We don't need to build "brains" anymore than we need to build "walkers" (i.e. machines that walk), wheels work much better.
Do they? Wheels are efficient in their milieu, but they are limited. Wheels are great if you have a smooth roadway or a rail for them to ride on. When you get into slippery, boggy or uneven surfaces, you sometimes can't use wheels at all. There is a reason that the Dante robot (sent to probe a volcano) was a six-legged walker instead of a wheeled or tracked machine; legs can handle things that the others cannot.
Roads and rails can be viewed as an example of fitting the problem to our solution, adapting the way we live to our technology instead of vice versa. (Wouldn't *you* rather have grass, flowers and trees than streets and highways?) One of the reasons we might want to build artificial brains is because our computers don't have the flexibility to deal with the world in the ways we'd like them to. How much hassle have we gone through to "pave over" problems to make them suitable for our computer systems to handle? Food for thought.
It is by caffeine alone I set my thoughts in motion.
It is by the beans of Java that my thoughts acquire speed, the hands acquire shaking, the shaking becomes a warning. It is by caffeine alone I set my thoughts in motion.
The debris in itself would be moving towards the sun, due to it's gravitation
Much like our Earth is.
Actually, really small debris particles get blown right out of the Solar System by light pressure. Slightly larger dust particles "see" the same light pressure coming from just a bit ahead of the Sun (due to their orbital velocity), which gives them a continuous braking force; they spiral into the Sun if they don't hit a planet first. And all of this stuff can be seen, because it scatters light.
The most interesting prospect that occurs to me is that it could be an example of dark matter in the form of Weakly Interacting Massive Particles (WIMPs). Particles which do not interact via the electromagnetic force would not scatter light nor be affected by inter-atomic forces, and those which do not interact via the strong force would go right through nuclei as well; such particles would be phantoms, only feeling the weak nuclear force and gravity. The planets orbitting in the inner system would tend to eject such particles which ventured in too close, but those in a halo outside the outer planets would be undisturbed. As the probes passed out of the planetary zone and into the halo, they would begin to feel the pull of its mass (there is zero pull inside of a spherical shell). This would manifest itself as an increase in gravity, just as is being observed.
It's been known for many years that galaxies have a lot of mass that isn't visible. Maybe the Pioneers have revealed some of it in our own back yard. Now wouldn't that be cool!
FYI: 3 hydrogen atoms/m^3 is the critical density of the universe as a whole, IIRC; galaxies are lots denser.
BUt it could be something new, like the heliopause ending closer to the sun than thought...
Unlikely. The Solar wind is moving faster than waves can travel through it (supersonic). When a supersonic flow encounters an obstacle (and the heliopause is going to be one), it creates shock waves, turbulence and all kinds of fun. In a magnetized plasma like the solar wind this means lots of energized electrons spiralling around lines of magnetic force, creating synchrotron radiation and whatnot. The heliopause will be detectable from some distance away by its radio emissions; it won't sneak up as a curious change in the spacecraft drag.
There is no suggestion in Katz's article about Clotho being tailored to your wishes.
I don't think you read the same article I did. Katz hints at a lot of stuff that's completely at odds with your interpretation. Some quotes, emphasis in boldface added:
Clotho would ask. If not, she'd vaporize the thing, or failing that rate it 1.5. She'd keep it away from us.
There's an implication of user-determined thresholds.
Perhaps she could draw from Slashdot's amazing and elaborate discussion moderating systems (where offensive speech isn't banned but smothered in cool software programs), and meta-moderate technology for us.
And there's a hint toward peer moderation - something that would take heed of appraisals of other people. Katz isn't a technologist, and if you're flaming him because he doesn't explicitly spell out the possibility of having lots of different appraisers and using or ignoring them as you see fit - don't you have anything better to do?
We might program her to screen out anything under a 4.
That's more than a hint.
People love to hate Katz, and that's fine; taste is taste. But putting your own words into his mouth so you can flame him doesn't benefit the Slashdot community - or anything besides your ego. If you want to flame your strawman, go right ahead. I'm sure it will burn beautifully, though not for long.
