As well as Sedgewick and Kernighan, Robert Tarjan (major graphs algorithm researcher) is also in your rather star-laden department, and according to a friend of mine is currently working on digital watermarking methods.
Given that you've been so prominent in demonstrating the weakness of watermarking techniques thus far, how do you like his company's chances of succeeding, and has your academic interest in defeating watermarking schemes resulted in some interesting debates in the lunchroom?
Good for you. Do you mind if I borrow them? Seriously, I was just trying to make the point that I was trying the test with decent (if not studio-quality audiophile) equipment rather than total rubbish.
Oh, and did I mention that cans do nothing for imaging and soundstage?
That's why I tried it through the stereo (burnt.wav files to CD, played through decent but admittedly not particularly high-end component). My stereo system isn't perfect, but it's better than 95% of the prefab crap most people own. Either way, I still couldn't tell the difference.
Don't pay attention to the numbers, listen to the music!
I have. Records sound like shit, particularly after repeated playing. The snap, crackle, and pop is dead easy to hear, and *entirely* absent from CD's.
I tried those "blind listening tests" that were featured on/. a while ago (can't be bothered digging up URL) and I couldn't tell the difference using $150 Sennheiser headphones through an SBLive Value, nor my $1000 stereo setup (though my CD player isn't the greatest). I still maintain that badly encoded MP3s sound like crap, but from that test it seems to me that modern encoders are better than my ears, even at 128 kbps, and these days I count as a semi-professional musician (I get beer to play in a cafe:) ).
Even if we had unlimited quantities of helium-3 sitting in tanks on Earth, we don't have the ability to do generate power with controlled fusion with it anyway. I think current guesses are that cost-effective fusion power plants, on Earth, using the deuterium-tritium reaction which is easier to do than D-He3, are at least a couple of decades away, so D-He3 space drives are probably at least 30-40 years away. It'd be nice to go to Mars before then.
Contrary to assumptions (and an episode of "The Goodies"), from all reports the dodo wasn't particularly tasty. "Hard, rubbery flesh" or something like it was the verdict apparently.
It hasn't flown (was Re:Visions of the Future)
on
Inventions of 2001
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· Score: 2
More to the point, the prototype hasn't flown yet. When we see movie footage of the thing taking off, doing a quick once-around-the-block, and landing under its own steam, *then* get excited:)
Yes, but that's the primary requirement for getting a Mars mission up - convincing enough people that it's a good idea so it'll get funding (most likely from government, possibly privately).
but it's surely expensive
It cost about a million US dollars, IIRC. That's chicken feed compared to what it costs to develop propulsion systems and stuff.
One would think that developing cheaper ways to send rockets to Mars and the like would have a lot more long term benefit considering the Mars Society's goals.
Their next planned major experiment is basically to put a bunch of mice in low earth orbit in a craft rotating so as to provide simulated Mars-level gravity. If successful, the mice will reproduce and eventually be brought back to earth for study.
Such a mission will provide much information on the feasibility of both using artificial gravity on a manned Mars mission (thus avoiding problems of loss of muscle tone, bone demineralisation etc.), and whether raising mammal babies in Martian gravity will be feasible (crucial to the feasibility of one day colonising Mars).
Lots of explorers, some of whom weren't particularly sane, managed to survive extended periods of similar isolation and once they went out they didn't have *any* contact with others outside their own party for months or even years. Or, to take another example, what about the crews of WWII U-Boats? From all reports, most of them stayed sane, under conditions that seem to me to be similar (but harsher) than those faced by a hypothetical Mars mission.
Or consider the contestants on Big Brother - the producers choose them specifically because they believe that they'll be entertaining on television when mixed in with the other contestants, not for mental stability. They don't allow them any contact with their family and friends while they're in the house. They don't provide them with any news of the outside world. They *do* spy on them 24 hours a day. They ply them with alcohol in attempts to get them to do things they wouldn't otherwise do. And yet the overwhelming majority of contestants on the various versions around the world came out sane and (publically at least) claim to have enjoyed the experience.
Now, I'm not claiming that being a member of a Mars crew wouldn't be challenging, stressful, and lonely at times. I find it hard to believe that it's beyond the efforts of a specially-selected, well-trained team.
Would it be a stretch to imagine those alien beings having the ability to directly sense microwaves, similar to our ability to see and hear?
