The Clarke comparison certainly grabbed my attention. My next question was "where can I find these works in English?" I see that one of the links above leads to English translations of a couple of stories.
First, I'd mod you up if I could for posting numbers.
Having said that, though, most of the efficiencybreakdowns I've seen indicate that aerodynamic loss is higher than rolling-friction loss, especially at highway speeds -- drag goes up as the square of velocity.
Looking at the page you linked, I'm a bit surprised that it says rolling resistance is two to three times higher on "tar or asphalt" than on concrete surfaces. I didn't think there was that much difference between standard, mature asphalt surface and concrete, and I imagine friction on fresh asphalt or tar would be much higher than either concrete or older asphalt. The numbers for cruising on a concrete freeway are smaller by a factor of two or three.
From the other direction, that 10% of the energy is a theoretical maximum; it assumes that your recovery process cools the tires right down to ambient temperature, that it imposes no additional drag (due to its weight or its contact with the tire), and that it sustains no losses in its own operation. None of these three assumptions seems reasonable.
It would be up to the engineers at Goodyear (not Ford) to post the actual measurements of energy that they can reclaim, and the effects that this system has on overall vehicle efficiency. I haven't seen those numbers. I suspect that we won't, or that if we do, they won't be very impressive. I'd love to be wrong, though.
A theory that ignores friction isn't especially interesting in this context.
Rolling friction is a pretty small contributor to energy loss for a moving car. Of this initially small amount of lost energy, some heats the road, and some heats the tire. As someone else observed below, the change in tire temperature is typically around 30 F, or 15-20 C, much less than a 10% change in absolute temperature. That means that a perfectly efficient heat engine could reclaim at most 10% of the thermal energy from the warm tires. In practice, the efficiency would be lower still.
Here's an infographic breaking down energy loss for an internal-combustion vehicle. Even if we assume that the electric vehicle has zero engine loss, rolling friction still represents at most maybe 20% of your energy loss. That means that you'd be reclaiming less than 2% of your total lost energy. In practice, considering the efficiency of the recapturing engine, it would probably be well under 1%; considering the added weight and mechanical loads of the recapture equipment, you might well end up losing net efficiency.
I'm not an engineer, but I have a basic understanding of thermodynamics. This story appears to be pitched at people who don't. If the engineers behind this want to convince people who know anything about physics or engineering, they're going to need something a lot better than this press release.
I have to assume that any actual engineers at Ford understand Carnot efficiency, and that this is simply an effort on the part of marketing to generate social-media buzz. It's depressing, but not surprising, to see that they're succeeding.
First of all, the target wasn't matte black, so it was already reflecting a good bit of the incoming beam. I don't know what the IR reflectivity of the hood paint and underlying steel was at the laser's wavelength, so I don't know how much.
Second of all, while a mirror layer would be more reflective, it would also be thinner and less durable than a truck's sheet-metal. So, even if it's absorbing less energy, it's also less able to dissipate it.
It is interesting to consider the conflicting demands of stealth (low reflectivity, high absorbance) and laser-resistance (high reflectivity, low absorbance).
It's fun to imagine a target covered with corner-cube reflectors (which would direct the energy back toward its source), but if the laser emitter is a mile away, I don't know how much difference they'd make.
What's your plan that doesn't somebody else (likely us taxpayers) having to support them for the rest of their lives? Are you comfortable with angry people walking around with no money, nothing to do, and completely desperate?
Perhaps that's something they should've thought about before they applied for that cushy Object Lesson opening.
How much vile and inexcusable behavior are you ready to tolerate "so taxpayers don't have to support them"?
Minecraft is one of the things I like least on the Internet right now. It epitomises everything I dislike about the environment given to the young generation, their imaginations torn from them, pushed into building artificial worlds because making in the real one is hampered by a perfect storm of regulation and fear under the umbrella of crony capitalism.
I'm sorry that your children don't get to build their own meth lab.
No, actually, that's pretty close to the non-snarky truth. I was an avid chemistry hobbyist as a kid. Already in the 1970s it was getting harder to obtain some of the materials I wanted -- all the 1950's "chemical magic" books said to go to your pharmacy for nitric acid or carbon tetrachloride or white phosphorus, but the pharmacy was having none of that. Fortunately, I had science teachers who wanted to encourage my enthusiasm, and they arranged for me to order stuff through the schools. I managed not to do too much damage to the house, the environment, or my health.
Today? Schools and pharmacies are even more locked down, but now we've got search engines and e-commerce. On balance, it's probably easier to get stuff than it used to be. But with "chemistry sets" disappearing from the shelves, fewer kids are ever getting started in the hobby.
As for having "their imaginations torn from them", though, I think you're still way off-base. My kid spends a good bit of time on Minecraft and related online pursuits, but they still haven't come for her hot-glue gun, and her tower of miniature houses, characters, and gadgets continues to grow steadily. So do the stories that she's writing, both alone and in collaboration with former classmates. It would be cool if she took after chemistry or electronics like I did, I guess, but those aren't the only fields in which to become a maker.