...
what Katz is suggesting is more or less the director of programmation on a television station. He determines what people consider useful or entertaining.
Got a quote to back up that statement? Because I don't see anything in Katz's article to suggest that he expected Clotho to rate everything the same for everyone (a la TV where everyone sees the same program if they select the channel).
I cut off the freedom of expression of the WWW all the time. I don't take time to browse more than a very few sites every day, and most of those come to my attention through pointers on/. or from friends. If Clotho-agent software helps me rank stuff before I spend eyeball time on it, and updates its data about what I find interesting or useful as it goes, it'll be useful and will get used. If it's unhelpful, it'll fall by the wayside. That's the way these things work.
Why should an AI (buzzword, btw) censor what I see and not see? Why should an AI (buzzword) play God (buzzword) when I can't?
It's too late. Millions of people are doing this already, and you probably are too. Or don't you realize that every time you use a search engine, you are employing an AI to select (call it "censor" if you like) what you see (based on your own search criteria), and it certainly "plays God" (weeds through vastly more material than you could yourself).
(mmontour beat me to some of this... posting anyway...)
We continue to use, to this day, AC running at 60 Hz, due to Edison's twisted marketing. While all electricity is dangerous in foolish hands, 60 Hz is one of the most dangerous base frequencies for electricity due to it being near the operating frequency for nerve cells. It takes nearly 100 times the electricity at 14 Hz to kill a man than it does at the peak dangerousity of 60Hz.
Actually, we use 60 Hz because it's more efficient than 14 Hz. The size of the transformer is inversely proportional to the frequency it carries; that's why the toroid in your PC's 300 watt power supply is so small compared to the same size isolation transformer. Europe runs on 50 Hz.
The real limitations are due to physics and engineering. Europe uses 220 volts for house current, which saves money on wiring. We don't use frequencies much higher than 60 Hz for most things because the eddy-current losses in the transformer laminations get too high, and the reactance of long-distance power lines gets out of hand.
It's sick that Edison is taught to the children to be some kind of genius hero, when in actually he was a scheming, theiving, murderer. And Telsa is nearly forgotten.
Oh, you mean that the name of the unit of magnetic flux intensity has been forgotten? (1 Tesla = 1 Weber/m^2.) Every double-E learns about Tesla's work in detail. And even if most do not know Tesla's name, their lives are influenced far more by Tesla's fractional-horsepower induction motor than by Edison's DC empire. Look at the legacy.
Primarily for his invention that would have allowed for nearly free electrical generation by installing very very tall towers around the planet which would use the Earth's magnetic field to generate pollutionless electricity!
Sorry, that's not correct. Tesla's work was primarily involved with transmitting power (rumor has it he melted down one plant's generators trying to power one of his wireless experiments). As proof of the bankruptcy of the "suppressed-free-energy" conspiracy, look at the facts: despite almost a century of improvements in science, you still can't point to the physics that would make such a device work. Nature's laws are there for everyone; you can't stop people from discovering them.
There are whole nations with lots of scientists, plenty of know-how, and nothing to lose by taking a free-energy machine (or a 200 MPG carburetor) to the world. Imagine how competitive Japan would be if they didn't have to import fossil fuels. If it could be done, they'd be doing it. The truth of the matter is that even genuises sometimes wind up barking up the wrong tree. Einstein goofed, Tesla goofed. Just proves they were only human.
Compared to the number of people murdered by self-styled Christians claiming they want to "save the babies" or trying to start holy race wars, 7 doesn't sound so impressive. It's had plenty of coverage, unlike your average anti-abortion arson.
Besides which, it's unclear that the loonie went into the church for any reason other than that it was there. He may have hated the whole world and the church building was the first thing he came to. If he'd driven his car over two dozen kids waiting for a school bus to take them home it couldn't be reliably interpreted to mean that he had something against education, youth or vehicles with red blinking lights either. The loon may not have known what he meant himself; the disconnect may be what finally drove him over the edge.