No, that's entirely reasonable, but at any realistic range the signal is so weak that you'd need a bloody great big dish to concentrate that signal enough to "hear" it. I find it somewhat implausible that there are creatures that have evolved into radio telescopes:)
If they can construct a radio dish (even if they just use it like a reflecting telescope to shine the radio waves into their microwave "eyes" they'd presumably have to know at least a little geometry.
Because it gets rid of the ability by the world's largest cartel to dicate the price of the product they sell.
Medium-size oil, without the massive R&D budgets of big oil but lacking the nimbleness of startups, would likely be in big trouble if we shifted to hydrogen fuel cells.
Sure, it's a standard pro-forma "foo is the enemy" sales memo, but it is notable that "foo" is Linux (though it's difficult to see what other enemy Microsoft's sales force faces for low-end stuff).
As I read it, fuel cell technology (for cars) is still kinda immature even for experimental race vehicles.
Besides which, everything in these solar vehicles, including the aerodynamics, efficient electric motors, the power management, and so on, is directly applicable to future fuel cell vehicles anyway.
I have to say that, in most aspects, she'd find most of Europe, Canada, Australia, and New Zealand pretty similar in those respects. In some aspects some of those places offer less freedom (restrictions on guns, clamps on some aspects of political expression), but some offer more (better privacy laws, freedom to take narcotics if one so chooses without the threat of oppressive law enforcement, freedom to gamble at a casino if one so chooses).
Yes, the U.S. should be proud of its achievements in offering freedoms to its citizens both through its legal system and the wealth generated by its economy. However, it's not perfect, and other countries share many of those good qualities.
That article was singularly uninformative, but it strikes me as possible that in the future instead of electricity transmission wires, electricity generation plants will simply electrolyse water, and we'll turn the hydrogen back to energy in domestic fuel cells.
The benefits are considerable:
no transmission losses (except for leakage and pumping costs)
the ability to deliver it in trucks to remote areas, or even ship it between continents, just like oil.
No need for peak load generators, because you can just store a surplus of hydrogen during low-demand times and release it during peak periods.
Very efficient at fuel-cell end - most of the waste heat runs the household hot-water system.
Solution: move a small mining plant (manned, essentially a shack and some dozers) to the moon, build a railgun, launch the raw materials to Geosync, process the materials, and build the powersat from construction shacks manned by a few dozen men.
Hmmm. How many off-earth factories do we have right now? How much R&D will be needed to design the first off-earth factory? How many launches from Earth will it require to keep those few dozen workers fed, clothed, and supplied with all the parts, tools, and other things they need to do the job (notably carbon to process the silicon, something present only in miniscule quantities on the moon). For fsck's sake, obtaining water on the moon isn't exactly easy (there might be some at the poles, but if so it'll be located in craters that never see the sun). Oh, and where are you going to get the power to extract bulk quantities of aluminium?
Now, none of these problems are insurmountable, given enough effort However, all that effort strikes me as a *very* expensive and long-termexercise. By the time it becomes feasible, one wonders whether fusion power will have been perfected and all this effort to be irrelevant.
Basically we've reduced this to those who fly half way around the world. And how many people do that often enough to make up for development costs? It aint ever going to happen.
You'd have to be an American (what is it - 80% of Americans don't have a passport?) to make a dumb statement like that. The Boeing 747 is a device developed exclusively for just that purpose, and it seems to have made a reasonable amount of cash for its developers.
According to him, those things were *immensely* manual.
During that era, they certainly were. I had a look at an Australian Oberon diesel submarine from the era (it's moored at the maritime museum in Sydney), and to make it do *anything* was incredibly complex. Firing a torpedo required adjusting half a dozen different valves, manually loading the torpedo from storage, and so on.
As well as the controls on the bridge, though, they were duplicated in various other parts of the ship, so if the bridge controls were damaged you could launch a torpedo from the crew quarters, IIRC. They basically slept next to them.
Of course, these days you could replace most of that with a controller and some relays. It'd be interesting to have a look at a Collins-class sub to see how much of the fire sequence is now automated.
WRT Patton and Doolittle vs Montgomery, isn't there an contrary body of opinion which says Montgomery was a stodgy plodder who wasted golden opportunities while he sat around and piled up equipment, whereas Patton seized opportunities as they were presented?