Well, heck. Now that we've mastered that pesky matter of grafting severed spinal cords, surely the optic nerve and other lesser bundles should be a piece of cake. So why not just do a brain transplant?
According to Wikipedia 0.075 ton/year is produced of monocrystalline silicon for use in integrated circuits.
That can't possibly be accurate. Here's a paper reporting that total consumption of fully-refined silicon for chip manufacture in 1988 was 750 metric tons. I don't think increasing process efficiencies would have reduced that figure by four orders of magnitude since then...
The cost of the raw materials is completely dwarfed by the cost of processing. Even a very large chip (2 cm x 2cm by.5mm thick) masses less than a gram. It's also likely that these high-performance III-V chips will be built on a cheaper substrate, meaning the thickness of the expensive stuff will be much, much smaller.
Competent natural-language voice recognition is still too hard for a handheld or embedded device. So, these devices digitize your voice (OMG recording!), ship it off to a server farm for interpretation, and receive the results. Because voice recognition is still a challenge, it's usually farmed out to one of a few firms (Nuance comes to mind) that do this as a third-party service. These firms can "retain" that information in the sense that it trains their voice-recognition algorithms, but they probably aren't building a huge dossier of your private conversations.
I'd certainly like to know if Samsung retains the voice information it collects. I'd even more urgently like to know if they sell it to other "third parties" besides whoever's doing the voice recognition. The initial panic I'm seeing around this looks ill-informed, but Samsung definitely has to get out in front of it. If they can't -- if they can't provide a simple, clear explanation of what they are and aren't doing -- it's going to cost them.
...or under the keister of anyone who doesn't double-check the correct spelling of a word, even though the existing spell-checker flags the correct spelling as wrong as well.
If only one of these languages would let me write a spell-checker that puts a red underline beneath words that are misspelled, and a 5KV pulse under the kiester of any "editor" who passes the wrong homophone...
Slashdot Mirror
Wonder if it's got a planet with loveable spiders? We should mount an expedition.
Companies may also make it a condition for employment, that whatever you learned on the job be wiped out, should you decide to leave...
Gosh, I'm surprised nobody ever thought of that.
The Clarke comparison certainly grabbed my attention. My next question was "where can I find these works in English?" I see that one of the links above leads to English translations of a couple of stories.
Thanks for the tip!
First, I'd mod you up if I could for posting numbers.
Having said that, though, most of the efficiency breakdowns I've seen indicate that aerodynamic loss is higher than rolling-friction loss, especially at highway speeds -- drag goes up as the square of velocity.
Looking at the page you linked, I'm a bit surprised that it says rolling resistance is two to three times higher on "tar or asphalt" than on concrete surfaces. I didn't think there was that much difference between standard, mature asphalt surface and concrete, and I imagine friction on fresh asphalt or tar would be much higher than either concrete or older asphalt. The numbers for cruising on a concrete freeway are smaller by a factor of two or three.
From the other direction, that 10% of the energy is a theoretical maximum; it assumes that your recovery process cools the tires right down to ambient temperature, that it imposes no additional drag (due to its weight or its contact with the tire), and that it sustains no losses in its own operation. None of these three assumptions seems reasonable.
It would be up to the engineers at Goodyear (not Ford) to post the actual measurements of energy that they can reclaim, and the effects that this system has on overall vehicle efficiency. I haven't seen those numbers. I suspect that we won't, or that if we do, they won't be very impressive. I'd love to be wrong, though.
To which I say, "Derp". Not sure where in the world I pulled "Ford" from, but I probably ought to wash my hands.
A theory that ignores friction isn't especially interesting in this context.
Rolling friction is a pretty small contributor to energy loss for a moving car. Of this initially small amount of lost energy, some heats the road, and some heats the tire. As someone else observed below, the change in tire temperature is typically around 30 F, or 15-20 C, much less than a 10% change in absolute temperature. That means that a perfectly efficient heat engine could reclaim at most 10% of the thermal energy from the warm tires. In practice, the efficiency would be lower still.
Here's an infographic breaking down energy loss for an internal-combustion vehicle. Even if we assume that the electric vehicle has zero engine loss, rolling friction still represents at most maybe 20% of your energy loss. That means that you'd be reclaiming less than 2% of your total lost energy. In practice, considering the efficiency of the recapturing engine, it would probably be well under 1%; considering the added weight and mechanical loads of the recapture equipment, you might well end up losing net efficiency.
I'm not an engineer, but I have a basic understanding of thermodynamics. This story appears to be pitched at people who don't. If the engineers behind this want to convince people who know anything about physics or engineering, they're going to need something a lot better than this press release.
[clicks on link]
Rats.
I have to assume that any actual engineers at Ford understand Carnot efficiency, and that this is simply an effort on the part of marketing to generate social-media buzz. It's depressing, but not surprising, to see that they're succeeding.
Probably not.
First of all, the target wasn't matte black, so it was already reflecting a good bit of the incoming beam. I don't know what the IR reflectivity of the hood paint and underlying steel was at the laser's wavelength, so I don't know how much.