Stop taking every chance explosion of a loon that happens to come your way, or your individual sampling of volume of news coverage, as evidence of a conspiracy against you. It's probably just the editors' tastes, or judgement of what will sell advertising, not matching yours.
How far away can you see a ship? Not THAT far.
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That would only get you a few more miles.
If you had studied your trigonometry, you'd know that the angle you can see around a sphere is related to the observer's height by a simple formula: the height of the observer (from the center of the sphere) is given by the radius times the secant of the angle. The distance across the surface of the sphere between the observer's nadir and the horizon is, of course, directly proportional to the angle.
What does this mean? Assume you're standing on a 100 meter cliff or tower looking over a waveless sea. The Earth's radius is about 6.4e6 meters, so the angle you can see is arccos( 6.4e6 / 6.4001e6 ) = 0.32 degrees. If there was a ship with a 50-meter mast, you'd just be able to see the tip of it over the sea if it was another 0.22 degrees beyond your horizon. Taken together, you could see 0.54 degrees, or about 32 nautical miles. A ship sailing at 5 knots would cover that in 6 hours and a fraction. Days in advance? Ridiculous.
Publicity on the stuff that makes LE more able to track, classify and snoop is long overdue.
Of course, the real screaming will come when the government-watchers demand access to all the cameras and sensors and put them to work watching the government. Can you imagine having a real-time display of the locations of all the legislators... and lobbyists... in Washington? See who's in bed with whom, and who's chatting just a little too much with the wealthy contributor who just happens to to be trying to compromise so-and-so's position on an issue that's near and dear to you?
Unless sunshine comes first and hardest to the government itself, government is just being hypocritical. It should not be allowed to do anything to the public that it does not first do to itself.
If the list and ranking of questions is to be frozen at a particular time, perhaps the thread should be archived at the same time. This would avoid any confusion about what should or should not have been sent to the interviewee, as well as avoiding wasted work/points on the part of the moderators (assuming that work and points spent changing the rankings of posts is wasted if it does not affect the short list).
With the SSN and a few names (perhaps available from a genealogical database like the Mormon church's) it is possible to get credit in someone's name, drain their bank accounts, and other nasty tricks. It can take a lot of time and trouble to sort out the mess. And every school employee is wearing a badge with their SSN on it...
I'm sure I'm not the only person thinking that if the school principal had personal issues to deal with, he wouldn't be putting much time and effort into defending this indefensible invasion of privacy.
Why is it that 50% of the people in my building have adding-machines on their desk - next to their computer?
It's because the keypad on the adding machine is big enough to be keyed quickly, and it probably has a tape-printer for verifying that all the numbers are correct. It's fast and convenient for what it does, and the users can go a lot faster with it than they can with the computer.
It's the same difference with a calculator vs. Matlab, or the omnipresent editor wars. I'm currently waiting for delivery of new editor software because I refuse to waste my time learning the obscure key-chording of MultiEdit; I can get something with vi emulation, and it's much more efficient to spend a bit on software than to take the huge performance hit involved with re-training all of my reactions. Experienced users can get their stuff done with vi, HP calculators, and adding machines without having to think about how to get there. The savings in time more than pays for the additional hardware, software and desk space.
This is somewhat off-topic, but neutrinos have long been a staple of science fiction plots. Examples:
Larry Niven's "deep radar".
The scanning technology used to detect the first "bobbles" in The Peace War (Vernor Vinge).
I also recall a relatively recent short story in Analog which got the hazards of being close to (as in, on a planet around) a supernova right: unless you have a neutrino shield, the number of neutrino-collision events in your body will kill you almost instantly from radiation effects. Dumping a solar mass of high-energy neutrinos overwhelms the tiny odds of any one of them deigning to notice that your atoms exist.
If only it worked that way. The figure I've seen is that a neutrino can go through a trillion miles of lead without interacting with anything, so your chances of detecting an individual neutrino are vanishingly small. Unless you can generate enormous quantities (with enormous energy requirements), you won't get enough of a signal at your detector to be able to communicate. Fortunately for Comsat, their technology is unlikely to be supplanted by neutrino systems any time soon.