I want the computer watch that Inspector Gadget's niece (the animated series, not the crappy movie) had. Not only could it control every mechanical device on earth, it must of sad some kinda whacky chording system to let her to do all that stuff with three buttons:)
O'Neill colonies would use exactly the same solar cells as we could use here on earth. Now, say due to the lack of clouds and the 24-hour exposure, they generate, say, 4 times the power that a similar area would here. Maybe your transmission losses would be 25%, so you're back to 3 times the performance.
Then you've got the costs of either a) moving the solar cells from Earth (or maybe the moon) to the right spot, or b) moving a whole heap of, say, asteroid to the right spot, then manufacturing them there (and presumably the solar-cell plant has to come from Earth). Either is going to be a heck of a lot more expensive than manufacturing them on earth and shipping them to central Australia, say.
Sorry, I can't see how this is going to fly. Maybe the solar-powered laser thing (beaming the laser at earth using the energy to make hydrogen from water) the Japanese are currently experimenting with might be a possibility, but with conventional solar cells I just can't see it.
Sure the average CS student might not be particularly bright outside their area of expertise, but in my experience at university (in Australia) the average biol student was even worse. The strong students in both areas had interests beyond their subject areas, though, and I'd back the CS student's understanding of biology well ahead the average biol student's understanding of CS.
As far as decent writing skills, CS students weren't great. Biol students were appalling. I know, I read their lab reports - it was a struggle.
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Given that you've been so prominent in demonstrating the weakness of watermarking techniques thus far, how do you like his company's chances of succeeding, and has your academic interest in defeating watermarking schemes resulted in some interesting debates in the lunchroom?
Good for you. Do you mind if I borrow them? Seriously, I was just trying to make the point that I was trying the test with decent (if not studio-quality audiophile) equipment rather than total rubbish.
That's why I tried it through the stereo (burnt .wav files to CD, played through decent but admittedly not particularly high-end component). My stereo system isn't perfect, but it's better than 95% of the prefab crap most people own. Either way, I still couldn't tell the difference.
I have. Records sound like shit, particularly after repeated playing. The snap, crackle, and pop is dead easy to hear, and *entirely* absent from CD's.
I tried those "blind listening tests" that were featured on /. a while ago (can't be bothered digging up URL) and I couldn't tell the difference using $150 Sennheiser headphones through an SBLive Value, nor my $1000 stereo setup (though my CD player isn't the greatest). I still maintain that badly encoded MP3s sound like crap, but from that test it seems to me that modern encoders are better than my ears, even at 128 kbps, and these days I count as a semi-professional musician (I get beer to play in a cafe :) ).
"Songs of Distant Earth" was actually by Arthur C. Clarke. Nice little book, IMHO.
Even if we had unlimited quantities of helium-3 sitting in tanks on Earth, we don't have the ability to do generate power with controlled fusion with it anyway. I think current guesses are that cost-effective fusion power plants, on Earth, using the deuterium-tritium reaction which is easier to do than D-He3, are at least a couple of decades away, so D-He3 space drives are probably at least 30-40 years away. It'd be nice to go to Mars before then.
Contrary to assumptions (and an episode of "The Goodies"), from all reports the dodo wasn't particularly tasty. "Hard, rubbery flesh" or something like it was the verdict apparently.
More to the point, the prototype hasn't flown yet. When we see movie footage of the thing taking off, doing a quick once-around-the-block, and landing under its own steam, *then* get excited :)
Yes, but that's the primary requirement for getting a Mars mission up - convincing enough people that it's a good idea so it'll get funding (most likely from government, possibly privately).
It cost about a million US dollars, IIRC. That's chicken feed compared to what it costs to develop propulsion systems and stuff.
Their next planned major experiment is basically to put a bunch of mice in low earth orbit in a craft rotating so as to provide simulated Mars-level gravity. If successful, the mice will reproduce and eventually be brought back to earth for study.
Such a mission will provide much information on the feasibility of both using artificial gravity on a manned Mars mission (thus avoiding problems of loss of muscle tone, bone demineralisation etc.), and whether raising mammal babies in Martian gravity will be feasible (crucial to the feasibility of one day colonising Mars).
Or consider the contestants on Big Brother - the producers choose them specifically because they believe that they'll be entertaining on television when mixed in with the other contestants, not for mental stability. They don't allow them any contact with their family and friends while they're in the house. They don't provide them with any news of the outside world. They *do* spy on them 24 hours a day. They ply them with alcohol in attempts to get them to do things they wouldn't otherwise do. And yet the overwhelming majority of contestants on the various versions around the world came out sane and (publically at least) claim to have enjoyed the experience.
