, Interesting) 75

by lgw (#49565635) Attached to: Holographic Principle Could Apply To Our Universe

The word "theory" implies that it is testable.

"Falsifiable" is a better word here. You don't need to be able to do controlled experiments (tests) in order to have a solid theory - an influx of new observations of the universe as we find it works just as well.

And the holographic principle is certainly falsifiable.

1) It imposes a limit on the amount of entropy in any given volume - find a system which can be in more than the allowed number of states, and isn't inside a black hole, and this theory is dead.

2) It sets a really high value on the entropy of black holes. Black holes become the dominant source of entropy in our universe. This has consequences in cosmology that are fundamental, if the only reason entropy is increasing in our universe is this assigning of entropy to black holes. There are certainly physicists playing with that idea, as it could be career-making, true or false.

3) It has deep implications for the evolution of black holes - how they evaporate. This will be a lot harder to prove (I don't think we'll validate Hawking radiation in my lifetime), but might be possible to falsify by finding a black hole that's clearly not allowed by theory.

Heck, there are implications for particle physics that are still being understood, and lots there is testable now with the LHC. The more and farther you reason from a premise like this, the more likely it is to matter to something easy to measure, or at least possible to measure.

The reason the discovery of the Higgs boson was such a big deal is that it confirmed a bunch of really abstract theory in quantum mechanics that is very, very far from anything we can measure, except at the end of this very long chain of reasoning there's this prediction of this new oddball particle (that there's no other reason to expect - it come from deep in the abstract math of QM, not from anything else we measured). So finding that particle confirms that whole crazy chain of logic. Something similar will eventually happen for the holographic principle.

Comment: Re:danger vs taste (Score 1) 533

by Rei (#49565631) Attached to: Pepsi To Stop Using Aspartame

Having a strict target is not impossible, and when the difference between consumption and expenditure is on the order of 500 calories, you have room for error on both ends - on your estimation of your consumption and on the estimation of your burn.

There was a rousing ITV, or BBC, I don't remember, documentary on a woman

Whoa - throw away all of the scientific data, there's an anecdote here involving an TV show about an uncontrolled experiment whose data we can't see and whose name you can't even remember!

The human body works on calories. The human digestive system does not throw away energy from digestible substances. It's energy in vs. energy out.

Comment: Re:Easy fix (Score 3, Informative) 133

by _Sharp'r_ (#49565617) Attached to: The Engineer's Lament -- Prioritizing Car Safety Issues

Except of course, if you read the article (I know,must be new here) Ford actually _won_ the Pinto case and while they had previously (before the court case) agreed to install that plastic wall, the expert opinion was that it wouldn't actually accomplish anything and wouldn't have made any difference in the specific situation of the court case.

It's like saying horses should all be recalled because someone might fall off of them. Pintos were no more dangerous than other similar cars from all the other car companies. It's just how small, light cars were built in the days of high gas prices and associated regulations. Technology has advanced since then, but there are still trade-offs.

What most people "know" about Pintos is largely media-driven, not factual.

Comment: Re:With the best will in the world... (Score 1) 398

by Rei (#49564703) Attached to: Audi Creates "Fuel of the Future" Using Just Carbon Dioxide and Water

Of that, its 1.4 litre turbo-charged diesel engine weighs about 90kg.

The engine, of course, being only part of the drivetrain components that can be eliminated by a switch to electric drive. Transmission, radiator, all fluids, fuel, the whole exhaust system, etc. In some designs you can even replace the driveshaft. You basically gut 90% of the moving parts.

The fuel tank holds about 42 litres of diesel weighing... whatever that weighs.

About 30 kilos.

It can do 600 miles urban or ~700 miles motorway, driving normally.

And that spec is relevant why? No seriously, please tell me. In what sort of realistic scenario is it critical to be able to drive for 700 miles nonstop without ever setting foot out of your car? How can you even do that? Do you not pee? Do you not eat? Even if you could it's not safe to drive that long nonstop, a person is supposed to take regular rest breaks. You stop for lunch, you plug your car into a fast charger, and you go off on your way afterwards.

The reason gas and diesel cars have such huge tanks has nothing at all to do with that being some sort of remotely practical requirement. It's to minimize a great inconvenience of ICE vehicles, that is, how often you have to go out of your way in your daily life at regular intervals in whatever weather it is and stand outside pumping fuel into your car. In your daily life, you never have to do this with EVs. Not once.

The longest range electric car that I can actually touch right now is the Tesla Model S; It's 3 times the size of my car, weighs over twice as much and has a third of the mileage, and costs 10x as much.