A previous idea to do just this, the DUMAND (Deep Underwater Muon And Neutrino Detector) was originally proposed to be put in some very clear water which lies off the coast of Hawaii (IIRC). The detectors would have consisted of long strings of glass buoys anchored to the ocean floor, with very sensitive photodetectors to catch the faint flashes of Cerenkov radiation from newly-created muons racing through the water.
I don't know what became of DUMAND; it may have fallen prey to Congress in a budget cycle, because it was too small to have a constituency to defend it. Kind of like NASA's science programs. <sigh>
This happened in Guam. Brown tree snakes were introduced and their reign of terror began.
I believe you are correct. I also read about a scheme for killing the snakes: "mousicles" (frozen mouse pups with poison pills inside them) are dropped in the forest inside cardboard tubes. Snakes can get into the tubes to eat them, most other things can't. Result: the snakes die. I hope it works, it's clever.
Still, I always wonder what to do when an endangered animal only eats endangered plants.
The situation with the dodo appears to be the opposite. The dodo evolved in sync with a number of other species, including trees. IIRC, there is a species of tree whose fruit is too large for anything else to eat comfortably, and it requires passage through a bird's digestive system before it will germinate. After the passage of the dodo, this tree had few or no seedlings until someone decided to force-feed the fruits to turkeys; the seeds passed by the turkeys germinated and grew. Bringing back the dodo would restore the populations of these trees as well (then again, so would breeding giant turkeys which would eat these fruits).
Not to start a flamewar, but there are distinctions that tgd misses persistently. In the interest of accuracy, I'm going to deconstruct his last post also.
One thing you may want to add to your list of things you hate: accusing someone of igorance with a criticism that demonstrates far more ignorance than the comment you are critisizing.
Careful, son. You just added English to your list of demonstrated marginal skills. At the rate you're going, you'll be in remedial classes by next week. Just a hint: I've been at this (writing to get my point across, physics, and the Net, as well as aviation) long enough to know what I'm doing. You obviously have not.
Aircraft attitude-control systems use aerodynamic forces, not gyroscopic, to aim the nose in the desired direction. The gyros are for reference, not reaction.
No kidding? Really? Damn, no wonder I had to push on those pedel things and turn that wheel last time I was flying a plane. I was confused for a moment. Betcha I was talking about the artificial horizon. Ooops. Probably should've spelled that out. My bad.
Betcha you didn't know that the auto-pilot, which uses an attitude gyro, does not torque the airplane around by the little wheel spinning behind the panel; it's just a reference in space used to define "up" and "heading". All the twisting of the airplane is done with servos moving the control surfaces, just like the ball-bot will need its twisting done by pushing against the cabin air with its fans.
Incidentally, I hope you don't forget to pull power next time you do a spin to the left. If the engine is cranked up to speed the gyro effect of the prop can hold the nose up and put you into a flat spin, and judging from your comments above I don't know if you'd be able to reliably recover from the normal situation.
Here's an experiment for you kids at home: Take the wheel off your bike. Hold on to both sides of the axle, and get someone to spin it for you. Try to rotate it. Every first grader has done that in science class (except in Kansas where the wheel doesn't exist because the Bible has the value of Pi wrong, and Man never evolved to calculate it better...). You most certainly can stabilize an object from rotational forced using three gyrosopes aligned to each axis.
Notice something else when doing that experiment: If you try to use the gyro wheel to torque yourself around or resist an outside torque, it precesses; the axis of rotation shifts direction. This destroys your 3-space reference. Gyro tables are gimballed and often servoed to offset bearing friction in the gimbals; the whole point is to avoid torquing the gyros, so they will remain pointing in the same direction in space.
Oh, and they're frequently used in missile guidance systems for stabilization, not just referance.
... providing direction and rate information to the servo systems which control the flight surfaces and/or thrust vector. As I said, they provide a reference, not torque.
'Fraid he's right and you're not. You have exactly three perpendicular axes, so three thrust lines will do. To balance torque around each one, you have two fans per axis. Each fan pair can pull as well as push, so you do not need two fans per face. Three axes * 2 fans/axis = 6 fans.