Now, I'm not claiming that being a member of a Mars crew wouldn't be challenging, stressful, and lonely at times. I find it hard to believe that it's beyond the efforts of a specially-selected, well-trained team.
I don't know orbital mechanics, but the quoted figures I've seen for this have made that assumption.
Why not? Don't we do aerobraking every time we deorbit the Space Shuttle?
No, that's entirely reasonable, but at any realistic range the signal is so weak that you'd need a bloody great big dish to concentrate that signal enough to "hear" it. I find it somewhat implausible that there are creatures that have evolved into radio telescopes :)
If they can construct a radio dish (even if they just use it like a reflecting telescope to shine the radio waves into their microwave "eyes" they'd presumably have to know at least a little geometry.
Medium-size oil, without the massive R&D budgets of big oil but lacking the nimbleness of startups, would likely be in big trouble if we shifted to hydrogen fuel cells.
Sure, it's a standard pro-forma "foo is the enemy" sales memo, but it is notable that "foo" is Linux (though it's difficult to see what other enemy Microsoft's sales force faces for low-end stuff).
Besides which, everything in these solar vehicles, including the aerodynamics, efficient electric motors, the power management, and so on, is directly applicable to future fuel cell vehicles anyway.
Yes, the U.S. should be proud of its achievements in offering freedoms to its citizens both through its legal system and the wealth generated by its economy. However, it's not perfect, and other countries share many of those good qualities.
The benefits are considerable:
Is such a system ever going to be feasible?
Hmmm. How many off-earth factories do we have right now? How much R&D will be needed to design the first off-earth factory? How many launches from Earth will it require to keep those few dozen workers fed, clothed, and supplied with all the parts, tools, and other things they need to do the job (notably carbon to process the silicon, something present only in miniscule quantities on the moon). For fsck's sake, obtaining water on the moon isn't exactly easy (there might be some at the poles, but if so it'll be located in craters that never see the sun). Oh, and where are you going to get the power to extract bulk quantities of aluminium?
Now, none of these problems are insurmountable, given enough effort However, all that effort strikes me as a *very* expensive and long-termexercise. By the time it becomes feasible, one wonders whether fusion power will have been perfected and all this effort to be irrelevant.
You'd have to be an American (what is it - 80% of Americans don't have a passport?) to make a dumb statement like that. The Boeing 747 is a device developed exclusively for just that purpose, and it seems to have made a reasonable amount of cash for its developers.
During that era, they certainly were. I had a look at an Australian Oberon diesel submarine from the era (it's moored at the maritime museum in Sydney), and to make it do *anything* was incredibly complex. Firing a torpedo required adjusting half a dozen different valves, manually loading the torpedo from storage, and so on.
As well as the controls on the bridge, though, they were duplicated in various other parts of the ship, so if the bridge controls were damaged you could launch a torpedo from the crew quarters, IIRC. They basically slept next to them.
Of course, these days you could replace most of that with a controller and some relays. It'd be interesting to have a look at a Collins-class sub to see how much of the fire sequence is now automated.
WRT Patton and Doolittle vs Montgomery, isn't there an contrary body of opinion which says Montgomery was a stodgy plodder who wasted golden opportunities while he sat around and piled up equipment, whereas Patton seized opportunities as they were presented?
BUY OUR MERCHANDISE
It's been pretty effective, too :)
I want the computer watch that Inspector Gadget's niece (the animated series, not the crappy movie) had. Not only could it control every mechanical device on earth, it must of sad some kinda whacky chording system to let her to do all that stuff with three buttons :)
Then you've got the costs of either a) moving the solar cells from Earth (or maybe the moon) to the right spot, or b) moving a whole heap of, say, asteroid to the right spot, then manufacturing them there (and presumably the solar-cell plant has to come from Earth). Either is going to be a heck of a lot more expensive than manufacturing them on earth and shipping them to central Australia, say.
Sorry, I can't see how this is going to fly. Maybe the solar-powered laser thing (beaming the laser at earth using the energy to make hydrogen from water) the Japanese are currently experimenting with might be a possibility, but with conventional solar cells I just can't see it.
As far as decent writing skills, CS students weren't great. Biol students were appalling. I know, I read their lab reports - it was a struggle.