Really, we're going to compare a brand new luxury sports sedan with a used family car? That's the comparison we're going for? Have you tried comparing your car with a Bugatti Veyron?

Comment: Re:With the best will in the world... (Score 1) 398

by Rei (#49564607) Attached to: Audi Creates "Fuel of the Future" Using Just Carbon Dioxide and Water

Slow down there. You're comparing the complete-cycle efficiency for petroleum to just the end-stage efficiency for electric.

You seem to have not noticed what this article is about. It's about making fuel from electricity and then giving it to cars. Both sides start with the same feedstock: electricity. So it doesn't matter how efficient the electricity was to make because it affects both paths equally.

But let's switch back to your "scenario that I want to talk about that's not the one in the article"

Slow down there. You're comparing the complete-cycle efficiency for petroleum to just the end-stage efficiency for electric. That electricity needs to be made somehow. Toss in 40% efficiency for coal plants (we'll leave out pumping/mining and fuel transport costs for now, assuming they're similar for oil and coal), battery charging efficiency of about 75% [futurepundit.com] (discharge efficiency is unspecified, but since the EPA mileage estimates are based on battery capacity it's safe to ignore it), and the 85% motor efficiency you've specified, and suddenly your EV is .4*.75*.85 = 25.5% efficient. Same as a diesel.

I don't see that figure in your link, and I don't really need your link because I'm familiar with the numbers already. It depends on what you mean by "charging efficiency". The US grid averages about 8% distribution losses, plant to breaker. Li-ions are over 99% efficient at slow charging, but depending on the type can drop a few percent in faster charging scenarios, and in an extreme situation down to the lower 90%s. The charger itself has some losses, if I recall correctly from the breaker they're usually 92-94% efficient. So a good middle of the road number is more like 84%.

Also note that EVs automatically also function as hybrids: they regen and don't "idle".

Their EV is cheaper to operate not because the EV is more energy-efficient, but because coal is so much cheaper than gasoline

Coal is of course the dirtiest widely used power source, and its usage is declining in most first-world countries. Natural gas and wind have the highest growth rates. The most efficient combined cycle natural gas plants are upwards of 60% efficient, although that's not an "average" efficiency, but even old plants are generally over 40%. Efficiencies on things like wind, solar, etc are of course not particularly meaningful, since you're not burning a fuel. Nuclear has a low efficiency, but again, that's not particularly meaningful.

Even putting solar panels on your roof and amortizing the costs in most climates makes running an EV cheaper than gasoline. It's not because coal is somehow ridiculously cheap. It's because oil is a really expensive energy source per joule.

Wind is only about twice the costs of coal

If this was true, people would be churning out new coal plants, not wind farms.

Comment: Re:danger vs taste (Score 1) 533

by Rei (#49564477) Attached to: Pepsi To Stop Using Aspartame

No, it doesn't break down in the stomach. It breaks down in the small intestine. Very, very rapidly, leaving no detectable levels in the blood,.

The most recent study I read was in 2008 or so (and yes, I read the entire thing)

You read one study among the hundreds on one of the most highly studied food additives in history? Great, let me know when you're done with the others. ;) And I'm sure there was zero selection bias in your choice of which of the many studies to read ;)

Wikipedia covers the "cancer" thing well enough for a primer:

Reviews have found no association between aspartame and cancer. These reviews have looked at numerous carcinogenicity studies in animals, epidemiologic studies in humans, as well as in vitro genotoxicity studies. These studies have found no significant evidence that aspartame causes cancer in animals, damages the genome, or causes cancer in humans at doses currently used.[8][38][41] This position is supported by multiple regulatory agencies like the FDA[58] and EFSA as well as scientific bodies such as the National Cancer Institute.[47]

Concern about possible carcinogenic properties of aspartame was originally raised and popularized in the mainstream media by John Olney in the 1970s and again in 1996 by suggesting that aspartame may be related to brain tumors. Reviews have found that these concerns were flawed, due to reliance on the ecological fallacy[59] and the purported mechanism of causing tumors being unlikely to actually cause cancer. Independent agencies such as the FDA and National Cancer Institute have reanalyzed multiple studies based on these worries and found no association between aspartame and brain cancer.[41]

As discussed in the article on controversies around aspartame, the Cesare Maltoni Cancer Research Center of the European Ramazzini Foundation of Oncology and Environmental Sciences released several studies which claimed that aspartame can increase several malignancies in rodents, concluding that aspartame is a potential carcinogen at normal dietary doses.[60][61] The EFSA[62] and the FDA[58] discounted the study results due to lack of transparency and numerous flaws in the study, finding no reason to revise their previously established acceptable daily intake levels for aspartame.

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