'Fraid you're doing the same thing he did, assuming you've got to be able to control movement in three axis when maneuvering in 3-D. Obviously you've never tried it. I haven't in zero-g, obviously, but I have underwater. You need to be able to move along X, Y, and Z, plus rotate around those axis (yaw, pitch, roll). Otherwise you can't turn around. And notice in the diagrams there's a camera. Sucks if something interesting is happening behind it and it can't turn around.
To turn around: Activate both yaw fans or both pitch fans in the same direction (I'm implicitly assuming that the fan pairs are coaxial, pushing along the same line through the ball's CG). Reaction from fan momentum and torque dissipated in the air causes the ball to rotate. When rotation is complete, de-spin by reversing the rotation of both fans. Voila, the camera is pointing somewhere else.
Just a hint: you're not symmetrically buoyant in the water. Your legs are a lot heavier than your lungs, giving you a head-up bias. You can't generalize from what you experience paddling around with your hands to zero-G.
You don't need two fans per face, that's true. But unless you have them equidistant from the center of gravity, you have stability and control issues. If you have them inline, spinning in opposite directions (one fan blade has its blades inverted), then you can cancel it out. But with only six, you need to vent the air for the opposite site through the device, with as little resistance as you get on the powered side.
Not necessary. Air will flow over the surface of the sphere and detach on the opposite side where the converging flows cause the pressure to increase and make the boundary layer separate. Nothing needs to go through the sphere unless it's convenient, which leaves you room for nice things like cameras, computers, batteries and motors.
Tough to get right, but doable. Not much room for electronics in a sphere like that after you do, however. Six just can't do it. Hell, four can't do it in 2-D, because you still have X, Y, and orientation (three axis instead of six).
If you'd care to place a small wager on the results of the NASA development effort and the number of fans it requires, feel free to contact me. I love betting on a sure thing.
Look up Froude efficiency, and compare that of an air jet to a fan 4 cm across. Then compute the energy capacity of a volume of compressed air at 1000 PSI, and the same volume of NiMH battery. How long can each deliver 0.01 Newton of thrust? Show your work.
You're operating in a nearly frictionless environment. Efficiency isn't an issue. You need accuracy in thrust. Releasing compressed gas through an accurate valve is a lot more precise than issues with varying efficiency of a fan at different speeds, and compensating for spin-up time. But that's neither here nor there. Six gas jets, six fans, either way its simply not going to work.
I see you failed to do the physics. Also:
You're not in a frictionless environment; cabin fans produce air currents, which will continuously drag anything in their path with them. Holding position against air currents is part of the job, and it requires more or less continuous thrust.
Efficiency is an issue for speed of motion (how many accelerate/stop cycles to.5 m/sec can you do before you run out of juice?) as well as operating time between recharges.
You've not explained why an air jet is more precisely controllable than a fan coupled to an electric motor. The air jet is either on or off; the motor is potentially controllable from zero to max RPM in infinitesimal steps.
I could go on, but I'm bored now.
Maybe you oughta stop reading the fortune cookies, and think more about your posts.
Always nice to see a man who takes his own advice.;-)
If there's anything I hate, it's ignorance of something so basic as elementary physics.
Okay, not to throw a light of doubt on this, but I'm not so sure an A/C claiming to work at NASA throwing around some ideas should really be trusted.
The AC comment appears well-informed, unlike your criticism. Taking yours apart point by point:
1) The fans spinning wouldn't be an issue with a simple fixed-axis gyroscopic system like they use in airplanes for the horizon control.
Aircraft attitude-control systems use aerodynamic forces, not gyroscopic, to aim the nose in the desired direction. The gyros are for reference, not reaction.
2) You can't use one of those with six fans, that's the biggest proof that this guy doesn't know what he's talking about.
'Fraid he's right and you're not. You have exactly three perpendicular axes, so three thrust lines will do. To balance torque around each one, you have two fans per axis. Each fan pair can pull as well as push, so you do not need two fans per face. Three axes * 2 fans/axis = 6 fans.
