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Comment Re:Tesla (Score 1) 272

And for the literally 99.9995 percent of the world population who doesn't have a Tesla?

As much as I'm a fan of electric cars, it's simply an absurdity to pretend that everyone's going to have one any day now. The average car on the road in the US is 10 years old, implying an average US lifespan of 20 years - and many live on even longer, shipped to the third world. So even if every new car sold tomorrow was an EV, it'd still take decades to switch over. But of course, every new car sold tomorrow won't be an EV. Even if every consumer in the world was suddenly sold on the concept of EVs, it'd take a decade or two to be able to ramp up production that high. But of course every consumer in the world isn't sold on the concept of EVs, it'll take a decade or two of people getting to experience the technology and being satisfied with it for that to happen.

I wish this wasn't the case, but the majority of the cars in the world aren't going to be electric for many decades to come. So if your plan is to stop all oil production during that time... yeah, best of luck with the end of human civilization.

Comment Re:Hoping this is not as bad as it sounds (Score 1) 272

You think the boat is just going to sit in one place? They drag the sensors behind them while they travel across tens of millions of square kilometers. At the sort of pulse rate discussed and at typical ship rates of travel for a craft like this, the pulses would be about 100 meters apart, and the ship would be dozens of miles away an hour later.

There's no point to sitting in one area and pulsing the same place over and over.

Comment Re:Not Even Funny (Score 1) 272

France also has a much milder climate and 3.5 times the population density. They're also heavily dominated by nuclear power, which some people like but others truly hate, and which tends to be one of the more expensive generation sources per kilowatt hour and with a very long turnaround time from conception to commencement of generation.

And once again, we're talking about oil here, oil and electricity are not interchangeable. You need to be comparing oil consumption per capita. France's is a bit over half the US's, but with a population density 3.5 times higher, that's kind of to be expected.

Comment Re:so long as the duration is... (Score 1) 272

For the third time I have to point it out in this thread, underwater explosions are measured differently on the decibel scale than above water explosions, you need to subtract 61.5 from the decibel figures before comparing them with above-ground noise figures. That's over 6 orders of magnitude difference.

Also, when people talk about how the ships keep making pulses every ten seconds, they act like it's in the same spot. Which would be idiotic. "Okay, now that we know what's down here, what should we explore next? I know, let's keep exploring the exact same place!" The ships pulse every 10 seconds while moving across the vast survey area.

Lastly, see my comparison with lightning above, which strikes more frequently in the survey area, louder, and often hits the same area for hours on end.

Comment Re:You're more right that you know (Score 1) 272

Nitrogen-based fertilizers generally come from natural gas, not oil, FYI. Of the three main sources of fossil energy (coal, oil, natural gas), oil is generally by far the most expensive per joule.

Also, I don't think your comparison is that simple that if yields decline, people die. If there was a global food shortage due to reduced yields per acre, the price spike would hit meat the hardest, practically driving grainfed meat off the market. A calorie of grainfed beef takes over 12 calories of grain to produce; all of that vast acreage dedicated to growing field corn for livestock feed would switch to the suddenly more valuable crops for human consumption. Meat from animals grazing on marginal lands wouldn't be more expensive to produce, although their profit margin would shoot up. The world's diet, although especially the poorer nations', would increasingly look more like it did in the past - calories primarily from plant sources with only the occasional meat supplementing it.

Also there's the fact that if price on food products skyrockets, all sorts of land that was previously considered marginal and uneconomical to produce on suddenly becomes economical.

Comment Re:Other loud noises (Score 3, Informative) 272

Common screwup. Those are all atmosphere-rated decibel figures. Underwater decibel figures are listed at 61.5 dB louder than their atmospheric equivalents. 250 dB underwater is 188.5 atmospheric.

Adjusting your above examples to be underwater figures, we get:

271.5 dB 2.0 earthquake
296.5 dB 5.0 earthquake
309.5 dB atom bomb
371.5 dB loudest volcano

I'd think it obvious that an air cannon isn't going to produce sound levels equivalent to an atomic bomb. And actually one would expect an underwater atomic bomb to be much louder than a surface one, far more of the energy is going to go into creating a gigantic oscillating bubble. And lastly, your cited atomic bomb figure is only for the 16 and 21 kiloton bombs that were dropped on Hiroshima and Nagasaki. Modern thermonuclear weapons are generally three orders of magnitude higher yield than that. A large thermonuclear weapon in deep water will create a bubble on the order of magnitude of a kilometer in size, which will then oscillate in a series of collapses and reexplosions. The oscillating bubbles created by air cannons are practically microscopic by comparison.