Second of all, while a mirror layer would be more reflective, it would also be thinner and less durable than a truck's sheet-metal. So, even if it's absorbing less energy, it's also less able to dissipate it.
It is interesting to consider the conflicting demands of stealth (low reflectivity, high absorbance) and laser-resistance (high reflectivity, low absorbance).
It's fun to imagine a target covered with corner-cube reflectors (which would direct the energy back toward its source), but if the laser emitter is a mile away, I don't know how much difference they'd make.
If you were into the whole "reading comprehension" thing, you might have understood a list of three alternatives to the action he took.
Or you might have gone ahead and done the clueless Anonymous Coward thing anyhow, as some sort of Kaufman-esque meta-performance-art schtick.
What's your plan that doesn't somebody else (likely us taxpayers) having to support them for the rest of their lives? Are you comfortable with angry people walking around with no money, nothing to do, and completely desperate?
Perhaps that's something they should've thought about before they applied for that cushy Object Lesson opening.
How much vile and inexcusable behavior are you ready to tolerate "so taxpayers don't have to support them"?
Minecraft is one of the things I like least on the Internet right now. It epitomises everything I dislike about the environment given to the young generation, their imaginations torn from them, pushed into building artificial worlds because making in the real one is hampered by a perfect storm of regulation and fear under the umbrella of crony capitalism.
I'm sorry that your children don't get to build their own meth lab.
No, actually, that's pretty close to the non-snarky truth. I was an avid chemistry hobbyist as a kid. Already in the 1970s it was getting harder to obtain some of the materials I wanted -- all the 1950's "chemical magic" books said to go to your pharmacy for nitric acid or carbon tetrachloride or white phosphorus, but the pharmacy was having none of that. Fortunately, I had science teachers who wanted to encourage my enthusiasm, and they arranged for me to order stuff through the schools. I managed not to do too much damage to the house, the environment, or my health.
Today? Schools and pharmacies are even more locked down, but now we've got search engines and e-commerce. On balance, it's probably easier to get stuff than it used to be. But with "chemistry sets" disappearing from the shelves, fewer kids are ever getting started in the hobby.
As for having "their imaginations torn from them", though, I think you're still way off-base. My kid spends a good bit of time on Minecraft and related online pursuits, but they still haven't come for her hot-glue gun, and her tower of miniature houses, characters, and gadgets continues to grow steadily. So do the stories that she's writing, both alone and in collaboration with former classmates. It would be cool if she took after chemistry or electronics like I did, I guess, but those aren't the only fields in which to become a maker.
And whatever you do, don't let anyone learn your True Name. If they have your True Name, they have power over you.
Seems to me that "outing users", in the form of leaking their personal info without consent, is what got Lenovo in trouble in the first place.
Well, heck. Now that we've mastered that pesky matter of grafting severed spinal cords, surely the optic nerve and other lesser bundles should be a piece of cake. So why not just do a brain transplant?
Anubis? Is that you?
Sounds a bit reminiscent of the Eschaton...
According to Wikipedia 0.075 ton/year is produced of monocrystalline silicon for use in integrated circuits.
That can't possibly be accurate. Here's a paper reporting that total consumption of fully-refined silicon for chip manufacture in 1988 was 750 metric tons. I don't think increasing process efficiencies would have reduced that figure by four orders of magnitude since then...
The cost of the raw materials is completely dwarfed by the cost of processing. Even a very large chip (2 cm x 2cm by .5mm thick) masses less than a gram. It's also likely that these high-performance III-V chips will be built on a cheaper substrate, meaning the thickness of the expensive stuff will be much, much smaller.
Come on, Dice. It's the first sentence of the summary.
I was sort of expecting a post addressing today's, erm, "issue".
Competent natural-language voice recognition is still too hard for a handheld or embedded device. So, these devices digitize your voice (OMG recording!), ship it off to a server farm for interpretation, and receive the results. Because voice recognition is still a challenge, it's usually farmed out to one of a few firms (Nuance comes to mind) that do this as a third-party service. These firms can "retain" that information in the sense that it trains their voice-recognition algorithms, but they probably aren't building a huge dossier of your private conversations.
I'd certainly like to know if Samsung retains the voice information it collects. I'd even more urgently like to know if they sell it to other "third parties" besides whoever's doing the voice recognition. The initial panic I'm seeing around this looks ill-informed, but Samsung definitely has to get out in front of it. If they can't -- if they can't provide a simple, clear explanation of what they are and aren't doing -- it's going to cost them.
What, you don't like exclamation points?!!!!!! What did you expect from Medium.com?!!!!!!!!
Okay, actually, 100 microns (0.1mm) is a reasonable diameter for a human hair. So, kudos for the phrasing!
It was bad enough when the VoIP startup I worked for tried to make us use our own softswitch for phone calls in the office...
...or under the keister of anyone who doesn't double-check the correct spelling of a word, even though the existing spell-checker flags the correct spelling as wrong as well.
Guess it wasn't German-derived.
If only one of these languages would let me write a spell-checker that puts a red underline beneath words that are misspelled, and a 5KV pulse under the kiester of any "editor" who passes the wrong homophone...