I also can't imagine that carrying compressed air really would be an issue.
Look up Froude efficiency, and compare that of an air jet to a fan 4 cm across. Then compute the energy capacity of a volume of compressed air at 1000 PSI, and the same volume of NiMH battery. How long can each deliver 0.01 Newton of thrust? Show your work.
Confucius say: Is better to be silent and be thought a fool, than to speak and remove all doubt. I believe the AC; I can't take you seriously.
Flying one on the Vomit Comet would be a fairly easy way to shake it down, and cheap compared to a rocket launch. A business jet is certainly a lot cheaper to operate than even the Vomit Comet, can probably fly the required parabolic arc, and is likely roomy enough to test a robot intended for use in confined spaces. You just have to make sure that the robot lands on something that won't break the fan blades between periods of free fall.
It would be pretty much trivial to have straightening vanes on all the fans, so that the net torque is zero... or not. Another solution is contra-rotating fans on opposite faces; they can either produce thrust while cancelling torque, or produce torque while cancelling thrust. This allows the fans to push, twist, or any combination along/around the axis of the fan shafts. Pairs arranged as top/bottom and left/right look easy, but a back/forward pair appears problematic for little things like the camera field of view.
It was not the education courses, she was willing and did take those. She did not have the right kind of MATH courses. The state required college algebra and college geometry.
Now that's absurd. In my high school, the less-advanced students took "Senior Math Analysis" (I took it my sophomore year, having had algebra and geometry in junior high). This was an algebra/trigonometry course; the more advanced students graduated with calculus under their belts.
A state which requires prospective teachers to take geometry and algebra at the college level implicitly expects teacher candidates to be stuck in remedial classes. Given the poor showings of ed-school applicants on all the standardized tests it isn't at all surprising that many of them might need to, but to go from there and say that they have to is shocking. If anything, those applicants who require remediation should not be allowed to enter teachers-ed programs. (BTW, what state is this, and how long ago?)
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Roads and rails can be viewed as an example of fitting the problem to our solution, adapting the way we live to our technology instead of vice versa. (Wouldn't *you* rather have grass, flowers and trees than streets and highways?) One of the reasons we might want to build artificial brains is because our computers don't have the flexibility to deal with the world in the ways we'd like them to. How much hassle have we gone through to "pave over" problems to make them suitable for our computer systems to handle? Food for thought.
The most interesting prospect that occurs to me is that it could be an example of dark matter in the form of Weakly Interacting Massive Particles (WIMPs). Particles which do not interact via the electromagnetic force would not scatter light nor be affected by inter-atomic forces, and those which do not interact via the strong force would go right through nuclei as well; such particles would be phantoms, only feeling the weak nuclear force and gravity. The planets orbitting in the inner system would tend to eject such particles which ventured in too close, but those in a halo outside the outer planets would be undisturbed. As the probes passed out of the planetary zone and into the halo, they would begin to feel the pull of its mass (there is zero pull inside of a spherical shell). This would manifest itself as an increase in gravity, just as is being observed.
It's been known for many years that galaxies have a lot of mass that isn't visible. Maybe the Pioneers have revealed some of it in our own back yard. Now wouldn't that be cool!
People love to hate Katz, and that's fine; taste is taste. But putting your own words into his mouth so you can flame him doesn't benefit the Slashdot community - or anything besides your ego. If you want to flame your strawman, go right ahead. I'm sure it will burn beautifully, though not for long.
I cut off the freedom of expression of the WWW all the time. I don't take time to browse more than a very few sites every day, and most of those come to my attention through pointers on /. or from friends. If Clotho-agent software helps me rank stuff before I spend eyeball time on it, and updates its data about what I find interesting or useful as it goes, it'll be useful and will get used. If it's unhelpful, it'll fall by the wayside. That's the way these things work.
The future is here, get used to it.
dkm: Thanks. I've been looking for a replacement for cyperpunk.
The real limitations are due to physics and engineering. Europe uses 220 volts for house current, which saves money on wiring. We don't use frequencies much higher than 60 Hz for most things because the eddy-current losses in the transformer laminations get too high, and the reactance of long-distance power lines gets out of hand.