Comment Re:Hoping this is not as bad as it sounds (Score 4, Informative) 272

286 db at source? Air cannons are 250 db at source, so 3 and a half orders of magnitude less powerful. Lightning in the ocean is 260 db at source and your average square kilometer of ocean gets two strikes per year. These ships will be covering tens of millions of square kilometers. With a pulse rate of once every 10 seconds (3.2 million pulses per year per ship, if they run constantly, which they almost certainly won't), you're looking at an order of magnitude less per ship than lightning (and I doubt there will be many ships, and they won't always be in operation). And lightning striking water is an order of magnitude louder. It even causes shock waves in the water by the same mechanism - rapidly creating an air bubble in the water (in lightning's case, by boiling the water) which then oscillates as it implodes and explodes repeatedly.

Now, one could say that this is different because it's all in one place at a given time, and thus animals would be tempted to flee instead of it being a one-off thing. But then again, lightning strikes aren't spread out evenly over space and time either, they come in thunderstorms which do the exact same thing, repeatedly hitting the same section of sea for hours at a time.

I'm not saying that I think these ships are harmless - not at all. I just think that I think people are overplaying it when they make these apocalyptic pronouncements on what effect they'll have on sea life. I mean, people have been detonating underwater *atomic bombs* - how do you think that compares to the sound of a pop of air? At 400 feet, a blue whale's own calls (188db @ 1m) are louder than the air gun.

Comment Re:Why isn't the U.S. doing things like this? (Score 1) 156

Even the $70k price for an average-performance car here is subsidized - Toyota has admitted that they're selling it at a loss. It's hard to make an electric car look cheap, but fuel cells do a great job at it. And they have shorter lives than batteries, are more complicated with more breakable parts, operate at 1/3rd the net system efficiency well to wheel, have a larger environmental footprint for manufacture, and FCVs still have to have a hybrid-size battery pack in order to average out consumption demands so you don't have to have a 3x larger fuel cell to meet peak demand. Just ignoring the issues with the fuel itself.

Comment Re:Silly orthography (Score 1) 52

They make this sound new, but I read about this something like a decade ago. Not with CRISPR, but with "selfish genes" in general. It was proposed, as an example, to wipe out mosquitoes - or at least, one mosquito species that causes a large chunk of malaria cases but is not a major food or pollination source anywhere that it exists in the wild. They would simultaneously introduce into many parts of the population (trying to leave no breeding-isolated islands) mosquitoes bearing a selfish, recessive, lethal allele. They would spread throughout the population thanks to their gaming the laws of natural selection, without having any practial harm until it's spread throughout almost the whole population. Suddenly the population can no longer produce viable offspring, and after several generations, the species dies off.

One example of such a gene in nature was given - if I remember right, it was spotted in weevils. It causes the mothers to produce a chemical in the eggs that kills any young that don't also have the gene (aka, it codes for both a poison and its antidote). So if one parent has the gene, the only viable eggs that they get will also have the gene. It's clearly harmful - it kills off half the eggs if one of the parents has it and the other doesn't, and was detrimental in general - but like a parasite, the gene is only "concerned" with its own survival.

Comment Re:I disagree (Score 1) 241

Math is all about being precise, logical.. Communicating exactly one concept at a time. Natural languages do neither.

Except math is almost never actually done that way in practice. Euclid was wonderful, but almost all modern math does not work that strictly (and Euclid really should have been more careful with the parallel postulate -- there's "more than one thing at a time" involved there). Yes, proofs are careful and detailed, but so is, say, technical writing in English. Except for a few cases (check out metamath.org, or Homotopy Type Theory) almost no-one actually pedantically lays out all the formal steps introducing "only one concept at a time".

Comment Re: Your Results Will Vary (Score 1) 241

Not every programmer deals with these [mathematical] questions regularly (which is why I donâ(TM)t think math is necessary to be a programmer), but if you want to be a great programmer you had better bet youâ(TM)ll need it.

I don't think you need math even to be a great programmer. I do think a lot of great programmers are people who think in mathematical terms and thus benefit from mathematics. But I also believe you can be a great programmer and not be the sort of person who thinks in those terms. I expect the latter is harder, but then I'm a mathematician so I'm more than read to accept that I have some bias in this topic.

Comment Re:I disagree (Score 3, Insightful) 241

Math IS sequencing. So is using recipes. That is how math works.

Math is a language. Just because you can frame things in that language doesn't mean that that language is necessary. Recipes are often in English. English is sequencing (words are a serial stream after all). That doesn't mean English is necessary for programming (there seem to many competent non-english speaking programmers as far as I can tell).

Disclaimer: I am a professional research mathematician; I do understand math just fine.

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