Oh, you mean that the name of the unit of magnetic flux intensity has been forgotten? (1 Tesla = 1 Weber/m^2.) Every double-E learns about Tesla's work in detail. And even if most do not know Tesla's name, their lives are influenced far more by Tesla's fractional-horsepower induction motor than by Edison's DC empire. Look at the legacy. Sorry, that's not correct. Tesla's work was primarily involved with transmitting power (rumor has it he melted down one plant's generators trying to power one of his wireless experiments). As proof of the bankruptcy of the "suppressed-free-energy" conspiracy, look at the facts: despite almost a century of improvements in science, you still can't point to the physics that would make such a device work. Nature's laws are there for everyone; you can't stop people from discovering them.There are whole nations with lots of scientists, plenty of know-how, and nothing to lose by taking a free-energy machine (or a 200 MPG carburetor) to the world. Imagine how competitive Japan would be if they didn't have to import fossil fuels. If it could be done, they'd be doing it. The truth of the matter is that even genuises sometimes wind up barking up the wrong tree. Einstein goofed, Tesla goofed. Just proves they were only human.
Besides which, it's unclear that the loonie went into the church for any reason other than that it was there. He may have hated the whole world and the church building was the first thing he came to. If he'd driven his car over two dozen kids waiting for a school bus to take them home it couldn't be reliably interpreted to mean that he had something against education, youth or vehicles with red blinking lights either. The loon may not have known what he meant himself; the disconnect may be what finally drove him over the edge.
Stop taking every chance explosion of a loon that happens to come your way, or your individual sampling of volume of news coverage, as evidence of a conspiracy against you. It's probably just the editors' tastes, or judgement of what will sell advertising, not matching yours.
If you had studied your trigonometry, you'd know that the angle you can see around a sphere is related to the observer's height by a simple formula: the height of the observer (from the center of the sphere) is given by the radius times the secant of the angle. The distance across the surface of the sphere between the observer's nadir and the horizon is, of course, directly proportional to the angle.
What does this mean? Assume you're standing on a 100 meter cliff or tower looking over a waveless sea. The Earth's radius is about 6.4e6 meters, so the angle you can see is arccos( 6.4e6 / 6.4001e6 ) = 0.32 degrees. If there was a ship with a 50-meter mast, you'd just be able to see the tip of it over the sea if it was another 0.22 degrees beyond your horizon. Taken together, you could see 0.54 degrees, or about 32 nautical miles. A ship sailing at 5 knots would cover that in 6 hours and a fraction. Days in advance? Ridiculous.
Of course, the real screaming will come when the government-watchers demand access to all the cameras and sensors and put them to work watching the government. Can you imagine having a real-time display of the locations of all the legislators ... and lobbyists ... in Washington? See who's in bed with whom, and who's chatting just a little too much with the wealthy contributor who just happens to to be trying to compromise so-and-so's position on an issue that's near and dear to you?
Unless sunshine comes first and hardest to the government itself, government is just being hypocritical. It should not be allowed to do anything to the public that it does not first do to itself.
If the list and ranking of questions is to be frozen at a particular time, perhaps the thread should be archived at the same time. This would avoid any confusion about what should or should not have been sent to the interviewee, as well as avoiding wasted work/points on the part of the moderators (assuming that work and points spent changing the rankings of posts is wasted if it does not affect the short list).
I'm sure I'm not the only person thinking that if the school principal had personal issues to deal with, he wouldn't be putting much time and effort into defending this indefensible invasion of privacy.
It's the same difference with a calculator vs. Matlab, or the omnipresent editor wars. I'm currently waiting for delivery of new editor software because I refuse to waste my time learning the obscure key-chording of MultiEdit; I can get something with vi emulation, and it's much more efficient to spend a bit on software than to take the huge performance hit involved with re-training all of my reactions. Experienced users can get their stuff done with vi, HP calculators, and adding machines without having to think about how to get there. The savings in time more than pays for the additional hardware, software and desk space.
- Larry Niven's "deep radar".
- The scanning technology used to detect the first "bobbles" in The Peace War (Vernor Vinge).
I also recall a relatively recent short story in Analog which got the hazards of being close to (as in, on a planet around) a supernova right: unless you have a neutrino shield, the number of neutrino-collision events in your body will kill you almost instantly from radiation effects. Dumping a solar mass of high-energy neutrinos overwhelms the tiny odds of any one of them deigning to notice that your atoms exist.If only it worked that way. The figure I've seen is that a neutrino can go through a trillion miles of lead without interacting with anything, so your chances of detecting an individual neutrino are vanishingly small. Unless you can generate enormous quantities (with enormous energy requirements), you won't get enough of a signal at your detector to be able to communicate. Fortunately for Comsat, their technology is unlikely to be supplanted by neutrino systems any time soon.
I don't know what became of DUMAND; it may have fallen prey to Congress in a budget cycle, because it was too small to have a constituency to defend it. Kind of like NASA's science programs. <sigh>
Incidentally, I hope you don't forget to pull power next time you do a spin to the left. If the engine is cranked up to speed the gyro effect of the prop can hold the nose up and put you into a flat spin, and judging from your comments above I don't know if you'd be able to reliably recover from the normal situation.
Notice something else when doing that experiment: If you try to use the gyro wheel to torque yourself around or resist an outside torque, it precesses; the axis of rotation shifts direction. This destroys your 3-space reference. Gyro tables are gimballed and often servoed to offset bearing friction in the gimbals; the whole point is to avoid torquing the gyros, so they will remain pointing in the same direction in space.Just a hint: you're not symmetrically buoyant in the water. Your legs are a lot heavier than your lungs, giving you a head-up bias. You can't generalize from what you experience paddling around with your hands to zero-G.
Not necessary. Air will flow over the surface of the sphere and detach on the opposite side where the converging flows cause the pressure to increase and make the boundary layer separate. Nothing needs to go through the sphere unless it's convenient, which leaves you room for nice things like cameras, computers, batteries and motors. If you'd care to place a small wager on the results of the NASA development effort and the number of fans it requires, feel free to contact me. I love betting on a sure thing. I see you failed to do the physics. Also:- You're not in a frictionless environment; cabin fans produce air currents, which will continuously drag anything in their path with them. Holding position against air currents is part of the job, and it requires more or less continuous thrust.
- Efficiency is an issue for speed of motion (how many accelerate/stop cycles to
.5 m/sec can you do before you run out of juice?) as well as operating time between recharges. - You've not explained why an air jet is more precisely controllable than a fan coupled to an electric motor. The air jet is either on or off; the motor is potentially controllable from zero to max RPM in infinitesimal steps.
I could go on, but I'm bored now. Always nice to see a man who takes his own advice.Confucius say: Is better to be silent and be thought a fool, than to speak and remove all doubt. I believe the AC; I can't take you seriously.
Flying one on the Vomit Comet would be a fairly easy way to shake it down, and cheap compared to a rocket launch. A business jet is certainly a lot cheaper to operate than even the Vomit Comet, can probably fly the required parabolic arc, and is likely roomy enough to test a robot intended for use in confined spaces. You just have to make sure that the robot lands on something that won't break the fan blades between periods of free fall.
It would be pretty much trivial to have straightening vanes on all the fans, so that the net torque is zero... or not. Another solution is contra-rotating fans on opposite faces; they can either produce thrust while cancelling torque, or produce torque while cancelling thrust. This allows the fans to push, twist, or any combination along/around the axis of the fan shafts. Pairs arranged as top/bottom and left/right look easy, but a back/forward pair appears problematic for little things like the camera field of view.
A state which requires prospective teachers to take geometry and algebra at the college level implicitly expects teacher candidates to be stuck in remedial classes. Given the poor showings of ed-school applicants on all the standardized tests it isn't at all surprising that many of them might need to, but to go from there and say that they have to is shocking. If anything, those applicants who require remediation should not be allowed to enter teachers-ed programs. (BTW, what state is this, and how long ago?)